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US3818037A
Expired / Lapsed
US
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3-methylene-6-nitro-n-substituted isoindolones-(1)
Assignee: BASF SE
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Filing: 1971-11-08
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Granted: 1974-06-18
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Expires: 1991-11-08
Abstract
Abstract 3-METHYLENE-6-NITRO-N-substituted isoindolones-(1) produced by reacting 6-nitro-N-substituted isoindolones-(1) with formaldehyde or an agent yielding formaldehyde. The new compounds are starting materials for the production of dyes.
Inventors
- 👤 E Schefczik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:53
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/44; C07D209/46
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3224999A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |