Stereoselective synthesis of O-serinyl/threoninyl-2-acetamido-2-deoxy-alpha- or beta-glycosides.
General glycosidation methodology has been developed which can selectively provide 2-acetamido-2-deoxy-alpha- or beta-glycosides of beta-hydroxy-alpha-amino acid derivatives [glucopyranoside-(8, 43), galactopyranoside- (9, 13), mannopyranoside- (10), lactoside analogs (11, 38) and 3-O-beta-galactopyranosyl-mannopyranoside (12)] stereoselectively in excellent yield from the highly nucleophilic alpha-imino esters (Schiff bases) of L-serine and L-threonine. Various glycosides were converted via their amino and acetamido derivatives to Fmoc-protected serinyl- or threoninyl-glycosides (24-28, 37, 41, 46) which are all suitable building blocks for the solid-phase synthesis of O-glycopeptides. Complete 1H- and 13C-NMR data are provided for all compounds.
Szabó
L
L
Department of Chemistry, University of Arizona, Tucson 85721, USA.
Ramza
J
J
Langdon
C
C
Polt
R
R
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D006027:Glycosides / Q000138:chemical synthesis*; D006031:Glycosylation; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D012545:Schiff Bases; D012694:Serine / Q000737:chemistry*; D013912:Threonine / Q000737:chemistry*
D006027:Glycosides; D012545:Schiff Bases; C008245:lactosides; D013912:Threonine; D012694:Serine