(4S,6S)-6-[(1R)-2-benzyloxy-1-methyl-ethyl]-4-[(E)-1-methyl-propenyl]-[1,3]dioxan-2-one 、 alkaline earth salt of/the/ methylsulfuric acid 以
甲苯 为溶剂,
反应 4.5h,
以34%的产率得到(4R,8S)-8-[(1R)-2-benzyloxy-1-methyl-ethyl]-4,5-dimethyl-3,4,7,8-tetrahydrooxocin-2-one