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Molecules, Volume 17, Issue 6 (June 2012) – 97 articles , Pages 6179-7611

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1508 KiB  
Article
Synthesis of Chalcones with Anticancer Activities
by Suvitha Syam, Siddig Ibrahim Abdelwahab, Mohammed Ali Al-Mamary and Syam Mohan
Molecules 2012, 17(6), 6179-6195; https://doi.org/10.3390/molecules17066179 - 25 May 2012
Cited by 204 | Viewed by 15209
Abstract
Several chalcones were synthesized and their in vitro cytotoxicity against various human cell lines, including human breast adenocarcinoma cell line MCF-7, human lung adenocarcinoma cell line A549, human prostate cancer cell line PC3, human adenocarcinoma cell line HT-29 (colorectal cancer) and human normal [...] Read more.
Several chalcones were synthesized and their in vitro cytotoxicity against various human cell lines, including human breast adenocarcinoma cell line MCF-7, human lung adenocarcinoma cell line A549, human prostate cancer cell line PC3, human adenocarcinoma cell line HT-29 (colorectal cancer) and human normal liver cell line WRL-68 was evaluated. Most of the compounds being active cytotoxic agents, four of them with minimal IC50 values were chosen and studied in detail with MCF-7 cells. The compounds 1, 5, 23, and 25 were capable in eliciting apoptosis in MCF-7 cells as shown by multiparameter cytotoxicity assay and caspase-3/7, -8, and -9 activities (p < 0.05). The ROS level showed 1.3-fold increase (p < 0.05) at the low concentrations used and thus it was concluded that the compounds increased the ROS level eventually leading to apoptosis in MCF-7 cells through intrinsic as well as extrinsic pathways. Full article
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269 KiB  
Article
Antiatherogenic Properties of Acetone Extract of Alpinia zerumbet Seeds
by Jamnian Chompoo, Atul Upadhyay, Shinichi Gima, Masakazu Fukuta and Shinkichi Tawata
Molecules 2012, 17(6), 6237-6248; https://doi.org/10.3390/molecules17066237 - 25 May 2012
Cited by 147 | Viewed by 7950
Abstract
Oxidation of low-density lipoprotein (LDL) is the principal risk factor for the development of atherosclerosis. In this study, we used several methods to investigate the ability of the acetone extract from rhizomes, stems, leaves, flowers, pericarps and seeds of Alpinia zerumbet to inhibit [...] Read more.
Oxidation of low-density lipoprotein (LDL) is the principal risk factor for the development of atherosclerosis. In this study, we used several methods to investigate the ability of the acetone extract from rhizomes, stems, leaves, flowers, pericarps and seeds of Alpinia zerumbet to inhibit atherosclerosis in vitro. The seed extract had the strongest activity against tyrosinase, pancreatic lipase (PL), 15-lipoxygenase (15-LO) and LDL oxidation activities (IC50 = 2.30 ± 0.02, 5.00 ± 0.07, 1.29 ± 0.07 and 15.40 ± 0.86 µg/mL, respectively), amongst all different parts. It also had similar effects to the positive controls. Most of the extracts showed partial agonistic properties towards estrogenic activity. Cholest-4-ene-3,6-dione, a steroid present only in the seed extract seems to be the compound responsible for these activities. The results showed that cholest-4-ene-3,6-dione had similar ability to curcumin and quercetin against PL and LDL oxidation (IC50 = 19.50 ± 1.17 and 16.12 ± 1.43 µg/mL, respectively). Furthermore, cholest-4-ene-3,6-dione (IC50 = 34.21 ± 1.31 µg/mL) had higher inhibition against 15-LO than quercetin (IC50 = 54.79 ± 1.12 µg/mL). Full article
(This article belongs to the Section Medicinal Chemistry)
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915 KiB  
Article
Synthesis and Antiangiogenic Activity of Novel Gambogic Acid Derivatives
by Tao Chen, Rong-Hong Zhang, Shi-Chao He, Qin-Yuan Xu, Liang Ma, Guang-Cheng Wang, Neng Qiu, Fei Peng, Jin-Ying Chen, Jing-Xiang Qiu, Ai-Hua Peng and Li-Juan Chen
Molecules 2012, 17(6), 6249-6268; https://doi.org/10.3390/molecules17066249 - 25 May 2012
Cited by 23 | Viewed by 5271
Abstract
Gambogic acid (GA) is in a phase II clinical trial as an antitumor and antiangiogenesis agent. In this study, 36 GA derivatives were synthesized and screened in a zebrafish model to evaluate their antiangiogenic activity and toxicity. Derivatives 4, 32, 35 [...] Read more.
Gambogic acid (GA) is in a phase II clinical trial as an antitumor and antiangiogenesis agent. In this study, 36 GA derivatives were synthesized and screened in a zebrafish model to evaluate their antiangiogenic activity and toxicity. Derivatives 4, 32, 35, 36 effectively suppressed the formation of newly grown blood vessels and showed lower toxicities than GA as evaluated by zebrafish heart rates and mortalities. They also exhibited more potent migration and HUVEC tube formation inhibiting activities than GA. Among them, 36 was the most potent one, suggesting that it may serve as a potential new antiangiogenesis candidate with low toxicity. Additionally, 36 showed comparable antiproliferative activity to HUVECs and five tumor cell lines but low cytotoxicity to LO2 cells. Full article
(This article belongs to the Section Medicinal Chemistry)
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249 KiB  
Article
α-Glucosidase Inhibitory Constituents from Acanthopanax senticosus Harm Leaves
by Zhi-Bin Wang, Hai Jiang, Yong-Gang Xia, Bing-You Yang and Hai-Xue Kuang
Molecules 2012, 17(6), 6269-6276; https://doi.org/10.3390/molecules17066269 - 25 May 2012
Cited by 26 | Viewed by 5873
Abstract
A new triterpene glycoside, 3-O-[(α-L-rhamnopyranosyl)(1→2)]-[β-D-glucuronopyranosyl-6-O-methyl ester]-olean-12-ene-28-olic acid (1) and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5) were isolated from the leaves of Acanthopanax senticosus Harms along with six known [...] Read more.
A new triterpene glycoside, 3-O-[(α-L-rhamnopyranosyl)(1→2)]-[β-D-glucuronopyranosyl-6-O-methyl ester]-olean-12-ene-28-olic acid (1) and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5) were isolated from the leaves of Acanthopanax senticosus Harms along with six known compounds. The structures of the new compounds were determined by means of 2D-NMR experiments and chemical methods. All the isolated compounds were evaluated for their glycosidase inhibition activities and compound 6 showed significant α-glucosidase inhibition activity. Full article
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1118 KiB  
Article
Scutellaria baicalensis Alleviates Cantharidin-Induced Rat Hemorrhagic Cystitis through Inhibition of Cyclooxygenase-2 Overexpression
by Steven Kuan-Hua Huan, Kun-Teng Wang, Shauh-Der Yeh, Chia-Jung Lee, Li-Chun Lin, Der-Zen Liu and Ching-Chiung Wang
Molecules 2012, 17(6), 6277-6289; https://doi.org/10.3390/molecules17066277 - 25 May 2012
Cited by 29 | Viewed by 5420
Abstract
Cantharidin, an active component in mylabris, is used in traditional Chinese medicine (TCM) to treat scabies and hepatoma, but accompanied by hemorrhagic cystitis. Evidence shows that cantharidin induces human bladder carcinoma cell death through COX-2 overexpression in vitro. In TCM, Scutellaria baicalensis [...] Read more.
Cantharidin, an active component in mylabris, is used in traditional Chinese medicine (TCM) to treat scabies and hepatoma, but accompanied by hemorrhagic cystitis. Evidence shows that cantharidin induces human bladder carcinoma cell death through COX-2 overexpression in vitro. In TCM, Scutellaria baicalensis is usually used to cure mylabris-induced hematuria. This work was undertaken to determine the mechanisms of cantharidin-induced rat hemorrhagic cystitis and explore the uroprotective effect of S. baicalensis. In vitro results showed cantharidin could induce cytotoxicity through prostaglandin (PG)E2 overproduction of T24 cells. Boiling-water extract of S. baicalensis (SB-WE) could significantly inhibit PGE2 production and COX-2 expression in lipo-polysaccharide-induced RAW 264.7 cells, indicating obvious anti-inflammatory abilities. In vivo results indicated that cantharidin caused rat hemorrhagic cystitis with hematuria via c-Fos and COX-2 overexpression. SB-WE was given orally to cantharidin-treated rats, whereby hematuria level, elevated PGE2 and COX-2 protein overexpression were significantly and dose-dependently inhibited by SB-WE. The anti-inflammatory components of SB-WE are baicalin and wogonin, whose contents were 200.95 ± 2.00 and 31.93 ± 0.26 μg/mg, respectively. In conclusion, cantharidin induces rat cystitis through c-Fos and COX-2 over-expression and S. baicalensis can prevent the resulting hematuria because of its anti-inflammatory effects. Full article
(This article belongs to the Section Natural Products Chemistry)
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586 KiB  
Article
Biological Activities of a-Pinene and β-Pinene Enantiomers
by Ana Cristina Rivas da Silva, Paula Monteiro Lopes, Mariana Maria Barros de Azevedo, Danielle Cristina Machado Costa, Celuta Sales Alviano and Daniela Sales Alviano
Molecules 2012, 17(6), 6305-6316; https://doi.org/10.3390/molecules17066305 - 25 May 2012
Cited by 440 | Viewed by 26311
Abstract
The antimicrobial activities of the isomers and enantiomers of pinene were evaluated against bacterial and fungal cells. The agar diffusion test showed that only the positive enantiomers of the a- and β-isomers of pinene were active. The minimal inhibitory concentration (MIC) and minimal [...] Read more.
The antimicrobial activities of the isomers and enantiomers of pinene were evaluated against bacterial and fungal cells. The agar diffusion test showed that only the positive enantiomers of the a- and β-isomers of pinene were active. The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) of these monoterpenes were also determined, confirming that the positive enantiomers exhibited microbicidal activity against all fungi and bacteria tested with MICs ranging from 117 to 4,150 µg/mL. However, no antimicrobial activity was detected with the negative enantiomers up to 20 mg/mL. Time-kill curves showed that (+)-a-pinene and (+)-β-pinene were highly toxic to Candida albicans, killing 100% of inoculum within 60 min. By contrast, the bactericidal effect occurred after 6 h in methicillin-resistant Staphylococcus aureus (MRSA). In combination with commercial antimicrobials, ciprofloxacin plus (+)-a-pinene or (+)-β-pinene presented synergistic activity against MRSA whereas an indifferent effect against all fungi was detected when amphotericin B was combined with the positive enantiomers of pinene. The potential of (+)-a-pinene and (+)-β-pinene to inhibit phospholipase and esterase activities was also evaluated, and the best inhibition results were obtained with Cryptococcus neoformans. C. albicans biofilm formation was prevented with the MIC concentration of (+)-a-pinene and twice the MIC value of (+)-β-pinene. Finally, the cytotoxicity of the positive enantiomers of pinene to murine macrophages was evaluated, and 250 µg/mL of (+)-a-pinene and (+)-β-pinene reduced the cell viability to 66.8% and 57.7%, respectively. Full article
(This article belongs to the Collection Bioactive Compounds)
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289 KiB  
Article
Synthesis and Biological Evaluation of Novel N-Methyl-picolinamide-4-thiol Derivatives as Potential Antitumor Agents
by Ting-Ting Huang, Yun-Chuang Huang, Xiao-Yu Qing, Yong Xia, Xun Luo, Ting-Hong Ye and Luo-Ting Yu
Molecules 2012, 17(6), 6317-6330; https://doi.org/10.3390/molecules17066317 - 25 May 2012
Cited by 498 | Viewed by 6141
Abstract
A novel series of N-methylpicolinamide-4-thiol derivatives were synthesized and evaluated on human cancer cell lines. Among them, compound 6p displayed potent and broad-spectrum anti-proliferative activities in vitro on some human cancer cell lines, even better than sorafenib. The advanced kinase inhibitory assays [...] Read more.
A novel series of N-methylpicolinamide-4-thiol derivatives were synthesized and evaluated on human cancer cell lines. Among them, compound 6p displayed potent and broad-spectrum anti-proliferative activities in vitro on some human cancer cell lines, even better than sorafenib. The advanced kinase inhibitory assays showed that compound 6p could selectively inhibit Aurora-B kinase. The biological results were rationalized by the molecular docking study, which indicated the stable interactions of 6p with the Aurora-B kinase. Full article
(This article belongs to the Section Medicinal Chemistry)
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287 KiB  
Article
Phenolics and Flavonoids Compounds, Phenylanine Ammonia Lyase and Antioxidant Activity Responses to Elevated CO2 in Labisia pumila (Myrisinaceae)
by Hawa Z.E. Jaafar, Mohd Hafiz Ibrahim and Ehsan Karimi
Molecules 2012, 17(6), 6331-6347; https://doi.org/10.3390/molecules17066331 - 25 May 2012
Cited by 57 | Viewed by 6323
Abstract
A split plot 3 × 3 experiment was designed to examine the impact of three concentrations of CO2 (400, 800 and 1,200 µmol·mol−1) on the phenolic and flavonoid compound profiles, phenylalanine ammonia lyase (PAL) and antioxidant activity in three varieties [...] Read more.
A split plot 3 × 3 experiment was designed to examine the impact of three concentrations of CO2 (400, 800 and 1,200 µmol·mol−1) on the phenolic and flavonoid compound profiles, phenylalanine ammonia lyase (PAL) and antioxidant activity in three varieties of Labisia pumila Benth. (var. alata, pumila and lanceolata) after 15 weeks of exposure. HPLC analysis revealed a strong influence of increased CO2 concentration on the modification of phenolic and flavonoid profiles, whose intensity depended on the interaction between CO2 levels and L. pumila varieties. Gallic acid and quercetin were the most abundant phenolics and flavonoids commonly present in all the varieties. With elevated CO2 (1,200 µmol·mol−1) exposure, gallic acid increased tremendously, especially in var. alata and pumila (101–111%), whilst a large quercetin increase was noted in var. lanceolata (260%), followed closely by alata (201%). Kaempferol, although detected under ambient CO2 conditions, was undetected in all varieties after exposure. Instead, caffeic acid was enhanced tremendously in var. alata (338~1,100%) and pumila (298~433%). Meanwhile, pyragallol and rutin were only seen in var. alata (810 µg·g−1 DW) and pumila (25 µg·g−1 DW), respectively, under ambient conditions; but the former compound went undetected in all varieties while rutin continued to increase by 262% after CO2 enrichment. Interestingly, naringenin that was present in all varieties under ambient conditions went undetected under enrichment, except for var. pumila where it was enhanced by 1,100%. PAL activity, DPPH and FRAP also increased with increasing CO2 levels implying the possible improvement of health-promoting quality of Malaysian L. pumila under high CO2 enrichment conditions. Full article
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1310 KiB  
Article
Zinc Phthalocyanine Labelled Polyethylene Glycol: Preparation, Characterization, Interaction with Bovine Serum Albumin and Near Infrared Fluorescence Imaging in Vivo
by Feng Lv, Bo Cao, Yanli Cui and Tianjun Liu
Molecules 2012, 17(6), 6348-6361; https://doi.org/10.3390/molecules17066348 - 25 May 2012
Cited by 66 | Viewed by 6261
Abstract
Zinc phthalocyanine labelled polyethylene glycol was prepared to track and monitor the in vivo fate of polyethylene glycol. The chemical structures were characterized by nuclear magnetic resonance and infrared spectroscopy. Their light stability and fluorescence quantum yield were evaluated by UV-Visible and fluorescence [...] Read more.
Zinc phthalocyanine labelled polyethylene glycol was prepared to track and monitor the in vivo fate of polyethylene glycol. The chemical structures were characterized by nuclear magnetic resonance and infrared spectroscopy. Their light stability and fluorescence quantum yield were evaluated by UV-Visible and fluorescence spectroscopy methods. The interaction of zinc phthalocyanine labelled polyethylene glycol with bovine serum albumin was evaluated by fluorescence titration and isothermal titration calorimetry methods. Optical imaging in vivo, organ aggregation as well as distribution of fluorescence experiments for tracking polyethylene glycol were performed with zinc phthalocyanine labelled polyethylene glycol as fluorescent agent. Results show that zinc phthalocyanine labelled polyethylene glycol has good optical stability and high emission ability in the near infrared region. Imaging results demonstrate that zinc phthalocyanine labelled polyethylene glycol can track and monitor the in vivo process by near infrared fluorescence imaging, which implies its potential in biomaterials evaluation in vivo by a real-time noninvasive method. Full article
(This article belongs to the Special Issue Tetrapyrroles, Porphyrins and Phthalocyanines)
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764 KiB  
Article
4-Thiazolidinones in Heterocyclic Synthesis: Synthesis of Novel Enaminones, Azolopyrimidines and 2-Arylimino-5-arylidene-4-thiazolidinones
by Haider Behbehani and Hamada Mohamed Ibrahim
Molecules 2012, 17(6), 6362-6385; https://doi.org/10.3390/molecules17066362 - 25 May 2012
Cited by 54 | Viewed by 11435
Abstract
The 4-thiazolidinones 3a–d were used as a key intermediates for the synthesis of 2-arylimino-5-arylidene-4-thiazolidinones derivatives 7a–p via nucleophilic addition reactions with the arylidene malononitrile. Moreover the 4-thiazolidinones 3a and 3c condensed with the DMF-DMA to form the corresponding enamines 8 and 9 depending [...] Read more.
The 4-thiazolidinones 3a–d were used as a key intermediates for the synthesis of 2-arylimino-5-arylidene-4-thiazolidinones derivatives 7a–p via nucleophilic addition reactions with the arylidene malononitrile. Moreover the 4-thiazolidinones 3a and 3c condensed with the DMF-DMA to form the corresponding enamines 8 and 9 depending on the reaction conditions. Otherwise the 4-thiazolidinone 3b reacts regioselectively with DMF-DMA to afford the enaminones 10 and 11, respectively. The latter reacts with many heterocyclic amines affording polyfunctionally substituted fused pyrimidine derivatives 13–18. The enamine 8b was also reacted with the 3-amino-1,2,4-triazole to afford the acyclic product 19, which could not be further cyclized to the corresponding tricyclic system 20. Moreover the 4-thiazolidinone 3c reacted with the benzenediazonium chloride to afford the arylhydrazones 12. The X-ray single crystal technique was employed in this study for structure elucidation and Z/E potential isomerism configuration determination. The X-ray crystallographic analyses of eight products could be obtained, thus establishing with certainty the structures proposed in this work. Full article
(This article belongs to the Section Organic Chemistry)
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180 KiB  
Article
Preparation of Quinolinium Salts Differing in the Length of the Alkyl Side Chain
by Jan Marek, Vladimir Buchta, Ondrej Soukup, Petr Stodulka, Jiri Cabal, Kallol K. Ghosh, Kamil Musilek and Kamil Kuca
Molecules 2012, 17(6), 6386-6394; https://doi.org/10.3390/molecules17066386 - 25 May 2012
Cited by 59 | Viewed by 5145
Abstract
Quaternary quinolinium salts differing in alkyl chain length are members of a widespread group of cationic surfactants. These compounds have numerous applications in various branches of industry and research. In this work, the preparation of quinoline-derived cationic surface active agents differing in the [...] Read more.
Quaternary quinolinium salts differing in alkyl chain length are members of a widespread group of cationic surfactants. These compounds have numerous applications in various branches of industry and research. In this work, the preparation of quinoline-derived cationic surface active agents differing in the length of the side alkyl chains (from C8 to C20) is described. An HPLC method was successfully developed for distinction of all members of the series of prepared long-chain quinolinium derivatives. In conclusion, some possibilities of intended tests or usage have been summarized. In vitro testing using a microdilution broth method showed good activity of a substance with a C12 chain length against Gram-positive cocci and Candida species. Full article
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234 KiB  
Article
Observation of 1,3-Diketones Formation in the Reaction of Bulky Acyl Chlorides with Methyllithium
by Jian Zhang, Nianfa Yang and Liwen Yang
Molecules 2012, 17(6), 6415-6423; https://doi.org/10.3390/molecules17066415 - 29 May 2012
Cited by 29 | Viewed by 5910
Abstract
The formation of 1,3-diketones was observed in the reactions of bulky acyl chlorides with methyllithium. The reaction products depend on the steric hindrance around the carbonyl group of the acyl chloride and the electronic effect of the group(s) linked to the carbonyl. When [...] Read more.
