1. Department of Chemistry; University of Sheffield; Brook Hill Sheffield S3 7HF UK
2. Institute of Organic Chemistry; Karlsruhe Institute of Technology; Fritz-Haber-Weg 6 76131 Karlsruhe Germany
3. Cynora GmbH; Werner-von-Siemens-Straße 2-6 76646 Bruchsal Germany
4. Departamento de Química Organica I; Universidad del País Vasco; Manuel Lardizabal 3 20018 San Sebastian Spain
5. Institute of Toxicology and Genetics; Karlsruhe Institute of Technology; Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany