We describe herein, synthesis of a half-sandwich Ru (II)(ƞ⁶-p-cymene) complex 1 containing aminoquinoline ligand. Complex 1 was characterized by various spectroscopic and single-crystal X-ray crystallographic techniques. The “piano-stool” complex crystallizes in a triclinic P$\overline{1}$ space group with ruthenium (Ⅱ)(p-cymene) fragment tethered to a primary amine nitrogen atom of aminoquinoline. DFT calculations were performed to generate UV and IR spectra of complex 1 which further supported the experimental data. Comparative DNA/RNA binding studies of the complex were carried out by employing UV–vis, fluorescence, circular dichroism, and cyclic voltammetric techniques. The intrinsic binding constants of the complex 1 with ct-DNA and tRNA were calculated to be 3.9 × 10⁵ (±0.09) M⁻¹ and 2.45 × 10⁴ (±0.10) M⁻¹ which indicated a stronger binding affinity of the complex 1 towards ct-DNA. The pBR322 plasmid scissoring efficiency of the complex was explored by performing gel electrophoresis. The results suggested that the complex induced double-stranded DNA cleavage at 35 μM concentration which is mediated via an oxidative pathway. RNA gel fragmentation assay was also performed in both concentration and time-dependent manner and an appreciable reduction in the intensity of the bands was observed after 24 hr incubation which demonstrated complete cleavage of the tRNA. BSA and lysozyme binding studies of the complex were also carried out and the results revealed that complex 1 quenched the fluorescence intensity of the proteins. Cytotoxicity studies revealed low cytotoxicity against three human cancer cell lines. Furthermore, molecular modeling approach was applied to probe the binding-conformation of the complex with ct-DNA/tRNA and the results showed that complex 1 exhibited preferential binding propensity towards ct-DNA.

我们在此描述了含有氨基喹啉配体的半夹心 Ru (II)( ƞ ⁶ - p -伞花烃) 复合物1的合成。配合物1 的特点是各种光谱和单晶 X 射线晶体学技术。“钢琴凳”复合物在三斜P 中结晶$\overline{1}$空间群与钌 (Ⅱ)( p -伞花烃) 片段拴在氨基喹啉的伯胺氮原子上。执行 DFT 计算以生成复合物1 的UV 和 IR 光谱，这进一步支持了实验数据。通过使用紫外-可见光、荧光、圆二色性和循环伏安技术对复合物进行了 DNA/RNA 结合的比较研究。复合物1与 ct-DNA 和 tRNA的内在结合常数计算为 3.9 × 10 ⁵ (±0.09) M ^-1和 2.45 × 10 ⁴ (±0.10) M ^-1这表明复合物的结合亲和力更强1对 ct-DNA。通过进行凝胶电泳研究了复合物对 pBR322 质粒的剪切效率。结果表明，复合物在 35 μM 浓度下诱导双链 DNA 切割，这是通过氧化途径介导的。还以浓度和时间依赖性方式进行了 RNA 凝胶断裂测定，在 24 小时孵育后观察到条带强度明显降低，这表明 tRNA 已完全裂解。还进行了复合物的 BSA 和溶菌酶结合研究，结果表明复合物1淬灭蛋白质的荧光强度。细胞毒性研究显示对三种人类癌细胞系的细胞毒性较低。此外，分子建模方法被应用于探测复合物与 ct-DNA/tRNA 的结合构象，结果表明复合物1表现出对 ct-DNA 的优先结合倾向。