The formation of 1,3-diketones was observed in the reactions of bulky acyl chlorides with methyllithium. The reaction products depend on the steric hindrance around the carbonyl group of the acyl chloride and the electronic effect of the group(s) linked to the carbonyl. When the steric hindrance around the carbonyl group of the acyl chloride is big enough, the 1,3-diketone is the only product. In the case of the moderate hindrance around the carbonyl group of the acyl chloride, a moderate yield of 1,3-diketone is obtained and some tertiary alcohol is generated. When there is no steric hindrance around the carbonyl group of the acyl chloride, the tertiary alcohol is the only product. When the steric hindrance around the carbonyl group is moderate and an electron-donating group is connected to the carbonyl of the acyl chloride, all three products—ketone, 1,3-diketone and tertiary alcohol—can be isolated from the reaction mixture after long reaction times. Full article
(This article belongs to the Section Organic Chemistry)
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321 KiB  
Article
Two New Diterpenoids from the Buds of Wikstroemia chamaedaphne
by Jieru Guo, Jinwen Zhang, Penghua Shu, Lingmei Kong, Xincai Hao, Yongbo Xue, Zengwei Luo, Yan Li, Gao Li, Guangmin Yao and Yonghui Zhang
Molecules 2012, 17(6), 6424-6433; https://doi.org/10.3390/molecules17066424 - 29 May 2012
Cited by 13 | Viewed by 5464
Abstract
Two new diterpenoids, wikstroelide Q (1) and prostratin Q (5), together with three known diterpenoids, pimelea factors P2 (2), P3 (3), and prostratin (4), and five known lignans, (+)-epipioresinol (6 [...] Read more.
Two new diterpenoids, wikstroelide Q (1) and prostratin Q (5), together with three known diterpenoids, pimelea factors P2 (2), P3 (3), and prostratin (4), and five known lignans, (+)-epipioresinol (6), (+)-isolariciresinol (7), (−)-lariciresinol (8), (+)-epi-sesaminone (9), and prestegane B (10), were isolated from the buds of Wikstroemia chamaedaphne Meissn. Their structures were elucidated by a combination of spectroscopic analyses. Compounds 110 were evaluated for their cytotoxicities against HL-60, SMMC-7721, A549, MCF-7, SW480, and BEAS-2B cell lines in vitro. Full article
(This article belongs to the Section Natural Products Chemistry)
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266 KiB  
Article
Synthesis, Spectroscopy, Thermal Analysis, Magnetic Properties and Biological Activity Studies of Cu(II) and Co(II) Complexes with Schiff Base Dye Ligands
by Raziyeh Arab Ahmadi and Saeid Amani
Molecules 2012, 17(6), 6434-6448; https://doi.org/10.3390/molecules17066434 - 29 May 2012
Cited by 59 | Viewed by 6643
Abstract
Three azo group-containing Schiff base ligands, namely 1-{3-[(3-hydroxy-propylimino)methyl]-4-hydroxyphenylazo}-4-nitrobenzene (2a), 1-{3-[(3-hydroxypropyl-imino)methyl]-4-hydroxyphenylazo}-2-chloro-4-nitrobenzene (2b) and 1-{3-[(3-hydroxy-propylimino)methyl]-4-hydroxyphenylazo}-4-chloro-3-nitrobenzene (2c) were prepared. The ligands were characterized by elemental analysis, FTIR spectroscopy, UV-Vis spectroscopy, 13C- and 1H-NMR spectroscopy and thermogravimetric analysis. Next [...] Read more.
Three azo group-containing Schiff base ligands, namely 1-{3-[(3-hydroxy-propylimino)methyl]-4-hydroxyphenylazo}-4-nitrobenzene (2a), 1-{3-[(3-hydroxypropyl-imino)methyl]-4-hydroxyphenylazo}-2-chloro-4-nitrobenzene (2b) and 1-{3-[(3-hydroxy-propylimino)methyl]-4-hydroxyphenylazo}-4-chloro-3-nitrobenzene (2c) were prepared. The ligands were characterized by elemental analysis, FTIR spectroscopy, UV-Vis spectroscopy, 13C- and 1H-NMR spectroscopy and thermogravimetric analysis. Next the corresponding copper(II) and cobalt(II) metal complexes were synthesized and characterized by the physicochemical and spectroscopic methods of elemental analysis, FTIR spectroscopy, UV-Vis spectroscopy, magnetic moment measurements, and thermogravimetric analysis (TGA) and (DSC). The room temperature effective magnetic moments of complexes are 1.45, 1.56, 1.62, 2.16, 2.26 and 2.80 B.M. for complexes 3a, 3b, 3c, 4a 4b, and 4c, respectively, indicating that the complexes are paramagnetic with considerable electronic communication between the two metal centers. Full article
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331 KiB  
Article
The Coumarin Psoralidin Enhances Anticancer Effect of Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL)
by Joanna Bronikowska, Ewelina Szliszka, Dagmara Jaworska, Zenon P. Czuba and Wojciech Krol
Molecules 2012, 17(6), 6449-6464; https://doi.org/10.3390/molecules17066449 - 29 May 2012
Cited by 82 | Viewed by 7605
Abstract
Coumarins are a very common type of secondary plant metabolites with a broad spectrum of biological activities. Psoralidin is a naturally occurring furanocoumarin isolated from Psoralea corylifolia possessing anticancer and chemopreventive properties. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in cancer cells [...] Read more.
Coumarins are a very common type of secondary plant metabolites with a broad spectrum of biological activities. Psoralidin is a naturally occurring furanocoumarin isolated from Psoralea corylifolia possessing anticancer and chemopreventive properties. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in cancer cells with no toxicity toward normal tissues. Endogenous TRAIL plays an important role in immune surveillance and defence against cancer cells. Coumarins can modulate TRAIL-mediated apoptosis in cancer cells. We examined the cytotoxic and apoptotic activities of psoralidin in combination with TRAIL on HeLa cancer cells. The cytotoxicity was measured by MTT and LDH assays. The apoptosis was detected using annexin V-FITC staining and mitochondrial membrane potential was evaluated using DePsipher staining by fluorescence microscopy. Death receptor (TRAIL-R1/DR4 and TRAIL-R2/DR5) expression was analyzed using flow cytometry. Psoralidin enhanced TRAIL-induced apoptosis in HeLa cells through increased expression of TRAIL-R2 death receptor and depolarization of mitochondrial membrane potential. Our study indicated that psoralidin augmented the anticancer effects of TRAIL and confirmed a potential use of coumarins in cancer chemoprevention. Full article
(This article belongs to the Collection Bioactive Compounds)
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592 KiB  
Article
Influence of Chemical Extraction Conditions on the Physicochemical and Functional Properties of Polysaccharide Gum from Durian (Durio zibethinus) Seed
by Hamed Mirhosseini and Bahareh Tabatabaee Amid
Molecules 2012, 17(6), 6465-6480; https://doi.org/10.3390/molecules17066465 - 29 May 2012
Cited by 89 | Viewed by 7545
Abstract
Durian seed is an agricultural biomass waste of durian fruit. It can be a natural plant source of non-starch polysaccharide gum with potential functional properties. The main goal of the present study was to investigate the effect of chemical extraction variables (i.e [...] Read more.
Durian seed is an agricultural biomass waste of durian fruit. It can be a natural plant source of non-starch polysaccharide gum with potential functional properties. The main goal of the present study was to investigate the effect of chemical extraction variables (i.e., the decolouring time, soaking temperature and soaking time) on the physicochemical properties of durian seed gum. The physicochemical and functional properties of chemically-extracted durian seed gum were assessed by determining the particle size and distribution, solubility and the water- and oil-holding capacity (WHC and OHC). The present work revealed that the soaking time should be considered as the most critical extraction variable affecting the physicochemical properties of crude durian seed gum. Full article
(This article belongs to the Special Issue Natural Polysaccharides: Chemistry, Bioactivity and Analysis)
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198 KiB  
Article
Antioxidant and Immunity Activities of Fufang Kushen Injection Liquid
by Shen-Kang Zhou, Rui-Li Zhang, Yun-Feng Xu and Tie-Nan Bi
Molecules 2012, 17(6), 6481-6490; https://doi.org/10.3390/molecules17066481 - 30 May 2012
Cited by 56 | Viewed by 5086
Abstract
We investigated the effects of Fufang Kushen Injection Liquid (FFKSIL) on gastric immunity and oxidant-antioxidant status during N-methyl-N′-nitro-N-nitroso-guanidine (MNNG)-induced gastric carcinogenesis. The extent of lipid peroxidation and the levels of reduced glutathione (GSH) and activities of the GSH-dependent [...] Read more.
We investigated the effects of Fufang Kushen Injection Liquid (FFKSIL) on gastric immunity and oxidant-antioxidant status during N-methyl-N′-nitro-N-nitroso-guanidine (MNNG)-induced gastric carcinogenesis. The extent of lipid peroxidation and the levels of reduced glutathione (GSH) and activities of the GSH-dependent enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were used to monitor the peroxidative balance. Enhanced lipid peroxidation in the gastric cancer animals was accompanied by significant decreases in the activities of GSH, GPx, GST and GR. Administration of FFKSIL significantly enhanced serum IgA, IgG, IgM, IL-2, IL-4 and IL-10 levels, decreased serum IL-6 and TNF-α levels, lowered the levels of lipid peroxides and enhanced GSH levels and activities of GSH-dependent enzymes. Our results suggest that FFKSIL blocks experimental gastric carcinogenesis by protecting against carcinogen-induced oxidative damage and improving immunity activity. Full article
228 KiB  
Article
Variation in Minerals, Phenolics and Antioxidant Activity of Peel and Pulp of Different Varieties of Peach (Prunus persica L.) Fruit from Pakistan
by Maleeha Manzoor, Farooq Anwar, Zahed Mahmood, Umer Rashid and Muhammad Ashraf
Molecules 2012, 17(6), 6491-6506; https://doi.org/10.3390/molecules17066491 - 30 May 2012
Cited by 55 | Viewed by 8381
Abstract
Peach (Prunus persica L.), being a potential source of bioactive compounds, has been demonstrated to have medicinal benefits. In this study variation of minerals and antioxidant characteristics (total phenolic contents, total flavonoid contents, reducing power, inhibition of peroxidation using linoleic acid system [...] Read more.
Peach (Prunus persica L.), being a potential source of bioactive compounds, has been demonstrated to have medicinal benefits. In this study variation of minerals and antioxidant characteristics (total phenolic contents, total flavonoid contents, reducing power, inhibition of peroxidation using linoleic acid system and DPPH free radical scavenging activity) between peel and pulp parts of different peach varieties, namely Golden, Shireen, and Shahpasand were investigated. The peel and pulp extracts, derived from the varieties analyzed, exhibited an appreciable amount of total phenolics (TP) and total flavonoids (TF), ranging from 1,209.3–1,354.5, 711.7–881.3 mg GAE/100 g and 599.7–785.5, 301.3–499.7 mg CE/100 g on a dry weight basis, respectively. Reducing power of peel and pulp extracts (12.5 mg/mL concentration) ranged from 2.57–2.77 and 1.54–1.99.The inhibition of linoleic acid peroxidation and DPPH scavenging activity of the extracts varied from 70.8–80.9% and 66.8–76.5% in peels, and 51.9–60.1% and 43.4–49.1% in pulps. The mineral analysis revealed that the content of K was highest in both parts of the peach fruit followed by Mg, Ca, Fe, Mn and Zn. The results of our present study indicate that peach peel had significantly higher levels of minerals, antioxidant capacity and phenolics than those of the pulp, suggesting the intake of unpeeled peach as a potential source of high-value components. The peach peel can be a useful as a viable source of natural antioxidants for functional foods and nutraceutical applications. Full article
(This article belongs to the Section Medicinal Chemistry)
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274 KiB  
Article
Asymmetric Synthesis of the Carbon-14-Labeled Selective Glucocorticoid Receptor Modulator using Cinchona Alkaloid Catalyzed Addition of 6-Bromoindole to Ethyl Trifluoropyruvate
by Takaaki Sumiyoshi, Daisuke Urabe, Kengo Tojo, Masato Sakamoto, Kazumi Niidome, Norie Tsuboya, Tomoko Nakajima and Masanori Tobe
Molecules 2012, 17(6), 6507-6518; https://doi.org/10.3390/molecules17066507 - 30 May 2012
Cited by 67 | Viewed by 5285
Abstract
We describe in this study the asymmetric synthesis of radioisotope (RI)-labeled selective glucocorticoid receptor modulator. This synthesis is based on optimization of the cinchona alkaloid catalyzed addition of 6-bromoindole to ethyl trifluoropyruvate and Negishi coupling of zinc cyanide to the 6-bromoindole moiety. [ [...] Read more.
We describe in this study the asymmetric synthesis of radioisotope (RI)-labeled selective glucocorticoid receptor modulator. This synthesis is based on optimization of the cinchona alkaloid catalyzed addition of 6-bromoindole to ethyl trifluoropyruvate and Negishi coupling of zinc cyanide to the 6-bromoindole moiety. [14C] Labeled (−)-{4-[(1-{2-[6-cyano-1-(cyclohexylmethyl)-1H-indol-3-yl]-3,3,3-trifluoro-2-hydroxypropyl}piperidin-4-yl)oxy]-3-methoxyphenyl}acetic acid (−)-1 was synthesized successfully with high enantioselectivity ( > 99% ee) and sufficient radiochemical purity. Full article
(This article belongs to the Special Issue Organocatalysis)
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491 KiB  
Article
Development of Diversified Methods for Chemical Modification of the 5,6-Double Bond of Uracil Derivatives Depending on Active Methylene Compounds
by Hironao Sajiki, Yusuke Iida, Kanoko Ikawa, Yoshinari Sawama, Yasunari Monguchi, Yukio Kitade, Yoshifumi Maki, Hideo Inoue and Kosaku Hirota
Molecules 2012, 17(6), 6519-6546; https://doi.org/10.3390/molecules17066519 - 30 May 2012
Cited by 3 | Viewed by 7919
Abstract
The reaction of 5-halogenouracil and uridine derivatives 1 and 7 with active methylene compounds under basic conditions produced diverse and selective C-C bond formation products by virtue of the nature of the carbanions. Three different types of reactions such as the regioselective C-C [...] Read more.
The reaction of 5-halogenouracil and uridine derivatives 1 and 7 with active methylene compounds under basic conditions produced diverse and selective C-C bond formation products by virtue of the nature of the carbanions. Three different types of reactions such as the regioselective C-C bond formation at the 5- and 6-positions of uracil and uridine derivatives (products 2, 5, 8, 17, 20 and 21), and the formation of fused heterocycle derivatives 2,4-diazabicyclo[4.1.0]heptane (15) and 2,4-diazabicyclo-[4.1.0]nonane (16) via dual C-C bond formations at both the 5- and 6-positions were due to the different active methylene compounds used as reagents. Full article
(This article belongs to the Special Issue Nucleic Acid Analogs)
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361 KiB  
Article
Condensation Reactions of 3-Oxo-2-arylhydrazonopropanals with Active Methylene Reagents: Formation of 2-Hydroxy- and 2-Amino-6-substituted-5-arylazonicotinates and Pyrido[3,2-c]cinnolines via 6π-Electrocyclization Reactions
by Saleh M. Al-Mousawi and Morsy A. El-Apasery
Molecules 2012, 17(6), 6547-6556; https://doi.org/10.3390/molecules17066547 - 30 May 2012
Cited by 12 | Viewed by 5024
Abstract
3-Oxo-3-phenyl-2-(p-tolylhydrazono)propanal (1a) undergoes condensation with ethyl cyanoacetate in acetic acid in the presence of ammonium acetate to yield either 2-hydroxy-6-phenyl-5-p-tolylazonicotinic acid ethyl ester (6a) or 2-amino-6-phenyl-5-p-tolyl-azonicotinic acid ethyl ester (8), depending [...] Read more.
3-Oxo-3-phenyl-2-(p-tolylhydrazono)propanal (1a) undergoes condensation with ethyl cyanoacetate in acetic acid in the presence of ammonium acetate to yield either 2-hydroxy-6-phenyl-5-p-tolylazonicotinic acid ethyl ester (6a) or 2-amino-6-phenyl-5-p-tolyl-azonicotinic acid ethyl ester (8), depending on the reaction conditions. Similarly, other 3-oxo-3-aryl-2-arylhydrazonopropanals 1a,b condense with active methylene nitriles 2c,d to yield arylazonicotinates 6b,c. In contrast, 2-[(4-nitrophenyl)-hydrazono]-3-oxo-3-phenyl-propanal (1c) reacts with ethyl cyanoacetate to yield ethyl 6-(4-nitrophenyl)-2-oxo-2,6-dihydropyrido[3,2–c]cinnoline-3-carboxylate (11), via a novel 6π-electrocyclization pathway. Finally, 3-oxo-2-(phenylhydrazono)-3-p-tolylpropanal (1d) condenses with 2a–c to yield pyridazinones 13a–c. Full article
(This article belongs to the Section Organic Chemistry)
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829 KiB  
Article
Maturation of Murine Bone Marrow-Derived Dendritic Cells Induced by Radix Glycyrrhizae Polysaccharide
by Xiaobing Li, Xiaojuan He, Biao Liu, Li Xu, Cheng Lu, Hongyan Zhao, Xuyan Niu, Shilin Chen and Aiping Lu
Molecules 2012, 17(6), 6557-6568; https://doi.org/10.3390/molecules17066557 - 30 May 2012
Cited by 29 | Viewed by 6512
Abstract
Radix Glycyrrhizae polysaccharide (GP), the most important component of Radix Glycyrrhizae, has been reported to have many immunopharmacological activities. However, the mechanism by which GP affects dendritic cells (DCs) has not been elucidated. In this study, we investigated the effect of GP [...] Read more.
Radix Glycyrrhizae polysaccharide (GP), the most important component of Radix Glycyrrhizae, has been reported to have many immunopharmacological activities. However, the mechanism by which GP affects dendritic cells (DCs) has not been elucidated. In this study, we investigated the effect of GP on murine bone marrow-derived DCs and the potential pathway through which GP exerts this effect. Mononuclear cells (MNCs) were isolated from murine bone marrow and induced to become DCs by culturing with GM-CSF and IL-4. Six days later, DCs were divided into three groups: control group, GP group and LPS group. After 48 h of treatment, phenotypic figures and antigen uptake ability were determined by FACS analysis. The proliferation of DC-stimulated allogenic CD3+ T cells was detected by WST-1. IL-12 p70 and IFN-γ, which are secreted by DCs and CD3+ T cells respectively, were quantified by ELISA. Additionally, IL-12 p40 mRNA expression was determined by real-time PCR. Alterations in TLR4-related signaling pathways were examined by performing an antibody neutralization experiment. Treatment of DCs with GP resulted in the enhanced expression of the cell surface molecules CD80, CD86 and MHC I-A/I-E. GP also increased the production of IL-12 p70 by DCs in a time-dependent manner. The endocytosis of FITC-dextran by DCs was suppressed by GP administration. Furthermore, GP-treated DCs enhanced both the proliferation and IFN-γ secretion of allogenic CD3+ T cells. Finally, the effects of GP on DCs were partially reduced by using inhibitors of TLR4, NF-κB, p38 MAPK or JNK. In conclusion, GP can induce the maturation of DCs, and does so, in part, by regulating a TLR4-related signaling pathway. Full article
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598 KiB  
Article
Identification and Antibacterial Evaluation of Bioactive Compounds from Garcinia kola (Heckel) Seeds
by Christinah T. Seanego and Roland N. Ndip
Molecules 2012, 17(6), 6569-6584; https://doi.org/10.3390/molecules17066569 - 31 May 2012
Cited by 36 | Viewed by 6222
Abstract
We assessed the bioactivity of G. kola seeds on Streptococcus pyogenes, Staphylococcus aureus, Plesiomonas shigelloides and Salmonella typhimurium. The crude ethyl acetate, ethanol, methanol, acetone and aqueous extracts were screened by the agar-well diffusion method and their activities were further [...] Read more.
We assessed the bioactivity of G. kola seeds on Streptococcus pyogenes, Staphylococcus aureus, Plesiomonas shigelloides and Salmonella typhimurium. The crude ethyl acetate, ethanol, methanol, acetone and aqueous extracts were screened by the agar-well diffusion method and their activities were further determined by Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays. The extracts were fractionated by Thin Layer Chromatography (TLC). Bioautography was used to assess the activity of the possible classes of compounds present in the more active extracts. Column chromatography was used to purify the active compounds from the mixture, while GC-MS was used to identify the phytocomponents of the fractions. The inhibition zone diameters of the extracts ranged from 0–24 ± 1.1 mm, while MIC and MBC values ranged between 0.04–1.25 mg/mL and 0.081–2.5 mg/mL, respectively. The chloroform/ethyl acetate/formic acid (CEF) solvent system separated more active compounds. The MIC of the fractions ranged between 0.0006–2.5 mg/mL. CEF 3 (F3), CEF 11 (F11) and CEF 12 (F12) revealed the presence of high levels of linoleic acid, 1,2-benzenedicarboxylic acid and 2,3-dihydro-3,5-dihydroxy-6-methyl ester, respectively. The results obtained from this study justify the use of this plant in traditional medicine and provide leads which could be further exploited for the development of new and potent antimicrobials. Full article
(This article belongs to the Section Natural Products Chemistry)
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200 KiB  
Article
A New Butanolide Compound from the Aerial Part of Lindera akoensis with Anti-inflammatory Activity
by Chung-Ping Yang, Guan-Jhong Huang, Hui-Chi Huang, Yu-Chang Chen, Chi-I Chang, Sheng-Yang Wang, Ih-Sheng Chen, Yen-Hsueh Tseng, Shih-Chang Chien and Yueh-Hsiung Kuo
Molecules 2012, 17(6), 6585-6592; https://doi.org/10.3390/molecules17066585 - 31 May 2012
Cited by 39 | Viewed by 4870
Abstract
A new butanolide, 3b-((E)-dodec-1-enyl)-4b-hydroxy-5b-methyldihydrofuran-2-one (1) and four known butanolides: Akolactone A (2), (3Z,4a,5b)-3-(dodec-11-enylidene)-4-hydroxy-5-methylbutalactone (3), (3E,4a,5b)-3-(dodec-11-enylidene)-4-hydroxy-5-methylbutalactone (4) and dihydroisoobtusilactone (5), were isolated from the aerial parts of Lindera [...] Read more.
