An efficient approach to N-acetyl-d-glucosaminuronic acid-based sialylmimetics as potential sialidase inhibitors

A novel approach to the synthesis of β-glycosides of N-acetyl-d-glucosaminuronic acid, in six steps and good overall yield from N-acetyl-d-glucosamine, has been developed. The key synthetic step was the Lewis acid mediated O-glycosidation of methyl 1,3,4-tri-O-pivaloyl-N-acetyl-d-glucosaminuronate (11). Elaboration of glucosaminuronides 15 and 18 provided novel sialylmimetics 21 and 22, which showed inhibition of Vibrio cholerae sialidase.