The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 06, 2010
Filed:
Oct. 08, 2004
Isao Wada, Tokushima, JP;
Yutaka Kameyama, Tokushima, JP;
Isao Wada, Tokushima, JP;
Yutaka Kameyama, Tokushima, JP;
Otsuka Chemical Co., Ltd., Osaka-shi, unknown;
Taiho Pharmaceutical Co., Ltd., Tokyo, JP;
Abstract
The present invention provides 2β-chloromethyl-2α-methylpenam-3α-carboxylic acid benzhydryl ester (CMPB) crystals of excellent stability, and a process for producing the CMPB crystals comprising the steps of (A) concentrating a solution containing CMPB; (b) subjecting the thus-obtained concentrate to column chromatography; (C) concentrating a CMPB-containing fraction; and (D) dissolving the thus-obtained CMPB-containing concentrate in an ether solvent and adding a hydrocarbon solvent to the resulting solution to precipitate CMPB crystals.