Title:
PROCESS FOR THE PREPARATION OF GABAPENTIN HYDROCHLORIDE
Document Type and Number:
WIPO Patent Application WO/2007/019752
Kind Code:
A1
Abstract:
The present invention provided a process for the preparation of gabapentin hydrochloride. The process comprises: conventing 1,5-dicyano-2,4-dioxo-3-azaspiro[5,5]undecane into 1,5-dicarbamoyl-2,4-dioxo-3-azaspiro[5,5]undecane at a temperature between 65 to 85 and in the presence of strong acid, then carrying out the Hoffmann rearrangement reaction in the presence of base. The starting material of present process is readily available. The process is simple, and can decrease the purification procedure for the intermediate, reduce the cost, and obtain the product with high purity.
Inventors:
PENG ZHENYUN (CN)
ZHU WEI (CN)
ZHU WEI (CN)
Application Number:
PCT/CN2006/000830
Publication Date:
February 22, 2007
Filing Date:
April 28, 2006
Export Citation:
Assignee:
NHWA PHARMA CORP (CN)
PENG ZHENYUN (CN)
ZHU WEI (CN)
PENG ZHENYUN (CN)
ZHU WEI (CN)
International Classes:
C07C229/28; C07C221/00; C07C227/22; C07C231/10; C07C233/00; C07D221/20
Domestic Patent References:
| WO2006000562A1 | 2006-01-05 | |||
| WO2003002517A1 | 2003-01-09 |
Foreign References:
| US6846950B2 | 2005-01-25 | |||
| CN1471507A | 2004-01-28 | |||
| CN1109017C | 2003-05-21 | |||
| US20040034248A1 | 2004-02-19 | |||
| US20040063997A1 | 2004-04-01 |
Other References:
See also references of EP 1939170A4
Attorney, Agent or Firm:
NTD PATENT & TRADEMARK AGENCY LIMITED BEIJING OFFICE (Block A Investment Plaz, 27 Jinrongdajie 2 Beijing, CN)
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