A new butanolide, 3b-((E)-dodec-1-enyl)-4b-hydroxy-5b-methyldihydrofuran-2-one (1) and four known butanolides: Akolactone A (2), (3Z,4a,5b)-3-(dodec-11-enylidene)-4-hydroxy-5-methylbutalactone (3), (3E,4a,5b)-3-(dodec-11-enylidene)-4-hydroxy-5-methylbutalactone (4) and dihydroisoobtusilactone (5), were isolated from the aerial parts of Lindera akoensis. These butanolides showed in vitro anti-inflammatory activity decrease the LPS-stimulated production of nitrite in RAW264.7 cell, with IC50 values of 1.4–179.9 mM. Full article
(This article belongs to the Section Natural Products Chemistry)
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625 KiB  
Article
Acrylate Functionalized Tetraalkylammonium Salts with Ionic Liquid Properties
by Dorian C. Grothe, Wolfdietrich Meyer and Silvia Janietz
Molecules 2012, 17(6), 6593-6604; https://doi.org/10.3390/molecules17066593 - 31 May 2012
Cited by 20 | Viewed by 5396
Abstract
Acrylate functionalized ionic liquids based on tetraalkylammonium salts with terminal acrylates- and methylacrylates were synthesized. Melting points and ionic conductivity of twenty compounds in six groups were determined. Within one group the effect of three different counterions was investigated and discussed. The groups [...] Read more.
Acrylate functionalized ionic liquids based on tetraalkylammonium salts with terminal acrylates- and methylacrylates were synthesized. Melting points and ionic conductivity of twenty compounds in six groups were determined. Within one group the effect of three different counterions was investigated and discussed. The groups differ in cationic structure elements because of their functional groups such as acrylate and methacrylate, alkyl residues at the nitrogen and number of quaternary ammonium atoms within the organic cation. The effect of these cationic structure elements has been examined concerning the compiled parameters with a view to qualifying them as components for solid state electrolytes. The newly synthesized ionic liquids were characterized by NMR and FTIR analysis. The exchange of halide ions like bromide as counter ions to weakly coordinating [PF6], [OTf] or [TFSI] reduces the melting points significantly and leads to an ion conductivity of about 10−4 S/cm at room temperature. In the case of the dicationic ionic liquid, an ion conductivity of about 10−3 S/cm was observed. Full article
(This article belongs to the Section Organic Chemistry)
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402 KiB  
Article
Reversible Low-Light Induced Photoswitching of Crowned Spiropyran-DO3A Complexed with Gadolinium(III) Ions
by Klaus Kruttwig, Diego R. Yankelevich, Chantal Brueggemann, Chuqiao Tu, Noelle L’Etoile, André Knoesen and Angelique Y. Louie
Molecules 2012, 17(6), 6605-6624; https://doi.org/10.3390/molecules17066605 - 31 May 2012
Cited by 13 | Viewed by 6791
Abstract
Photoswitchable spiropyran has been conjugated to the crowned ring system DO3A, which improves its solubility in dipolar and polar media and stabilizes the merocyanine isomer. Adding the lanthanide ion gadolinium(III) to the macrocyclic ring system leads to a photoresponsive magnetic resonance imaging contrast [...] Read more.
Photoswitchable spiropyran has been conjugated to the crowned ring system DO3A, which improves its solubility in dipolar and polar media and stabilizes the merocyanine isomer. Adding the lanthanide ion gadolinium(III) to the macrocyclic ring system leads to a photoresponsive magnetic resonance imaging contrast agent that displays an increased spin-lattice relaxation time (T1) upon visible light stimulation. In this work, the photoresponse of this photochromic molecule to weak light illumination using blue and green light emitting diodes was investigated, simulating the emission spectra from bioluminescent enzymes. Photon emission rate of the light emitting diodes was changed, from 1.75 × 1016 photons·s−1 to 2.37 × 1012 photons·s−1. We observed a consistent visible light-induced isomerization of the merocyanine to the spiropyran form with photon fluxes as low as 2.37 × 1012 photons·s−1 resulting in a relaxivity change of the compound. This demonstrates the potential for use of the described imaging probes in low light level applications such as sensing bioluminescence enzyme activity. The isomerization behavior of gadolinium(III)-ion complexed and non-complexed spiropyran-DO3A was analyzed in water and ethanol solution in response to low light illumination and compared to the emitted photon emission rate from over-expressed Gaussia princeps luciferase. Full article
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247 KiB  
Article
Reaction of Iodonium Ylides of 1,3-Dicarbonyl Compounds with HF Reagents
by Keisuke Gondo and Tsugio Kitamura
Molecules 2012, 17(6), 6625-6632; https://doi.org/10.3390/molecules17066625 - 31 May 2012
Cited by 18 | Viewed by 6669
Abstract
Reaction of dibenzoylmethane with (diacetoxyiodo)benzene in the presence of KOH in MeCN quantitatively gave the corresponding iodonium ylide, which was treated with a HF reagent to afford the corresponding 2-fluorinated dibenzoylmethane in 14–50% yields. The similar reaction of the iodonium ylides obtained from [...] Read more.
Reaction of dibenzoylmethane with (diacetoxyiodo)benzene in the presence of KOH in MeCN quantitatively gave the corresponding iodonium ylide, which was treated with a HF reagent to afford the corresponding 2-fluorinated dibenzoylmethane in 14–50% yields. The similar reaction of the iodonium ylides obtained from 1-phenylbutan-1,3-dione, ethyl benzoylacetate, and ethyl p-nitrobenzoylacetate with TEA·3HF gave the corresponding fluorinated products in 17–34% yields. It is suggested that the fluorinated products were formed through the C-protonation of the ylide, followed by displacement with fluoride ion. The same reaction of the iodonium ylide of dibenzoylmethane with concentrated HCl gave the corresponding chlorinated product in 45% yield. Full article
(This article belongs to the Special Issue Hypervalent Compounds)
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5002 KiB  
Article
Aqueous Fraction of Nephelium ramboutan-ake Rind Induces Mitochondrial-Mediated Apoptosis in HT-29 Human Colorectal Adenocarcinoma Cells
by Chim Kei Chan, Bey Hing Goh, Muhamad Noor Alfarizal Kamarudin and Habsah Abdul Kadir
Molecules 2012, 17(6), 6633-6657; https://doi.org/10.3390/molecules17066633 - 31 May 2012
Cited by 19 | Viewed by 6518
Abstract
The aim of this study was to investigate the cytotoxic and apoptotic effects of Nephelium ramboutan-ake (pulasan) rind in selected human cancer cell lines. The crude ethanol extract and fractions (ethyl acetate and aqueous) of N. ramboutan-ake inhibited the growth of HT-29, HCT-116, [...] Read more.
The aim of this study was to investigate the cytotoxic and apoptotic effects of Nephelium ramboutan-ake (pulasan) rind in selected human cancer cell lines. The crude ethanol extract and fractions (ethyl acetate and aqueous) of N. ramboutan-ake inhibited the growth of HT-29, HCT-116, MDA-MB-231, Ca Ski cells according to MTT assays. The N. ramboutan-ake aqueous fraction (NRAF) was found to exert the greatest cytotoxic effect against HT-29 in a dose-dependent manner. Evidence of apoptotic cell death was revealed by features such as chromatin condensation, nuclear fragmentation and apoptotic body formation. The result from a TUNEL assay strongly suggested that NRAF brings about DNA fragmentation in HT-29 cells. Phosphatidylserine (PS) externalization on the outer leaflet of plasma membranes was detected with annexin V-FITC/PI binding, confirming the early stage of apoptosis. The mitochondrial permeability transition is an important step in the induction of cellular apoptosis, and the results clearly suggested that NRAF led to collapse of mitochondrial transmembrane potential in HT-29 cells. This attenuation of mitochondrial membrane potential (Δψm) was accompanied by increased production of ROS and depletion of GSH, an increase of Bax protein expression, and induced-activation of caspase-3/7 and caspase-9. These combined results suggest that NRAF induces mitochondrial-mediated apoptosis. Full article
(This article belongs to the Section Natural Products Chemistry)
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696 KiB  
Article
Application of Paramagnetic NMR-Validated Molecular Dynamics Simulation to the Analysis of a Conformational Ensemble of a Branched Oligosaccharide
by Ying Zhang, Sayoko Yamamoto, Takumi Yamaguchi and Koichi Kato
Molecules 2012, 17(6), 6658-6671; https://doi.org/10.3390/molecules17066658 - 31 May 2012
Cited by 36 | Viewed by 7013
Abstract
Oligosaccharides of biological importance often exhibit branched covalent structures and dynamic conformational multiplicities. Here we report the application of a method that we developed, which combined molecular dynamics (MD) simulations and lanthanide-assisted paramagnetic NMR spectroscopy, to evaluate the dynamic conformational ensemble of a [...] Read more.
Oligosaccharides of biological importance often exhibit branched covalent structures and dynamic conformational multiplicities. Here we report the application of a method that we developed, which combined molecular dynamics (MD) simulations and lanthanide-assisted paramagnetic NMR spectroscopy, to evaluate the dynamic conformational ensemble of a branched oligosaccharide. A lanthanide-chelating tag was attached to the reducing end of the branched tetrasaccharide of GM2 ganglioside to observe pseudocontact shifts as the source of long distance information for validating the conformational ensemble derived from MD simulations. By inspecting the results, the conformational space of the GM2 tetrasaccharide was compared with that of its nonbranched derivative, the GM3 trisaccharide. Full article
(This article belongs to the Special Issue Advances in Carbohydrate Chemistry 2012)
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199 KiB  
Article
Edible Flowers—A New Promising Source of Mineral Elements in Human Nutrition
by Otakar Rop, Jiri Mlcek, Tunde Jurikova, Jarmila Neugebauerova and Jindriska Vabkova
Molecules 2012, 17(6), 6672-6683; https://doi.org/10.3390/molecules17066672 - 31 May 2012
Cited by 175 | Viewed by 16912
Abstract
On a global scale, people are demanding more attractive and tasty food. Both the quality of foodstuffs and aesthetic aspects contribute to the appearance of consumed meals. The attraction and appeal of individual dishes could be enhanced by edible flowers. New information concerning [...] Read more.
On a global scale, people are demanding more attractive and tasty food. Both the quality of foodstuffs and aesthetic aspects contribute to the appearance of consumed meals. The attraction and appeal of individual dishes could be enhanced by edible flowers. New information concerning the composition and nutritional value of edible flowers is also important and represents a sufficient reason for their consumption. The aim of this study is to contribute to the popularization of some selected edible flowers of ornamental plants involving altogether 12 species. The flowers were used to determine their antioxidant capacity, which fluctuated between 4.21 and 6.96 g of ascorbic acid equivalents (AAE)/kg of fresh mass (FM). Correlation coefficients between antioxidant capacity and the contents of total phenolics and flavonoids were r2 = 0.9705 and r2 = 0.7861, respectively. Moreover, the results were supplemented with new data about the mineral composition of edible flowers (mostly, not found in the available literature). The highest levels of mineral elements were observed in the flowers of species Chrysanthemum, Dianthus or Viola. The most abundant element was potassium, the content of which ranged from 1,842.61 to 3,964.84 mg/kg of FM. Full article
(This article belongs to the Section Natural Products Chemistry)
246 KiB  
Article
Synthesis and Antibacterial Activity of Some Heterocyclic Chalcone Analogues Alone and in Combination with Antibiotics
by Thanh-Dao Tran, Thi-Thao-Nhu Nguyen, Tuong-Ha Do, Thi-Ngoc-Phuong Huynh, Cat-Dong Tran and Khac-Minh Thai
Molecules 2012, 17(6), 6684-6696; https://doi.org/10.3390/molecules17066684 - 01 Jun 2012
Cited by 91 | Viewed by 12825
Abstract
A series of simple heterocyclic chalcone analogues have been synthesized by Claisen Schmidt condensation reactions between substituted benzaldehydes and heteroaryl methyl ketones and evaluated for their antibacterial activity. The structures of the synthesized chalcones were established by IR and 1H-NMR analysis. The [...] Read more.
A series of simple heterocyclic chalcone analogues have been synthesized by Claisen Schmidt condensation reactions between substituted benzaldehydes and heteroaryl methyl ketones and evaluated for their antibacterial activity. The structures of the synthesized chalcones were established by IR and 1H-NMR analysis. The biological data shows that compounds p5, f6 and t5 had strong activities against both susceptible and resistant Staphylococcus aureus strains, but not activity against a vancomycin and methicillin resistant Staphylococcus aureus isolated from a human sample. The structure and activity relationships confirmed that compounds f5, f6 and t5 are potential candidates for future drug discovery and development. Full article
(This article belongs to the Special Issue ECSOC-15)
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180 KiB  
Article
Simple, Rapid and Reliable Preparation of [11C]-(+)-a-DTBZ of High Quality for Routine Applications
by Jinming Zhang, Xiaojun Zhang, Yungang Li and Jiahe Tian
Molecules 2012, 17(6), 6697-6704; https://doi.org/10.3390/molecules17066697 - 01 Jun 2012
Cited by 98 | Viewed by 4569
Abstract
[11C]-(+)-a-DTBZ has been used as a marker of dopaminergic terminal densities in human striatum and expressed in islet beta cells in the pancreas. We aimed to establish a fully automated and simple procedure for the synthesis of [11C]-(+)-a-DTBZ for [...] Read more.
[11C]-(+)-a-DTBZ has been used as a marker of dopaminergic terminal densities in human striatum and expressed in islet beta cells in the pancreas. We aimed to establish a fully automated and simple procedure for the synthesis of [11C]-(+)-a-DTBZ for routine applications. [11C]-(+)-a-DTBZ was synthesized from a 9-hydroxy precursor in acetone and potassium hydroxide with [11C]-methyl triflate and was purified by solid phase extraction using a Vac tC-18 cartridge. Radiochemical yields based on [11C]-methyl triflate (corrected for decay) were 82.3% ± 3.6%, with a specific radioactivity of 60 GBq/mmol. Time elapsed was less than 20 min from end of bombardment to release of the product for quality control. Full article
(This article belongs to the Section Medicinal Chemistry)
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469 KiB  
Article
Calculation of the Stabilization Energies of Oxidatively Damaged Guanine Base Pairs with Guanine
by Masayo Suzuki, Katsuhito Kino, Masayuki Morikawa, Takanobu Kobayashi, Rie Komori and Hiroshi Miyazawa
Molecules 2012, 17(6), 6705-6715; https://doi.org/10.3390/molecules17066705 - 01 Jun 2012
Cited by 19 | Viewed by 5970
Abstract
DNA is constantly exposed to endogenous and exogenous oxidative stresses. Damaged DNA can cause mutations, which may increase the risk of developing cancer and other diseases. G:C-C:G transversions are caused by various oxidative stresses. 2,2,4-Triamino-5(2H)-oxazolone (Oz), guanidinohydantoin (Gh)/iminoallantoin (Ia) and spiro-imino-dihydantoin [...] Read more.
DNA is constantly exposed to endogenous and exogenous oxidative stresses. Damaged DNA can cause mutations, which may increase the risk of developing cancer and other diseases. G:C-C:G transversions are caused by various oxidative stresses. 2,2,4-Triamino-5(2H)-oxazolone (Oz), guanidinohydantoin (Gh)/iminoallantoin (Ia) and spiro-imino-dihydantoin (Sp) are known products of oxidative guanine damage. These damaged bases can base pair with guanine and cause G:C-C:G transversions. In this study, the stabilization energies of these bases paired with guanine were calculated in vacuo and in water. The calculated stabilization energies of the Ia:G base pairs were similar to that of the native C:G base pair, and both bases pairs have three hydrogen bonds. By contrast, the calculated stabilization energies of Gh:G, which form two hydrogen bonds, were lower than the Ia:G base pairs, suggesting that the stabilization energy depends on the number of hydrogen bonds. In addition, the Sp:G base pairs were less stable than the Ia:G base pairs. Furthermore, calculations showed that the Oz:G base pairs were less stable than the Ia:G, Gh:G and Sp:G base pairs, even though experimental results showed that incorporation of guanine opposite Oz is more efficient than that opposite Gh/Ia and Sp. Full article
(This article belongs to the Special Issue ECSOC-15)
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300 KiB  
Article
1H-Nuclear Magnetic Resonance Analysis of the Triacylglyceride Composition of Cold-Pressed Oil from Camellia japonica
by Carmen Salinero, Xesús Feás, J. Pedro Mansilla, Julio A. Seijas, M. Pilar Vázquez-Tato, Pilar Vela and María J. Sainz
Molecules 2012, 17(6), 6716-6727; https://doi.org/10.3390/molecules17066716 - 04 Jun 2012
Cited by 29 | Viewed by 6846
Abstract
Camellia japonica (CJ) has oil-rich seeds, but the study of these oils has received little attention and has mainly focused only on their health properties. In the present work the relative composition of the fatty acid (FA) components of the triglycerides in cold-pressed [...] Read more.
Camellia japonica (CJ) has oil-rich seeds, but the study of these oils has received little attention and has mainly focused only on their health properties. In the present work the relative composition of the fatty acid (FA) components of the triglycerides in cold-pressed oil from CJ is studied by 1H-NMR. The results obtained were: 75.75%, 6.0%, 0.17% and 18.67%, for oleic, linoleic, linolenic and saturated FA respectively. Levels of C18 unsaturated FA found in CJ oil were similar to those reported for olive oils. We also checked the possibility of using 13C-NMR spectroscopy; however, the results confirmed the drawback of 13C over 1H-NMR for the study of FA components of CJ triglycerides due to its low gyromagnetic ratio and its very low natural abundance. Full article
(This article belongs to the Special Issue ECSOC-15)
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328 KiB  
Article
Short and Long-Term Effects of Baccharis articulata on Glucose Homeostasis
by Virginia D. Kappel, Danielle F. Pereira, Luisa H. Cazarolli, Samantha M. Guesser, Carlos H. Blum Da Silva, Eloir P. Schenkel, Flávio H. Reginatto and Fátima R. M. B. Silva
Molecules 2012, 17(6), 6754-6768; https://doi.org/10.3390/molecules17066754 - 04 Jun 2012
Cited by 69 | Viewed by 5399
Abstract
In this study, the in vivo effect of the crude extract and n-butanol and aqueous residual fractions of Baccharis articulata (Lam.) Pers. on serum glucose levels, insulin secretion and liver and muscle glycogen content, as well as in vitro action on serum [...] Read more.
In this study, the in vivo effect of the crude extract and n-butanol and aqueous residual fractions of Baccharis articulata (Lam.) Pers. on serum glucose levels, insulin secretion and liver and muscle glycogen content, as well as in vitro action on serum intestinal disaccharidase activity and albumin glycation were investigated. Oral administration of the extract and fractions reduced glycemia in hyperglycemic rats. Additionally, the n-butanol fraction, which has high flavonoids content, stimulated insulin secretion, exhibiting an insulinogenic index similar to that of glipizide. Also, the n-butanol fraction treatment significantly increased glycogen content in both liver and muscle tissue. In vitro incubation with the crude extract and n-butanol and aqueous residual fractions inhibited maltase activity and the formation of advanced glycation end-products (AGEs). Thus, the results demonstrated that B. articulata exhibits a significant antihyperglycemic and insulin-secretagogue role. These effects on the regulation of glucose homeostasis observed for B. articulata indicate potential anti-diabetic properties. Full article
(This article belongs to the Section Natural Products Chemistry)
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394 KiB  
Article
Response Surface Optimized Ultrasonic-Assisted Extraction of Flavonoids from Sparganii Rhizoma and Evaluation of Their in Vitro Antioxidant Activities
by Xinsheng Wang, Qinan Wu, Yanfang Wu, Guangyun Chen, Wei Yue and Qiaoli Liang
Molecules 2012, 17(6), 6769-6783; https://doi.org/10.3390/molecules17066769 - 04 Jun 2012
Cited by 62 | Viewed by 6363
Abstract
An efficient ultrasound-assisted extraction technique was employed to extract total flavonoids from Sparganii rhizoma. The optimum extraction conditions for the highest yield of total flavonoids were ethanol concentration 53.62%, ultrasonication time 29.41 min and ultrasound power 300 W, which were determined using response [...] Read more.
