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US3836533A
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US
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10-hydroxy-2-phenyl-5h-pyrido(1,2-a)pyrimido(4,5-d)-pyrimidin-5-one and processes thereto
Assignee: Wyeth LLC
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Filing: 1972-10-30
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Granted: 1974-09-17
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Expires: 1992-10-30
Abstract
Abstract 10 - HYDROXY - 2 - PHENYL - 5H-PYRIDO(1,2-A)PYRIMIDO(4,5-D)PYRIMIDIN-5-ONE AND THE ALKONOYL ESTER THEREOF ARE PREPARED BY THERMAL CYCLIZATION OF A 4-(2-AMINO3-PYRIDYLOXY) - 2 - PHENYL - 5 - PYRIMIDINECARBOXYLIC ACID, ALKYL ESTER OR OF 4-((3-HYDROXY-2 - PYRIDYL)AMINO) - 2 PHENYL-5-PYRIMIDINECARBOXYLIC ACID, OR THE ESTER THEREOF.
Inventors
- 👤 D Kim
- 👤 A Santilli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:33
CPC Classifications
C; C07; C07D; C07D471/00; C07D471/12; C07D471/14
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) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |