- Biotransformation of resveratrol: Synthesis of trans-dehydrodimers catalyzed by laccases from Myceliophtora thermophyla and from Trametes pubescens
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Laccases from different sources have been used, for the first time, for the selective oxidation of the stilbenic phytoalexin trans-resveratrol (3,5,4′-trihydroxystilbene, 1a) on a preparative scale. Specifically, the enzymes from Myceliophtora thermophyla
- Nicotra, Silvia,Cramarossa, Maria Rita,Mucci, Adele,Pagnoni, Ugo Maria,Riva, Sergio,Forti, Luca
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- δ-viniferin, a resveratrol dehydrodimer: One of the major stilbenes synthesized by stressed grapevine leaves
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δ-Viniferin is a resveratrol dehydrodimer, an isomer of ε-viniferin. This compound has been reported as a molecule produced in vitro by the oxidative dimerization of resveratrol by plant peroxidases or fungal laccases. It was also recently identified in w
- Pezet, Roger,Perret, Camille,Jean-Denis, Julien Bernard,Tabacchi, Raffaele,Gindro, Katia,Viret, Olivier
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- HPLC Analysis of Grapevine Phytoalexins Coupling Photodiode Array Detection and Fluorometry
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A reversed-phase HPLC method useful for the analysis of the grapevine phytoalexins resveratrol, its β-D-glucoside, ε-viniferin, and pterostilbene in leaf extracts was developed by coupling diode array detection and fluorometry. Phytoalexins were extracted
- Jeandet, Philippe,Breuil, Anne Celine,Adrian, Marielle,Weston, Leslie A.,Debord, Sylvain,Meunier, Philippe,Maume, Gabrielle,Bessis, Roger
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- Metabolism of stilbene phytoalexins by botrytis cinerea: 1. Characterization of a resveratrol dehydrodimer
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Resveratrol, a grapevine phytoalexin, is metabolized by a laccase-like stilbene-oxidase of Botrytis cinerea, the causal organism for grey mould. Characterization of one major metabolite formed during this degradation process as a resveratrol dehydrodimer
- Breuil, Anne-Celine,Adrian, Marielle,Pirio, Nadine,Meunier, Philippe,Bessis, Roger,Jeandet, Philippe
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- Laccase-Catalyzed Dimerization of Piceid, a Resveratrol Glucoside, and its Further Enzymatic Elaboration
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The laccase-catalyzed oxidation of piceid, the 3-β-D-glucopyranosyl derivative of the stilbenic phytoalexin resveratrol, allowed isolation of the corresponding β-5 like trans-dehydrodimer in good yield (45%) avoiding chromatography. This compound was then
- Gavezzotti, Paolo,Bertacchi, Federica,Fronza, Giovanni,K?en, Vladimír,Monti, Daniela,Riva, Sergio
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- Applications of Amurensin H derivatives in treating and prevention liver related diseases
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The invention discloses applications of Amurensin H derivatives shown as a formula (I) and (II) and pharmaceutically acceptable salt thereof in the preparation of drugs for treating and/or preventingliver related diseases, and also discloses the preparation method of a compound, and applications of the pharmaceutical composition of the compound in the preparation of the drugs for treating and/orpreventing the liver related diseases.
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Paragraph 0164-0169
(2019/11/20)
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- Aerobic oxidative coupling of resveratrol and its analogues by visible light using mesoporous graphitic carbon nitride (mpg-C3N4) as a bioinspired catalyst
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The first aerobic oxidative coupling of resveratrol and its analogues by mesoporous graphitic carbon nitride as a bioinspired catalyst with visible light has been developed. With this method, δ-viniferin and its analogues were synthesized in moderate to high yield. The metal-free conditions, visible-light irradiation, and the ideal oxidant, molecular oxygen, make this coupling reaction environmental friendly and practical. Copyright
- Song, Tao,Zhou, Bo,Peng, Guang-Wei,Zhang, Qing-Bao,Wu, Li-Zhu,Liu, Qiang,Wang, Yong
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p. 678 - 682
(2014/01/23)
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- Metal incorporated Horseradish Peroxidase (HRP) catalyzed oxidation of resveratrol: Selective dimerization or decomposition
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Horseradish Peroxidase (HRP) is a commercially available and prevalently used peroxidase with no specific substrate binding domain. However, after being incorporated with different metal cations, new catalytic functions were found in biomimetic oxidation of resveratrol. Based on the results of screening, Ca, Cu, Fe and Mn incorporated enzymes showed distinctive effects, either decomposition or dimerization products were observed.
