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:
Jul. 31, 2012
Filed:
Jun. 13, 2007
Keita Nishino, Takasago, JP;
Teruyoshi Koga, Takasago, JP;
Masafumi Fukae, Takasago, JP;
Yasuyoshi Ueda, Takasago, JP;
Keita Nishino, Takasago, JP;
Teruyoshi Koga, Takasago, JP;
Masafumi Fukae, Takasago, JP;
Yasuyoshi Ueda, Takasago, JP;
Kaneka Corporation, Osaka, JP;
Abstract
The present invention relates to a method for crystallization of (2R)-2-{(3S,4S)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-2-oxoazetidin-4-yl}propionic acid, and is characterized in that crystallization is carried out by mixing a solution containing the compound with a substituted aromatic hydrocarbon solvent and/or a halogenated hydrocarbon solvent. The method can provide a crystal of the compound with a high purity and a high yield while the content of 2S isomer is kept at a low level.