title: Synthesis of di- and tri-saccharides with intramolecular NH-glycosidic linkages: molecules with flexible and rigid glycosidic bonds for conformational studies.
abstract: Attempted dephthalimidation of the trisaccharide 1-O-acetyl-3,4-di-O-benzyl- 2,6-di-O-(3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl )-alpha-D-mannopyranose (1) and its derivatives 2 and 3, as well as the disaccharide 1-O-acetyl-3,4,6-tri-O-benzyl-2-O-(3,4,6-tri-O-acetyl- 2-deoxy-2-phthalimido-beta-D-glucopyranosyl)-alpha-D-mannopyranose (13), with hydrazine hydrate in ethanol at 80 degrees C, produced the trisaccharide-6-O-(2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-beta-D- glucopyranosyl)-3,4-di-O-benzyl-beta-D-mannopyranose-3',4',6'-tri-O-a cet yl- beta-D-glucopyranose 1,2'-N:1',2-O-dianhydride (4) and 3,4,6-tri-O-benzyl-beta-D-mannopyranose 3',4',6'-tri-O-acetyl-beta-D-glucopyranose 1,2'-N:1',2-O-dianhydride (14), respectively, containing an intramolecular NH-glycosidic linkage. The conventional deblocking of compounds 4 and 14 gave the completely deblocked trisaccharide 6-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-beta-D-mannopyranose beta-D-glucopyranose 1,2'-N:1',2-O-dianhydride (6) and the disaccharide beta-D-mannopyranose beta-D-glucopyranose 1,2'-N:1',2-O-dianhydride (16), respectively, containing an intact intramolecular NH-glycosidic bond. The unusual intra NH-glycosyl character makes the linkage rigid, and therefore these compounds should not only be useful for NMR studies but also as substrates or inhibitors of GlcNAc-transferases.
authors.affiliation: Department of Molecular and Medical Genetics, University of Toronto, Ontario, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Goddat
authors.forename: A A
authors.initials: AA
authors.lastname: Grey
authors.forename: M
authors.initials: M
authors.lastname: Hricovíni
authors.forename: J
authors.initials: J
authors.lastname: Grushcow
authors.forename: J P
authors.initials: JP
authors.lastname: Carver
authors.forename: R N
authors.initials: RN
authors.lastname: Shah
mesh_terms: D000577:Amides / Q000737:chemistry*; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D017349:N-Acetylhexosaminyltransferases; D014312:Trisaccharides / Q000737:chemistry*
chemical_list: D000577:Amides; D004187:Disaccharides; D006027:Glycosides; D014312:Trisaccharides; D017349:N-Acetylhexosaminyltransferases