The aim of this study was to design, synthesize, and investigate the in vivo anti-inß ammatory activity of some novel 2, 5-disubstituted - 1, 3, 4-oxadiazole derivatives. Ethyl-4-acetamido phenoxy acetate (I) was prepared by the condensation of ethyl chloroacetate with starting material p-acetamidophenol in the presence of dry acetone and anhydrous potassium carbonate. Hydrazinolysis of (I) with hydrazine hydrate results in the formation of 4-acetamidophenoxy acetyl hydrazide (II), which on cyclisation with various substituted aromatic carboxylic acids in the presence of phosphorous oxychloride affords various 2, 5-disubstituted - 1, 3, 4-oxadiazole derivatives (IIIa-IIIi). The newly synthesized compounds were characterized by IR, 1HNMR, and MS spectral data. The titled compounds were screened for in vivo anti- inß ammatory activity using the carrageenan-induced paw edema method. A few of them manifested promising activity when compared with the standard drug Diclofenac sodium.
Key words: Anti-inß ammatory activity, 1, 3, 4 - oxadiazoles, Ethyl - 4- acetamido phenoxy acetate, 4 - acetamido phenoxy acetyl hydrazide.