title: The synthesis of chemically modified disaccharide derivatives of the Shigella flexneri Y polysaccharide antigen.
abstract: Disaccharide analogs related to the 2-acetamido-2-deoxy-3-O-(alpha-L- rhamnopyranosyl)-beta-D-glucopyranose element of the Shigella flexneri Y polysaccharide antigen have been synthesized and used to map the binding site of murine monoclonal antibodies GC-4 and SYA/J6 by solid-phase inhibition assays. N-Acetyl, N-trifluoroacetyl and N-benzyloxycarbonyl derivatives of methyl-2-amino-4,6-O-benzylidene-2-deoxy-beta-D-glucopyranoside 1, 3, and 4 were glycosylated by rhamnopyranosyl bromide and thioglycoside donors 5 and 6. These in turn provided access to a series of alpha-L-Rha p-(1-->3)-beta-D-GlcNp-(1-->O)-Me disaccharide glycosides with amino 13, N-acetyl 10, N-propionyl 14, N-pivaloyl 15, and N-trifluoroacetyl 11 functionalities. Congeners of the disaccharide 10 were synthesized with monodeoxy groups introduced at the C-4 and C-6 positions of the GlcNAc residues and at the C-4' position of the rhamnose unit. Chlorosulfation of the selectively protected disaccharide 24, followed by reduction of the 4-chloro-4-deoxy compound 25, was used to prepare the 4-deoxy congener 27, while the C-6 and C-4' deoxy derivatives 31 and 23 were assembled from their respective pre-functionalized monosaccharide building blocks 29 and 19.
authors.affiliation: Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario.
authors.forename: F I
authors.initials: FI
authors.lastname: Auzanneau
authors.forename: H R
authors.initials: HR
authors.lastname: Hanna
authors.forename: D R
authors.initials: DR
authors.lastname: Bundle
mesh_terms: D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000737:chemistry*; D008969:Molecular Sequence Data; D019081:O Antigens; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D012763:Shigella flexneri / Q000737:chemistry* / Q000276:immunology
chemical_list: D004187:Disaccharides; D019081:O Antigens; D011135:Polysaccharides, Bacterial; C080450:2-acetamido-2-deoxy-3-O-rhamnopyranosylglucose