US5072041A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optically active n-hydroxy-alpha-amino acids, amides and their derivatives
Assignee: DSM BV
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Filing: 1989-11-01
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Granted: 1991-12-10
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Expires: 2009-11-01
Abstract
Abstract The invention relates to a process for the preparation of N-hydroxy-alpha-amino acids and the derivatives thereof by reacting a derivative of an alpha-amino acid with an aromatic aldehyde to form a Schiff base, oxidizing the Schiff base to an oxaziridine and converting the oxaziridine into the corresponding N-hydroxy-alpha-amino acid derivative and, if so desired, converting that derivative into the acid or a different derivative, in which an alpha-amino acid amide is used as starting material.
Inventors
- 👤 Johan Kamphuis
- 👤 Wilhelmus H. J. Boesten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:28
CPC Classifications
C; C07; C07C; C07C239/00; C07C239/08; C07C239/18
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
84 words
The D- or L- stereo-isomer of a compound with the formula ##STR3## in substantially optically pure form, in which R 1 represents H, acyclic or cyclic alkyl or carbocyclic aryl and R 2 represents H, acyclic or cyclic alkyl or carbocyclic aryl, with the following proviso regarding combinations of R 1 and R 2 : R 1 and R 2 are not, respectively, H and H; nor CH 3 and CH 3 ; nor H and CH 3 ; nor CH 3 and H.
Claim 2
Dependent Claim
84 words
The D- or L- stereo-isomer of a compound with the formula ##STR3## in substantially optically pure form, in which R 1 represents H, acyclic or cyclic alkyl or carbocyclic aryl and R 2 represents H, acyclic or cyclic alkyl or carbocyclic aryl, with the following proviso regarding combinations of R 1 and R 2 : R 1 and R 2 are not, respectively, H and H; nor CH 3 and CH 3 ; nor H and CH 3 ; nor CH 3 and H.
Claim 3
Dependent Claim
19 words
A compound according to claim 1, in which one of the symbols R 1 and R 2 represents H.
Claim 4
Dependent Claim
7 words
L-N-hydroxy-phenylglycine amide, in substantially optically pure form.
Claim 5
Dependent Claim
7 words
L-N-hydroxy-phenylglycine amide, in substantially optically pure form.
Claim 6
Dependent Claim
7 words
D-N-hydroxy-phenylglycine amide, in substantially optically pure form.
Claim 7
Dependent Claim
7 words
D-N-hydroxy-phenylglycine amide, in substantially optically pure form.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-12-09 | 1995-06-10 | 1995-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-09 | 1999-06-10 | 1999-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-09 | 2003-06-10 | 2003-12-10 | $7700.00 | Window Closed / Lapsed |