The synthesis of 2-acetamido-1,2-dideoxynojirimycin (2-acetamido-1,2,5-tri-deoxy-1,5-imino-D-glucitol) by a double inversion procedure starting from 1-deoxynojirimycin is reported. The key intermediates were the selectively protected N-benzyl-1,5-dideoxy-1,5-imino-4,6-O-isopropylidene-D-mannitol, the triflate ester N-benzyl-3-O-benzyl-1,5-dideoxy-1,5-imino-4,6-O-isopropylidene-2-O- (tri-fluoromethylsulfonyl)-D-mannitol, and 2-azido-N-benzyl-3-O-benzyl-1,2,5-tri-deoxy-1,5-imino-4,6-O- isopropylidene-D-glucitol, readily obtained in a sequence from 1-deoxynojirimycin. Thus 1-deoxynojirimycin served as a synthon compatible with the basic operations of carbohydrate chemistry.