Chemical synthesis of the tumor-associated globo H antigen
作者:Satadru S. Mandal、Guochao Liao、Zhongwu Guo
DOI:10.1039/c5ra00759c
日期:——
A derivative of the tumor-associated globo H antigen, a complex hexasaccharide, was synthesized by a convergent and efficient [3 + 2 + 1] strategy using various glycosylation methods. All glycosylation reactions afforded good to excellent yields and outstanding stereoselectivity, including the installation of cis α-linked D-galactose and L-fucose. The longest linear sequence for this synthesis was
First synthesis of a pentasaccharide repeating unit of the O-antigenic polysaccharide from enterohaemorrhagic Escherichia coli O48:H21
作者:Rajib Panchadhayee、Anup Kumar Misra
DOI:10.1016/j.tetasy.2009.05.026
日期:2009.7
A concise synthesis of a pentasaccharide as its 4-methoxyphenyl glycoside, found in the O-antigenic polysaccharide of enterohaemorrhagic Escherichia coli O48:H21 has been achieved for the first time in excellent yield. Most of the intermediate steps are high yielding and the stereooutcome of each glycosylation step was excellent. Stereoselective glycosylation and removal of the 4-methoxybenzyl group were achieved in one-pot by tuning the reaction conditions. A late-stage TEMPO-mediated oxidation strategy has been adopted for the oxidation of a primary hydroxyl group to carboxylic acid. (C) 2009 Elsevier Ltd. All rights reserved.