An efficient synthesis of the four mono methylated isomers of (+)-catechin including the major metabolites and of some dimethylated and trimethylated analogues through selective protection of the catechol ring
作者:Cécile Cren-Olivé、Stéphane Lebrun、Christian Rolando
DOI:10.1039/b107340k
日期:2002.3.8
The four monomethylated isomers of (+)-catechin in positions 3′, 4′, 5 and 7, two dimethylated derivatives, the 5,7-dimethylcatechin and the 3′,4′-dimethylcatechin and two trimethylated isomers of (+)-catechin in positions 3′, 5, 7 and 4′, 5, 7 were synthesized by a new method based on successive and selective protections of the various phenol functions present on (+)-catechin. The key step was the selective protection of the catechol ring with dichlorodiphenylmethane and di-tert-butyldichlorosilane.
(+)-儿茶素在 3'、4'、5 和 7 位的四种单甲基化异构体,两种二甲基化衍生物,5,7-二甲基儿茶素和 3',4'-二甲基儿茶素以及 (+)-儿茶素的两种三甲基化异构体基于对(+)-儿茶素上存在的各种酚官能团的连续和选择性保护,通过一种新方法合成了位置3'、5、7和4'、5、7的儿茶素。关键步骤是用二氯二苯基甲烷和二叔丁基二氯硅烷选择性保护儿茶酚环。