Synthesis, crystal structures and Jack bean urease inhibitory activity of copper(II) complexes with 4-bromo-N′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide

Abstract

A new hydrazone 4-bromo-N′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide (HL) was prepared and characterized by infrared and UV–vis spectra, as well as single-crystal X-ray diffraction. With the hydrazone as ligand, two new copper(II) complexes were prepared, [Cu₂L₂(NCS)₂]·4H₂O (1) and [CuBrL]·CH₃OH (2). The complexes were characterized by infrared and UV–vis spectra, and single-crystal X-ray diffraction. The Cu in 1 is in a square pyramidal coordination geometry and that in 2 is in a square planar coordination geometry. The two complexes show effective Jack bean urease inhibitory activity, with IC₅₀ values of 23.5 and 2.7 μM, respectively. A molecular docking study of 2 with the urease was performed. The relationship between the structure and urease inhibitory activity indicated that copper complex with square planar coordination is a better model for urease inhibition.

Keywords:

• Hydrazone
• copper complex
• crystal structure
• urease inhibition
• molecular docking