The synthesis of 1-deoxynojirimycin (DNJ) derivatives is described from D-glucono-delta-lactone. The DNJ derivatives were obtained via a sequence that included a stereoselective intramolecular Huisgen reaction, decomposition to an aziridine, and its subsequent reaction with a nucleophile. Minimization of allylic strain in the transition state accounts for the stereoselectivity of the cycloaddition reaction.