Quinazolino-thiadiazoles as antimicrobial agents

Abstract

In the present research, we report the synthesis and in vitro antimicrobial activity of a new series of novel quinazolino-thiadiazoles as fused pharmacophore (3–20). In general, the results of the in vitro antibacterial activity are encouraging, as out of 18 compounds tested, Compounds 3 and 8 with a 4-chlorophenyl and 4-nitro phenyl at C-2 of thiadiazole and chloromethyl substituent at C-2 of quinazolinone displayed a broad spectrum antimicrobial activity against all the strains, while compounds 13 and 16 again with a 4-chlorophenyl and 4-nitrophenyl at C-2 of thiadiazole and ethyl substituent at C-2 of quinazolinone showed the same potency but with a narrower spectrum (Bacterial and Fungal strains) with MIC values of 62.5 µg/ml. The structures of the compounds were confirmed by IR, ¹H NMR, ¹³C NMR and Mass analysis. It is worth to mention that the combination of two biologically active moieties quinazoline and thiadiazole profoundly influences the biological activity.