(+/-)-7,7-ethanediyldioxy-4
t-hydroxy-4b-methyl-1-oxo-(4a
r,4b
t,10a
t)-1,2,3,4,4a,4b,5,6,7,8,10,10a-dodecahydro-phenanthrene-2-carbaldehyde 在
1,4-二氧六环 、
丁烯酮 、
三乙胺 作用下,
生成
rac-3,3-ethanediyldioxy-11β-hydroxy-14,16-dioxo-14,15-seco-D-homo-13α-androst-5-en-18-al