US4267344A
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N-Substituted N-carboxyanhydrides of α-amino acids and their application in the preparation of peptides
Assignee: Proteinkemisk Inst Tilknyttet Akademiet for de Tekniske Videnska
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Filing: 1978-11-20
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Granted: 1981-05-12
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Expires: 1998-11-20
Abstract
Abstract N-Substituted N-carboxyanhydrides of α-amino acids, useful in peptide syntheses, and peptide synthesis process using such compounds, are disclosed. The N-substituent is penta(lower alkoxy)benzyl, or optionally substituted 9-xanthyl, 9-thioxanthyl or 9-selenoxanthyl.
Inventors
- 👤 John B. Halstrom
- 👤 Karoly G. Kovacs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:15
CPC Classifications
C; C07; C07D; C07D263/00; C07D263/02; C07D263/30; C07D263/34; C07D263/44; C07D311/00; C07D311/02; C07D311/78; C07D311/80; C07D311/82; C07D311/84; C07D311/88; C07D335/00; C07D335/04; C07D335/10; C07D335/12; C07D335/14; C07D335/18; C07K; C07K5/00; C07K5/04; C07K5/06; C07K5/06008; C07K5/06017; C07K5/06034; C07K5/06052
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
76 words
N-substituted N-carboxyanhydrides of α-amino acids, having the general formula I ##STR13## wherein R designates hydrogen or the side-chain of an α-amino acid, any functional group or functional groups in said side-chain being optionally protected, R 1 and R 2 together with the adjacent carbon atom designates R 9 -xanthyl-, R 9 -thioxanthyl- or 9-selenoxanthyl group, said group being optionally substituted in positions other than 1 and 8 with probably lower alkyl, lower alkoxy, nitro, or chloro.
Claim 2
Dependent Claim
76 words
N-substituted N-carboxyanhydrides of α-amino acids, having the general formula I ##STR13## wherein R designates hydrogen or the side-chain of an α-amino acid, any functional group or functional groups in said side-chain being optionally protected, R 1 and R 2 together with the adjacent carbon atom designates R 9 -xanthyl-, R 9 -thioxanthyl- or 9-selenoxanthyl group, said group being optionally substituted in positions other than 1 and 8 with probably lower alkyl, lower alkoxy, nitro, or chloro.
Claim 3
Dependent Claim
64 words
N-substituted N-carboxyanhydrides of α-amino acids as claimed in claim 1, having the general formula ##STR14## wherein R is as defined in claim 1, X designates an oxygen, sulfur, or selenium atom, and the substituents Y are the same or different and each designate hydrogen, lower alkyl, lower alkoxy, nitro, or chloro, with the proviso that at least two of the symbols Y designate hydrogen.
Claim 4
Dependent Claim
20 words
N-substituted N-carboxyanhydrides of α-amino acids as claimed in claim 2, wherein X is oxygen, and each symbol Y designates hydrogen.
Claim 5
Dependent Claim
17 words
N-substituted N-carboxyanhydrides as claimed in claim 2, wherein X is sulfur, and each symbol Y designates hydrogen.
Claim 6
Dependent Claim
17 words
N-substituted N-carboxyanhydrides as claimed in claim 2, wherein X is selenium, and each symbol Y designates hydrogen.
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) | 1984-05-11 | 1984-11-10 | 1985-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-11 | 1988-11-10 | 1989-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-11 | 1992-11-10 | 1993-05-12 | $7700.00 | Window Closed / Lapsed |