(2S,6S)-ethyl 2-ethyl-1,2,3,6-tetrahydro-4-hydroxy-5-methyl-3-oxo-6-phenylpyridine-2-carboxylate 、
(1S)-(-)-莰烷酰氯 在
4-二甲氨基吡啶 作用下,
以
二氯甲烷 为溶剂,
以92%的产率得到(2S,6S,4(1S))-ethyl 2-ethyl-1,2,3,6-tetrahydro-4-(4,7,7-trimethyl-3-oxo-2-oxabicyclo[2.2.1]heptane-1-carbonyl)oxy-5-methyl-3-oxo-6-phenylpyridine-2-carboxylate