- Li, Chang,Xu, Xiaofei,Lu, Jing,Wang, Lin,Pan, Yuanjiang
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p. 22976 - 22980
(2013/11/19)
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- A joint experimental and theoretical investigation on the oxidative coupling of resveratrol induced by copper and iron ions
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Currently, a mounting interest exists on the biological activity of polyphenolic compounds, which have been suggested to exert positive effects on the human health. In this paper we report the first electrospray ionization mass spectrometry (ESI-MS) study on the gas-phase production of isomeric δ-viniferin and ε-viniferin dimers in racemic form, starting from acetonitrile/water solutions containing resveratrol and CuSO4 or FeCl3, respectively. Interestingly, the formation of racemic δ-viniferin dehydrodimer is observed in ESI-MS experiments carried out on resveratrol-copper mixtures, while the analogous resveratrol-iron reaction affords the racemic ε-viniferin dehydrodimer. The use of gas-phase techniques and of ab initio calculations, at BHandHLYP/LACV3P + +** level of theory, allowed us to elucidate some important aspects of these reaction mechanisms. In particular, a different stability for the resveratrol radicals involved in the oxidative coupling has been obtained in the presence of copper ion, favoring the formation of δ-viniferin, as proposed for the in vivo mechanism where copper is able to switch the resveratrol from an antioxidant to a prooxidant agent. Finally, the structure-reactivity relationship has been investigated for synthetic analogues of resveratrol, showing the crucial role of the OH group in para position.
- Tamboli, Vajir F.,Re, Nazzareno,Coletti, Cecilia,Defant, Andrea,Mancini, Ines,Tosi, Paolo
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body text
p. 55 - 63
(2012/08/28)
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- PH-switched HRP-catalyzed dimerization of resveratrol: A selective biomimetic synthesis
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A selective, concise and green biomimetic synthesis strategy of seven resveratrol dimers from natural resveratrol monomer as starting material is described. By succinct adjustment of environmental pH, the enzyme used, horseradish peroxidase (HRP), can perform in three distinctly different patterns and five dimers form with considerable selectivity. Two other derivative dimers are subsequently synthesized.
- Li, Chang,Lu, Jing,Xu, Xiaofei,Hu, Ruilin,Pan, Yuanjiang
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supporting information
p. 3281 - 3284
(2013/01/16)
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- Antioxidant-based lead discovery for cancer chemoprevention: the case of resveratrol
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Resveratrol is a well-known natural antioxidant and cancer chemopreventive agent that has attracted much nterest in the past decade. Resveratrol-directed compounds were synthesized, and their antioxidant effects gainst reactive oxygen species (ROS)-induced DNA damage, their prooxidant effects on DNA damage in he presence cupric ions, and their cytotoxic and apoptosis-inducing effects on human promyelocytic leukemia(HL-60) cells were investigated in vitro. It was found that the compounds bearing o-diphenoxyl groups exhibited remarkably higher activities in inhibiting ROS-induced DNA damage, accelerating DNA damage in the presence cupric ions, and inducing apoptosis of HL-60 cells compared with the ones bearing no such groups. The detail mechanism of the structure-activity relationship was also studied by the oxidative product analysis of resveratrol and its analogues with galvinoxyl radical or cupric ions and UV-visible spectra change in the presence cupric ions. This study reveals a good and interesting correlation between antioxidant and prooxidant activity, as well as cytotoxicity and apoptosis-inducing activity against HL-60 cells, and provides an idea for designing antioxidant-based cancer chemoprevention agents. ?2009 American Chemical Society.
