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:
Mar. 16, 2010
Filed:
Dec. 03, 2004
Applicants:
Nanping Zhong, Shijiazhuang, CN;
Xianfeng Zhao, Shijiazhuang, CN;
Hui MA, Shijiazhuang, CN;
Yujie Chen, Shijiazhuang, CN;
Inventors:
Nanping Zhong, Shijiazhuang, CN;
Xianfeng Zhao, Shijiazhuang, CN;
Hui Ma, Shijiazhuang, CN;
Yujie Chen, Shijiazhuang, CN;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D 211/86 (2006.01);
U.S. Cl.
CPC ...
Abstract
The present invention relates to the preparation of the (S)-(−)-amlodipine and (R)-(+)-amlodipine by means of enantiomeric separation of racemic amlodipine mixture, in which, L- or D-tartaric acid is used as resolution agent, and organic solvent containing 2-butanone is used as solvent. The 2-butanone used in the present invention has the advantage of low boiling point, low toxicity, litter pollution, and the method is suitable for large-scaled production.