Patent US4293648A successfully refreshed from Google Patents.
US4293648A
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Process for esterification of α-L-aspartyl-L-phenylalanine
Assignee: Nutrasweet Co
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Filing: 1980-09-02
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Granted: 1981-10-06
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Expires: 2000-09-02
Abstract
Abstract A process for selectively esterifying α-L-aspartyl-L-phenylalanine to the corresponding alkyl esters using a proteolytic enzyme with specific esterase activity is described. The process is carried out in an aqueous-alcohol medium in which the alcohol concentration is sufficient to reverse the esterase activity. The α-L-aspartyl-L-phenylalanine alkyl esters so produced are useful as artificial sweeteners.
Inventors
- 👤 Arthur A. Davino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:59
CPC Classifications
C; C07; C07K; C07K5/00; C07K5/04; C07K5/06; C07K5/06104; C07K5/06113; C07K5/06121; C07K5/0613; C12; C12P; C12P21/00; C12P21/02; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
54 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting α-L-aspartyl-L-phenylalanine with an alcohol in the presence of an effective amount of a proteolytic enzyme with specific esterase activity in an aqueous alcohol medium at a pH of 4 to 7 in which the alcohol concentration is sufficient to reverse the hydrolytic activity of the protease.
Claim 2
Dependent Claim
54 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting α-L-aspartyl-L-phenylalanine with an alcohol in the presence of an effective amount of a proteolytic enzyme with specific esterase activity in an aqueous alcohol medium at a pH of 4 to 7 in which the alcohol concentration is sufficient to reverse the hydrolytic activity of the protease.
Claim 3
Dependent Claim
19 words
A process according to claim 1 wherein the proteolytic enzyme with specific esterase activity is a serine alkaline proteinase.
Claim 4
Dependent Claim
14 words
A process according to claim 2 wherein the serine alkaline proteinase is substilisin Carlsberg.
Claim 5
Dependent Claim
16 words
A process according to claim 2 wherein the alcohol is methanol in a concentration of 10-90%.
Claim 6
Dependent Claim
14 words
A process according to claim 4 wherein the serine alkaline proteinase is subtilisin Carlsberg.
Claim 7
Dependent Claim
36 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting α-L-aspartyl-L-phenylalanine with methanol in the presence of subtilisin Carlsberg serine alkaline proteinase in an aqueous-methanol medium at a pH of 5.0 in which the methanol concentration is 60%.
Claim 8
Dependent Claim
36 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting α-L-aspartyl-L-phenylalanine with methanol in the presence of subtilisin Carlsberg serine alkaline proteinase in an aqueous-methanol medium at a pH of 5.0 in which the methanol concentration is 60%.
Claim 9
Dependent Claim
59 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting N-protected-α-L-aspartyl-L-phenylalanine with an alcohol in the presence of an effective amount of a protease with specific esterase activity in an aqueous-alcohol medium at a pH of 4 to 7 in which the alcohol concentration is sufficient to reverse the hydrolytic activity of the protease followed by removal of the N-protecting group.
Claim 10
Dependent Claim
59 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting N-protected-α-L-aspartyl-L-phenylalanine with an alcohol in the presence of an effective amount of a protease with specific esterase activity in an aqueous-alcohol medium at a pH of 4 to 7 in which the alcohol concentration is sufficient to reverse the hydrolytic activity of the protease followed by removal of the N-protecting group.
Claim 11
Dependent Claim
19 words
A process according to claim 7 wherein the proteolytic enzyme with specific esterase activity is a serine alkaline proteinase.
Claim 12
Dependent Claim
14 words
A process according to claim 8 wherein the serine alkaline protease is subtilisin Carlsberg.
Claim 13
Dependent Claim
16 words
A process according to claim 7 wherein the alcohol is methanol in a concentration of 10-90%.
Claim 14
Dependent Claim
14 words
A process according to claim 10 wherein the serine alkaline proteinase is substilisin Carlsberg.
Claim 15
Dependent Claim
45 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting N-carbobenzoxy-α-L -aspartyl-L-phenylalanine with methanol in the presence of subtilisin Carlsberg serine alkaline proteinase in an aqueous-methanol medium at a pH of 5.0 in which the methanol concentration is 60% followed by removal of the carbobenzoxy protecting group.
Claim 16
Dependent Claim
45 words
A process for esterifying α-L-aspartyl-L-phenylalanine which comprises contacting N-carbobenzoxy-α-L -aspartyl-L-phenylalanine with methanol in the presence of subtilisin Carlsberg serine alkaline proteinase in an aqueous-methanol medium at a pH of 5.0 in which the methanol concentration is 60% followed by removal of the carbobenzoxy protecting group.
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) | 1984-10-05 | 1985-04-06 | 1985-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-05 | 1989-04-06 | 1989-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-05 | 1993-04-06 | 1993-10-06 | $7700.00 | Window Closed / Lapsed |