ES2514093B1 - NEELOGENIC COMPOUNDS BASED ON MELATONIN AND ITS USE IN THE TREATMENT OF NERVOUS SYSTEM DISEASES - Google Patents

Abstract

Neurogenic compounds based on melatonin and their use in the treatment of diseases of the nervous system. # The present invention, which is included in the field of research and pharmaceutical industry, refers to new chemical entities derived from melatonin with neurogenic properties, modulators of melatonin and / or serotonin receptors, antioxidants and / or cholinergic. It also refers to the procedures for the preparation of these new compounds, the pharmaceutical compositions containing them and their use for the manufacture of a medicament for the treatment of diseases of the nervous system related to neuronal degeneration, depression, psychiatric and cognitive disorders, trauma or cell injury, or other related neurological disorder, treatment of daytime fatigue, sleep disorders, loss of mental efficacy, weakness and irritability and symptoms related to hourly decompensation (jet-lag effect or transoceanic syndrome).

Description

DESCRIPTION

NEELOGENIC COMPOUNDS BASED ON MELATONIN AND ITS USE IN THE TREATMENT OF NERVOUS SYSTEM DISEASES.

 5

SECTOR AND OBJECT OF THE INVENTION

The present invention, which is included in the field of research and pharmaceutical industry, refers to new chemical entities derived from melatonin with neurogenic properties, modulators of melatonin and / or serotonin receptors, antioxidants and / or cholinergic. It also refers to the procedures for the preparation of these new compounds, the pharmaceutical compositions containing them and their use for the manufacture of a medicament for the treatment of diseases of the nervous system related to neuronal degeneration, depression, psychiatric and cognitive disorders. , trauma or cell injury, or other related neurological disorder, treatment of daytime fatigue, sleep disorders, loss of mental efficacy, weakness and irritability and 15 symptoms related to hourly decompensation (jet-lag effect or transoceanic syndrome).

STATE OF THE TECHNIQUE

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Neurogenesis is a vital process in the brains of vertebrates, in which new nerve cells are generated throughout the life of the individual. Although it was thought for a long time that the formation of nerve tissue was restricted to the early stages of embryonic development, this concept changed from 1962 when Altman demonstrated the formation of new neurons in the brain of adult rats (Altman, J. Are new neurons 25 formed in the brains of adult mammals? Science 1962, 135, 1127-1128). In the following years, this same process was found in different vertebrate species, including man (Eriksson, PS; Profileieva, E .; Bjork-Eriksson, T .; Alborn, AM; Nordborg, C .; Peterson, DA; Gage , FH Neurogenesis in the adult human hippocampus. Nat. Med. 1998, 4, 1313-1317). 30

The complete neurogenesis process comprises four main stages: proliferation of stem or progenitor cells, migration to different areas of the central nervous system (CNS), differentiation and maturation in a specific cell type, and integration into neuronal circuits. In the brain of mammals, including man, there are two 35

main deposits of neuronal stem cells: one located in the subgranular zone (SGZ) of the dentate gyrus of the hippocampus and another in the subventricular zone (SVZ) of the lateral ventricles. In these regions, multipotent progenitor neural cells continue to divide giving rise to new functional neurons and glial cells throughout the life of the individual (Decimo, I .; Bifari, F .; Krampera, M .; Fumagalli, G. Neural stem 5 cell niches in health and diseases. Curr. Pharm. Des. 2012, 18, 1755-1783).

Therefore, neurogenic drugs capable of promoting the formation of new neural populations and replacing those damaged by healthy and functionally competent cells, would imply a potential curative treatment for different neurodegenerative diseases and ischemic events, in which cell loss occurs. Nervous (Abdipranoto, A .; Wu, S .; Stayte, S .; Vissel, B. The role of neurogenesis in neurodegenerative diseases and its implications for therapeutic development. CNS Neurol. Disord. Drug Targets 2008, 7, 187-210) .

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So far, numerous biological targets involved in neurogenesis have been discovered, such as serotonin receptors, presenilin 1 (PS1), beta-amyloid precursor protein (APP) and its metabolites, glycogen synthase kinase 3 (GSK-3) and the cholinergic system, among others (Lazarov, O .; Marr, RA Neurogenesis and Alzheimer's disease: at the crossroads. Exp. Neurol. 2010, 223, 267-281). twenty

Regarding the involvement of serotonin receptors in neurogenesis mechanisms, in vitro studies it has been observed that stimulation of 5-HT1A receptors promotes the self-renewal of neuronal precursor cells and that the activation of 5-HT2C receptors favor neuronal proliferation and differentiation (Klempin, F .; Babu, 25 H .; De Pietri Tonelli, D .; Alarcón, E .; Fabel, K .; Kempermann, G. Oppositional effects of serotonin receptors 5- HT1a, 2, and 2c in the regulation of adult hippocampal neurogenesis. Front. Mol. Neurosci. 2010, 3, 14).

