SYNTHESIS AND EVALUATION OF CHALCONE-BASED 1,3,4- OXADIZOLE DERIVATIVES AGAINST ANTIINFLAMMATORY ACTIVITY

Chalcones are naturally occurring compounds widely distributed in plants and serve as important intermediates for the synthesis of various biologically active heterocyclic derivatives. In the present study, a new series of (E)-2-(1,3-diphenylallyl)-5-phenyl-1,3,4oxadiazole derivatives was synthesized and characterized by IR, ^1H NMR, and mass spectrometry. The synthesized compounds were evaluated for their acute toxicity, in vivo antiinflammatory activity, and in vitro antioxidant activity. Acute toxicity studies revealed that all compounds were free from toxic effects up to a dose of 1000 mg/kg body weight. The antiinflammatory activity was assessed using the carrageenan-induced rat paw edema model, with indomethacin serving as the standard reference. Among the synthesized derivatives, compound VII-c (X = 3-Cl-Benzaldehyde) exhibited the most potent anti-inflammatory activity, showing 89.8% inhibition of paw edema at the 4th hour. Antioxidant activity was determined using the DPPH free radical scavenging assay, where compounds VII-c and VII-e demonstrated significant radical scavenging potential with IC₅₀ values of 53.5 µM and 41.3 µM, respectively. The results suggest that the synthesized chalcone-based oxadiazole derivatives possess promising anti-inflammatory and antioxidant activities, indicating potential for further pharmacological development.