Synthesis, Structural Features, and Antiproliferative Activity of Heteroligand Palladium(II) Complex Containing an Acyclic Diaminocarbene Ligand

This article presents the synthesis and detailed structural investigation of a new palladium (II) heteroligand complex trans-PdCl (CNXyl) 2 (CCN (H) Xyl2) Cl, containing an acyclic diaminocarbene ligand and two isocyanide ligands. X-ray diffraction and NMR spectroscopy revealed that complex is stabilized both in the crystal and in solution by a system of N–H···Cl– hydrogen bonds formed between one chloride anion and two N–H groups of the diaminocarbene ligand (N–H···Cl–···H–N), with calculated energies of 3. 8–5. 4 kcal/mol. A Cambridge Structural Database search identified 22 other palladium (II) acyclic diaminocarbene complexes with similar N–H···X···H–N (X = Cl–, Br–, O=C<, O=S<, etc. ) hydrogen-bonded systems. The complex demonstrated significant antiproliferative activity against the triple-negative breast cancer cell line MDA-MB-231, with an IC50 value of 5. 55 ± 0. 45 µM, which is four times higher than that of cisplatin.