Takeda, Yohko; Nishiyama, Hironobu; Minoru, Ishikura; Kamata, Kazuyuki; Terashima, Masanao
Heterocycles, 1992 , vol. 33, # 1 p. 173 - 177

Nagasaki, Izuru; Suzuki, Yumiko; Iwamoto, Ken-Ichi; Higashino, Takeo; Miyashita, Akira
Heterocycles, 1997 , vol. 46, # 1 p. 443 - 450