1. Contribution from the Department of Chemistry, Faculty of Science, Saitama University, Shimo-Ohkubo, Sakura-ku, Saitama 338-8570, Japan; Department of Chemistry, Nara University of Education, Takabatake-cho, Nara 630-8528, Japan; and Institute for Natural Science, Nara University, Misasagi-cho, Nara 631-8502, Japan