1. Department of Chemistry, Institute of Physical, Nuclear and Macromolecular Chemistry and Scientific Center of Materials Science, Philipps-University Marburg, Hans-Meerwein-Str., D-35039 Marburg, Germany, School of Medicine, Department of Pharmacology and Toxicology, Philipps-University Marburg, Karl-von-Frisch-Str. 1, D-35033 Marburg, Germany, and Department of Pharmaceutical Technology and Biopharmacy, Philipps-University Marburg, D-35032 Marburg, Germany