NOVEL CRYSTALLINE FORMS OF ENTACAPONE AND PRODUCTION THEREOF

摘要

The invention relates to three novel forms of entacapone. These are peripheral and selective COMT inhibitors which in combination with levodopa and decarboxylase inhibitors can be used to treating Parkinson's syndrome. Said novel forms arise by crystallization of entacapone in respectively determined conditions. In certain cases, entacapone can be used as a raw product, in a special case it can be used in situ as the product of Knoevenagel condensation of 3,4-dihydroxy-5-nitro-benzaldehyde and N,N-diethyl-2-cyano-acetamide. Also disclosed are improvements of said condensation in relation to the catalyst and the production of the two components thereof.