Wakamatsu, Takeshi; Nakamura, Hideo; Nishimiki, Yuji; Yoshida, Kaoru; Noda, Tomoko; Taniguchi, Masato Tetrahedron Letters, 1986, vol. 27, # 50 p. 6071 - 6074 doi: 10.1016/S0040-4039(00)85401-5