1. The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
2. Department of Chemistry, State University of New York at Cortland, Cortland, New York 13045, United States
3. NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Argonne, Illinois 60439, United States
4. Department of Chemistry, the College of Wooster, Wooster, Ohio 44691, United States