Copper(II) Complexes of 2-(Methylthiomethyl)anilines: Spectral and Structural Properties and In Vitro Antimicrobial Activity

Copper(II) complexes of 2-(methylthiomethyl)anilines (1a–1f) have been obtained and characterized by elemental analyses, IR, electronic spectra, conductivity, and X-ray crystallography. The complexes (2a–2f) have the structural formula [CuCl2L] with the bidentate ligand coordinating through sulfur and nitrogen. The single crystal X-ray diffraction data reveal that the copper complex (2f) has a tetragonally distorted octahedral structure with long Cu–Cl equatorial bonds. Magnetic susceptibility measurements indicate the availability of one unpaired electron in the complexes and the conductivity measurements in DMF show their behaviour as nonelectrolytes. The solid reflectance spectra and the electronic spectra of the complexes in DMSO were determined. The ligands and their copper complexes were screened for in vitro antimicrobial activity against S. aureus, B. subtilis, E. coli, and C. albicans. The methoxysubstituted complex (2c) showed more promising antibacterial activity against S. aureus and B. subtilis than other compounds at the concentration tested