New anthracene based Schiff base ligands appended Cu(II) complexes: Theoretical study, DNA binding and cleavage activities. (16th October 2017)

• Record Type: Journal Article
• Authors: Gubendran, Ammavasai; Kumar, Gujuluva Gangatharan Vinoth; Kesavan, Mookkandi Palsamy; Rajagopal, Gurusamy; Athappan, Periakaruppan; Rajesh, Jegathalaprathaban
• Is Part Of: Applied organometallic chemistry. Volume 32:Number 3(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-10-16
• Subjects: characterization -- Cu(II) complexes -- DNA binding -- DNA cleavage -- Schiff base ligands -- theoretical studies; Organometallic chemistry -- Periodicals; Organometallic compounds -- Periodicals; 547.05
• DOI: 10.1002/aoc.4128
• Languages: English
• ISSNs: 0268-2605

Abstract

Abstract : New anthracene based Schiff base ligandsL 1 and H(L 2 ), their Cu(II) complexes [Cu(L 1 )Cl2 ] (1 ) and [Cu(L 2 )Cl] (2 ), (whereL 1 = N 1, N 2 ‐ bis (anthracene‐9‐methylene)benzene‐1, 2‐diamine, L 2 = (2 Z, 4 E )‐4‐(2‐(anthracen‐9‐ylmethyleneamino)phenylimino)pent‐2‐en‐2‐ol) have been prepared and characterized by elemental analysis, NMR, FAB‐mass, EPR, FT‐IR, UV–Vis and cyclic voltammetry. The electronic structures and geometrical parameters of complexes1 and2 were analyzed by the theoretical B3LYP/DFT method. The interaction of these complexes1 and2 with CT‐DNA has been explored by using absorption, cyclic voltammetric and CD spectral studies. From the electronic absorption spectral studies, it was found that the DNA binding constants of complexes1 and2 are 8.7 × 10 3 and 7.0 × 10 4 M −1, respectively. From electrochemical studies, the ratio of DNA binding constants K+ /K2+ for2 has been estimated to be >1. The high binding constant values, K+ /K2+ ratios more than unity and positive shift of voltammetric E1/2 value on titration with DNA for complex2 suggest that they bind more avidly with DNA than complex1 . The inability to affect the conformational changes of DNA in the CD spectrum is the definite evidences of electrostatic binding by the complex1 . It can be assumed that it is the bulky anthracene unit which sterically inhibits these complexes1 and2 from intercalation and thereby remains in the groove or electrostatic. The complex2 hardly cleaves supercoiled pUC18 plasmid DNA in the presence of hydrogen peroxide. The results suggest that complex2 bind to DNA through minor groove binding. Abstract : New Cu(II) complexes1 and2 of anthracene based Schiff base ligands. Characterization using various spectral and analytical tools. Geometrical parameters of Cu(II) complexes were analyzed by theoretical method. Complex2 has effective DNA binding behavior than complex1 . Complex2 comprises substantial DNA cleavage activity.