1. Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
2. Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United States
3. Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States