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Molecules, Volume 14, Issue 4 (April 2009), Pages 1342-1651

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Open AccessArticle Evodiamine Stabilizes Topoisomerase I-DNA Cleavable Complex to Inhibit Topoisomerase I Activity
Molecules 2009, 14(4), 1342-1352; doi:10.3390/molecules14041342
Received: 21 February 2009 / Revised: 13 March 2009 / Accepted: 18 March 2009 / Published: 27 March 2009
Cited by 21 | PDF Full-text (248 KB) | HTML Full-text | XML Full-text
Abstract
Evodiamine (EVO), an alkaloidal compound isolated from Evodia rutaecarpa (Juss.), has been reported to affect many physiological functions. Topoisomerase inhibitors have been developed in a variety of clinical applications. In the present study, we report the topoisomerase I (TopI) inhibitory activity
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Evodiamine (EVO), an alkaloidal compound isolated from Evodia rutaecarpa (Juss.), has been reported to affect many physiological functions. Topoisomerase inhibitors have been developed in a variety of clinical applications. In the present study, we report the topoisomerase I (TopI) inhibitory activity of EVO, which may have properties that lead to improved therapeutic benefits. EVO is able to inhibit supercoiled plasmid DNA relaxation catalyzed by TopI. Upon treatment 0~10 μM EVO TopI was depleted in MCF-7 breast cancer cells in a concentration-dependent and time-dependent manner in 0~120 min. A K-SDS precipitation assay was performed to measure the extent of Top I-trapped chromosomal DNA. The ability of EVO to cause the formation of a TopI-DNA complex increased in a concentration-dependent manner, in that the DNA trapped increased by 24.2% in cells treated with 30 μM. The results suggest that EVO inhibits TopI by stabilizing the enzyme and DNA covalent complex. Full article
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Open AccessArticle Syntheses, Spectroscopic and AFM Characterization of Some Manganese Porphyrins and Their Hybrid Silica Nanomaterials
Molecules 2009, 14(4), 1370-1388; doi:10.3390/molecules14041370
Received: 23 February 2009 / Revised: 19 March 2009 / Accepted: 26 March 2009 / Published: 27 March 2009
Cited by 24 | PDF Full-text (728 KB) | HTML Full-text | XML Full-text
Abstract
The present work is concerned with the manganese complexes of 5,10,15,20-tetraphenylporphyrin and of 5,10,15,20-tetra(3-hydroxyphenyl)porphyrin, which were prepared by metallation of the corresponding porphyrin ligands, and the study of their spectroscopic and photophysical behavior under strongly acidic and alkaline conditions. The second objective was
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The present work is concerned with the manganese complexes of 5,10,15,20-tetraphenylporphyrin and of 5,10,15,20-tetra(3-hydroxyphenyl)porphyrin, which were prepared by metallation of the corresponding porphyrin ligands, and the study of their spectroscopic and photophysical behavior under strongly acidic and alkaline conditions. The second objective was to obtain and study some new hybrid materials, with special optoelectronic and surface properties, by impregnation of silica gels obtained by one step acid and by two steps acid-base catalysis with these Mn-porphyrins. The resulting nanomaterials exhibited interesting bathochromic and hyperchromic effects of their second band in the emission spectra in comparison with the Mn-porphyrins and also they have distinct orientation of the aggregates on surfaces, as shown by AFM images, making them useful for applications in medicine, formulation of sensors and for environmental-friendly catalysts for photodegradation of organic compounds. Full article
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Open AccessArticle Antimalarial and Cytotoxic Phenolic Compounds from Cratoxylum maingayi and Cratoxylum cochinchinense
Molecules 2009, 14(4), 1389-1395; doi:10.3390/molecules14041389
Received: 13 February 2009 / Revised: 23 March 2009 / Accepted: 23 March 2009 / Published: 30 March 2009
Cited by 13 | PDF Full-text (102 KB) | HTML Full-text | XML Full-text
Abstract
Nine phenolic compounds isolated from Cratoxylum maingayi and C. cochinchinense were evaluated for anti-malarial activity against Plasmodium falciparum, and for cytotoxic activity against the NCI-H187 (human small cell lung cancer) cancer cell line. Formoxanthone C (3) was found to be the most
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Nine phenolic compounds isolated from Cratoxylum maingayi and C. cochinchinense were evaluated for anti-malarial activity against Plasmodium falciparum, and for cytotoxic activity against the NCI-H187 (human small cell lung cancer) cancer cell line. Formoxanthone C (3) was found to be the most active against the NCI-H187 cancer cell line, with an IC50 of 0.22 mg/mL, while vismione B (7) had the highest activity against Plasmodium falciparum, with an IC50 of 0.66 mg/mL. Full article
Open AccessArticle A New Insecticidal Sesquiterpene Ester from Celastrus Angulatus
Molecules 2009, 14(4), 1396-1403; doi:10.3390/molecules14041396
Received: 12 March 2009 / Revised: 23 March 2009 / Accepted: 27 March 2009 / Published: 30 March 2009
Cited by 10 | PDF Full-text (248 KB) | HTML Full-text | XML Full-text
Abstract
A new sesquiterpene polyol ester with a β-dihydroagarofuran skeleton, NW37 (1), and three known compounds NW13 (2), NW16 (3) and NW35 (4) were isolated by bioassay-guided fractionation from the highly polar MeOH extracts of the root bark of Celastrus angulatus. Their chemical
[...] Read more.
