AbstractThis study was the first to synthesize terpene‐containing conjugates of fluoroquinolones, ciprofloxacin and norfloxacin, and to evaluate their antibacterial activity against gram‐positive methicillin sensitive (MSSA) and methicillin resistant (MRSA) S. aureus, gram‐negative P. aeruginosa as well as antifungal activity against C. albicans. The ability of obtained fluoroquinolones to inhibit S. aureus growth was found to depend upon the presence of a linker separating the bulky terpene and fluoroquinolone fragments, and this activity diminished with increasing its length. The highest activity against MSSA was demonstrated by ciprofloxacin derivatives with campholenic (MIC 1 μg/mL) and 2‐(isobornan‐2‐yl‐sulfanyl)acetyl (MIC 0.5 μg/mL) substituents. The compound with the last fragment showed high activity against MRSA (MIC 8 μg/mL). The terpene‐functionalized norfloxacin derivatives generally proved to be less active than those containing ciprofloxacin fragment. Camphor‐10‐sulfonylamide derivative with the ciprofloxacin fragment was the only one of all compounds that showed high antifungal activity against C. albicans (8 μg/mL). The study presents data on docking fluoroquinolones to S. aureus DNA gyrase to explain the reasons for manifestation or disappearance of antibacterial activity. The cytotoxicity of fluoroquinolones that showed any antimicrobial activity was investigated against bovine primary lung cells, and they were found to be not toxic in most cases.
摘要 本研究首次合成了含萜烯的氟喹诺酮类药物环丙沙星和诺氟沙星共轭物,并评估了它们对革兰阳性甲氧西林敏感(MSSA)和甲氧西林耐药(MRSA)金黄色葡萄球菌、革兰阴性绿脓杆菌的抗菌活性,以及对白僵菌的抗真菌活性。研究发现,所获得的氟喹诺酮类药物抑制金黄色葡萄球菌生长的能力取决于是否存在将笨重的萜烯和氟喹诺酮片段分隔开来的连接体,这种活性随着连接体长度的增加而减弱。对金黄色葡萄球菌活性最高的是带有樟脑(MIC 1 μg/mL)和 2-(异龙脑-2-基硫基)乙酰(MIC 0.5 μg/mL)取代基的环丙沙星衍生物。带有最后一个片段的化合物对 MRSA 具有较高的活性(MIC 8 μg/mL)。事实证明,萜烯功能化的诺氟沙星衍生物的活性普遍低于含有环丙沙星片段的衍生物。含有环丙沙星片段的樟脑-10-磺酰胺衍生物是所有化合物中唯一对白茨球菌具有较高抗真菌活性的化合物(8 μg/mL)。该研究提供了氟喹诺酮类药物与金黄色葡萄球菌 DNA 回旋酶对接的数据,以解释抗菌活性显现或消失的原因。研究还调查了具有任何抗菌活性的氟喹诺酮类药物对牛原代肺细胞的细胞毒性,发现它们在大多数情况下没有毒性。