1. Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan, CPI Company, Daicel Chemical Industries, Ltd., Shinko-cho, Myoko, Niigata 944-8550, Japan, and CPI Company, Daicel Chemical Industries, Ltd., Aboshi, Himeji, Hyogo 671-1283, Japan