Orthopalladated tetralone oxime compounds bearing tertiary phosphines: Synthesis, structure, biological and in silico studies

• Antitumor properties of four new mononuclear cyclopalladated were investigated. • All compounds were more active than cisplatin on MCF-7 cancer cells. • DNA binding studies suggests weakly interactions. • HSA binding spectroscopy and in silico studies indicates interactions in DS1. The halido-α-bridge cleavage reactions between [Pd( C 2 ,N -tetrox)(μ-Cl)] 2 precursor (tetrox = E- α-tetralone oxime) with phosphines, in 1:2 molar ratio, have afforded mononuclear cyclopalladated compounds of the type [PdCl( C 2 ,N -tetrox)(L)] { L = triphenylphosphine ( 1 ); tris(4-methylphenyl)phosphine ( 2 ); tris(4-fluorophenyl)phosphine ( 3 ) and tris(4-methoxyphenyl)phosphine ( 4 )}. The compounds have been characterized by elemental analyses, infrared (FT-IR) and 1 H, 13 C{ 1 H} and 31 P{ 1 H}-NMR spectroscopies. The molecular structure of 3 has been determined by single crystal X-ray diffraction (SC-XRD) and the Hirshfeld Surface calculation (HS) has been performed. The antiproliferative activity of compounds 1–4 has been evaluated against breast (MCF-7) and lung (A549) human cancer cells, and human lung fibroblast (MRC-5). All cyclopalladated compounds have been more active than cisplatin against MCF-7 cells, with IC 50 values ranging from 19 to 26 µM. Binding experiments involving compound 3 with ct-DNA and human serum albumin (HSA) have been carried out using spectroscopic techniques. The interaction between compound 3 and HSA has been studied by means of molecular docking.