A series of potent and selective inhibitors of the inducible microsomal PGE2 synthase (mPGES-1) has been developed based on the indole FLAP inhibitor MK-886. Compounds 23 and 30 inhibit mPGES-1 with potencies in the low nanomolar range and with selectivities of at least 100-fold compared to their inhibition of mPGES-2, thromboxane synthase and binding affinity to FLAP. They also block the production of PGE2 in cell based assays but ...