Trityl-cyanoethylidene condensation of azidosaccharide derivatives as a route to hexosaminoglycans. Synthesis of the O-antigenic polysaccharide of Pseudomonas aeruginosa X (Meitert)]

Derivatives of azidosugars were shown to be stable under conditions of trityl-cyanoethylidene condensation. Tritylated 1,2-O-(1-cyano)ethylidene derivative of 2-azido-2-deoxy-beta-D-mannopyranosyl-(1----4)-L-rhamnopyranose was used as a starting material for the synthesis of ----3)-beta-D-ManNAc-(1----4)-alpha-L-Rha-(1----]n, the O-specific polysaccharide of Pseudomonas aeruginosa X (Meitert).