1. Departments of Chemistry, University of California, Irvine, Irvine, California 92697-3900, United States
2. Departments of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, California 92697-3900, United States
3. Departments of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697-3900, United States