1. Department of Pharmaceutical Sciences, College of Pharmacy, The University of Michigan, 428 Church Street, Ann Arbor, Michigan 48109, Exploratory Biopharmaceutics and Stability, Pharmaceutical Research Institute, Bristol-Myers Squibb Company, One Squibb Drive, P.O. Box 191, New Brunswick, New Jersey 08903, Laboratory of Metabolism, Building 37, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, and TSRL Inc., 540 Avis Drive, Suite A, Ann Arbor, Michigan 48108