2‐Hydroxynaphthalene‐1‐carbaldehyde‐ and 2‐(Aminomethyl)pyridine‐Based Schiff Base Cu^II Complexes for DNA Binding and Cleavage

Abstract

Three mononuclear Cu(II) complexes, [CuCl(naph-pa)] (1), [Cu(bipy)(naph-pa)]Cl (2), and [Cu(naph-pa)(phen)]Cl (3) ((naph-pa)=Schiff base derived from the condensation of 2-hydroxynaphthalene-1-carbaldehyde and 2-picolylamine (=2-(aminomethyl)pyridine), bipy=2,2'-bypiridine, and phen=1,10-phenanthroline) were synthesized and characterized. Complex 1 exhibits square-planar geometry, and 2 and 3 exhibit square pyramidal geometry, where Schiff base and bipy/phen act as NNO and as NN donor ligands, respectively. CT (Calf thymus)-DNA-binding studies revealed that the complexes bind through intercalative mode and show good binding propensity (intrinsic binding constant K(b): 0.98×10(5), 2.22×10(5), and 2.67×10(5) M(-1) for 1-3, resp.). The oxidative and hydrolytic DNA-cleavage activity of these complexes has been studied by gel electrophoresis: all the complexes displayed chemical nuclease activity in the presence and absence of H(2)O(2). From the kinetic experiments, hydrolytic DNA cleavage rate constants were determined as 2.48, 3.32, and 4.10 h(-1) for 1-3, respectively. It amounts to (0.68-1.14)×10(8)-fold rate enhancement compared to non-catalyzed DNA cleavage, which is impressive. The complexes display binding and cleavage propensity to DNA in the order of 3>2>1.

Synthesis and Characterisation of Copper(II) Complexes with Tridentate NNO Functionalized Ligand: Density Function Theory Study, DNA Binding Mechanism, Optical Properties, and Biological Application

“…For example, pyridine derivatives, such as (aromatic) alkoxyl pyridine compounds, amidopyridine, and its derivatives, substituted fused pyridine compounds, have already been widely applied in the fields of agrochemical products [ 11 ]. Moreover, pyridine derivatives play a unique role in anthelminthic, acaricide, bacteriocide, and phytocide [ 12 ]. For these biological effects we choose the pyridine derivative ligand as a starting material.…”

Anticancer Function and ROS-Mediated Multi-Targeting Anticancer Mechanisms of Copper (II) 2-hydroxy-1-naphthaldehyde Complexes

“…The ligand was synthesized according to the previously reported protocol [70]. 2-hydroxy-1-naphthaldehyde and (2-(aminomethyl) pyridine) (0.5 mmol) were dissolved in a 20 mL aqueous methanol solution and stirred for 3 h at 65 °C, yielding a dark brown solution, yield: 79.6%.…”

A Schiff Base and Its Copper(II) Complex as a Highly Selective Chemodosimeter for Mercury(II) Involving Preferential Hydrolysis of Aldimine over an Ester Group

“…The electronic absorption spectrum of HL [ c , 50 μM; 9:1 (v/v) MeOH/H 2 O; pH ∼7.2] exhibited two prominent bands at 338 nm (ε, 1.24 × 10 4 M –1 cm –1 ) and 274 nm (ε, 1.77 × 10 4 M –1 cm –1 ). The low-energy (LE) band at 338 nm has been tentatively assigned to n−π* transitionsand the high-energy (HE) band at 274 nm to the π–π* transitions . To examine the interaction of HL with various cations, a solution of this compound was treated with 10.0 equiv of nitrate salts of Na + , K + , Mg 2+ , Ca 2+ , Mn 2+ , Co 2+ , Ni 2+ , Zn 2+ , Cd 2+ , Ag + , Pb 2+ , Cu 2+ , and Hg 2+ .…”

“…The low-energy (LE) band at 338 nm has been tentatively assigned to n−π* transitionsand the high-energy (HE) band at 274 nm to the π−π* transitions. 29 To examine the interaction of HL with various cations, a solution of this compound was treated with 10.0 equiv of nitrate salts of Na + , K + , Mg 2+ , Ca 2+ , Mn 2+ , Co 2+ , Ni 2+ , Zn 2+ , Cd 2+ , Ag + , Pb 2+ , Cu 2+ , and Hg 2+ . This exhibited insignificant changes in the presence of the aforesaid metal ions except for Cu 2+ and Hg 2+ (Figure 3a).…”