1. Laboratory of Aquatic Natural Products Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
2. Faculty of Advanced Life Science, Frontier Research Center for Advanced Material and Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo, Hokkaido 001-0021, Japan
3. Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
4. JEOL RESONANCE, Inc., 3-1-2 Musashino, Akishima, Tokyo 196-8558, Japan
5. Sesoko Station, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
6. Graduate School of Fisheries Science and Environmental Studies, Nagasaki University, Nagasaki, 852-8521, Japan