Molecules

134 KiB

Open AccessArticle

Effects of Different Carriers on the Production of Isoflavone Powder from Soybean Cake

by Tsai-Hua Kao and Bing-Huei Chen

Molecules 2007, 12(4), 917-931; https://doi.org/10.3390/12040917 - 30 Apr 2007

Cited by 14 | Viewed by 11644

The objectives of this study were to use soybean cake as the raw material for the production of isoflavone powder and compare the effects of different carriers as well as drying methods on the powder quality. Results showed that with spray drying, a [...] Read more.

The objectives of this study were to use soybean cake as the raw material for the production of isoflavone powder and compare the effects of different carriers as well as drying methods on the powder quality. Results showed that with spray drying, a level of 40 % maltodextrin as carrier produced the highest yield (mass) of isoflavone powder, followed by 10 % gelatin and 1 % sodium alginate. However, a reversed trend was observed for the isoflavone content. With 1 % sodium alginate, freeze drying generated the greatest yield of isoflavone powder, followed by vacuum drying and spray drying. The isoflavone content also exhibited the same tendency. With poly-g-glutamicacid (g-PGA) as carrier, all six levels studied (0.57, 0.28, 0.14, 0.028, 0.014 and 0.003 %) were capable of forming powder containing high amounts of total isoflavone, which was comparable to that using 1% sodiumalginate by freeze drying. Both high- and low-molecular-weight g-PGA showed similar effects in terms of powder yield and isoflavone content. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

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254 KiB

Open AccessArticle

Determination of the Three-dimensional Structure of Gynoside A in Solution using NMR and Molecular Modeling

by Qian Li, Zhi-Hong Yao, Yan-Hong Shi, Xin Liu, Xin-Sheng Yao and Wen-Cai Ye

Molecules 2007, 12(4), 907-916; https://doi.org/10.3390/12040907 - 30 Apr 2007

Cited by 3 | Viewed by 9781

Abstract

The three-dimensional structure of Gynoside A, an ocotillone-type triterpenoid glycoside isolated from Gynostemma pentaphyllum, was determined in pyridine-d₅ and DMSO-d₆ solution through constrained molecular modeling using constraints derived from proton NMR spectra. The calculation yielded well-defined global minima. [...] Read more.

The three-dimensional structure of Gynoside A, an ocotillone-type triterpenoid glycoside isolated from Gynostemma pentaphyllum, was determined in pyridine-d₅ and DMSO-d₆ solution through constrained molecular modeling using constraints derived from proton NMR spectra. The calculation yielded well-defined global minima. Except for some quantitative details the overall structure of Gynoside A in pyridine-d₅ shared many common features with that in DMSO-d₆. The structure in pyridine-d₅ had lower energies than that in DMSO-d₆ solution. Full article

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59 KiB

Open AccessArticle

4'-Acetamidochalcone Derivatives as Potential Antinociceptive Agents

by Fátima De Campos-Buzzi, Pâmela Padaratz, Aleandra Vergilina Meira, Rogério Corrêa, Ricardo José Nunes and Valdir Cechinel-Filho

Molecules 2007, 12(4), 896-906; https://doi.org/10.3390/12040896 - 30 Apr 2007

Cited by 34 | Viewed by 8630

Abstract

Nine acetamidochalcones were synthesized and evaluated as antinociceptive agents using the mice writhing test. Given intraperitoneally all the compounds were more effective than the two reference analgesic drugs (acetylsalicylic acid and acetaminophen) used for comparison. N-{4-[(2E)-3-(4-nitrophenyl)prop-2-enoyl]phenyl}acetamide (6) was the most [...] Read more.

Nine acetamidochalcones were synthesized and evaluated as antinociceptive agents using the mice writhing test. Given intraperitoneally all the compounds were more effective than the two reference analgesic drugs (acetylsalicylic acid and acetaminophen) used for comparison. N-{4-[(2E)-3-(4-nitrophenyl)prop-2-enoyl]phenyl}acetamide (6) was the most effective compound and was therefore selected for more detailed studies. It caused dose-related inhibition in the writhing test, being about 32 to 34-fold more potent than the standard drugs. It was also effective in the second phase of the formalin test and the capsaicin test. These acetamidochalcones, especially compound 6, might be further used as models to obtain new and more potent analgesic drugs. Full article

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143 KiB

Open AccessArticle

Synthesis and Activity of a New Series of(Z)-3-Phenyl-2-benzoylpropenoic Acid Derivatives as Aldose Reductase Inhibitors

by Shao-Jie Wang, Ju-Fang Yan, Dong Hao, Xin-Wen Niu and Mao-Sheng Cheng

Molecules 2007, 12(4), 885-895; https://doi.org/10.3390/12040885 - 30 Apr 2007

Cited by 13 | Viewed by 9908

Abstract

During the course of studies directed towards the discovery of novel aldose reductase inhibitors for the treatment of diabetic complications, we synthesized a series of new (Z)-3-phenyl-2-benzoylpropenoic acid derivatives and tested their in vitro inhibitory activities on rat lens aldose reductase. [...] Read more.

During the course of studies directed towards the discovery of novel aldose reductase inhibitors for the treatment of diabetic complications, we synthesized a series of new (Z)-3-phenyl-2-benzoylpropenoic acid derivatives and tested their in vitro inhibitory activities on rat lens aldose reductase. Of these compounds, (Z)-3-(3,4-dihydroxyphenyl)-2-(4-methylbenzoyl)propenoicacid(3k) was identified as the most potent inhibitor, with an IC₅₀ of 0.49μM. The theoretical binding mode of 3k was obtained by simulation of its docking into the active site of the human aldose reductase crystal structure. Full article

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58 KiB

Open AccessCommunication

How Many Drugs Are Catecholics

by Da-Peng Yang, Hong-Fang Ji, Guang-Yan Tang, Wei Ren and Hong-Yu Zhang

Molecules 2007, 12(4), 878-884; https://doi.org/10.3390/12040878 - 30 Apr 2007

Cited by 49 | Viewed by 20433

Abstract

By examination of the 8659 drugs recorded in the Comprehensive Medicinal Chemistry (CMC) database, 78 catecholics (including five pyrogallolics) were identified, of which 17 are currently prescribed by FDA. Through analyzing the substitutent patterns, ClogPs and O-H bond dissociation enthalpies(BDEs) of [...] Read more.

By examination of the 8659 drugs recorded in the Comprehensive Medicinal Chemistry (CMC) database, 78 catecholics (including five pyrogallolics) were identified, of which 17 are currently prescribed by FDA. Through analyzing the substitutent patterns, ClogPs and O-H bond dissociation enthalpies(BDEs) of the catecholic drugs, some molecular features that may benefit circumventing the toxicity of catecholics were revealed: i) strong electron-donating substituents are excluded; ii) ClogP 3; iii) an energy penalty exists for quinone formation. Besides, the present analyses also suggest that the clinical usage and dosage of currently prescribed catecholic drugs are of importance in designing or screening catecholic antioxidants. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

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94 KiB

Open AccessArticle

Microwave-Assisted Isolation of Essential oil of Cinnamomum iners Reinw. ex Bl.: Comparison with Conventional Hydrodistillation

by Weerachai Phutdhawong, Rungthip Kawaree, Samart Sanjaiya, Waya Sengpracha and Duang Buddhasukh

Molecules 2007, 12(4), 868-877; https://doi.org/10.3390/12040868 - 30 Apr 2007

Cited by 50 | Viewed by 10229

Abstract

Microwave-assistedhydrodistillation was used to isolate an essential oil from the leaves of Cinnamomuminers Reinw. ex Bl., and the results compared with those obtained by conventional hydrodistillation. The composition of the oil from both methods was found to be similar, and (-)-linalool was found [...] Read more.

