乙酸酐 、 4-(
rac-3,3-ethanediyldioxy-11β,18a-epoxy-18a-methyl-16,20-dioxo-18-homo-pregna-5,14,18-trien-21-oyl)-morpholine 在
吡啶 作用下,
生成
4-(rac-20-acetoxy-3,3-ethanediyldioxy-11β,18a-epoxy-18a-methyl-16-oxo-18-homo-pregna-5,14,17(20)ξ,18-tetraen-21-oyl)-morpholine