1. Leibniz-Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Beutenbergstrasse 11a, D-07745 Jena, Germany, Max-Planck-Institute for Chemical Ecology, D-07745 Jena, Germany, Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Germany, and Institute for Organic Chemistry, Johannes Gutenberg University Mainz, Germany