1. Natural Products Laboratory, Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, Biotech Research Laboratories, 1600 East Gude Drive, Rockville, Maryland 20850, Kyoto Pharmaceutical University, Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607, Japan, College of Pharmacy, Nihon University, Narashinodai, Funabashi, Chiba 274, Japan, Tokyo Metropolitan Govern Research Laboratory of Public Health, Hyakunin-cho, Shinjuku-ku,...