Amino derivatives of pyrido(3,4-b)pyrazine carboxylic acids and esters

• US 4,022,779 A
• Filed: 10/07/1975
• Issued: 05/10/1977
• Est. Priority Date: 07/25/1974
• Status: Expired due to Term

• Current Assignee: E R Squibb & Sons Incorporated
• Original Assignee: E R Squibb & Sons Incorporated
• Inventors: Denzel, Theodor, Hoehn, Hans
• Primary Examiner(s): Rush, Raymond V.
• Assistant Examiner(s): Tovar, Jose
• Application Number:
  US05/620,469
• Time in Patent Office: 581 Days
• Field of Search: 260/250 BC, 260/268 BC, 260/256.4 H, 260/250 A, 260/250 AH
• US Class Current: 544/350
• CPC Class Codes: C07D 213/80 in position 3

Abstract

New derivatives of pyrido[3,4-b]pyridine carboxylic acids and esters and their acid addition salts have the general formula ##STR1## They are useful as anti-inflammatory agents and central nervous system depressants.

Claims

1. A compound of the formula ##STR36## wherein R, R₃, R₄ and R₅ each is hydrogen or lower alkyl;

R₁ and R₂ each is hydrogen, lower alkyl, lower alkanoyl, di(lower alkylamino)lower alkyl, phenyl, substituted phenyl, or ##STR37## is an unsubstituted or substituted heterocyclic of the group consisting of pyrrolidino, piperidino, dihydropyrimidinyl, dihydropyridazinyl or piperazino;

wherein the substituted phenyl bears one or two lower alkyl, lower alkoxy, halogen, trifluoromethyl, amino or carboxy groups, and the substituted heterocyclics bear a hydroxy-lower alkyl, one or two lower alkyl or a phenyl group; and

acid addition salts thereof.

2. A compound as in claim 1 wherein R and R₃ each is lower alkyl and R₄ and R₅ each is hydrogen.

3. A compound as in claim 1 wherein R is ethyl, R₃ is methyl and R₄ and R₅ each is hydrogen.

4. A compound as in claim 1 wherein R is hydrogen or lower alkyl of 1 to 4 carbon atoms;

R₁ and R₂ each is hydrogen, lower alkyl of 1 to 4 carbon atoms, or ##STR38## N-(lower alkyl)piperazino;

R₃ is lower alkyl and R₄ and R₅ each is hydrogen or lower alkyl.

5. A compound as in claim 2 wherein ##STR39## is N-(lower alkyl)piperazinyl.

6. A compound as in claim 2 wherein ##STR40## is 4-phenylpiperazinyl.

7. A compound as in claim 2 wherin R₁ is hydrogen and R₂ is lower alkyl.

8. A compound as in claim 2 wherein R₁ is hydrogen and R₂ is di(lower alkylamino)lower alkyl.

9. A compound as in claim 1 wherein R is ethyl, R₄ and R₅ each is hydrogen, ##STR41## is 4-methyl-1-piperazinyl and R₃ is methyl.

10. A compound as in claim 1 wherein R is ethyl, R₄ and R₅ each is hydrogen, ##STR42## is 4-phenyl-l-piperazinyl and R₃ is methyl.

11. A compound as in claim 1 wherein R is ethyl, R₄ and R₅ each is hydrogen, ##STR43## is 4-phenyl-1-piperazinyl and R₃ is methyl.

12. A compound as in claim 1 wherein R is ethyl, R₁, R₄ and R₅ each is hydrogen, R₂ is butyl and R₃ is methyl.

13. A compound as in claim 1 wherein R is ethyl, R₁, R₄ and R₅ each is hydrogen, R₂ is 3-dimethylaminopropyl and R₃ is methyl.

14. A compound as in claim 1 wherein ##STR44## is pyrrolidino.

15. A compound as in claim 1 wherein ##STR45## is piperazino.

16. A compound as in claim 1 wherein ##STR46## is piperidino. is piperidino.

18. A compound as in claim 1 wherein R, R₃, R₄ and R₅ each is hydrogen or lower alkyl;

R₁ and R₂ each is hydrogen, lower alkyl, lower alkanoyl, di(lower alkylamino)lower alkyl, phenyl or substituted phenyl wherein the substituted phenyl bears one or two lower alkyl, lower alkoxy, halogen, trifluoromethyl, amino or carboxy groups, and acid addition salts thereof.

17. A compound of the formula ##STR47## wherein R, R₃, R₄ and R₅ each is hydrogen or lower alkyl;

R₁ and R₂ each is hydrogen, lower alkyl, lower alkanoyl, di(lower alkylamino)lower alkyl, phenyl, substituted phenyl, or ##STR48## is an unsubstituted or substituted heterocyclic of the group consisting of pyrrolidino, piperidino, dihydropyrimidinyl, dihydropyridazinyl or piperazino;

wherein the substituted phenyl bears one or two lower alkyl, lower alkoxy, halogen, trifluoromethyl, amino or carboxy groups, and the substituted heterocyclics bear a hydroxy-lower alkyl, one to two lower alkyl or a phenyl group.