In addition, recent studies indicate the involvement of mitochondria in the modulation of neurogenesis, since the excessive increase in the levels of free radicals of oxygen (ROS) and nitric oxide (NO), as well as the increase in pro cytokines Inflammatory inhibits mitochondrial function and proliferation of neuronal stem cells (Voloboueva, LA; Giffard, RG Inflammation, mitochondria, and the inhibition of adult neurogenesis. J. Neurosci. Res. 2011, 89, 1989-1996). 35

Melatonin is an endogenous hormone produced in different tissues of the body, such as the pineal gland, the retina and the gastrointestinal tract. It participates in a wide variety of pathophysiological processes, including the regulation of the circadian cycle, the immune system and the endogenous antioxidant system. It is a proven fact that 5 levels of melatonin decrease with age and that this deficiency is associated with insomnia and depression. Recent research has also linked low levels of melatonin with aging and the development of neurodegenerative diseases, such as Alzheimer's (Bubenik, GA; Konturek, SJ Melatonin and aging: prospects for human treatment. J. Physiol. Pharmacol. 2011, 62, 13-10 19).

Many of the pharmacological effects of melatonin are due to its direct interaction with its two main receptors, called MT1 and MT2, to its potent antioxidant activity as a free radical scavenger, or indirectly to its interaction with nuclear receptors. However, as a drug, melatonin has a very short half-life due to its rapid metabolism, which makes it advisable to have other ligands of the melatoninergic system that are metabolically more stable, in order to achieve a therapeutic effect superior to that of the own melatonin (Boutin, JA; Audinot, V .; Ferry, G .; Delagrange, P. Molecular tools to study melatonin pathways and actions. 20 Trends Pharmacol. Sci. 2005, 26, 412-419).

In addition to the benefits of the circadian cycle and sleep problems, melatonin receptor ligands have interesting properties in the CNS, mainly anxiolytic, antipsychotic and analgesic. 25 therapeutic applications have also been found in some types of cancer, in the regulation of ovulation, in diabetes and in the treatment of obesity (Zlotos, DP Recent progress in the development of agonists and antagonists for melatonin receptors. Curr. Med .Chem. 2012, 19, 3532-3549).

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In the CNS, melatonin stimulates the synthesis of several endogenous antioxidant proteins, such as glutathione peroxidase that eliminates toxic radicals of the peroxide type. It has also been found to produce beneficial anti-amyloidogenic and anti-apoptotic effects, as well as neuroprotective effects against toxicity caused by the beta-amyloid peptide, a pathological marker characteristic of Alzheimer's disease (He, H .; Dong, W. ; 35

Huang, F. Anti-amyloidogenic and anti-apoptotic role of melatonin in Alzheimer disease. Curr. Neuropharmacol 2010, 8, 211-217).

Recently, the in vivo effects of melatonin have been studied, using different murine models of Alzheimer's disease, finding very interesting results. In APP-695 transgenic mice it has been proven that this molecule is capable of increasing learning and memory capacity (Feng, Z .; Chang, Y .; Cheng, Y .; Zhang, BL; Qu, ZW; Qin, C .; Zhang, JT Melatonin alleviates behavioral deficits associated with apoptosis and cholinergic system dysfunction in the APP 695 transgenic mouse model of Alzheimer's disease. J. Pineal. Res. 2004, 37, 129-136). Using mice with the double APP / Ps1 mutation, the effects of melatonin on cerebral mitochondrial function have been studied, finding that the administration of this substance decreases between 2 and 4 times the levels of beta-amyloid peptide in different regions of the brain . And what is more interesting, this effect is accompanied by a complete recovery of mitochondrial respiratory rate, membrane potential and ATP levels in isolated mitochondria of the hippocampus, cortex and striatum (Dragicevic, 15 N .; Copes, N .; O'Neal-Moffitt, G .; Jin, J .; Buzzeo, R .; Mamcarz, M .; Tan, J .; Cao, C .; Olcese, JM; Arendash, GW; Bradshaw , PC Melatonin treatment mitochondrial restores function in Alzheimer's mice: a mitochondrial protective role of melatonin membrane receptor signaling. J. Pineal Res. 2011, 51, 75-86). Therefore, melatoninergic system ligands improve mitochondrial energy metabolism and can be considered 20 innovative drugs for the treatment of neurodegenerative diseases, such as Alzheimer's.

Even more recent results have shown that a melatonin supplement delays the normal decrease of neurogenesis in the hippocampus during the aging process of mice (Ramírez-Rodríguez, G .; Vega-Rivera, NM; Benítez-King, G. ; Castro-García, M .; Ortiz-López, L. Melatonin supplementation delays the decline of adult hippocampal neurogenesis during normal aging of mice. Neurosci. Lett. 2012, 530, 53-58). On the other hand, in mice subjected to transient cerebral ischemia-reperfusion damage as a stroke model, it has been observed that melatonin increases the survival of all 30 animals and improves neuronal function, even when administered 2 hours after the brain accident -vascular. Melatonin increases neurogenesis and cell proliferation in the twilight regions of the infarcted regions, these effects being counteracted by melatonin receptor antagonists. Therefore, the activation of melatonin receptors by melatoninergic ligands could be a treatment.

Innovative for diseases that involve neuronal loss, such as neurodegenerations and cerebrovascular accidents, among others (Chern, CM; Liao, JF; Wang, YH; Shen, YC Melatonin ameliorates neural function by promoting endogenous neurogenesis through the MT2 melatonin receptor in ischemic-stroke mice. Free Radic. Biol. Med. 2012, 52, 1634-1647). 5

EXPLANATION OF THE INVENTION

A neurogenic compound based on melatonin and of general formula (I) constitutes a first object of the present invention:

its pharmaceutically acceptable salts, pro-drugs or solvates,

 fifteen

where R1 is H, (C1-C6) alkyl or (C1-C6) alkoxy

n = 1-6

X is O or N, with the particularity that when X is O, Y is N, L1 is absent and L2 is alkenyl or alkynyl

Y is O or N, with the particularity that when Y is O, X is N and L1 and L2 give rise to a 5-membered aromatic heterocycle comprising up to 3 heteroatoms and which can be substituted by hydrogen, (C1-) alkyl C6), hydroxyl, (C1-C6) alkoxy, thiol or mercaptoalkyl (C1-C6)

L2 is alkenyl, alkynyl (when X is O) or together with L1 forms a 5-membered aromatic heterocycle comprising up to 3 heteroatoms and which may be substituted by hydrogen, (C1-C6) alkyl, hydroxyl, (C1-C6) alkoxy ), thiol or mercaptoalkyl (C1-C6)

In a preferred embodiment, in the compound of general formula (I), X is O, Y is N, n is equal to 1 or 2 and L2 is allyl (prop-2-en-1-yl) or prop-2- in-1-yl, according to formula (II):

Formula (II)

 5

In another preferred embodiment, in the compound of general formula (I), X is N, Y is O, n is equal to 1 or 2 and L1 and L2 form a 5-membered aromatic heterocycle and two heteroatoms substituted with a methyl, according to the formula (III):

Formula (III) 10

In another preferred embodiment, in the compound of general formula (I), X is N, Y is O, n is equal to 1 or 2 and L1 and L2 form a 5-membered aromatic heterocycle and three heteroatoms substituted with a methyl according to the formula (IV):

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Formula (IV)

In another preferred embodiment, in the compound of general formula (I), X is N, Y is O, n is equal to 1 or 2, and L1 and L2 form a 5-membered and three heteroatom aromatic heterocycle substituted with a radical R2 which is methyl, hydroxyl or thiol according to formula (V):

Formula (V) 5

In another preferred embodiment, in the compound of general formula (I), where X is N, Y is N, n is equal to 1 or 2, and L1 and L2 form a 5-membered and three heteroatom aromatic heterocycle substituted with a radical R2 which is hydroxyl or thiol and an R3 radical which is alkyl according to formula (VI):

Formula (VI)

In other preferred embodiments, the compound is selected from the following group:

• N-Alyl-2- (5-methoxy-1H-indole-3-yl) acetamide (1) 15

• N-Alyl-3- (5-methoxy-1H-indole-3-yl) propanamide (2)

• 2- (5-Methoxy-1H-indol-3-yl) -N- (prop-2-in-1-yl) acetamide (3)

• 3- (5-Methoxy-1H-indol-3-yl) -N- (prop-2-in-1-yl) propanamide (4)

• 2- (2- (1H-Indol-3-yl) ethyl) -5-methylxazole (5)

• 2 - ((1H-Indol-3-yl) methyl) -5-methylxazole (6) 20

• 2 - ((5-Methoxy-1H-indol-3-yl) methyl) -5-methylxazole (7)

• 2- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -5-methylxazole (8)

• 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -3-methyl-1,2,4-oxadiazole (9)

• 5- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -3-methyl-1,2,4-oxadiazole (10)

• 2- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -5-methyl-1,3,4-oxadiazole (11)

• 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -1,3,4-oxadiazol-2-ol (12)

• 5- (2- (1H-Indol-3-yl) ethyl) -1,3,4-oxadiazol-2-ol (13)

• 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -1,3,4-oxadiazol-2-thiol (14)

• 5- (2- (1H-Indol-3-yl) ethyl) -1,3,4-oxadiazol-2-thiol (15) 5

• 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -4-methyl-4H-1,2,4-triazol-3-ol (16)

• 5 - ((1H-Indol-3-yl) methyl) -4-methyl-4H-1,2,4-triazol-3-ol (17)

• 4-Ethyl-5 - ((5-methoxy-1H-indol-3-yl) methyl) -4H-1,2,4-triazol-3-thiol (18)

• 5 - ((1H-Indol-3-yl) methyl) -4-ethyl-4H-1,2,4-triazol-3-thiol (19)

or an isomer, a solvate, a pro-drug or a pharmaceutically acceptable salt thereof.

It is also an object of the present invention, a process for obtaining a compound of general formula (II) according to claims 1 and 2, consisting of the treatment of the corresponding carboxylic acid derived from 1H-indole-3-yl in dry acetonitrile 15 with allylamine or propargilamine in the presence of 1,1'-carbonyldiimidazole (CDI) and 4- (dimethylamino) pyridine (DMAP).

In a preferred embodiment, the compound of general formula (III) is obtained by a procedure consisting of the treatment of the corresponding N- (prop-2-inyl) alkylamide 20 derived from 1H-indole-3-yl in dry dichloromethane with chloride of gold (III).

 In another preferred embodiment, the compound of general formula (IV) is obtained by a process consisting of the reaction of an alkyl ester of the corresponding carboxylic acid derived from 1H-indole-3-yl with acetamidoxime in the presence of sodium hydride. 25

 In another preferred embodiment, the compound of general formula (V) is obtained by a procedure consisting of the reaction of the corresponding 1H-indole-3-yl carboxylic acid in dry acetonitrile with the corresponding substituted hydrazide in the presence of 1.1 ' -carbonyldiimidazole (CDI) and 4- (dimethylamino) pyridine (DMAP), followed by treatment with phosphorus oxychloride.

 In another preferred embodiment, the compound of general formula (VI) is obtained by a process consisting of the hydrazide reaction of the corresponding carboxylic acid.

1H-indole-3-yl derivative with an isocyanate or isothiocyanate substituted in a mixture of acetic acid and water, followed by treatment with sodium hydroxide in ethanol.

A further object of the present invention is a pharmaceutical composition comprising a compound of formula (I) to (VI), and may also include another active principle. In a preferred embodiment, the pharmaceutical composition is suitable for oral administration.

It is also an object of the present invention to use the melatonin-based neurogenic compounds according to any one of the general formulas (I) to 10 (VI) or those selected from the compounds (1) to (19) in the preparation of a medicament or pharmaceutical composition for the treatment of diseases of the nervous system that are selected from neurodegenerative diseases, cognitive disorders, psychiatric diseases or disorders, traumas or cell injuries, neurological conditions and diseases or disorders related to the disease. circadian cycle.

In a preferred embodiment, neurodegenerative disease is selected from Alzheimer's disease, Creutzfeld-Jacob disease, Parkinson's disease, systemic amyloidosis, amyotrophic lateral sclerosis, degenerative retinal disease, cerebral palsy, as well as a combination of same.

In another preferred embodiment, the cognitive disorder is selected from memory impairment, memory loss separated from dementia, mild cognitive impairment, age-related cognitive decline, memory loss due to attention deficit, cognitive impairment as a consequence of the use of general anesthetics, chemotherapy or radiotherapy, cognitive impairment associated with post-surgical trauma or therapeutic intervention, cognitive decline associated with Alzheimer's disease or with epilepsy, senile dementia, vascular dementia, delirium, as well as related diseases or a combination of same. 30

In another preferred embodiment, the psychiatric illness or disorder is selected from depression, major depression, neurotic depression, depression caused by drug or alcohol use, post-traumatic depression, postpartum depression, anxiety, disorder

obsessive-compulsive, bipolar disorder, social phobia, seasonal mood disorder, as well as related diseases or a combination thereof.

In another preferred embodiment, the trauma or cell injury is selected from trauma or neurological injury, brain or spinal cord surgery, retinal injury, lesions related to epilepsy, brain or spinal cord injuries in relation to the treatment of the cancer, brain or spinal cord injuries related to infections, inflammatory processes, environmental toxins, ischemic events, as well as related diseases or a combination thereof.

 10

In another preferred embodiment, the neurological condition is selected from learning disorder, autism, attention deficit disorder, narcolepsy, sleep disorder, epilepsy, temporal lobe epilepsy, as well as related diseases or a combination thereof.

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In another preferred embodiment, the disease or disorder related to the circadian cycle is selected from sleep disorders, daytime fatigue, loss of mental efficacy, weakness and irritability and transoceanic syndrome, as well as related diseases or a combination thereof.

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Finally, it is also an object of the present invention to use the neurogenic compounds based on melatonin, according to any one of the general formulas (I) to (VI) or those selected from the compounds (1) to (19), as a reagent in biological tests.

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DETAILED DESCRIPTION OF THE INVENTION

The invention relates to the synthesis of new products of general formula (I) and their use in the treatment of diseases of the nervous system related to neuronal degeneration, psychiatric and cognitive disorders, mood disorders, trauma or tissue injury, or Another related neurological disorder, in which increased neurogenesis, modulation of melatonin and / or serotonin receptors, antioxidant properties and / or cholinergic properties cure or relieve the condition or disorder.

 35

In a first aspect, the invention relates to a compound of general formula (I):

where

R1 is H, (C1-C6) alkyl or (C1-C6) alkoxy

n = 1-6

X is O or N, with the particularity that when X is O, Y is N, L1 is absent and L2 is alkenyl or alkynyl

Y is O or N, with the particularity that when Y is O, X is N and L1 and L2 give rise to a 5-membered aromatic heterocycle comprising up to 3 heteroatoms and which may be substituted by hydrogen, (C1-C6) alkyl ), hydroxyl, (C1-C6) alkoxy, thiol or mercaptoalkyl (C1-C6)

L2 is alkenyl, alkynyl (when X is O) or together with L1 forms a 5-membered aromatic heterocycle comprising up to 3 heteroatoms and which may be substituted by hydrogen, (C1-C6) alkyl, hydroxyl, (C1-C6) alkoxy , thiol or mercaptoalkyl (C1-C6)

 twenty

or an isomer, a solvate, a pro-drug or a pharmaceutically acceptable salt thereof.

In the above definition of the compounds of general formula (I), the following terms have the indicated meaning:

 25

The term "alkyl" refers to radicals of hydrocarbon chains, linear or branched, consisting of carbon and hydrogen atoms, which have no unsaturation,

that have 1 to 6 carbon atoms and that bind to the rest of the molecule by a single bond, for example, methyl, ethyl, n-propyl, i-propyl, n-butyl, tert-butyl, sec-butyl, n-pentyl or n-hexyl.

The term "alkoxy" refers to a radical of formula O-R where R is an alkyl group 5 as defined above, for example, methoxy, ethoxy, propoxy, etc.

The term "alkenyl" refers to radicals of linear or branched hydrocarbon chains containing one or more double carbon-carbon bonds, for example, vinyl, 1-propenyl, allyl, isoprenyl, 2-butenyl, 1,3-butadienyl, etc. . Alkenyl radicals may optionally be substituted by one or more substituents such as halogen, hydroxy, alkoxy, carboxyl, cyano, carbonyl, acyl, alkoxycarbonyl, amino, nitro, mercapto and alkylthio.

 The term "alkynyl" refers to radicals of straight or branched hydrocarbon chains containing at least one triple carbon-carbon bond, for example, ethynyl and propynyl. Alkynyl radicals can be optionally substituted by one or more substituents such as halogen, hydroxy, alkoxy, carboxyl, cyano, carbonyl, acyl, alkoxycarbonyl, amino, nitro, mercapto and alkylthio.

