Process 054

Abstract

The present invention is directed to a process for the preparation of a diastereomerically pure dibenzoyl-L-tartrate salt of a compound of formula (III) and to products of said process.

1 . A process for preparing a diastereomerically pure dibenzoyl-L-tartrate salt of a compound of formula (III) salt of a compound of formula (III) 
       
         
           
           
               
               
           
         
         comprising the steps of 
         (a) mixing a compound of formula (II) 
       
       
         
           
           
               
               
           
         
         with enantiomerically pure dibenzoyl-L-tartaric acid or its monohydrate to form a diastereoisomeric salt and 
         (b) crystallising said salt. 
       
     
     
         2 . A process according to  claim 1 , wherein the solvent in step (a) is selected from aliphatic alcohols; nitriles; polar ethers; aliphatic esters; polar aprotic solvents;
 water and mixtures thereof.   
     
     
         3 . A process according to  claim 2 , wherein the solvent in step (a) is a mixture of water and an aliphatic alcohol. 
     
     
         4 . A process according to  claim 3 , wherein the solvent in step (a) is a mixture of water and methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol or t-butanol. 
     
     
         5 . A process according to  claim 4 , wherein the solvent in step (a) is a mixture of water and ethanol. 
     
     
         6 . A mono-dibenzoyl-L-tartrate of the compound of formula (III). 
       
         
           
           
               
               
           
         
       
     
     
         7 . Use of a dibenzoyl-L-tartrate of the compound of formula (III) 
       
         
           
           
               
               
           
         
         in the preparation of {1S-[1α, 2α, 3β (1S*,2R*),5β]}-3-(7-{[2-(3,4-difluorophenyl)cyclopropyl]amino}-5-(propylthio)-3H-1,2,3-triazolo[4,5-d]pyrimidin-3-yl)-5-(2-hydroxyethoxy)cyclopentane-1,2-diol.