Synthesis and antibacterial activity of novel quinoxalinone derivatives

Abstract

The reaction of 3-hydrazinocarbonylmethylquinoxalin-2(1H)-one with phthalic anhydride, certain aromatic aldehydes, isocyanates and phenyl isothiocyanate furnished corresponding imide, Schiff's, semi- and thiosemicabazide derivatives. Treatment of 3-[2 (phenylcarbamoyl)hydrazinocarbonylmethyl]quinoxalin-2(1H)-one with chloroacetic acid, sulfuric acid and sodium hydroxide yielded cyclised derivatives. Moreover, 3-[2-bromobenzylidenehydrazinocarbonyl-methyl]quinoxalin- 2(1H)-one was cyclised to oxadiazolinyl derivative using acetic anhydride. Furthermore, 3-[5-sulfanylidene-4,5-dihydro-1,3,4-oxadiazol-2-yl)methyl] quinoxalin-2(1H)-one was employed as a precursor in the synthesis of some novel 2(1H)-quinoxalinones. Some of the newly prepared compounds were evaluated for in vitro antibacterial activity using ofloxacin as the reference standard.