1. Kyushu National Industrial Research Institute, Shuku-machi, Tosu, Saga 841, Japan, Institute of Biophysics, Faculty of Agriculture, Kyushu University, Higashi-ku, Fukuoka 812-81, Japan, Department of Chemistry and Biochemistry, University of Windsor, Ontario N9B3P4, Canada, and Faculty of Pharmaceutical Science, Kyushu University, Maidashi, Higashi-ku, Fukuoka 812-81, Japan