rubellin A   、                                                                                      
碘甲烷                                                                                                                                                              在
                                                                                                                                                                                 
silver(l) oxide                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
丙酮                                                                                  为溶剂,
                                                                                                                                                    反应 48.0h,
                                                                                                                以90 mg的产率得到(1S,17R,20R,21S,30S)-5,20,30-trihydroxy-9,25-dimethoxy-27-methyl-22-oxaheptacyclo[15.13.0.01,21.03,16.06,15.08,13.024,29]triaconta-3,5,8(13),9,11,15,18,24(29),25,27-decaene-7,14,23-trione