Takeda, Yasuyuki; Uoto, Kouichi; Chiba, Jun; Horiuchi, Takao; Iwahana, Michio; Atsumi, Ryo; Ono, Chiho; Terasawa, Hirofumi; Soga, Tsunehiko Bioorganic and Medicinal Chemistry, 2003 , vol. 11, # 20 p. 4431 - 4447