Synthesis, Crystal Structures and Urease Inhibition of Zinc Complexes Derived from 4-Chloro-2-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)phenol

Abstract

Three new zinc(II) complexes, [Zn₃(μ₂-η¹:η¹-OAc)₂(μ₂-η²:η⁰-OAc)₂L₂] (1), [Zn₃(μ₂-η¹:η¹-OAc)₂(μ_1,1-N₃)(N₃)L₂] (2), [Zn₂(μ_1,3-N₃)(N₃)(H₂O)L₂] (3), with the Schiff base ligand 4-chloro-2-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)phenol (HL) have been synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopic studies. Crystal structures of the complexes were confirmed by single crystal X-ray diffraction. Complex 1 is a bidentate acetato, monoatomic bridging acetato, and phenolato co-bridged trinuclear zinc compound. The Zn atoms are in octahedral and square pyramidal coordination. Complex 2 is a bidentate acetato, end-on azido, and phenolato co-bridged trinuclear zinc compound. The Zn atoms are in trigonal bipyramidal and square pyramidal coordination. Complex 3 is an end-to-end azido bridged dinuclear zinc compound. The Zn atoms are in square pyramidal and trigonal bipyramidal coordination. The Schiff base ligands in the complexes coordinate to the Zn atoms through the phenolate oxygen, imino nitrogen and pyrrolidine nitrogen. The complexes have interesting inhibitory activity on Jack bean urease, with IC₅₀ values of 7.1–15.3 μmol·L^–1.