1. Department of Natural Product Chemistry, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan.
2. Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Tokyo, Japan.
3. Institute of Medical Mycology, Teikyo University, Tokyo, Japan.
4. Microbial Chemistry and Medical Research Laboratories, Graduate School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan.