Abstract
magnified image The Gould‐Jacob type of reaction for the synthesis of ethyl 5‐ethyl‐8‐oxo‐5,8‐dihydro‐[1,3]‐dioxolo[4,5‐g]quinoline‐7‐carboxylate 4 has been carried out conventionally by the condensation between N‐ethyl‐3,4‐methylenedioxyaniline 1 and diethyl ethoxymethylenemalonate 2 gave the unsaturated ester 3 and thermal cyclization in refluxing diphenyl oxide gave quinolone ethyl ester 4 and the results obtained were compared with single step microwave irradiation under solvent free conditions for the synthesis of 4. The esters on basic hydrolysis formed free acid 5, which, upon treatment with thionyl chloride gave the acid chloride 6. Treatment of acid chloride with o‐phenylenediamine, hydrazine hydrate, ammonia, urea, and thiourea gave the amides (7, 8, 9, 10, 11). CS~2~ treatment in presence of KOH on 8 gave 12. We prepared 7, 8, 9, 10, 11, 12 derivatives by conventional as well as microwave irradiation. These compounds have been characterized on the basis of IR, ^1^H NMR, MS, and elemental analysis. All the compounds prepared herein were screened for their antibacterial activity. Compounds 4, 5 possess promising antibacterial activity and compound 8 showed significant antibacterial activity. J. Heterocyclic Chem., (2010).