Patent US3883554A successfully refreshed from Google Patents.
US3883554A
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US
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Process for preparing 5-hydroxy-tryptophan and its derivatives
Assignee: KH Neochem Co Ltd
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Filing: 1973-05-08
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Granted: 1975-05-13
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Expires: 1993-05-08
Abstract
Abstract 5-HYDROXYTRYPTOPHAN AND ITS DERIVATIVES ARE PREPARED BY OXIDATION OF 2,3-DIHYDROTRYPTOPHAN OR ITS DERIVATIVES. 5HYDROXYTRYPTOPHAN IS USEFUL AS AN ANTIOXIDANT FOR FOODSTUFFS AND MEDICINES.
Inventors
- 👤 Yasuki Mori
- 👤 Moriyuki Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:53
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/04; C07D209/10; C07D209/18; C07D209/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
11 words
A PROCESS FOR THE PREPARATION OF A COMPOUND OF THE FORMULA:
Claim 2
Dependent Claim
11 words
A PROCESS FOR THE PREPARATION OF A COMPOUND OF THE FORMULA:
Claim 3
Dependent Claim
11 words
A process for the preparAtion of a compound of the formula:
Claim 4
Dependent Claim
11 words
A process for the preparAtion of a compound of the formula:
Claim 5
Dependent Claim
19 words
The process for the preparation of 5-hydroxy-L-tryptophan which comprises oxidizing 2,3-dihydrotryptophan with potassium nitrosodisulfonate in water at room temperature.
Claim 6
Dependent Claim
19 words
The process for the preparation of 5-hydroxy-L-tryptophan which comprises oxidizing 2,3-dihydrotryptophan with potassium nitrosodisulfonate in water at room temperature.
Claim 7
Dependent Claim
14 words
The process of claim 2 wherein the hydrolysis is carried out with dilute acid.
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) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |