Process to produce (1r,4r)-4-substituted cyclohexane-1-amines

Patent metadata

Field	Value
Publication number	US-2025122542-A1
Application number	US-202218689627-A
Country	US
Kind code	A1
Filing date	Sep 14, 2022
Priority date	Sep 15, 2021
Publication date	Apr 17, 2025
Grant date	—

Abstract

The invention relates to a process to produce a (1r,4r)-4-substituted cyclohexane-1-amine [further referred as trans-4-substituted cyclohexane-1-amine] of formula (T), starting from a diastereomeric mixture of 4-substituted cyclohexane-1-amines (formula (C)+formula (T)) or any salt of them by using a single transaminase biocatalyst in whole-cell, soluble or immobilized form in the presence of an amine acceptor used in sub-equimolar up to equimolar quantities in batch mode or in continuous-flow mode. In the first aspect of the present invention 2-(trans-4-aminocyclohexyl)acetic acid esters, more preferably a C 1-6 alkyl esters, particularly 2-(trans-4-aminocyclohexyl)acetic acid ethyl ester may be produced. In the second aspect of the present invention hydroxyl-protected or protective group-free trans-4-(2-hydroxyethyl)cyclohexan-1-amines, particularly trans-4-(2-hydroxyethyl)cyclohexan-1-amine may be produced. In the third aspect of the present invention protected 2-(trans-4-aminocyclohexyl)acetaldehydes, particularly trans-4-((1,3-dioxolan-2-yl)methyl)cyclohexan-1-amine may be produced.

First claim

1 . A process of producing (1r,4r)-4-substituted cyclohexane-1-amine of formula (T) or a salt thereof

where in G represents a substituent, selected from
a hydrogen atom;
a C 1-6 alkyl group;
an ester moiety (—COOR), wherein R represents an alkyl, aralkyl, or aryl group;
a CH 2 —OR′ group, wherein R′ represents a hydrogen atom or a hydroxyl protecting group;
a group of formula

wherein n is an integer of 1 to 2;
a substituted or unsubstituted aryl group; or
an aralkyl group,
the process comprising:
reacting a diastereomeric mixture of 4-substituted cyclohexane-1-amines (formula (C)+formula (T)) or salts thereof

with a single transaminase biocatalyst in whole-cell, soluble, or immobilized form in the presence of an amine acceptor used in a sub-equimolar or equimolar quantity.

2 . The process according to claim 1 characterized in that the reaction is carried out in batch mode or in continuous-flow mode.

3 . (canceled)

4 . The process according to claim 1 characterized in that the diastereomeric mixture of 4-substituted cyclohexane-1-amines (formula (C)+formula (T)) is in hydrochloride salt form (formula (C·HCl)+formula (T·HCl)).

5 . (canceled)

6 . The process according to claim 1 characterized in that a transaminase biocatalyst comprising an amino acid sequence with at least about 37% sequence identity to Chromobacterium violaceum transaminase mutant (W60C) (CvS W60C -TA: SEQ ID NO. 1) or to Vibrio fluvialis transaminase (VfS-TA: SEQ ID NO. 2) over a region of at least about 100 residues is used.

7 .- 11 . (canceled)

12 . The process according to claim 1 characterized in that a ketone or aldehyde is used as the amine acceptor in a sub-equimolar amount.

13 . The process according to claim 1 characterized in that a 4-substituted cyclohexanone of formula K

wherein G is as described in claim 1 for formula (C) and formula (T), is used as the amine acceptor-ketene.

14 . The process according to claim 1 characterized in that the diastereomeric mixture consists of 2-(4-aminocyclohexyl)acetic acid esters of formula (I) and formula (II) or salts thereof

wherein R represents an alkyl, aralkyl, or aryl group.

15 . The process according to claim 14 characterized in that sodium pyruvate is used as the amine acceptor in a sub-equimolar amount.

16 . The process according to claim 14 characterized in that a 4-substituted cyclohexanone of formula (III) is used as the amine acceptor

wherein R represents an alkyl, aralkyl, or aryl group.

17 .- 19 . (canceled)

20 . The process according to claim 14 characterized in that the transaminase biocatalyst is a Chromobacterium violaceum mutant (W60C) transaminase/CvS W60C -TA, characterized by SEQ ID NO. 1/used in whole-cell form, immobilized whole-cell form, soluble cell-free form, or immobilized cell-free form, and wherein the transaminase biocatalyst is used in batch mode.

21 . (canceled)

22 . The process according to claim 14 characterized in that the transaminase biocatalyst is a Vibrio fluvialis transaminase/VfS-TA, characterized by SEQ ID NO. 2/used in whole-cell form, immobilized whole-cell form, soluble cell-free form, or immobilized cell-free form, and wherein the transaminase biocatalyst is used in batch mode.

23 - 24 . (canceled)

25 . The process according to claim 14 characterized in that the diastereomeric mixture consists of 2-(4-aminocyclohexyl)acetic acid ethyl ester hydrochloride salt (formula Ib·HCl+formula IIb·HCl) and pure 2-(trans-4-aminocyclohexyl)acetic ethyl ester (formula Ib) is produced.

26 . The process according to claim 14 characterized in that the diastereomeric mixture consists of 2-(4-aminocyclohexyl)acetic acid isopropyl ester hydrochloride salt (formula Id·HCl+formula IId·HCl) and pure 2-(trans-4-aminocyclohexyl)acetic isopropyl ester (formula Id) is produced.

27 . The process according to claim 1 characterized in that the diastereomeric mixture consists of 2-(4-aminocyclohexyl)ethan-1-ol derivatives of formula (IV) and formula (V) or salts thereof

wherein R′ represents a hydrogen atom or hydroxyl-protecting group.

28 . The process according to claim 27 characterized in that sodium pyruvate is used as the amine acceptor in a sub-equimolar amount.

29 . The process according to claim 27 characterized in that a 4-substituted cyclohexanone of formula (VI) is used as the amine acceptor

wherein R′ represents a hydrogen atom or hydroxyl-protecting group.

30 . (canceled)

31 . The process according to claim 27 characterized in that a Chromobacterium violaceum mutant (W60C) enzyme/CvS W60C -TA, characterized by SEQ ID NO. 1/is used as the transaminase biocatalyst in batch mode.

32 . (canceled)

33 . The process according to claim 27 characterized in that a Vibrio fluvialis enzyme/VfS-TA, characterized by SEQ ID NO. 2/is used as the transaminase biocatalyst in batch mode.

34 . (canceled)

35 . The process according to claim 27 characterized in that a cis-selective Chromobacterium violaceum transaminase mutant (W60C)/CvS W60C -TA/is used in continuous-flow mode.

36 .- 37 . (canceled)

38 . The process according to claim 1 characterized in that the starting diastereomeric mixture consists of 2-(4-aminocyclohexyl)acetaldehyde derivatives of formula (VII) and formula (VIII) or salts thereof

wherein n is an integer of 1 to 2.

39 . (canceled)

40 . The process according to claim 38 characterized in that a 4-substituted cyclohexanone of formula (IX) is used as the amine acceptor ketene

wherein n is an integer of 1 to 2.

41 . The process according to claim 38 characterized in that the Chromobacterium violaceum mutant (W60C) enzyme/CvS W60C -TA, characterized by SEQ ID NO. 1/is used as the transaminase biocatalyst in batch mode.

42 . (canceled)

43 . The process according to claim 38 characterized in t

Assignees

• Richter Gedeon Nyrt
• Budapesti Mueszaki Es Gazdasagtudomanyi Egyetem

Inventors

• Farkas Emese
• Poppe László
• Hornyánszky Gábor
• Incze Dániel János
• Éles János
• Sánta-Bell Evelin
• Molnár Zsófia Klára
• Szemes József
• Schneider Anna
• Csuka Pál

Classifications

• C12P41/006

  by reactions involving C-N bonds, e.g. nitriles, amides, hydantoins, carbamates, lactames, transamination reactions, or keto group formation from racemic mixtures · CPC title

• C12P17/04

  containing a five-membered hetero ring, e.g. griseofulvin {, vitamin C} · CPC title

• C12P13/001 Primary

  Amines; Imines · CPC title

• C12P17/02

  Oxygen as only ring hetero atoms · CPC title

• C07C213/10

  Separation; Purification; Stabilisation; Use of additives · CPC title