Study molecular modeling and the effect of some biological metals on the efficiency of norfloxacin in presence of 3-(bromoacetyl)coumarin

A series of new mixed ligand metal complexes of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized by the reaction of norfloxacin (NOR) with 3-(bromoacetyl)coumarin (BAC) in 1:1:1 (Mn+:NOR:BAC) molar ratio, which characterized by elemental analysis, spectroscopic measurements (FT-IR, UV-Vis) molar conductance, effective magnetic moments, and thermogravimetric analysis (TG) and (DTG). All the complexes soluble in DMSO and the conductivity measurement indicate that the complexes are electrolyte with ratio 1:1 for Mn(II), Fe(II), and Zn(II) and 1:2 for Co(II), Ni(II), and Cu(II). Electronic and magnetic data elucidated the octahedral structure for all complexes. Assorted thermodynamic factors are calculated, and the results are explicated. Molecular modeling calculations (bond angles, dihedral angles, total energy, heat of formation, and dipole moment) confirm the structural geometry of the complexes and indicate the very good agreement between the computed and experimental geometrical parameters. The calculated data for the hardness (eta) and absolute softness (sigma) showed that all complexes are soft with respect to ligands. The two ligands and their metal complexes have also been screened for their antibacterial and antifungal activity against some selected species; the data showed that the complexes have remarkable potency as compared with the parent ligands.