This invention discloses a process for converting gabapentin acid salt to free gabapentin, where the salt is dissolved in an organic solvent in which both gabapentin acid salt and free gabapentin are soluble. The solution is treated with a powdered alkaline base to liberate free gabapentin which will remain in solution. The insoluble alkali salt of the acid is removed by filtration. From the filtrate free gabapentin is obtained either by adding anti-solvent or by extraction with water.
[EN] PROCESS FOR THE PURIFICATION OF GABAPENTIN<br/>[FR] PROCESSUS DE PURIFICATION DE GABAPENTINE
申请人:ZAMBON SPA
公开号:WO2005058797A1
公开(公告)日:2005-06-30
A process for the preparation of gabapentin comprising the passage of a salt of the same through a ionic exchange resin of strong cationic type, the elution of the gabapentin which has fixed onto the column and the crystallization from organic solvent, characterized in that the resin is regenerated by using a mineral acid in a molar quantity between 50 and 90%, is described.
[EN] PROCESS FOR PREPARING GABAPENTIN<br/>[FR] PROCEDE POUR L'ELABORATION DE GABAPENTINE
申请人:TARO PHARMA IND
公开号:WO2003089403A1
公开(公告)日:2003-10-30
The present invention provides compositions and methods of preparing gabapentin that includes (a) subjecting cyclohexanediacetic acid monoamide to a Hofmann rearrangement to yield a solution comprising an isocyanate intermediate; (b) hydrolyzing the isocyanate intermediate in the presence of an alkali base to form a gabapentin alkali salt; (c) converting the gabapentin alkali salt to a gabapentin-amine salt in a water-miscible polar solvent; (d) adding a basic or weakly basic ion exchange resin to a solution comprising the gabapentin-amine salt; (e) removing the ion exchange resin from the solution; and (f) concentrating the solution to yield gabapentin.
[EN] IMPROVED PROCESS FOR PREPARATION OF GABAPENTIN<br/>[FR] PROCEDE AMELIORE POUR LA PREPARATION DE GABAPENTINE
申请人:NICHOLAS PIRAMAL INDIA LTD
公开号:WO2004046084A1
公开(公告)日:2004-06-03
A process for producing Gabapentin, (1-(aminomethyl)-1-cyclohexaneacetic acid) from Gabapentin hydrochloride salt. In the process the Gabapentin hydrochloride is converted to Gabapentin using inorganic base such as Barium hydroxide. Gabapentin hydrochloride is converted to Gabapentin sulfate which in turn is converted to free base using Barium hydroxide. The process is directed to improvement in the manufacture of Gabapentin which would be industrially feasible and effective Gabapentin obtained following the process of the invention is suitable as a drug especially in the treatment of cerebral diseases such as epilepsy. The above process involves simple steps and avoid the problems of the known art. In particular the process avoids severe conditions and/or complexities and can be readily adopted for industrial application. The process provides for good yield and does not involve lenghty extended process steps. It is cost-effective and can be carried out involving simple ingredients and steps of manufacture.
The present invention provides compositions and methods of preparing gabapentin that includes (a) subjecting cyclohexanediacetic acid monoamide to a Hofmann rearrangement to yield a solution comprising an isocyanate intermediate; (b) hydrolyzing the isocyanate intermediate in the presence of an alkali base to form a gabapentin alkali salt; (c) converting the gabapentin alkali salt to a gabapentin-amine salt in a water-miscible polar solvent; (d) adding a basic or weakly basic ion exchange resin to a solution comprising the gabapentin-amine salt; (e) removing the ion exchange resin from the solution; and (f) concentrating the solution to yield gabapentin.