Three new organotin(IV) carboxylate compounds were synthesized and structurally characterized by elemental analysis and FT-IR and multinuclear NMR (¹H, ¹³C, ¹¹⁹Sn) spectroscopy. Single X-ray crystallography reveals that compound C2 has a monoclinic crystal system with space group P2₁/c having distorted bipyramidal geometry defined by C₃SnO₂. The synthesized compounds were screened for drug-DNA interactions via UV-Vis spectroscopy and cyclic voltammetry showing good activity with high binding constants. Theoretical investigations also support the reactivity of the compounds as depicted from natural bond orbital (NBO) analysis using Gaussian 09. Synthesized compounds were initially evaluated on two cancer (HeLa and MCF-7) cell lines and cytotoxicity to normal cells was evaluated using a non-cancerous (BHK-21) cell line. All the compounds were found to be active, with IC₅₀ values less than that of the standard drug i.e. cisplatin. The cytotoxic effect of the most potent compound C2 was confirmed by LDH cytotoxicity assay and fluorescence imaging after PI staining. Apoptotic features in compound C2 treated cancer cells were visualized after DAPI staining while regulation of apoptosis was observed by reactive oxygen species generation, binding of C2 with DNA, a change in mitochondrial membrane potential and expression of activated caspase-9 and caspase-3 in cancer cells. Results are indicative of activation of the intrinsic pathway of apoptosis in C2 treated cancer cells.

中文翻译：

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具有芳香族羧酸酯配体的新型三有机锡(IV)化合物：促凋亡机制的合成和评估

合成了三种新的有机锡( IV )羧酸盐化合物，并通过元素分析、FT-IR 和多核NMR ( ¹ H, ¹³ C, ¹¹⁹ Sn) 光谱进行了结构表征。单X射线晶体学表明，化合物C2具有单斜晶系，其空间群P 2 ₁ / c具有由C ₃ SnO ₂定义的扭曲双锥体几何形状。通过紫外-可见光谱和循环伏安法筛选合成的化合物的药物-DNA 相互作用，显示出良好的活性和高结合常数。理论研究还支持使用 Gaussian 09 的自然键轨道 (NBO) 分析所描绘的化合物的反应性。合成的化合物最初在两种癌症（HeLa 和 MCF-7）细胞系上进行了评估，并使用非-癌（BHK-21）细胞系。发现所有化合物均具有活性，其IC ₅₀值低于标准药物（即顺铂）的IC 50 值。最有效的化合物C2的细胞毒性作用通过 LDH 细胞毒性测定和 PI 染色后的荧光成像得到证实。DAPI 染色后，化合物C2处理的癌细胞的凋亡特征可见，同时通过活性氧的产生、C2与 DNA 的结合、线粒体膜电位的变化以及癌症中活化的 caspase-9 和 caspase-3 的表达来观察细胞凋亡的调节细胞。结果表明C2处理的癌细胞中细胞凋亡的内在途径被激活。