PROCESS FOR THE PREPARATION OF DROSPIRENONE AS A FINE POWDER THROUGH A DOUBLE CHANGE OF CRYSTALLINE FORM
The present invention refers to a process for the industrial-scale preparation of 17β-hydroxy- 6β,7β;15β,16β-dimethylene-3-oxo-17α-pregn-4-ene-21-carboxylic acid y-lactone, known by the common name of Drospirenone, in the form of a fine powder without the use of mechanical grinding or micronization techniques, but rather exploiting a double change of crystalline form, from Crystalline Form I to Crystalline Form II and from Crystalline Form II to Crystalline Form I. The invention also refers to the new Crystalline Form II of Drospirenone obtained in the process.