Making organoruthenium complexes of 8-hydroxyquinolines more hydrophilic: impact of a novel l-phenylalanine-derived arene ligand on the biological activity

Dalton Trans. 2018 Feb 13;47(7):2192-2201. doi: 10.1039/c7dt04451h.

Abstract

Ru(arene) compounds have many desirable features making them promising candidates for further development in anticancer drug research. While a lot of emphasis has been placed on the modification of the ancillary ligands, there are not many examples of arene ligands bearing functional groups. Herein, we report the preparation of [Ru(arene)(8-oxyquinolinato)Cl] complexes with the arene being a protected form of the amino acid l-phenylalanine and 8-oxyquinolinato ligand substituted with halogens. With this approach we aimed to alter the pharmacological properties of the complexes and address issues with the aqueous solubility of the analogous p-cymene complexes. The complexes were shown to be stable in DMSO and water and reacted readily with l-histidine and 9-ethylguanine as protein and DNA models, respectively. Assaying the antiproliferative activity in cancer cells gave IC50 values in the low μM range. While the lipophilicity of the p-cymene analogues correlated well with their in vitro cytotoxicity, the potency of the complexes with the l-phenylalanine-derived arene was independent of lipophilicity.

MeSH terms

  • Antineoplastic Agents / chemistry*
  • Antineoplastic Agents / pharmacology*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Drug Stability
  • Humans
  • Hydrophobic and Hydrophilic Interactions*
  • Ligands
  • Models, Molecular
  • Molecular Conformation
  • Oxyquinoline / chemistry*
  • Phenylalanine / chemistry*
  • Ruthenium / chemistry*

Substances

  • Antineoplastic Agents
  • Ligands
  • Phenylalanine
  • Oxyquinoline
  • Ruthenium