1. Institute of Pharmaceutical Chemistry, Biocenter, Institute of Pharmacology, Biocenter, and Institute of Pharmaceutical Biology, Biocenter, J.W. Goethe-University, Marie-Curie-Strasse 9, 60439 Frankfurt, Germany, Institute for Marine Biosciences, National Research Council, 1411 Oxford St., Nova Scotia B3H 3Z1, Canada, and Socra Tec R&D GmbH, Feldbergstrasse 59, 61440 Oberursel, Germany