Concise Synthesis of 1,4-Dideoxy-1,4-imino-ʟ-arabinitol (LAB) from d-Xylose by Intramolecular Stereospecific Substitution of a Hydroxy Group

We report a concise and green total synthesis of 1,4-dideoxy-1,4-imino-ʟ-arabinitol hydrochloride from naturally occurring d-xylose. The key step involves a stereospecific substitution of a hydroxy group, without prior derivatization, in which the only byproduct is water. This opens up a novel benign route to iminosugar derivatives with diverse biological activities.