乙酸酐 、
[(3'R,3aR,4'S,5R,5'R,6S,6'R,6aR)-5-[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]-4',5'-dihydroxy-6'-methoxy-2,2-dimethylspiro[5,6a-dihydro-3aH-furo[2,3-d][1,3]dioxole-6,2'-oxane]-3'-yl] acetate 在
4-二甲氨基吡啶 、
三乙胺 作用下,
以
二氯甲烷 为溶剂,
以77%的产率得到5-(2,2-dimethyl-(4R)-1,3-dioxolan-4-yl)-6'-methoxy-2,2-dimethyl-3',4'-di(methylcarbonyl-oxy)-(3'R,3aR,4'R,5R,5'R,6S,6'R,6aR)-spiro[perhydrofuro[2,3-d][1,3]-dioxole-6,2'-(3'H,4'H,5'H,6'H-pyran)]-5-yl acetate