1. Institute of Organic Chemistry, University of Würzburg, Am Hubland, Würzburg 97074, Germany
2. Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, Göttingen 37073, Germany
3. Göttingen Center for Molecular Biosciences, Georg-August University Göttingen, Justus-von-Liebig-Weg 11, Göttingen 37077, Germany
4. Center for Nanosystems Chemistry, University of Würzburg, Theodor-Boveri-Weg, Würzburg 97074, Germany