1. Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
2. Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
3. Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
4. Center for NMR Spectroscopy, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
5. Center for X-ray Crystallography, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States