喹诺酮类药物是两类重要抗生素之一，此类化合物的结构见图１。虽然喹诺酮不同位置的结构修饰已涌现出许多广谱、高效、低毒性的化疗药物，如诺氟沙星、环丙沙星、氧氟沙星等［１］。但对Ｃ－４位的修饰却未能成功：Ｃ－４位酮基被硫酮基、亚胺基取代均使活性消失［２］；... Quinolones are one of two important classes of antibiotics. The structure of these compounds is shown in Figure 1. Although the structural modification of different positions of quinolones has emerged a number of broad-spectrum, high-efficiency, low toxicity chemotherapy drugs, such as norfloxacin, ciprofloxacin, ofloxacin [1]. However, the modification of C-4 was unsuccessful: the keto group at C-4 was completely destroyed by thioketone or imine substitution [2];