Abstract
The reaction of bromazepam (7‐bromo‐1,3‐dihydro‐5‐(2‐pyridyl)‐2H‐1,4‐benzodiazepin‐2‐one, BZM) with Cr(III) (1), Fe(III) (2) and Ru(III) (3) salts gives complexes of the type [M(BZM)3]⋅3X (X = Cl or NO3). Structural characterization was extensively carried out using various analytical and spectral tools such as infrared, 1H NMR and UV–visible spectroscopies and magnetic, conductance, elemental and thermal analyses. BZM is a bidentate ligand and interacts with the metal ions via the pyridine and benzodiazepin‐2‐one nitrogen atoms. The magnetic and electronic properties of 2 and 3 are consistent with low‐spin octahedral complexes. The three BZM molecules are non‐isoenergetically coordinated to the metal ions and this is reflected in the values of the second‐order interaction energy. The antibacterial activity was studied using Staphylococcus aureus and Escherichia coli. Coordination of BZM to Cr(III) or Ru(III) ions leads to a marked increase in toxicity with respect to the inactive Fe(III) complex 2.
Structures of Cr(III), Fe(III) and Ru(III) complexes of the anti‐anxiety drug bromazepam (BZM) have been experimentally and theoretically studied. The susceptibility of Staphylococcus aureus and Escherichia coli towards BZM and its complexes has been evaluated. Low‐spin octahedral geometry is suggested for the Fe(III) and Ru(III) complexes. The three BZM molecules are non‐isoenergetically coordinated to the metal ions and this is reflected in the values of the second‐order interaction energy.