溴甲苯   、                                                                                      (2R,3S,4S,5R,6R)-4-Allyloxy-2-allyloxymethyl-6-(2,2,2-trichloro-ethoxy)-tetrahydro-pyran-3,5-diol                                                                                                                                                              在
                                                                                                                                                                                 sodium hydride                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
N,N-二甲基甲酰胺                                                                                  为溶剂,
                                                                                                                                                                                        生成                                                 (2R,3S,4S,5R,6S)-4-Allyloxy-2-allyloxymethyl-3,5-bis-benzyloxy-6-(2,2-dichloro-vinyloxy)-tetrahydro-pyran   、                                                                                             
(2R,3S,4S,5R,6R)-4-Allyloxy-2-allyloxymethyl-3,5-bis-benzyloxy-6-(2,2,2-trichloro-ethoxy)-tetrahydro-pyran