- Remarkable synergism in methylimidazole-promoted decarboxylation of substituted cinnamic acid derivatives in basic water medium under microwave irradiation: a clean synthesis of hydroxylated (E)-stilbenes
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A metal-free protocol for decarboxylation of substituted α-phenylcinnamic acid derivatives in aqueous media is developed, wherein a remarkable synergism between methylimidazole and aq NaHCO3 in polyethylene glycol under microwave furnished the corresponding para/ortho hydroxylated (E)-stilbenes in a mild and efficient manner. The critical role of water in facilitating the decarboxylation imparts an interesting facet to the synthetic utility of water mediated organic transformations. The developed protocol provides a clean alternative to the hitherto indispensable multistep approaches involving toxic quinoline and a copper salt combination as the common decarboxylating agent.
- Kumar, Vinod,Sharma, Abhishek,Sharma, Anuj,Sinha, Arun K.
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- 3. 4', 4 - three-stilbene esterification derivative and its preparation method and application (by machine translation)
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The invention relates to 3, 4', 4 - three-stilbene ester derivatives, the general structural formula: , In the formula R1 , R2 , R3 Group can be selected from and One or several. The invention also relates to 3, 4', 4 - three-stilbene ester derivatives of the preparation method, the preparation method of the "three wastes" less, easy processing, as fungicide pesticide production compared to the environmental protection. The derivatives as a new fungicide applied to controlling plant diseases, can be applied to the resistance of pathogenic bacteria, effect, and has the advantage of low cost. (by machine translation)
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Paragraph 0018
(2017/08/29)
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- Discovery of efficient stimulators for adult hippocampal neurogenesis based on scaffolds in dragon's blood
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Reduction of hippocampal neurogenesis caused by aging and neurological disorders would impair neural circuits and result in memory loss. A new lead compound (N-trans-3′,4'-methylenedioxystilben-4-yl acetamide 27) has been discovered to efficiently stimulate adult rats' neurogenesis. In-depth structure-activity relationship studies proved the necessity of a stilbene scaffold that is absent in highly cytotoxic analogs such as chalcones and heteroaryl rings and inactive analogs such as diphenyl acetylene and diphenyl ethane, and validated the importance of an NH in the carboxamide and a methylenedioxy substituent on the benzene ring. Immunohistochemical staining and biochemical analysis indicate, in contrast to previously reported neuroprotective chemicals, N-stilbenyl carboxamides have extra capacity for neuroproliferation-type neurogenesis, thereby providing a foundation for improving the plasticity of the adult mammalian brain.
- Liang, Jian-Hua,Yang, Liang,Wu, Si,Liu, Si-Si,Cushman, Mark,Tian, Jing,Li, Nuo-Min,Yang, Qing-Hu,Zhang, He-Ao,Qiu, Yun-Jie,Xiang, Lin,Ma, Cong-Xuan,Li, Xue-Meng,Qing, Hong
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p. 382 - 392
(2017/05/19)
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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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- Extraordinary radical scavengers: 4-mercaptostilbenes
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In the past decade, there was a great deal of interest and excitement in developing more active antioxidants and cancer chemoprevention agents than resveratrol, a naturally occurring stilbene. In this work, eight resveratrol-directed 4-mercaptostilbenes were constructed based on the inspiration that thiophenol should be a stronger radical scavenger than phenol, and their reaction rates with galvinoxyl (GO.) and 2,2-diphenyl-1-picrylhydrazyl (DPPH.) radicals in methanol and ethyl acetate were measured by using stopped-flow UV/Vis spectroscopy at 25 °C. Kinetic analysis demonstrates that 4-mercaptostilbenes are extraordinary radical scavengers, and the substitution of the 4-SH group for the 4-OH group in the stilbene scaffold is an important strategy to improve the radical-scavenging activity of resveratrol. Surprisingly, in methanol, some of the 4-mercaptostilbenes are 104-times more active than resveratrol, dozens of times to hundreds of times more effective than known antioxidants (α-tocopherol, ascorbic acid, quercetin, and trolox). The detailed radical-scavenging mechanisms were discussed based on acidified-kinetic analysis. Addition of acetic acid remarkably reduced the GO. and DPPH. radical-scavenging rates of the 4-mercaptostilbenes in methanol, a solvent that supports ionization, suggesting that the reactions proceed mainly through a sequential proton loss electron transfer mechanism. In contrast, an interesting acid-promoted kinetics was observed for the reactions of the 4-mercaptostilbenes with DPPH. in ethyl acetate, a solvent that weakly supports ionization. The increased ratio in rates is closely correlated with the electron-rich environment in the molecules, suggesting that the acceleration could benefit from the contribution of the electron transfer from the 4-mercaptostilbenes and DPPH.. However, the addition of acetic acid had no influence on the GO.