1. Laboratory of Natural Product Chemistry, Division of Fundamental AgriScience Research, Research Faculty of Agriculture, Hokkaido University, Kita-9, Nishi-9, Sapporo 060-8589, Japan
2. Frontier Research Center for Advanced Material and Life Science, Faculty of Advanced Life Science, Hokkaido University, Kita 21, Nishi 11, Sapporo 001-0021, Japan
3. Department of Nutritional Science, Faculty of Applied BioScience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan