1. Natural Products Research Institute, College of Pharmacy, Seoul National University, San 56-1, Sillim, Seoul 151-742, Korea, Marine Natural Products Laboratory, Korea Ocean Research and Development Institute, Ansan P.O. Box 29, Seoul 425-600, Korea, Department of Biological Science, College of Life Science and Nano Technology, Hannam University,461-6 Jeonmin, Yuseong, Daejeon 305-811, Korea, and Department of Agricultural Biotechnology, College of Agriculture and Life Science, Seoul National University,...