Patent US3979383A successfully refreshed from Google Patents.
US3979383A
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Purification process for 7-aminocephalosporins
Assignee: Eli Lilly and Co
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Filing: 1975-03-07
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Granted: 1976-09-07
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Expires: 1995-03-07
Abstract
Abstract Cephalosporin nucleus compounds represented by the formula: ##SPC1## Wherein R is for example, acetoxy or a 1-(lower alkyl)-1H-tetrazole-5-yl, a 5-(lower alkyl)-1,3,4-thiadiazole-2-yl or a 5-(lower alkyl)-1,3,4-oxadiazole-2-yl group are purified via chromatography over the hydrophilic polyacrylic matrixed quaternary ammonium anionic exchange resin, Amberlite IRA-458.
Inventors
- 👤 Gene M. Wild
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:36
CPC Classifications
C; C07; C07D; C07D501/00; C07D501/14; C07D501/16; C07D501/18; C07D501/02; C07D501/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
97 words
The process for purifying a cephalosporin nucleus compound of the formula ##SPC4## wherein R is a heterocyclic ring selected from the group consisting of ##SPC5## wherein R' is C 1 -C 4 alkyl, which comprises adsorbing said nucleus from an aqueous solution thereof at a pH between 6.5 and 8.5 on the polyacrylic quaternary methylammoniun anion exchange resin Amberlite IRA 458; eluting said resin with phosphate buffer at a pH between 7.5 and 9.0 acidifying the eluate to a pH of between 3.5 and 5.5; and separating said nucleus in a purified form from said acidified eluate.
Claim 2
Dependent Claim
97 words
The process for purifying a cephalosporin nucleus compound of the formula ##SPC4## wherein R is a heterocyclic ring selected from the group consisting of ##SPC5## wherein R' is C 1 -C 4 alkyl, which comprises adsorbing said nucleus from an aqueous solution thereof at a pH between 6.5 and 8.5 on the polyacrylic quaternary methylammoniun anion exchange resin Amberlite IRA 458; eluting said resin with phosphate buffer at a pH between 7.5 and 9.0 acidifying the eluate to a pH of between 3.5 and 5.5; and separating said nucleus in a purified form from said acidified eluate.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein the resin is in the acetate or chloride cycle.
Claim 4
Dependent Claim
18 words
The process of claim 1 wherein the resin is elated with 0.2-0.5 molar potassium phosphate buffer pH 8.
Claim 5
Dependent Claim
11 words
The process of claim 1 wherein R is the 5-methyl-1,3,4-thiadiazole-2-thio group.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein R is the 1-methyl-1H-tetrazole-5-thio group.
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) | 1979-09-07 | 1980-03-08 | 1980-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-07 | 1984-03-08 | 1984-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-07 | 1988-03-08 | 1988-09-07 | $7700.00 | Window Closed / Lapsed |