(2S,3S,4R,5R,6R)-1-(benzyloxy)-6-((1S,3S,4R,5S)-1,4-dimethyl-2,8-dioxabicyclo[3.2.1]-octan-3-yl)-2,4-dimethylheptane-3,5-diol 、
2,2-二甲氧基丙烷 在
4-甲基苯磺酸吡啶 作用下,
以94%的产率得到(1S,3R,4R,5S)-3-((R)-1-{(4R,5R,6S)-6-[(S)-1-(benzyloxy)propano-2-yl]-2,2,5-trimethyl-1,3-dioxan-4-yl}ethyl)-1,4-dimethyl-2,8-dioxabicyclo[3.2.1]octane