Patent US3878345A successfully refreshed from Google Patents.
US4282148A
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Synthesis of thienamycin via esters of (3SR, 4RS)-3-[(SR)-1-hydroxyethyl]-β,2-dioxo-4-azetidinebutanoic acid
Assignee: Merck and Co Inc
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Filing: 1980-01-14
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Granted: 1981-08-04
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Expires: 2000-01-14
Abstract
Abstract Disclosed is a process for the stereocontrolled total synthesis of thienamycin, which synthesis proceeds via intermediate II: <IMAGE> II wherein R3 is a readily removable carboxyl protecting group.
Inventors
- 👤 Thomas M. H. Liu
- 👤 David G. Melillo
- 👤 Kenneth M. Ryan
- 👤 Ichiro Shinkai
- 👤 Meyer Sletzinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:12
CPC Classifications
C; C07; C07D; C07D309/00; C07D309/16; C07D309/28; C07D309/30; C07D205/00; C07D205/02; C07D205/06; C07D205/08; C07D477/00; C07D477/02; C07D477/04; C07D477/10; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
29 words
A compound having the structural formula: ##STR21## wherein R 3 is hydrogen or a readily removable protecting group selected from p-nitrobenzyl, o-nitrobenzyl, benzyl, phenyl, methyl, ethyl, t-butyl, or 1,1,1-trichloroethyl.
Claim 2
Dependent Claim
29 words
A compound having the structural formula: ##STR21## wherein R 3 is hydrogen or a readily removable protecting group selected from p-nitrobenzyl, o-nitrobenzyl, benzyl, phenyl, methyl, ethyl, t-butyl, or 1,1,1-trichloroethyl.
Claim 3
Dependent Claim
44 words
A compound having the structural formula: ##STR22## wherein R 8 is a readily removable acyl group selected from formyl, acetyl, and benzoyl and R 3 is hydrogen or a readily removable protecting group selected from p-nitrobenzyl, o-nitrobenzyl, benzyl, phenyl, methyl, ethyl, t-butyl, or 1,1,1-trichloroethyl.
Claim 4
Dependent Claim
44 words
A compound having the structural formula: ##STR22## wherein R 8 is a readily removable acyl group selected from formyl, acetyl, and benzoyl and R 3 is hydrogen or a readily removable protecting group selected from p-nitrobenzyl, o-nitrobenzyl, benzyl, phenyl, methyl, ethyl, t-butyl, or 1,1,1-trichloroethyl.
References Cited (Backward Citations)
US4217453A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-03 | 1985-02-02 | 1985-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-03 | 1989-02-02 | 1989-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-03 | 1993-02-02 | 1993-08-04 | $7700.00 | Window Closed / Lapsed |