| 摘要 |
<p>9alpha-Fluoro 11beta-hydroxy steroids of formula (I), in which R1 is hydroxy or 1-5C acyloxy, and R2 is H or alpha-hydroxy, are made by treating a steroid of formula (II) with anhydrous hydrofluoric acid, in presence of a Lewis base. The Lewis base can be an aliphatic or cyclic ether, tetrahydrofurane, an amide, alkyl formamide, dimethyl formamide or a deriv. of carbonic or thiocarbonic acid.</p> |