Microwave-assistedhydrodistillation was used to isolate an essential oil from the leaves of Cinnamomuminers Reinw. ex Bl., and the results compared with those obtained by conventional hydrodistillation. The composition of the oil from both methods was found to be similar, and (-)-linalool was found as the main component (30-50 %). The antioxidant activity of the essential oil obtained by both methods was evaluated using DPPH, ABTS, FRAP and lipid peroxidation methods, all of which indicated the same but insignificant activity. Full article

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70 KiB

Open AccessCommunication

C(aryl)-O Bond Formation from Aryl Methanesulfonates via Consecutive Deprotection and S_NAr Reactions with Aryl Halides in an Ionic Liquid

by Hui Xu and Yang Chen

Molecules 2007, 12(4), 861-867; https://doi.org/10.3390/12040861 - 30 Apr 2007

Cited by 7 | Viewed by 9535

Abstract

An efficient K₃PO₄-mediated synthesis of unsymmetrical diaryl ethers using the ionic liquid [Bmim]BF₄ (1-butyl-3-methylimidazolium tetrafluoroborate) as solvent has been developed. The procedure involves consecutive deprotection of aryl methane-sulfonates and a nucleophilic aromatic substitution (S_NAr) with activated aryl halides. Full article

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232 KiB

Open AccessArticle

Molecular Complexes Based on Tetrathiafulvalene and Dialkylviologens

by Bilkish Rahman, Hiroki Akutsu, Jun-ichi Yamada and Shin’ichi Nakatsuji

Molecules 2007, 12(4), 853-860; https://doi.org/10.3390/12040853 - 27 Apr 2007

Cited by 5 | Viewed by 7709

Abstract

Three kinds of molecular complexes based on tetrathiafulvalene (TTF) and dialkylviologens were prepared and their crystal structures elucidated. While TTF-dimethylviologen complex forms a mixed stack arrangement of donors and acceptors in its crystal structure, TTF donors aggregate with long alkyl groups by CH/p [...] Read more.

Three kinds of molecular complexes based on tetrathiafulvalene (TTF) and dialkylviologens were prepared and their crystal structures elucidated. While TTF-dimethylviologen complex forms a mixed stack arrangement of donors and acceptors in its crystal structure, TTF donors aggregate with long alkyl groups by CH/p and/or van der Waals interactions in a couple of TTF-heptylviologen complexes. Full article

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137 KiB

Open AccessArticle

Identificationof Major Phenolic Compounds of Chinese Water Chestnut and their Antioxidant Activity

by Yanli You, Xuewu Duan, Xiaoyi Wei, Xinguo Su, Mouming Zhao, Jian Sun, Neungnapa Ruenroengklin and Yueming Jiang

Molecules 2007, 12(4), 842-852; https://doi.org/10.3390/12040842 - 25 Apr 2007

Cited by 50 | Viewed by 20392

Abstract

Chinese water chestnut (CWC) is one of the most popular foods among Asian people due to its special taste and medical function. Experiments were conducted to test the antioxidant activity and then determine the major phenolic compound components present in CWC. CWC phenolic [...] Read more.

Chinese water chestnut (CWC) is one of the most popular foods among Asian people due to its special taste and medical function. Experiments were conducted to test the antioxidant activity and then determine the major phenolic compound components present in CWC. CWC phenolic extract strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against α,α-diphenyl-β-picrylhydrazyl (DPPH) radicals, superoxide anions and hydroxyl radicals, which was superior to ascorbic acid and butylated hydroxytoluene (BHT), two commercial used antioxidants. Furthermore, the CWC extract was found to have a relatively higher reducing power, compared with BHT. The major phenolic compounds present in CWC tissues were extracted, purified and identified by high-performance liquid chromatograph (HPLC) as (–)-gallocatechin gallate, (–)-epicatechin gallate and (+)-catechin gallate. This study suggests that CWC tissues exhibit great potential for antioxidant activity and may be useful for their nutritional and medicinal functions. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

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103 KiB

Open AccessArticle

Cytotoxic Triterpenoid Saponins from the Roots of Platycodon grandiflorum

by Lin Zhang, Zhen-Huan Liu and Jing-Kui Tian

Molecules 2007, 12(4), 832-841; https://doi.org/10.3390/12040832 - 23 Apr 2007

Cited by 21 | Viewed by 11802

Abstract

Bioguided fractionation of the ethanol extracts obtained from Platycodon grandiflorum roots led to isolation of two new triterpenoid saponins, characterized as 3-O-β-D-glucopyranosyl-2β,12α,16α,23,24-pentahydroxyoleanane-28(13)-lactone (1) and 3-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-2β,12α,16α,23α-tetrahydroxyoleanane-28(13)- lactone (2) by 1D- and 2D-NMR and MS techniques, as well as chemical means. Both compounds showed cytotoxic [...] Read more.

