RACEMIC TAMSULOSIN FREE BASE AND METHODS OF MAKING THE SAME

摘要

Racemic tamsulosin free base is obtained in solid form. The solid form can b e formed by precipitating racemic tamsulosin free base from a solvent that comprises at least one of water or a lower alcohol. The crystalline free bas e exhibits polymorphism and two unique forms are identified. Novel intermediat es are disclosed useful in the production of tamsulosin free base: a sulfonic acid salt of 2-(o-ethoxyphenoxy)ethylamine and (3-aminosulfonyl-4- methoxy)phenylacetone.