Hydrogenation (H-2/PdC) of estrone (1) gives estrane-3,17-dione (2), t
he 5 alpha,10 alpha A/B ring fusion stereochemistry being established
by NMR. Reduction of estrone using D-2/PdC gives 1 alpha,2 alpha,4 alp
ha,5 alpha 6,6,9 alpha 10 alpha-d(8)-estrane-3,17-dione (3).