Structural and biological studies of mononuclear metal (II) complexes containing hetero ligand based on 3‐acetylpyridine thiosemicarbazone

Abstract

The Schiff base (3‐APT) was a bidentate ligand produced from the condensation between 3‐acetylpyridine and the amine group of thiosemicarbazide. Metal chelates were successfully obtained with formulas [Cu(3‐APT)2X]X, [Ni(3‐APT)2]X2.H2O and [Pd(3‐APT)X2] (where 3‐APT = 3‐acetylpyridine thiosemicarbazone and X = Cl−). The characterization was performed by various physicochemical tools. The studied (3‐APT) ligand had two donor sites through both azomethine nitrogen and thiocarbonyl sulfur. The characterization tools observed the presence of two different geometric shapes. The square planar structure in the case of both nickel (II) and palladium (II) chelates and the square pyramidal structure in the case of copper (II) complex. The characterization involved a 1HNMR study for the (3‐APT) ligand and its square planar Pd (II) and Ni (II) chelates. The density functional theory was used to structurally optimize the synthesized ligand and its chelates. The antibacterial activity was evaluated using different types of bacteria showing superior results. The breast (MCF‐7) cell line was selected to investigate the cytotoxic effect of formed compounds. The palladium (II) complex was the most cytotoxic effective compound with the least IC50 value. Further theoretical molecular docking study was performed to observe the active sites in the selected proteins during their interactions with our compounds.