(3R,4S,5R,6R)-3,4,5-Tris-benzyloxy-6-((2S,3R,4S,5R,6R)-3,4,5-tris-benzyloxy-6-hydroxymethyl-2-methyl-tetrahydro-pyran-2-yloxymethyl)-tetrahydro-pyran-2-one   、                                                                                      (2S,3R,4S,5R,6R)-3,4,5-Tris-benzyloxy-6-(4-methoxy-benzyloxymethyl)-2-methyl-2-((2R,3R,4S,5R)-3,4,5-tris-benzyloxy-6-methylene-tetrahydro-pyran-2-ylmethoxy)-tetrahydro-pyran                                                                                                                                                              在
                                                                                                                                                                                 
三氟甲磺酸   、                                                                                                  4 A molecular sieve                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                                                        生成