Synthesis, characterization, molecular docking and cytotoxicity studies on N-benzyl-2-isonicotinoylhydrazine-1-carbothioamide and its metal complexes

N-benzyl-2-isonicotinoylhydrazine-1-carbothioamide (H3L) and its complexes with Co(II), Ni(II), Cu(II) and Zn(II) have been synthesized. The metal complexes have been characterized by elemental and thermal analyses, spectral studies of FT-IR, H-1 and C-13 NMR, ESR, MS, and UV-Visible, conductance and magnetic moments measurements. The free ligand exists in the keto-thione form, but it coordinates to the metal ion in the keto-thiol form. The 1:1 coordinated species, M(II)-H3L, are formed. The optical band gap (E-g) measurements indicated direct electronic transition and semi-conducting nature of the compounds. The cytotoxicity of H3L and its Zn(II) complex were tested against both HCT116 and HePG2. The ligand showed strong cytotoxicity against the two investigated cell lines, while Zn(II) complex exhibited moderate cytotoxic effect. The molecular docking on both colon and liver cancer proteins were studied and the data support the experimental results. (C) 2019 Elsevier B.V. All rights reserved.