Second-Coordination-Sphere Effects Increase the Catalytic Efficiency of an Extended Model for FeIIIMII Purple Acid Phosphatases

Herein we describe the synthesis of a new heterodinuclear FeIIICuII model complex for the active site of purple acid phosphatases and its binding to a polyamine chain, a model for the amino acid residues around the active site. The properties of these systems and their catalytic activity in the hydrolysis of bis­(2,4-dinitrophenyl)­phosphate are compared, and conclusions regarding the effects of the second coordination sphere are drawn. The positive effect of the polymeric chain on DNA hydrolysis is also described and discussed.