Synthesis, structure characterization, DNA binding, and cleavage properties of mononuclear and tetranuclear cluster of copper(II) complexes

Abstract

Two copper(II) complexes, cluster 1, and mononuclear 2, have been synthesized by reacting acetylacetone and benzohydrazide (1:1 ratio for 1 and 1:2 ratio for 2) with CuCl 2 in a methanol solution. In 2, which is a new complex, the ligand acts as a tetradentate which binds the metal ion via two amide-O atoms and two imine-N atoms providing an N 2 O 2 square-planar around the copper(II) ion. The absorption spectra data evidence strongly suggested that the two copper(II) compounds could interact with CT-DNA (intrinsic binding constant, K b = 0.45 × 10 4 M-1 for 1 and K b = 2.39 × 10 4 M-1 for 2). The super coiled plasmid pBR322 DNA cleavage ability was studied with 1 and 2 in the presence and absence of H 2 O 2 as an oxidant. In both the absence and the presence of an oxidizing agent, complex 2 exhibited no nuclease activity. However, even in the absence of an oxidant, complex 1 exhibited significant DNA cleavage activity.

Synthesis, Characterization and DFT-Based Investigation of a Novel Trinuclear Singly-Chloro-Bridged Copper(II)-1-Vinylimidazole Complex

“…The most abundant signal at m/z = 991. 5 [Na+complex] in TOF-MS spectrum of the complex in Figure 4 is related to sodiated adduct of the trinuclear structure since the spectrum was taken in positive ion mode. Designation of other significant peaks is not possible due to probably different stable adducts and fragments in solution medium.…”

“…Among these, polynuclear copper(II) species [4][5][6][7][8] are the most intriguing and investigated ones due to their plain structural properties, ability to mimic active sites in certain copper containing proteins and easy to rationalize and diverse magnetic properties as the simplest examples of magnetic exchange interactions. [9][10][11][12][13][14] From another standpoint, the selection or design of the organic ligands are of cruical importance on self-assembly of metal ions owing to their requisite functional roles as transmitters of close metalmetal communications other than they are the backbones of these polynuclear aggregates.…”

New Bioactive Heteroleptic Copper(II) Carboxylates: Structure, Enzymatic and DNA-Binding Studies

“…Metal charge, interactions with ligands, structure and bonding, Lewis acid character, partially filled d-shell and its redox activity defines its suitability for biological systems. [7][8][9][10] Copper is one of essential metals with multifaceted role in human life. It has been used as medicine for healing purposes since ancient civilizations.…”

Synthesis of Hetero- and Homo-multinuclear Complexes with a Tetracyanonickelate Anion: Structural Characterization [Cu(bcen)Ni(CN)4]2

“…[6][7][8][9][10] Self-assembly is the most efficient approach for the construction of such molecular systems. [11][12][13] Another popular and successful approach for the preparation of multinuclear complexes with unusual and interesting properties is to employ cyano complexes (metalloligand) such as Ag(CN) 2 -, Ni(CN) 4 2-, Cr(CN) 6 3-, Pd(CN) 4 2-, Pt(CN) 4 2-, etc. [14][15][16][17] The cyano anion is able to act either as a terminal or as a bridging ligand.…”