title: Synthesis of 5-O-oligoglucosyl extended α-(2→4)-Kdo disaccharides corresponding to inner core fragments of Moraxellaceae lipopolysaccharides.
abstract: The heptose-deficient inner core of the lipopolysaccharide of several pathogenic strains of the Moraxellaceae family (Moraxella, Acinetobacter) and of Bartonella henselae, respectively, comprises an α-D-glucopyranose attached to position 5 of Kdo. In continuation of the synthesis of fragments of Acinetobacter haemolyticus LPS, the branched α-Glcp-(1 → 5)[α-Kdo-(2 → 4)]-α-Kdo trisaccharide motif was elaborated. The glycosylation of a suitably protected, α-(2 → 4)-interlinked Kdo-disaccharide was achieved in high yield and fair anomeric selectivity using a 4,6-O-benzylidene N-phenyltrifluoroacetimidate glucosyl donor. Subsequent regioselective reductive benzylidene opening afforded a trisaccharide acceptor, which was extended with β-D-glucopyranosyl and isomaltosyl residues. Global deprotection provided tri- to pentasaccharide structures corresponding to the inner core region of A. haemolyticus lipopolysaccharide.
authors.affiliation: Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
authors.forename: Barbara
authors.initials: B
authors.lastname: Pokorny
authors.affiliation: Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria. Electronic address: paul.kosma@boku.ac.at.
authors.forename: Paul
authors.initials: P
authors.lastname: Kosma
mesh_terms: D060326:Chemistry Techniques, Synthetic; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry*; D008070:Lipopolysaccharides / Q000737:chemistry*; D044007:Moraxellaceae / Q000737:chemistry*; D013237:Stereoisomerism; D014312:Trisaccharides / Q000737:chemistry
chemical_list: D004187:Disaccharides; D008070:Lipopolysaccharides; D014312:Trisaccharides; D005947:Glucose
keywords: Acinetobacter; Glycosylation; Kdo; Lipopolysaccharide; Oligosaccharide synthesis