or unsubstituted 1-piperazinyl groups were introduced as the C-7 variants. As a result of this study, 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1, 8-naphthyridine-3-carboxylic acid (named enoxacin, originally AT-2266) was found to show the most broad and potent in vitro antibacterial activity, an excellent in vivo efficacy on systemic infections, and a weak acute toxicity. Structure-activity
制备具有硝基,
氨基,
氰基,
氯或
氟作为C-6取代基的标题化合物。通过6-
氨基-
1,8-萘啶衍
生物9经由其6-重氮盐的Sandmeyer反应,在C-6处引入
氯基和
氰基。反应扩展到6-
氟类似物的合成,涉及四
氟硼酸重氮鎓的Balz-Schiemann反应。此外,一系列7-取代的6-
氟-1,4-
氟-1,4-二氢-4-氧代-1,8的1-乙基,
1-乙烯基,1-(2-
氟乙基)和1-(二
氟甲基)类似物制备了
萘啶-3-
羧酸。引入1-
吡咯烷基,特别是N-取代或未取代的1-
哌嗪基作为C-7变体。这项研究的结果是1-乙基-6-
氟-1,4-二氢-4-氧代-7-(1-
哌嗪基)-1 发现8-
萘啶-3-
羧酸(命名为
依诺沙星,最初为AT-2266)具有最广泛和有效的体外抗菌活性,对全身感染的体内疗效极佳,并且急性毒性也较弱。还讨论了在C-1,C-6和C-7处具有取代基变化的化合物的结构活性关系。