(11β)-11-Hydroxy-17,20:20,21-bis[methylenebis(oxy)]-pregna-1,4-dien-3-one-d8 is an intermediate in synthesizing Prednisolone-d8 Acetate (P703752), a labelled Prednisolone Acetate (P703750). Synthetic corticosteroid; metabolically interconvertible with Prednisone (P703780).