| 摘要 |
The invention relates to the preparation of a compound of the formula <CHEM> or a stereoisomeric compound thereof, in which formula the the l,2-position is saturated or is a double bond; X1 is selected from hydrogen, fluorine, chlorine and bromine X2 is selected from hydrogen, fluorine, chlorine and bromine R2 is selected from straight and branched hydrocarbon chains having l-l0 carbon atoms and R7 is hydrogen or an acyl group with l-l0 carbon atoms arranged in a straight or branched chain, characterized by reaction of a steroid compound of the formula <CHEM> with an aldehyde compound of the formula <CHEM> wherein X1, X2, R2, R7 and <IMAGE> have the meanings given above, in the presence of an acid catalyst. The products of the process are useful intermediates in the preparation of novel glucocorticosteroids which possess high anti-inflammatory potency at the place of application and low glucocorticord systemic potency. |
