Quinolone Structure-activity Relationship Study

The quinolone antibacterial agents are widely used in the clinical field because of their excellent antibacterial activity, wide spectrum, and high bioavailability. Recently, several kinds of the quinolone antibacterial, such as ciprofloxacin, sparfloxacin, and ofloxacin, have been examined as inhibitors of tuberculosis infection and a series of new quinolone derivatives exhibit fairly good anti-HIV activity. In view of the importance of structure-activity relationships (SARs) studies, the major efforts in this paper have been performed on SARs of quinolone, the main results can be split to four parts and summarized as follows: Firstly, structure-activity relationships of the quinolone antibacterial agents which were paid less attention to before, have been investigated: 1. Antibacterial activities are closely related to the steric conformation and distribution of electrostatic potential of carboxyl group: the coplanatity of C-3 group, C-4 group and the quinolone ring is very important for antibacterial activities. It is also significant that two oxygen atoms of C-3carboxyl (or the part of simulating carboxylic acid) have strongly negative electrostatic potential at the plane of quinolone ring. 2. Quantitative structure-activity relationships (QSARs) of 1 -methyl-6-difluoro-7-substituted-quinolones are investigated. The results show...