Synthesis of purine homo-N-nucleosides modified with coumarins as free radicals scavengers*
摘要:
Cross metathesis (CM) of 9-butenylpurines with 4-butenyloxycoumarin in the presence of Grubbs 2nd generation catalyst under MW irradiation resulted to conjugated compounds containing homo-N-nucleosides and coumarins. Analogous derivatives received by the CM reaction of 9-butenyl-6-piperidinylpurine with 6-or 7-butenyloxycoumarins, allyloxycoumarins or coumarinyl acrylate. These compounds were tested in vitro for their antioxidant activity and they present significant scavenging activity. The presence of a pentenyloxy moiety, the attachment position on coumarin ring as well as a purine homo-N-nucleoside group are considered as important structural features.
Copper-Catalyzed Three-Component Oxytrifluoromethylation of Alkenes with Sodium Trifluoromethanesulfinate and Hydroxamic Acid
作者:Xin-Yi Jiang、Feng-Ling Qing
DOI:10.1002/anie.201307595
日期:2013.12.23
Radical paths: The title reaction of olefins with NaSO2CF3 and N‐hydroxy‐N‐phenylacetamide at room temperature is described for the first time (see scheme). This reaction provides a practical and convenient route to a series of trifluoromethylated alcohols bearing a wide range of functional groups.
Rhodium(III)-Catalyzed Redox-Neutral [4 + 1]-Annulation of Unactivated Alkenes with Sulfoxonium Ylides
作者:Pinki Sihag、Masilamani Jeganmohan
DOI:10.1021/acs.joc.2c01324
日期:2022.8.19
Further, multiple transformations such as ring-expansion, reduction, aldol condensation, and Wittig reaction were carried out with indanones. Using this way, highly useful cyclic heterocycles such as indene, dihydroisocoumarin, and 1-indanilidene were prepared in a single step. A possible reaction mechanism was supported by deuterium labeling studies, competitive studies, and kinetic isotopic studies.