Asymmetric total syntheses of (+)-2,5-dideoxy-2,5-imino-d-glucitol [(+)-DGDP] and (−)-1-deoxymannojirimycin [(−)-DMJ] via an extended chiral 1,3-oxazine

Abstract

The asymmetric total syntheses of (+)-2,5-dideoxy-2,5-imino-d-glucitol [(+)-DGDP] 1 and (−)-1-deoxymannojirimycin [(−)-DMJ] 2 were achieved using an extended chiral 1,3-oxazine. The key synthetic strategies included extension of the chirality of anti,syn-oxazine 3 using diastereoselective dihydroxylation, and piperidine and pyrrolidine ring formation. Starting from readily available anti,syn-oxazine 3, (+)-DGDP 1 was synthesized in 5 steps with 31.6% overall yield and (−)-DMJ 2 was synthesized in 4 steps with 60.6% overall yield.