Non‐Steroidal Antiinflammatory Agents Synthesis of Novel 2‐Pyrazolyl‐4(3 H )‐Quinazolinones

Four novel series of pyrazolyl‐4(3 H )‐quinazolinones have been prepared through the reaction of 3‐aryl‐2‐hydrazino‐4(3 H )‐quinazolinones with antipyrylazo‐derivatives of ethyl acetoacetate, acetylacetone or diethyl malonate. These series of compound are 3‐aryl‐2‐[1‐ethoxycarbonyl‐1‐(1,5‐dimethyl‐3‐oxo‐2‐phenyl‐2,3‐dihydro‐1 H ‐pyrazol‐4‐yl)hydrazono‐2‐propylidene]hydrazino‐4(3 H )‐quinazolinones;3‐aryl‐2‐[4‐(4,5‐dimethyl‐3‐oxo‐2‐phenyl‐2,3‐dihydro‐1 H ‐pyrazol‐4‐yl)hydrazono‐3‐methyl‐5‐oxo‐4,5‐dihydro‐1 H ‐pyrazol‐1‐yl]‐4(3 H ) ‐quinazolinones; 3‐aryl‐2‐[4‐(1,5‐dimethyl‐3‐oxo‐2‐phenyl‐2,3‐dihydro‐1 H ‐pyrazol‐4‐yl)azo‐3,5‐dimethyl‐1 H ‐pyrazol‐1‐yl]‐4(3 H )‐quinazolinones and 3‐aryl‐2‐[4‐(1,5‐dimethyl‐3‐oxo‐2‐phenyl‐2,3‐dihydro‐1 H ‐pyrazol‐4‐yl)hydrazono‐3,5‐dioxo‐pyrazolidin‐2‐yl]‐4(3 H )‐quinazolinones. The antiinflammatory activity of some representatives of the prepared compounds was studied.