Yamamoto, Atsushi; Ohta, Eisuke; Kishigami, Nao; Tsukahara, Norihiro; Tomiyori, Yusuke; Sato, Hiroyasu; Matsui, Yasunori; Kano, Yusuke; Mizuno, Kazuhiko; Ikeda, Hiroshi Tetrahedron Letters, 2013 , vol. 54, # 31 p. 4049 - 4053