1. Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
2. Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K.
3. Institute for Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
4. RD&C Research, Development & Consulting GmbH, 1170 Vienna, Austria
5. Department of Pharmacy, Ludwig-Maximilians-Universität, 81377 Munich, Germany