Heteroleptic Copper(I) Complexes of "Scorpionate" Bis-pyrazolyl Carboxylate Ligand with Auxiliary Phosphine as Potential Anticancer Agents: An Insight into Cytotoxic Mode

Sci Rep. 2017 Mar 24:7:45229. doi: 10.1038/srep45229.

Abstract

New copper(I) complexes [CuCl(PPh3)(L)] (1: L = LA = 4-carboxyphenyl)bis(3,5-dimethylpyrazolyl)methane; (2: L = LB = 3-carboxyphenyl)bis(3,5-dimethylpyrazolyl)methane) were prepared and characterised by elemental analysis and various spectroscopic techniques such as FT-IR, NMR, UV-Vis, and ESI-MS. The molecular structures of complexes 1 and 2 were analyzed by theoretical B3LYP/DFT method. Furthermore, in vitro DNA binding studies were carried out to check the ability of complexes 1 and 2 to interact with native calf thymus DNA (CT-DNA) using absorption titration, fluorescence quenching and circular dichroism, which is indicative of more avid binding of the complex 1. Moreover, DNA mobility assay was also conducted to study the concentration-dependent cleavage pattern of pBR322 DNA by complex 1, and the role of ROS species to have a mechanistic insight on the cleavage pattern, which ascertained substantial roles by both hydrolytic and oxidative pathways. Additionally, we analyzed the potential of the interaction of complex 1 with DNA and enzyme (Topo I and II) with the aid of molecular modeling. Furthermore, cytotoxic activity of complex 1 was tested against HepG2 cancer cell lines. Thus, the potential of the complex 1 is promising though further in vivo investigations may be required before subjecting it to clinical trials.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / chemical synthesis*
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / toxicity
  • Copper / chemistry*
  • DNA / chemistry*
  • DNA / metabolism
  • DNA Topoisomerases, Type I / chemistry
  • DNA Topoisomerases, Type I / metabolism
  • Hep G2 Cells
  • Humans
  • Molecular Docking Simulation*
  • Organometallic Compounds / chemical synthesis*
  • Organometallic Compounds / pharmacology
  • Organometallic Compounds / toxicity
  • Phosphines / chemistry
  • Pyrazoles / chemistry

Substances

  • Antineoplastic Agents
  • Organometallic Compounds
  • Phosphines
  • Pyrazoles
  • Copper
  • DNA
  • DNA Topoisomerases, Type I