Kawai, Hiroyuki; Hayakawa, Yoichi; Nakagawa, Mayasa; Furihata, Kazuo; Seto, Haruo; Otake, Noboru Tetrahedron Letters, 1984, vol. 25, # 18 p. 1937 - 1940 doi: 10.1016/S0040-4039(01)90080-2