1. Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
2. Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
3. Institute of Organic Chemistry at Leopold Franzens University, A-6020 Innsbruck, Austria
4. Department of Chemistry, Yale University, New Haven, CT 06520, USA
5. Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60607, USA