Synthesis of oligosaccharides of l-fucose containing α- and β-anomeric configurations in the same molecule
作者:Harold M. Flowers
DOI:10.1016/0008-6215(83)84046-4
日期:1983.8
-fucopyranosyl bromide gave α- l -fucopyranosides stereospecifically, but 2,3,4-tri- O -acetyl-α- l -fucopyranosyl bromide gave mixtures with selectivity favouring the β anomer. A tetrasaccharide was prepared containing both α- and β- l -fucopyranosyl residues in the same molecule, as part of a structure occurring in some extracellular bacterial polysaccharides. The configuration and positions of substitution
摘要合成了一些含有d-葡萄糖和d-半乳糖的l-呋喃果糖基二,三和四糖。使用氰化汞和2-O-苄基-3,4-二-O-对硝基苯甲酰基-α-1-呋喃果糖基溴化物可立体定向产生α-1-呋喃果糖苷,但2,3,4-三-O-乙酰基-α-1-呋喃果糖基溴给出选择性有利于β端基异构体的混合物。制备了在同一分子中同时包含α-和β-1-呋喃二糖基残基的四糖,作为在一些细胞外细菌多糖中发生的结构的一部分。1 H-和13 Cn.mr数据清楚地表明了呋喃核糖基残基的取代构型和取代位置。