Synthesis and amelioration of inflammatory paw edema by novel benzophenone appended oxadiazole derivatives by exhibiting cyclooxygenase-2 antagonist activity.

Ten new 2(4-hydroxy-3-benzoyl) benzamide-5-phenyl-1,3,4-oxadiazole derivatives (10a-j) were synthesized by coupling 3-benzoyl-4-hydroxybenzoic acid (5) with 2-amino-5-phenyl-1,3,4-oxadiazoles (9a-j). The structures of these compounds were confirmed by IR, 1H, 13C NMR, and mass spectra, and also by elemental analyses. The anti-inflammatory activity of the compounds 10a-j were investigated by screening them against human red blood cells (HRBC) in-vitro. The results reveal that among this series, compound 10j with hydroxy substituent, particularly at the ortho position of the phenyl ring attached to the 5th carbon atom of the oxadiazole ring possess significant membrane stabilizing activity in comparison with the control. Further, in-vivo chick chorioallantoic membrane (CAM) and rat corneal anti-angiogenesis assays were performed to assess the effect of compound 10j on endothelial cell migration. This confirmed that compound 10j inhibits the proliferation of endothelial cells. Anti-inflammatory studies detected the amelioration of carrageen induced rat hind paw edema. Further in-vivo and in-silico approaches revealed the inhibition of inflammatory marker enzyme cyclooxygenase-2 (Cox-2) and myleoperoxidase (MPO). The study reports that the compound 10j effectively act against the inflammatory mediated anti-angiogenic disorders which could be translated into a new drug in future.