Two polypyridyl copper(ii) complexes: synthesis, crystal structure and interaction with DNA and serum protein in vitro

Abstract

Two polypyridyl copper(II) complexes, [Cu(acac)(p-CPIP)(CH 3 OH)](NO 3 ) (1) and [Cu(acac)1,10-phenanthroline), have been synthesized and characterized by singlecrystal analysis, IR and electronic spectroscopy. X-ray analyses reveal that both 1 and 2 possess a triclinic crystal system with Pmn1 and mononuclear five-coordinated square pyramidal geometry, which were further linked to a one-dimensional structure through p-p stacking and intermolecular hydrogen bonds.The interaction of the Cu(II) complex with calf thymus DNA (CT-DNA) was investigated by UV-visible and fluorescence emission spectrometry, as well as agarose gel electrophoresis. The apparent binding constant (K app ) values of 2.47 Â 10 4 M À1 for 1 and 3.04 Â 10 4 M À1 for 2 suggest moderate intercalative binding mode between the complexes and DNA. Both complexes displayed efficient oxidative cleavage of supercoiled DNA in the presence of external agents. In addition, fluorescence spectrometry of bovine serum albumin (BSA) with the complexes showed that the quenching mechanism of 1 might be a dynamic procedure, while 2 showed a combined dynamic and static quenching mechanism. For both 1 and 2, the number of binding sites was about one for BSA. Moreover, synchronous fluorescence spectral experiments revealed that 1 and 2 affect the microenvironment of tryptophan residues of BSA.

Nuclear blebbing of biologically active organoselenium compound towards human cervical cancer cell (HeLa): In vitro DNA/HSA binding, cleavage and cell imaging studies

“…The observed decrease in the fluorescence intensity with a strong red shift clearly indicates that the EB molecule was displaced by the 1 from their DNA binding sites [25]. Furthermore; the quenching extents was evaluated quantitatively by employing Stern-Volmer equation.…”

Effect of hydrophobicity on intercalative binding of some surfactant copper(II) complexes with tRNA

“…Because the surfactant complex 3 containing the ligand benzo [1]dipyrido[3,2-a 0 :2 0 ,3 0 -c] phenazine (dppn) possesses the largest planar area and extended p system which can penetrate more deeply and stack more strongly into tRNA compared to other systems.…”

“…Among the transition metal complexes studied in this context, copper(II) complexes with polypyridyl ligands have attracted considerable attention [1][2][3]. Binding studies of small molecules to DNA are very important in the growth of DNA structure probes, molecular light switches, chemotherapy, and photodynamic therapy etc.…”

“…In this work, the tRNA-binding study of three copper(II) surfactant metal complexes with nitrogen donor polypyridyl derivative as primary ligand (imidazo [4,5-f] [1,10] phenanthroline (ip), 6,7,8,9-tetrahydrodipyrido[3,2-a:2 0 ,4 0 -c] phenazine (dpqc), and benzo [1]dipyrido[3,2-a 0 :2 0 ,3 0 -c] phenazine (dppn)) and dodecylamine as co-ligand has been presented. UV-Vis absorption, competitive binding, cyclic voltammetry, and viscosity measurements were used for these studies.…”

A new thio-Schiff base fluorophore with copper ion sensing, DNA binding and nuclease activity

“…However, despite being a prominent class of molecules in the field of bioorganic chemistry, studies concerning DNA interaction of Schiff base are still rare. DNA binding studies are of vital importance in the process of designing chemotherapeutic agents because information from these studies is required to improve aspects such as toxicity, efficacy and target specificity of a drug [20][21][22]. Hence in this paper, we report the copper ion recognition and DNA binding properties of a new fluorescent thio-Schiff base (HPyETSC) studied by UV-vis spectroscopy and fluorescent spectroscopy.…”