Sawamura, Kiyoto; Yoshida, Keigo; Suzuki, Akari; Motozaki, Toru; Kozawa, Ikuko; Hayamizu, Takashi; Munakata, Ryosuke; Takao, Ken-Ichi; Tadano, Kin-Ichi Journal of Organic Chemistry, 2007, vol. 72, # 16 p. 6143 - 6148 doi: 10.1021/jo0708442