A series of 1, 5-diarylimidazoles with 4-methylsulfonylphenyl group were prepared and evaluated for the inhibitory activities against COX-2 catalyzed PGE2 production from LPS- induced RAW 264.7 cells. Most of synthesized 1, 5-diarylimidazoles exhibited strong inhibitory activities regardless of the position of the 4-methylsulfonylphenyl group. The 1, 5- diarylimidazoles with a halogen atom (3c–3h, 3n–3p) gave mostly excellent inhibitory ...