ABSTRACT
The addition of 1-thio-D-glucose sodium salt to per-O-acetylated 1,2-dideoxy-1-nitro-D-arabino-hex-1-enitol, readily available from D-arabinose, afforded the corresponding 2-S-glycosylated 1-deoxy-1-nitro-D-mannitol and -D-glucitol peracetates. These, after deacetylation, were transformed by the Nef reaction to 2-thioepisophorose and 2-thiosophorose, respectively. The 2-thiodisaccharides easily epimerize in aqueous sodium bicarbonate at ambient temperature to a 1:4 equilibrium mixture. The predominant 2-thiosophorose was obtained crystalline. A 1H NMR study of the epimerization in deuterium oxide showed that the reaction involves an H-2 proton exchange mechanism.
Subject(s)
Disaccharides/chemical synthesis , Nitro Compounds/chemical synthesis , Carbohydrate Conformation , Carbohydrate Sequence , Glucose/analogs & derivatives , Glucose/metabolism , Magnetic Resonance Spectroscopy , Molecular Conformation , Molecular Sequence Data , Molecular StructureABSTRACT
The structures of the title compounds have been determined by X-ray crystallography, using direct methods, and have been refined to conventional final residual factors of R = 0.063 and R = 0.046, respectively.
