Ishibashi, Hiroyuki; Tabata, Takashi; Hanaoka, Kyoko; Iriyama, Hiroko; Akamatsu, Susumu; Ikeda, Masazumi Tetrahedron Letters, 1993, vol. 34, # 3 p. 489 - 492 doi: 10.1016/0040-4039(93)85109-A