Suzuki, Takeshi; Imanishi, Naoki; Itahana, Hirotsune; Watanuki, Susumu; Miyata, Keiji; Ohta, Mitsuaki; Nakahara, Hideaki; Yamagiwa, Yoko; Mase, Toshiyasu Chemical and Pharmaceutical Bulletin, 1998 , vol. 46, # 7 p. 1116 - 1124