US3716533A
Expired / Lapsed
US
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N-deformylation of 3-halomethyl-7beta-formamidocephalosporin-1-oxidesn-deformylation of 3-halomethyl-7 beta-formamidocephalosporin-1-oxide
Assignee: Glaxo Laboratories Ltd
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Filing: 1970-08-21
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Granted: 1973-02-13
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Expires: 1990-08-21
Abstract
Abstract A PROCESS FOR THE PREPARATION OF 7B-AMINOCEPHEM-4CARBOXYLIC ACIDS AND DERIVATIVES THEREOF COMPRISES N-DEFORMYLATING A 7B-FORMAMIDOCEPHEM-4-CARBOXYLIC ACID OR DERIVATIVE THEREOF WITH A LEWIS ACID A LOWER ALKANE DIOL UNDER SUBSTANTIALLY ANHYDROUS CONDITIONS.
Inventors
- 👤 D Humber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:29
CPC Classifications
C; C07; C07D; C07D501/00; C07D501/14; C07D501/16; C07D501/18
Claims Analysis
Total Claims: 0
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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) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |