使用邻苯二胺和取代的水杨醛，然后通过两步反应方法合成了三种新的ONNO-供体四齿不对称salen配体。这三种配体与 Cu(OAc)2.4H2O 反应生成三种新的单体 Cu(II) 配合物 [CuII(L1-3)] (1-3)。使用元素分析、IR、UV-vis、NMR 和 HR-ESI-MS 技术来分析和表征所有合成的配体及其相应的金属配合物。通过单晶-XRD分析证实了1-3的分子结构。此外，还通过紫外-可见光、荧光光谱以及圆二色性研究检查了这些复合物的 DNA 结合能力。所有复合物均显示出嵌入结合模式，Kb 值在 104-105 M-1 范围内。最后，1-3 针对两种恶性（HeLa 和 A549）和非癌（NIH-3T3）细胞系进行了测试，以检查其体外抗增殖活性。其中，1 是该系列中最具细胞毒性的，对 HeLa 和 A549 细胞系的 IC50 值分别为 5.7 ± 0.9 和 6.0 ± 0.3 μM。这个结果也与DNA结合顺序一致。此外，还通过DAPI、AO/EB和Annexin V-FITC/PI双染色测定评估了所有复合物的细胞死亡模式。版权所有©2024 Elsevier Inc.保留所有权利。

Three new ONNO-donor tetradentate unsymmetrical salen ligands were synthesized by using o-phenyl diamine with substituted salicylaldehydes followed by a two-step reaction methodology. These three ligands by reaction with Cu(OAc)2.4H2O produced three new monomeric Cu(II) complexes, [CuII(L1-3)] (1-3). Elemental analysis, IR, UV-vis, NMR, and HR-ESI-MS techniques were used to analyze and characterize all the synthesized ligands and their corresponding metal complexes. Molecular structures of 1-3 were confirmed by the single-crystal-XRD analysis. Furthermore, the DNA binding ability of these complexes was checked through UV-vis, fluorescence spectroscopy, and also by circular dichroism studies. All the complexes were found to show an intercalation mode of binding with the Kb value in the range of 104-105 M-1. Finally, 1-3 was tested against two malignant (HeLa and A549) and non-cancerous (NIH-3T3) cell lines to check their in vitro antiproliferative activities. Among all, 1 is the most cytotoxic of the series having IC50 values of 5.7 ± 0.9 and 6.0 ± 0.3 μM against HeLa and A549 cell lines, respectively. This result is also consistent with the DNA binding order. Furthermore, the apoptotic mode of cell death of all the complexes was also evaluated by DAPI, AO/EB, and Annexin V-FITC/PI double staining assays.Copyright © 2024 Elsevier Inc. All rights reserved.