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Patent US2572579A successfully refreshed from Google Patents.
US2572579A
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Disubstituted carbamic acid esters of 3-hydroxy-1-alkyl-pyridinium salts
Assignee: F Hoffmann La Roche AG
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Filing: 1946-05-18
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Granted: 1951-10-23
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Expires: 1966-05-18
Abstract
No abstract record available.
Inventors
- 👤 Urban Rene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:32
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/62; C07D213/63; C07D213/65
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
12 words
SALTS OF N,N-DISUBSTITUTED CARBOMIC ACID ESTERS OF N-ALKYL-3-HYDROXYPYRIDINUM OF THE GENERAL FORMULA:
Claim 2
Dependent Claim
12 words
SALTS OF N,N-DISUBSTITUTED CARBOMIC ACID ESTERS OF N-ALKYL-3-HYDROXYPYRIDINUM OF THE GENERAL FORMULA:
References Cited (Backward Citations)
US2304830A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-10-22 | 1955-04-23 | 1955-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-10-22 | 1959-04-23 | 1959-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-10-22 | 1963-04-23 | 1963-10-23 | $7700.00 | Window Closed / Lapsed |