Jump to main content
Jump to site search

Issue 7, 2016
Previous Article Next Article

Effects of N,N-heterocyclic ligands on the in vitro cytotoxicity and DNA interactions of copper(II) chloride complexes from amidino-O-methylurea ligands

Author affiliations

Abstract

Copper(II) complexes based on guanidine derivatives have been synthesized by the addition of N,N-heterocyclic ligands, yielding four new compounds, [Cu(L1)(bipy)]Cl2 (1), [Cu(L1)(phen)]Cl2 (2), [Cu(L2)(bipy)Cl2] (3) and [Cu(L2)(phen)]Cl2 (4) (L1 = amidino-O-methylurea, L2 = N-(benzyl)-amidino-O-methylurea, bipy = 2,2′-bipyridine and phen = 1,10-phenanthroline), and their biological activities have been studied. All complexes were characterized by elemental analysis and various spectroscopic methods (FT-IR, mass, diffuse reflectance, UV-Vis and EPR). Their structures were proposed to be square planar (for 1, 2 and 4) and distorted octahedral (for 3). Their interactions with calf thymus (CT) DNA were examined by electronic absorption titration, viscosity measurements, circular dichroism spectroscopy, DNA-melting analysis, fluorescence spectroscopy and determination of the stoichiometry. Two possible DNA-binding modes of the complexes are proposed to be non-intercalation at low [complex]/[DNA] ratios and intercalation at high [complex]/[DNA] ratios. Their nuclease activities, investigated by gel-electrophoresis and atomic-force microscopy (AFM), show that the complexes can cleave plasmid pBR322 DNA, probably through oxidative pathways. Moreover, their in vitro cytotoxic activities against three human tumor cell lines (small cell lung carcinoma (NCI-H187), oral cavity carcinoma (KB) and breast adenocarcinoma (MCF-7)) and their antibacterial activities toward three Gram negative bacteria (E. coli, Salmonella and Campylobacter) were determined. The complexes in this system exhibit a more potent anticancer effect against the NCI-H187 cell line. Complex 2 had the best inhibition efficiency, particularly against Campylobacter. Indeed, the biological activities of the complexes follow the trend of 2 > 4 > 1 > 3.

Graphical abstract: Effects of N,N-heterocyclic ligands on the in vitro cytotoxicity and DNA interactions of copper(ii) chloride complexes from amidino-O-methylurea ligands

Back to tab navigation

Supplementary files

Publication details

The article was received on 04 Dec 2015, accepted on 19 Apr 2016 and first published on 05 May 2016


Article type: Paper
DOI: 10.1039/C5NJ03439F
Citation: New J. Chem., 2016,40, 5861-5876
  •   Request permissions

    Effects of N,N-heterocyclic ligands on the in vitro cytotoxicity and DNA interactions of copper(II) chloride complexes from amidino-O-methylurea ligands

    A. Meenongwa, R. F. Brissos, C. Soikum, P. Chaveerach, P. Gamez, Y. Trongpanich and U. Chaveerach, New J. Chem., 2016, 40, 5861
    DOI: 10.1039/C5NJ03439F

Search articles by author

Spotlight

Advertisements