[(3'aS,5R,6'R,7'R,7'aS)-7'-acetyloxy-4-ethenyl-2',2'-dimethylspiro[2H-furan-5,4'-3a,6,7,7a-tetrahydro-[1,3]dioxolo[4,5-c]pyran]-6'-yl]methyl acetate   、                                                                                      
1,4-萘醌                                                                                                                                                                                              以
                                                                                         
甲苯   、                                                                                         
氯仿                                                                                  为溶剂,
                                                                                                                                                                                        以62%的产率得到((3aR,3'R,7R,7aS)-7-acetoxy-2,2-dimethyl-6',11'-dioxo-3a,6,6',7,7a,11'-hexahydro-1'H-spiro[[1,3]dioxolo[4,5-c]pyran-4,3'-anthra[2,1-c]furan]-6-yl)methyl acetate