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US2909520A
Expired / Lapsed
US
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Process for making acylated
Assignee: —
•
Filing: —
•
Granted: 1959-10-20
•
Expires: 1976-10-20
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:12
CPC Classifications
C; C07; C07D; C07D279/00; C07D279/10; C07D279/14; C07D279/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
53 words
A PROCESS FOR THE PREPARATION OF ACYLATED LWUCOMETHYLENE BLUE WHICH COMPRISES INTRODUCING AN ACYL GROUPING IN THE NITROGEN ATOM OF THE LEUCOMETHYLENE BLUE BY REACTING SAID LEUCOMETHYLENE BLUE WITH A CARBOCYCLIC AROMATIC CARBOXYLIC ACYLATING AGENT IN AN AQUEOUS MEDIUM AND IN THE PRESENCE OF A WATER-IMMIXSCIBLE SOLVENT AT A PH BELOW ABOUT 6.
Claim 2
Dependent Claim
53 words
A PROCESS FOR THE PREPARATION OF ACYLATED LWUCOMETHYLENE BLUE WHICH COMPRISES INTRODUCING AN ACYL GROUPING IN THE NITROGEN ATOM OF THE LEUCOMETHYLENE BLUE BY REACTING SAID LEUCOMETHYLENE BLUE WITH A CARBOCYCLIC AROMATIC CARBOXYLIC ACYLATING AGENT IN AN AQUEOUS MEDIUM AND IN THE PRESENCE OF A WATER-IMMIXSCIBLE SOLVENT AT A PH BELOW ABOUT 6.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-10-19 | 1963-04-20 | 1963-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-10-19 | 1967-04-20 | 1967-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-10-19 | 1971-04-20 | 1971-10-20 | $7700.00 | Window Closed / Lapsed |