Design and investigation of photoactivatable platinum(iv) prodrug complexes of cisplatin

Dalton Trans. 2019 Jun 7;48(21):7388-7393. doi: 10.1039/c9dt00540d. Epub 2019 Apr 8.

Abstract

Platinum(iv) carboxylate scaffolds have garnered considerable research interest because they can be engineered to function as prodrugs of clinical platinum(ii) anticancer drugs. These platinum(iv) prodrug complexes are stable and tunable, and activated by reduction to release their cytotoxic platinum(ii) cargo. Here we propose new platinum(iv) prodrug complexes designed to release cisplatin via photoreduction upon UV irradiation. The central strategy is to utilise aryl carboxylate ligands on the axial positions of that platinum(iv) scaffold that confer significant UV absorption and would stabilise carboxyl radical formation, thus favouring homolytic Pt-O bond cleavage. We isolated and identified aryl carboxyl radicals via spin-trapping and showed that the photoreduced platinum species mirror cisplatin reactivity toward DNA bases, thereby validating the efficacy of this approach.

MeSH terms

  • Antineoplastic Agents / chemical synthesis*
  • Cisplatin / chemistry
  • Coordination Complexes / chemical synthesis*
  • Ligands
  • Organoplatinum Compounds / chemical synthesis*
  • Oxidation-Reduction
  • Prodrugs / chemical synthesis*
  • Structure-Activity Relationship
  • Ultraviolet Rays

Substances

  • Antineoplastic Agents
  • Coordination Complexes
  • Ligands
  • Organoplatinum Compounds
  • Prodrugs
  • Cisplatin