US2490392A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydropyranyl-oxazines, thiazines, oxazolidines, and thiazolidines and their preparation
Assignee: Shell Development Co
•
Filing: 1948-01-12
•
Granted: 1949-12-06
•
Expires: 1968-01-12
Abstract
No abstract record available.
Inventors
- 👤 Richard R Whetstone
- 👤 Seaver A Ballard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:29
CPC Classifications
C; C07; C07D; C07D413/00; C07D413/02; C07D413/04
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2243295A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-05 | 1953-06-06 | 1953-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-05 | 1957-06-06 | 1957-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-05 | 1961-06-06 | 1961-12-06 | $7700.00 | Window Closed / Lapsed |