Synthesis, characterization and antibacterial activity of nickel (II) and copper (II) complexes of N-(alkyl(aryl)carbamothioyl)-4-nitrobenzamide

Abstract

Nickel and copper metal complexes of N-(R-carbamothioyl)-4-nitrobenzamide (R = diphenyl and ethylbutyl) were synthesized and characterized by IR, ¹H NMR, mass spectrometry and elemental analysis. The spectroscopic data are consistent with the ligand and the metal complexes containing two O and S chelated ligands. N-(diphenylcarbamothioyl)-4-nitrobenzamide, HL¹, was characterized by a single crystal X-ray diffraction study. It crystallizes in the triclinic space group P with unit cell dimensions of a = 6.8044(4) Å, b = 10.0113(6) Å, c = 13.2365(8) Å, α = 6.8044(4) °, β = 78.171(4) °, γ = 13.2365(8)°, V = 882.43(9) ų. The ligands coordinate as bidentates yielding essentially neutral complexes of the type [ML₂]. The ligands and complexes were screened for their in vitro antibacterial activities and comparatively the complexes showed greater antibacterial efficacy than the thiourea derivative ligands.