1. Molecular Recognition Section, Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, Maryland 20892-0810, United States
2. Department of Pharmacology, University of North Carolina, School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
3. Laboratory of Biological Modeling, NIDDK, National Institutes of Health, Bethesda, Maryland 20892, United States