1. Francis Bitter Magnet Laboratory, Department of Chemistry, Massachusetts Institute of Technology, 170 Albany Street, Cambridge, MA 02139 (USA)
2. Bruker BioSpin Corporation, 15 Fortune Drive, Billerica, MA 01821 (USA)
3. Current address: Amgen Inc., 360 Binney Street, Cambridge, MA 02142 (USA)
4. Tianjin Key Laboratory on Technologies Enabling, Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin 300070 (China)
5. Center for Biomedical EPR Spectroscopy and Imaging, Davis Heart and Lung Research Institute and Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH 43210 (USA)
6. Current address: Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, MA 02210 (USA)
7. NMR Spectroscopy, Department of Chemistry, Faculty of Science, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht (The Netherlands)