The new dibasic tetradentate (ONNO) Schiff base ligands (L₁and L₂) have been synthesized by the reaction of terephthalaldehyde with 2-amino 4-chlorophenol and X (where, X=2-amino 4-methylphenol, 2-aminophenol) in 1:1:1 molar ratio. The macrocyclic binuclear Co(II), Ni(II) and Cu((II) metal complexes are prepared in ligand to metal ratio 2:2. The elements, metal structure and binding sites of Schiff bases and its complexes are established by diverse studies like elemental, molar conductance, UV, magnetic moment, FT-IR, H¹ and C¹³ NMR, ESI-mass, ESR, thermal and powder-XRD. The spectral studies reveal that the ligands are tetradentate and its metal complexes possess a square planar geometry. All the compounds are screened for antibacterial, antioxidant and DNA cleavage and the results show high activity for metal complexes than the ligand. The DNA binding studies of Cu(II) complexes were measured by electronic absorption method. In vitro cytotoxicity assay of Cu(II) complexes have been tested for their tumour inhibiting potential against MCF-7 human breast cancer cell by using MTT method.

中文翻译：

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苯-1,4-二甲醛衍生的ONNO四齿席夫碱金属(II)配合物的合成、光谱解析、抗菌、抗氧化和DNA研究

通过对苯二醛与 2-氨基 4-氯苯酚和 X（其中，X=2-氨基 4-甲基苯酚、2-氨基苯酚）反应合成了新的二元四齿 (ONNO) 席夫碱配体（L ₁和 L ₂）摩尔比为 1:1:1。大环双核 Co(II)、Ni(II) 和 Cu(II) 金属配合物以配体与金属比 2:2 制备。席夫碱及其配合物的元素、金属结构和结合位点是通过多种研究确定的如元素、摩尔电导、紫外线、磁矩、FT-IR、H ¹和 C ¹³NMR、ESI-质量、ESR、热和粉末-XRD。光谱研究表明配体是四齿的，其金属配合物具有方形平面几何形状。所有化合物都经过抗菌、抗氧化和 DNA 切割的筛选，结果表明对金属配合物的活性高于配体。Cu(II)配合物的DNA结合研究是通过电子吸收法测量的。已通过使用 MTT 方法测试了 Cu(II) 复合物的体外细胞毒性测定对 MCF-7 人乳腺癌细胞的肿瘤抑制潜力。