Facile syntheses of the disaccharide repeating unit of the O-antigenic polysaccharide of Burkholderia pseudomallei strain 304b and its dimer and trimer.

A highly efficient strategy for the preparation of a disaccharide-repeating unit of the O-antigenic polysaccharide of Burkholderia pseudomallei strain 304b, and its dimer and trimer, has been developed through a regio- and stereoselective manner using p-methoxylphenyl 2,4,6-tri-O-benzoyl-α-D-glucopyranoside and 3-O-allyloxycarbonyl-2,4-di-O-benzoyl-6-deoxy-α-L-talopyranosyl trichloroacetimidate as the key synthons. The target molecules were equipped with a p-methoxylphenyl handle at the reducing terminus to allow for their further functionalization and attachment to a carrier protein.