(2R,3S,4S,5R,6S,7R,9S,10S,11R,12S,13R,15R,17R)-2,4,6,10,12-Pentamethyl-19-trityloxy-nonadecane-1,3,5,7,9,11,13,15,17-nonaol   、                                                                                      
2,2-二甲氧基丙烷                                                                                                                                                              在
                                                                                                                                                                                 
对甲苯磺酸                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
N,N-二甲基甲酰胺                                                                                  为溶剂,
                                                                                                                                                                                        以0.7 mg的产率得到(2R,3R,4R)-2-[(4R,6S)-6-((S)-1-{(4R,5S,6R)-6-[(4R,6R)-2,2-Dimethyl-6-(2-trityloxy-ethyl)-[1,3]dioxan-4-ylmethyl]-2,2,5-trimethyl-[1,3]dioxan-4-yl}-ethyl)-2,2-dimethyl-[1,3]dioxan-4-yl]-4-((4S,5R)-2,2,5-trimethyl-[1,3]dioxan-4-yl)-pentan-3-ol