Enzyme‐Catalyzed Synthesis of 1‐Deoxymannojirimycin, 1‐Deoxynojirimycin, and 1,4‐Dideoxy‐1,4‐imino‐ D ‐arabinitol

The title compounds 1, 2, and 3 are highly effective glycosidase inhibitors. They were synthesized from achiral starting compounds by enzyme-catalyzed CC coupling of dihydroxyacetone phosphate (→ 1, 2) or hydroxypyruvate (→ 3) with racemic 3-azido-2-hydroxypropanal via fructose, sorbose and xylulose derivatives and their subsequent enantioselective catalytic hydrogenation.