Patent ID: 8334388
Filing Date: 2012-12-18
Classification: C07D

Abstract:
1. A method of purifying a palonosetron hydrobromide salt comprising: (a) dissolving or partially dissolving an impure (3S),(3aS) palonosetron hydrobromide salt in at least one organic solvent; (b) optionally heating the solution or partial solution of step (a) to a temperature greater than 30° C.; and (c) cooling the solution or partial solution of step (a) or step (b) to a temperature below 20° C. for a time sufficient to permit crystallization of the pure salt of (3S),(3aS) palonosetron, wherein the impure salt of (3S),(3aS) isomer has a purity of up to 99.1% and an isomer ratio of (3S),(3aS) isomer:(3S),(3aR) isomer of up to 97:3, and the pure salt of palonosetron has a purity of at least 99.5% and an isomer ratio of 99:1 or greater.