Linear Synthesis of The Methyl Glycosides of Tri-, Tetra-, and Pentasaccharide Fragments of The<i>Shigella Flexneri</i>Serotype 5A<i>O</i>-Antigen
作者:Laurence A. Mulard、Joël Ughetto-Monfrin
DOI:10.1080/07328300008544096
日期:2000.1
3) is described. Compounds 1, 2 and 3 constitute the methyl glycosides of fragments of the O-specific polysaccharide of Shigella flexneri serotype 5a. Methyl 2,4-di-O-benzoyl-α-L-rhamnopyranosyl-(1→3)-2,4-di-O-benzoyl-α-L-rhamnopyranoside was an appropriate BC precursor for the synthesis of 1. For the synthesis of the branched targets 2 and 3, a benzyl group was best suited at position 2 of rhamnose
甲基α-D-吡喃葡萄糖基-(1→3)-α-L-鼠李吡喃糖基-(1→3)-α-L-鼠李糖吡喃糖苷(EBC-OMe,1),甲基α-L-鼠李糖吡喃糖基-( 1→2)-[α-D-吡喃葡萄糖基-(1→3)]-α-L-鼠李吡喃糖基-(1→3)-α-L-鼠李吡喃糖苷(A(E)BC-OMe,2)和甲基2-乙酰氨基-2-脱氧-β-D-吡喃葡萄糖基-(1→2)-α-L-鼠李吡喃糖基-(1→2)-[α-D-吡喃葡萄糖基-(1→3)]-α-L-描述了鼠李糖吡喃糖基-(1→3)-α-L-鼠李糖吡喃糖苷(DA(E)BC-OMe,3)。化合物1、2和3构成弗氏志贺氏菌血清型5a的O-特异性多糖的片段的甲基糖苷。甲基2,4-二-O-苯甲酰基-α-L-鼠李糖基-(1→3)-2,4-二-O-苯甲酰基-α-L-鼠李糖吡喃糖苷是合成1的合适BC前体。为了合成支链目标2和3,苄基最适合于鼠李糖C的2位。因此,甲基4 - O-苄基-