摘要
Eight diiron_((I))bis-cyclopentadienyl complexes with a bridging methylthiocarbyne ligand were prepared from the tris-carbonyl precursor[Fe_(2)Cp_(2)(CO)_(2)(μ-CO)(μ-CSMe)]CF_(3)SO_(3)(Cp=η^(5)-C_(5)H_(5))through the substitution of one or two terminal carbonyls with a variety of monodentate ligands including phosphanes/phosphite,alkyl/aryl isocyanides or iodide.All compounds were isolated in 57-84%yield and characterized by IR and multinuclear NMR spectroscopy and by X-ray diffraction in five representative cases.Their bonding,stereochemistry and isomerization processes were investigated by NMR and DFT techniques.The water solubility and octanol-water partition coefficient heavily depend on the different monodentate ligands.All cationic complexes displayed substantial inertness in aqueous and cell culture medium solutions at 37℃over 24-48 h.Their cytotoxicity was assessed on a panel of human cancer cell lines(HCT 116,MCF-7 and A2780).Four compounds showed IC_(50) values down to the nanomolar range in colorectal,breast and ovarian cancer cell lines.The most potent compound,[Fe_(2)Cp_(2)(CO)(PPh_(3))(μ-CO)(μ-CSMe)]CF_(3)SO_(3),revealed enhanced Fe accumulation and significant disruption of cell redox homeostasis in A2780 cells that resulted in caspase-independent apoptotic cell death.The six times higher sensitivity of A2780 cells in comparison to healthy fibroblasts(MRC-5)underlines the potential of this compound to preferably target cancer cells.Overall,the variation of monodentate ligands on a diiron_((I))bis-cyclopentadienylμ-thiocarbyne core represents a simple strategy to obtain robust compounds with tuneable physico-chemical properties and possibly also a remarkable anticancer activity.
基金
support from the University of Pisa under the“PRA 2022-2023-Progetti di Ricerca di Ateneo”(Institutional Research Grants)-Project no.PRA_2022_12“New challenges of transition metal and lanthanide complexes in the perspective of green chemistry”
the Ministry of Science,Technological Development,and Innovation of the Republic of Serbia(No.451-03-136/2025-03/200007)for the financial support.
