In this work, mixed ligand complexes of Co(II) Ni(II) and Cu(II) were synthesized using quercetin and diimine (1,10-phenanthroline or 2,2′-bipyiridine) ligands. The obtained Ni(II) and Co(II) complexes are new and the Cu(II) complexes are synthesized by different method from the literature. The characterization of complexes was performed by elemental analysis, thermogravimetric analysis, ESI–MS, UV–visible and infrared spectral analyses, magnetic susceptibility and molar conductivity measurements. It was found that quercetin, diimine and metal(II) ion form 1:1:1 complexes. Resulting data supported octahedral geometry for Ni(II) and Co(II) complexes and square pyramidal geometry for Cu(II) complexes. The proposed compositions are [Co(queH-1)Cl(phen)(H₂O)]∙2H₂O (1, queH = quercetin, phen = 1,10-phenanthroline), [Ni(queH-1)Cl(phen)(H₂O)]∙2H₂O (2), [Cu(queH-1)Cl(phen)]∙2.5H₂O (3) and [Cu(queH-1)Cl(bpy)]∙2H₂O (4, bpy = 2,2′-bipyiridine). Antioxidant capacity and total phenolic content of complexes measured by Folin–Ciocalteu and ABTS methods. Anti-cancer effect of these compounds were tested against different cancer cells (A549, PC-3, HeLa and MCF-7). Apoptosis identified by the fluorescence imaging, caspase cleaved cytokeratin-18 and flow cytometry analysis (annexin V, caspase 3/7, mitochondria membrane potential and oxidative stress). As a result, Cu(II) complexes are more effective than the other compounds and Complex 3 is a promising anti-cancer compound against breast cancer MCF-7 and MDA-MB-231 cells (IC₅₀ values are 2.4 and 5.4 µM for 48 h, respectively). Flow cytometry analysis exhibited that Complex 3 caused apoptosis in MCF-7 cells. These results support that Complex 3 has anticancer activity and can be a potential anticancer agent especially in breast cancer.

中文翻译：

---

Co（II），Ni（II）和Cu（II）与槲皮素和二亚胺配体的混合配体配合物：合成，表征，抗癌和抗氧化活性。

在这项工作中，使用槲皮素和二亚胺（1,10-菲咯啉或2,2'-联吡啶）配体合成了Co（II）Ni（II）和Cu（II）的混合配体配合物。所获得的Ni（II）和Co（II）配合物是新的，并且Cu（II）配合物是通过与文献不同的方法合成的。通过元素分析，热重分析，ESI-MS，紫外-可见和红外光谱分析，磁化率和摩尔电导率测量来进行复合物的表征。发现槲皮素，二亚胺和金属（II）离子形成1：1：1的配合物。所得数据支持Ni（II）和Co（II）配合物的八面体几何形状以及Cu（II）配合物的方锥几何形状。提议的组成为[Co（queH-1）Cl（phen）（H ₂ O）]∙2H ₂ O（1，queH =槲皮素，phen = 1,10-菲咯啉），[Ni（queH-1）Cl（phen）（H ₂ O）]∙2H ₂ O（2），[Cu（queH-1）Cl（phen） ]∙2.5H ₂ O（3）和[Cu（queH-1）Cl（bpy）]∙2H ₂ O（4，bpy = 2,2'-联吡啶）。通过Folin - Ciocalteu和ABTS方法测量复合物的抗氧化能力和总酚含量。测试了这些化合物对不同癌细胞（A549，PC-3，HeLa和MCF-7）的抗癌作用。通过荧光成像鉴定凋亡，胱天蛋白酶裂解细胞角蛋白-18和流式细胞仪分析（annexin V，caspase 3/7，线粒体膜电位和氧化应激）。其结果是，铜（II）复合物比其它化合物更有效和更复杂3是一种很有前途的抗-抗乳腺癌MCF-7和MDA-MB-231细胞（IC癌症化合物₅₀ 值是2.4和5.4μM48 h分别）。流式细胞仪分析表明复合物3导致MCF-7细胞凋亡。这些结果支持复合物3具有抗癌活性，并且可以是潜在的抗癌剂，尤其是在乳腺癌中。