Yang, Zhixiang; Kitano, Yoshikazu; Chiba, Kazuhiro; Shibata, Naohiro; Kurokawa, Hiroshi; Doi, Yohei; Arakawa, Yoshichika; Tada, Masahiro Bioorganic and Medicinal Chemistry, 2001, vol. 9, # 2 p. 347 - 356 doi: 10.1016/S0968-0896(00)00253-4