Synthesis, X-ray crystal structure and cytotoxicity studies of zinc(II) and cadmium(II) iodide complexes with antipyrine

Abstract Molecular complex [Zn(AP)2I2] (1) and the isomorphous ones [Cd(AP)6][Cd(AP)X3]2 consisting of octahedral complex cations [Cd(AP)6]2+ and the respective complex anions [Cd(AP)X3]− (AP – antipyrine, 2,3-dimethyl-1-phenyl-3-pyrazolin-5-one; X = I (2) or Br(3)) were prepared and characterized by single crystal X-ray diffraction, IR vibrational spectroscopy, thermal analysis and DFT calculations. It was found that antipyrine molecules are coordinated by the metal atom, in both zinc-containing molecular complex (1) and in the cadmium-containing complex cations and anions (compounds (2) and (3)), via an oxygen atom of the ligand carbonyl group. The experimental results confirm the calculated ones. Both zinc (cadmium) iodides and their antipyrine complexes demonstrate cytotoxic activity in vitro at 10−5–10−3 mol/L, and are promising ones for further investigations of their anticancer activity both in vitro and in vivo.