title: Stereoselective synthesis of α- and β-glycofuranosyl amides by traceless ligation of glycofuranosyl azides.
abstract: A highly stereoselective synthesis of α- or β-glycofuranosyl amides based on the traceless Staudinger ligation of glycofuranosyl azides of the galacto, ribo, and arabino series with 2-diphenylphosphanyl-phenyl esters has been developed. Both α- and β-isomers can be obtained with excellent selectivity from a common, easily available precursor. The process does not depend on the anomeric configuration of the starting azide but appears to be controlled by the C2 configuration and by the protection/deprotection state of the substrates. A mechanistic interpretation of the results, supported by (31)P NMR experiments, is offered and merged with our previous mechanistic analysis of pyranosyl azide ligation reactions.
authors.affiliation: Universitá degli Studi di Milano, Dipartimento di Chimica Organica e Industriale, Milano, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Nisic
authors.forename: Gaetano
authors.initials: G
authors.lastname: Speciale
authors.forename: Anna
authors.initials: A
authors.lastname: Bernardi
mesh_terms: D001386:Azides / Q000737:chemistry*; D004952:Esters; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry*; D008026:Ligation; D009682:Magnetic Resonance Spectroscopy; D013237:Stereoisomerism
chemical_list: D001386:Azides; D004952:Esters; D006027:Glycosides