1. Department of Chemistry Scripps Research 10550 North Torrey Pines Road La Jolla CA 92037 USA
2. Laboratorium für Organische Chemie ETH Zürich Vladimir-Prelog-Weg 3, HCI 8093 Zürich Switzerland
3. Science and Innovation Center Mitsubishi Chemical Corporation 1000, Kamoshida-cho, Aoba-ku Yokohama Kanagawa 227-8502 Japan
4. AbbVie Process Research and Development 1401 North Sheridan Road North Chicago IL 60064 USA