methyl (1R,14R,15R,19S,20R)-5,8-diacetyloxy-1,15,19-trimethylpentacyclo[12.8.0.02,11.04,9.015,20]docosa-2,4,6,8,10-pentaene-19-carboxylate 在
sodium tetrahydroborate 、
silver(l) oxide 作用下,
以
甲醇 、
乙醚 为溶剂,
反应 19.25h,
以45%的产率得到methyl (1R,14R,15R,19S,20R)-1,15,19-trimethyl-5,8-dioxopentacyclo[12.8.0.02,11.04,9.015,20]docosa-2,4(9),6,10-tetraene-19-carboxylate