An efficient ultrasound-assisted extraction technique was employed to extract total flavonoids from Sparganii rhizoma. The optimum extraction conditions for the highest yield of total flavonoids were ethanol concentration 53.62%, ultrasonication time 29.41 min and ultrasound power 300 W, which were determined using response surface methodology. The extraction yields of the optimal ultrasound-assisted extraction were higher than using conventional extraction. The crude extract was then purified on a polyamide resin, whereby the flavonoids content in the purified extract increased to 94.62%. The antioxidant activities of the purified flavonoids including DPPH radical scavenging activity, ABTS+ radical scavenging activity, reducing power, hydroxyl radical scavenging activity and superoxide anion scavenging activity, were evaluated in vitro, which suggested that the flavonoids showed significant antioxidant activities. Rutin, kaempferol and formononetin were identified in the extract by comparing relative retention times and UV-Vis spectra with those of reference standards. Full article
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302 KiB  
Article
Improved Methods for Thermal Rearrangement of Alicyclic α-Hydroxyimines to α-Aminoketones: Synthesis of Ketamine Analogues as Antisepsis Candidates
by Hagit Elhawi, Hadar Eini, Amos Douvdevani and Gerardo Byk
Molecules 2012, 17(6), 6784-6807; https://doi.org/10.3390/molecules17066784 - 04 Jun 2012
Cited by 70 | Viewed by 9939
Abstract
Ketamine is an analgesic/anesthetic drug, which, in combination with other drugs, has been used as anesthetic for over 40 years. Ketamine induces its analgesic activities by blocking the N-methyl-D-aspartate (NMDA) receptor in the central nervous system (CNS). We have reported that low [...] Read more.
Ketamine is an analgesic/anesthetic drug, which, in combination with other drugs, has been used as anesthetic for over 40 years. Ketamine induces its analgesic activities by blocking the N-methyl-D-aspartate (NMDA) receptor in the central nervous system (CNS). We have reported that low doses of ketamine administrated to patients before incision significantly reduced post-operative inflammation as reflected by reduced interleukin-6 (IL-6) sera-levels. Our data demonstrated in a rat model of Gram-negative bacterial-sepsis that if we inject a low dose of ketamine following bacterial inoculation we reduce mortality from approximately 75% to 25%. Similar to what we have observed in operated patients, the levels of TNF-α and IL-6 in ketamine-treated rats were significantly lower than in septic animals not treated with ketamine. On the base of these results, we have designed and synthesized series of new analogues of ketamine applying a thermal rearrangement of alicyclic α-hydroxyimines to a-aminoketones in parallel arrays. One of the analogues (compound 6e) displayed high activity in down-regulating the levels of IL-6 and TNF-α in vivo as compared to ketamine. Full article
(This article belongs to the Collection Bioactive Compounds)
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448 KiB  
Article
Synthesis, Radiolabeling and Biological Evaluation of Propylene Amine Oxime Complexes Containing Nitrotriazoles as Hypoxia Markers
by Huafan Huang, Lei Mei and Taiwei Chu
Molecules 2012, 17(6), 6808-6820; https://doi.org/10.3390/molecules17066808 - 04 Jun 2012
Cited by 13 | Viewed by 4932
Abstract
Two propylene amine oxime (PnAO) complexes, 1, containing a 3-nitro-1,2,4-triazole and 2, containing two 3-nitro-1,2,4-triazoles, were synthesized and radiolabeled with 99mTc in high labeling yields. Cellular uptakes of 99mTc-1 and 99mTc-2 were tested using a S180 [...] Read more.
Two propylene amine oxime (PnAO) complexes, 1, containing a 3-nitro-1,2,4-triazole and 2, containing two 3-nitro-1,2,4-triazoles, were synthesized and radiolabeled with 99mTc in high labeling yields. Cellular uptakes of 99mTc-1 and 99mTc-2 were tested using a S180 cells line. Under anoxic conditions, the cellular uptakes of 99mTc-1 and 99mTc-2 were 33.7 ± 0.2% and 35.0 ± 0.7% at 4 h, whereas the normoxic uptakes of the two complexes were 6.0 ± 1.6% and 4.6 ± 0.9%, respectively. Both 99mTc-1 and 99mTc-2 displayed significant anoxic/normoxic differentials. The cellular uptakes were highly dependent on oxygen and temperature. Biodistribution studies revealed that both 99mTc-1 and 99mTc-2 showed a selective localization in tumor and slow clearance from it. At 4 h, the tumor-to-muscle ratios (T/M) were 3.79 for 99mTc-1 and 4.58 for 99mTc-2. These results suggested that 99mTc-labeled PnAO complexes 99mTc-1 and 99mTc-2 might serve as novel hypoxia markers. By introducing a second nitrotriazole redox center, the hypoxic accumulation of the marker was slightly enhanced. Full article
(This article belongs to the Section Medicinal Chemistry)
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283 KiB  
Article
Binding of Bezafibrate to Human Serum Albumin: Insight into the Non-Covalent Interaction of an Emerging Contaminant with Biomacromolecules
by Yajie Qian, Xuefei Zhou, Jiabin Chen and Yalei Zhang
Molecules 2012, 17(6), 6821-6831; https://doi.org/10.3390/molecules17066821 - 04 Jun 2012
Cited by 25 | Viewed by 4681
Abstract
In recent years, bezafibrate (BZF) has been frequently detected in environmental media. In order to reveal the toxicity of such an emerging pollutant, its interaction with human serum albumin (HSA) was studied by fluorescence spectrometry, circular dichroism, and equilibrium dialysis. Fluorescence data showed [...] Read more.
In recent years, bezafibrate (BZF) has been frequently detected in environmental media. In order to reveal the toxicity of such an emerging pollutant, its interaction with human serum albumin (HSA) was studied by fluorescence spectrometry, circular dichroism, and equilibrium dialysis. Fluorescence data showed that the fluorescence quenching of HSA by BZF resulted from the formation of HSA-BZF complex. The binding constants were determined to be 3.33 × 103, 2.84 × 103 M−1 at 298 and 309.5 K, respectively. The thermodynamic determination indicated that the hydrophobic and electrostatic interaction were the dominant binding force. The conformational investigation showed that the presence of BZF increased the α-helix content of HSA and induced the slight unfolding of the polypeptides of protein. Finally, the equilibrium dialysis showed that 0.56 mM BZF decreased the binding of vitamin B2 to HSA by 29%. Full article
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204 KiB  
Article
Strong Inhibition of Celastrol Towards UDP-Glucuronosyl Transferase (UGT) 1A6 and 2B7 Indicating Potential Risk of UGT-Based Herb-Drug Interaction
by Yong-Sheng Zhang, Yan-Yang Tu, Xing-Chun Gao, Jun Yuan, Gang Li, Liang Wang, Jian-Ping Deng, Qi Wang and Ru-Meng Ma
Molecules 2012, 17(6), 6832-6839; https://doi.org/10.3390/molecules17066832 - 05 Jun 2012
Cited by 33 | Viewed by 5535
Abstract
Celastrol, a quinone methide triterpene isolated from Tripterygium wilfordii Hook F., has various biochemical and pharmacological activities, and is now being developed as a promising anti-tumor agent. Inhibitory activity of compounds towards UDP-glucuronosyltransferase (UGT) is an important cause of clinical drug-drug interactions and [...] Read more.
Celastrol, a quinone methide triterpene isolated from Tripterygium wilfordii Hook F., has various biochemical and pharmacological activities, and is now being developed as a promising anti-tumor agent. Inhibitory activity of compounds towards UDP-glucuronosyltransferase (UGT) is an important cause of clinical drug-drug interactions and herb-drug interactions. The aim of the present study is to investigate the inhibition of celastrol towards two important UDP-glucuronosyltransferase (UGT) isoforms UGT1A6 and UGT2B7. Recombinant UGT isoforms and non-specific substrate 4-methylumbelliferone (4-MU) were used. The results showed that celastrol strongly inhibited the UGT1A6 and 2B7-mediated 4-MU glucuronidation reaction, with 0.9 ± 0.1% and 1.8 ± 0.2% residual 4-MU glucuronidation activity at 100 μM of celastrol, respectively. Furthermore, inhibition kinetic study (Dixon plot and Lineweaver-Burk plot) demonstrated that celastrol noncompetitively inhibited the UGT1A1-mediated 4-MU glucuronidation, and competitively inhibited UGT2B7-catalyzed 4-MU glucuronidation. The inhibition kinetic parameters (Ki) were calculated to be 0.49 μM and 0.045 μM for UGT1A6 and UGT2B7, respectively. At the therapeutic concentration of celastrol for anti-tumor utilization, the possibility of celastrol-drug interaction and celastrol-containing herbs-drug interaction were strongly indicated. However, given the complicated nature of herbs, these results should be viewed with more caution. Full article
(This article belongs to the Section Natural Products Chemistry)
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1082 KiB  
Article
Water Assisted Growth of C60 Rods and Tubes by Liquid–Liquid Interfacial Precipitation Method
by Hamid Reza Barzegar, Florian Nitze, Artur Malolepszy, Leszek Stobinski, Cheuk-Wai Tai and Thomas Wågberg
Molecules 2012, 17(6), 6840-6853; https://doi.org/10.3390/molecules17066840 - 05 Jun 2012
Cited by 34 | Viewed by 5121
Abstract
C60 nanorods with hexagonal cross sections are grown using a static liquid–liquid interfacial precipitation method in a system of C60/m-dichlorobenzene solution and ethanol. Adding water to the ethanol phase leads instead to C60 tubes where both length [...] Read more.
C60 nanorods with hexagonal cross sections are grown using a static liquid–liquid interfacial precipitation method in a system of C60/m-dichlorobenzene solution and ethanol. Adding water to the ethanol phase leads instead to C60 tubes where both length and diameter of the C60 tubes can be controlled by the water content in the ethanol. Based on our observations we find that the diameter of the rods/tubes strongly depends on the nucleation step. We propose a liquid-liquid interface growth model of C60 rods and tubes based on the diffusion rate of the good C60 containing solvent into the poor solvent as well as on the size of the crystal seeds formed at the interface between the two solvents. The grown rods and tubes exhibit a hexagonal solvate crystal structure with m-dichlorobenzene solvent molecules incorporated into the crystal structure, independent of the water content. An annealing step at 200 °C at a pressure < 1 kPa transforms the grown structures into a solvent-free face centered cubic structure. Both the hexagonal and the face centered cubic structures are very stable and neither morphology nor structure shows any signs of degradation after three months of storage. Full article
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Article
Pristimerin, a Triterpenoid, Inhibits Tumor Angiogenesis by Targeting VEGFR2 Activation
by Xianmin Mu, Wei Shi, Lixin Sun, Han Li, Zhenzhou Jiang and Luyong Zhang
Molecules 2012, 17(6), 6854-6868; https://doi.org/10.3390/molecules17066854 - 05 Jun 2012
Cited by 46 | Viewed by 6273
Abstract
Pristimerin is a triterpenoid isolated from Celastrus and Maytenus spp. that has been shown to possess a variety of biological activities, including anti-cancer activity. However, little is known about pristimerin’s effects on tumor angiogenesis. In this study, we examined the function and the [...] Read more.
Pristimerin is a triterpenoid isolated from Celastrus and Maytenus spp. that has been shown to possess a variety of biological activities, including anti-cancer activity. However, little is known about pristimerin’s effects on tumor angiogenesis. In this study, we examined the function and the mechanism of this compound in tumor angiogenesis using multiple angiogenesis assays. We found that pristimerin significantly reduced both the volume and weight of solid tumors and decreased angiogenesis in a xenograft mouse tumor model in vivo. Pristimerin significantly inhibited the neovascularization of chicken chorioallantoic membrane (CAM) in vivo and abrogated vascular endothelial growth factor (VEGF)-induced microvessel sprouting in an ex vivo rat aortic ring assay. Furthermore, pristimerin inhibited the VEGF-induced proliferation, migration and capillary-like structure formation of human umbilical vascular endothelial cells (HUVECs) in a concentration-dependent manner. Mechanistic studies revealed that pristimerin suppressed the VEGF-induced phosphorylation of VEGF receptor 2 kinase (KDR/Flk-1) and the activity of AKT, ERK1/2, mTOR, and ribosomal protein S6 kinase. Taken together, our results provide evidence for the first time that pristimerin potently suppresses angiogenesis by targeting VEGFR2 activation. These results provide a novel mechanism of action for pristimerin which may be important in the treatment of cancer. Full article
(This article belongs to the Section Natural Products Chemistry)
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3889 KiB  
Article
Functional and Preliminary Characterisation of Hydrocolloid from Tamarillo (Solanum betaceum Cav.) Puree
by Sri Puvanesvari Gannasin, Yogeshini Ramakrishnan, Noranizan Mohd. Adzahan and Kharidah Muhammad
Molecules 2012, 17(6), 6869-6885; https://doi.org/10.3390/molecules17066869 - 05 Jun 2012
Cited by 49 | Viewed by 6351
Abstract
Hydrocolloid from tamarillo (Solanum betaceum Cav.) puree was extracted using water and characterised for the first time. Proximate compositions of the extracted hydrocolloid were also determined. Functional characteristics such as water-holding capacity, oil-holding capacity, emulsifying activity, emulsion stability, foaming capacity and stability [...] Read more.
Hydrocolloid from tamarillo (Solanum betaceum Cav.) puree was extracted using water and characterised for the first time. Proximate compositions of the extracted hydrocolloid were also determined. Functional characteristics such as water-holding capacity, oil-holding capacity, emulsifying activity, emulsion stability, foaming capacity and stability of the hydrocolloid were evaluated in comparison to that of commercial hydrocolloids. Its functional groups and degree of esterification were determined using Fourier Transform Infrared (FT-IR) spectroscopy. Monosaccharide profiling was done using reverse-phase high pressure liquid chromatography (RP-HPLC). Screening of various fruits for high hydrocolloid yield after water extraction resulted in tamarillo giving the highest yield. The yield on dry weight basis was 8.30%. The hydrocolloid constituted of 0.83% starch, 21.18% protein and 66.48% dietary fibre with 49.47% degree of esterification and the monosaccharides identified were mannose, ribose, rhamnose, galacturonic acid, glucose, galactose, xylose and arabinose. Higher oil-holding capacity, emulsifying activity and emulsion stability compared to commercial hydrocolloids propose its possible application as a food emulsifier and bile acid binder. Foaming capacity of 32.19% and good foam stabilisation (79.36% of initial foam volume after 2 h of foam formation) suggest its promising application in frothy beverages and other foam based food products. These findings suggest that water-extracted tamarillo hydrocolloid can be utilised as an alternative to low methoxyl pectin. Full article
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443 KiB  
Article
Dot Immunobinding Assay Method with Chlorophyll Removal for the Detection of Southern Rice Black-Streaked Dwarf Virus
by Zhuo Chen, Jiaju Liu, Mengjiao Zeng, Zhenchao Wang, Dandan Yu, Chengjun Yin, Linhong Jin, Song Yang and Baoan Song
Molecules 2012, 17(6), 6886-6900; https://doi.org/10.3390/molecules17066886 - 05 Jun 2012
Cited by 30 | Viewed by 6201
Abstract
Southern rice black-streaked dwarf virus (SRBSDV), a new virus from Fiji, has seriously damaged rice crops in southern China and northern Vietnam in recent years. This virus is difficult to diagnose in the early stages of infection, and is very destructive at the [...] Read more.
Southern rice black-streaked dwarf virus (SRBSDV), a new virus from Fiji, has seriously damaged rice crops in southern China and northern Vietnam in recent years. This virus is difficult to diagnose in the early stages of infection, and is very destructive at the late stage. In the present study, a dot immunobinding assay (DIBA) that has a high sensitivity for diagnosing SRBSDV was developed. Two kinds of treatment for the DIBA were evaluated to determine the most effective one for removing chlorophyll interferences via rice extraction. The first included several reagents to remove chlorophyll, namely, the alkaline reagents like magnesium oxide and alumina oxide, the adsorbent reagents like activated carbon and bentonite, as well as the extraction agent acetone. The second and third treatments, which were used to remove chlorophyll in blot membrane-nitrocellulose and polyvinylidene fluoride (PVDF), included several organic solvents containing methanol, ethanol, acetone, ethyl acetate, and diethyl ether. The results showed that activated carbon and methanol yielded the best contrasting purple color for the infected samples by decreasing the chlorophyll content. Full article
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342 KiB  
Article
Catalytic Asymmetric Hydrogenation of 3-Substituted Benzisoxazoles
by Ryuhei Ikeda and Ryoichi Kuwano
Molecules 2012, 17(6), 6901-6915; https://doi.org/10.3390/molecules17066901 - 06 Jun 2012
Cited by 14 | Viewed by 5501
Abstract
A variety of 3-substituted benzisoxazoles were reduced with hydrogen using the chiral ruthenium catalyst, {RuCl(p-cymene)[(R,R)-(S,S)-PhTRAP]}Cl. The ruthenium-catalyzed hydrogenation proceeded in high yield in the presence of an acylating agent, affording a-substituted o [...] Read more.
A variety of 3-substituted benzisoxazoles were reduced with hydrogen using the chiral ruthenium catalyst, {RuCl(p-cymene)[(R,R)-(S,S)-PhTRAP]}Cl. The ruthenium-catalyzed hydrogenation proceeded in high yield in the presence of an acylating agent, affording a-substituted o-hydroxybenzylamines with up to 57% ee. In the catalytic transformation, the N–O bond of the benzisoxazole substrate is reductively cleaved by the ruthenium complex under the hydrogenation conditions. The C–N double bond of the resulting imine is saturated stereoselectively through the PhTRAP–ruthenium catalysis. The hydrogenation produces chiral primary amines, which may work as catalytic poisons, however, the amino group of the hydrogenation product is rapidly acylated when the reaction is conducted in the presence of an appropriate acylating agent, such as Boc2O or Cbz-OSu. Full article
(This article belongs to the Special Issue Asymmetric Catalysis)
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373 KiB  
Article
Potent Anti-HIV Activities and Mechanisms of Action of a Pine Cone Extract from Pinus yunnanensis
by Xuan Zhang, Liu-Meng Yang, Guang-Ming Liu, Ya-Juan Liu, Chang-Bo Zheng, Yong-Jun Lv, Hao-Zhi Li and Yong-Tang Zheng
Molecules 2012, 17(6), 6916-6929; https://doi.org/10.3390/molecules17066916 - 06 Jun 2012
Cited by 20 | Viewed by 6505
Abstract
The anti-HIV activities of a pine cone extract (YNS-PY-F) from Pinus yunnanensis have been evaluated, and its mechanisms of action were also explored. The pine cone extract, YNS-PY-F, potently inhibited HIV-1IIIB, HIV-1RF, HIV-1A17, HIV-1AO18 and [...] Read more.
The anti-HIV activities of a pine cone extract (YNS-PY-F) from Pinus yunnanensis have been evaluated, and its mechanisms of action were also explored. The pine cone extract, YNS-PY-F, potently inhibited HIV-1IIIB, HIV-1RF, HIV-1A17, HIV-1AO18 and HIV-2ROD and induced cytopathic effect in C8166 cells with EC50 values of 0.96 μg/mL, 1.53 μg/mL, 0.88 μg/mL, 7.20 μg/mL and 6.17 μg/mL, respectively. The quantification of a p24 production assay showed that YNS-PY-F significantly inhibited the acute replication of HIV-1IIIB, HIV-1RF, HIV-1A17 and HIV-1AO18 in C8166 cells. An MTT assay showed that YNS-PY-F also significantly inhibited the HIV-1IIIB induced cytolysis in MT-4 cells with an EC50 value of 2.22 μg/mL. The mechanism assays showed that YNS-PY-F had potent inhibitory effects on the fusion between infected cells and uninfected cells, and the activity of HIV-1 reverse transcriptase, with EC50 values of 7.60 μg/mL and 4.60 μg/mL, respectively. Overall, these data suggest that the pine cone extract from Pinus yunnanensis has potent inhibitory activities against HIV-1IIIB, HIV-1RF, RT inhibitor-resistant strains HIV-1A17 and HIV-1AO18, and HIV-2ROD, and its anti-HIV mechanisms include inhibition of HIV entry and inhibition of reverse transcriptase activity. Full article
(This article belongs to the Section Natural Products Chemistry)
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257 KiB  
Article
Bromination and Diazo-Coupling of Pyridinethiones; Microwave Assisted Synthesis of Isothiazolopyridine, Pyridothiazine and Pyridothiazepines
by Ayman M. S. Youssef, Mohamed E. Azab and Mohamed M. Youssef
Molecules 2012, 17(6), 6930-6943; https://doi.org/10.3390/molecules17066930 - 06 Jun 2012
Cited by 16 | Viewed by 5659
Abstract
Isothiazolopyridines, pyridothiazines and pyridothiazepines are important compounds that possess valuable biological activities. This paper reports on the synthesis of these compounds using both conventional chemical methods and modern microwave techniques. 3-Bromo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide, 5-arylazo-6-hydroxy-4-methyl-2-thioxo-1,2-dihydropyridine-3-carboxamides, 3,5-bis-arylazo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-caboxamide, 4-methyl-2,3,6,7-tetra-hydroisothiazolo[5,4-b]-pyridine-3,6-dione, 2,2'-(methylene-bis-(sulfanediyl))bis(4-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide), 2-hydroxy-5-methyl-4H-pyrido[3,2-e][1,3]-thiazine-4,7(8H)-dione and 2-arylmethylene-8-hydroxy-6-methyl-2,3,4,5-tetrahydropyrido-[3,2-f][1,4]thiazepine-3,5-diones have [...] Read more.
