title: [Synthesis of trisaccharide units from capsular polysaccharides of Streptococcus pneumoniae].
abstract: In the presence of silver silicate as promoter, the reaction of glycosyl bromide of 2-azido-2-deoxy-D-mannose with 1,6-anhydro-2,3-di-O-benzyl-beta-D- glucopyranose led to derivatives of the disaccharide beta-D-ManpNac-(1----4)-D- Glcp. The derivatives were activated into disaccharide halides and employed as glycosyl donors in block synthesis. By chain extension with L-rhamnose and D-glucose, four trisaccharides were synthesized. They represent components of capsular polysaccharide "repeating units" of various Streptococcus pneumoniae types, beta-D-Man-pNAc-(1----4)-alpha-D-Glcp-(1----2)-L-Rhap (type 19 F), beta-D-ManpNAc-(1----4)-alpha-D-Glcp-(1----3)-L-Rhap (type 19 A), beta-D-ManpNAc-(1----4)-alpha-D-Glcp-(1----4)-D-Glcp (type 9 A), and beta-D-ManpNAc-(1----4)-beta-D-Glcp-(1----4)-D-Glcp (type 9 V).
authors.affiliation: Institut für Organische Chemie, Universität Hamburg, 13 Bundesrepublik Deutschland.
authors.forename: H
authors.initials: H
authors.lastname: Paulsen
authors.forename: B
authors.initials: B
authors.lastname: Helpap
authors.forename: J P
authors.initials: JP
authors.lastname: Lorentzen
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D055598:Chemical Phenomena; D002621:Chemistry; D004187:Disaccharides; D005947:Glucose; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial; D012210:Rhamnose; D013296:Streptococcus pneumoniae; D014312:Trisaccharides / Q000138:chemical synthesis*
chemical_list: D004187:Disaccharides; D011135:Polysaccharides, Bacterial; D014312:Trisaccharides; D005947:Glucose; D012210:Rhamnose
vernacular_title: Synthese von Trisaccharid-einheiten der Kapselpoly-Saccharide von Streptococcus pneumoniae.