Patent US4923985A successfully refreshed from Google Patents.
US4923985A
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Process for synthesizing macrocyclic chelates
Assignee: United States Department of Health and Human Services
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Filing: 1988-05-25
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Granted: 1990-05-08
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Expires: 2008-05-25
Abstract
Abstract A process for synthesizing a 12 membered ring tetraaza macromolecule comprising. The process involves condensing an amide of ethylene diamine having a general formula A: ##STR1## wherein n is an integer from 1 to 5 and w is a member selected from the group consisting of --NO 2 , --NH 2 , --NCS, --COOH, --OCH 2 OOCH 3 , --NCOCH 2 --Z with Z being a member selected from the group consisting of Br and I with a nitrogen blocked active ester of a general formula B: ##STR2## wherein PG is an amino protecting group and E is a leaving group.
Inventors
- 👤 Otto A. Gansow
- 👤 Krishan Kumar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:42
CPC Classifications
C; C07; C07D; C07D257/00; C07D257/02; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
87 words
A method of producing a compound of the formula: ##STR21## comprising the steps of: (1) reacting, in dilute anhydrous solution, a compound of the formula: ##STR22## wherein n is an integer from 1 to 5, w is a member selected from the group consisting of --NO 2 , --COOH, --OCH 2 OOCH 3 , with a compound of the formula: ##STR23## wherein PG is a carbamate amino protecting group and E is a leaving group; and (2) extracting the compound of formula I from the reaction mixture.
Claim 2
Independent Claim
87 words
A method of producing a compound of the formula: ##STR21## comprising the steps of: (1) reacting, in dilute anhydrous solution, a compound of the formula: ##STR22## wherein n is an integer from 1 to 5, w is a member selected from the group consisting of --NO 2 , --COOH, --OCH 2 OOCH 3 , with a compound of the formula: ##STR23## wherein PG is a carbamate amino protecting group and E is a leaving group; and (2) extracting the compound of formula I from the reaction mixture.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein said protecting group is an alkyl or aryl substituted carbamate.
Claim 4
Dependent Claim
21 words
The process of claim 1 wherein said leaving group is a hydroxylamine derivative, a substituted phenol derivative, or a mixed anhydride.
Claim 5
Dependent Claim
55 words
A method of claim 1 wherein the extraction of step (2) is accomplished by: (1) drying the reaction mixture from step (1) of claim 1 and (2) extracting the compound of formula (VII) using a biphasic mixture of water and an organic solvent, wherein the compound of formula (VII) is dissolved in the organic solvent.
Claim 6
Dependent Claim
22 words
A method of claim 1 wherein, additionally, the compound of formula VII is reduced to provide a compound of the formula: ##STR24##
Claim 7
Dependent Claim
62 words
A method of claim 5 wherein the reduction is accomplished by the steps of: (1) dissolving the compound of formula VII in trifluoroacetic acid and allowing the resulting mixture to react for about three hours; (2) evaporating the resulting reaction mixture; (3) Precipitating the product in ethyl acetate; and (4) Reducing the product obtained in step (3) with BH 3 in THF.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-07 | 1993-11-06 | 1994-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-07 | 1997-11-06 | 1998-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-07 | 2001-11-06 | 2002-05-08 | $7700.00 | Window Closed / Lapsed |