Isothiazolopyridines, pyridothiazines and pyridothiazepines are important compounds that possess valuable biological activities. This paper reports on the synthesis of these compounds using both conventional chemical methods and modern microwave techniques. 3-Bromo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide, 5-arylazo-6-hydroxy-4-methyl-2-thioxo-1,2-dihydropyridine-3-carboxamides, 3,5-bis-arylazo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-caboxamide, 4-methyl-2,3,6,7-tetra-hydroisothiazolo[5,4-b]-pyridine-3,6-dione, 2,2'-(methylene-bis-(sulfanediyl))bis(4-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide), 2-hydroxy-5-methyl-4H-pyrido[3,2-e][1,3]-thiazine-4,7(8H)-dione and 2-arylmethylene-8-hydroxy-6-methyl-2,3,4,5-tetrahydropyrido-[3,2-f][1,4]thiazepine-3,5-diones have been prepared from 6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide. Some of these compounds were prepared using microwave-assisted reaction conditions, that provided higher yields in shorter times than the conventional methods. Full article
(This article belongs to the Section Organic Chemistry)
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247 KiB  
Article
Two New Coumarins from Micromelum falcatum with Cytotoxicity and Brine Shrimp Larvae Toxicity
by Xiongming Luo, Weihong He, Hao Yin, Qingxin Li, Qiao Liu, Yongzhong Huang and Si Zhang
Molecules 2012, 17(6), 6944-6952; https://doi.org/10.3390/molecules17066944 - 06 Jun 2012
Cited by 13 | Viewed by 5481
Abstract
Two new coumarins, 7-methoxy-8-(2-hydroxmethyl-1-O-isovaleryl-4-butenyl)-coumarin (1) and 7-methoxy-8-(1-hydroxy-2-O-b-glucopyranosyl-3-methyl-4-butene-1-yl)coumarin (2), and twelve known coumarins 3–14 were isolated from the stem bark of Micromelum falcatum. The structures of compounds 1–14 were elucidated by extensive spectroscopic data analyses. The toxicity of [...] Read more.
Two new coumarins, 7-methoxy-8-(2-hydroxmethyl-1-O-isovaleryl-4-butenyl)-coumarin (1) and 7-methoxy-8-(1-hydroxy-2-O-b-glucopyranosyl-3-methyl-4-butene-1-yl)coumarin (2), and twelve known coumarins 3–14 were isolated from the stem bark of Micromelum falcatum. The structures of compounds 1–14 were elucidated by extensive spectroscopic data analyses. The toxicity of compounds 1–14 was tested using a brine shrimp assay and in vitro antiproliferative assay against mammary cancer (F10) and lung cancer (HvEvc) cell lines by the MTT method. Some compounds had moderate activities. All compounds were also tested against the microorganisms Bacillus subtilis, Bacillus thuringiensis and Escherichia coli, but no activity was observed. Full article
(This article belongs to the Special Issue Coumarins and Xanthones)
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370 KiB  
Article
Identification of Volatile Components of Liverwort (Porella cordaeana) Extracts Using GC/MS-SPME and Their Antimicrobial Activity
by Danka Bukvicki, Davide Gottardi, Milan Veljic, Petar D. Marin, Lucia Vannini and Maria Elisabetta Guerzoni
Molecules 2012, 17(6), 6982-6995; https://doi.org/10.3390/molecules17066982 - 06 Jun 2012
Cited by 25 | Viewed by 5928
Abstract
Chemical constituents of liverwort (Porella cordaeana) extracts have been identified using solid-phase microextraction-gas chromatography mass spectrometry (SPME-GC/MS). The methanol, ethanol and ethyl acetate extracts were rich in terpenoids such as sesquiterpene hydrocarbons (53.12%, 51.68%, 23.16%), and monoterpene hydrocarbons (22.83%, 18.90%, 23.36%), [...] Read more.
Chemical constituents of liverwort (Porella cordaeana) extracts have been identified using solid-phase microextraction-gas chromatography mass spectrometry (SPME-GC/MS). The methanol, ethanol and ethyl acetate extracts were rich in terpenoids such as sesquiterpene hydrocarbons (53.12%, 51.68%, 23.16%), and monoterpene hydrocarbons (22.83%, 18.90%, 23.36%), respectively. The dominant compounds in the extracts were β-phellandrene (15.54%, 13.66%, 12.10%) and β-caryophyllene (10.72%, 8.29%, 7.79%, respectively). The antimicrobial activity of the extracts was evaluated against eleven food microorganisms using the microdilution and disc diffusion methods. The minimum inhibitory concentration (MIC) varied from 0.50 to 2.00 mg/mL for yeast strains (Saccharomyces cerevisiae 635, Zygosacharomyces bailii 45, Aerobasidium pullulans L6F, Pichia membranaefaciens OC 71, Pichia membranaefaciens OC 70, Pichia anomala CBS 5759, Pichia anomala DBVPG 3003 and Yarrowia lipolytica RO13), and from 1.00 to 3.00 mg/mL for bacterial strains (Salmonella enteritidis 155, Escherichia coli 555 and Listeria monocytogenes 56Ly). Methanol extract showed better activity in comparison with ethanol and ethyl acetate extracts. High percentages of monoterpene and sesquiterpene hydrocarbons could be responsible for the better antimicrobial activity. Full article
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1603 KiB  
Article
In Vitro, in Situ and in Vivo Studies on the Anticandidal Activity of Cassia fistula Seed Extract
by Subramanion L. Jothy, Zuraini Zakariah, Yeng Chen and Sreenivasan Sasidharan
Molecules 2012, 17(6), 6997-7009; https://doi.org/10.3390/molecules17066997 - 07 Jun 2012
Cited by 19 | Viewed by 5521
Abstract
Cassia fistula seeds have many therapeutic uses in traditional medicine practice. The present investigation was undertaken to demonstrate the anticandidal activity of the C. fistula seed extract at ultra-structural level through transmission electron microscope (TEM) and scanning electron microscope (SEM) observations. The effect [...] Read more.
Cassia fistula seeds have many therapeutic uses in traditional medicine practice. The present investigation was undertaken to demonstrate the anticandidal activity of the C. fistula seed extract at ultra-structural level through transmission electron microscope (TEM) and scanning electron microscope (SEM) observations. The effect of seed extract on the growth profile of the Candida albicans was examined via time-kill assays and in vivo efficacy of the extract was tested in an animal model. In addition, the anticandidal effect of seed extract was further evaluated by microscopic observations using SEM and TEM to determine any major alterations in the ultrastructure of C. albicans. The complete inhibition of C. albicans growth was shown by C. fistula seed extract at 6.25 mg/mL concentration. The time-kill assay suggested that C. fistula seed extract had completely inhibited the growth of C. albicans and also exhibited prolonged anti-yeast activity. The SEM and TEM observations carried out to distinguish the metamorphosis in the morphology of control and C. fistula seed extract-treated C. albicans cells revealed the notable effect on the outer cell wall and cytoplasmic content of the C. albicans and complete collapse of yeast cell exposed to seed extract at concentration 6.25 mg/mL at 36 h. The in vitro time-kill study performed using the leaf extract at 1/2, 1 or 2 times of the MIC significantly inhibited the yeast growth with a noticeable drop in optical density (OD) of yeast culture, thus confirming the fungicidal effect of the extract on C. albicans. In addition, in vivo antifungal activity studies on candidiasis in mice showed a 6-fold decrease in C. albicans in kidneys and blood samples in the groups of animals treated with the extract (2.5 g/kg body weight). The results suggested that the C. fistula seed extract possessed good anticandidal activity and is a potential candidate for the development of anticandidal agents. Full article
(This article belongs to the Section Natural Products Chemistry)
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633 KiB  
Article
5-(5-Aryl-1,3,4-oxadiazole-2-carbonyl)furan-3-carboxylate and New Cyclic C-Glycoside Analogues from Carbohydrate Precursors with MAO-B, Antimicrobial and Antifungal Activities
by Mohamed Mohamed El-Sadek, Seham Yassen Hassan, Nagwa Said Abd El-Dayem and Galila Ahmed Yacout
Molecules 2012, 17(6), 7010-7027; https://doi.org/10.3390/molecules17067010 - 07 Jun 2012
Cited by 16 | Viewed by 4884
Abstract
Cyclization of acyclic C-glycoside derivatives 1a,b to 2a,b as the major isomers, and 4a,b as the minor isomers were carried out. The isopropylidene derivatives 3a,b were prepared, as well as the hydrazide derivative 6, which was condensed with a variety of [...] Read more.
Cyclization of acyclic C-glycoside derivatives 1a,b to 2a,b as the major isomers, and 4a,b as the minor isomers were carried out. The isopropylidene derivatives 3a,b were prepared, as well as the hydrazide derivative 6, which was condensed with a variety of aldehydes to give hydrazones 7a–e which were also prepared from the compounds 12a–e. Acetylation of 7a,d gave the corresponding acetyl derivatives 8a,d, respectively. In addition, the dicarbonyl compound 9 was prepared in the hydrate form, which reacted with a number of aroylhydrazines to give the corresponding bisaroyl-hydrazones 10a–d, which were cyclized into 1,3,4-oxadiazoles 11a–d. Furthermore, two of the prepared compounds were examined to show the ability to activate MAO-B. In addition a number of prepared compounds showed antibacterial and antiviral activities. Full article
(This article belongs to the Special Issue Heterocycles)
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Article
Action of Chitosan Against Xanthomonas Pathogenic Bacteria Isolated from Euphorbia pulcherrima
by Yanli Wang, Liping Li, Bin Li, Guoxing Wu, Qiaomei Tang, Muhammad Ibrahim, Hongye Li, Guanlin Xie and Guochang Sun
Molecules 2012, 17(6), 7028-7041; https://doi.org/10.3390/molecules17067028 - 07 Jun 2012
Cited by 31 | Viewed by 6200
Abstract
The antibacterial activity and mechanism of two kinds of chitosan were investigated against twelve Xanthomonas strains recovered from Euphorbia pulcherrima. Results indicated that both chitosans markedly inhibited bacterial growth based on OD loss. Furthermore, the release of DNA and RNA from three [...] Read more.
The antibacterial activity and mechanism of two kinds of chitosan were investigated against twelve Xanthomonas strains recovered from Euphorbia pulcherrima. Results indicated that both chitosans markedly inhibited bacterial growth based on OD loss. Furthermore, the release of DNA and RNA from three selected strains was increased by both chitosans. However, the release of intracellular proteins was inhibited by both chitosans at different concentration and incubation times, except chitosan A at 0.1 mg/mL for 0.5 h incubation and 0.2 mg/mL for 2.0 h incubation increased the release of proteins, indicating the complexity of the interaction and cell membranes, which was affected by incubation time, bacterial species, chitosan type and concentration. Transmission electron microscopic observations revealed that chitosan caused changes in protoplast concentration and surface morphology. In some cells, the membranes and walls were badly distorted and disrupted, while other cells were enveloped by a thick and compact ribbon-like layer. The contrary influence on cell morphology may explain the differential effect in the release of material. In addition, scanning electron microscope and biofilm formation test revealed that both chitosans removed biofilm biomass. Overall, this study showed that membrane and biofilm play an important role in the antibacterial mechanism of chitosan. Full article
(This article belongs to the Section Medicinal Chemistry)
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Article
Synthesis and in Vitro Cytotoxic Evaluation of Aminoquinones Structurally Related to Marine Isoquinolinequinones
by Virginia Delgado, Andrea Ibacache, Cristina Theoduloz and Jaime A. Valderrama
Molecules 2012, 17(6), 7042-7056; https://doi.org/10.3390/molecules17067042 - 07 Jun 2012
Cited by 27 | Viewed by 5107
Abstract
The synthesis of 4-methoxycarbonyl-3-methylisoquinolinequinone (1) and a variety of its substitution products with amino-, alkylamino and halogen groups on the quinone nucleus is reported. The series of 6-, 7- and 6,7-subtituted isoquinolinequinones were evaluated in vitro for their cytotoxic activity using [...] Read more.
The synthesis of 4-methoxycarbonyl-3-methylisoquinolinequinone (1) and a variety of its substitution products with amino-, alkylamino and halogen groups on the quinone nucleus is reported. The series of 6-, 7- and 6,7-subtituted isoquinolinequinones were evaluated in vitro for their cytotoxic activity using the MTT colorimetric method. All the newly synthesized compounds showed moderate to high potency against MRC-5 healthy lung fibroblasts and four human tumor cell lines: AGS gastric adenocarcinoma, SK-MES-1 lung, J82 bladder carcinoma, and HL-60 leukemia cells. Among the series, compounds 4b, 12 and 13 exhibited interesting antitumor activity against human gastric adenocarcinoma, human lung and human bladder carcinoma cancer cells. 7-Amino-6-bromoisoquinoline-5,8-quinone (13) was found to be the most promising active compound against the tested cancer cell lines, with IC50 values in the 0.21−0.49 mM range, lower than the anti-cancer agent etoposide used as reference. Full article
(This article belongs to the Section Organic Chemistry)
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Article
Chemical Composition of Essential Oils of Litsea cubeba Harvested from Its Distribution Areas in China
by Linlin Si, Yicun Chen, Xiaojiao Han, Zhiyong Zhan, Shengping Tian, Qinqin Cui and Yangdong Wang
Molecules 2012, 17(6), 7057-7066; https://doi.org/10.3390/molecules17067057 - 08 Jun 2012
Cited by 97 | Viewed by 9074
Abstract
Litsea cubeba (Lour.) Pers. is a promising industrial crop with fruits rich in essential oils. The chemical composition of essential oils of L. cubeba (EOLC) were determined for fruits harvested from eight regions in China. The overall essential oil content, obtained by hydrodistillation [...] Read more.
Litsea cubeba (Lour.) Pers. is a promising industrial crop with fruits rich in essential oils. The chemical composition of essential oils of L. cubeba (EOLC) were determined for fruits harvested from eight regions in China. The overall essential oil content, obtained by hydrodistillation and analyzed by gas chromatography–mass spectrometry (GC-MS), ranged from 3.04% to 4.56%. In total, 59 compounds were identified, the dominant components being monoterpenes (94.4–98.4%), represented mainly by neral and geranial (78.7–87.4%). D-Limonene was unexpectedly a lesser constituent (0.7–5.3%) in fruits, which differed from previous reports (6.0–14.6%). Several components were only detected in certain regions and compounds such as o-cymene and eremophilene have never before been reported in EOLC. These results demonstrate significant regional variation in the chemical composition of EOLC. This investigation provides important information with regard to the bioactivity, breeding work and industrial applications of L. cubeba. Full article
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Article
Synthesis, DNA-Binding and Antiproliferative Properties of Acridine and 5-Methylacridine Derivatives
by Rubén Ferreira, Anna Aviñó, Stefania Mazzini and Ramon Eritja
Molecules 2012, 17(6), 7067-7082; https://doi.org/10.3390/molecules17067067 - 08 Jun 2012
Cited by 25 | Viewed by 6491
Abstract
Several acridine derivatives were synthesized and their anti-proliferative activity was determined. The most active molecules were derivatives of 5-methylacridine-4-carboxylic acid. The DNA binding properties of the synthesized acridines were analyzed by competitive dialysis and compared with the anti-proliferative activities. While inactive acridine derivatives [...] Read more.
Several acridine derivatives were synthesized and their anti-proliferative activity was determined. The most active molecules were derivatives of 5-methylacridine-4-carboxylic acid. The DNA binding properties of the synthesized acridines were analyzed by competitive dialysis and compared with the anti-proliferative activities. While inactive acridine derivatives showed high selectivity for G-quadruplex structures, the most active 5-methylacridine-4-carboxamide derivatives had high affinity for DNA but showed poor specificity. An NMR titration study was performed with the most active 5-methylacridine-4-carboxamide, confirming the high affinity of this compound for both duplex and quadruplex DNAs. Full article
(This article belongs to the Special Issue Nucleic Acid Analogs)
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Article
Astragalus Polysaccharide Improves Palmitate-Induced Insulin Resistance by Inhibiting PTP1B and NF-κB in C2C12 Myotubes
by Ming Zhao, Zhao-Feng Zhang, Ye Ding, Jun-Bo Wang and Yong Li
Molecules 2012, 17(6), 7083-7092; https://doi.org/10.3390/molecules17067083 - 11 Jun 2012
Cited by 48 | Viewed by 8416
Abstract
We investigated the effects of Astragalus polysaccharide (APS) on palmitate-induced insulin resistance in C2C12 skeletal muscle myotubes. Palmitate-reduced glucose uptake was restored by APS. APS prevented palmitate-induced C2C12 myotubes from impaired insulin signaling by inhibiting Ser307 phosphorylation of insulin receptor substrate-1 (IRS-1) and [...] Read more.
We investigated the effects of Astragalus polysaccharide (APS) on palmitate-induced insulin resistance in C2C12 skeletal muscle myotubes. Palmitate-reduced glucose uptake was restored by APS. APS prevented palmitate-induced C2C12 myotubes from impaired insulin signaling by inhibiting Ser307 phosphorylation of insulin receptor substrate-1 (IRS-1) and increasing Ser473 phosphorylation of Akt. Moreover, the increases in protein-tyrosine phosphatase-1B (PTP1B) protein level and NF-κB activation associated with palmitate treatment were also prevented by APS. However the treatment with APS didn’t change AMP-activated protein kinase (AMPK) activation in palmitate-induced myotubes. The results of the present study suggest that Astragalus polysaccharide inhibits palmitate-induced insulin resistance in C2C12 myotubes by inhibiting expression of PTP1B and regulating NF-κB but not AMPK pathway. Full article
(This article belongs to the Section Natural Products Chemistry)
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Article
Lycopene Effects on Serum Mineral Elements and Bone Strength in Rats
by Haidong Liang, Fang Yu, Zhihong Tong and Weifeng Zeng
Molecules 2012, 17(6), 7093-7102; https://doi.org/10.3390/molecules17067093 - 11 Jun 2012
Cited by 22 | Viewed by 4739
Abstract
This study investigated the beneficial effect of lycopene on bone biomarkers in ovariectomized (OVX) rats. Female Wistar rats were either sham operated or surgically ovariectomized and then fed with lycopene for 8 weeks. Serum Ca, P, alkaline phosphatase (ALP), interleukin 6 (IL-6) [...] Read more.
This study investigated the beneficial effect of lycopene on bone biomarkers in ovariectomized (OVX) rats. Female Wistar rats were either sham operated or surgically ovariectomized and then fed with lycopene for 8 weeks. Serum Ca, P, alkaline phosphatase (ALP), interleukin 6 (IL-6) and bone gla protein (BGP) concentration was significantly higher in the untreated OVX group compared with that of the sham group, whereas serum estrogen levels were lower. Bone mineral density (BMD), BMD/wt, bone mineral content (BMC), BMC/wt values, maximum load, stiffness, energy and maximum stress were significantly lower in the untreated OVX group compared with that of the sham group. Administration of lycopene (20, 30 and 40 mg/kg b.w.) for 8 weeks significantly decreased serum Ca, P, ALP, and IL-6 concentration, and enhanced serum estrogen level, BMD, BMD/wt, BMC, BMC/wt values, maximum load, stiffness, energy and maximum stress in lycopene-treated OVX groups. In conclusion, the consumption of lycopene may have the most protective effect on bone in OVX rats. Full article
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Article
The Potential Biotechnological Applications of the Exopolysaccharide Produced by the Halophilic Bacterium Halomonas almeriensis
by Inmaculada Llamas, Hakima Amjres, Juan Antonio Mata, Emilia Quesada and Victoria Béjar
Molecules 2012, 17(6), 7103-7120; https://doi.org/10.3390/molecules17067103 - 12 Jun 2012
Cited by 96 | Viewed by 7291
Abstract
We have studied the extracellular polysaccharide (EPS) produced by the type strain, M8T, of the halophilic bacterium Halomonas almeriensis, to ascertain whether it might have any biotechnological applications. All the cultural parameters tested influenced both bacterial growth and polysaccharide production. [...] Read more.
We have studied the extracellular polysaccharide (EPS) produced by the type strain, M8T, of the halophilic bacterium Halomonas almeriensis, to ascertain whether it might have any biotechnological applications. All the cultural parameters tested influenced both bacterial growth and polysaccharide production. EPS production was mainly growth-associated and under optimum environmental and nutritional conditions M8T excreted about 1.7 g of EPS per litre of culture medium (about 0.4 g of EPS per gram of dry cell weight). Analysis by anion-exchange chromatography and high-performance size-exclusion chromatography indicated that the exopolysaccharide was composed of two fractions, one of 6.3 × 106 and another of 1.5 × 104 Daltons. The monosaccharide composition of the high-molecular-weight fraction was mannose (72% w/w), glucose (27.5% w/w) and rhamnose (0.5% w/w). The low-molecular-weight fraction contained mannose (70% w/w) and glucose (30% w/w). The EPS has a substantial protein fraction (1.1% w/w) and was capable of emulsifying several hydrophobic substrates, a capacity presumably related to its protein content. The EPS produced solutions of low viscosity with pseudoplastic behaviour. It also had a high capacity for binding some cations. It contained considerable quantities of sulphates (1.4% w/w), an unusual feature in bacterial polysaccharides. All these characteristics render it potentially useful as a biological agent, bio-detoxifier and emulsifier. Full article
(This article belongs to the Special Issue Natural Polysaccharides: Chemistry, Bioactivity and Analysis)
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544 KiB  
Article
Cooperative Al(Salen)-Pyridinium Catalysts for the Asymmetric Synthesis of trans-Configured β-Lactones by [2+2]-Cyclocondensation of Acylbromides and Aldehydes: Investigation of Pyridinium Substituent Effects
by Patrick Meier, Florian Broghammer, Katja Latendorf, Guntram Rauhut and René Peters
Molecules 2012, 17(6), 7121-7150; https://doi.org/10.3390/molecules17067121 - 12 Jun 2012
Cited by 48 | Viewed by 7139
Abstract
The trans-selective catalytic asymmetric formation of β-lactones constitutes an attractive surrogate for anti-aldol additions. Recently, we have reported the first catalyst which is capable of forming trans-β-lactones with high enantioselectivity from aliphatic (and aromatic) aldehyde substrates by cyclocondensation with acyl [...] Read more.