-scavenging rates of the 4-mercaptostilbenes in ethyl acetate, due to the occurrence of the direct hydrogen atom transfer. Our results show that the radical-scavenging activity and mechanisms of 4-mercaptostilbenes depends significantly on the molecular structure and acidity, the nature of the attacking radical, and the ionizing capacity of the solvent. Copyright
- Cao, Xiao-Yan,Yang, Jie,Dai, Fang,Ding, De-Jun,Kang, Yan-Fei,Wang, Fu,Li, Xiu-Zhuang,Liu, Guo-Yun,Yu, Sha-Sha,Jin, Xiao-Ling,Zhou, Bo
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p. 5898 - 5905
(2012/06/30)
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- Design, synthesis, and biological evaluation of resveratrol analogues as aromatase and quinone reductase 2 inhibitors for chemoprevention of cancer
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A series of new resveratrol analogues were designed and synthesized and their inhibitory activities against aromatase were evaluated. The crystal structure of human aromatase (PDB 3eqm) was used to rationalize the mechanism of action of the aromatase inhibitor 32 (IC50 0.59 μM) through docking, molecular mechanics energy minimization, and computer graphics molecular modeling, and the information was utilized to design several very potent inhibitors, including compounds 82 (IC50 70 nM) and 84 (IC50 36 nM). The aromatase inhibitory activities of these compounds are much more potent than that for the lead compound resveratrol, which has an IC50 of 80 μM. In addition to aromatase inhibitory activity, compounds 32 and 44 also displayed potent QR2 inhibitory activity (IC 50 1.7 μM and 0.27 μM, respectively) and the high-resolution X-ray structures of QR2 in complex with these two compounds provide insight into their mechanism of QR2 inhibition. The aromatase and quinone reductase inhibitors resulting from these studies have potential value in the treatment and prevention of cancer.
- Sun, Bin,Hoshino, Juma,Jermihov, Katie,Marler, Laura,Pezzuto, John M.,Mesecar, Andrew D.,Cushman, Mark
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experimental part
p. 5352 - 5366
(2010/09/05)
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- Heck arylation of styrenes with arenediazonium salts: short, efficient, and stereoselective synthesis of resveratrol, DMU-212, and analogues
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Short, efficient, and stereoselective synthesis of the trans-stilbenes resveratrol, DMU-212, and analogues of both compounds are described. The synthesis of these important anti-cancer agents feature the palladium catalyzed Heck-Matsuda arylation of styre
- Moro, Angélica Venturini,Cardoso, Flávio Sega P.,Correia, Carlos Roque D.
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p. 5668 - 5671
(2008/12/22)
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- An unusual, mild and convenient one-pot two-step access to (E)-stilbenes from hydroxy-substituted benzaldehydes and phenylacetic acids under microwave activation: a new facet of the classical Perkin reaction
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A mild and convenient one-pot two-step synthesis of hydroxystilbenes with trans selectivity has been developed through a modified Perkin reaction between benzaldehydes and phenylacetic acids bearing 4- or 2-hydroxy substitution at the aromatic ring, in the presence of piperidine-methylimidazole and polyethylene glycol under microwave irradiation. The observation of a simultaneous condensation-decarboxylation leading to the unusual formation of hydroxystilbenes in lieu of α-phenylcinnamic acid reveals an interesting facet to the classical Perkin reaction. The developed protocol provides a green alternative to the prevalent methods employing a toxic decarboxylating agent in the form of quinoline/Cu salt, and the requirement for harsh protection-deprotection steps for the synthesis of hydroxylated stilbenes.
- Sinha, Arun K.,Kumar, Vinod,Sharma, Abhishek,Sharma, Anuj,Kumar, Rakesh
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p. 11070 - 11077
(2008/02/12)
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