1. Department of Medicinal Chemistry School of Pharmacy Tokyo University of Pharmacy and Life Sciences 1432-1 Horinouchi Hachioji Tokyo 192-0392 Japan
2. Graduate School of Life and Environmental Sciences University of Tsukuba 1-1-1 Tennodai Tsukuba Ibaraki 305-8572 Japan
3. Present address: Department of Chemical Science and Engineering School of Materials and Chemical Technology Tokyo Institute of Technology Tokyo 152-8552 Japan
4. Department of Biotechnology Graduate School of Agricultural and Life Sciences The University of Tokyo 1-1-1 Yayoi, Bunkyo-ku Tokyo 113-8657 Japan
5. Collaborative Research Institute for Innovative Microbiology The University of Tokyo Bunkyo-ku Tokyo 113-8657 Japan