Abstract An efficient asymmetric synthesis of isofagomine, based on a precursor containing three differentiated hydroxyl functions, is described. The side product in the key alkylation step is converted into (2S, 3R, 4R)-2, 4-bis (hydroxymethyl)-3-hydroxypyrrolidine, a new C 6 pyrrolidine azasugar, which inhibits α-glucosidase from yeast.
