Clioquinol, a Drug for Alzheimer's Disease Specifically Interfering with Brain Metal Metabolism: Structural Characterization of Its Zinc(II) and Copper(II) Complexes

Clioquinol, a 8-hydroxyquinoline derivative, is producing very
encouraging results in the treatment of Alzheimer's disease (AD).
Its biological effects are most likely ascribed to complexation of
specific metal ions, such as copper(II) and zinc(II), critically
associated with protein aggregation and degeneration processes
in the brain. We report here, for the first time, a structural
characterization of the zinc(II) and copper(II) complexes of
clioquinol. A ligand to metal stoichiometry of 2:1 is found in both
cases, though in the presence of quite different coordination
polyhedra. The present findings are discussed in the frame of
modern approaches to AD treatment.