Process for cephalexin hydrochloride alcoholates

摘要

The crystalline ethanol or methanol solvates of cephalexin hydrochloride are isolated in high yield from solutions of cephalexin hydrochloride in substantially anhydrous ethanol or methanol, respectively, by adding miscible C5-C6 alkanes after initiating solvate crystallization. Ethanol or methanol solutions of cephalexin hydrochloride can be prepared by adding gaseous HCl to the respective alcohol slurries of cephalexin monohydrate or the novel crystalline ethanolate or desolvated ethanolate. Alternatively, the cephalexin bis-DMF solvate-derived cephalexin hydrochloride isopropanolate can be used to prepare the crystalline hydrochloride monohydrate in accordance with the disclosed improved method.