A new Pd(II) complex with an adamantane-derived Schiff base: synthesis and preliminary antitumor studies

Since the introduction of platinum-based chemotherapy, transition-metal complexes have attracted considerable interest as anticancer agents. Among them, Pd(II) complexes have emerged as promising alternatives due to their chemical similarity to Pt(II) compounds, with recent clinical advances. In this work, a novel palladium(II) complex containing an adamantane-derived Schiff base was synthesized and preliminarily evaluated for its biological activity. The ligand was obtained by condensing amantadine with 2-thiophenecarboxaldehyde, followed by complexation with Li₂PdCl₄, producing the complex [PdC₁₅H₁₉Cl₂NS] in 85.5% yield. Spectroscopic analyses indicated a square-planar Pd(II) center coordinated through the imine nitrogen and thiophene sulfur atoms. Preliminary in vitro assays demonstrated antiproliferative activity against hypopharyx carcinoma (FaDu) cells, while no cytotoxicity was observed toward non-tumoral HaCaT keratinocytes. These findings highlight Pd-atdTiof as a promising candidate for further investigation as a potential anticancer agent.