Unusual reactivity of pyruvated glycosyl donors during construction of rhizobial exopolysaccharide fragments

Article abstract of DOI:10.1002/prac.19973390196

Two pyruvated galactosyl donors, 2,3-di-O-benzoyl-4,6-0-[1-(R)-methoxycarbonyl(ethylidene)]-α-D- galactopyranosyl chloride (6) and trichloroacetimidate 13, were coupled to position 3 of suitably protected mono and disaccharide benzyl glucoside acceptors. For both donors, an unusual high content of the α-(1→3)-linked products was obtained. The corresponding β-(1→3)-linked di- and trisaccharides are related to exopolysaccharides of Rhizobium leguminosarum.