A group of acyclic 2-alkyl-1, 1-diphenyl-2-(4-methylsulfonylphenyl) ethenes was designed for evaluation as selective cyclooxygenase-2 (COX-2) inhibitors. In vitro COX-1 and COX-2 isozyme inhibition structure–activity studies identified 1, 1-diphenyl-2-(4- methylsulfonylphenyl) hex-1-ene as a highly potent (IC50= 0.014 μM), and an extremely selective [COX-2 selectivity index (SI)> 7142], COX-2 inhibitor that showed superior anti- ...