Patent US3862181A successfully refreshed from Google Patents.
US3862181A
Expired / Lapsed
US
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Process for preparing cephalosporins
Assignee: ER Squibb and Sons LLC
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Filing: 1971-07-08
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Granted: 1975-01-21
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Expires: 1991-07-08
Abstract
Abstract Compounds containing a cephem nucleus are prepared by heating a 1-oxide of a Schiff base of 6-aminopenicillanic acid. These cephem compounds are useful as intermediates in the preparation of physiologically active cephalosporins.
Inventors
- 👤 D Barry Davis
- 👤 Ekkehard Bohme
- 👤 Joseph Edward Dolfini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:33
CPC Classifications
C; C07; C07D; C07D499/00; C07D499/21; C07D499/42
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
16 words
The process of claim 1 wherein the 6-aminopenicillanic acid is in the form of its ester.
Claim 2
Dependent Claim
18 words
The process of claim 2 wherein the Schiff base is the 1-oxide of an ester of 6-benzylideneaminopenicillanic acid.
Claim 3
Dependent Claim
19 words
The process of claim 2 wherein the Schiff base is the trichloroethyl ester of the 1oxide of 6-benzylideneaminopenicillanic acid.
Claim 4
Dependent Claim
18 words
The process of claim 2 wherein the Schiff base is the 1-oxide of an ester of 6-salicylideneaminopenicillanic acid.
Claim 5
Dependent Claim
19 words
The process of claim 2 wherein the Schiff base is the trichloroethyl ester of the 1-oxide of 6-salicylideneaminopenicillanic acid.
Claim 6
Dependent Claim
17 words
The process of claim 3 wherein the Schiff base is the p-methoxybenzyl ester of the 1-oxide of
Claim 7
Dependent Claim
5 words
A compound of the formula:
Claim 8
Dependent Claim
15 words
The compound of claim 8 wherein R is phenyl and R'''' is an esterifying group.
Claim 9
Dependent Claim
15 words
The compound of claim 8 wherein R is o-hydroxyphenyl and R'''' is an esterifying group.
Claim 10
Dependent Claim
9 words
the compound of claim 10 wherein R'''' is p-methoxybenzyl.
Claim 11
Dependent Claim
5 words
A compound of the formula
Claim 12
Dependent Claim
9 words
The compound of claim 12, wherein R is phenyl.
Claim 13
Dependent Claim
9 words
The compound of claim 12, wherein R is o-hydroxyphenyl.
Claim 14
Dependent Claim
5 words
A compound of the formula:
Claim 15
Dependent Claim
5 words
A compound of the formula
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) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |