Synthesis and cyclooxygenase inhibitory activities of some N-acylhydrazone derivatives of isoxazolo[4,5-d]pyridazin-4(5H)-ones.

In this study, new isoxazolo[4,5-d]pyridazin-4(5H)-one derivatives having an N-acylhydrazone moiety were synthesized. The compounds were tested for their COX inhibitory activities using NS-398 and indomethacine as reference compounds. Although the compounds had an inhibitory profile against both COX-1 and COX-2, most were found to be more selective against COX-2 by a small percentage of inhibition, at the concentration of 50 microM.