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:
Oct. 28, 2008
Filed:
Jul. 12, 2006
Applicants:
Tianchun Liu, Hangzhou, CN;
Youming Huang, Hangzhou, CN;
Weirong Fan, Hangzhou, CN;
Inventors:
Assignee:
Zhejiang Chiral Medicine Chemicals Co., Ltd., Hangzhou, CN;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 229/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
This invention relates to an improved process for the preparation of substantially pure, stable anhydrous gabapentin. Thus, cyclohexane 1,1-diacetic acid monoamide is first treated with NaOH/NaClO to form 3,3-pentamethylenebutyrolactam, which is treated with aqueous HCl solution under reflux to provide gabapentin HCl salt, which is then neutralized with NaOH followed by a dehydration step to provide substantially pure, storage-stable, pharmaceutical grade gabapentin.