Spectral, optical, and cytotoxicity studies on N‐(2‐isonicotinoylhydrazine‐carbonothioyl)benzamide and its metal complexes

The ligand N‐(2‐isonicotinoylhydrazine‐carbonothioyl)benzamide (H3L) and its metal complexes with Co(II), Ni(II), Cu(II), and Zn(II) acetates have been synthesized. The synthesized compounds have been characterized by elemental analyses, FT‐IR, UV‐Visible spectra, 1H‐NMR, 13C‐NMR, ESR, MS, effective magnetic moments, molar conductance, and thermal analyses. The free organic ligand exists in the keto form, but in the metal complexes, it forms chelates with the metal ions in the enol form. The measured optical band gap (Eg) values confirmed the presence of direct electronic transition and the semiconductivity of the current compounds. The ligand and its Zn(II) complex were examined as cytotoxic agents against HePG‐2 and HCT‐116 and showed. H3L exhibited strong cytotoxicity, while Zn complex showed moderate activity.