1. Bioorganic Research Institute Suntory Foundation for Life Sciences 8-1-1 Seikadai, Seika-cho, Soraku-gun Kyoto 619-0284 Japan
2. Department of Biological Chemistry and Food Sciences Faculty of Agriculture Iwate University 3-18-8 Ueda Morioka Iwate 020-8550 Japan
3. Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan