3-methyl-3',4'-di-O-(S)-camphanoyl-(3'R,4'R)-(+)-cis-khellactone 在
N-溴代丁二酰亚胺(NBS) 作用下,
以
苯 为溶剂,
反应 6.0h,
以77%的产率得到[(9R,10R)-3-(bromomethyl)-8,8-dimethyl-2-oxo-9-[(1S,4R)-4,7,7-trimethyl-3-oxo-2-oxabicyclo[2.2.1]heptane-1-carbonyl]oxy-9,10-dihydropyrano[2,3-f]chromen-10-yl] (1S,4R)-4,7,7-trimethyl-3-oxo-2-oxabicyclo[2.2.1]heptane-1-carboxylate