[EN] METHOD FOR PREPARING 17 alpha-ACETOXY-11beta-(4-N,N-DIMETHYLAMINOPHENYL)-19-NORPREGNA-4,9-DIENE-3,20-DIONE, INTERMEDIATES THEREOF, AND METHODS FOR THE PREPARATION OF SUCH INTERMEDIATES [FR] PROCEDE DE PREPARATION DE 17 DOLLAR G(A)-ACETOXY-11 DOLLAR G(B)-(4-N,N-DIMETHYLAMINOPHENYL)-19-NORPREGNA-4,9-DIENE-3,20-DIONE, D'INTERMEDIAIRES DE CEUX-CI ET PROCEDES DE PREPARATION DESDITS INTERMEDIAIRES