Novel Process for Preparation of Indacaterol or Its Pharmaceutically Acceptable Salts

摘要

A novel process the for preparation of Indacaterol or its pharmaceutically acceptable salts and novel intermediates employed in the preparation thereof that is economically significant for large scale.

主权项

1) A process for preparation of Indacaterol free base or its pharmaceutically acceptable salt comprising the steps of:
i) treating the compound of formula II with the reducing agent to obtain compound of formula III where L is good leaving group; ii) treating compound of formula III with silylated protecting reagent to obtain compound of formula IV where A is silylated protective group; iii) reacting the compound of formula IV with compound of formula V or its derivatives in the presence of a base to obtain compound of formula VI, iv) desilylating compound of formula VI to obtain compound of formula VII v) debenzylating the compound of formula VII to obtain compound of formula I Indacaterol free base vi) optionally converting the compound of formula Ito its acid addition salt, preferably pharmaceutical acceptable salts.