Patent US3271994A successfully refreshed from Google Patents.
Patent US2516145A successfully refreshed from Google Patents.
US2516145A
Expired / Lapsed
US
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Synthesis of n-carboanhydrides of alpha-amino acids
Assignee: EIDP Inc
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Filing: 1947-10-07
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Granted: 1950-07-25
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Expires: 1967-10-07
Abstract
No abstract record available.
Inventors
- 👤 William W Prichard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:25
CPC Classifications
C; C07; C07D; C07D263/00; C07D263/02; C07D263/30; C07D263/34; C07D263/44; C07D263/52
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
26 words
A METHOD FOR PREPARING N-CARBOANHYDRIDES OF ALPHA-AMINO ACIDS WHICH COMPRISES REACTING, UNDER ANHYDROUS CONDITIONS, THIONYL CHLORIDE WITH THE DIALKALI METAL SALT OF A HYDROCARBON ALPHA-CARBOXYAMINOCARBOXYLIC ACID.
Claim 2
Independent Claim
26 words
A METHOD FOR PREPARING N-CARBOANHYDRIDES OF ALPHA-AMINO ACIDS WHICH COMPRISES REACTING, UNDER ANHYDROUS CONDITIONS, THIONYL CHLORIDE WITH THE DIALKALI METAL SALT OF A HYDROCARBON ALPHA-CARBOXYAMINOCARBOXYLIC 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) | 1953-07-24 | 1954-01-23 | 1954-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-07-24 | 1958-01-23 | 1958-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-07-24 | 1962-01-23 | 1962-07-25 | $7700.00 | Window Closed / Lapsed |