1. Department of Chemistry, Tennessee Technological University, Cookeville, Tennessee 38505, United States
2. Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, Nashville, Tennessee 37204-3951, United States
3. Department of Chemistry, Georgia College, Milledgeville, Georgia 31061, United States
4. Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States