Glycosyl transfer by isopropenyl glycosides: Trisaccharide synthesis in one pot by selective coupling of isopropenyl and n-pentenyl glycopyranosides
作者:H.Keith Chenault、Alfredo Castro
DOI:10.1016/0040-4039(94)88449-8
日期:1994.12
O-Isopropenyl glycosides bearing ester protecting groups are activated as glycosyl donors by a variety of electrophiles. Diastereomerically pure β-glycoside products are formed in good yields. Selective activation of O-isopropenyl 2,3,4,6-tetra-O-pivaloyl-β-glucopyranoside in the presence of O-pent-4-enyl 2,3,4,6-tetra-O-benzyl-β-glucopyranoside allows two successive glycosyl couplings to be performed
带有酯保护基的O-异丙烯基糖苷被各种亲电试剂活化为糖基供体。非对映体纯的β-糖苷产物以良好的产率形成。在O-戊-4-烯基2,3,4,6-四-O-苄基-β-存在下的O-异丙烯基2,3,4,6-四-O-新戊酰基-β-吡喃葡萄糖苷的选择性活化吡喃葡萄糖苷可以在一个罐中进行两个连续的糖基偶联,从而以25%的收率得到三糖。