1. Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Japan
2. Graduate School of Biomedical Sciences, Nagasaki University, Bunkyo-machi, Japan
3. Kunming Institute of Botany, Chinese Academy of Science, China
4. Department of Chemistry, Rikkyo University, Nishi-Ikebukuro, Toshima-ku, Tokyo, Japan