Synthesis, crystal structure, and DNA cleavage activity of a dinuclear nickel(II) complex with a macrocyclic ligand

Abstract

A new Ni(II) complex, namely [Ni 2 (OAc)L]Á ClO 4 ÁH 2 O, was synthesized by [2 ? 2] cyclo-condensation between 2,6-diformyl-4-methylphenol and N,N-bis(3-aminopropyl)-4-methoxybenzylamine (amba) in the presence of nickel(II) and characterized by spectroscopy, elemental analysis, and X-ray single crystal diffraction. The interactions of the complex with DNA have been measured by spectroscopy and viscosity measurements. Absorption spectroscopic investigation reveals intercalative binding of the Ni(II) complex with DNA, with a binding constant of 2.6 9 10 4 M -1 . Fluorescence spectroscopy shows that the Ni(II) complex can displace ethidium bromide and bind to DNA, with a quenching constant of 7.57 9 10 3 M -1 . The appearance of increased CD bands near 245 and 275 nm gives evidence for effective complex DNA binding. The agarose gel electrophoresis studies show that the complex displays effective DNA cleavage activity in the absence of any external agents.

Template‐Directed Synthesis of Two Dinuclear Ni(II) Complexes together with Their Interconversion, Crystal Structures and DNA‐Binding Studies

“…The values of K b for complexes are consistent with the interaction between the reported macrocyclic molecules and DNA (10 4 ∼ 10 5 M À 1 ). [16,30] In the paper, the binding activity of B is stronger than A, which indicated that the metal coordinate environment and the distance between center Ni(II) atoms play an important role in DNA cleavage. [35][36]…”

“…The distance between Ni1 and Ni2 is 2.9413(7) Å, samller than the similar dinuclear Ni(II) macrocyclic complexes. [16][17][18] The dihedral angle between the (N amine ) 2 O 2 and (N imine ) 2 O 2 plane is 23.68(73)°. Hydrogen-bond interactions play an important role in maintaining the 3-D network.…”

[2-Formyl-4-methyl-6-({2-[2-(4-nitrobenzylamino)ethylamino]ethylimino}methyl)phenolato]nickel(II) perchlorate

“…2,6-Diformyl-4-methylphenol was prepared according to the literature method (Mandal et al 1989;Long et al 1983). N 1 -(2-aminoethyl)-N 2 -(4nitrobenzyl)ethane-1,2-diamine was prepared according to the literature method (Jian et al 2004;Hu et al 2011). L 2 (0.119 g, 0.5 mmol) dissolved in 10 mL water was added dropwise to a solution of L 1 (0.082 g, 0.5 mmol) and…”

“…For the synthesis, see: Zhou et al (2009). For the preparation of 2,6diformyl-4-methylphenol, see: Long & Hendrickson (1983); Mandal et al (1989) and for the preparation of N 1 -(2-aminoethyl)-N 2 -(4-nitrobenzyl)ethane-1,2-diamine, see: Hu et al (2011);Jian et al (2004).…”

A New Isoindoline Based Schiff Base Derivative as Cu(II) Chemosensor: Synthesis, Photophysical, DNA Binding and Molecular Docking Studies

“…In order to get insight into the DNA binding strength of this compound, the intrinsic binding constant K b was calculated using the following equation [36].…”