process for the enzymatic reduction of enoates

Abstract

A process for the enzymatic reduction of an enoate (1) wherein the C═C bond of the enoate (1) is stereoselectively hydrogenated in the presence of an enoate-reductase and an oxidizable co-substrate (2) in a system which is free of NAD(P)H, a. b. in which c. A is a ketone radical (—CRO), an aldehyde radical (—CHO), a carboxyl radical (—COOR), with R═H or optionally substituted C 1 -C 6 -alkyl radical, d. R 1 , R 2 and R 3 are independently of one another H, —O-C 1 -C 6 -alkyl , —O—W with W=a hydroxyl protecting group, C 1 -C 6 -alkyl, which can be substituted, C 2 -C 6 -alkenyl, carboxyl, or an optionally substituted carbo- or heterocyclic, aromatic or nonaromatic radical, or one of R 1 , R 2 and R 3 is a —OH radical, or R 1 is linked to R 3 so as to become part of a 4-8-membered cycle, or R 1 is linked to R so as to become part of a 4-8-membered cycle, with the proviso that R 1 , R 2 and R 3 may not be identical.

1 . A process for the enzymatic reduction of an enoate (1), wherein the C═C bond of the enoate (1) is stereoselectively hydrogenated in the presence of an enoate-reductase and an oxidizable co-substrate (2) in a system which is free of NAD(P)H, 
       
         
           
           
               
               
           
         
       
       in which
 A is a ketone radical (—CRO), an aldehyde radical (—CHO), a carboxyl radical (—COOR), with R═H or optionally substituted C 1 -C 6 -alkyl radical, R 1 , R 2  and R 3  are independently of one another H, —O-C 1 -C 6 -alkyl, —O—W with W=a hydroxyl protecting group, C 1 -C 6 -alkyl, which can be substituted, C 2 -C 6 -alkenyl, carboxyl, or an optionally substituted carbo- or heterocyclic, aromatic or nonaromatic radical, or one of R 1 , R 2  and R 3  is a —OH radical, or R 1  is linked to R 3  so as to become part of a 4-8-membered cycle, or R 1  is linked to R so as to become part of a 4-8-membered cycle, with the proviso that R 1 , R 2  and R 3  may not be identical. 
 
     
     
         2 . The process according to  claim 1 , wherein the enoate reductase is selected from a reductase
 (i) comprising at least one of the polypeptide sequences SEQ ID NO:1, 2, 3, 4 or   (ii) with a functionally equivalent polypeptide sequence which has at least 80% sequence identity with SEQ ID NO:1, 2, 3 or 4.   
     
     
         3 . The process according to  claim 1 , wherein the enoate (1) has the general formula SEQ ID NO: 1, 2, 3 or 4. 
     
     
         4 . The process according to  claim 1 , wherein the co-substrate (2) is identical with the enoate (1). 
     
     
         5 . The process according to  claim 1 , wherein a molar ratio of enoate (1) to co-substrate (2) is from 1:1 to 1:3. 
     
     
         6 . The process according to  claim 1 , wherein the C═C bond of the enoate (1) is enantioselectively or diastereoselectively hydrogenated. 
     
     
         7 . The process according to  claim 2 , wherein the C═C bond of the enoate (1) is enantioselectively or diastereoselectively hydrogenated. 
     
     
         8 . The process according to  claim 3 , wherein the C═C bond of the enoate (1) is enantioselectively or diastereoselectively hydrogenated. 
     
     
         9 . The process according to  claim 4 , wherein the C═C bond of the enoate (1) is enantioselectively or diastereoselectively hydrogenated. 
     
     
         10 . The process according to  claim 5 , wherein the C═C bond of the enoate (1) is enantioselectively or diastereoselectively hydrogenated.