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US3974031A
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Process for producing L-cysteine or its derivatives
Assignee: Mitsubishi Chemical Corp
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Filing: 1975-05-06
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Granted: 1976-08-10
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Expires: 1995-05-06
Abstract
Abstract L-cysteine and derivatives thereof of the formula (I): RS-CH2CHCOOH (I) ¦ NH2 wherein R is selected from the group consisting of hydrogen, C1-C15 alkyl, C2-C15 alkenyl, C6-C15 aryl, C7-C15 aralkyl, are prepared by a process which comprises reacting beta -substituted L-alanine having the formula (II): X-CH2CHCOOH (II) ¦ NH2 wherein X is selected from the group consisting of halogen, -OR' and -SR'; wherein R' is selected from the group consisting of hydrogen, allyl, C1-C15 alkyl, C6-C15 aryl and C7-C15 aralkyl, with a thiol, or hydrogen sulfide, of the formula (III):
Inventors
- 👤 Hideaki Yamada
- 👤 Hidehiko Kumagai
- 👤 Haruyiki Ohkishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:15
CPC Classifications
C; C12; C12P; C12P13/00; C12P13/04; C12P13/12; C12N; C12N9/00; C12N9/88; Y; Y10; Y10S; Y10S435/00; Y10S435/814; Y10S435/815; Y10S435/816; Y10S435/8215; Y10S435/822; Y10S435/83; Y10S435/84; Y10S435/843; Y10S435/848; Y10S435/849; Y10S435/852; Y10S435/859; Y10S435/873; Y10S435/874; Y10S435/876; Y10S435/879; Y10S435/88; Y10S435/881
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
156 words
A process for producing L-cysteine and derivatives thereof of the formula (I): ##EQU3## wherein R is selected from the group consisting of hydrogen, C 1 - C 15 alkyl, C 2 - C 15 alkenyl, C 6 - C 15 aryl, C 7 - C 15 aralkyl, which comprises reacting β-substituted-L-alanine having the formula (II): ##EQU4## wherein X is selected from the group consisting of halogen, --OR' and --SR', erein R' is selected from the group consisting of hydrogen, allyl, C 1 - C 15 alkyl, C 6 - C 15 aryl and C 7 - C 15 aralkyl, with a thiol, or hydrogen sulfide, of the formula (III): r -- sh (iii) wherein R is as defined above, ammonium hydrosulfide or a metal hydrosulfide of the formula (IV): r -- s -- y (iv) wherein R is hydrogen, and Y is ammonium or a metal, in an aqueous medium, in the presence of cysteine desulfhydrase.
Claim 2
Dependent Claim
156 words
A process for producing L-cysteine and derivatives thereof of the formula (I): ##EQU3## wherein R is selected from the group consisting of hydrogen, C 1 - C 15 alkyl, C 2 - C 15 alkenyl, C 6 - C 15 aryl, C 7 - C 15 aralkyl, which comprises reacting β-substituted-L-alanine having the formula (II): ##EQU4## wherein X is selected from the group consisting of halogen, --OR' and --SR', erein R' is selected from the group consisting of hydrogen, allyl, C 1 - C 15 alkyl, C 6 - C 15 aryl and C 7 - C 15 aralkyl, with a thiol, or hydrogen sulfide, of the formula (III): r -- sh (iii) wherein R is as defined above, ammonium hydrosulfide or a metal hydrosulfide of the formula (IV): r -- s -- y (iv) wherein R is hydrogen, and Y is ammonium or a metal, in an aqueous medium, in the presence of cysteine desulfhydrase.
Claim 3
Dependent Claim
71 words
The process of claim 1, wherein L-cysteine is produced by the reaction of β-substituted L-alanine of the formula (II) with a compound selected from the group consisting of hydrogen sulfide, ammonium hydrosulfide, a water-soluble metal hydrosulfide of the formula (IV), ammonium sulfide whereby ammonium hydrosulfide and/or hydrogen sulfide is produced in the aqueous medium, and a metal sulfide whereby said metal hydrosulfide and/or hydrogen sulfide is produced in the aqueous medium.
Claim 4
Dependent Claim
33 words
The process of claim 1, wherein the derivative of L-cysteine of the formula (I) is produced by the reaction of β-substituted L-alanine of the formula (II) with a thiol of the formula (III).
