1-benzyloxy-3-metylene-2-azetidinone   、                                                                                      (Z)-2-(benzhydryloxy)-N-benzyl-2-oxoethan-1-imine oxide                                                                                                                                                                                                                                                                                                          生成                                                 diphenylmethyl (4S*,7R*)-6-benzyl-2-benzyloxy-1-oxo-5-oxa-2,6-diazaspiro <3,4>-octane-7-carboxylate   、                                                                                             
diphenylmethyl (4S*,7S*)-6-benzyl-2-benzyloxy-1-oxo-5-oxa-2,6-diazaspiro<3,4>octane-7-carboxylate