title: Synthesis of the allo-analogue of trehalose.
abstract: Selective benzoylation of HO-2 and HO-2' of 4,6-O-benzylidene-alpha-D-glucopyranosyl 4,6-O-benzylidene-alpha-D-glucopyranoside with N-benzoylimidazole led to the exclusive formation of 2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranosyl 2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranoside. Oxidation of either the dibenzoate or the corresponding ditosylate with methyl sulphoxide--phosphorus pentaoxide gave the 3,3'-diulose, and subsequent reduction with borohydride gave the 3,3'diepimers having the allo-allo configuration. De-esterification and hydrolysis of the benzylidene substituents gave alpha-D-allopyranosyl alpha-D-allopyranoside.
mesh_terms: D004187:Disaccharides / Q000138:chemical synthesis*; D009682:Magnetic Resonance Spectroscopy; D008722:Methods; D008968:Molecular Conformation; D009904:Optical Rotation; D013237:Stereoisomerism; D014199:Trehalose / Q000138:chemical synthesis*
chemical_list: D004187:Disaccharides; D014199:Trehalose