| abstract |
The invention relates to an intermediate of ulipristal acetate and a preparation method thereof. Specifically, the present invention discloses various methods for preparing 3,3,20,20-bis(ethylenedioxy)-17α-hydroxy-19-norpregna-5(10),9(11)- The intermediate of diene (ie compound of formula VII) and its preparation method, the structure of said intermediate is shown in formula I, formula II, formula III, formula IV or formula V herein. The present invention also discloses a method for preparing the compound of formula VII using the above-mentioned intermediate. The method has easy-to-obtain raw materials, mild reaction conditions, high yield, low cost, few by-products in the reaction process, high purity of the target product, and is suitable for industrial production. |