Preparation and structural characterization of oxovanadium(V) complexes with Schiff bases and their inhibition studies on Helicobacter pylori urease

Abstract

A series of structurally similar dinuclear oxovanadium(V) complexes, [VO₂L]₂ (L = L¹ = 2-[(2-methylaminoethylimino)methyl]phenolate (1); L = L² = 2-[(2-ethylaminoethylimino)methyl]phenolate (2); L = L³ = 2-[(2-isopropylaminoethylimino)methyl]phenolate (3)), has been synthesized and characterized by physico-chemical methods and single-crystal X-ray diffraction. The V in each complex is octahedral, with three donors of L and one oxo defining the equatorial plane, and with two oxos occupying the axial positions. The complexes were tested for their urease inhibitory activities. The inhibition rate (%) of 1, 2, and 3 at 100 µmol L⁻¹ on urease are 67 ± 1, 53.5 ± 0.9, and 44 ± 1. The relationship between structures of the complexes and the urease inhibitory activities indicates that shorter terminal groups of the complexes have stronger activities against urease. Molecular docking study of the complexes with the Helicobacter pylori urease was performed.

Keywords:

• Schiff base
• Oxovanadium(V) complex
• Crystal structure
• Urease inhibition

Acknowledgments

This work was financially supported by the National Science Foundation of China (Project No. 20901036).