1. Max Planck Institute of Molecular Physiology Department of Chemical Biology Otto-Hahn-Straße 11 44227 Dortmund Germany
2. Ruhr University Bochum Department of Organic Chemistry Universität Straße 150 44801 Bochum Germany
3. Technical University Dortmund Faculty of Chemical Biology Otto-Hahn-Straße 4a 44227 Dortmund Germany