1. Laboratory
for Bioorganic Chemistry, Sloan-Kettering Institute for Cancer Research, 1275
York Avenue, New York, New York 10065, United States
2. Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, 51 Blossom
Street, Boston, Massachusetts, United States
3. Department of Chemistry, Columbia University, Havemeyer Hall, 3000 Broadway,
New York, New York 10027, United States