2,3:4,6-Di-O-isopropylidene-L-Sorbosone is an intermediate for the synthesis of L-Sorbosone (S677120), which is a compound that can be converted into L-Ascorbic Acid (A786990) by a novel enzyme, L-sorbosone dehydrogenase 1 (SNDH1), which is isolated from Ketogulonicigenium vulgare DSM 4025.