Suhara, Yoshitomo; Nihei, Ken-Ichi; Tanigawa, Hirokazu; Fujishima, Toshie; Konno, Katsuhiro; Nakagawa, Kimie; Okano, Toshio; Takayama, Hiroaki Bioorganic and Medicinal Chemistry Letters, 2000, vol. 10, # 10 p. 1129 - 1132 doi: 10.1016/S0960-894X(00)00189-X