1. Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan, Department of Chemistry, Faculty of Science, El-Menoufia University, Shebin El-Kom, El-Menoufia, Egypt, and Chemical Institute, Aarhus University, DK-8000 Aarhus C, Denmark