Patent US4147703A successfully refreshed from Google Patents.
US4147703A
Expired / Lapsed
US
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Process to produce 8-methoxypsoralen
Assignee: Hoffmann La Roche Inc
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Filing: 1978-03-08
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Granted: 1979-04-03
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Expires: 1998-03-08
Abstract
Abstract The invention relates to synthetic processes to produce the known pharmacologically active 9-methoxypsoralen. Also disclosed are various novel intermediates utilized in these processes.
Inventors
- 👤 Arnold A. Liebman
- 👤 Yu-Ying Liu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:49
CPC Classifications
C; C07; C07D; C07D493/00; C07D493/02; C07D493/04; C07D307/00; C07D307/77; C07D307/78; C07D307/86
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
80 words
A process to produce a compound of the formula ##STR4## which comprises (A) reacting a compound of the formula ##STR5## with hydrogen and a Noble metal in acetic acid (B) reacting the product of (A) with a mixture of zinc cyanide and hydrochloric acid; (C) reacting the product of (B) with dichlorodicyanoquinone in an inert solvent; (D) reacting the product of (C) with ethyl cyanoacetate in a polar solvent; (E) decarboxylating the product of (D) to yield the final product.
Claim 2
Dependent Claim
80 words
A process to produce a compound of the formula ##STR4## which comprises (A) reacting a compound of the formula ##STR5## with hydrogen and a Noble metal in acetic acid (B) reacting the product of (A) with a mixture of zinc cyanide and hydrochloric acid; (C) reacting the product of (B) with dichlorodicyanoquinone in an inert solvent; (D) reacting the product of (C) with ethyl cyanoacetate in a polar solvent; (E) decarboxylating the product of (D) to yield the final product.
References Cited (Backward Citations)
US3244729A
Cited
US3201421A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-02 | 1982-10-02 | 1983-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-02 | 1986-10-02 | 1987-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-02 | 1990-10-02 | 1991-04-03 | $7700.00 | Window Closed / Lapsed |