Synthesis and electronic structure of novel Schiff bases Ni/Cu (II) complexes: Evaluation of DNA/serum protein binding by spectroscopic studies
作者:Maryam Sedighipoor、Ali Hossein Kianfar、Wan Ahmad Kamil Mahmood、Mohammad Hossein Azarian
DOI:10.1016/j.poly.2017.03.027
日期:2017.6
[Cu(L)] (1) and [Ni(L)] (2) [L = N-2-hydroxyacetophenon-N'-2-hydroxynaphthaldehyde-1,2 phenylenediimine)], Schiff base complexes have been successfully synthesized. Single crystal X-ray crystallography, Fourier Transform infrared spectroscopy (FT-IR), NMR spectroscopy and elemental analysis (EA) have been used to characterize the complexes. Complex 1 shows unsymmetrical ligand coordination to copper (II) ion in a tetradentate fashion through ONNO donor atoms according to single crystal X-ray patterns. Spectroscopic methods have been used to study the interactions between the synthesized Schiff base complexes and Calf Thymus DNA (CT-DNA) and Bovine Serum Albumin (BSA) under physiological conditions. UV-vis absorption, fluorescence, and circular dichroism (CD) spectroscopy and thermal denaturation measurements were used in the investigation of DNA binding properties of these two complexes. The two complexes can bind to Calf Thymus DNA (CT-DNA) via an intercalative mode and complex 1 exhibits stronger interaction with CT-DNA compared with complex 2 based on the results. In addition, both compounds interact with BSA to change its microenvironment during interaction. Cu (II) complex has more affinity for BSA based on the quenching (K-sv) and binding constant (K-b) values of both compounds with BSA. Circular Dichroism technique has been applied to investigate the conformational changes of the interactions of metal complexes with DNA. Also thermal behavior of DNA-complex interaction has been determined. (C) 2017 Elsevier Ltd. All rights reserved.