In this study, a series of carbazole-rhodanine conjugates was synthesized and evaluated for their Topoisomerase II inhibition potency as well as cytotoxicity against a panel of four human cancer cell lines. Among these thirteen compounds, 3a, 3b, 3g, and 3h possessed Topoisomerase II inhibition potency at 20 μM. Mechanism study revealed that these compounds may function as Topo II catalytic inhibitors. It was found that the electron-withdrawing groups on the phenyl ring of compounds played an important role on enhancing both enzyme inhibition and cytotoxicity.

中文翻译：

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新型咔唑-若丹宁偶联物作为拓扑异构酶II抑制剂的合成及生物学评价

在这项研究中，合成了一系列咔唑-罗丹宁偶联物，并评估了它们对拓扑异构酶II的抑制能力以及对一组四种人类癌细胞系的细胞毒性。在这13种化合物中，3a，3b，3g和3h在20μM时具有Topoisomerase II抑制能力。机理研究表明，这些化合物可能充当Topo II催化抑制剂。发现化合物苯环上的吸电子基团在增强酶抑制和细胞毒性方面都起着重要作用。