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Pregnadienediones I (R = Cl, F; R1 = H, COCF3, COEt, Ac; R2 = H, OH, OAc; R3 = H, COBu) (18 compds.) were prepd. Thus, acylation of I (R = Cl, R1-R3 = H) using (F3CCO)2O followed by BuCO2H gave I (R = Cl, R1 = COCF3, R2 = H, R3 = COBu) (II). Iodination of II and subsequent acetolysis gave I (R = Cl, R1 = COCF3, R2 = OAc, R3 = COBu) which was partially deacylated to I (R = Cl, R1 = H, R2 = OAc, R3 = COBu) (III). The antiinflammatory activity of III was 4.5 times that of fluocinolone acetonide.