Synthesis of capsular polysaccharide oligomers of Salmonella typhi, bacteria originated from typhoid fever

Article abstract of DOI:10.1016/s0040-4020(99)00869-8

The highly antigenic capsular polysaccharide of Salmonella typhi is a polysaccharide made out of N-acetyl D-galactosaminuronic acid units connected together through an α(1→4) linkage. Most of the hydroxyl groups at C-3 are acetylated. In order to determine the minimal size of fragments required for eliciting a significant immunological response, the corresponding di, tri, tetra and hexasaccharides have been chemically synthesized. The strategy is based on the use of anomeric S-xanthates of 2-azido-2-deoxy-D- galactopyranosyl derivatives as glycosyl donors. It has been shown that tetra and hexasaccharides are able to inhibit antibody binding by native polysaccharide.