Synthesis of monodeoxy and mono-O-methyl congeners of methyl beta-D-mannopyranosyl-(1-->2)-beta-D-mannopyranoside for epitope mapping of anti-Candida albicans antibodies.

A panel of six complementary monodeoxy and mono-O-methyl congeners of methyl beta-d-mannopyranosyl-(1-->2)-beta-d-mannopyranoside (1) were synthesized by stereoselective glycosylation of monodeoxy and mono-O-methyl monosaccharide acceptors with a 2-O-acetyl-glucosyl trichloroacetimidate donor, followed by a two-step oxidation-reduction sequence at C-2'. The beta-manno configuration of the final deprotected congeners 2-7 was confirmed by measurement of (1)J(C1,H1) heteronuclear and (3)J(1',2') homonuclear coupling constants. These disaccharide derivatives will be used to map the epitope recognized by a protective anti-Candida albicans monoclonal antibody C3.1 (IgG3) and to determine its key polar contacts with the binding site.