Novel synthesis of 5-thio-hexopyranoside: preparation of 5-thio-d- and l-glucose and 1,6-anhydro-5-thio-l- and d-altrose
作者:Jun'ichi Uenishi、Hirohisa Ohmiya
DOI:10.1016/s0040-4020(03)00864-0
日期:2003.8
Asymmetric synthesis of both d- and l-isomers of 5-thioglucose and 1,6-anhydro-5-thioaltrose are described. The key intermediates, l- and d-threose diethylacetal derivatives, were derived by chemical transformation from d-xylose or d-arabinose and by Sharpless asymmetric dihydroxylation from γ-hydroxycrotylaldehyde diethylacetal. They transformed to γ-thiiranyl diethylacetal via trans-2,3-epoxy alcohol
描述了5-硫代葡萄糖和1,6-脱水-5-硫代altrose的d-和l-异构体的不对称合成。关键中间体1-苏糖和d-苏糖二乙缩醛衍生物是通过化学转化衍生自d-木糖或d-阿拉伯糖,以及通过Sharpless不对称二羟基化而得自γ-羟基丙烯醛二乙基缩醛。他们在七个步骤中通过反式-2,3-环氧醇转化为γ-噻吩基二乙缩醛。乙酸促进的γ-噻喃基二乙基缩醛的环化反应生成5-硫代吡喃糖苷。在酸性条件下除去保护基,分别得到5-硫代-d-和1-葡萄糖和1,6-脱水-5-硫代-1-和d-altrose。