A formal synthesis of the natural growth promoting steroid brassinolide is described,which involves construction of side chain by 1,3-sulfoxide-hydroxyl transposition with methylation from(24S)- 22-E-24-sulfoxide 6 an...A formal synthesis of the natural growth promoting steroid brassinolide is described,which involves construction of side chain by 1,3-sulfoxide-hydroxyl transposition with methylation from(24S)- 22-E-24-sulfoxide 6 and(24R)-22-E-24-sulfoxide 9,respectively to (22S)-23-E-24-methyl compound 4.展开更多
A concise synthetic route leading to highly functional erythrina alkaloid skeletons has been developed.The key process is an oxidative carbon-carbon coupling followed by a conjugated addition.Based on this new strateg...A concise synthetic route leading to highly functional erythrina alkaloid skeletons has been developed.The key process is an oxidative carbon-carbon coupling followed by a conjugated addition.Based on this new strategy,a formal synthesis of demethoxyerythratidinone was completed in only 6 steps from 4-aminophenol.展开更多
A formal synthesis of betamethasone from 5α-pregnane-3β,16β,20S-triol is described.Key transformations are a bromination-acetylation of triol,an SN2 reaction of the resulting C16α-bromide with dimethylcopperlithiu...A formal synthesis of betamethasone from 5α-pregnane-3β,16β,20S-triol is described.Key transformations are a bromination-acetylation of triol,an SN2 reaction of the resulting C16α-bromide with dimethylcopperlithium to get the required C16β-methyl group,and a double hydroxylation to prepare the dihydroxyacetone side chain.展开更多
Enantiomerically pure 6-acetyl-1,3,3-trimethyl bicyclo[2.2.2]octan-2-one,a key inter- mediate for synthesis of(-)-patchouli alcohol,was facilely synthesized from the adduct of a monome- thylated(-)-carvone 2 and methy...Enantiomerically pure 6-acetyl-1,3,3-trimethyl bicyclo[2.2.2]octan-2-one,a key inter- mediate for synthesis of(-)-patchouli alcohol,was facilely synthesized from the adduct of a monome- thylated(-)-carvone 2 and methyl acrylate.展开更多
文摘A formal synthesis of the natural growth promoting steroid brassinolide is described,which involves construction of side chain by 1,3-sulfoxide-hydroxyl transposition with methylation from(24S)- 22-E-24-sulfoxide 6 and(24R)-22-E-24-sulfoxide 9,respectively to (22S)-23-E-24-methyl compound 4.
基金This work was supported by grants(20925205,21062026,2010GA014 and 2009CB522300) from National Natural Science Foundation of China,Yunnan Province and National Basic Research Program of China(973 Program).
文摘A concise synthetic route leading to highly functional erythrina alkaloid skeletons has been developed.The key process is an oxidative carbon-carbon coupling followed by a conjugated addition.Based on this new strategy,a formal synthesis of demethoxyerythratidinone was completed in only 6 steps from 4-aminophenol.
文摘A formal synthesis of betamethasone from 5α-pregnane-3β,16β,20S-triol is described.Key transformations are a bromination-acetylation of triol,an SN2 reaction of the resulting C16α-bromide with dimethylcopperlithium to get the required C16β-methyl group,and a double hydroxylation to prepare the dihydroxyacetone side chain.
基金This project was supported by the National Natural Science Foundation of China.
文摘Enantiomerically pure 6-acetyl-1,3,3-trimethyl bicyclo[2.2.2]octan-2-one,a key inter- mediate for synthesis of(-)-patchouli alcohol,was facilely synthesized from the adduct of a monome- thylated(-)-carvone 2 and methyl acrylate.
