Efficient Strategy for α-Selective Glycosidation of <scp>d</scp>-Glucosamine and Its Application to the Synthesis of a Bacterial Capsular Polysaccharide Repeating Unit Containing Multiple α-Linked GlcNAc Residues
Yanxin Zhang, Han Zhang, Ying Zhao, Zhongwu Guo, Jian Gao
Abstract
An efficient α-selective glycosylation method was developed for the synthesis of 2-deoxy-2-amino-d-glucosides based on synergetic α-directing effects of the TolSCl/AgOTf promotion system and the functional groups at the corresponding azido donor 6-O-position to exert steric β-shielding effect or remote participation in the glycosylation reaction. Its practicability was verified with a wide range of monosaccharide glycosyl acceptors and the first, one-pot synthesis of the challenging pentasaccharide repeating unit of an Acinetobacter baumannii K47 capsular polysaccharide.
Topics & Concepts
ChemistryGlycosylationGlycosyl donorMonosaccharidePolysaccharideGlycosylGlucosamineStereochemistryAcinetobacter baumanniiBiochemistryBacteriaPseudomonas aeruginosaGeneticsBiologyCarbohydrate Chemistry and SynthesisGlycosylation and Glycoproteins ResearchEnzyme Production and Characterization