US2575344A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dihydroxypropyl theophylline
Assignee: STATE OF IOWA
•
Filing: 1946-03-01
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Granted: 1951-11-20
•
Expires: 1966-03-01
Abstract
No abstract record available.
Inventors
- 👤 James W Jones
- 👤 Paul V Maney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:10
CPC Classifications
C; C07; C07D; C07D473/00; C07D473/02; C07D473/04; C07D473/06; C07D473/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
55 words
THE PROCESS OF PREPARING DIHYDROXY-PROPYL THEOPHYLLINE WHICH CONSISTS IN FIRST TREATING AN AQUEOUS SOLUTION OF THEOPHYLLINE WITH A HYDROXIDE CHOSEN FROM THE GROUP CONSISTS OF SODIUM HYDROXIDE AND POTASSIUM HYDROXIDE, TRANSFORMING THE THUS PRODUCED ALKALI METAL COMPOUND OF THEOPHYLLINE TO DIHYDROXYPROPYL THEOPHYLLINE BY TREATMENT WITH 1-CHLORO-2,3 DIHYDROXY PROPANE AT A TEMPERATURE OF SUBSTANTIALLY 110* C.
Claim 2
Dependent Claim
5 words
DIHYDROXYPROPL THEOPHYLLINE HAVING THE FORMULA:
References Cited (Backward Citations)
GB190704250A
Cited
FR569463A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-11-19 | 1955-05-21 | 1955-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-19 | 1959-05-21 | 1959-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-19 | 1963-05-21 | 1963-11-20 | $7700.00 | Window Closed / Lapsed |