Bioguided fractionation of the ethanol extracts obtained from Platycodon grandiflorum roots led to isolation of two new triterpenoid saponins, characterized as 3-O-β-D-glucopyranosyl-2β,12α,16α,23,24-pentahydroxyoleanane-28(13)-lactone (1) and 3-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-2β,12α,16α,23α-tetrahydroxyoleanane-28(13)- lactone (2) by 1D- and 2D-NMR and MS techniques, as well as chemical means. Both compounds showed cytotoxic activity against human ECA-109 cells. Full article

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382 KiB

Open AccessArticle

Different Supramolecular Coordination Polymers of [N,N'-di(pyrazin-2-yl)-pyridine-2,6-diamine]Ni(II) with Anions and Solvent Molecules as a Result of Hydrogen Bonding

by Gene-Hsiang Lee and Hsin-Ta Wang

Molecules 2007, 12(4), 821-831; https://doi.org/10.3390/12040821 - 23 Apr 2007

Cited by 3 | Viewed by 8894

Abstract

Ni(II) complexes of N,N'–di(pyrazin–2–yl)pyridine–2,6–diamine (H₂dpzpda) with different anions were synthesized and their structures were determined by X-ray diffraction. Hydrogen bonds between the amino groups and anions assembled the mononuclear molecules into different architectures. The perchlorate complex had a 1-D chain [...] Read more.

Ni(II) complexes of N,N'–di(pyrazin–2–yl)pyridine–2,6–diamine (H₂dpzpda) with different anions were synthesized and their structures were determined by X-ray diffraction. Hydrogen bonds between the amino groups and anions assembled the mononuclear molecules into different architectures. The perchlorate complex had a 1-D chain structure, whereas switching the anion from perchlorate to nitrate resulted in a corresponding change of the supramolecular structure from 1-D to 3-D. When the nitrate complex packed with the co-crystallized water, a double chain structure was formed through hydrogen bonding. The magnetic studies revealed values of g = 2.14 and D = 3.11 cm^-1 for [Ni(H₂dpzpda)₂](ClO₄)₂ (1) and g = 2.18 and D = 2.19 cm^-1 for [Ni(H₂dpzpda)₂](NO₃)₂ (2), respectively. Full article

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44 KiB

Open AccessCommunication

Bis(4-hydroxybenzyl)sulfide: a Sulfur Compound Inhibitor of Histone Deacetylase Isolated from Root Extract of Pleuropterus ciliinervis

by Il Hong Son, Sung Ik Lee, Hyun Duk Yang and Hyung-In Moon

Molecules 2007, 12(4), 815-820; https://doi.org/10.3390/12040815 - 20 Apr 2007

Cited by 13 | Viewed by 8678

Abstract

A sulfur compound, bis(4-hydroxybenzyl)sulfide (1) was isolated from the root extract of Pleuropterus ciliinervis. Its structure was elucidated using NMR spectroscopic techniques and mass spectrometric analysis. Compound 1 showed potent inhibitory activity in a histone deacetylase (HDAC) enzyme assay. It also exhibited [...] Read more.

A sulfur compound, bis(4-hydroxybenzyl)sulfide (1) was isolated from the root extract of Pleuropterus ciliinervis. Its structure was elucidated using NMR spectroscopic techniques and mass spectrometric analysis. Compound 1 showed potent inhibitory activity in a histone deacetylase (HDAC) enzyme assay. It also exhibited growth inhibitory activity on five human tumor cell lines and more sensitive inhibitory activity on the MDA-MB-231 breast tumor cell line. Full article

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69 KiB

Open AccessArticle

Molecularly Imprinted Polymers for 5-Fluorouracil Release in Biological Fluids

by Francesco Puoci, Francesca Iemma, Giuseppe Cirillo, Nevio Picci, Pietro Matricardi and Franco Alhaique

Molecules 2007, 12(4), 805-814; https://doi.org/10.3390/12040805 - 18 Apr 2007

Cited by 74 | Viewed by 14131

Abstract

The aim of this work was to investigate the possibility of employing Molecularly Imprinted Polymers (MIPs) as a controlled release device for 5-fluorouracil (5-FU) in biological fluids, especially gastrointestinal ones, compared to Non Imprinted Polymers (NIPs). MIPs were synthesized using methacrylic acid (MAA) [...] Read more.

The aim of this work was to investigate the possibility of employing Molecularly Imprinted Polymers (MIPs) as a controlled release device for 5-fluorouracil (5-FU) in biological fluids, especially gastrointestinal ones, compared to Non Imprinted Polymers (NIPs). MIPs were synthesized using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as crosslinking agent. The capacity of the polymer to recognize and to bind the template selectively in both organic and aqueous media was evaluated. An in vitro release study was performed both in gastrointestinal and in plasma simulating fluids. The imprinted polymers bound much more 5-Fu than the corresponding non-imprinted ones and showed a controlled/sustained drug release, with MIPs release rate being indeed much more sustained than that obtained from NIPs. These polymers represent a potential valid system for drug delivery and this study indicates that the selective binding characteristic of molecularly imprinted polymers is promising for the preparation of novel controlled release drug dosage form. Full article

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66 KiB

Open AccessArticle

Synthesis of α,β-Unsaturated Ketones as Chalcone Analogues via a S_RN1 Mechanism

by Christophe Curti, Armand Gellis and Patrice Vanelle

Molecules 2007, 12(4), 797-804; https://doi.org/10.3390/12040797 - 18 Apr 2007

Cited by 3 | Viewed by 14565

Abstract

An electron-transfer chain reaction between 2-nitropropane anion and α-bromoketones derived from nitrobenzene and nitrothiophene was demonstrated by mechanistic study and a specific convenient synthetic protocol. Thus, 2-bromo-1-(5-nitrothiophen-2-yl)ethanone or 2-bromo-1-(4-nitrophenyl)ethanone were reacted with several cyclic nitronate anions to form α,β-unsaturated ketones via a S [...] Read more.

An electron-transfer chain reaction between 2-nitropropane anion and α-bromoketones derived from nitrobenzene and nitrothiophene was demonstrated by mechanistic study and a specific convenient synthetic protocol. Thus, 2-bromo-1-(5-nitrothiophen-2-yl)ethanone or 2-bromo-1-(4-nitrophenyl)ethanone were reacted with several cyclic nitronate anions to form α,β-unsaturated ketones via a S_RN1 mechanism. This new method can be used to synthesize a wide variety of chalcone analogues. Full article

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204 KiB

Open AccessArticle

Complexes of 3dⁿ Metal Ions with Thiosemicarbazones: Synthesis and Antimicrobial Activity

by Tudor Rosu, Aurelian Gulea, Anca Nicolae and Rodica Georgescu

Molecules 2007, 12(4), 782-796; https://doi.org/10.3390/12040782 - 17 Apr 2007

Cited by 57 | Viewed by 10800

Abstract

The chelating behavior of the thiosemicarbazone derivatives of 2-hydroxy-8-R-tricyclo[7.3.1.0.^2,7]tridecane-13-one (where R = H, CH₃, C₆H₅) towards Co(II), Ni(II) and Cu(II) has been investigated by elemental analysis, molar conductivity measurements, UV-VIS, IR, ESR spectroscopy and thermal [...] Read more.

The chelating behavior of the thiosemicarbazone derivatives of 2-hydroxy-8-R-tricyclo[7.3.1.0.^2,7]tridecane-13-one (where R = H, CH₃, C₆H₅) towards Co(II), Ni(II) and Cu(II) has been investigated by elemental analysis, molar conductivity measurements, UV-VIS, IR, ESR spectroscopy and thermal studies. It was deduced from the experiments performed that the ligands coordinate to metal ions in different ways – neutral bidentate or mononegative bidentate – depending on the nature of R. Also, if metal acetates are used instead of metal chlorides, the ligands coordinate in a mononegative bidentate fashion, regardless of the nature of R or the thiosemicarbazone type ligand. The antimicrobial activity of the ligands and of the complexes towards samples of Acinetobacter boumanii, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa was determined. Full article

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106 KiB

Open AccessArticle

Chemical Composition and Antimicrobial Activity of the Essential Oil of Algerian Phlomis bovei De Noé subsp. bovei

by Christos Liolios, Hocine Laouer, Nacira Boulaacheb, Olga Gortzi and Ioanna Chinou

Molecules 2007, 12(4), 772-781; https://doi.org/10.3390/12040772 - 12 Apr 2007

Cited by 42 | Viewed by 9180

Abstract

The chemical composition of essential oil obtained by steam distillation of dried aerial parts of Phlomis bovei De Noé subsp. bovei collected from Algeria, was analyzed by GC and GC/MS. Seventy five constituents (corresponding to 86.37% of the total weight) were identified. The [...] Read more.

The chemical composition of essential oil obtained by steam distillation of dried aerial parts of Phlomis bovei De Noé subsp. bovei collected from Algeria, was analyzed by GC and GC/MS. Seventy five constituents (corresponding to 86.37% of the total weight) were identified. The main components were: germacrene D, β-caryophyllene, β-bournonene, thymol and hexahydrofarnesyl acetone. Furthermore, the antimicrobial activity of the oil was evaluated against six Gram (+/-) bacteria and three pathogenic fungi, using the agar dilution technique. It was found that the oil exhibited strong antimicrobial activity against most of the tested microorganisms. Full article

97 KiB

Open AccessArticle

Evaluation of the Antioxidant Properties of Litchi Fruit Phenolics in Relation to Pericarp Browning Prevention

by Xuewu Duan, Genfu Wu and Yueming Jiang

Molecules 2007, 12(4), 759-771; https://doi.org/10.3390/12040759 - 11 Apr 2007

Cited by 139 | Viewed by 17882

Abstract

Phenolics were extracted from litchi fruit pericarp (LFP) tissues, purified and their antioxidant properties analyzed. LFP phenolics strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against α,α-diphenyl-β-picrylhydrazyl (DPPH·) and hydroxyl radicals and superoxide anions. The degradation of deoxyribose by [...] Read more.

Phenolics were extracted from litchi fruit pericarp (LFP) tissues, purified and their antioxidant properties analyzed. LFP phenolics strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against α,α-diphenyl-β-picrylhydrazyl (DPPH·) and hydroxyl radicals and superoxide anions. The degradation of deoxyribose by hydroxyl radicals was inhibited by phenolics acting mainly as iron ion chelators, rather than by directly scavenging the radicals. Phenolics from litchi fruit pericarp were found to display similar reducing power activity as ascorbic acid. The effect of phenolic compound treatment on pericarp browning and electrolyte leakage of litchi fruit was also evaluated and it was observed that application of exogenous litchi phenolics to harvested litchi fruit significantly prevented pericarp browning and delayed increases in electrolyte leakage. These results suggest that litchi pericarp tissue phenolics could be beneficial in scavenging free radicals, maintaining membrane integrity and, thereby inhibiting pericarp browning of litchi fruit. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

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106 KiB

Open AccessReview

Litchi Flavonoids: Isolation, Identification and Biological Activity

by Jiangrong Li and Yueming Jiang

Molecules 2007, 12(4), 745-758; https://doi.org/10.3390/12040745 - 11 Apr 2007

Cited by 100 | Viewed by 18789

Abstract

The current status of the isolation, identification, biological activity, utilization and development prospects of flavonoids found in litchi fruit pericarp (LFP) tissues is reviewed. LFP tissues account for approximately 15% by weight of the whole fresh fruit and are comprised of significant amount [...] Read more.

The current status of the isolation, identification, biological activity, utilization and development prospects of flavonoids found in litchi fruit pericarp (LFP) tissues is reviewed. LFP tissues account for approximately 15% by weight of the whole fresh fruit and are comprised of significant amount of flavonoids. The major flavonoids in ripe LFP include flavonols and anthocyanins. The major flavanols in the LFP are reported to be procyanidin B4, procyanidin B2 and epicatechin, while cyanindin-3-rutinside, cyanidin-3-glucoside, quercetin-3-rutinosde and quercetin-3-glucoside are identified as the important anthocyanins. Litchi flavanols and anthocyanins exhibit good potential antioxidant activity. The hydroxyl radical and superoxide anion scavenging activities of procyanidin B2 are greater than those of procyanidin B4 and epicatechin, while epicatechin has the highest α,α-diphenyl-β-picrylhydrazyl radical (DPPH·) scavenging activity. In addition to the antioxidant activity, LFP extract displays a dose- and time-dependent inhibitory effect on human breast cancer, which could be attributed, in part, to its inhibition of proliferation and induction of apoptosis in cancer cells through upregulation and down-regulation of multiple genes. Furthermore, various anticancer activities are observed for epicatechin, procyanidin B2, procyanidin B4 and the ethyl acetate fraction of LFP tissue extracts. Procyanidin B4 and the ethyl acetate fraction show a stronger inhibitory effect on HELF than MCF-7 proliferation, while epicatechin and procyanidin B2 have lower cytotoxicities towards MCF-7 and HELF than paclitaxel. It is therefore suggested that flavonoids from LFP might be potentially useful components for functional foods and/or anti-breast cancer drugs. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

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98 KiB

Open AccessArticle

Synthesis of (R)-Dihydropyridones as Key Intermediates for an Efficient Access to Piperidine Alkaloids

by Evangelia N Tzanetou, Konstantinos M Kasiotis, Prokopios Magiatis and Serkos A Haroutounian

Molecules 2007, 12(4), 735-744; https://doi.org/10.3390/12040735 - 10 Apr 2007

Cited by 19 | Viewed by 9095

Abstract

The efficient transformation of D-glucal to (2R)-hydroxymethyldihydro-pyridinone 5 in seven steps and 35 % overall yield is reported. Dihydropyridone 5 constitutes a versatile chiral building block for the synthesis of various piperidine alkaloids. In this regard, 5 was converted to [...] Read more.

The efficient transformation of D-glucal to (2R)-hydroxymethyldihydro-pyridinone 5 in seven steps and 35 % overall yield is reported. Dihydropyridone 5 constitutes a versatile chiral building block for the synthesis of various piperidine alkaloids. In this regard, 5 was converted to piperidinol 13 and piperidinone 15, that may be further elaborated for the syntheses of (+)-desoxoprosophylline (1) and deoxymannojirimycin (3) or D-mannolactam (4), respectively. Full article

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129 KiB

Open AccessArticle

Multi-step Redox Systems with NIR-Fluorescence Based on 4H-Imidazoles

by Martin Matschke and Rainer Beckert

Molecules 2007, 12(4), 723-734; https://doi.org/10.3390/12040723 - 5 Apr 2007

Cited by 14 | Viewed by 11608

Abstract

A new class of 4H-imidazoles was synthesized starting from fused-ring aromatic dinitriles. Strong bathochromic shifts of the longest wavelength absorptions were observed in the corresponding UV/vis spectra due to a conversion of the merocyanine chromophores into cyanines/(aza)oxonoles upon protonation/deprotonation of the [...] Read more.

