Non‐Steroidal Anti‐inflammatory Agents: Novel Pyrazolyl‐, 1,2‐Oxazolyl‐, and 1,3‐Diazinyl Derivatives of 4(3H)‐Quinazolinones

Four novel series of 4(3H)-quinazolinone derivatives have been prepared by cyclization of the key intermediates 3-aryl-2-(3-aryl-3-oxopropenyl)-4-(3H)-quinazolinones with different reagents: 3-aryl-1-iminocarbamoyl-1H-pyrazol-5-yl)-4(3H)-quinazolines, 3-aryl-2-(3-aryl-1-thiocarbamoyl-1H-pyrazol-5-yl)-4(3H)-quinazolines, 3-aryl-2-(3-aryl-4,5-dihydro-1,2-oxazol-5-yl)-4(3H)-quinazolinones , and 3-aryl-2-(4-aryl-2-thioxo-1,2,5,6-tetrahydro-1,3-diazin-6-yl )-4(3H)- quinazolinones. The antiinflammatory activity of representatives of these compounds is comparable to or higher than that of proquazone.