2,2-Diphenyl-1-picrylhydrazyl hydrate, a stable free radical, is an α-glucosidase inhibitor

Glycosidases play a pivotal role in processing of various glycoproteins and glycolipids. It is well known that glycosidases are also involved in a variety of degenerative metabolic disorders such as cancer and AIDS. In order to develop potent α-glucosidase inhibitors, we first screened 2,2-diphenyl-1-picrylhydrazyl hydrate as a candidate. 2,2-Diphenyl-1-picrylhydrazyl hydrate was found to inhibit α- and β-glucosidases as well as α- and β-mannosidases. It was also shown to be a non-competitive inhibitor of yeast α-glucosidase with a K_i value of 1.1×10^-6 M. Taken together, we anticipate that 2,2-diphenyl-1-picrylhydrazyl hydrate may be a potent inhibitor for some incurable metabolic disorders including AIDS.