Ohta, Shunsaku; Hayakawa, Satoshi; Tamai, Yoshimi; Yuasa, Teruyuki; Okamoto, Masao
Heterocycles, 1987 , vol. 26, # 1 p. 141 - 146

Hayakawa, Satoshi; Baba, Junko; Okamoto, Masao; Ohta, Shunsaku
Chemical and Pharmaceutical Bulletin, 1988 , vol. 36, # 1 p. 22 - 32