AN IMPROVED PROCESS FOR THE PREPARATION OF AMORPHOUS ATORVASTATIN CALCIUM SALT (2:1)

摘要

Improved process for the preparation of amorphous atorvastatin calcium salt (2:1) comprises hydrolyzing the lactone form of atorvastatin of formula of Fig. 1 with aqueous alkali or alkaline earth metal base, extracting with organic solvent the reaction mixture and adding the same to an anti-solvent to precipitate the product and finally filtering the product to afford amorphous atorvastatin calcium (2:1). The process also comprises the preparation of amorphous atorvastatin calcium salt (2:1) from its crystalline form.