1. Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan, Research Institute, Meijo University, Shiogamaguchi 1-501 Tempaku, Nagoya 468-8502, Japan, and Department of Chemistry, Faculty of Science, Yamaguchi University, Yoshida 1677-1, Yamaguchi 753-8512, Japan