1. Research and Development Division, Oryza Oil & Fat Chemical Company, Ltd., 1 Numata Kitagata-cho, Ichinomiya, Aichi 493-8001, Japan; Kyoto Pharmaceutical University, 1 Shichono-cho, Yamashina-ku, Kyoto 607-8412, Japan; and School of Pharmacy, Department of Biological Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Okayama 703-8516, Japan