A new class of 4H-imidazoles was synthesized starting from fused-ring aromatic dinitriles. Strong bathochromic shifts of the longest wavelength absorptions were observed in the corresponding UV/vis spectra due to a conversion of the merocyanine chromophores into cyanines/(aza)oxonoles upon protonation/deprotonation of the 4H-imidazoles. Novel boratetraazapentalenes were synthesized via a cyclization reaction with boron trifluoride. These mesoionic species bearing a cyanine chromophore not only show NIR-fluorescence, they also participate as part of a quasi-reversible multi-step redox system. Large calculated semiquinone formation constants K_SEM (3x10¹⁰ to 5x10¹¹) indicate a high thermodynamic stability of the corresponding radical anions (SEM). Full article

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146 KiB

Open AccessArticle

Synthesis and X-ray Structure of the Inclusion Complex of Dodecamethylcucurbit[6]uril with 1,4-Dihydroxybenzene

by Li-Bin Lu, Yun-Qian Zhang, Qian-Jiang Zhu, Sai-Feng Xue and Zhu Tao

Molecules 2007, 12(4), 716-722; https://doi.org/10.3390/12040716 - 5 Apr 2007

Cited by 26 | Viewed by 11197

Abstract

The synthesis, and X-ray crystal structure of the inclusion host-guest complex of dodecamethylcucurbit[6]uril (DDMeQ[6]) with 1,4-dihydroxybenzene (DHOBEN) are reported. The complex crystallizes in the space group P21/c (No.14) with a =12.2847(4), b = 12.6895(4), c = 15.1310(4) Å, α = 74.6960(10), β = [...] Read more.

The synthesis, and X-ray crystal structure of the inclusion host-guest complex of dodecamethylcucurbit[6]uril (DDMeQ[6]) with 1,4-dihydroxybenzene (DHOBEN) are reported. The complex crystallizes in the space group P21/c (No.14) with a =12.2847(4), b = 12.6895(4), c = 15.1310(4) Å, α = 74.6960(10), β = 71.4090(10), γ = 86.5090(10)° and Z = 1. A novel approach to dodecamethylcucurbit[6]uril synthesis is also described. To separate dodecamethylcucurbit[6]uril, 1,4-dihydroxybenzene is used as a guest molecule for crystallization of the fully methyl-substituted cucurbituril. The driving force for the self-assembled inclusion host-guest complex can be attributed to not only the cavity interaction of dodecamethylcucurbit[6]uril (host), but also to the hydrogen bonding between the carbonyl oxygen at the portals of the host and the hydroxy groups of the guest. Full article

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Open AccessArticle

Investigation on the Binding of Polycyclic AromaticHydrocarbons with Soil Organic Matter: A Theoretical Approach

by Patchreenart Saparpakorn, Jae Hyoun Kim and Supa Hannongbua

Molecules 2007, 12(4), 703-715; https://doi.org/10.3390/12040703 - 5 Apr 2007

Cited by 28 | Viewed by 11848

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants of the terrestrial environment that have been designated as Environmental Protection Agency (EPA) Priority Pollutants. In this study, molecular modeling was used to examine the physical and chemical characteristics of soil organic matter (SOM), fulvic acid [...] Read more.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants of the terrestrial environment that have been designated as Environmental Protection Agency (EPA) Priority Pollutants. In this study, molecular modeling was used to examine the physical and chemical characteristics of soil organic matter (SOM), fulvic acid (FA) and humic acid (HA), as well as their binding interactions with PAHs. The molecular structures of 18 PAHs were built by using the SYBYL 7.0 program and then fully optimized by a semiempirical (AM1) method. A molecular docking program, AutoDock 3.05, was used to calculate the binding interactions between the PAHs, and three molecular structure models including FA (Buffle’s model), HA (Stevenson’s model) and SOM (Schulten and Schnitzer’s model). The π-π interactions and H-bonding interactions were found to play an important role in the intermolecular bonding of the SOM/PAHs complexes. In addition, significant correlations between two chemical properties, boiling point (bp) and octanol/water partition coefficient (Log Kow) and final docking energies were observed. The preliminary docking results provided knowledge of the important binding modes to FA, HA and SOM, and thereby to predict the sorption behavior of PAHs and other pollutants. Full article

(This article belongs to the Special Issue Heterocycles)

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Molecules, Volume 12, Issue 4 (April 2007) – 22 articles , Pages 703-931

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