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

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 μM. These compounds can therefore be considered as agents with potential antitumor activity. Molecular structure of ...