A new sesquiterpene polyol ester with a β-dihydroagarofuran skeleton, NW37 (1), and three known compounds NW13 (2), NW16 (3) and NW35 (4) were isolated by bioassay-guided fractionation from the highly polar MeOH extracts of the root bark of Celastrus angulatus. Their chemical structures were elucidated mainly by analyses of MS and NMR spectral data. The insecticidal activity of compound 1 against 4th instar Mythimna separata larvae with a KD50 value of 252.3 μg·g-1 was demonstrated. Full article
Open AccessArticle Molecular Docking Studies and Anti-enzymatic Activities of Thai Mango Seed Kernel Extract Against Snake Venoms
Molecules 2009, 14(4), 1404-1422; doi:10.3390/molecules14041404
Received: 16 January 2009 / Revised: 26 March 2009 / Accepted: 30 March 2009 / Published: 31 March 2009
Cited by 21 | PDF Full-text (957 KB) | HTML Full-text | XML Full-text
Abstract
The ethanolic extract from seed kernels of Thai mango (MSKE) (Mangifera indica L. cv. ‘Fahlun’) (Anacardiaceae) and its major phenolic principle (pentagalloyl glucopyranose) exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase A2 (PLA2), hyaluronidase and L-amino acid oxidase
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The ethanolic extract from seed kernels of Thai mango (MSKE) (Mangifera indica L. cv. ‘Fahlun’) (Anacardiaceae) and its major phenolic principle (pentagalloyl glucopyranose) exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase A2 (PLA2), hyaluronidase and L-amino acid oxidase (LAAO) of Calloselasma rhodostoma (CR) and Naja naja kaouthia (NK)venoms by in vitro tests. The anti-hemorrhagic and anti-dermonecrotic activities of MSKE against both venoms were clearly supported by in vivo tests. Molecular docking studies indicated that the phenolic molecules of the MSKE could selectively bind to the active sites or their proximity, or modify conserved residues that are critical for the catalysis of PLA2, and selectively bind to the LAAO binding pocket of both CR and NK venoms and thereby inhibit their enzymatic activities. The results imply a potential use of MSKE against snake venoms. Full article
(This article belongs to the Special Issue Phenolics and Polyphenolics)
Open AccessCommunication Ultrasound Promoted Synthesis of Bis(substituted pyrazol-4-ylcarbonyl)-Substituted Thioureas
Molecules 2009, 14(4), 1423-1428; doi:10.3390/molecules14041423
Received: 28 February 2009 / Revised: 15 March 2009 / Accepted: 23 March 2009 / Published: 31 March 2009
Cited by 13 | PDF Full-text (200 KB) | HTML Full-text | XML Full-text
Abstract
A series of novel bis(substituted pyrazol-4-ylcarbonyl)-substituted thioureas have been synthesized by the reactions of substituted pyrazol-4-ylcarbonyl isothiocyanates with different diamines under ultrasound irradiation and classical heating method at 20-25 °C. In general, substantial improvement in rates and modest yields increases were observed when
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A series of novel bis(substituted pyrazol-4-ylcarbonyl)-substituted thioureas have been synthesized by the reactions of substituted pyrazol-4-ylcarbonyl isothiocyanates with different diamines under ultrasound irradiation and classical heating method at 20-25 °C. In general, substantial improvement in rates and modest yields increases were observed when reactions were carried out under sonication, compared with the classical heating method. The structures of these compounds have been elucidated by elemental and spectral (IR, 1H-NMR) analysis. Full article
Open AccessArticle Synthesis of New Naphtho[2,3-f]quinoxaline-2,7,12(1H)-trione and Anthra-9,10-quinone Dyes from Furan-2,3-diones
Molecules 2009, 14(4), 1429-1437; doi:10.3390/molecules14041429
Received: 11 March 2009 / Revised: 26 March 2009 / Accepted: 30 March 2009 / Published: 2 April 2009
Cited by 2 | PDF Full-text (196 KB) | HTML Full-text | XML Full-text
Abstract Novel naphtho[2,3-f]quinoxaline-2,7,12(1H)-trione and anthra-9,10-quinone dyes were synthesized in good yield from furan-2,3-diones using 1,2-diaminoanthra-9,10-quinone and 1,4-diaminoanthra-9,10-quinone. The chromophores were characterized by molecular spectroscopy methods. Full article
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Open AccessArticle Chemical Composition and Biological Activities of Essential Oil from Salvia sclarea Plants Regenerated in vitro
Molecules 2009, 14(4), 1438-1447; doi:10.3390/molecules14041438
Received: 27 January 2009 / Revised: 23 February 2009 / Accepted: 26 February 2009 / Published: 2 April 2009
Cited by 29 | PDF Full-text (161 KB) | HTML Full-text | XML Full-text
Abstract
The essential oils obtained by hydrodistillation of dried aerial parts of Salvia sclarea L. plants, regenerated in vitro and reproduced from seeds, were analyzed by GC and GC-MS. The oils from in vitro and in vivo plants were compared in respect to their
