(2S,3R)-N-Cbz-2,3-bisbenzyloxy-4-amino-butyric acid 、 benzyl (4aR,6R,7R,8S,8aS)-6-[(1R,2R,3S,4R,6S)-2-[(2S,3R,4S,5R)-4-[[(4aS,6R,7R,8R,8aS)-8-hydroxy-2-phenyl-3-phenylmethoxycarbonyl-7-(phenylmethoxycarbonylamino)-4,4a,6,7,8,8a-hexahydro-2H-pyrano[2,3-e][1,3]oxazin-6-yl]oxy]-3-hydroxy-5-(hydroxymethyl)oxolan-2-yl]oxy-4-amino-3-hydroxy-6-(phenylmethoxycarbonylamino)cyclohexyl]oxy-8-hydroxy-2-phenyl-7-(phenylmethoxycarbonylamino)-4,4a,6,7,8,8a-hexahydro-2H-pyrano[2,3-e][1,3]oxazine-3-carboxylate 在
benzotriazol-1-yloxyl-tris-(pyrrolidino)-phosphonium hexafluorophosphate 、
N,N-二异丙基乙胺 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以82.5%的产率得到