2-Oxo-1,2-dihydropyridinyl-3-yl amide-based GPa inhibitors: Design, synthesis and structure-activity relationship study.

Glycogen phosphorylase (GP), which plays a crucial role in the conversion of glycogen to glucose-1-phosphate, is a target for therapeutic intervention in diabetes. In this study, we report the design and synthesis of 29 new derivatives of 2-oxo-1,2-dihydro pyridin-3-yl amides, as potential inhibitors of GP. The hit rate (45%) was high with 13 compounds inhibiting GPa (between 33% at 4.40 mM and an IC50 of 1.92 μM). Two lead compounds were identified as compounds exhibiting good GPa inhibition (IC50 = 2.1 and 1.92 μM). SAR analysis of these compounds revealed sensitivity of GPa to the length of the 2-oxo-1,2-dihydro pyridin-3-yl amide derivative and a preference for inclusion of a 3,4-dichlorobenzyl moiety.