1. Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
2. Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA.
3. Moores Cancer Center, University of California San Diego, La Jolla, CA 92093, USA.
4. Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA 92093, USA.
5. Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA.
6. Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA.
7. Department of Pharmacology, University of California San Diego, La Jolla, CA 92093, USA.
8. Departments of Biological Sciences and of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA.