Nokami, Junzo; Mandai, Tadakatsu; Nishimura, Akira; Takeda, Takashi; Wakabayashi, Shoji; et al. Tetrahedron Letters, 1986, vol. 27, # 42 p. 5109 - 5112 doi: 10.1016/S0040-4039(00)85146-1