1. Integrated Center for Science and Humanities, Fukushima Medical University, 10-6 Sakae-Machi, Fukushima, Fukushima 960-8516, Japan
2. Department of Organic and Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan
3. Hiroshima University, 1-2-3 Kasumi, Minami-Ku, Hiroshima, Hiroshima 734-8553, Japan