Usami, Yoshihide; Watanabe, Ryo; Fujino, Yuiko; Shibano, Makio; Ishida, Chihiro; Yoneyama, Hiroki; Harusawa, Shinya; Ichikawa, Hayato Chemical and Pharmaceutical Bulletin, 2012 , vol. 60, # 12 p. 1550 - 1560