Iminosugars from α,β-epoxyamides. Part 1: Synthetic approach to hydroxylated piperidine derivatives

A new synthetic route towards iminosugars starting from chiral epoxyamides is described. The strategy, by which a single precursor, the α,β-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.