US3897424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for 7-{62 -amino-7-{60 -methoxy-cephalosporanic acid esters and related compounds
Assignee: Eli Lilly and Co
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Filing: 1973-07-23
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Granted: 1975-07-29
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Expires: 1993-07-23
Abstract
Abstract WHEREIN Z is H or an organic radical, eg. acetoxy, methoxy, carbamoyloxy or 5-thio-1-methyltetrazol; comprising low temperature 7-methoxylation of a 7-(p-nitrobenzyloxycarbamido) cephalosporin ester; reduction of the methoxylation product to an intermediate reduction product; and treatment of the reduction product with silica gel. Methoxy amine nucleus esters are valuable intermediates for synthesis of antibiotics. Process for preparing 7- Beta -Amino-7- Alpha methoxycephalosporin esters
Inventors
- 👤 Gary A Koppel
- 👤 William H W Lunn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:56
CPC Classifications
C; C07; C07D; C07D501/00; C07D501/14; C07D501/16; C07D501/18; C07D501/20; C07D501/57
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
10 words
THE METHOOD FO PREPARING A 7B-AMINO-7A-METHOXY-3CEPHEM ESTER OF THE FORMULA
Claim 2
Dependent Claim
10 words
THE METHOOD FO PREPARING A 7B-AMINO-7A-METHOXY-3CEPHEM ESTER OF THE FORMULA
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein Z is hydrogen, acetoxy or methoxy and R is diphenylmethyl.
Claim 4
Dependent Claim
8 words
The method of claim 1 wherein Z is
Claim 5
Dependent Claim
8 words
The method of claim 1 wherein Z is
Claim 6
Dependent Claim
24 words
The method of Claim 2 wherein the 7 Beta -(p-nitrobenzyloxycarbamido)-7 Alpha -methoxy-3-cephem ester is reduced with hydrogen in the presence of a palladium catalyst.
Claim 7
Dependent Claim
18 words
The method of claim 3 wherein the 7 Beta -(p-nitrobenzyloxycarbamido)-7 Alpha -methoxy-3-cephem ester is reduced with sodium dithionate.
Claim 8
Dependent Claim
22 words
The method of claim 1 wherein the methoxy 3-cephem ester reduction product is commingled with silica gel in an inert liquid medium.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |