1. Drug Discovery Research Center,
Taiho Pharmaceutical Co. Ltd., Okubo 3, Tsukuba, Ibaraki 300-2611,
Japan
2. Laboratory of Pharmaceutical
and
Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi,
Gifu 501-1196, Japan
3. Faculty of Pharmaceutical
Sciences,
Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812,
Japan