Novel intermediate for the synthesis of prostaglandins

Abstract

An enantiomerically enriched compound of formula 1, wherein Ar is phenyl optionally substituted with one or more groups selected from haloalkyl, alkyl and halide. This compound can be isolated in crystalline form, and used in the preparation of (+)-16-[3-trifluoromethyl)phenoxy]-17,18,19,20-tetranor PGF 2α isopropyl ester.

We claim:  
     
         1 . A process for preparing a prostaglandin, or an ester derivative thereof, wherein said process comprises the conversion of a lactone compound of formula 1  
       
         
           
           
               
               
           
         
       
       wherein Ar is phenyl optionally substituted with one or more groups selected from haloalkyl, alkyl and halide; and wherein said conversion to said prostaglandin comprises the following steps: 
 (i) reduction of the lactone to the corresponding lactol,  
 (ii) introduction of a prostaglandin α-chain by a Wittig reaction, and  
 (iii) conversion of the OTBDMS groups to OH groups.  
 
     
     
         2 . The process according to  claim 1 , wherein the prostaglandin is (+)-16-[3-trifluoromethyl)phenoxy]-17,18,19,20-tetranor PGF 2a  isopropyl ester.  
     
     
         3 . The process, according to  claim 1 , wherein said process further comprises an acid-ester conversion either before or after step (Iii).