US4018783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Esters of metrizoic acid
Assignee: Beecham Group PLC
•
Filing: 1974-07-26
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Granted: 1977-04-19
•
Expires: 1994-07-26
Abstract
Abstract The phthalide, alkyl, aralkyl, dialkylaminoalkyl and alkylcarbonyloxyalkyl esters of iothalamic acid and metrizoic acid are useful as X-ray contrast agents.
Inventors
- 👤 Maurice John Soulal
- 👤 Kenneth Utting
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:57
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/62; C07D213/63; C07D213/68; A; A61; A61K; A61K49/00; A61K49/04; A61K49/0433
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
5 words
Phthalide ester of metrizoic acid.
Claim 2
Dependent Claim
5 words
Phthalide ester of metrizoic acid.
Claim 3
Dependent Claim
2 words
Pivaloyloxymethyl metrizoate.
Claim 4
Dependent Claim
2 words
Pivaloyloxymethyl metrizoate.
Claim 5
Dependent Claim
2 words
α-Pivaloyloxyethyl metrizoate.
Claim 6
Dependent Claim
2 words
α-Pivaloyloxyethyl metrizoate.
References Cited (Backward Citations)
FR878387A
Cited
US2776241A
Cited
GB973881A
Cited
US3409662A
Cited
US3812151A
Cited
US3666800A
Cited
US3795698A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-04-18 | 1980-10-18 | 1981-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-18 | 1984-10-18 | 1985-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-18 | 1988-10-18 | 1989-04-19 | $7700.00 | Window Closed / Lapsed |