中文摘要：

为发现氟喹诺酮由抗菌活性到抗肿瘤活性转化的有效结构修饰策略,以均三唑硫醇（酮）杂环为C-3羧基的等排体,经硫醚化修饰得C-3均三唑硫醚酮（6a～6g）,进一步优化得C-3均三唑硫醚酮缩氨基硫脲（7a～7g）和C-3噻唑并三唑稠杂环类（8a～8g）。用元素分析和光谱数据确证化合物的结构,用MTT方法评价3类化合物对Hep-3B、Capan-1和HL60的体外抗增值活性。结果表明,上述3类化合物的体外抗肿瘤活性均强于环丙沙星,其中相应化合物的活性次序为7〉8〉6,对肿瘤细胞的选择性为Capan-1〉Hep-3B〉HL60。同时,含吸电子基（F、NO2）取代的目标化合物（6f、7f、8f和6g、7g、8g）均强于其他取代基目标物的活性,尤其是缩氨基硫脲类（7f、7g）对Capan-1的IC50值与对照药多柔比星相当。为此,硫醚酮缩氨基硫脲修饰的均三唑杂环作为C-3羧基等排体值得关注和进一步发展。

英文摘要：

To discover an efficient strategy for the conversion of the antibacterial activity of fluoroquinolones into the antitumor activity, the three series of C-3 s-triazole-based derivatives including sulfide ketones （6a-6g）, thiosemiearbazones （Ta-Tg） and fused heterocyclic thiazolotriazoles （8a-8g） were synthesized from ciprofloxacin （1）, respectively. The structures were characterized by elemental analysis and spectral data. The antitumor activity was tested against three tumor cell lines （Hep-3B, Capan-1 and HL60） using the MTT assay. The three types of compounds all exhibited stronger anti-proliferative activities than ciprofloxacin in the test. The order of their activities was in compounds 7〉8〉6, and the order of selectivity against cancer cell lines was Capan-1, Hep-3B and HLf60. Meanwhile, the SAR revealed that some compounds with electron-drawing group substituted such as fluoro- and nitro-phenyl compounds （6f, 7f, 8f） and （6g, 7g, 8g） displayed more significant activity than the control compounds, especially the IC50 values of thiosemicarbazone compounds 7f and 7g against Capan-1 was comparable to doxorubicin. Thus, a five-membered triazole as the C-3 bioisostere modified with thefunctionalized side-chain of sulfide-ketone thiosemicarbazone warrants special attention and further investigation.