US3516997A
Expired / Lapsed
US
⏱️ 0.0 years remaining
3,7-disubstituted cephalosporin compounds and preparation thereof
Assignee: Astellas Pharma Inc
•
Filing: 1968-04-12
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Granted: 1970-06-23
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Expires: 1988-04-12
Abstract
No abstract record available.
Inventors
- 👤 Tadayoshi Takano
- 👤 Masaru Kurita
- 👤 Hiroo Nikaido
- 👤 Masashi Mera
- 👤 Nobukiyo Konishi
- 👤 Ritsuko Nakagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:05
CPC Classifications
C; C07; C07D; C07D501/00; C07D501/14; C07D501/16; C07D501/20; C07D501/24; C07D501/36; A; A47; A47L; A47L13/00; A47L13/02; A47L13/04
Claims Analysis
Total Claims: 0
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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) | 1973-06-22 | 1973-12-22 | 1974-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-22 | 1977-12-22 | 1978-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-22 | 1981-12-22 | 1982-06-23 | $7700.00 | Window Closed / Lapsed |