1. Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
2. Tri-Institutional Program in Chemical Biology, Cornell University, 1300 York Avenue, New York, New York 10065, United States
3. Department of Pharmacology, Weill Medical College of Cornell University, 1300 York Avenue, New York, New York 10065, United States
4. Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States