利用量子化学半经验分子轨道ＡＭ１方法对喹啉、萘啶、吡啶［２，３Ｃ］哒嗪环系的系列化合物进行了定量构效关系研究，建立了很好的ＱＳＡＲ方程。结果表明：喹诺酮３位羧基与母核的共平面性对生物活性有重要的影响；４位酮基上氧的净电荷与生物活性有一致性关系。设计了１个生物活性很高的、新母核的异噻唑骈吡啶酮类化合物 Quantum structure-activity relationship of a series of compounds of quinoline, naphthyridine, pyrido [2,3-c] pyridazine ring system was studied by AM1 quantum chemical semi-empirical molecular orbitals, and a good QSAR equation was established. The results showed that the co-planarity of the carboxy group and the mother nucleus of quinolone had an important effect on the biological activity. The net charge of the oxygen on the 4-keto group was consistent with the biological activity. A novel biologically active isothiazolopyridinone compound was designed