Synthesis and Biological Evaluation of the Pyrazole Class of Cyclooxygenase- 2-Inhibitors

Several 1,3,4-trisubstituted pyrazole derivatives were synthesized via condensation with the appropriate amine, sulphonamide, acid hydrazide, or benzyl thiosemicarbazide derivatives. The newly synthesized compounds were screened for a possible anti-inflammatory effect in a rat model of air-pouch carrageenan-induced inflammation. The results revealed that some of the newly synthesized compounds exhibited a significant anti-inflammatory effect in terms of reducing exudation and/or leukocytic accumulation at the site of inflammation. Thus, compared to carrageenan-induced inflammation group, compounds 3, 9, 13, and 17 were particularly associated with significant decrease in both the volume of exudate and leukocyte accumulation while compounds 4, 7, 10, 11 and 15 were associated with significant decrease in the volume of inflammatory exudate without a corresponding decrease in the number of accumulated leukocytes. Moreover, a docked pose of compound 17 was obtained and bound to cyclooxygenase active site of COX-2 using Molecular Operating Environment (MOE) module.