1IntroductionAza-sugars, a class of polyhydroxylated pyrrolidine and piperidine, are powerful glyco-processing enzyme inhibitors and potential therapeutics for the treatment of diabetic, cancer, viral infection and other diseases[1].For example, N-hydroxyethyl-1-deoxynojirimycin (Miglitol) and N-butyl-1-deoxynojirimycin (Zavestca)have been approved for the treatment of type 2 diabetes and type 1 Gaucher disease, respectively. Numerous synthetic methods towards azasugars have been developed[1,2] which include various reductive and double-reductive amination between an azido/amino group and carbonyl groups and SN2 substitutions by nucleophilic amine to epoxides, halides, and other leaving groups. Aza-C-glycosides, azasugars with a C-linked aglycon,which often possess improved inhibition specificity and membrane permeability, have been obtained from azasugars via an elimination reaction followed by the addition of organometallic reagent, and from properly constructed substrates by an intramolecular or intermolecular conjugate additions of nucleophilic amines[3,4]. One of the major limitations associated with these procedures, however, is the accessibility of the intermediates,which highly depend on the stereochemistry of the hydroxy groups of the starting material to achieve regio-selective protection. Therefore, an easy access to molecules with both amine and α ,β-unsaturated ester (ketone) functionalities is desired.