Process for preparation of esomeprazole sodium of high chemical purity and new forms of esomeprazole sodium

Abstract

A process for preparing esomeprazole sodium comprises the steps of providing a solution of esomeprazole sodium in a solvent constituted mainly of methanol or only of methanol; and carrying out precipitation or crystallization of esomeprazole sodium from said solution. Esomeprazole sodium is preferably obtained from pure form of neutral racemate through chiral chromatography using methanol-based mobile phase, and a subsequent reaction with sodium source. Novel crystal and semicrystal forms of esomeprazole sodium can be provided repeatedly and in physically stable and highly pure form.