Cyanohydrins from methyl 6-deoxy-2,3-O-isopropylidene-α-l-lyxo-hexofuranosid-4-ulose via Bucherer-Bergs and Strecker reactions

► The Strecker and Bucherer-Bergs reactions of 4-ulose afford four cyanohydrin isomers. ► Preferential formation of one cyanohydrin isomer was surprisingly observed. ► The structures of all isomers were unambiguously established by X-ray crystallography.