Structural Model for the Cu_B Site of Dopamine β-Hydroxylase: Crystal Structure of a Copper(II) Complex Showing N₃OS Coordination with an Axial Sulfur Ligation

Abstract

A copper(II) complex containing a NSO-donor Schiff base and NN-donor 2,2‘-bipyridine has been prepared and structurally characterized. The square pyramidal complex with an axial sulfur ligation is a structural model for the CuB site of dopamine β-hydroxylase in its oxidized form. The copper(II) complex is catalytically active in the oxidation of ascorbic acid by dioxygen mediated by a copper(I) species which is proposed to have a four-coordinate structure with a N3S coordination geometry.