The trans-selective catalytic asymmetric formation of β-lactones constitutes an attractive surrogate for anti-aldol additions. Recently, we have reported the first catalyst which is capable of forming trans-β-lactones with high enantioselectivity from aliphatic (and aromatic) aldehyde substrates by cyclocondensation with acyl bromides. In that previous study the concepts of Lewis acid and organic aprotic ion pair catalysis were combined in a salen-type catalyst molecule. Since a pyridinium residue on the salen periphery is essential for high trans- and enantioselectivity, we were interested in the question of whether substituents on the pyridinium rings could be used to further improve the catalyst efficiency, as they might have a significant impact on the effective charges within the heterocycles. In the present study we have thus compared a small library of aluminum salen/bispyridinium catalysts mainly differing in the substituents on the pyridinium residues. As one result of these studies a new catalyst was identified which offers slightly superior stereoselectivity as compared to the previously reported best catalyst. NBO calculations have revealed that the higher stereoselectivity can arguably not be explained by the variation of the effective charge. Full article
(This article belongs to the Special Issue Asymmetric Catalysis)
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Article
Effect of Frozen Storage on Molecular Weight, Size Distribution and Conformation of Gluten by SAXS and SEC-MALLS
by Lei Zhao, Lin Li, Guo-Qin Liu, Xing-Xun Liu and Bing Li
Molecules 2012, 17(6), 7169-7182; https://doi.org/10.3390/molecules17067169 - 12 Jun 2012
Cited by 59 | Viewed by 5351
Abstract
In this study, the effects of frozen (−18 °C) storage time on molecular weight, size distribution, conformation, free amino groups and free sulfhydryl groups of gluten were studied by small-angle X-ray scattering (SAXS), multi-angle laser light scattering (MALLS) in conjunction with a size [...] Read more.
In this study, the effects of frozen (−18 °C) storage time on molecular weight, size distribution, conformation, free amino groups and free sulfhydryl groups of gluten were studied by small-angle X-ray scattering (SAXS), multi-angle laser light scattering (MALLS) in conjunction with a size exclusion chromatography (SEC) and spectrophotometrically. The results showed that the gluten dissolved in 50 mM acetic acid appeared to be similar to quasi-spherical of the chain conformation and the slope of the conformation plot decreased during the storage. Both the molecular weight and radius of gyration of the frozen gluten decreased with the storage time showing a depolymerization in the high molecular weight fraction of gluten (105 Da ~ 109 Da). Therefore, at constant molecular weight the change of the chain conformation did not show a clear correlation with the storage time. The free amino groups content changed little and the free sulfhydryl groups content of the gluten increased from 9.8 μmol/g for the control to 12.87 μmol/g for 120-day-stored gluten, indicating that the water redistribution and ice recrystallization lead to the breakage of the disulphide bonds and may be one of the reasons for the depolymerization of gluten polymer. Full article
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294 KiB  
Article
Comparison of the Chemical Composition and Pharmacological Effects of the Aqueous and Ethanolic Extracts from a Tibetan “Snow Lotus” (Saussurea laniceps) Herb
by Tao Yi, Hongwing Lo, Zhongzhen Zhao, Zhiling Yu, Zhijun Yang and Hubiao Chen
Molecules 2012, 17(6), 7183-7194; https://doi.org/10.3390/molecules17067183 - 12 Jun 2012
Cited by 34 | Viewed by 5381
Abstract
To understand the impacts of different processing methods on the composition and effects of the herb Saussurea laniceps (SL), the present study report the first comparison of the chemical constituents of aqueous and ethanolic SL extracts using chromatographic analysis, and to compare their [...] Read more.
To understand the impacts of different processing methods on the composition and effects of the herb Saussurea laniceps (SL), the present study report the first comparison of the chemical constituents of aqueous and ethanolic SL extracts using chromatographic analysis, and to compare their pharmacological effects in a mouse anti-inflammatory, anti-nociceptive model and an in vitro anti-oxidant test. Chemical comparison demonstrated that the types of chemicals in the two extracts were identical, but the contents of the main constituents in the aqueous extract were lower than those of the ethanolic extract. A transesterification of dicaffeoylquinic acids took place in the aqueous extract during boiling. As for pharmacological effects, oral administration of aqueous and ethanolic SL extracts significantly inhibited croton oil-induced mice ear edema, and significantly inhibited acetic acid-induced mice writhings, respectively. In the DPPH anti-oxidant activity test, the IC50 values were calculated as 409.6 mg/L and 523.4 mg/L for the ethanolic and aqueous extracts, respectively. The inhibitory effects of the ethanolic extract were more potent than those of the aqueous extract in all pharmacological tests, although there was no significant difference. This study suggests that the two preparations should be distinguished when used. Full article
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Article
Ginsenoside Rb1 Attenuates Intestinal Ischemia Reperfusion Induced Renal Injury by Activating Nrf2/ARE Pathway
by Qian Sun, Qing-Tao Meng, Ying Jiang and Zhong-Yuan Xia
Molecules 2012, 17(6), 7195-7205; https://doi.org/10.3390/molecules17067195 - 12 Jun 2012
Cited by 51 | Viewed by 7086
Abstract
Intestinal ischemia reperfusion (IIR) is a serious clinical condition associated with simultaneous multiple organ dysfunction. The aim of this study was to investigate the effects of ginsenoside Rb1 on IIR induced renal injury in mice. An intestinal ischemia reperfusion mouse model was established [...] Read more.
Intestinal ischemia reperfusion (IIR) is a serious clinical condition associated with simultaneous multiple organ dysfunction. The aim of this study was to investigate the effects of ginsenoside Rb1 on IIR induced renal injury in mice. An intestinal ischemia reperfusion mouse model was established by superior mesenteric artery (SMA) occlusion for 45 min, followed by reperfusion for 2 h. IIR induced renal injury characterized by increase of BUN, Cr and NGAL in serum, MDA levels and decrease of SOD levels in the renal tissues. Ginsenoside Rb1 (30, 60 mg/kg) given intraperitoneally before reperfusion attennuated renal injury, which was associated with decrease of BUN, Cr and NGAL in serum, MDA levels and increase of SOD levels in the renal tissues. Furthermore, the immunohistochemistry and Western blot data showed that ginsenoside Rb1 dramatically reversed IIR induced renal injury, associated with upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in renal tissues. Our data suggests that ginsenoside Rb1 attenuates acute renal injury induced by intestinal ischemia reperfusion by activating the Nrf2/ARE pathway. Full article
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Article
Liquiritigenin Inhibits Tumor Growth and Vascularization in a Mouse Model of Hela Cells
by Yuxin Liu, Sirou Xie, Yu Wang, Kang Luo, Yang Wang and Yunqing Cai
Molecules 2012, 17(6), 7206-7216; https://doi.org/10.3390/molecules17067206 - 12 Jun 2012
Cited by 44 | Viewed by 6920
Abstract
Angiogenesis is one of the crucial steps in the transition of a tumor from a small, harmless cluster of mutated cells to a large, malignant growth, capable of spreading to other organs throughout the body. Vascular endothelial growth factor (VEGF) that stimulates vasculogenesis [...] Read more.
Angiogenesis is one of the crucial steps in the transition of a tumor from a small, harmless cluster of mutated cells to a large, malignant growth, capable of spreading to other organs throughout the body. Vascular endothelial growth factor (VEGF) that stimulates vasculogenesis and angiogenesis is thought to be as an anti-angiogenic target for cancer therapy. Liquiritigenin (LQ), a flavanone existing in Radix glycyrrhiza, shows extensive biological activities, such as anti-inflammatory and anti-cancer properties. In our studies, liquiritigenin effectively inhibited the growth of tumors xenografted in nude mice from human cervical cancer cell line HeLa cells, and microvascular density (MVD) of the tumor exposed to liquiritigenin was reduced in a dose dependent manner, especially in the high dose group. Moreover, the expression and secretion of VEGF were down-regulated by the drug in vivo and in vitro. Therefore, liquiritigenin can be further studied on cancer and other diseases associated with VEGF up-regulation. Full article
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Article
Synthesis and Biological Evaluation of Thiophene Derivatives as Acetylcholinesterase Inhibitors
by Mohamed M. Ismail, Mona M. Kamel, Lamia W. Mohamed, Samar I. Faggal and Mai A. Galal
Molecules 2012, 17(6), 7217-7231; https://doi.org/10.3390/molecules17067217 - 12 Jun 2012
Cited by 29 | Viewed by 5067
Abstract
A series of new thiophene derivatives has been synthesized using the Gewald protocol. The acetylcholinesterase inhibition activity was assayed according to Ellman’s method using donepezil as reference. Some of the compounds were found to be more potent inhibitors than the reference. 2-(2-(4-(4-Methoxyphenyl)piperazin-1-yl)acetamido)-4,5,6,7-tetrahydrobenzo[b [...] Read more.
A series of new thiophene derivatives has been synthesized using the Gewald protocol. The acetylcholinesterase inhibition activity was assayed according to Ellman’s method using donepezil as reference. Some of the compounds were found to be more potent inhibitors than the reference. 2-(2-(4-(4-Methoxyphenyl)piperazin-1-yl)acetamido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (IIId) showed 60% inhibition, compared to only 40% inhibition by donepezil. Full article
(This article belongs to the Section Medicinal Chemistry)
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Article
Astragalus membranaceus Extract Activates Immune Response in Macrophages via Heparanase
by Qiaojing Qin, Jianying Niu, Zhaoxia Wang, Wangjie Xu, Zhongdong Qiao and Yong Gu
Molecules 2012, 17(6), 7232-7240; https://doi.org/10.3390/molecules17067232 - 13 Jun 2012
Cited by 22 | Viewed by 6675
Abstract
Astragalus membranaceus (AM), a traditional Chinese medicinal herb, has immunoregulatory properties in many diseases. We investigated the effects and mechanism of Astragalus membranaceus extract (AME) in the macrophage migration and immune response mediator release. The viability of Ana-1 macrophages treated with AME was [...] Read more.
Astragalus membranaceus (AM), a traditional Chinese medicinal herb, has immunoregulatory properties in many diseases. We investigated the effects and mechanism of Astragalus membranaceus extract (AME) in the macrophage migration and immune response mediator release. The viability of Ana-1 macrophages treated with AME was evaluated by the MTT method. The secretion and mRNA levels of IL-1β and TNF-a were measured by ELISA and RT-PCR, respectively. Macrophage migration was assayed by transwell assay. The activity of heparanase (HPA) was determined by a heparin-degrading enzyme assay. Our results didn’t show any toxicity of AME in macrophages. AME increased the activity of HPA, cell migration, mRNA levels and secretion of IL-1β and TNF-a in macrophages. Pretreatment with anti-HPA antibody reduced cell migration, secretion of IL-1β and TNF-a did not change the mRNA levels of IL-1β and TNF-a significantly in AME-treated macrophages. This suggests that AME may increase the release of immune response mediator and cell migration via HPA to activate immune response in macrophages. Full article
(This article belongs to the Section Natural Products Chemistry)
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510 KiB  
Article
Aqueous Extracts of the Edible Gracilaria tenuistipitata are Protective Against H2O2-Induced DNA Damage, Growth Inhibition, and Cell Cycle Arrest
by Jing-Iong Yang, Chi-Chen Yeh, Jin-Ching Lee, Szu-Cheng Yi, Hurng-Wern Huang, Chao-Neng Tseng and Hsueh-Wei Chang
Molecules 2012, 17(6), 7241-7254; https://doi.org/10.3390/molecules17067241 - 13 Jun 2012
Cited by 57 | Viewed by 7537
Abstract
Potential antioxidant properties of an aqueous extract of the edible red seaweed Gracilaria tenuistipitata (AEGT) against oxidative DNA damage were evaluated. The AEGT revealed several antioxidant molecules, including phenolics, flavonoids and ascorbic acid. In a cell-free assay, the extract exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical [...] Read more.
Potential antioxidant properties of an aqueous extract of the edible red seaweed Gracilaria tenuistipitata (AEGT) against oxidative DNA damage were evaluated. The AEGT revealed several antioxidant molecules, including phenolics, flavonoids and ascorbic acid. In a cell-free assay, the extract exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity that significantly reduced H2O2-induced plasmid DNA breaks in a dose-response manner (P < 0.001). The AEGT also suppressed H2O2-induced oxidative DNA damage in H1299 cells by reducing the percentage of damaged DNA in a dose-response manner (P < 0.001) as measured by a modified alkaline comet-nuclear extract (comet-NE) assay. The MTT assay results showed that AEGT confers significant protection against H2O2-induced cytotoxicity and that AEGT itself is not cytotoxic (P < 0.001). Moreover, H2O2-induced cell cycle G2/M arrest was significantly released when cells were co-treated with different concentrations of AEGT (P < 0.001). Taken together, these findings suggest that edible red algae Gracilaria water extract can prevent H2O2-induced oxidative DNA damage and its related cellular responses. Full article
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Article
Chemical Composition and Insecticidal Activity Against Sitophilus zeamais of the Essential Oils Derived from Artemisia giraldii and Artemisia subdigitata
by Sha-Sha Chu, Zhi-Long Liu, Shu-Shan Du and Zhi-Wei Deng
Molecules 2012, 17(6), 7255-7265; https://doi.org/10.3390/molecules17067255 - 13 Jun 2012
Cited by 37 | Viewed by 5253
Abstract
The aim of this research was to determine the chemical composition and insecticidal activity of the essential oils derived from flowering aerial parts of Artemisia giraldii Pamp. and A. subdigitata Mattf. (Family: Asteraceae) against the maize weevil (Sitophilus zeamais Motsch.). Essential oils [...] Read more.
The aim of this research was to determine the chemical composition and insecticidal activity of the essential oils derived from flowering aerial parts of Artemisia giraldii Pamp. and A. subdigitata Mattf. (Family: Asteraceae) against the maize weevil (Sitophilus zeamais Motsch.). Essential oils of aerial parts of A. giraldii and A. subdigitata were obtained from hydrodistillation and investigated by GC and GC-MS. A total of 48 and 33 components of the essential oils of A. giraldii and A. subdigitata were identified, respectively. The principal compounds in A. giraldii essential oil were β-pinene (13.18%), iso-elemicin (10.08%), germacrene D (5.68%), 4-terpineol (5.43%) and (Z)-β-ocimene (5.06%). 1,8-Cineole (12.26%) and α-curcumene (10.77%) were the two main components of the essential oil of A. subdigitata, followed by β-pinene (7.38%), borneol (6.23%) and eugenol (5.87%). The essential oils of A. giraldii and A. subdigitata possessed fumigant toxicity against the maize weevils with LC50 values of 6.29 and 17.01 mg/L air, respectively. The two essential oils of A. giraldii and A. subdigitata also exhibited contact toxicity against S. zeamais adults with LD50 values of 40.51 and 76.34 µg/adult, respectively. The results indicated that the two essential oils show potential in terms of fumigant and contact toxicity against grain storage insects. Full article
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Article
Antibacterial, Antifungal and Cytotoxic Activities of Two Flavonoids from Retama raetam Flowers
by Hayet Edziri, Maha Mastouri, Mohamed Ali Mahjoub, Zine Mighri, Aouni Mahjoub and Luc Verschaeve
Molecules 2012, 17(6), 7284-7293; https://doi.org/10.3390/molecules17067284 - 13 Jun 2012
Cited by 93 | Viewed by 7602
Abstract
We have investigated the antibacterial, antifungal and cytotoxic activities of two flavonoids isolated from Retama raetam flowers using the disc diffusion and micro-dilution broth methods. The cytotoxic activity was tested against Hep-2 cells using the MTT assay. The compounds licoflavone C (1 [...] Read more.
We have investigated the antibacterial, antifungal and cytotoxic activities of two flavonoids isolated from Retama raetam flowers using the disc diffusion and micro-dilution broth methods. The cytotoxic activity was tested against Hep-2 cells using the MTT assay. The compounds licoflavone C (1) and derrone (2) were active against Pseudomonas aeruginosa and Escherichia coli (7.81–15.62 µg/mL) and showed important antifungal activity. Strong antifungal activity against Candida species (7.81 µg/mL) was for example found with compound 2. The tested compounds also showed strong cytotoxicity against Hep-2 cells. These two compounds may be interesting antimicrobial agents to be used against infectious diseases caused by many pathogens. Full article
(This article belongs to the Section Natural Products Chemistry)
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283 KiB  
Article
Antioxidant Activity of Various Parts of Cinnamomum cassia Extracted with Different Extraction Methods
by Cheng-Hong Yang, Rong-Xian Li and Li-Yeh Chuang
Molecules 2012, 17(6), 7294-7304; https://doi.org/10.3390/molecules17067294 - 13 Jun 2012
Cited by 103 | Viewed by 10111
Abstract
The aim of this study was to investigate the antioxidant activities of various parts (barks, buds, and leaves) of Cinnamomum cassia extracted with ethanol and supercritical fluid extraction (SFE). For the antioxidant activity comparison, IC50 values of the SFE and ethanol extracts [...] Read more.
The aim of this study was to investigate the antioxidant activities of various parts (barks, buds, and leaves) of Cinnamomum cassia extracted with ethanol and supercritical fluid extraction (SFE). For the antioxidant activity comparison, IC50 values of the SFE and ethanol extracts in the DPPH scavenging assay were 0.562–10.090 mg/mL and 0.072–0.208 mg/mL, and the Trolox equivalent antioxidant capacity (TEAC) values were 6.789–58.335 mmole Trolox/g and 133.039–335.779 mmole Trolox/g, respectively. In addition, the total flavonoid contents were 0.031–1.916 g/ 100 g dry weight of materials (DW) and 2.030–3.348 g/ 100 g DW, and the total phenolic contents were 0.151–2.018 g/ 100 g DW and 6.313–9.534 g/ 100 g DW in the SFE and ethanol extracts, respectively. Based on the results, the ethanol extracts of Cinnamon barks have potential value as an antioxidant substitute and this study also provide a better technique to extract the natural antioxidant substances from C. cassia. Full article
(This article belongs to the Section Natural Products Chemistry)
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245 KiB  
Article
Impact of Soil Field Water Capacity on Secondary Metabolites, Phenylalanine Ammonia-lyase (PAL), Maliondialdehyde (MDA) and Photosynthetic Responses of Malaysian Kacip Fatimah (Labisia pumila Benth)
by Hawa Z. E. Jaafar, Mohd Hafiz Ibrahim and Nur Farhana Mohamad Fakri
Molecules 2012, 17(6), 7305-7322; https://doi.org/10.3390/molecules17067305 - 13 Jun 2012
Cited by 110 | Viewed by 7375
Abstract
A randomized complete block design 2 × 4 experiment was designed and conducted for 15 weeks to characterize the relationships between production of total phenolics, flavonoid, anthocyanin, leaf gas exchange, total chlorophyll, phenylalanine ammonia-lyase (PAL) and malondialdehyde (MDA) activity in two varieties of [...] Read more.
A randomized complete block design 2 × 4 experiment was designed and conducted for 15 weeks to characterize the relationships between production of total phenolics, flavonoid, anthocyanin, leaf gas exchange, total chlorophyll, phenylalanine ammonia-lyase (PAL) and malondialdehyde (MDA) activity in two varieties of Labisia pumila Benth, namely the var. alata and pumila, under four levels of evapotranspiration replacement (ER) (100%; well watered), (75%, moderate water stress), (50%; high water stress) and (25%; severe water stress). The production of total phenolics, flavonoids, anthocyanin, soluble sugar and relative leaf water content was affected by the interaction between varieties and SWC. As the ER levels decreased from 100% to 25%, the production of PAL and MDA activity increased steadily. At the highest (100%) ER L. pumila exhibited significantly higher net photosynthesis, apparent quantum yield, maximum efficiency of photosystem II (fv/fm) and lower dark respiration rates compared to the other treatment. The production of total phenolics, flavonoids and anthocyanin was also found to be higher under high water stress (50% ER replacement) compared to severe water stress (25% ER). From this study, it was observed that as net photosynthesis, apparent quantum yield and chlorophyll content were downregulated under high water stress the production of total phenolics, flavonoids and anthocyanin were upregulated implying that the imposition of high water stress can enhance the medicinal properties of L. pumila Benth. Full article
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388 KiB  
Article
Optimizing the Extraction of Anti-tumor Polysaccharides from the Fruit of Capparis spionosa L. by Response Surface Methodology
by Yu-Bin Ji, Fang Dong, Dong-Bin Ma, Jing Miao, Li-Na Jin, Zhen-Feng Liu and Ling-Wen Zhang
Molecules 2012, 17(6), 7323-7335; https://doi.org/10.3390/molecules17067323 - 14 Jun 2012
Cited by 33 | Viewed by 5585
Abstract
Capparis spionosa L. is a traditional medicinal plant in China and central Asia. In this study, an experiment was designed to investigate the optimization of the extraction of anti-tumor polysaccharides from the fruit of Capparis spionosa L. (CSPS) by response surface methodology (RSM). [...] Read more.
