Synthesis of Halogenated-4-Nitrophenyl 2-deoxy-2-halogeno-pyranosides via N -Halogenosuccinimide Activated Glucal

Abstract

Reaction of 3,4,6-tri-O -acetyl-D-glucal with silver 4-nitrophenolate in the presence of N -iodosuccinimide and N -bromosuccinimide produced (2,6-dihalo-4-nitro)phenyl 2-halo-2-deoxy-α-D-glycopyranosides. Although bromination and iodination of the 4-nitrophenyl group could not be avoided, the resulting (2,6-dihalo-4-nitro)phenylated compounds can be used as substrates or covalent glycosidase inhibitors after deprotection. The stereoselectivity and regioselectivity of the halogenation reactions are described.