As a new approach to the synthesis of aldosuloses (osones), epimeric pairs of the allylic alcohols, 1 and 2, and 4 and 5, were oxidized to the corresponding vinyl ketones, 3 and 6, respectively. Degradation of the latter by reductive ozonolysis and hydrolysis gave D-glycero-tetrosulose and D-arabino-hexosulose (D-glucosone), respectively.