Capparis spionosa L. is a traditional medicinal plant in China and central Asia. In this study, an experiment was designed to investigate the optimization of the extraction of anti-tumor polysaccharides from the fruit of Capparis spionosa L. (CSPS) by response surface methodology (RSM). Four independent variables (extraction temperature, extraction time, ratio of water to sample and extraction cycles) were explored. Meanwhile, the in vivo anti-tumor activity of CSPS was investigated. The results showed that the experimental data could be fitted to a second-order polynomial equation using multiple regression analysis. The optimum extraction conditions were as follows: extraction temperature 92 °C, extraction time 140 min, ratio of water to sample 26 mL/g, and three extraction cycle. Under these conditions, the yield of polysaccharides reached 13.01%, which was comparable to the predicted yield (12.94%, p > 0.05). This indicated that the model was adequate for the extraction process. Additionally, CSPS could prolong the survival time of H22 bearing mice in vivo. The anti-tumor activities of CSPS were dose-dependent. Full article
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410 KiB  
Article
Isolation and Partial Characterization of an Antifungal Protein Produced by Bacillus licheniformis BS-3
by Tang-Bing Cui, Hai-Yun Chai and Li-Xiang Jiang
Molecules 2012, 17(6), 7336-7347; https://doi.org/10.3390/molecules17067336 - 14 Jun 2012
Cited by 29 | Viewed by 6152
Abstract
An antifungal protein produced by Bacillus licheniformis strain BS-3 was purified to homogeneity by ammonium sulfate precipitation, DEAE-52 column chromatography and Sephadex G-75 column chromatography. The purified protein was designated as F2 protein, inhibited the growth of Aspergillus niger, Magnaporthe oryzae and [...] Read more.
An antifungal protein produced by Bacillus licheniformis strain BS-3 was purified to homogeneity by ammonium sulfate precipitation, DEAE-52 column chromatography and Sephadex G-75 column chromatography. The purified protein was designated as F2 protein, inhibited the growth of Aspergillus niger, Magnaporthe oryzae and Rhizoctonia solani. F2 protein was a monomer with approximately molecular weight of 31 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gave a single peak on High Performance Liquid Chromatography (HPLC). Using Rhizoctonia solani as the indicator strain, the EC50 of F2 protein was 35.82 µg/mL, displaying a higher antifungal activity in a range of pH 6.0 to pH 10.0, and at a temperature below 70 °C for 30 min. F2 protein was moderately resistant to hydrolysis by trypsin, proteinase K, after which its relative activities were 41.7% and 59.5%, respectively. F2 protein was assayed using various substrates to determine the enzymatic activities, the results showed the hydrolyzing activity on casein, however, no enzymatic activities on colloidal chitin, CM-cellulose, xylan, M. lysodeikticus, and p-nitrophenyl-N-acetylglucosaminide. Full article
(This article belongs to the Section Natural Products Chemistry)
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Article
Ring-Expansion Reaction of Oximes with Aluminum Reductants
by Hidetsura Cho, Yusuke Iwama, Nakako Mitsuhashi, Kenji Sugimoto, Kentaro Okano and Hidetoshi Tokuyama
Molecules 2012, 17(6), 7348-7355; https://doi.org/10.3390/molecules17067348 - 14 Jun 2012
Cited by 21 | Viewed by 6625
Abstract
The ring-expansion reactions of heterocyclic ketoximes and carbocyclic ketoximes with several reductants such as AlHCl2, AlH3 (alane), LiAlH4, LiAlH(OtBu)3, and (MeOCH2CH2O)2AlH2Na (Red-Al) were examined. Among reductants, [...] Read more.
The ring-expansion reactions of heterocyclic ketoximes and carbocyclic ketoximes with several reductants such as AlHCl2, AlH3 (alane), LiAlH4, LiAlH(OtBu)3, and (MeOCH2CH2O)2AlH2Na (Red-Al) were examined. Among reductants, AlHCl2 (LiAlH4:AlCl3 = 1:3) in cyclopentyl methyl ether (CPME) has been found to be a suitable reagent for the reaction, and the rearranged cyclic secondary amines were obtained in good to excellent yields. Full article
(This article belongs to the Special Issue Heterocycles)
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606 KiB  
Article
A New Method for Production of Chiral 2-Aryl-2-fluoropropanoic Acids Using an Effective Kinetic Resolution of Racemic 2-Aryl-2-fluoropropanoic Acids
by Atsushi Tengeiji and Isamu Shiina
Molecules 2012, 17(6), 7356-7378; https://doi.org/10.3390/molecules17067356 - 14 Jun 2012
Cited by 12 | Viewed by 6474
Abstract
We report a new method for the preparation of chiral 2-aryl-2-fluoropropanoic acids, including 2-fluoroibuprofen, a fluorinated analogue of non-steroidal anti-inflammatory drugs (NSAIDs), by the kinetic resolution of racemic 2-aryl-2-fluoropropanoic acids using enantioselective esterification. By applying pivalic anhydride (Piv2O) as a coupling [...] Read more.
We report a new method for the preparation of chiral 2-aryl-2-fluoropropanoic acids, including 2-fluoroibuprofen, a fluorinated analogue of non-steroidal anti-inflammatory drugs (NSAIDs), by the kinetic resolution of racemic 2-aryl-2-fluoropropanoic acids using enantioselective esterification. By applying pivalic anhydride (Piv2O) as a coupling agent, bis(α-naphthyl)methanol [(α-Np)2CHOH] as an achiral alcohol, and (+)-benzotetramisole (BTM) as a chiral acyl-transfer catalyst, a series of racemic 2-aryl-2-fluoropropanoic acids were kinetically separated to afford the optically active carboxylic acids and the corresponding esters with good to high enantiomeric excesses. This technology can provide a convenient approach to furnish the chiral α-fluorinated drugs containing quaternary carbons at the α-positions in the 2-aryl-2-fluoropropanoic acid structure. Full article
(This article belongs to the Special Issue Asymmetric Catalysis)
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178 KiB  
Communication
Substituted Benzamides Containing Azaspiro Rings as Upregulators of Apolipoprotein A-I Transcription
by Yu Du, Yuan Yang, Wei Jiang, Li Wang, Xiao-Jian Jia, Shu-Yi Si, Xiao-Fang Chen and Bin Hong
Molecules 2012, 17(6), 7379-7386; https://doi.org/10.3390/molecules17067379 - 14 Jun 2012
Cited by 7 | Viewed by 4600
Abstract
Apolipoprotein A-I (Apo A-I) is the principal protein component of high density lipoprotein (HDL), which is generally considered as a potential therapeutic target against atherosclerosis. The understanding of the Apo A-I regulation mechanism has fuelled the development of novel HDL targeted therapeutic approaches. [...] Read more.
Apolipoprotein A-I (Apo A-I) is the principal protein component of high density lipoprotein (HDL), which is generally considered as a potential therapeutic target against atherosclerosis. The understanding of the Apo A-I regulation mechanism has fuelled the development of novel HDL targeted therapeutic approaches. To identify novel agents that can upregulate Apo A-I expression, we performed a cell-based reporter assay to screen 25,600 small molecules. Based on the dataset obtained from screening, a series of novel analogs of substituted benzamides containing azaspiro rings were assessed for their ability to induce the transcription of the Apo A-I gene, and the structure-activity relationship (SAR) around these analogs was also proposed. The results indicated that the trifluoromethyl substituted benzamide containing an azaspiro ring is a promising backbone for designing Apo A-I transcriptional upregulator and could be viable leads for development of new drugs to prevent and treat atherosclerosis in the future. Full article
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Article
Application of 2,3-Naphthalenediamine in Labeling Natural Carbohydrates for Capillary Electrophoresis
by Chien-Yuan Kuo, Shwu-Huey Wang, Chunchi Lin, Sylvain Kuo-Shiang Liao, Wei-Ting Hung, Jim-Min Fang and Wen-Bin Yang
Molecules 2012, 17(6), 7387-7400; https://doi.org/10.3390/molecules17067387 - 15 Jun 2012
Cited by 11 | Viewed by 5370
Abstract
Neutral and acidic monosaccharide components in Ganoderma lucidum polysaccharide are readily labeled with 2,3-naphthalenediamine, and the resulting saccharide-naphthimidazole (NAIM) derivatives are quantified by capillary electrophoresis (CE) in borate buffer. Using sulfated-α-cyclodextrin as the chiral selector, enantiomers of monosaccharide-NAIMs are resolved on CE in [...] Read more.
Neutral and acidic monosaccharide components in Ganoderma lucidum polysaccharide are readily labeled with 2,3-naphthalenediamine, and the resulting saccharide-naphthimidazole (NAIM) derivatives are quantified by capillary electrophoresis (CE) in borate buffer. Using sulfated-α-cyclodextrin as the chiral selector, enantiomers of monosaccharide-NAIMs are resolved on CE in phosphate buffer, allowing a simultaneous determination of the absolute configuration and sugar composition in the mucilage polysaccharide of a medicinal herb Dendrobium huoshanense. Together with the specific enzymatic reactions of various glycoside hydrolases on the NAIM derivatives of glycans, the structures of natural glycans can be deduced from the digestion products identified by CE analysis. Though heparin dissachrides could be successfully derived with the NAIM-labeling method, the heparin derivatives with the same degree of sulfation could not be separated by CE. Full article
(This article belongs to the Section Natural Products Chemistry)
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326 KiB  
Article
A Monoclonal Antibody-Based ELISA for Multiresidue Determination of Avermectins in Milk
by Chunmei Wang, Zhanhui Wang, Wenxiao Jiang, Tiejun Mi and Jianzhong Shen
Molecules 2012, 17(6), 7401-7414; https://doi.org/10.3390/molecules17067401 - 15 Jun 2012
Cited by 12 | Viewed by 5294
Abstract
Due to the widespread use and potential toxicity of avermectins (AVMs), multi-residue monitoring of AVMs in edible tissues, especially in milk, has become increasingly important. With the aim of developing a broad-selective immunoassay for AVMs, a broad-specific monoclonal antibody (Mab) was raised. Based [...] Read more.
Due to the widespread use and potential toxicity of avermectins (AVMs), multi-residue monitoring of AVMs in edible tissues, especially in milk, has become increasingly important. With the aim of developing a broad-selective immunoassay for AVMs, a broad-specific monoclonal antibody (Mab) was raised. Based on this Mab, a homologous indirect enzyme-linked immunosorbent assay (ELISA) for the rapid detection of AVMs in milk was developed. Under the optimized conditions, the IC50 values in assay buffer were estimated to be 3.05 ng/mL for abamectin, 13.10 ng/mL for ivermectin, 38.96 ng/mL for eprinomectin, 61.00 ng/mL for doramectin, 14.38 ng/mL for emamectin benzoate. Detection capability (CCβ) of the ELISA was less than 5 ng/mL and 2 ng/mL in milk samples prepared by simple dilution and solvent extraction, respectively. The optimized ELISA was used to quantify AVMs in milk samples spiked at different amounts. The mean recovery and coefficient of variation (CV) were 95.90% and 15.42%, respectively. The Mab-based ELISA achieved a great improvement in AVMs detection. Results proved this broad-selective ELISA would be useful for the multi-residue determination of AVMs in milk without purification process. Full article
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753 KiB  
Article
Application of 4D-QSAR Studies to a Series of Raloxifene Analogs and Design of Potential Selective Estrogen Receptor Modulators
by Ana Carolina Rennó Sodero, Nelilma Correia Romeiro, Elaine Fontes Ferreira Da Cunha, Uiaran De Oliveira Magalhães, Ricardo Bicca De Alencastro, Carlos Rangel Rodrigues, Lúcio Mendes Cabral, Helena Carla Castro and Magaly Girão Albuquerque
Molecules 2012, 17(6), 7415-7439; https://doi.org/10.3390/molecules17067415 - 15 Jun 2012
Cited by 10 | Viewed by 5649
Abstract
Four-dimensional quantitative structure-activity relationship (4D-QSAR) analysis was applied on a series of 54 2-arylbenzothiophene derivatives, synthesized by Grese and coworkers, based on raloxifene (an estrogen receptor-alpha antagonist), and evaluated as ERa ligands and as inhibitors of estrogen-stimulated proliferation of MCF-7 breast cancer cells. [...] Read more.
Four-dimensional quantitative structure-activity relationship (4D-QSAR) analysis was applied on a series of 54 2-arylbenzothiophene derivatives, synthesized by Grese and coworkers, based on raloxifene (an estrogen receptor-alpha antagonist), and evaluated as ERa ligands and as inhibitors of estrogen-stimulated proliferation of MCF-7 breast cancer cells. The conformations of each analogue, sampled from a molecular dynamics simulation, were placed in a grid cell lattice according to three trial alignments, considering two grid cell sizes (1.0 and 2.0 Å). The QSAR equations, generated by a combined scheme of genetic algorithms (GA) and partial least squares (PLS) regression, were evaluated by “leave-one-out” cross-validation, using a training set of 41 compounds. External validation was performed using a test set of 13 compounds. The obtained 4D-QSAR models are in agreement with the proposed mechanism of action for raloxifene. This study allowed a quantitative prediction of compounds’ potency and supported the design of new raloxifene analogs. Full article
(This article belongs to the Special Issue QSAR and Its Applications)
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Article
NIR Spectroscopic Properties of Aqueous Acids Solutions
by Ahmad Fairuz Omar, Hanafi Atan and Mohd Zubir MatJafri
Molecules 2012, 17(6), 7440-7450; https://doi.org/10.3390/molecules17067440 - 15 Jun 2012
Cited by 31 | Viewed by 5792
Abstract
Acid content is one of the important quality attributes in determining the maturity index of agricultural product, particularly fruits. Despite the fact that much research on the measurement of acidity in fruits through non-destructive spectroscopy analysis at NIR wavelengths between 700 to 1,000 [...] Read more.
Acid content is one of the important quality attributes in determining the maturity index of agricultural product, particularly fruits. Despite the fact that much research on the measurement of acidity in fruits through non-destructive spectroscopy analysis at NIR wavelengths between 700 to 1,000 nm has been conducted, the same response towards individual acids is not well known. This paper presents NIR spectroscopy analysis on aqueous citric, tartaric, malic and oxalic solutions through quantitative analysis by selecting a set of wavelengths that can best be used to measure the pH of the solutions. The aquaphotomics study of the acid solutions has generated R2 above 0.9 for the measurement of all acids. The most important wavelengths for pH are located at 918–925 nm and 990–996 nm, while at 975 nm for water. Full article
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966 KiB  
Short Note
An Oxidized Squalene Derivative from Protium subserratum Engl. (Engl.) Growing in Peru
by John Lokvam and Paul V. A. Fine
Molecules 2012, 17(6), 7451-7457; https://doi.org/10.3390/molecules17067451 - 15 Jun 2012
Cited by 7 | Viewed by 4357
Abstract
Protium subserratum (Burseraceae) is a neotropical tree species that is comprised of several habitat-specific ecotypes having distinct defense chemical profiles. A previously unknown triterpene, 25,30-dicarboxy-26,27,28,29-tetraacetoxy-10,11,14,15-tetrahydrosqualene, was isolated from P. subserratum young leaf tissue of one ecotype growing in Peru. The structure of 1 [...] Read more.
Protium subserratum (Burseraceae) is a neotropical tree species that is comprised of several habitat-specific ecotypes having distinct defense chemical profiles. A previously unknown triterpene, 25,30-dicarboxy-26,27,28,29-tetraacetoxy-10,11,14,15-tetrahydrosqualene, was isolated from P. subserratum young leaf tissue of one ecotype growing in Peru. The structure of 1 was determined by spectroscopic study, including 1 and 2D nuclear magnetic resonance experiments. Full article
(This article belongs to the Section Natural Products Chemistry)
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1009 KiB  
Article
Guanidine Affects Differentially the Twitch Response of Diaphragm, Extensor Digitorum Longus and Soleus Nerve-Muscle Preparations of Mice
by Rosana Ferrari, Léa Rodrigues-Simioni and Maria Alice Da Cruz Höfling
Molecules 2012, 17(6), 7503-7522; https://doi.org/10.3390/molecules17067503 - 15 Jun 2012
Viewed by 5001
Abstract
Guanidine has been used with some success to treat myasthenia gravis and myasthenic syndrome because it increases acetylcholine release at nerve terminals through K+, Na+ and Ca2+ channels-involving mechanisms. Currently, guanidine derivatives have been proposed for treatment of several [...] Read more.
Guanidine has been used with some success to treat myasthenia gravis and myasthenic syndrome because it increases acetylcholine release at nerve terminals through K+, Na+ and Ca2+ channels-involving mechanisms. Currently, guanidine derivatives have been proposed for treatment of several diseases. Studies aimed at providing new insights to the drug are relevant. Experimentally, guanidine (10 mM) induces on mouse phrenic nerve-diaphragm (PND) preparations neurotransmission facilitation followed by blockade and a greatest secondary facilitation after its removal from bath. Herein, we hypothesized that this peculiar triphasic response may differ in muscles with distinct twitch/metabolic characteristics. Morphological alterations and contractile response of PND, extensor digitorum longus (EDL) and soleus (SOL) preparations incubated with guanidine (10 mM) for 15, 30, 60 min were analyzed. Guanidine concentrations of 5 mM (for PND and EDL) and 1 mM (for EDL) were also tested. Guanidine triphasic effect was only observed on PND regardless the concentration. The morphological alterations in muscle tissue varied along time but did not impede the PND post-wash facilitation. Higher doses (20–25 mM) did not increase EDL or SOL neurotransmission. The data suggest a complex mechanism likely dependent on the metabolic/contractile muscle phenotype; muscle fiber types and density/type of ion channels, sarcoplasmic reticulum and mitochondria organization may have profound impact on the levels and isoform expression pattern of Ca2+ regulatory membrane proteins so reflecting regulation of calcium handling and contractile response in different types of muscle. Full article
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234 KiB  
Communication
Enantioselective Michael Addition of 3-Aryl-Substituted Oxindoles to Methyl Vinyl Ketone Catalyzed by a Binaphthyl-Modified Bifunctional Organocatalyst
by Hyun Joo Lee, Saet Byeol Woo and Dae Young Kim
Molecules 2012, 17(6), 7523-7532; https://doi.org/10.3390/molecules17067523 - 18 Jun 2012
Cited by 28 | Viewed by 6113
Abstract
The enantioselective conjugate addition reaction of 3-aryl-substituted oxindoles with methyl vinyl ketone promoted by binaphthyl-modified bifunctional organocatalysts was investigated. The corresponding Michael adducts, containing a quaternary center at the C3-position of the oxindoles, were generally obtained in high yields with excellent enantioselectivities (up [...] Read more.
The enantioselective conjugate addition reaction of 3-aryl-substituted oxindoles with methyl vinyl ketone promoted by binaphthyl-modified bifunctional organocatalysts was investigated. The corresponding Michael adducts, containing a quaternary center at the C3-position of the oxindoles, were generally obtained in high yields with excellent enantioselectivities (up to 91% ee). Full article
(This article belongs to the Special Issue Asymmetric Catalysis)
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180 KiB  
Article
The Joint Action of Destruxins and Botanical Insecticides (Rotenone, Azadirachtin and Paeonolum) Against the Cotton Aphid, Aphis gossypii Glover
by Fei Yi, Chunhua Zou, Qiongbo Hu and Meiying Hu
Molecules 2012, 17(6), 7533-7542; https://doi.org/10.3390/molecules17067533 - 18 Jun 2012
Cited by 29 | Viewed by 5381
Abstract
The joint action of destruxins and three botanical insecticides, rotenone (Rot), azadirachtin (Aza) and paeonolum (Pae) against the cotton aphid, Aphis gossypii, was bioassayed. In laboratory experiment, several synergistic groups of destruxins with botanical insecticides were found by means of Sun’s Co-toxicity [...] Read more.
