4-({2-[Isobutyl (phenylsulfonyl) amino]-5-(trifluoromethyl) phenoxy} methyl) benzoic acid (1) is a functional PGE2 antagonist selective for EP1 receptor subtype. Analogs of 1, in which the phenyl-sulfonyl moiety has been replaced with more hydrophilic heteroarylsulfonyl moieties, exhibited more optimized antagonist activity, while some of them showed in vivo antagonist activity. Structure–activity relationship (SAR) studies are also presented.
