抄録
The partial synthesis of (20R)-17α, 20, 21-trihydroxypregna-1, 4-dien-3-one (its Dring moiety is identical with that of cortisone) from androsta-1, 4-diene-3, 17-dione is described. This conforms a model experiment for the synthesis of adrenal steroid compounds from the latter compound without affecting its A-ring moiety.