SYNTHESIS OF 4-[5-(SUBSTITUTED YL)-4,5-DIHYDRO-1H-PYRAZOL-3-YL]-3-PHENYL-SYDNONES AS ANTIINFLAMMATORY, ANTIARTHRITIC AND ANALGESIC AGENTS

4-[1-Oxo-3-(substituted aryl)-2-propenyl]-3-phenylsydnones were conden sed with hydrazine to yield fourteen 4-[5-(substituted yl)-4,5-dihydro -1H-pyrazol-3-yl]-3-phenylsydnones. Four compounds have shown antiinfl ammatory activity in carrageenen-induced edema assay in rats and six c ompounds have shown analgesic activity in acetic-acid-induced writhing assay in mice at a dosage of 100 mg/kg po. The antiinflammatory activ ity of these compounds was less than the positive controls phenylbutaz one and ibuprofen. However, compound 25 has shown more analgesic activ ity than aspirin (ED(50), 28.3 vs 81.4 mg/kg respectively, po). Two co mpounds have shown antiarthritic activity in adjuvant-induced arthriti s in rats. The ulcerogenicity of active compounds was less than phenyl butazone.