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The essential oils obtained by hydrodistillation of dried aerial parts of Salvia sclarea L. plants, regenerated in vitro and reproduced from seeds, were analyzed by GC and GC-MS. The oils from in vitro and in vivo plants were compared in respect to their chemical composition as well as antimicrobial and cytotoxic activities. The chemical profiles of both oils were very similar, although the yield of essential oil from in vitro plants was lower (0.1%, v/w) than the oil yield isolated from in vivo S. sclarea plants (0.2%, v/w). Both oils showed antimicrobial and cytotoxic activity. The oil from in vitro regenerated plants of S. sclarea exhibited stronger cytotoxic action against NALM-6 cell lines in comparison with the essential oil from in vivo plants. Full article
Open AccessArticle QSAR Studies on N-aryl Derivative Activity Towards Alzheimer’s Disease
Molecules 2009, 14(4), 1448-1455; doi:10.3390/molecules14041448
Received: 16 March 2009 / Revised: 1 April 2009 / Accepted: 2 April 2009 / Published: 7 April 2009
Cited by 18 | PDF Full-text (112 KB) | HTML Full-text | XML Full-text
Abstract
A Quantitative Structure Activity Relationship (QSAR) study has been an attempted on a series of 88 N-aryl derivatives which display varied inhibitory activity towards both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), targets in Alzheimer’s drug discovery. QSAR models were derived for 53 and
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A Quantitative Structure Activity Relationship (QSAR) study has been an attempted on a series of 88 N-aryl derivatives which display varied inhibitory activity towards both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), targets in Alzheimer’s drug discovery. QSAR models were derived for 53 and 61 compounds for each target, respectively, with the aid of genetic function approximation (GFA) technique using topological, molecular shape, electronic and structural descriptors. The predictive ability of the QSAR model was evaluated using a test set of 26 compounds for AChE (r2pred = 0.857), (q2 = 0.803) and 20 compounds for BChE (r2 pred = 0.882), (q2 = 0.857). The QSAR models point out that AlogP98, Wiener, Kappa-1-AM, Dipole-Mag, and CHI-1 are the important descriptors effectively describing the bioactivity of the compounds. Full article
Open AccessArticle Polyphenolic Profile and Bioactivity Study of Oenothera speciosa Nutt. Aerial Parts
Molecules 2009, 14(4), 1456-1467; doi:10.3390/molecules14041456
Received: 10 February 2009 / Revised: 19 March 2009 / Accepted: 26 March 2009 / Published: 7 April 2009
Cited by 17 | PDF Full-text (194 KB) | HTML Full-text | XML Full-text
Abstract
Two new flavonol glycosides, myricetin 4'-O-α-L-rhamnopyranoside (1) and quercetin 3'-O-α-L-rhamnopyranoside (2), together with a novel biflavonol compound, speciin (3), as well as eleven phenolic metabolites, namely myricitrin (4), europetin 3-O-α-L-1C4-rhamnopyranoside (5), quercitrin (6),
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Two new flavonol glycosides, myricetin 4'-O-α-L-rhamnopyranoside (1) and quercetin 3'-O-α-L-rhamnopyranoside (2), together with a novel biflavonol compound, speciin (3), as well as eleven phenolic metabolites, namely myricitrin (4), europetin 3-O-α-L-1C4-rhamnopyranoside (5), quercitrin (6), hyperin (7), rhamnetin 3-O-β-galacto-pyranoside (8), caffeic acid (9), caffeic acid methyl ester (10), chlorogenic acid (11), chlorogenic acid methyl ester (12), gallic acid (13) and gallic acid methyl ester (14), were identified from the 80 % methanol extract of the aerial parts (leaves and stems) of Oenothera speciosa Nutt. (Onagraceae). In addition myricetin (15), quercetin (16) and ellagic acid (17) were identified from the chloroform extract. The structures were established depending on their chemical and physical analyses (UV, HR-ESIMS, 1D and 2D NMR). It was found that 80 % aqueous methanol extract of O. speciosa is non-toxic to mice up to 5 g kg-1b.wt. The investigated extract exhibited significant antihyperglycaemic and anti-inflammatory activities in a dose dependant manner. Also, the 80 % methanol extract, myricitrin(4) and hyperin(7) showed potent antioxidant activity in vitro using 1,1-diphenyl 2-picryl hydrazyl (DPPH) radical assay. Full article
Open AccessCommunication An Efficient One-Pot Three-Component Synthesis of Fused 1,4-Dihydropyridines Using HY-Zeolit
Molecules 2009, 14(4), 1468-1474; doi:10.3390/molecules14041468
Received: 6 March 2009 / Revised: 19 March 2009 / Accepted: 30 March 2009 / Published: 8 April 2009
Cited by 31 | PDF Full-text (113 KB) | HTML Full-text | XML Full-text
Abstract A facile and convenient protocol was developed for the fast (2.5-3.5 h) and high yielding (70-90 %) synthesis of fused 1,4-dihydropyridines from dimedone in the presence of HY-zeolite as an efficient recyclable heterogeneous catalyst. Full article
Open AccessArticle Maize Arabinoxylan Gels as Protein Delivery Matrices