Claim 5
Dependent Claim
28 words
The process of claim 1, wherein R is selected from the group consisting of hydrogen, C 1 - C 5 alkyl and C 2 - C 5 alkenyl.
Claim 6
Dependent Claim
20 words
The process of claim 4, wherein R is selected from the group consisting of hydrogen, methyl, ethyl, n-propyl and allyl.
Claim 7
Dependent Claim
23 words
The process of claim 1, wherein R' is selected from the group consisting of hydrogen, allyl, and C 1 - C 5 alkyl.
Claim 8
Dependent Claim
18 words
The process of claim 6, wherein R' is selected from the group consisting of hydrogen, allyl and methyl.
Claim 9
Dependent Claim
9 words
The process of claim 1, wherein X is chlorine.
Claim 10
Dependent Claim
50 words
The process of claim 1, wherein ammonium sulfide which produces ammonium hydrosulfide and/or hydrogen sulfide in the aqueous medium or a water-soluble metal sulfide which produces a water-soluble metal hydrosulfide and/or hydrogen sulfide in the aqueous medium, is employed instead of hydrogen sulfide, ammonium hydrosulfide or a water-soluble metal hydrosulfide.
Claim 11
Dependent Claim
27 words
The process of claim 9, wherein said metal sulfide is selected from the group consisting of a sulfide of an alkali metal and an alkaline earth metal.
Claim 12
Dependent Claim
25 words
The process of claim 10, wherein said metal sulfide is selected from the group consisting of sodium sulfide, potassium sulfide, calcium sulfide and barium sulfide.
Claim 13
Dependent Claim
11 words
The process of claim 1, wherein said metal hydrosulfide is water-soluble.
Claim 14
Dependent Claim
27 words
The process of claim 12, wherein said metal hydrosulfide is selected from the group consisting of a hydrosulfide of an alkali metal and an alkaline earth metal.
Claim 15
Dependent Claim
21 words
The process of claim 13, wherein said metal hydrosulfide is selected from the group consisting of sodium hydrosulfide and potassium hydrosulfide.
Claim 16
Dependent Claim
37 words
The process of claim 1, wherein cysteine desulfhydrase is derived from a microorganism selected from the group consisting of Brevibacterium, Sarcina, Corynebacterium, Arthrobacter, Pseudomonas, Proteus, Micrococcus, Escherichia, Serratia, Alcaligenes, Bacillus, Agrobacterium, Enterobacter (Aerobacter), Citrobacter, Klebsiella and Salmonella.
Claim 17
Dependent Claim
37 words
The process of claim 1, wherein the reaction is carried out at a temperature of 30° - 50°C for a period of 2 - 48 hours in an aqueous medium having a pH of 7 - 11.
Claim 18
Dependent Claim
18 words
The process of claim 1, wherein 1 - 5 g/l of dried cells containing cysteine desulfhydrase is employed.
Claim 19
Dependent Claim
28 words
The process of claim 1, wherein the concentrations of β-substituted L-alanine, and the thiol, hydrogen sulfide, ammonium hydrosulfide or metal hydrosulfide are each 3 - 20 weight percent.
Claim 20
Dependent Claim
29 words
The process of claim 1, wherein said aqueous medium additionally contains a carbonyl compound containing 1 to 20 carbon atoms in a concentration of from 0.05 - 10 M.
Claim 21
Dependent Claim
43 words
The process of claim 19, wherein said carbonyl compound is selected from the group consisting of an α-keto carboxylic acid containing 3 to 20 carbon atoms, an aldehyde containing 1 to 20 carbon atoms, and a ketone containing 3 to 20 carbon atoms.
Claim 22
Dependent Claim
39 words
The process of claim 20, wherein said α-keto carboxylic acid, aldehyde or ketone is selected from the group consisting of benzaldehyde, isobutyraldehyde, acetone, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, benzophenone, benzil, pyruvic acid, 2-oxobutyric acid and 2-oxoglutaric acid.
Claim 23
Dependent Claim
25 words
The process of claim 1, wherein said reaction is carried out in the presence of pyridoxal phosphate in a concentration of up to 0.01 mM.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-10 | 1980-02-09 | 1980-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-10 | 1984-02-09 | 1984-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-10 | 1988-02-09 | 1988-08-10 | $7700.00 | Window Closed / Lapsed |