1. Research Laboratory of Hydrothermal Chemistry, Faculty of Science, Kochi University, Akebono-cho, Kochi 780-8520, Japan, Rigaku Corporation, Matsubara-cho, Akishima, Tokyo 196-8666, Japan, and Laboratory of Natural Products Synthesis, Faculty of Science, Kochi University, Akebono-cho, Kochi 780-8520, Japan