Molecules 2009, 14(4), 1475-1482; doi:10.3390/molecules14041475
Received: 24 February 2009 / Revised: 13 March 2009 / Accepted: 18 March 2009 / Published: 8 April 2009
Cited by 20 | PDF Full-text (149 KB) | HTML Full-text | XML Full-text
Abstract
The laccase induced gelation of maize bran arabinoxylans at 2.5% (w/v) in the presence of insulin or β-lactoglobulin at 0.1% (w/v) was investigated. Insulin and β-lacto-globulin did not modify either the gel elasticity (9 Pa) or the cross-links content (0.03 and 0.015 mg
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The laccase induced gelation of maize bran arabinoxylans at 2.5% (w/v) in the presence of insulin or β-lactoglobulin at 0.1% (w/v) was investigated. Insulin and β-lacto-globulin did not modify either the gel elasticity (9 Pa) or the cross-links content (0.03 and 0.015 mg di- and triferulic acids/mg arabinoxylan, respectively). The protein release capability of the gel was also investigated. The rate of protein release from gels was dependent on the protein molecular weight. The apparent diffusion coefficient was 0.99 × 10-7 and 0.79 × 10-7 cm2/s for insulin (5 kDa) and β-lactoglobulin (18 kDa), respectively. The results suggest that maize bran arabinoxylan gels can be potential candidates for the controlled release of proteins. Full article
Open AccessArticle Synthesis of Novel Hybrid Molecules from Precursors With Known Antiparasitic Activity
Molecules 2009, 14(4), 1483-1494; doi:10.3390/molecules14041483
Received: 4 March 2009 / Revised: 2 April 2009 / Accepted: 7 April 2009 / Published: 9 April 2009
Cited by 24 | PDF Full-text (157 KB) | HTML Full-text | XML Full-text
Abstract
Three novel new compounds derived from antiparasitic precursors have been synthesized and tested for their antiamoebic and antigiardial activities. The condensation of 2-(2-methyl-5-1H-nitroimidazolyl)ethylamine (6) with 5-nitro-2-furylacrylic acid (7) gave 3-(5-nitrofuran-2-yl)-N-[2-(5-nitroimidazol-1-yl)ethyl]acrylamide (8). Condensation of 7 with 7-chloro-4-(piperazin-1-yl)quinoline (9) afforded 1-[4-(7-chloroquinolin-4-yl)piperazin-1-yl)-3-(5-nitrofuran-2-yl)propenone as a mixture of
[...] Read more.
Three novel new compounds derived from antiparasitic precursors have been synthesized and tested for their antiamoebic and antigiardial activities. The condensation of 2-(2-methyl-5-1H-nitroimidazolyl)ethylamine (6) with 5-nitro-2-furylacrylic acid (7) gave 3-(5-nitrofuran-2-yl)-N-[2-(5-nitroimidazol-1-yl)ethyl]acrylamide (8). Condensation of 7 with 7-chloro-4-(piperazin-1-yl)quinoline (9) afforded 1-[4-(7-chloroquinolin-4-yl)piperazin-1-yl)-3-(5-nitrofuran-2-yl)propenone as a mixture of two isomers; 10-a (the E-isomer) and 10-b (the Z-isomer). In addition, the reaction of 9 with 1-(2-bromoethyl)-2-methyl-5-nitroimidazole (11) in the presence of K2CO3 and NaI yielded 7-chloro-4-(4-[2-(5-nitroimidazol-1-yl)ethyl]-piprazin-1-yl)quinoline (12). On the basis of preliminary screening data for these new compounds, compound 12 exhibited potent lethal activities against Entamoeba histolytica and Giardia intestinalis; its IC50 ( about 1 µM) was lower, at least by a factor of five, compared to the standard drug, metronidazole. In addition, the IC50 of compound 12 against the tested parasites is 600 times below that against Hep-2 and Vero cells. Compounds 8 and 10-a also exhibited potent or moderate antiamoebic and antigiardial activities with IC50 values of about 5.5 µM, and 140 µM, respectively, against the tested parasites. These two hybrid molecules, 8, 10-a, were also non-cytotoxic at the lethal concentrations against the parasites. Full article
Open AccessArticle Synthesis and Molecular Descriptor Characterization of Novel 4-Hydroxy-chromene-2-one Derivatives as Antimicrobial Agents
Molecules 2009, 14(4), 1495-1512; doi:10.3390/molecules14041495
Received: 25 February 2009 / Revised: 26 March 2009 / Accepted: 7 April 2009 / Published: 14 April 2009
Cited by 20 | PDF Full-text (253 KB) | HTML Full-text | XML Full-text
Abstract
Several novel 4-hydroxy-chromene-2-one derivatives 2b-16b were easily prepared through condensation reactions with microwave heating and characterized by elemental analysis, IR, 1H-NMR and mass spectrometry. Geometry optimization of these compounds was executed by PM3, PM5 and Minimize Energy methods to describe them via
