THE CONFIGURATION OF GLYCOSIDIC LINKAGES IN OLIGOSACCHARIDES: I. APPLICATION OF JACKSON AND HUDSON'S OXIDATION METHOD TO REDUCING DISACCHARIDES

Use of glycol-cleavage oxidations to assist in establishing the configuration of biose linkages is considered. The approach is based on degradation of disaccharides to yield compounds of simpler structure, all disaccharides of a given class yielding the same product. Thus, 1,6-D-aldohexopyranose disaccharides on oxidation yield one of two possible trialdehydes, the reducing end-unit being converted to glycolic aldehyde and the non-reducing end-unit to a dialdehyde of a type produced from simpler glycosides. These two compounds differ only in the configuration of the carbon atom which originally constituted the glycosidic center, α-linked disaccharides giving rise to one compound, and β-linked to the other. The relative contribution of the glycosidic center to the optical activity of these oxidation products is thereby enhanced and, accordingly, is expected to promote a large rotational difference between α- and β-compounds. Correlation of a 1,6-disaccharide of unknown configuration with known ones by comp...