SOLID AND CRYSTALLINE DUTASTERIDE AND PROCESSES FOR PREPARATION THEREOF

摘要

The present invention relates to a synthetic process for manufacturing Dutasteride comprising the mixed anhydride formation, subsequent reaction with 2,5- bis(trifluoromethyl)phenylamine in the presence of an appropriate Lewis catalyst and its isolation, purification and crystallization from acetonitrile/water. The invention also relates to a novel polymorphic form of Dutasteride, called form III, and a pharmaceutical composition comprising it.