Nagumo, Yoko; Oguri, Hiroki; Shindo, Yumi; Sasaki, Shin-ya; Oishi, Tohru; Hirama, Masahiro; Tomioka, Yoshihisa; Mizugaki, Michinao; Tsumuraya, Takeshi Bioorganic and Medicinal Chemistry Letters, 2001, vol. 11, # 15 p. 2037 - 2040 doi: 10.1016/S0960-894X(01)00358-4