Miyashita, Masaaki; Sato, Hideaki; Yoshikoshi, Akira; Toki, Takashi; Matshushita, Masayuki; Irie, Hiroshi; Yanami, Tetsuji; Kikuchi, Yasuo; Takasaki, Chikahisa; Nakajima, Terumi Tetrahedron Letters, 1992 , vol. 33, # 20 p. 2833 - 2836