摘要
用多吡啶配体L(L=4′-苯基-2,2′:6′,2″-三吡啶)合成了两个镍配合物[Ni(L)_2](NO_3)_2(1)和[Ni (L)_2]Cl_2·10H_2O(2),其单晶结构均属于三斜晶系.中心镍离子与两个配体上的六个氮原子配位构成变形八面体结构.配合物2中由Cl_(2A)…O_(6A)…O_(5A)…Cl_(2B)…O_(6B)…O_(5B)构成的六员氢键环呈椅式构象.用电子光谱、荧光光谱研究了它们与小牛胸腺DNA之间的相互作用.随着DNA的加入,电子光谱的最大吸收峰明显红移(14 nm)并伴随有减色效应;同时配合物也能较大程度淬灭EB-DNA复合物的荧光,表观键合常数K_(app)分别为1.34×10~6和1.27×10~6mol^(-1)L.结果表明,两配合物均以较强的插入方式与DNA作用.
Two nickel (Ⅱ) complexes ENi(L)2](NO3)2(1) and ENi(L)2]Cl2.10H2O(2) (L=4′-phenyl-2, 2′ :6′, 2′-terpyridine) have been synthesized and structurally characterized. Both of the complexes crystallize in the triclinic system, space group. The central Ni ( Ⅱ ) ions are coordinated by six nitrogen atoms from the two single tridentate ligands L and possess distorted octahedral geometry. Especially, in complex 2 the hexacyclic hydrogen-bonded ring adopted a chair conformation is constructed via the hydrogen bonds of Cl2A…O6A…O5A… Cl2B…O6B…O5B. Moreover, UV-vis spectra and fluorescence spectra of complexes with calf thymus (CT)-DNA have also been determined. Upon addition of an increasing amount of CT-DNA to the complexes, a remarkable hypochromism and a visible red shift (14 nm) were observed in UV-vis spectrum. The apparent binding constant (Kapp) values for complex 1 and 2 are 1.34×10^6 and 1.27×10^6 mol^-1L for the fluorescence quenching emission spectra of EB-DNA, respectively. The results suggest that the interaction of two complexes with CT- DNA is a strong intercalative mode.
出处
《南开大学学报(自然科学版)》
CAS
CSCD
北大核心
2008年第6期19-25,38,共8页
Acta Scientiarum Naturalium Universitatis Nankaiensis
基金
Supported by the NNSF of China(20771063,20331020)