- Qian, Yi-Ping,Cai, Yu-Jun,Fan, Gui-Juan,Wei, Qing-Yi,Jie, Yang,Zheng, Li-Fang,Li, Xiu-Zhuang,Fang, Jian-Guo,Bo, Zhou
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experimental part
p. 1963 - 1974
(2009/12/31)
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- Radical-scavenging activity and mechanism of resveratrol-oriented analogues: Influence of the solvent, radical, and substitution
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(Chemical Equation Presented). Resveratrol (3,5,4′-trihydroxy-trans- stilbene, 3,5,4′-THS) is a well-known natural antioxidant and cancer chemopreventive agent that has attracted much interest in the past decade. To find a more active antioxidant and investigate the antioxidative mechanism with resveratrol as the lead compound, we synthesized 3,5-dihydroxy-trans-stilbene (3,5-DHS), 4-hydroxy-trans-stilbene (4-HS) 3,4-dihydroxy-trans-stilbene (3,4-DHS), 4,4′-dihydroxy-trans-stilbene (4,4′-DHS), 4-hydroxy-3-methoxy-trans-stilbene (3-MeO-4-HS), 4-hydroxy-4′-methoxy- trans-stilbene (4′-MeO-4-HS), 4-hydroxy-4′-methyl-trans-stilbene (4′-Me-4-HS), 4-hydroxy-4′-nitro-trans-stilbene (4′-NO 2-4-HS), and 4-hydroxy-4′-trifluoromethyl-trans-stilbene (4′-CF3-4-HS). The radical-scavenging activity and detailed mechanism of resveratrol and its analogues (ArOHs) were investigated by the reaction kinetics with galvinoxyl (GO?) and 2,2-diphenyl-1- picrylhydrazyl (DPPH?) radicals in ethanol and ethyl acetate at 25°C, using UV-vis spectroscopy. It was found that the reaction rates increase with increasing the electron-rich environment in the molecules, and the compound bearing o-dihydroxyl groups (3,4-DHS) is the most reactive one among the examined resveratrol analogues. The effect of added acetic acid on the measured rate constant for GO?-scavenging reaction reveals that in ethanol that supports ionization solvent besides hydrogen atom transfer (HAT), the kinetics of the process is partially governed by sequential proton loss electron transfer (SPLET). In contrast to GO?, DPPH ? has a relatively high reduction potential and therefore enhances the proportion of SPLET in ethanol. The relatively low rate constants for the reactions of ArOHs with GO? or DPPH? in ethyl acetate compared with the rate constants in ethanol prove that in ethyl acetate these reactions occur primarily by the HAT mechanism. The contribution of SPLET and HAT mechanism depends on the ability of the solvent to ionize ArOH and the reduction potential of the free radical involved. Furthermore, the fate of the ArOH-derived radicals, i.e., the phenoxyl radicals, was investigated by the oxidative product analysis of ArOHs and GO? in ethanol. The major products were dihydrofuran dimers in the case of resveratrol, 4,4′-DHS, and 4-HS and a dioxane-like dimer in the case of 3,4-DHS. It is suggested from the oxidative products of these ArOHs that the hydroxyl group at the 4-position is much easier to subject to oxidation than other hydroxyl groups, and the dioxane-like dimer is formed via an o-quinone intermediate.
- Shang, Ya-Jing,Qian, Yi-Ping,Liu, Xiao-Da,Dai, Fang,Shang, Xian-Ling,Jia, Wen-Qiang,Liu, Qiang,Fang, Jian-Guo,Zhou, Bo
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experimental part
p. 5025 - 5031
(2009/10/17)
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- Regioselective Oxidative Coupling of 4-Hydroxystilbenes: Synthesis of Resveratrol and ε-Viniferin (E)-Dehydrodimers
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Treatment of 5-[2-(4-hydroxyphenyl)vinyl]benzene-1,3-diol (resveratrol) with an equimolar amount of silver(I) acetate in dry MeOH at 50 °C for 1 h followed by chromatographic purification with a short silica gel column allowed the isolation of its (E)-deh
- Sako, Magoichi,Hosokawa, Hiroyuki,Ito, Tetsuro,Iinuma, Munekazu
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p. 2598 - 2600
(2007/10/03)
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- Evaluation of resveratrol derivatives as potential antioxidants and identification of a reaction product of resveratrol and 2,2-diphenyl-1- picryhydrazyl radical
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Resveratrol (3,4',5-trihydroxy-trans-stilbene), an antioxidant from grapes, and five other polyhydroxystilbenes were synthesized. Their antioxidative properties were evaluated in two model systems [pure lipid oxidation using the Rancimat method and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging model.] 3,3',4,5'-Tetrahydroxystilbene, 3,3',4,5,5'- pentahydroxystilbene, and 3,4,4',5-tetrahydroxystilbene were found to be more active than resveratrol in both models. A dimer of resveratrol was identified as the major radical reaction product when resveratrol was reacted with DPPH radicals.
- Wang, Mingfu,Jin, Yi,Ho, Chi-Tang
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p. 3974 - 3977
(2007/10/03)
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