Taniguchi, Yuki; Nagata, Kensuke; Kitamura, Tsugio; Fujiwara, Yuzo; Deguchi, Daisuke; Maruo, Masafumi; Makioka, Yoshikazu; Takaki, Ken Tetrahedron Letters, 1996 , vol. 37, # 20 p. 3465 - 3466