A Facile Synthesis of the Tetrasaccharide Repeating Unit of the O-Antigen from Cronobacter turicensis

作者：Qiao Yin; Gu Guofeng^*; Guo Zhongwu

来源：Journal of Carbohydrate Chemistry, 2015, 34(3): 121-132.

DOI：10.1080/07328303.2015.1027825

• Synthesis
• O-Antigen
• Regioselective glycosylation
• Cronobacter turicensis

GRAPHICAL ABSTRACT
[GRAPHICS]
The para-methoxyphenyl glycoside of a tetrasaccharide repeating unit, beta-D-GlcNAc-(1 -> 3)-beta-D-GlcNAc-(1 -> 3)-[alpha-D-Glc-(1 -> 2)]-alpha-L-Rha-O-(C6H4-p-OMe), of the polysaccharide O-antigen from Cronobacter turicensis was synthesized by an efficiently and linear assembly strategy. Consecutive glycosylation of the 3-O- and 2-O-positions of an L-rhamnopyranoside derivative with free 2,3-hydroxyl groups using a D-glucosaminyl and a D-glucosyl donor, respectively, accomplished a branched trisaccharide rapidly. Selective 3 '-O-deacetylation of the trisaccharide followed by glucosaminylation afforded the fully protected tetrasaccharide. Multistep protecting group manipulations of the fully protected tetrasaccharide eventually completed the synthesis of the target molecule.

• 出版日期2015-3-24
• 单位山东大学