Hirashima, Shintaro; Oka, Takahiro; Ikegashira, Kazutaka; Noji, Satoru; Yamanaka, Hiroshi; Hara, Yoshinori; Goto, Hiroyuki; Mizojiri, Ryo; Niwa, Yasushi; Noguchi, Toru; Ando, Izuru; Ikeda, Satoru; Hashimoto, Hiromasa Bioorganic and Medicinal Chemistry Letters, 2007 , vol. 17, # 11 p. 3181 - 3186