Kiho, Toshihiro; Nakayama, Mizuka; Yasuda, Kayo; Miyakoshi, Shunichi; Inukai, Masatoshi; Kogen, Hiroshi Bioorganic and Medicinal Chemistry Letters, 2003, vol. 13, # 14 p. 2315 - 2318 doi: 10.1016/S0960-894X(03)00432-3