128294-47-3Relevant articles and documents
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
Kumar, Vinod,Sharma, Abhishek,Sharma, Anuj,Sinha, Arun K.
, p. 7640 - 7646 (2007)
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.
3. 4', 4 - three-stilbene esterification derivative and its preparation method and application (by machine translation)
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, (2017/08/29)
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)
Extraordinary radical scavengers: 4-mercaptostilbenes
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
, p. 5898 - 5905 (2012/06/30)
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