Spectral characterization, DFT, docking and cytotoxicity of N-benzyl-4,5-dihydro-3-methyl-5-oxo-1H-pyrazole-4-carbothioamide and its metal complexes

Abstract

A new ligand N-benzyl-4,5-dihydro-3-methyl-5-oxo-1H-pyrazole-4-carbothioamide (H2L) and some of its divalent metal complexes were synthesized. Elemental analyses, mass spectra (MS), 1H and 13Cnuclear magnetic resonance, electronparamagnetic resonance (EPR), infrared spectra (IR), ultra-violet and visible spectra, thermogravimetric analyses (TGA) and the effective magnetic moments were used in characterization of the isolated compounds. The ligand (H2L) was geometry optimized by density function theory. The vibrational spectra of the optimized H2L was calculated and compared with the observed spectra. There was a good agreement between the theoretically calculated and the experimental vibrational spectra. Tetrahedral stereochemistries were suggested for Co(II), Ni(II) and Zn(II) complexes while, square planar stereochemistry was suggested for Cu(II) complex. Molecular docking was carried out to indicate the interaction between the tested compounds and the studied protein. Molecular docking was able to predict the anticancer activities of the ligand and its complexes.The cytotoxicity of the ligand and its complexes was tested on Helacell line. The ligand showed strong cytotoxicity while, the metal complexes had moderate.