Patent US3852297A successfully refreshed from Google Patents.
Patent US3769280A successfully refreshed from Google Patents.
US3769280A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for acylation of cephalosporin esters
Assignee: Lilly Industries Ltd
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Filing: 1971-09-24
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Granted: 1973-10-30
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Expires: 1991-09-24
Abstract
Abstract ACRYLATION OF THE P-NOTROBENZYL ESTER OF 7-AMINOCEPHALOSPORANIC ACID OR 7-AMINODESACETOXYCEPHALOSPORANIC ACID WITH A MIXED ANHYDRIDE IS IMPROVED WHEN CARRIED OUT AT A TEMPERATURE BETWEEN BELOW ABOUT -15*C. AND ABOUT -50*C.
Inventors
- 👤 G Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:55
CPC Classifications
C; C07; C07D; C07D501/00; C07D501/02; C07D501/04; C07D501/06
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) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |