5-halo-tryptamine derivatives used as ligands on the 5-HT

1. A method of selectively interacting with the 5-HT- 6 and/or 5-HT 7 serotonin receptors comprising administering to a subject in need thereof an effective amount of a compound of Formula (I)

wherein:

R 1 and R 2 , the same or different, are H or C 1 –C 6 linear or branched alkyl;

R 3 =C 1 –C 6 linear or branched alkyl;

R 4 =halogen; and of the pharmaceutically acceptable salts thereof.

2. The method according to claim 1 , wherein said selective interaction treats nervous system pathologies associated with serotonin level deficit, systemic pathologies involving the cardiovascular system, and systemic pathologies involving the gastrointestinal tract.

3. The method, according to claim 2 , wherein hypertension is treated.

4. The method according to claim 2 , wherein irritable bowel disease is treated.

5. The method according to claim 1 , wherein the method treats migraine, depression, hypertension, psychosis and symptoms arising from the desynchronisation and/or loss of circadian rhythms.

6. The method according to claim 1 , wherein ligands of the 5-HT 6 serotoninergic receptor and are used in the treatment of depression, mood disorders, psychosis, schizophrenia, motor disorders, cognitive disorders, Parkinson's disease, Alzheimer's disease, or Huntington's disease.

7. The method according to claim 1 , wherein in the compound of Formula (I) R 1 is the same as to R 2 .

8. The according to claim 1 , wherein in the compound of Formula (I), R 3 is methyl and R 4 is bromo or chloro.

9. The method according to claim 1 , wherein in the compound of Formula (I) R 4 is bromo.

10. The method according to claim 9 , wherein the compound is 5-bromo-2-methyl-N,N-dimethyltryptamine.

11. The method according to claim 1 , wherein the compound R 4 is chloro.

12. The method according to claim 11 , wherein the Formula (I) compound is 5-chloro-2-methyl-N,N-dimethyltryptamine or 5-chloro-2-ethyl-N,N-dimethyltryptamine.

13. The method according to claim 9 , wherein the compounds are ligands of the 5-HT 7 serotoninergic receptor.

14. The method according to claim 11 , wherein the compounds are ligands of the 5-HT 6 serotoninergic receptor.

15. The method according to claim 13 wherein the method treats depression, migraine, hypertension, assists or improves the individual learning processes or counteracts the desynchronisation of human biological rhythms giving rise to mental fatigue, depression and sleep disorders.

16. The method according to claim 14 wherein the method treats depression, mood disorders, psychosis, schizophrenia, motor disorders, cognitive disorders, Parkinson's disease, Alzheimer's disease, or Huntington's disease.

17. A compound of the formula

wherein:

R 1 and R 2 , the same or different, are H or C 1 –C 6 alkyl;

R 3 =C 1 –C 6 alkyl;

R 4 =halogen, or a pharmaceutically acceptable salt thereof, with the proviso that when R 4 is fluoro, chloro or bromo, R 3 is methyl, R 1 and R 2 , either the same or different, are not H or methyl.

18. A process for the preparation of the compounds according to claim 17 , according to the following scheme:

said process comprsing:

a) reacting 5-halo-2-alkyl-indole (1) with 1-dimethylamino-2-nitroethylene in trifluoroacetic acid to give compound (2):

b) subjecting compound (2) to reduction of the ethyl double bond adjacent to the nitro group, to give the corresponding saturated derivative (3); and

c) carrying out functionalisation of the primary amino group in compound (3) with the groups given in the definitions for R 1 and R 3 .

19. A pharmaceutical compositions comprising at least one compound of claim 17 as the active ingredient, admixed with a pharmaceutically acceptable vehicles and/or excipient.