SYNTHESIS OF QUINAZOLINONE DERIVATIVES AND THEIR ANTIMICROBIAL EVALUATION

Some new series of 3-(4-substituted-phenyl)-2-thioxo-2,3-dihydroquinazolin4(1H)-one, 3-(4-substituted-phenyl)-2-(methylthio) quinazolin-4(3H)-one and 3-(4-substituted-phenyl)-2-hydrazinylquinazolin-4(3H)-one were synthesized by cyclization of 4-substituted-phenylcarbamodithioate with methyl anthranilate followed by reaction with dimethylsulphate and then prepared compound was refluxed with hydrazinehydrate respectively. The starting material 4-substituted-phenylcarbamodithioate was synthesized from 4substituted-aniline. The title compounds were investigated for antibacterial and antifungal activity by disc diffusion technique. Compound IIa, IIb and IIIa showed moderate activity against B. subtilis, E. coli and A. niger as compared to standard drug. Compound IIIb and Iva exhibited good activity against A. niger. Compound IIIc and IVc was found to be most active compound against E. coli and moderately active against B. subtilis and A. niger, of the prepared series.