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US4473571A
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8-Substituted-2-(4-pyridinyl)-9H-purin-6-amines and their cardiotonic use
Assignee: STWB Inc
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Filing: 1983-01-17
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Granted: 1984-09-25
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Expires: 2003-01-17
Abstract
Abstract 8-Q-2-PY-9H-purin-6-amines (II), salts thereof, their preparation and cardiotonic use are shown, where PY is 4-pyridinyl or 4-pyridinyl having one or two lower-alkyl substituents, and Q is methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, methylthio and ethylthio. Also shown as intermediates for the compounds where Q is methylthio or ethylthio are the corresponding 6-amino-2-PY-9H-purin-8-thiols.
Inventors
- 👤 George Y. Lesher
- 👤 Baldev Singh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:18
CPC Classifications
C; C07; C07D; C07D401/00; C07D401/02; C07D401/04; C07D473/00; C07D473/26; C07D473/32; C07D473/34
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
32 words
8-Q-2-PY-9H-purin-6-amine having the formula ##STR3## where Q is methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, mercapto, methylthio or ethylthio, and Py is 4-pyridinyl or 4-pyridinyl having one or two lower-alkyl substituents, or acid-addition salt thereof.
Claim 2
Dependent Claim
32 words
8-Q-2-PY-9H-purin-6-amine having the formula ##STR3## where Q is methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, mercapto, methylthio or ethylthio, and Py is 4-pyridinyl or 4-pyridinyl having one or two lower-alkyl substituents, or acid-addition salt thereof.
Claim 3
Dependent Claim
17 words
A compound according to claim 1 where Py is 4-pyridinyl, and Q is 1-methylethyl, methyl or ethylthio.
Claim 4
Dependent Claim
5 words
8-(1-Methylethyl)-2-(4-pyridinyl)-9H-purin-6-amine according to claim 1.
Claim 5
Dependent Claim
5 words
8-Methyl-2-(4-pyridinyl)-9H-purin-6-amine according to claim 1.
Claim 6
Dependent Claim
5 words
8-Ethylthio-2-(4-pyridinyl)-9H-purin-6-amine according to claim 1.
Claim 7
Dependent Claim
59 words
A cardiotonic composition for increasing cardiac contractility, said composition comprising a pharmaceutically acceptable inert carrier and, as the active component thereof, a cardiotonically effective amount of the 8-Q-2-PY-9H-purin-6-amine of claim 1 or pharmaceutically acceptable acid-addition salt thereof, where PY is 4-pyridinyl or 4-pyridinyl having one or two lower-alkyl substituents, and Q is methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, methylthio or ethylthio.
Claim 8
Dependent Claim
17 words
A composition according to claim 6 where PY is 4-pyridinyl and Q is 1-methylethyl, methyl or ethylthio.
Claim 9
Dependent Claim
28 words
The method for increasing cardiac contractility in a patient requiring such treatment which comprises administering to such patient a cardiotonically effective amount of the composition of claim 6.
References Cited (Backward Citations)
US3041340A
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 |