Synthesis, structure and comparison of the DNA cleavage ability of metal complexes M(<scp>ii</scp>)L with the N-(2-ethoxyethanol)-bis(2-picolyl)amine ligand L (M = Co, Ni, Cu and Zn)
作者:Srecko I. Kirin、Christoph M. Happel、Silvia Hrubanova、Thomas Weyhermüller、Christoph Klein、Nils Metzler-Nolte
DOI:10.1039/b313634e
日期:——
Complexes of a N,N-bis(2-picolyl)amine (bpa) derivative with a pendant ethoxyethanol side chain (bpa(CH2)2O(CH2)2OH)
(1) with late divalent transition metal ions Co(II), Ni(II), Cu(II) and Zn(II) have been studied. All complexes, [bpa(CH2)2O(CH2)2OH}Co(NO3)](NO3)
(1Co), [bpa(CH2)2O(CH2)2OH}Ni(NO3)](NO3)
(1Ni), [bpa(CH2)2O(CH2)2OH}Cu(H2O)(NO3)](NO3)
(1Cu) and [bpa(CH2)2O(CH2)2OH}Zn(NO3)](NO3)
(1Zn), were comprehensively characterized and their X-ray single crystal structures have been determined. The complexes show hexacoordinated geometries, in which 1 acts as a tetradentate (1Cu) or pentadentate (1Co, 1Ni and 1Zn) ligand. DNA cleavage experiments have been performed on supercoiled double stranded DNA plasmids in order to compare the cleavage efficiency of all four metals in the same ligand environment of 1. In this assay, 1Co and 1Cu showed the highest cleavage efficiency, whereas 1Ni and 1Zn were virtually inactive. Quantification of the gel electrophoresis bands showed that more than 80% of the plasmid has suffered at least one single strand cut in the case of 1Cu, and about 50% of the plasmid was nicked by 1Co. The differential cleavage activity is discussed in relation to the structural findings and a mechanism is proposed for 1Cu.
研究了带有乙氧基乙醇侧链的 N,N-双(2-吡啶基)胺(bpa)衍生物(bpa(CH2)2O(CH2)2OH)(1) 与晚期二价过渡金属离子 Co(II)、Ni(II)、Cu(II) 和 Zn(II) 的络合物。所有配合物,[bpa(CH2)2O(CH2)2OH}Co(NO3)](NO3) (1Co), [bpa(CH2)2O(CH2)2OH}Ni(NO3)](NO3) (1Ni)、(NO3)(1Ni)、[bpa(CH2)2O(CH2)2OH}Cu(H2O)(NO3)](NO3)(1Cu)和[bpa(CH2)2O(CH2)2OH}Zn(NO3)](NO3)(1Zn)进行了全面表征并确定了它们的 X 射线单晶结构。这些配合物呈现出六配位几何结构,其中 1 充当了四配位(1Cu)或五配位(1Co、1Ni 和 1Zn)配体。为了比较所有四种金属在 1 的相同配体环境中的裂解效率,我们在超卷曲双链 DNA 质粒上进行了 DNA 裂解实验。在该实验中,1Co 和 1Cu 的裂解效率最高,而 1Ni 和 1Zn 几乎没有作用。凝胶电泳条带的定量显示,在 1Cu 的情况下,超过 80% 的质粒受到至少一条单链的切割,而 1Co 则切割了约 50% 的质粒。本文结合结构研究结果对不同的切割活性进行了讨论,并提出了 1Cu 的作用机制。