Synthesize The Efflux Pump Inhibitors Of Resistant Bacterial And Evaluate Their Antibacterial Activity

Bacterial resistance is an increasingly serious problem which threatening the human and animals. Research shows that efflux pump of bacterial is an important mechanism of the resistance. Efflux pump which exists on the intracellular membrane of drug-resistant strains can decrease the effective concentration inside of bacterial by pump out drug from cells. Inhibitor of efflux pump has no effective antibacterial activity itself. But it could reverse the drug resistance by inhibiting the efflux pump. So the research and development of efflux pump inhibitor may become an important way to solve the problem of bacterial resistance. In this dissertation, the analogues of known efflux pump inhibitors were designed and synthesized and their antimicrobial activity were evaluated. The salicylanilide analogues which possess antibacterial activity were also synthesized.In the Chapter Two, a new flavone was synthesized from quercetin and isoeugenol and characterized by MS and 1HNMR. Nine 2,6-dimethyl-4-arylpyridine-3,5-dicarboxylic acid diethyl esters were synthesized and characterized. The reaction conditions were optimizing by choosing suitable solvent and catalyst. The synthesis of 2-aryl-5-nitro-lH-indoles was explored use aromatic ketones and 4-Nitrophenylhydrazine as starting material. The synthesis of salicylanilide analogues was explored in the Chapter Three.In the Chapter Four, the antimicrobial activity of some synthetic compounds combined with antibacterial drugs was evaluated. Inhibition zone and minimal inhibitory concentration were used as evaluation criterion. The mixture of Ciprofloxacin and any one of these compounds can lower the minimal inhibitory concentration of Ciprofloxacin in drug resistant strains, therefore they can inhibit the drug resistant strains of Staphylococcus aureus effectively.