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US4376864A
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US
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Cyclic acetals of glutamic acid-γ-semialdehyde, process for their production and use
Assignee: Evonik Operations GmbH
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Filing: 1981-11-10
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Granted: 1983-03-15
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Expires: 2001-11-10
Abstract
Abstract The invention is directed to cyclic acetals of glutamic acid-γ-semialdehyde of the formula ##STR1## in which A is an unsubstituted alkylene group having 2 to 3 carbon atoms or such an alkylene group substituted by 1 to 2 methyl groups and to a method of producing a compound of formula (I) by reaction of a compound of the general formula ##STR2## in which A is as defined above with hydrogen cyanide or a cyanide ion supplying compound, ammonia or an ammonium ion supplying compound and carbon dioxide or a carbonate ion supplying compound and basic hydrolysis of the reaction mixture obtained and to using the compound of formula (I) to produce D,L-proline.
Inventors
- 👤 Karlheinz Drauz
- 👤 Axel Kleemann
- 👤 Marc Samson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:54
CPC Classifications
C; C07; C07D; C07D207/00; C07D207/02; C07D207/04; C07D207/10; C07D207/16; C07D317/00; C07D317/08; C07D317/10; C07D317/14; C07D317/30; C07D319/00; C07D319/04; C07D319/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
35 words
A cyclic acetal of glutamic acid-γ-semialdehyde of the formula ##STR9## in which A is an alkylene group with 2 to 3 carbon atoms or such an alkylene group substituted by 1 to 2 methyl groups.
Claim 2
Dependent Claim
35 words
A cyclic acetal of glutamic acid-γ-semialdehyde of the formula ##STR9## in which A is an alkylene group with 2 to 3 carbon atoms or such an alkylene group substituted by 1 to 2 methyl groups.
References Cited (Backward Citations)
US2500155A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-14 | 1986-09-13 | 1987-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-14 | 1990-09-13 | 1991-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-14 | 1994-09-13 | 1995-03-15 | $7700.00 | Window Closed / Lapsed |