(2S,3S)-3-[(2S,5S,6S)-5-((2S,5R,6S)-5-Benzyloxy-6-methyl-tetrahydro-pyran-2-yloxy)-6-methyl-tetrahydro-pyran-2-yloxy]-hex-5-yn-2-ol                                                                                                                                                              在
                                                                                                                                                                                 
tungsten pentacarbonyl tetrahydrofuran   、                                                                                                  
三乙胺                                                                                                                                  作用下,
                                                                                                                                                                                                                            生成                                                 (2S,3S)-3-[(2S,5S,6S)-5-((2S,5R,6S)-5-Benzyloxy-6-methyl-tetrahydro-pyran-2-yloxy)-6-methyl-tetrahydro-pyran-2-yloxy]-2-methyl-3,4-dihydro-2H-pyran