1. Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
2. Molecular Structures Group, Nuclear Magnetic Resonance Laboratory, The University of Kansas, Lawrence, Kansas 66045, United States
3. Department of Medicinal Chemistry, The University of Kansas, Lawrence, Kansas 66045, United States
4. Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
5. Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States