Synthesis of branched tri- to pentasaccharides representative of fragments of Shigella flexneri serotypes 3a and/or X O-antigens
作者:Julien Boutet、Catherine Guerreiro、Laurence A. Mulard
DOI:10.1016/j.tet.2008.08.080
日期:2008.11
Final Pd/C-mediated deprotection, run under a high pressure of hydrogen, ensured O-acetyl stability. All targets are parts of the O-antigen of Shigella flexneri 3a, a prevalent serotype. Non-O-acetylated oligosaccharides are shared by the S. flexneri serotype X O-antigen.
的2)的片段- [α-d-GLC p - (1→3)] - α-L-鼠李糖p - (1→2)-α-L-鼠李糖p - (1→3) - [AC →2]-α-L-鼠李糖p - (1→3)-β-d-GLC p NAc-(1→} ñ((E)AB AC CD)ñ。聚合物合成d(E)甲,CD (E)A,Ac CD(E)A是根据线性策略获得的,而BCD(E)A和B Ac CD(E)A是由适当的BC和D(E)A的缩合得到的建筑模块。寡糖合成为自己丙基糖苷,依靠(i)所述有效三氯化学,(ⅱ)共同EA烯丙基糖苷,和(iii)2 -向残余物trichloroacetamido-d-D-吡喃葡萄糖前体d。在氢气的高压下进行的最终Pd / C介导的脱保护,确保了O-乙酰基的稳定性。所有的靶标都是弗氏志贺氏菌3a(一种流行的血清型)的O-抗原的一部分。弗氏链球菌血清型X O-抗原共有非O-乙酰化的寡糖。