Patent US3574718A successfully refreshed from Google Patents.
US3574718A
Expired / Lapsed
US
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Method for producing x-ray contrast agents
Assignee: Pfizer Health AB
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Filing: 1967-12-11
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Granted: 1971-04-13
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Expires: 1987-12-11
Abstract
Abstract IODINE COMPOUNDS OF THE FORMULA; ((2,4,6-TRI(I-),3-(HOOC-)PHENYL)-N(-R))2-A WHEREIN R IS A LOWER ACYL GROUP HAVING NO MORE THAN 5 CARBON ATOMS AND WHEREIN A IS AN ALKYLENE GROUP SUBSTITUTED BY AT LEAST ONE SUBSTITUENT OF THE FORMULA -O-R1 WHEREIN R1 IS A HYDROGEN OR A LOWER ALKYL OR A LOWER ACYL GROUP HAVING NO MORE THAN 5 CARBON ATOMS, SAID ALKYLENE GROUP CONTAINING FROM 3 TO 15 INCLUSIVE CARBON ATOMS AND BEING OPTIONALLY BROKEN BY ONE OR MORE OXYGEN BRIDGES; OR PHYSIOLOGICALLY ACCEPTABLE SALTS THEREOF; AND THEIR METHOD OF PREPARATION ARE PROVIDED. THESE COMPOUNDS ARE ESPECIALLY USEFUL AS X-RAY CONTRAST AGENTS.
Inventors
- 👤 Lars Bjork
- 👤 Uno E Erikson
- 👤 Bjorn G-A Ingelman
- 👤 Bernt J Lindberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:05
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/04; A61K49/0433; A61K49/0447; A61K49/0452
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) | 1974-04-12 | 1974-10-12 | 1975-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-12 | 1978-10-12 | 1979-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-12 | 1982-10-12 | 1983-04-13 | $7700.00 | Window Closed / Lapsed |