title: Synthesis of 5-aminopentyl mono- to tri-saccharide haptens related to the species-specific glycopeptidolipids of Mycobacterium avium-intracellulare serovars 8 and 21.
abstract: The preparation of pyruvate acetal-containing 5-aminopentyl mono-, di-, and tri-saccharide fragments related to serovars 8 and 21 of the species-specific glycopeptidolipid of Mycobacterium avium-intracellulare is described. The saccharides were constructed by sequential coupling of the suitably protected 4,6-O-[(S)-1-methoxycarbonylethylidene]-D-glucopyranosyl trichloroacetimidates 6 and 7 to Z-protected 5-aminopentanol, to give the serovar 21 monosaccharide fragment 9 upon deblocking; and to ethyl 2-O-benzoyl-4-O-benzyl-1-thio-alpha-L-rhamnopyranoside (18), to give the corresponding ethyl 1-thio-disaccharides 21 and 23, respectively. Subsequent N-iodosuccinimide-promoted coupling of the latter with Z-protected 5-aminopentanol followed by deblocking of the products afforded the corresponding disaccharide fragments 26 (serovar 8) and 27 (serovar 21), respectively. Condensation of 21 with Z-protected 5-aminopentyl 3,4-di-O-benzyl-6-deoxy-alpha-L-talopyranoside (28) and subsequent deblocking of the resulting trisaccharide gave the serovar 8 fragment 5-aminopentyl O-(4,6-O-[(S)-1-carboxyethylidene]-3-O-methyl-beta-D-glucopyranosyl)- (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-6-deoxy-alpha-L-talopyranos ide (30).
authors.affiliation: Institut für Organische Chemie und Isotopenforschung, Universität Stuttgart, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Ziegler
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D006001:Glycoconjugates / Q000737:chemistry*; D006241:Haptens / Q000737:chemistry*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008969:Molecular Sequence Data; D015394:Molecular Structure; D015269:Mycobacterium avium Complex / Q000737:chemistry* / Q000145:classification; D009904:Optical Rotation; D012703:Serotyping; D014312:Trisaccharides / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D004187:Disaccharides; D006001:Glycoconjugates; D006241:Haptens; D007202:Indicators and Reagents; D014312:Trisaccharides