methyl (2S,3S,3'aS,4S,5'R)-3',3'a,4,5,5',6'-hexahydro-8'-hydroxy-4-[2-hydroxyethyl]-3-methyl-5'-pentyl-spiro[furan-2(3H),2'-[2H]pyrano[2,3,4-de][1]benzopyran]-9'-carboxylate 、
叔丁基二甲硅基三氟甲磺酸酯 在
2,6-二甲基吡啶 作用下,
以
二氯甲烷 为溶剂,
以83%的产率得到methyl (2S,3S,3'aS,4S,5'R)-8'-[(1,1-dimethylethyl)dimethylsilyl]oxy-4-[2-[[(1,1-dimethylethyl)dimethylsilyl]oxy]ethyl]-3',3'a,4,5,5',6'-hexahydro-3-methyl-5'-pentyl-spiro[furan-2(3H),2'-[2H]pyrano[2,3,4-de][1]benzopyran]-9'-carboxylate