Affiliation: | 1. Department of Medicinal Chemistry, MRL, Merck & Co., Inc., PO Box 4, West Point, PA 19486, USA;2. Department of Pain Research, MRL, Merck & Co., Inc., PO Box 4, West Point, PA 19486, USA;3. Department of Drug Metabolism, MRL, Merck & Co., Inc., PO Box 4, West Point, PA 19486, USA |