Sano, Shigeki; Miwa, Toshio; Hayashi, Kazuhiko; Nozaki, Kazuo; Ozaki, Yohei; Nagao, Yoshimitsu Tetrahedron Letters, 2001, vol. 42, # 24 p. 4029 - 4031 doi: 10.1016/S0040-4039(01)00649-9