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Several novel 4-hydroxy-chromene-2-one derivatives 2b-16b were easily prepared through condensation reactions with microwave heating and characterized by elemental analysis, IR, 1H-NMR and mass spectrometry. Geometry optimization of these compounds was executed by PM3, PM5 and Minimize Energy methods to describe them via molecular descriptors. The antimicrobial activity of the synthesized compounds was evaluated against different microbial strains using two different methods: the diffusion method and the micro-dilution method. All data indicated that the products possess antimicrobial activity which depends on the nature of substituent attached to the benzopyran moiety. In general, after 24 h the MIC values of most tested coumarins was 0.13 mg/mL, but compounds 1 and 6b displayed the strongest antimicrobial activity on the tested cultures of bacteria after 48 h. Compound 13b has the strongest growth inhibitory potential on fungus C. albicans, tested by diffusion method,with an inhibition zone of 30-37 mm at a concentration of 150 µg/mL. The conclusion of this experiment is that the synthesized compounds have varied and different influence on different classes of bacteria and the fungus C. albicans. Full article
(This article belongs to the Special Issue Coumarins and Xanthones)
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Open AccessArticle Comparative Molecular Docking of Antitrypanosomal Natural Products into Multiple Trypanosoma brucei Drug Targets
Molecules 2009, 14(4), 1513-1536; doi:10.3390/molecules14041513
Received: 22 February 2009 / Revised: 7 April 2009 / Accepted: 8 April 2009 / Published: 14 April 2009
Cited by 20 | PDF Full-text (1819 KB) | HTML Full-text | XML Full-text
Abstract
Antitrypanosomal natural products with different structural motifs previously shown to have growth inhibitory activity against Trypanosoma brucei were docked into validated drug targets of the parasite, which include trypanothione reductase, rhodesain, farnesyl diphosphate synthase, and triosephosphate isomerase. The in-silico calculations predicted that lowest
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Antitrypanosomal natural products with different structural motifs previously shown to have growth inhibitory activity against Trypanosoma brucei were docked into validated drug targets of the parasite, which include trypanothione reductase, rhodesain, farnesyl diphosphate synthase, and triosephosphate isomerase. The in-silico calculations predicted that lowest energy docked poses of a number of the compounds can interact with catalysis-dependent residues, thus making them possible catalytic inhibitors and of course physiologically active. Compounds that possess a number of hydrogen-bond-accepting and/or -donating groups like phenolics and quinones show extensive interactions with the targets. Compounds like cissampeloflavone, 3-geranylemodin and ningpogenin thus offer profound promise. Full article
(This article belongs to the Special Issue Neglected Diseases: Medicinal Chemistry and Natural Product Chemistry)
Open AccessArticle Determination of Proton Relaxivities of Mn(II), Cu(II) and Cr(III) added to Solutions of Serum Proteins
Molecules 2009, 14(4), 1537-1545; doi:10.3390/molecules14041537
Received: 26 February 2009 / Revised: 18 March 2009 / Accepted: 10 April 2009 / Published: 14 April 2009
Cited by 10 | PDF Full-text (199 KB) | HTML Full-text | XML Full-text
Abstract
Relaxometric studies are still of scientific interest due to their use in medicine and biology. In this study, proton T1 and T2 relaxivities of Mn(II), Cu(II) and Cr(III) in water were determined in the presence and absence of various proteins (albumin,
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Relaxometric studies are still of scientific interest due to their use in medicine and biology. In this study, proton T1 and T2 relaxivities of Mn(II), Cu(II) and Cr(III) in water were determined in the presence and absence of various proteins (albumin, α-globulin, γ-globulin, lysozyme, fibrinogen). The 1/T1 and 1/T2 in all solutions are linearly proportional to the concentration of the paramagnetic ions. Mn(II) has the great influence to alter relaxations in all protein solutions, while Cu(II) and Cr(III) have a poor influence on the relaxations. In addition, Mn(II) and Cu(II) are bound to each protein, but Cr(III) is not bound to any protein. Full article
Open AccessArticle Pseudo-cyclic Face-to-face Rigid Structure Caused by the Intramolecular Ion Pair Effect
Molecules 2009, 14(4), 1546-1560; doi:10.3390/molecules14041546
Received: 14 March 2009 / Revised: 9 April 2009 / Accepted: 10 April 2009 / Published: 14 April 2009
PDF Full-text (248 KB) | HTML Full-text | XML Full-text
Abstract
Six 3-methylpyridine zwitterions and six quinoline zwitterions were synthesized through the reaction of 4-hydroxycoumarins, p-benzoquinone and the corresponding N-aromatics. The novel pseudo-cyclic face-to-face rigid structure of the zwitterion was elucidated by 1H-NMR at different temperatures, and assumed to be caused
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Six 3-methylpyridine zwitterions and six quinoline zwitterions were synthesized through the reaction of 4-hydroxycoumarins, p-benzoquinone and the corresponding N-aromatics. The novel pseudo-cyclic face-to-face rigid structure of the zwitterion was elucidated by 1H-NMR at different temperatures, and assumed to be caused by both the intramolecular ion pair attraction and the steric interaction. Full article
