Synthesis, Characterization, Crystal Structures, and in vitro Antitumor Activity of Palladium and Platinum (Ii) Complexes with 2-Acetyl-4-Methylthiazole Thiosemicarbazone and 2-Acetylpyrazine Thiosemicarbazone

Abstract

The novel Schiff bases I HAMTTSC (2-Acetyl-4-methylthiazole thiosemicarbazone), II HAPTSC(2-Acetylpyrazine thiosemicarbazone) and their complexes with Pt(II) and Pd(II): 1 [Pt(AMTTSC)Cl], 2 [Pt(AMTTSC)2], 3 [Pd(AMTTSC)Cl], 4 [Pd(AMTTSC)2], 5 [Pt(APTSC)Cl], 6 [Pt(APTSC)2], 7 [Pd(APTSC)Cl], and 8 [Pd(APTSC)2] have been synthesized, and characterized by elemental analysis and spectroscopic studies. The crystal structure of the Schiff bases I, II, and the complex 1 [Pt(AMTTSC)Cl], have been solved by single-crystal X-ray diffraction. The electronic, IR, UV/Vis, and NMR spectroscopic data of I and II and their complexes are reported. The in vitro antitumor activity of the Schiff bases and 1, 2, 4, 5 and 6 complexes against two different human tumor cell lines (HT-29 and HuTu-80) reveals that the complexes are more cytotoxic than their corresponding ligands with IC50 values at the range of 0.1-10 ?M. These compounds can therefore be considered as agents with potential antitumor activity. Molecular structure of 1 [Pt(AMTTSC)Cl]