1,2:3,4-di-O-isopropylidene-6-O-α-L-rhamnopyranosyl-α-D-galactopyranose 在
奎宁环 、
2-羧基苯硼酸 、 10-(3,5-dimethoxyphenyl)-9-mesityl-1,3,6,8-tetramethoxyacridin-10-ium tetrafluoroborate 作用下,
以
乙腈 为溶剂,
以51%的产率得到(2S,3S,5R,6R)-3,5-dihydroxy-2-methyl-6-(((3aR,5R,5aS,8aS,8bR)-2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4',5'-d]pyran-5-yl)methoxy)tetrahydro-4H-pyran-4-one