(This article belongs to the Special Issue Coumarins and Xanthones)
Open AccessArticle Trinor-cycloartane Glycosides from the Rhizomes of Cimicifuga foetida
Molecules 2009, 14(4), 1578-1584; doi:10.3390/molecules14041578
Received: 16 March 2009 / Revised: 2 April 2009 / Accepted: 7 April 2009 / Published: 17 April 2009
Cited by 6 | PDF Full-text (164 KB) | HTML Full-text | XML Full-text
Abstract
Three new trinor-cycloartane glycosides, 15α-hydroxy-16-dehydroxy-16(24)-en-foetidinol-3-O-β-D-xylopyranoside (1), 28-hydroxy-foetidinol-3-O-β-D-xylopyranoside (2) and foetidinol-3-O-β-D-xylopyranosyl-(1”→3’)-β-D-xylopyranoside (3) together with the known compound foetidinol-3-O-β-D-xylopyranoside (4) were isolated from the n-BuOH fraction
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Three new trinor-cycloartane glycosides, 15α-hydroxy-16-dehydroxy-16(24)-en-foetidinol-3-O-β-D-xylopyranoside (1), 28-hydroxy-foetidinol-3-O-β-D-xylopyranoside (2) and foetidinol-3-O-β-D-xylopyranosyl-(1”→3’)-β-D-xylopyranoside (3) together with the known compound foetidinol-3-O-β-D-xylopyranoside (4) were isolated from the n-BuOH fraction of the roots of Cimicifuga foetida. Their structures were elucidated on the basis of spectroscopic and chemical reaction data. Full article
Open AccessArticle Essential Oil Composition of Artemisia herba-alba from Southern Tunisia
Molecules 2009, 14(4), 1585-1594; doi:10.3390/molecules14041585
Received: 19 January 2009 / Revised: 27 February 2009 / Accepted: 9 March 2009 / Published: 20 April 2009
Cited by 31 | PDF Full-text (149 KB) | HTML Full-text | XML Full-text
Abstract
The composition of the essential oil hydrodistilled from the aerial parts of 18 individual Artemisia herba-alba Asso. plants collected in southern Tunisia was determined by GC and GCMS analysis. The oil yield varied between 0.68% v/w and 1.93% v/w. One hundred components were
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The composition of the essential oil hydrodistilled from the aerial parts of 18 individual Artemisia herba-alba Asso. plants collected in southern Tunisia was determined by GC and GCMS analysis. The oil yield varied between 0.68% v/w and 1.93% v/w. One hundred components were identified, 21 of of which are reported for the first time in Artemisia herba-alba oil. The oil contained 10 components with percentages higher than 10%. The main components were cineole, thujones, chrysanthenone, camphor, borneol, chrysanthenyl acetate, sabinyl acetate, davana ethers and davanone. Twelve samples had monoterpenes as major components, three had sesquiterpenes as major components and the last three samples had approximately the same percentage of monoterpenes and sesquiterpenes. The chemical compositions revealed that ten samples had compositions similar to those of other Artemisia herba-alba essential oils analyzed in other countries. The remaining eight samples had an original chemical composition. Full article
Open AccessArticle Synthesis of γ-Nitro Aliphatic Methyl Esters Via Michael Additions Promoted by Microwave Irradiation
Molecules 2009, 14(4), 1595-1604; doi:10.3390/molecules14041595
Received: 5 February 2009 / Revised: 21 March 2009 / Accepted: 8 April 2009 / Published: 21 April 2009
Cited by 9 | PDF Full-text (152 KB) | HTML Full-text | XML Full-text
Abstract A simple and efficient protocol has been developed for the direct synthesis of γ-nitrobutyric acid methyl esters under microwave irradiation. This methodology reduces reaction times from days to minutes, compared to conventional conditions. Additionally, these conditions increased yields and provided cleaner reactions. Full article
(This article belongs to the Special Issue Microwave Assisted Synthesis)
Open AccessArticle Preparation of Benzothiazole-Substituted Carbosilane Dendrimers up to the 7th Generation
Molecules 2009, 14(4), 1605-1613; doi:10.3390/molecules14041605
Received: 18 March 2009 / Revised: 13 April 2009 / Accepted: 20 April 2009 / Published: 21 April 2009
Cited by 4 | PDF Full-text (726 KB) | HTML Full-text | XML Full-text
Abstract
Carbosilane dendrimers with 2-(2-phenyloxy)benzothiazole groups on the periphery were prepared from the 1st to the 7th generation. All dendrimers were characterized by 1H- and 13C-NMR, elemental analysis, MALDI TOF MS, GPC, and PL (photoluminescence) spectroscopy. Characteristic PDI (Polydisperse Index)
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Carbosilane dendrimers with 2-(2-phenyloxy)benzothiazole groups on the periphery were prepared from the 1st to the 7th generation. All dendrimers were characterized by 1H- and 13C-NMR, elemental analysis, MALDI TOF MS, GPC, and PL (photoluminescence) spectroscopy. Characteristic PDI (Polydisperse Index) values of the peaks corresponding to the respective dendrimers in the GPC data is in very narrow range of 1.00~1.04. All PL spectra show a blue-shift increasing with generation from the 1st to the 7th. Full article
