一种细胞毒性双(1,2,3-三唑-5-亚基)咔唑并[1,2-a]苯并咪唑金(III)配合物通过部分嵌入靶向 DNA。
A Cytotoxic Bis(1,2,3-triazol-5-ylidene)carbazolide Gold(III) Complex Targets DNA by Partial Intercalation.
机构信息
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, 2050, Johannesburg, South Africa.
Department of Physiology, University of Pretoria, 0031, Pretoria, South Africa.
出版信息
Chemistry. 2021 Jun 4;27(32):8295-8307. doi: 10.1002/chem.202100598. Epub 2021 May 17.
The syntheses of bis(triazolium)carbazole precursors and their corresponding coinage metal (Au, Ag) complexes are reported. For alkylated triazolium salts, di- or tetranuclear complexes with bridging ligands were isolated, while the bis(aryl) analogue afforded a bis(carbene) Au -CNC pincer complex suitable for oxidation to the redox-stable [Au (CNC)Cl] cation. Although the ligand salt and the [Au (CNC)Cl] complex were both notably cytotoxic toward the breast cancer cell line MDA-MB-231, the Au complex was somewhat more selective. Electrophoresis, viscometry, UV-vis, CD and LD spectroscopy suggest the cytotoxic [Au (CNC)Cl] complex behaves as a partial DNA intercalator. In silico screening indicated that the [Au (CNC)Cl] complex can target DNA three-way junctions with good specificity, several other regular B-DNA forms, and Z-DNA. Multiple hydrophobic π-type interactions involving T and A bases appear to be important for B-form DNA binding, while phosphate O⋅⋅⋅Au interactions evidently underpin Z-DNA binding. The CNC ligand effectively stabilizes the Au ion, preventing reduction in the presence of glutathione. Both the redox stability and DNA affinity of the hit compound might be key factors underpinning its cytotoxicity in vitro.
报道了双(三唑𬭩)咔唑前体及其相应的金属(金、银)配合物的合成。对于烷基化的三唑𬭩盐,分离出具有桥连配体的二核或四核配合物,而双(芳基)类似物则提供了适合氧化为氧化还原稳定的[Au(CNC)Cl]阳离子的双(碳烯)Au-CNC 钳形配合物。尽管配体盐和[Au(CNC)Cl]配合物对乳腺癌细胞系 MDA-MB-231 均具有显著的细胞毒性,但 Au 配合物的选择性稍高。电泳、粘度、UV-vis、CD 和 LD 光谱表明,细胞毒性[Au(CNC)Cl]配合物作为部分 DNA 嵌入剂起作用。计算机筛选表明,[Au(CNC)Cl]配合物可以特异性地靶向 DNA 三链结,还可以靶向几种其他常规 B-DNA 形式和 Z-DNA。涉及 T 和 A 碱基的多个疏水性π型相互作用似乎对 B 型 DNA 结合很重要,而磷酸 O⋅⋅⋅Au 相互作用显然是 Z-DNA 结合的基础。CNC 配体有效地稳定了 Au 离子,在谷胱甘肽存在下阻止了还原。该候选化合物的氧化还原稳定性和 DNA 亲和力可能是其在体外具有细胞毒性的关键因素。