Synthesis, crystal structure, magnetic property and nuclease activity of a new binuclear cobat(II) complex

One new binuclear Co(II) complex of N,N,N′,N′-tetrakis(2-benzimidazolylmethyl)-2-hydroxyl-1,3-diaminopropane (HL), [Co2L(μ2- Cl)](ClO4)2 · 3CH3CN · C2H5OC2H5 (1), has been synthesized and its crystal structure and magnetic properties are shown. In 1, each Co(II) atom has a distorted trigonal bipyramidal geometry with a N3OCl donor set. The central two Co(II) atoms are bridged by one alkoxo-O atom and one Cl atom with the Co1–Co2 separation of 3.239 Å. Susceptibility data of 1 indicate strong intramolecular antiferromagnetic coupling of the high-spin Co(II) atoms. In this paper, the interaction with calf thymus DNA was investigated by UV absorption and fluorescent spectroscopy. Results show the complex binds to ct-DNA with a intercalative mode. The interaction between complex 1 and pBR322 DNA has also been investigated by submarine gel electrophoresis, noticeably, the complex exhibits effective DNA cleavage activity in the absence of any external agents.