Abstract Here, we present a new polymorph of the [Cu(5mebipy)(NO3)]NO3 complex (1, Form II), where 5mebipy means 5,5′-dimethyl-2,2′-bipyridine. The copper(II) complex 1 was characterized by spectroscopic techniques and single-crystal X-ray diffraction. The Form II presents a six-coordinated structure, meanwhile the Form I, previously reported, is five-coordinated with the nitrate ligand as monodentate. The molecular structures of both crystalline forms were compared based on intramolecular aspects using Kleywegt's analysis and the intermolecular contacts evaluated by Hirshfeld surface studies. Moreover, the interaction of the complex [Cu(5mebipy)(NO3)]+ with CT-DNA was carried out using viscosity and spectrophotometric titrations, exhibiting a binding constant of 2.57 × 104 M − 1. This study contributes to explore the intra and intermolecular details of the new polymorph of the complex [Cu(5mebipy)(NO3)]NO3 and its capability to interacts with CT-DNA.

中文翻译：

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六配位双(5,5'-二甲基-2,2'-联吡啶)硝基铜(II)的新多晶型及其DNA相互作用

摘要 在这里，我们提出了 [Cu(5mebipy)(NO3)]NO3 复合物（1，形式 II）的新多晶型物，其中 5mebipy 表示 5,5'-二甲基-2,2'-联吡啶。铜 (II) 配合物 1 通过光谱技术和单晶 X 射线衍射表征。形式 II 呈现六配位结构，而先前报道的形式 I 与硝酸盐配体五配位，作为单齿。使用 Kleywegt 的分析和由 Hirshfeld 表面研究评估的分子间接触，基于分子内方面比较两种结晶形式的分子结构。此外，复合物 [Cu(5mebipy)(NO3)]+ 与 CT-DNA 的相互作用是使用粘度和分光光度滴定法进行的，结合常数为 2.57 × 104 M - 1。