(3R,4S,5R,6R)-4-hydroxy-6-((3S,7S,9S,E)-9-(5-hydroxy-6-methoxy-7-methylbenzofuran-2-yl)-3,5,7-trimethyldec-4-enyl)-3,5-dimethyltetrahydro-2H-pyran-2-one 、
2,2-二甲氧基丙烷 在
camphor-10-sulfonic acid 作用下,
以85%的产率得到(R)-methyl 2-((4S,5S,6R)-6-((3S,7S,9S,E)-9-(5-hydroxy-6-methoxy-7-methylbenzofuran-2-yl)-3,5,7-trimethyldec-4-enyl)-2,2,5-trimethyl-1,3-dioxan-4-yl)propanoate