High Cytotoxicity of Ruthenium(II) and Gold(I) Bimetallic Complexes and Its Precursors

Area of Science:

• Inorganic Chemistry
• Medicinal Chemistry
• Materials Science

Background:

• Ruthenium(II) and gold(I) complexes are explored for anticancer properties.
• Bimetallic compounds offer unique structural and electronic characteristics.
• Pincer ligands can modulate biological activity.

Purpose of the Study:

• Synthesize and characterize novel Ru(II)-PC(n)P-Au(I) bimetallic complexes.
• Investigate structure-activity relationships.
• Evaluate anticancer potential against human cancer cell lines.

Main Methods:

• Synthesis and full characterization of bimetallic complexes.
• Nuclear Magnetic Resonance (NMR) spectroscopy (31P{H}, 1H).
• Electrospray Ionization Mass Spectrometry (ESI-MS).
• Single-crystal X-ray diffraction.
• Hirshfeld surface analysis.
• In vitro cytotoxicity assays against HeLa and Caco2 cells.

Main Results:

• Successful synthesis and structural confirmation of Ru(II)-PC(n)P-Au(I) complexes (n=1-5).
• NMR and crystallographic data provided insights into electronic environments and molecular structures.
• Hirshfeld analysis revealed systematic variations in intermolecular interactions based on ligand chain length.
• Complexes demonstrated superior cytotoxicity compared to cisplatin and melphalan.
• Activity showed cell-specific dependence on pincer ligand carbon chain length.
• Compound 2b exhibited potent cytostatic activity and selectivity.

Conclusions:

• Established structure-property relationships for the bimetallic complexes.
• Demonstrated significant anticancer potential, particularly compound 2b.
• Highlighted the influence of ligand design on biological efficacy.
• The complexes represent promising candidates for novel anticancer drug development.