Hattori, Kouji; Tanaka, Akira; Okitsu, Osamu; Tabuchi, Seiichiro; Taniguchi, Kiyoshi; Nishio, Mie; Koyama, Satoshi; Higaki, Masahide; Seki, Jiro; Sakane, Kazuo Bioorganic and Medicinal Chemistry Letters, 2005, vol. 15, # 12 p. 3091 - 3095 doi: 10.1016/j.bmcl.2005.04.047