Synthesis and evaluation of anti-inflammatory and antimicrobial activity of 2,5-disubstituted-1,3,4-oxadiazoles

In the present study two new series of [5-(4-substituted-phenyl)-[1,3,4]oxadiazol-2-yl]-pyridine (1a-1d) and 2-(4-substituted phenyl)-5-(2-aminophenyl)-1,3,4-oxadiazole (2a-2e) were synthesized from esters and hydrazine hydrate in the presence of ethanol through isonicotinic acid hydrazide and 2-aminobenzohydrazide respectively followed by reaction with phosphorus oxychloride and various aromatic acids. Synthesized compounds were subjected to antiinflammatory and antimicrobial activity. A fair number of compounds were found to have good anti-inflammatory activity in carrageenan-induced rat paw oedema test, while all the compounds showed significant antibacterial activity.