7-Phenyl-imidazoquinolin-4(5H)-one derivatives as selective and orally available mPGES-1 inhibitors

To identify compounds with strong mPGES-1 inhibitory activity and clear in vitro ADME profile, we optimized the lead compound 1 by carrying our substitutions at the C(7)- and C(8)-positions. Replacement of the bromine atom of 1 with various substituents led to identification of the phenyl group as the best C(7)-substituent giving strong inhibitory activity with good in vitro ADME profile. Further SAR examination on both the C(2)- and the C(7)-phenyl groups provided compound 39 as the best candidate for further development. Compound 39 exhibited strong mPGES-1 inhibitory activity (IC50=4.1nM), potent cell-based functional activity (IC50=33nM) with good mPGES-1 selectivity (over 700-fold), excellent in vitro ADME profile, and good oral absorption in rat PK study.