US4136101A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing dialkyl (p-aminobenzoyl) glutamates
Assignee: Wyeth Holdings LLC
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Filing: 1978-02-03
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Granted: 1979-01-23
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Expires: 1998-02-03
Abstract
Abstract A process for the preparation of dialkyl (p-aminobenzoyl) glutamates is disclosed. Dialkyl (p-Aminobenzoyl) glutamates are useful as intermediates in the synthesis of N-{p-([(2,4-diamino-6-pteridinyl)-methyl]methylamino)benzoyl} glutamic acid, also known as 4-amino-N 10 -methylpteroylglutamic acid. The compound zinc N-(p-methylaminobenzoyl)-L-(+)-glutamate, is also disclosed.
Inventors
- 👤 John Kazan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:53
CPC Classifications
C; C07; C07C; C07C237/00; C07C237/28; C07C237/36; C07C2601/00; C07C2601/12; C07C2601/14
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
109 words
A process for the preparation of an ester represented by formula (I): ##STR3## wherein R 1 is hydrogen or C 1 -C 4 alkyl and R 2 is C 1 -C 4 alkyl, which comprises reacting a zinc salt of an acid represented by formula (II): ##STR4## wherein R 1 is as previously identified, with a C 1 -C 4 alcohol at ambient temperature in the presence of an inorganic acid to form said ester of formula (I); diluting the reaction mixture with water; clarifying the diluted reaction mixture; alkalizing said clarified reaction mixture to about pH 4-6 to precipitate said ester of formula (I); and, recovering the same.
Claim 2
Dependent Claim
109 words
A process for the preparation of an ester represented by formula (I): ##STR3## wherein R 1 is hydrogen or C 1 -C 4 alkyl and R 2 is C 1 -C 4 alkyl, which comprises reacting a zinc salt of an acid represented by formula (II): ##STR4## wherein R 1 is as previously identified, with a C 1 -C 4 alcohol at ambient temperature in the presence of an inorganic acid to form said ester of formula (I); diluting the reaction mixture with water; clarifying the diluted reaction mixture; alkalizing said clarified reaction mixture to about pH 4-6 to precipitate said ester of formula (I); and, recovering the same.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein the alkalizing agent is ammonium hydroxide and the clarified reaction mixture is adjusted to about pH 5.
Claim 4
Dependent Claim
10 words
The process of claim 2 wherein the alcohol is ethanol.
Claim 5
Dependent Claim
11 words
The process of claim 1 wherein the salt is zinc N-(p-methylaminobenzoyl)glutamate.
Claim 6
Dependent Claim
11 words
The process of claim 4 wherein the salt is zinc N-(p-methylaminobenzoyl)-L-(+)-glutamate.
Claim 7
Dependent Claim
4 words
The compound zinc N-(p-methylaminobenzoyl)-L-(+)-glutamate.
Claim 8
Dependent Claim
4 words
The compound zinc N-(p-methylaminobenzoyl)-L-(+)-glutamate.
References Cited (Backward Citations)
US3892801A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-01-22 | 1982-07-24 | 1983-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-22 | 1986-07-24 | 1987-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-22 | 1990-07-24 | 1991-01-23 | $7700.00 | Window Closed / Lapsed |