Abstract
A novel series of pyridones were discovered as potent EP3 antagonists. Optimization guided by EP3 binding and functional assays as well as by eADME and PK profiling led to multiple compounds with good physical properties, excellent oral bioavailability, and a clean in vitro safety profile. Compound 13 was identified as a lead compound as evidenced by the reversal of sulprostone-induced suppression of glucose-stimulated insulin secretion in INS 1E β-cells in vitro and in a rat ivGTT model in vivo. A glutathione adduction liability was eliminated by replacing the naphthalene of structure 13 with the indazole ring of structure 43.