A method for the production of (11beta, 16beta) - 21 - (3 - carboxyl - 3 - oxopropoxy) - 11 - hydroxy - 2 '- methyl - 5' h - pregna - 1,4 - anhydride 17,16 - d oxazoles - - 3,20 of dihydroxydiones

摘要

A process for preparing the compound (11 beta ,16 beta )-21-(acetyloxy)-11-hydroxy-2'-methyl-5'H-pregna-1,4-dieno[17,16-d]oxazole-3,20-dione (INN deflazacort) which comprises reacting (11 beta ,16 beta )-11,21 -dihydroxy-2'-methyl-5'H-pregna-1,4-dieno[17,16-d]oxazole-3,20-dione with acetic anhydride in a suitable organic solvent in the presence of a basic catalyst and water.