Esters and ethers of 16-methyl-9.alpha.-halocorticosteroids
Pregnadienediones I [R = Cl, F; R1 = H, EtCO, F3CCO, (tetrahydropyran-2-yl)oxy; R2 = H, EtCO, BuCO; R3 = H, OAc, O2CEt] (16 compds.) were prepd. Thus, 20 g I (R = Cl, R1-R3 = H), was treated with (F3CCO)2O in pyridine to give 24.1 g I (R = Cl, R1 = F3CCO, R2 = R3 = H) (II). Heating 20 g II with BuCO2H-(F3CCO2)2O at 80.degree. gave 18.1 g I (R = Cl, R1 = F3CCO, R2 = BuCO, R3 = H), which (7.9 g) was partially deacylated and then esterified using EtCO2H - (F3CCO)2O to give 22.2 g I (R = Cl, R1 = EtCO, R2 = BuCO, R3 = H). I (R = Cl, R1 = EtCO, R2 = R3 = H) had 4.48 times the antiinflammatory activity of fluocinolone acetonide in the McKenzie assay.