PREPARATION OF (11.BETA.,16.BETA.)-21-(3-CARBOXY-3-OXOPROPOXY)-11-HYDROXY-2'-METHYL-5'H-PREGNA-1,4-DIENO17,16-DOXAZOLE-3,20-DIONE

摘要

A process for preparing the compound (11beta,16beta)-21-(3-CARBOXY-1-OXOPROPOXY)-11-HYDROXY-2'-METHYL-5'H-PREGNA-1,4-DIENO(17,16-D) OXAZOLE-3,20-DIONE which comprises reacting the compound (11beta,16beta)-11,21-DIHYDROXY-2'-METHYL-5'H-PREGNA-1, 4-DIENO(17,16-D)OXAZOLE-3,20-DIONE with succinic anhydride in a (C1-C4) alkyl ester of a (C1-C4) carboxylic acid as solvent, in the presence of a basic catalyst.