Open AccessArticle Spectroscopic Investigations of the Binding Interaction of a New Indanedione Derivative with Human and Bovine Serum Albumins
Molecules 2009, 14(4), 1614-1626; doi:10.3390/molecules14041614
Received: 17 March 2009 / Revised: 15 April 2009 / Accepted: 20 April 2009 / Published: 24 April 2009
Cited by 23 | PDF Full-text (209 KB) | HTML Full-text | XML Full-text
Abstract
Binding of a newly synthesized indanedione derivative, 2-(2-hydroxy-3-ethoxybenzylidene)-1,3-indanedione (HEBID), to human and bovine serum albumins (HSA and BSA), under simulated physiological conditions was monitored by fluorescence spectroscopy. The binding parameters (binding constants and number of binding sites) and quenching constants were determined according
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Binding of a newly synthesized indanedione derivative, 2-(2-hydroxy-3-ethoxybenzylidene)-1,3-indanedione (HEBID), to human and bovine serum albumins (HSA and BSA), under simulated physiological conditions was monitored by fluorescence spectroscopy. The binding parameters (binding constants and number of binding sites) and quenching constants were determined according to literature models. The quenching mechanism was assigned to a Förster non-radiative energy transfer due to the HEBID-SA complex formation. A slightly increased affinity of HEBID for HSA was found, while the number of binding sites is approximately one for both albumins. The molecular distance between donor (albumin) and acceptor (HEBID) and the energy transfer efficiency were estimated, in the view of Förster’s theory. The effect of HEBID on the protein conformation was investigated using circular dichroism and synchronous fluorescence spectroscopies. The results revealed partial unfolding in the albumins upon interaction, as well as changes in the local polarity around the tryptophan residues Full article
Open AccessArticle Protective Effects of Celery Juice in Treatments with Doxorubicin
Molecules 2009, 14(4), 1627-1638; doi:10.3390/molecules14041627
Received: 3 March 2009 / Revised: 14 April 2009 / Accepted: 23 April 2009 / Published: 24 April 2009
Cited by 9 | PDF Full-text (133 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this work was to investigate possible protective effect of celery juice in doxorubicin treatment. The following biochemical parameters were determined: content of reduced glutathione, activities of catalase, xanthine oxidase, glutathione peroxidase, peroxidase, and lipid peroxidation intensity in liver homogenate and
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The aim of this work was to investigate possible protective effect of celery juice in doxorubicin treatment. The following biochemical parameters were determined: content of reduced glutathione, activities of catalase, xanthine oxidase, glutathione peroxidase, peroxidase, and lipid peroxidation intensity in liver homogenate and blood hemolysate. We examined influence of diluted pure celery leaves and roots juices and their combinations with doxorubicine on analyzed biochemical parameters. Celery roots and leaves juices influenced the examined biochemical parameters and showed protective effects when applied with doxorubicine. Full article
Open AccessArticle Comparision of the Cytotoxic Effects of Birch Bark Extract, Betulin and Betulinic Acid Towards Human Gastric Carcinoma and Pancreatic Carcinoma Drug-sensitive and Drug-Resistant Cell Lines
Molecules 2009, 14(4), 1639-1651; doi:10.3390/molecules14041639
Received: 17 March 2009 / Revised: 15 April 2009 / Accepted: 22 April 2009 / Published: 24 April 2009
Cited by 30 | PDF Full-text (262 KB) | HTML Full-text | XML Full-text
Abstract
Betulin and betulinic acid are naturally occurring pentacyclic triterpenes showing cytotoxicity towards a number of cancer cell lines. These compounds can be found in the bark of the many plants. In this report we have compared the cytotoxic activity of crude birch bark
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Betulin and betulinic acid are naturally occurring pentacyclic triterpenes showing cytotoxicity towards a number of cancer cell lines. These compounds can be found in the bark of the many plants. In this report we have compared the cytotoxic activity of crude birch bark extract and purified betulin and betulinic acid towards human gastric carcinoma (EPG85-257) and human pancreatic carcinoma (EPP85-181) drug-sensitive and drug-resistant (daunorubicin and mitoxantrone) cell lines. Our results show significant differences in sensitivity between cell lines depending on the compound used, and suggest that both betulin and betulinic acid can be considered as a promising leads in the treatment of cancer. Full article
(This article belongs to the Special Issue Triterpenes and Triterpenoids)

