Ruthenium(II) Phosphinic Acyltiourea Complexes with Potent Cytotoxic Activity

Cancer remains a global challenge characterized by uncontrolled cell growth and metastasis, prompting research into coordinating bioactive molecules to metal centers to enhance their therapeutic effects. This study synthesized and characterized four novel ruthenium(II) complexes using structurally versatile acylthiourea ligands. Biological evaluations revealed that these complexes have a moderate binding affinity to human serum albumin driven by hydrophobic interactions, alongside weak electrostatic interactions with DNA. Notably, all complexes demonstrated significantly higher cytotoxicity against lung and breast cancer cell lines than both the free ligands and the standard chemotherapy drug cisplatin. Among them, the complex designated as Ru2 emerged as the most promising candidate; it exhibited exceptional potency against lung cancer cells, a high selectivity index of 16, and effectively altered cell morphology while inhibiting cell migration. Overall, these ruthenium(II) acylthiourea complexes show great potential as highly effective agents for target-oriented cancer therapy.