(1S,4aS,5S,8aS)-5-{(R)-1-Acetoxy-2-[(1R,2S)-2-(tert-butyl-diphenyl-silanyloxymethyl)-1-methyl-5-oxo-cyclopentyl]-ethyl}-1-(tert-butyl-diphenyl-silanyloxy)-4,7-dioxo-octahydro-naphthalene-4a-carboxylic acid methyl ester 在
potassium bis(tetramethylsilyl)amide 作用下,
以
四氢呋喃 为溶剂,
反应 1.5h,
以71%的产率得到methyl (4S,5S,8R,9S,10R,11R,13R,14S,17S)-11-acetyloxy-4-[tert-butyl(diphenyl)silyl]oxy-17-[[tert-butyl(diphenyl)silyl]oxymethyl]-14-hydroxy-13-methyl-1,7-dioxo-2,3,4,5,6,8,9,11,12,15,16,17-dodecahydrocyclopenta[a]phenanthrene-10-carboxylate