Patent US2050231A successfully refreshed from Google Patents.
Patent US2634265A successfully refreshed from Google Patents.
US2634265A
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Riboflavin derivatives and process of preparing same
Assignee: Vico Products Co
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Filing: 1951-03-30
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Granted: 1953-04-07
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Expires: 1971-03-30
Abstract
No abstract record available.
Inventors
- 👤 Hugh M Millen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:20
CPC Classifications
C; C07; C07D; C07D475/00; C07D475/12; C07D475/14
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
72 words
A WATER-SOLUBLE PRODUCT RESULTING FROM REACTING 1 PART, BY WEIGHT, OF A 9-POLYHYDROXYALKYLISOALLOXAZINE WITH AT LEAST SEVERAL PARTS, BY WEIGHT, OF LACTIC ACID, IN THE SUBSTANTIAL ABSENCE OF WATER, AT A TEMPERATURE BETWEEN ABOUT 140 DEGRESS C. AND ABOUT 190 DEGREES C., AND THEN ESTERIFYING AT LEAST A SUBSTANTIAL PART OF THE FREE ACID CONTENT OF SAID 9-POLYHYDROXYALKYL-ISOALLOXAZINELACTIC ACID REACTION PRODUCT BY REACTING THE SAME WITH A NON-TOXIC WATER-SOLUBLE ALIPHATIC POLYHYDROXY SUBSTANCE.
References Cited (Backward Citations)
US1173317A
Cited
US1701200A
Cited
GB376149A
Cited
US2358356A
Cited
US2407624A
Cited
US2423074A
Cited
US2499003A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-04-06 | 1956-10-06 | 1957-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-04-06 | 1960-10-06 | 1961-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-04-06 | 1964-10-06 | 1965-04-07 | $7700.00 | Window Closed / Lapsed |