Photochemical Access to Alkyl 3-Deoxyglycopyranosid-4-uloses.-The photoreductive ring opening of the oxirane ring of α,β-epoxyketones derived from carbohydrates is a mild method for the synthesis of β-hydroxyketones such as the chirons (III) and (VI) for the synthesis of natural compounds. -(COSSY, J.; IBHI, S.; Carbohydr.