The joint action of destruxins and three botanical insecticides, rotenone (Rot), azadirachtin (Aza) and paeonolum (Pae) against the cotton aphid, Aphis gossypii, was bioassayed. In laboratory experiment, several synergistic groups of destruxins with botanical insecticides were found by means of Sun’s Co-toxicity Coefficients (CTC) and Finney’s Synergistic Coefficient (SC). The best synergistic effect was discovered in the ratio group Des/Rot 1/9 with the CTC or SC and LC50 values of 479.93 or 4.8 and 0.06 μg/mL, respectively. The second and third synergistic effects were recorded in the ratio groups Des/Rot 7/3 and 9/1. Although the ratio groups Des/Aza 6/4, Des/Pae 4/6, 3/7 and 2/8 indicated synergism by Sun’s CTC, they were determined as additive actions by Finney’s SC. Additive actions were also found in most of the ratio groups, but antagonism were recorded only in three ratio groups: Des/Pae 9/1, 7/3 and 6/4. In greenhouse tests, the highest mortality was 98.9% with the treatment Des/Rot 1/9 at 0.60 μg/mL, meanwhile, the treatments Des/Pae 4/6 and Des/Aza 6/4 had approximately 88% mortality. Full article
(This article belongs to the Section Natural Products Chemistry)
287 KiB  
Article
Design, Synthesis and Antiviral Potential of 14-Aryl/Heteroaryl-14H-dibenzo[a,j]xanthenes Using an Efficient Polymer-Supported Catalyst
by Kalla Reddi Mohan Naidu, Balam Satheesh Krishna, Mungara Anil Kumar, Palanisamy Arulselvan, Shaik Ibrahim Khalivulla and Ola Lasekan
Molecules 2012, 17(6), 7543-7555; https://doi.org/10.3390/molecules17067543 - 18 Jun 2012
Cited by 79 | Viewed by 6587
Abstract
Polyethyleneglycol bound sulfonic acid (PEG-OSO3H), a chlorosulphonic acid-modified polyethylene glycol was successfully used as an efficient and eco-friendly polymeric catalyst in the synthesis of 14-aryl/heteroaryl-14H-dibenzo[a,j]xanthenes obtained from the reaction of 2-naphthol and carbonyl compounds under solvent-free conditions [...] Read more.
Polyethyleneglycol bound sulfonic acid (PEG-OSO3H), a chlorosulphonic acid-modified polyethylene glycol was successfully used as an efficient and eco-friendly polymeric catalyst in the synthesis of 14-aryl/heteroaryl-14H-dibenzo[a,j]xanthenes obtained from the reaction of 2-naphthol and carbonyl compounds under solvent-free conditions with short reaction times and excellent yields. The biological properties of these synthesized title compounds revealed that compounds 3b, 3c, 3f and 3i showed highly significant anti-viral activity against tobacco mosaic virus. Full article
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335 KiB  
Article
Synthesis and Biological Evaluation of Novel Furozan-Based Nitric Oxide-Releasing Derivatives of Oridonin as Potential Anti-Tumor Agents
by Dahong Li, Lei Wang, Hao Cai, Yihua Zhang and Jinyi Xu
Molecules 2012, 17(6), 7556-7568; https://doi.org/10.3390/molecules17067556 - 18 Jun 2012
Cited by 36 | Viewed by 6816
Abstract
To search for novel nitric oxide (NO) releasing anti-tumor agents, a series of novel furoxan/oridonin hybrids were designed and synthesized. Firstly, the nitrate/nitrite levels in the cell lysates were tested by a Griess assay and the results showed that these furoxan-based NO-releasing derivatives [...] Read more.
To search for novel nitric oxide (NO) releasing anti-tumor agents, a series of novel furoxan/oridonin hybrids were designed and synthesized. Firstly, the nitrate/nitrite levels in the cell lysates were tested by a Griess assay and the results showed that these furoxan-based NO-releasing derivatives could produce high levels of NO in vitro. Then the anti-proliferative activity of these hybrids against four human cancer cell lines was also determined, among which, 9h exhibited the most potential anti-tumor activity with IC50 values of 1.82 µM against K562, 1.81 µM against MGC-803 and 0.86 µM against Bel-7402, respectively. Preliminary structure-activity relationship was concluded based on the experimental data obtained. These results suggested that NO-donor/natural product hybrids may provide a promising approach for the discovery of novel anti-tumor agents. Full article
(This article belongs to the Collection Bioactive Compounds)
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365 KiB  
Article
Synthesis of Main-Chain Chiral Quaternary Ammonium Polymers for Asymmetric Catalysis Using Quaternization Polymerization
by Naoki Haraguchi, Parbhej Ahamed, Md. Masud Parvez and Shinichi Itsuno
Molecules 2012, 17(6), 7569-7583; https://doi.org/10.3390/molecules17067569 - 19 Jun 2012
Cited by 17 | Viewed by 7306
Abstract
Main-chain chiral quaternary ammonium polymers were successfully synthesized by the quaternization polymerization of cinchonidine dimer with dihalides. The polymerization occurred smoothly under optimized conditions to give novel type of main-chain chiral quaternary ammonium polymers. The catalytic activity of the polymeric chiral organocatalysts was [...] Read more.
Main-chain chiral quaternary ammonium polymers were successfully synthesized by the quaternization polymerization of cinchonidine dimer with dihalides. The polymerization occurred smoothly under optimized conditions to give novel type of main-chain chiral quaternary ammonium polymers. The catalytic activity of the polymeric chiral organocatalysts was investigated on the asymmetric benzylation of N-(diphenylmethylidene)glycine tert-butyl ester. Full article
(This article belongs to the Special Issue Asymmetric Catalysis)
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282 KiB  
Article
Effect of Acid and Base Catalyzed Hydrolysis on the Yield of Phenolics and Antioxidant Activity of Extracts from Germinated Brown Rice (GBR)
by Ismaila Muhammad Sani, Shahid Iqbal, Kim Wei Chan and Maznah Ismail
Molecules 2012, 17(6), 7584-7594; https://doi.org/10.3390/molecules17067584 - 19 Jun 2012
Cited by 45 | Viewed by 6860
Abstract
The influence of both acidic and basic hydrolysis on the yield, total phenolic content and antioxidative capacity of methanolic extract of germinated brown rice (GBR) was studied. Total phenolic content (TPC), total flavonoid content (TFC), 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical [...] Read more.
The influence of both acidic and basic hydrolysis on the yield, total phenolic content and antioxidative capacity of methanolic extract of germinated brown rice (GBR) was studied. Total phenolic content (TPC), total flavonoid content (TFC), 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation scavenging, and ferric reducing antioxidant power (FRAP) tests were used for the measurement of antioxidant ability. There was a significant difference (p < 0.05) in the TPC and DPPH radical scavenging assay results when comparing neutral with acidic and basic catalysed hydrolysis. The yield of the crude extract was slightly higher in acidic hydrolysis than in basic hydrolysis (p > 0.05). The TPC and TFC were highest in acidic hydrolysis. A significant correlation was observed between ABTS radical cation scavenging and FRAP. The antioxidant activity measured using DPPH radical scavenging assay showed high activity in acidic hydrolysis, while the ABTS radical cationscavenging activity and FRAP showed the highest values in basic hydrolysis. The samples were further evaluated using HPLC to determine the individual phenolic concentrations in different hydrolytic media contributing to the antioxidant effects. This study revealed that acidic and basic hydrolysis can improve the yield, phenolic content, and antioxidant activity of germinated brown rice. Full article
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1460 KiB  
Article
Down Regulation of CIAPIN1 Reverses Multidrug Resistance in Human Breast Cancer Cells by Inhibiting MDR1
by Dan Lu, Zhibo Xiao, Wenxiu Wang, Yuqing Xu, Shujian Gao, Lili Deng, Wen He, Yu Yang, Xiaofei Guo and Xuemei Wang
Molecules 2012, 17(6), 7595-7611; https://doi.org/10.3390/molecules17067595 - 20 Jun 2012
Cited by 21 | Viewed by 5811
Abstract
Cytokine-induced apoptosis inhibitor 1 (CIAPIN1), initially named anamorsin, a newly indentified antiapoptotic molecule is a downstream effector of the receptor tyrosine kinase-Ras signaling pathway. Current study has revealed that CIAPIN1 may have wide and important functions, especially due to its close correlations with [...] Read more.
Cytokine-induced apoptosis inhibitor 1 (CIAPIN1), initially named anamorsin, a newly indentified antiapoptotic molecule is a downstream effector of the receptor tyrosine kinase-Ras signaling pathway. Current study has revealed that CIAPIN1 may have wide and important functions, especially due to its close correlations with malignant tumors. However whether or not it is involved in the multi-drug resistance (MDR) process of breast cancer has not been elucidated. To explore the effect of CIAPIN1 on MDR, we examined the expression of P-gp and CIAPIN1 by immunohistochemistry and found there was positive correlation between them. Then we successfully interfered with RNA translation by the infection of siRNA of CIAPIN1 into MCF7/ADM breast cancer cell lines through a lentivirus, and the expression of the target gene was significantly inhibited. After RNAi the drug resistance was reduced significantly and the expression of MDR1mRNA and P-gp in MCF7/ADM cell lines showed a significant decrease. Also the expression of P53 protein increased in a statistically significant way (p ≤ 0.01) after RNAi exposure. In addition, flow cytometry analysis reveals that cell cycle and anti-apoptotic enhancing capability of cells changed after RNAi treatment. These results suggested CIAPIN1 may participate in breast cancer MDR by regulating MDR1 and P53 expression, changing cell cycle and enhancing the anti-apoptotic capability of cells. Full article
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Review

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533 KiB  
Review
Embryonic Stem Cell Markers
by Wenxiu Zhao, Xiang Ji, Fangfang Zhang, Liang Li and Lan Ma
Molecules 2012, 17(6), 6196-6236; https://doi.org/10.3390/molecules17066196 - 25 May 2012
Cited by 127 | Viewed by 15564
Abstract
Embryonic stem cell (ESC) markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES [...] Read more.
Embryonic stem cell (ESC) markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM) technique and magnetic cell sorting (MACS) are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs), which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells. Full article
(This article belongs to the Section Molecular Diversity)
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592 KiB  
Review
Antiproliferative and Molecular Mechanism of Eugenol-Induced Apoptosis in Cancer Cells
by Saravana Kumar Jaganathan and Eko Supriyanto
Molecules 2012, 17(6), 6290-6304; https://doi.org/10.3390/molecules17066290 - 25 May 2012
Cited by 147 | Viewed by 15060
Abstract
Phenolic phytochemicals are a broad class of nutraceuticals found in plants which have been extensively researched by scientists for their health-promoting potential. One such a compound which has been comprehensively used is eugenol (4-allyl-2-methoxyphenol), which is the active component of Syzigium aromaticum (cloves). [...] Read more.
Phenolic phytochemicals are a broad class of nutraceuticals found in plants which have been extensively researched by scientists for their health-promoting potential. One such a compound which has been comprehensively used is eugenol (4-allyl-2-methoxyphenol), which is the active component of Syzigium aromaticum (cloves). Aromatic plants like nutmeg, basil, cinnamon and bay leaves also contain eugenol. Eugenol has a wide range of applications like perfumeries, flavorings, essential oils and in medicine as a local antiseptic and anesthetic. Increasing volumes of literature showed eugenol possesses antioxidant, antimutagenic, antigenotoxic, anti-inflammatory and anticancer properties. Molecular mechanism of eugenol-induced apoptosis in melanoma, skin tumors, osteosarcoma, leukemia, gastric and mast cells has been well documented. This review article will highlight the antiproliferative activity and molecular mechanism of the eugenol induced apoptosis against the cancer cells and animal models. Full article
(This article belongs to the Section Natural Products Chemistry)
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410 KiB  
Review
Chemistry of Fullerene Epoxides: Synthesis, Structure, and Nucleophilic Substitution-Addition Reactivity
by Yusuke Tajima, Kazumasa Takeshi, Yasuo Shigemitsu and Youhei Numata
Molecules 2012, 17(6), 6395-6414; https://doi.org/10.3390/molecules17066395 - 25 May 2012
Cited by 27 | Viewed by 7292
Abstract
Fullerene epoxides, C60On, having epoxide groups directly attached to the fullerene cage, constitute an interesting class of fullerene derivatives. In particular, the chemical transformations of fullerene epoxides are expected to play an important role in the development of functionalized [...] Read more.
Fullerene epoxides, C60On, having epoxide groups directly attached to the fullerene cage, constitute an interesting class of fullerene derivatives. In particular, the chemical transformations of fullerene epoxides are expected to play an important role in the development of functionalized fullerenes. This is because such transformations can readily afford a variety of mono- or polyfunctionalized fullerene derivatives while conserving the epoxy ring arrangement on the fullerene surface, as seen in representative regioisomeric fullerene polyepoxides. The first part of this review addresses the synthesis and structural characterization of fullerene epoxides. The formation of fullerene epoxides through different oxidation reactions is then explored. Adequate characterization of the isolated fullerene epoxides was achieved by concerted use of NMR and LC-MS techniques. The second part of this review addresses the substitution of fullerene epoxides in the presence of a Lewis acid catalyst. Most major substitution products have been isolated as pure compounds and their structures established through spectroscopic methods. The correlation between the structure of the substitution product and the oxygenation pattern of the starting materials allows elucidation of the mechanistic features of this transformation. This approach promises to lead to rigorous regioselective production of various fullerene derivatives for a wide range of applications. Full article
(This article belongs to the Special Issue Fullerene Chemistry)
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316 KiB  
Review
The Role of Bioactive Compounds on the Promotion of Neurite Outgrowth
by Sandeep Vasant More, Sushruta Koppula, In-Su Kim, Hemant Kumar, Byung-Wook Kim and Dong-Kug Choi
Molecules 2012, 17(6), 6728-6753; https://doi.org/10.3390/molecules17066728 - 04 Jun 2012
Cited by 64 | Viewed by 8218
Abstract
Neurite loss is one of the cardinal features of neuronal injury. Apart from neuroprotection, reorganization of the lost neuronal network in the injured brain is necessary for the restoration of normal physiological functions. Neuritogenic activity of endogenous molecules in the brain such as [...] Read more.
Neurite loss is one of the cardinal features of neuronal injury. Apart from neuroprotection, reorganization of the lost neuronal network in the injured brain is necessary for the restoration of normal physiological functions. Neuritogenic activity of endogenous molecules in the brain such as nerve growth factor is well documented and supported by scientific studies which show innumerable compounds having neurite outgrowth activity from natural sources. Since the damaged brain lacks the reconstructive capacity, more efforts in research are focused on the identification of compounds that promote the reformation of neuronal networks. An abundancy of natural resources along with the corresponding activity profiles have shown promising results in the field of neuroscience. Recently, importance has also been placed on understanding neurite formation by natural products in relation to neuronal injury. Arrays of natural herbal products having plentiful active constituents have been found to enhance neurite outgrowth. They act synergistically with neurotrophic factors to promote neuritogenesis in the diseased brain. Therefore use of natural products for neuroregeneration provides new insights in drug development for treating neuronal injury. In this study, various compounds from natural sources with potential neurite outgrowth activity are reviewed in experimental models. Full article
(This article belongs to the Collection Bioactive Compounds)
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599 KiB  
Review
Eugenol—From the Remote Maluku Islands to the International Market Place: A Review of a Remarkable and Versatile Molecule
by Guy P. Kamatou, Ilze Vermaak and Alvaro M. Viljoen
Molecules 2012, 17(6), 6953-6981; https://doi.org/10.3390/molecules17066953 - 06 Jun 2012
Cited by 374 | Viewed by 32836
Abstract
Eugenol is a major volatile constituent of clove essential oil obtained through hydrodistillation of mainly Eugenia caryophyllata (=Syzygium aromaticum) buds and leaves. It is a remarkably versatile molecule incorporated as a functional ingredient in numerous products and has found application in [...] Read more.
Eugenol is a major volatile constituent of clove essential oil obtained through hydrodistillation of mainly Eugenia caryophyllata (=Syzygium aromaticum) buds and leaves. It is a remarkably versatile molecule incorporated as a functional ingredient in numerous products and has found application in the pharmaceutical, agricultural, fragrance, flavour, cosmetic and various other industries. Its vast range of pharmacological activities has been well-researched and includes antimicrobial, anti-inflammatory, analgesic, anti-oxidant and anticancer activities, amongst others. In addition, it is widely used in agricultural applications to protect foods from micro-organisms during storage, which might have an effect on human health, and as a pesticide and fumigant. As a functional ingredient, it is included in many dental preparations and it has also been shown to enhance skin permeation of various drugs. Eugenol is considered safe as a food additive but due to the wide range of different applications, extensive use and availability of clove oil, it is pertinent to discuss the general toxicity with special reference to contact dermatitis. This review summarises the pharmacological, agricultural and other applications of eugenol with specific emphasis on mechanism of action as well as toxicity data. Full article
(This article belongs to the Collection Bioactive Compounds)
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924 KiB  
Review
Coordination Modes and Different Hapticities for Fullerene Organometallic Complexes
by Delia Soto and Roberto Salcedo
Molecules 2012, 17(6), 7151-7168; https://doi.org/10.3390/molecules17067151 - 12 Jun 2012
Cited by 34 | Viewed by 7133
Abstract
The different coordination modes in fullerene organometallic complexes are reviewed. The main modes are η2 and η5, but there are some interesting studies about the other four, all of them are revised in order to show which is the state of art of [...] Read more.
The different coordination modes in fullerene organometallic complexes are reviewed. The main modes are η2 and η5, but there are some interesting studies about the other four, all of them are revised in order to show which is the state of art of this kind of compounds with the respect of the hapticity. Full article
(This article belongs to the Special Issue Fullerene Chemistry)
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482 KiB  
Review
Hypervalent Nonbonded Interactions of a Divalent Sulfur Atom. Implications in Protein Architecture and the Functions
by Michio Iwaoka and Noriyoshi Isozumi
Molecules 2012, 17(6), 7266-7283; https://doi.org/10.3390/molecules17067266 - 13 Jun 2012
Cited by 117 | Viewed by 7896
Abstract
In organic molecules a divalent sulfur atom sometimes adopts weak coordination to a proximate heteroatom (X). Such hypervalent nonbonded S···X interactions can control the molecular structure and chemical reactivity of organic molecules, as well as their assembly and packing in the solid state. [...] Read more.
In organic molecules a divalent sulfur atom sometimes adopts weak coordination to a proximate heteroatom (X). Such hypervalent nonbonded S···X interactions can control the molecular structure and chemical reactivity of organic molecules, as well as their assembly and packing in the solid state. In the last decade, similar hypervalent interactions have been demonstrated by statistical database analysis to be present in protein structures. In this review, weak interactions between a divalent sulfur atom and an oxygen or nitrogen atom in proteins are highlighted with several examples. S···O interactions in proteins showed obviously different structural features from those in organic molecules (i.e., πO → σS* versus nO → σS* directionality). The difference was ascribed to the HOMO of the amide group, which expands in the vertical direction (πO) rather than in the plane (nO). S···X interactions in four model proteins, phospholipase A2 (PLA2), ribonuclease A (RNase A), insulin, and lysozyme, have also been analyzed. The results suggested that S···X interactions would be important factors that control not only the three-dimensional structure of proteins but also their functions to some extent. Thus, S···X interactions will be useful tools for protein engineering and the ligand design. Full article
(This article belongs to the Special Issue Hypervalent Compounds)
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1121 KiB  
Review
Ionic Liquids — Promising but Challenging Solvents for Homogeneous Derivatization of Cellulose
by Martin Gericke, Pedro Fardim and Thomas Heinze
Molecules 2012, 17(6), 7458-7502; https://doi.org/10.3390/molecules17067458 - 15 Jun 2012
Cited by 289 | Viewed by 15010
Abstract
In the past decade, ionic liquids (ILs) have received enormous interest as solvents for cellulose. They have been studied intensively for fractionation and biorefining of lignocellulosic biomass, for dissolution of the polysaccharide, for preparation of cellulosic fibers, and in particular as reaction media [...] Read more.
In the past decade, ionic liquids (ILs) have received enormous interest as solvents for cellulose. They have been studied intensively for fractionation and biorefining of lignocellulosic biomass, for dissolution of the polysaccharide, for preparation of cellulosic fibers, and in particular as reaction media for the homogeneous preparation of highly engineered polysaccharide derivatives. ILs show great potential for application on a commercial scale regarding recyclability, high dissolution power, and their broad structural diversity. However, a critical analysis reveals that these promising features are combined with serious drawbacks that need to be addressed in order to utilize ILs for the efficient synthesis of cellulose derivatives. This review presents a comprehensive overview about chemical modification of cellulose in ILs. Difficulties encountered thereby are discussed critically and current as well as future developments in this field of polysaccharide research are outlined. Full article
(This article belongs to the Collection Ionic Liquids)
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Other

Jump to: Research, Review

115 KiB  
Correction
Xiao Han, et al., GHGKHKNK Octapeptide (P-5m) Inhibits Metastasis of HCCLM3 Cell Lines via Regulation of MMP-2 Expression in in Vitro and in Vivo Studies. Molecules, 2012, 17, 1357-1372
by Xiao Han, Dong-Mei Yan, Xiang-Feng Zhao, Hiroshi Matsuura, Wei-Guang Ding, Peng Li, Shuang Jiang, Bai-Rong Du, Pei-Ge Du and Xun Zhu
Molecules 2012, 17(6), 6996; https://doi.org/10.3390/molecules17066996 - 06 Jun 2012
Viewed by 4538
Abstract
The authors wish to make the following correction to this paper [1]: the correct name of the fourth author is Hiroshi Matsuura. [...] Full article
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