1. PharmaCenter Bonn, Pharmaceutical Institute, Department of Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
2. Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Deutscher Platz 5, D-04103 Leipzig, Germany
3. Institute of Cell Biology and Neuroscience, Goethe-University, D-60438 Frankfurt am Main, Germany