(2E,5S,9R,11Z,13R,14S)-10-hydroxy-20-methoxy-18-(methoxymethoxy)-7,7,13,14-tetramethyl-6,8,15-trioxatricyclo[15.4.0.05,9]henicosa-1(17),2,11,18,20-pentaen-16-one 以100%的产率得到(2E,5S,9S,11Z,13R,14S)-20-methoxy-18-(methoxymethoxy)-7,7,13,14-tetramethyl-6,8,15-trioxatricyclo[15.4.0.05,9]henicosa-1(17),2,11,18,20-pentaene-10,16-dione