Three-component reaction of sugar hydroxylactone, amine and isocyanide for the synthesis of iminosugars

The Ugi four-centre three-component strategy has been developed for the synthesis of iminosugars in good yields under catalyst-free conditions. This method proceeds through a bicyclic N-acyl-iminium intermediate followed by the attack of isonitrile resulting in the formation of dihydroxypyroglutamic acid, which is a core moiety of many biologically important natural products.