1. Department of Biochemistry, Vanderbilt University School of Medicine, 2215 Garland Avenue, 607 Light Hall, Nashville, Tennessee 37232-0146, United States
2. Discovery Research, Boehringer Ingelheim Regional Center Vienna GmbH & Co KG, 1120 Vienna, Austria
3. Molecular Design and Synthesis Center, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37323-0146, United States
4. Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, Maryland 21701-4907, United States