Patent US4473502A successfully refreshed from Google Patents.
US4473502A
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Synthesis of thienamycin via (3SR, 4RS)-3-[1 (SR)-hydroxyethyl]-2-oxo-4-azetidineacetic acid
Assignee: Merck and Co Inc
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Filing: 1982-06-07
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Granted: 1984-09-25
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Expires: 2002-06-07
Abstract
Abstract Disclosed is a process for the stereocontrolled total synthesis of thienamycin via intermediates II and IIa: wherein R 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
2026-11-09 19:27
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; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
26 words
A compound having the structural formula ##STR23## wherein R 1 is hydrogen or a removable protecting group selected from benzyl, β,β,β-trichloroethyl, methyl, ethyl, phenyl and t-butyl.
Claim 2
Dependent Claim
26 words
A compound having the structural formula ##STR23## wherein R 1 is hydrogen or a removable protecting group selected from benzyl, β,β,β-trichloroethyl, methyl, ethyl, phenyl and t-butyl.
References Cited (Backward Citations)
US4282148A
Cited
US4287123A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-25 | 1988-03-26 | 1988-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-25 | 1992-03-26 | 1992-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-25 | 1996-03-26 | 1996-09-25 | $7700.00 | Window Closed / Lapsed |