[Synthesis of oligosaccharide fragments of O-specific polysaccharides of Shigella flexneri. III. Synthesis of the tetrasaccharide Glc alpha 1-3Rha alpha 1-2(Glc alpha 1-3)Rha alpha 1-OMe and the pentasaccharide GlcNAc beta 1-2(Glc alpha 1-3)Rha alpha 1-2(Glc alpha 1-3)Rha alpha 1-OMe].

Two synthetic schemes to prepare the title branched tetrasaccharide and pentasaccharide are described. These oligosaccharides represent fragments of the O-antigenic polysaccharides of Shigella flexneri serotype 5b.

[Synthesis of oligosaccharide fragments of O-specific Shigella flexneri polysaccharides. II. Synthesis of trisaccharide Glc alpha1----3RHa alpha1----2Rha alpha1----OMe and tetrasaccharide GlcNAc beta1----2(Llc alpha1----3)Rha alpha1----2Rh alpha1----OMe].

Methyl glycosides of the title linear trisaccharide and branched tetrasaccharide were synthesized by stepwise glycosylation. These oligosaccharides represent the fragments of O-antigenic polysaccharides of Shigella flexneri serotypes 2b, 3a, 5b, and X.

[Immunochemical analysis of oligosaccharide fragments of O-specific Shigella flexneri polysaccharides].

Comparison of inhibitory properties of several synthetic oligosaccharides related to Sh. flexneri O-specific polysaccharides, namely Glc alpha 1-3Rha alpha 1-OMe, Glc alpha 1-3Rha alpha 1-2Rha alpha 1-OMe, Rha alpha 1-2(Glc alpha 1-3)Rha alpha 1-OMe, GlcNAc beta 1-2(Glc alpha 1-3)Rha alpha 1-OMe, and GlcNAc beta 1-2(Glc alpha 1-3) Rha alpha 1-2Rha alpha 1-OMe, using passive haemagglutination reaction demonstrated the tetrasaccharide to possess the highest activity in V; 7,8-anti-7,8 immune system. Among the oligosaccharides under study, only Rha alpha 1-2(Glc alpha 1-3)Rha alpha 1-OMe exhibited moderate anti-V activity.