Design, Synthesis and Antibacterial Activity of some 3,6-Dimethlyquinoxaline-2-Hydrazone Derivatives

Aims: This aims of this study was to continue the effort to synthesis new quinoxaline-based heterocycles and study its antibacterial properties. Objective: This study was designed to reacts 3,6-dimethylquinoxaline-2-hydrazine with some substituted aromatic ketones and study their antibacterial properties on some locally and clinically isolated bacterial strains. Materials and Methods: Five 3,6-dimethylquinoxaline-2-hydrazone derivatives were synthesized from the reactions of 3,6-dimethylquinoxaline-2-hydrazine with various substituted aromatic ketones. The products were then tested for their potential antibacterial properties. Results: All the synthesized compounds were found to be active against all the bacterial strains investigated in this study. It was observed that the zones of inhibition observed for the synthesized compounds against the test organisms ranged between 15 mm and 38 mm. The MIC observed for the synthesized compounds ranged between 0.0313mg/mL and 0.125 mg/mL, while that of the standard antibiotic, streptomycin, varied between 0.0313 mg/mL and 0.500 mg/mL and those observed for tetracycline falls between 0.0313 mg/mL and 0.500 mg/mL. The minimum bactericidal concentrations exhibited by the synthesized compounds ranged between 0.0625 mg/mL and 0.250 mg/mL Discussion and conclusion: The study concluded that all the compounds exhibited appreciable bactericidal effects against all the bacterial strains, which is an indication that such synthetic compounds possessed broad spectrum activities and such compounds could be useful in formulation of antibacterial compounds which could be used to mitigates infections caused by pathogens that are now developing resistance against the available antibiotics.