The composition of reducing sugars in aqueous solution : glyceraldehyde, erythrose, threose

Abstract

In the syrupy state, DL-glyceraldehyde, D-erythrose and D-threose consist mainly of mixtures of dimeric forms. Their aqueous solutions also contain some dimers; glyceraldehyde is present mainly as the aldehydrol, and the tetroses as mixtures of the furanoses and the aldehydrol. All the solutions contain some (> 1 %) of the aldehydo form. The proportion of the monomeric forms has been determined, from the 1H n.m.r. spectra, at various temperatures.