Patent ID: 8362042
Filing Date: 2013-01-29
Classification: A61P,C07D

Abstract:
1. A process for preparing stable R-(+)-lansoprazole butylamine salt comprising the following steps: (a) treating racemic lansoprazole with R-(+)-2,2′-dihydroxy-1,1′-binaphthyl (“R-(+)-BINOL”) in a suitable solvent to form the inclusion complex of R-(+)-lansoprazole with R-(+)-BINOL; (b) removing the inclusion complex of R-(+)-lansoprazole with R-(+)-BINOL prepared in step (a) from the solvent and adding a mixture of organic solvents; (c) crystallizing the R-(+)-lansoprazole-R-(+)-BINOL inclusion complex from the mixture of organic solvents; (d) enriching the R-(+)-lansoprazole-R-(+)-BINOL inclusion complex to obtain a purity of more than about 97% e.e.; (e) cleaving the enriched R-(+)-lansoprazole-R-(+)-BINOL inclusion complex; (f) separating the R-(+)-BINOL and R-(+)-lansoprazole; (g) isolating the R-(+)-lansoprazole; and (h) reacting the R-(+)-lansoprazole with a butylamine to form a stable R-(+)-lansoprazole butylamine salt.