Synthesis, crystal structure, and urease inhibition of an end-on azido-bridged dinuclear copper(II) complex with an oxidized tridentate Schiff base ligand.

An end-on azido-bridged dinuclear copper(II) complex, [Cu2L2(μ1,1-N3)2], where L is the deprotonated form of N-(2-hydroxy-4-methoxybenzylidene)picolinamide (HL), has been prepared by the reaction of 5-methoxy-2-[(pyridin-2-ylmethylimino)methyl]phenol (HL′) with copper bromide and sodium azide in methanol. The structure of the complex was characterized by elemental analysis, IR and UV–vis spectra, and single crystal X-ray diffraction. The complex possesses crystallographic inversion symmetry, with the two Cu ions (3.36 Å) bridged by two end-on azido bridges. Each Cu ion is in a square pyramidal coordination. The original ligand HL′ was unexpectedly oxidized to HL under mild conditions during preparation of the complex. The complex has excellent urease inhibitory activity. [ABSTRACT FROM AUTHOR]