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US 6,444,796 B1Granted
Method of preparing form II crystals of clarithromycin
AssigneeHanmi Pharm. Co., Ltd.
InventorsKwee-Hyun Suh, Mi-Ra Seong, Nam-Du Kim, Gwan-Sun Lee
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Abstract
Pure Form II crystals of clarithromycin can be prepared by a simple, high-yield process comprising the steps of treating crude clarithromycin or different crystal forms of clarithromycin with formic acid in an organic solvent to obtain crystalline clarithromycin formate and neutralizing the clarithromycin formate with a base in a mixture of water and a water-miscible organic solvent.
Claims9
A method of preparing Form II crystals of clarithromycin of formula (I) comprising the steps of:
- (a) treating clarithromycin with formic acid in an organic solvent to give crystalline clarithromycin formate of formula (II) and (b) neutralizing the clarithromycin formate with a base in a mixture of water and a water-miscible organic solvent:
Dependencies are inferred from the claim text.