Review

Jump to: Research

Open AccessReview The Shorter the Better: Reducing Fixed Primer Regions of Oligonucleotide Libraries for Aptamer Selection
Molecules 2009, 14(4), 1353-1369; doi:10.3390/molecules14041353
Received: 20 February 2009 / Revised: 18 March 2009 / Accepted: 25 March 2009 / Published: 27 March 2009
Cited by 17 | PDF Full-text (703 KB) | HTML Full-text | XML Full-text
Abstract
Oligonucleotide aptamers are highly structured DNA or RNA molecules, or modified versions thereof, that can bind to targets with specific affinities comparable to antibodies. They are identified through an in vitro selection process termed SELEX (Systematic Evolution of Ligands by EXponential enrichment) to
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Oligonucleotide aptamers are highly structured DNA or RNA molecules, or modified versions thereof, that can bind to targets with specific affinities comparable to antibodies. They are identified through an in vitro selection process termed SELEX (Systematic Evolution of Ligands by EXponential enrichment) to recognize a wide variety of targets, from small molecules to proteins, and from cultured cells to whole organisms. Aptamers possess a number of desirable properties, such as ease of synthesis, stability, robustness, and lack of immunogenicity. Standard SELEX libraries require two primers, one on each side of a central random domain, to amplify the target-bound sequences via PCR or RT-PCR. However, these primer sequences cause non-specific binding by their nature, and have been reported to lead to large numbers of false-positive binding sequences, or to interfere with binding of sequences within the random regions. This review is focused on methods which have been developed to eliminate fixed primer interference during the SELEX process. Full article
(This article belongs to the Special Issue Nucleic Acids)
Open AccessReview Temozolomide with Radiation Therapy in High Grade Brain Gliomas: Pharmaceuticals Considerations and Efficacy;A Review Article
Molecules 2009, 14(4), 1561-1577; doi:10.3390/molecules14041561
Received: 12 March 2009 / Revised: 10 April 2009 / Accepted: 15 April 2009 / Published: 16 April 2009
Cited by 21 | PDF Full-text (263 KB) | HTML Full-text | XML Full-text
Abstract
Malignant gliomas (glioblastoma multiforme and anaplastic astrocytoma) which have a combined incidence of 5–8/100,000 population, represent the most common primary central nervous system tumors. The treatment outcomes even with aggressive approach including surgery, radiaton therapy and chemotherapy are dismal with median reported survival
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Malignant gliomas (glioblastoma multiforme and anaplastic astrocytoma) which have a combined incidence of 5–8/100,000 population, represent the most common primary central nervous system tumors. The treatment outcomes even with aggressive approach including surgery, radiaton therapy and chemotherapy are dismal with median reported survival is less than 1 year. Temozolomide is a new drug which has shown promise in treating malignant gliomas and other difficult-to-treat tumors. This drug is a per os (p.o) imidazotetrazine second-generation alkylating agent which represents the leading compound in a new class of chemotherapeutic agents that enter the cerebrospinal fluid and do not require hepatic metabolism for activation. The efficacy of temozolomide was tested in vitrostudies and has demonstrated schedule-dependent antitumor activity against highly resistant malignancies, including high-grade glioma (HGG). In addition, in clinical studies, temozolomide consistently demonstrates reproducible linear pharmacokinetics with approximately 100% p.o. bioavailability, noncumulative minimal myelosuppression that is rapidly reversible, and activity against a variety of solid tumors in both children and adults. Moreover, preclinical studies have evaluated the combination of temozolomide with other alkylating agents and inhibitors of the DNA repair protein O6-alkylguanine alkyltransferase to overcome resistance to chemotherapy in malignant glioma and malignant metastatic melanoma. At the present time temozolomide is approved in the United States for the treatment of adult patients with refractory anaplastic astrocytoma and, in the European Union, for treatment of glioblastoma multiforme showing progression or recurrence after standard therapy. Temozolomide’s characteristics which make it a candidate for a wide range of clinical testing to evaluate the potential of combination treatments in different tumor types are its predictable bioavailability and minimal toxicity. An overview of the mechanism of action of temozolomide and a summary of results from more important randomized controlled clinical trials in high grade gliomas are presented here. Full article

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