1,2-Diarylcyclopentenes as selective cyclooxygenase-2 inhibitors and orally active anti-inflammatory agents.
A series of 1,2-diarylcyclopentene methyl sulfones and sulfonamides have been shown to be remarkably potent and selective cyclooxygenase-2 (COX-2) inhibitors. The methyl sulfone analogs 7 showed excellent COX-2 activity, with IC50s ranging from 0.003 (7f,n) to 0.87 (7o) microM. In addition, most analogs of 7 showed no activity (IC50 > 100 microM) against the COX-1 enzyme. Replacement of the methyl sulfone moiety with a sulfonamide group gave a slightly more potent (typically 2-5-fold) but less selective COX-2 inhibitor, mainly due to an increase (20- > 100-fold) in COX-1 activity. However, in vitro COX-1/COX-2 selectivity for the sulfonamides 8 could be increased in many cases by simply incorporating a substituent at the 3-position of the phenyl group. Furthermore, in vitro selectivity increased with the size and number of substituents, as demonstrated in the selectivity trend of 8k (8000) > 8j (1900) > 8i (500) > 8h (100). More importantly, the sulfonamide COX-2 inhibitors showed greatly enhanced oral activity in the rat model of established adjuvant-induced arthritis, with inhibition values of 79.0% (8a), 81.5% (8c), and 83.0% (8g) at 1 mg/kg. On the basis of its overall biological profile, sulfonamide 8c was evaluated as a potential clinical candidate, displaying an ED50 of 22 mpk in the rat carrageenan-induced paw edema model and an ED50 of 0.16 mpk in the rat established adjuvant-induced arthritis model with no indication of gastrointestinal toxicity in rats and mice at 200 mpk. In addition, a preparative-scale synthetic route to sulfonamide 8c has been developed.
D000284:Administration, Oral; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000138:chemical synthesis / Q000494:pharmacology*; D001169:Arthritis, Experimental / Q000188:drug therapy; D016861:Cyclooxygenase Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology*; D003517:Cyclopentanes / Q000138:chemical synthesis / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy; D007213:Indomethacin / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051379:Mice; D015394:Molecular Structure; D051381:Rats; D011917:Rats, Inbred Lew; D017207:Rats, Sprague-Dawley; D013449:Sulfonamides / Q000138:chemical synthesis / Q000494:pharmacology*; D013450:Sulfones / Q000138:chemical synthesis / Q000494:pharmacology*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016861:Cyclooxygenase Inhibitors; D003517:Cyclopentanes; D013449:Sulfonamides; D013450:Sulfones; D007213:Indomethacin