EP0057092A1
Expired / Lapsed
EP
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Process for racemizing an optically active alpha-amino acid or a salt thereof
Assignee: Tanabe Pharma Corp
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Filing: 1982-01-22
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Granted: —
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Expires: 2002-01-22
Abstract
Abstract A process for producing a DL-a-amino acid or a salt thereof which comprises racemizing an optically active a-amino acid or a salt thereof in the presence of an aliphatic acid and an aldehyde.
Inventors
- 👤 Ichiro Chibata
- 👤 Shigeki Yamada
- 👤 Chikara Hongo
- 👤 Ryuzo Yoshioka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 22:31
CPC Classifications
C; C07; C07C; C07C227/00; C07C227/36; C07B; C07B55/00; C07C227/38; C07C227/44; C07C229/00; C07C229/02; C07C229/04; C07C229/06; C07C229/08
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
33 words
A process for producing a DL-α-amino acid or a salt thereof which comprises racemizing an optically active α-amino acid or a salt thereof in the presence of an aliphatic acid and an aldehyde.
Claim 2
Dependent Claim
33 words
A process for producing a DL-α-amino acid or a salt thereof which comprises racemizing an optically active α-amino acid or a salt thereof in the presence of an aliphatic acid and an aldehyde.
Claim 3
Dependent Claim
33 words
A process according to claim 1 wherein the aliphatic acid is a compound of the formula: R 1- COOH (I) wherein R 1 is hydrogen or alkyl of one to 4 carbon atoms,
Claim 4
Dependent Claim
31 words
A process according to claim 2 wherein the aliphatic acid is a compound of the formula (I) in which R 1 is hydrogen or alkyl of one to 3 carbon atoms.
Claim 5
Dependent Claim
16 words
A process according to claim 3 wherein the aliphatic acid is acetic acid or propionic acid.
Claim 6
Dependent Claim
66 words
A process according to any of claims 1 to 4 wherein the aldehyde is a compound of the formula . R 2 -CHO wherein R 2 is hydrogen; alkyl of one to six carbon atoms; alkenyl of two to four carbon atoms; phenyl; phenyl having at least one hydroxy, nitro, amino or alkoxy of one to four carbon atoms substituent; phenylvinyl; oxygen-containing heteromonocyclic group or hydroxynaphthyl.
Claim 7
Dependent Claim
32 words
A process according to claim 5 wherein R 2 is hydrogen; alkyl of one to six carbon atoms; vinyl; phenyl; phenyl having at least one hydroxy, nitro or methoxy substituent; or phenyl.
Claim 8
Dependent Claim
24 words
A process according to claim 6 wherein the aldehyde is formaldehyde, acetaldehyde, propionaldehyde n-butyraldehyde, n-heptylaldehyde, acrolein, benzaldehyde, salicylaldehyde, p-hydroxybenzaldehyde, p-anisaldehyde, o-nitrobenzaldehyde, 5-nitrosalicylaldehyde or furfural.
Claim 9
Dependent Claim
15 words
A process according to claim 7 wherein the aldehyde is propionaldehyde, n-butyraldehyde, benzaldehyde or salicylaldehyde.
Claim 10
Dependent Claim
21 words
A process according to any of claims 1 to 8 wherein the racemization reaction is carried out at 20° to 120°C.
Claim 11
Dependent Claim
18 words
A process according to claim 9 wherein the racemization reaction is carried out at 40 0 to 100°C.
Claim 12
Dependent Claim
18 words
A process according to claim 10 wherein the racemization reaction is carried out at 60 0 to 100°C.
Claim 13
Dependent Claim
32 words
A process according to any of claims 1 to 11 wherein 0.001 to 0.5 mole of the aldehyde per mole of the optically active α-amino acid or a salt thereof is used.
Claim 14
Dependent Claim
29 words
. A process according to claim 12 wherein 0.005 to 0.2 mole of the aldehyde per mole of the optically active α-amino ,acid or a salt thereof is used.
Claim 15
Dependent Claim
28 words
A process according to claim 13 wherein 0.01 to 0.2 mole of the aldehyde per mole of the optically active α-amino acid or a salt thereof is used.
Claim 16
Dependent Claim
33 words
A process according to any of claims 1 to 14 wherein 2 to 50 g of the aliphatic acid per g of the optically active α-amino acid or a salt thereof are used.
Claim 17
Dependent Claim
43 words
A process according to any of claims 1 to 15 wherein the optically active α-amino acid is alanine, valine, leucine, isoleucine, serine, threonine, cystine, cysteine, methionine, tryptophan, phenylalanine, tyrosine, 3-(3,4-dihydroxyphenyl)alanine, phenylglycine, p-hydroxyphenylglycine, arginine, lysine, ornithine, histidine, aspartic acid, glutamic acid, proline or hydroxyproline.
Claim 18
Dependent Claim
35 words
A process according to any of claims 1 to 16 wherein the racemization reaction is carried out by contacting the optically active α-amino acid or a salt thereof with the aliphatic acid and the aldehyde.
Claim 19
Dependent Claim
44 words
A process according to any of claims 1 to 16 wherein the racemization reaction is carried out by stirring a mixture of the optically active α-amino acid or a salt thereof, the aliphatic acid and the aldehyde at a temperature of 20°C to 120°C.
Claim 20
Dependent Claim
46 words
- 19. A process according to any of claims 1 to 16 wherein the racemization reaction is carried out by stirring a mixture of the optically active p(-amino' acid or a salt thereof, the aliphatic acid and the aldehyde at a temperature of 40° to 100°C.
Claim 21
Dependent Claim
45 words
A process according to any of claims 1 to 16 wherein the racemization reaction is carried out by stirring a mixture of the optically active α-amino acid or a salt thereof, the aliphatic acid and the aldehyde at a temperature of 60° to 100°C. -
Claim 22
Dependent Claim
32 words
A process according to any of claims 1 to 20 wherein the racemization reaction of the optically active α-amino acid salt is carried out in the presence of a free DL-α-amino acid.
Claim 23
Dependent Claim
18 words
A process according to claim 21 wherein the free DL-α-amino acid corresponds to the optically active α-amino acid.
Claim 24
Dependent Claim
29 words
A process according to claim 21 or 22 wherein 0.001 to 0.8 mole of the free DL-α-amino acid per mole of the optically active α-amino acid salt is used.
Claim 25
Dependent Claim
25 words
A process according to claim 21, 22 or 23 wherein the free DL-α-amino acid is converted into the same salt as the racemized α-amino acid.
Claim 26
Dependent Claim
23 words
A process according to any of claims 1 to 24 wherein the racemization reaction is carried out in the presence of a solvent.
Claim 27
Dependent Claim
39 words
A process according to any of claims 1 to 25 wherein the aliphatic acid is used in the form of an aqueous solution and the concentration of the aliphatic acid in the solution is 10 to 100 v/v %.
Claim 28
Dependent Claim
22 words
A process according to claim 26 wherein the concentration of the aliphatic acid in the solution is 60 to 100 v/v %.
Claim 29
Dependent Claim
29 words
A process for producing a DL-α-amino acid or a salt thereof substantially as herein described with reference to and as illustrated in any of the foregoing Experiments or Examples.
Claim 30
Dependent Claim
29 words
A process for producing a DL-α-amino acid or a salt thereof substantially as herein described with reference to and as illustrated in any of the foregoing Experiments or Examples.
References Cited (Backward Citations)
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