Synthesis and Biological Evaluation of 3-Amino Pyrazolones

Abstract

A series of 3-amino-4-(substituted benzylidene)-1H-pyrazol-5(4H)-ones were synthesized by condensation of ethyl-2-cyano-3-(substituted) phenylacrylates with hydrazine hydrate. The chemical structures of synthesized compounds were confirmed by means of IR, 1H NMR, mass spectral and elemental analysis. All the compounds were screened for their antiinflammatory, analgesic and antioxidant activities. Out of these compounds, 4-hydroxy-3,5-dimethoxy (24) and 4-dimethylamino (17) derivatives showed good antiinflammatory activity. 4-dimethylamino (17) and 5-bromo-4-hydroxy-3-methoxy (23) derivatives showed moderate analgesic activity.