| pubmed-article:2224902 | pubmed:abstractText | Treatment of benzyl O-beta-D-galactopyranosyl-(1----3)-2-acetamido-2- deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside with tert-butylchlorodiphenylsilane afforded the 6'-O-tert-butyldiphenylsilyl ether, which was converted into the 3',4'-O-isopropylidene derivative. Methylation and subsequent removal of protecting groups afforded benzyl O-(2-O-methyl-beta-D-galactopyranosyl)- (1----3)-2-acetamido-2-deoxy-beta-D-glucopyranoside (7). The trisaccharide methyl O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-O-(2- acetamido-2-deoxy-beta-D-glucopyranosyl)-(1----3)-beta-D-galactopyranosi de (17) and the tetrasaccharide O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-O-(2-acetamido-2-deoxy-b eta-D- glucopyranosyl)-(1----3)-O-beta-D-galactopyranosyl-(1----4)-D-glucopyran ose (32), both containing the 2'-O-methyllacto-N-biose I unit at the nonreducing end, were synthesized, and the structures of 7, 17, and 32 were confirmed by 13C-n.m.r. spectroscopy. | lld:pubmed |
