Five new complexes with deferiprone and N,N-donor ligands: evaluation of cytotoxicity against breast cancer MCF-7 cell line and HSA-binding determination

Abstract

In this study, five new complexes containing deferiprone (dfp) and N,N-donor ligands [bipyridine (bpy), 1,10-phenanthroline (phen) and ethylenediamine (en)] were synthesized: [Fe(dfp)₂(bpy)](PF₆) (1), [Fe(dfp)₂(phen)](PF₆) (2), [Cu₂(dfp)₂(bpy)₂](PF₆)₂ (3), [Ga(dfp)₂(bpy)](PF₆) (4), and [Fe(dfp)₂(en)](PF₆) (5). Characterization of these complexes was carried out through elemental analysis and FT-IR, and single-crystal X-ray crystallography was used to determine their structures. Whilst the polyhedron has a distorted octahedral geometry in 1, 2, 4, and 5, it adopts a distorted square-pyramidal geometry in 3. Interaction of these compounds with human serum albumin (HSA) has been investigated through electronic absorption and fluorescence titration techniques. Emission quenching was performed separately for each complex at three different temperatures and thermodynamic parameters were calculated using binding constants to better understand the power of different binding forces with the HSA. Results demonstrated that compounds interact strongly with the HSA with a static quenching mechanism. Our evaluation of the cytotoxicity of complexes against the breast cancer MCF-7 cell line showed that complex 2 presents a better cytotoxicity than the standard cis-Pt. Finally, using the AutoDock 4.2 program, simulations to analyze the mechanism of complex–HSA interactions and their binding mode were carried out. Results showed that the best binding mode is located in subdomain IB for 1, 2, and 4, in I/II for 3, and in IA/IIA for 5.

Communicated by Ramaswamy H. Sarma

Keywords:

• Coordination compounds
• deferiprone
• human serum albumin
• breast cancer
• MCF-7 cells

Acknowledgements

We thank the Cambridge Crystallographic Data Center for access to the CSD Enterprise.

Disclosure statement

No potential conflict of interest was reported by the author(s). 

Additional information

Funding

This work was funded by Ferdowsi University of Mashhad [Grant number: 3/39773] and Mashhad University of Medical Sciences, Iran. The crystallographic part was supported by the project 18-10504S of the Czech Science Foundation and by Operational Programme Research, Development and Education financed by European Structural and Investment Funds, and the Czech Ministry of Education, Youth and Sports [Project No. SOLID21 CZ.02.1.01/0.0/0.0/16_019/0000760].