Patent US2838519A successfully refreshed from Google Patents.
US2838519A
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Process for the conversion of stereoisomers
Assignee: CIBA PHARM PROD Inc
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Filing: 1954-12-21
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Granted: 1958-06-10
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Expires: 1974-12-21
Abstract
No abstract record available.
Inventors
- 👤 Rometsch Rudolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:20
CPC Classifications
C; C07; C07D; C07D211/00; C07D211/02; C07D211/04; C07D211/06; C07D211/08; C07D211/18; C07D211/34
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
68 words
A PROCESS FOR THE CONVERSION OF STEREOISOMERS, WHEREIN A MATERIAL COMPRISING THE A-STEREOISOMERIC FORM OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF APHENYL-A-PIPERIDYL-(2)-ACETIC ACIDS, THEIR LOWER ALKYL ESTERS AND AMIDES IS TREATED WITH A STRONG ALKALINE AGENT AT AN ELEVATED TEMPERATURE TO PRODUCE THE B-STEREOISOMERIC FORM, AND IN OPTIONAL SEQUENCE ISOLATING THE B-STEREOISOMERIC FORM FROM THE REACTION PRODUCTS AND ESTERIFYING THE ISOLATED PRODUCT WITH A LOWER ALKANOL.
Claim 2
Dependent Claim
68 words
A PROCESS FOR THE CONVERSION OF STEREOISOMERS, WHEREIN A MATERIAL COMPRISING THE A-STEREOISOMERIC FORM OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF APHENYL-A-PIPERIDYL-(2)-ACETIC ACIDS, THEIR LOWER ALKYL ESTERS AND AMIDES IS TREATED WITH A STRONG ALKALINE AGENT AT AN ELEVATED TEMPERATURE TO PRODUCE THE B-STEREOISOMERIC FORM, AND IN OPTIONAL SEQUENCE ISOLATING THE B-STEREOISOMERIC FORM FROM THE REACTION PRODUCTS AND ESTERIFYING THE ISOLATED PRODUCT WITH A LOWER ALKANOL.
Claim 3
Dependent Claim
14 words
THE B-RACEMATE FORM OF A-PHENYL-A-PIPERIDYL-(2)ACETIC ACID LOWER ALKYL ESTERS FREE FROM THE A-RACEMATE FORM.
Claim 4
Dependent Claim
14 words
THE B-RACEMATE FORM OF A-PHENYL-A-PIPERIDYL-(2)ACETIC ACID LOWER ALKYL ESTERS FREE FROM THE A-RACEMATE FORM.
References Cited (Backward Citations)
US2507631A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-09 | 1961-12-09 | 1962-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-09 | 1965-12-09 | 1966-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-09 | 1969-12-09 | 1970-06-10 | $7700.00 | Window Closed / Lapsed |