Imidazole acetic acid TAFIa inhibitors: SAR studies centered around the basic P′1 group

Abstract Structural modifications of the aminopyridine P 1 ′ group of imidazole acetic acid based TAFIa inhibitors led to the discovery of the aminocyclopentyl analog 28 , a 1 nM TAFIa inhibitor with CLT 50 functional activity of 14 nM but without selectivity against CPB. While not as active, aminobutyl derivative 27 provided an improved 6.7-fold selectivity for TAFIa versus CPB.