Patent US3669978A successfully refreshed from Google Patents.
US3669978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of semi-synthetic penicillin intermediate
Assignee: Wyeth LLC
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Filing: 1970-05-28
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Granted: 1972-06-13
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Expires: 1990-05-28
Abstract
Abstract A novel process for the preparation of an intermediate mixture which is useful in the production of penicillanic acid derivatives is described. The main component of the intermediate mixture is 2-((6-amino-3,3-dimethyl-7-oxo-4-thia-1azabicyclo(3,2,O)hept-2-yl)carbonyl) -1,2-benzisothiazol-3(2H)one-1,1-dioxide hydrochloride.
Inventors
- 👤 Robert P Deist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:47
CPC Classifications
C; C07; C07D; C07D499/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
10 words
A process according to claim 1 wherein R is benzyl.
Claim 2
Dependent Claim
10 words
A process according to claim 1 wherein R is phenoxymethyl.
Claim 3
Dependent Claim
12 words
A process according to claim 1 wherein the (lower) alkanol is methanol.
Claim 4
Dependent Claim
20 words
A process according to claim 1 wherein the reaction conducted at a temperature of about 15* to about 30* C.
Claim 5
Dependent Claim
12 words
A process according to claim 1 wherein the acid acceptor is N,N-dimethylaniline.
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) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |