New Quinolone Compound Design, Synthesis And Antibacterial Activity

Quinolone antibacterial agents are the group of the most attractive drugs in the antiinfective chemotherapy field. A variety of quinolone antibacterials are of characters of strong anti-bacteria and wide spectrum. In this thesis, we have reviewed the recent advances in the studies on the composition, syntheses, structure-activity relationship, structural modification and pharmacology of quinolone, studied the methods of synthesizing and modifying quinolone, synthesized a series of new fluoroquinolone analogues as antibacterials.Recent researches are focused on the structural modification of 6, 7, 8 positions of quinolone and annex on 3 position, in order to obtain higher efficiency drugs.On the basis of above-mentioned studies, we designed and synthesized three quinolone analogues (compounds 1 to 3), Ciprofloxacin, Nofloxacin, Enrofloxacin, from the 2,4- dichloro - 5 - fluro - benzoic acid. Then, we obtained two series of new fluoroquinolone analogues (compounds 4 to 21) by reaction of compounds 1 and 2 with chloride of acid, chloro-carbonic ester. Finally, we gained four esterifiable quinolone analogues (compounds 22 to 25) by modifying the structures of compound 3, 14 and 16 on 3 position. And their structures were confirmed by IR, HNMR and elementary analysis.Bacterial activities of compounds 4 to 21 in vitro were tested. The activities of four compounds are higher than ciprofloxacin and nofloxacin.