1. Department of Pharmaceutical and Medicinal Chemistry; Pharmaceutical Institute of the Christian Albrechts University in Kiel; Gutenbergstraße 76 24118 Kiel Germany
2. Department of Pharmacy, Center for Drug Research; Pharmaceutical Biology; University of Munich; Butenandtstraße 5-13 81377 Munich Germany
3. Department of Food Chemistry and Toxicology; University of Vienna; Währinger Straße 38 1090 Vienna Austria