摘要 |
<p>Pure Form 1 ranitidine hydrochloride is prepared by a process of crystallization from a solution of ranitidine hydrochloride in a mixed solvent comprising 1 part by volume of at least one lower alkanol such as ethanol and 1 - 2.0 parts by volume of a C6 - C10 aromatic hydrocarbon such as toluene, and in the presence of seed crystals of pure Form 1 ranitidine hydrochloride. In the preferred process according to the invention, the ranitidine hydrochloride is prepared in situ in the solvent mixture by adding hydrochloric acid to a solution of the free base in the solvent mixture, in the presence of the seed crystals.</p> |