Anticancer potential of benzo[b]thiophene functionalized thiosemicarbazone ligands and their organoruthenium complexes


Öztürk E., SUBAŞI E., Kurşunluoğlu G., Yüksel B. Ş., AYAR KAYALI H.

Journal of Biological Inorganic Chemistry, 2025 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2025
  • Doi Number: 10.1007/s00775-024-02090-w
  • Journal Name: Journal of Biological Inorganic Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, BIOSIS, Chemical Abstracts Core, MEDLINE
  • Keywords: Organoruthenium-arene complexes, Thiosemicarbazone, Anticarcinogenic activity, Ovarian cancer cell lines, Crystal structure
  • Erciyes University Affiliated: No

Abstract

As novel promising anticancer candidates, the piano-stool type complexes of ruthenium, [RuCl(η6-p-cymene)(N,S-Ln)]PF6, K1-4, were synthesized from the reaction of the substituted benzo[b]thiophene based thiosemicarbazone ligands (L1-4) with [{RuCl(η6-p-cymene)}2(μ-Cl)2]. All complexes were fully characterized using elemental analysis, and spectroscopic methods such as FT-IR and 1H NMR. The molecular masses of the complexes were proved by MALDI-TOF analysis. Single crystal X-ray diffraction study was employed in the structural elucidation of complex K1 which shows a distorted octahedral geometry around the Ru(II) ion. Furthermore, spectroscopic methods revealed that in all complexes the ligands are coordinated to the metal center in neutral thione form via N, S donors. In this study, the effect of all ligands, complexes and commercial drugs with a different concentration on the viability of OVCAR-3, A2780 and OSE cells were compared. In this comparison, the cytotoxicity of ruthenium (II) complexes on two ovarian cancer cell lines (human A2780 and human OVCAR-3) was evaluated. For this purpose, the resazurin assay was performed. Based on our studies, complex K2 showed the highest toxicity against OVCAR-3 and A2780 cells. The cytotoxic effect of K2 was found to be higher than that of the commercial anticancer agents Oxalpin and Carbodex, 1.8–34.7-fold for OVCAR-3 cells and 1.9–11.8-fold for A2780 cells, respectively. These results provide insight into the potential of ruthenium (II) complexes as a cytotoxic agent for the treatment of ovarian cancer, particularly for primary tumors.