Synthesis of 3-[4[4,5-dihydro-5-(substituted aryl)-1H-pyrazol-3-yl]phenyl]sydnones as antiinflammatory and analgesic agents

3-[4-(3-(Substituted aryl)-1-oxo-2-propenyl]phenyl]sydnones were condensed with hydrazine to yield fifteen 3-[4-(4,5-Dihydro-5-(substituted aryl)-1H-pyrazol-3-yl]phenyl]sydnones. Three compounds have shown antiinflammatory activity in carrageenan induced edema assay in rats and five compounds have shown analgesic activity. In acetic acid-induced writhing assay in mice at 100 mg/kg dose p.o. respectively. Compound 24 exhibited both antiinflammatory and analgesic activity, which appeared to be similar to those produced by the standards phenylbutazone and aspirin. However compound 21 showed more analgesic activity than aspirin (ED 50, 25.0mg/kg, 81.4mg/kg).