title: Convergent synthesis of higher-order oligosaccharides corresponding to the cell-wall polysaccharide of the beta-hemolytic Streptococci group A. A branched hexasaccharide hapten.
abstract: A convergent synthesis of a hexasaccharide corresponding to the cell-wall polysaccharide of the beta-hemolytic Streptococci Group A is described. The strategy relies on the preparation of a key branched trisaccharide unit alpha-L-Rhap-(1----2)-[beta-D-GlcpNAc-(1----3)]-alpha-L-Rhap which functions both as a glycosyl acceptor and donor. The hexasaccharide is obtained after only three glycosylation reactions. This fully functionalized unit can serve, in turn, as a glycosyl acceptor or donor for the synthesis of higher-order structures. Deprotection gives a hexasaccharide for use as a hapten in immunochemical studies. The characterization of all compounds by high resolution 1H- and 13C-n.m.r. spectroscopy is also described.
authors.affiliation: Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada.
authors.forename: K B
authors.initials: KB
authors.lastname: Reimer
authors.forename: S L
authors.initials: SL
authors.lastname: Harris
authors.forename: V
authors.initials: V
authors.lastname: Varma
authors.forename: B M
authors.initials: BM
authors.lastname: Pinto
mesh_terms: D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000737:chemistry; D006241:Haptens / Q000737:chemistry; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009844:Oligosaccharides / Q000138:chemical synthesis*; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D013297:Streptococcus pyogenes / Q000737:chemistry*
chemical_list: D006241:Haptens; D009844:Oligosaccharides; D011135:Polysaccharides, Bacterial