Patent ID: 6482931
Filing Date: 2002-11-19
Classification: C07H

Abstract:
Process for the preparation of 9-deoxo-8a-aza-8a-homoerythromycin A of formula V via the stereospecific Beckmann rearrangement, in a reaction mixture using pyridine as main solvent, of a compound of formula II into two imidate intermediates III and IV and then the reduction of said compounds III and IV, characterized in that said compounds III and IV formed in the reaction mixture of the Beckmann rearrangement are not isolated from said mixture and are employed directly in the reduction stage using a sufficient amount of a borohydride, after extraction of the pyridine with a hydrocarbon which is miscible with the latter and in which said imidates III and IV, in the salt form, are insoluble.