1. Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan, RIKEN Harima Institute/SPring-8, Koto 1-1-1, Mikazukicho, Sayo-gun, Hyogo 679-5148, Japan, and Department of Bioresources Chemistry, Faculty of Horticulture, Chiba University, Matsudo 271-8510, Japan