4-O,5-O-ditert-butyl 3-O-methyl (1S,3S,4S,5R,6R,7R)-7-acetyloxy-6-[(E,4S,6S)-4,6-dimethyloct-2-enoyl]oxy-4-hydroxy-1-[(4S,5R)-4-hydroxy-5-methyl-3-methylidene-6-phenylhexyl]-2,8-dioxabicyclo[3.2.1]octane-3,4,5-tricarboxylate                                                                                                                                                              在
                                                                                                                                                                                 
2,4,6-三甲基吡啶   、                                                                                                  
trifluoromethanesulfonic acid anhydride                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                    反应 2.0h,
                                                                                                                以26%的产率得到4-O,5-O-ditert-butyl 3-O-methyl (1S,3S,4S,5R,6R,7R)-7-acetyloxy-6-[(E,4S,6S)-4,6-dimethyloct-2-enoyl]oxy-4-hydroxy-1-[2-[(8R)-8-methyl-8,9-dihydro-5H-benzo[7]annulen-6-yl]ethyl]-2,8-dioxabicyclo[3.2.1]octane-3,4,5-tricarboxylate