A new synthetic route towards iminosugars starting from chiral epoxyamides is described. The strategy, by which a single precursor. the alpha,beta-epoxyamide obtained from 6-O-trityl-2,3-O-isopropylidene-D-ribose and a sulphur ylide, can be transformed into different iminosugars, is based on the combination of a regioselective epoxide opening and stereospecific intramolecular displacements. (C) 2003 Elsevier Ltd. All rights reserved.