The term "heterocycle" refers to a stable 5-membered monocyclic radical, which is unsaturated, saturated or partially saturated, and is formed by carbon atoms and at least two heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur. .

"Halogen" or "halo" refers to fluorine, chlorine, bromine or iodine. 25

The term "mercaptoalkyl" refers to a radical of formula S-R where R is an alkyl group as defined above, for example, mercaptomethyl, mercaptoethyl, mercaptopropyl, etc.

 30

The compounds covered by this invention include the compounds defined in the general formulas, in the claims and those described in the examples.

The invention also includes those compounds that differ only in the presence of one or more isotopically enriched atoms. For example, the compounds that have the 35

present structures, except for the replacement of a hydrogen with a deuterium or tritium, or the substitution of a carbon for a carbon enriched in 13C or 14C or a nitrogen enriched in 15N, are within the scope of this invention.

The compounds of the present invention represented by formula (I) may include 5 isomers, depending on the presence of multiple bonds, including optical or enantiomeric isomers, depending on the presence of chiral centers. The individual isomers, enantiomers or diastereoisomers and mixtures thereof fall within the scope of the present invention, that is, the term isomer also refers to any mixture of isomers, such as diastereomers, racemic, etc., even its isomers. optically active or mixtures in different proportions thereof. The individual enantiomers or diastereoisomers, as well as mixtures thereof, can be separated by conventional techniques.

Also, within the scope of this invention are pharmaceutically acceptable salts, solvates and pro-drugs of the compounds of formula (I) or any other compound that, when administered to a patient, is capable of providing (directly or indirectly) a compound as described herein. However, it will be appreciated that pharmaceutically acceptable salts are also within the scope of the invention since these may be useful in the preparation of pharmaceutically acceptable salts. The preparation of salts, solvates, pro-drugs and derivatives can be carried out by methods known in the art.

The term "prodrug" or "pro-drug" as used herein includes any compound derived from a compound of formula (I), such as and not limited to: esters 25 (including esters of carboxylic acids, esters of amino acids, esters phosphate, sulphonate esters of metal salts, etc.), carbamates, amides, etc., which when administered to an individual can be transformed directly or indirectly into said compound of formula (I) in said individual. Advantageously, said derivative is a compound that increases the bioavailability of the compound of formula (I) when administered to an individual or that enhances the release of the compound of formula (I) in a biological compartment. The nature of said derivative is not critical as long as it can be administered to an individual and provides the compound of formula (I) in a biological compartment of an individual. The preparation of said pro-drug can be carried out by conventional methods known to those skilled in the art. 35

For example, pharmaceutically acceptable salts of compounds provided herein are synthesized by conventional chemical methods from an original compound containing a basic or acidic moiety. Generally, such salts are prepared, for example, by reacting the free acid or base forms of the 5 compounds with a stoichiometric amount of the appropriate base or acid in water or in an organic solvent or in a mixture of the two. Generally, non-aqueous media such as ether, ethyl acetate, ethanol, isopropanol or acetonitrile are preferred. Examples of acid addition salts include mineral acid salts such as, for example, hydrochloride, hydrobromide, iodhydrate, sulfate, nitrate, phosphate and organic acid addition salts such as, for example, acetate, maleate, fumarate, citrate. , oxalate, succinate, tartrate, malate, mandelate, methanesulfonate and p-toluenesulfonate. Examples of base addition salts include inorganic salts such as, for example, sodium, potassium, calcium, ammonium, magnesium, aluminum and lithium salts, and salts of organic bases such as, for example, ethylenediamine, ethanolamine, N, N -dialkylene ethanolamine, triethanolamine, glucamine and salts of basic amino acids.

Particularly preferred derivatives or pro-drugs are those that increase the bioavailability of the compounds of this invention when such compounds are administered to a patient (for example, by making a compound administered orally more easily absorbed by blood), or that enhances the release of the original compound in a biological compartment (for example, the brain or lymphatic system) in relation to the original species.

Any compound that is a pro-drug of a compound of general formula (I) is within the scope of the invention. The term "pro-drug" is used in its broadest sense and encompasses those derivatives that are converted in vivo into the compounds of the invention. Such derivatives will be apparent to those skilled in the art, and include, depending on the functional groups present in the molecule and without limitation, the following derivatives of the compounds: esters, amino acid esters, phosphate esters, salt sulphonate esters metallic, carbamates and amides.

The compounds of general formula (I) may be in crystalline form as free compounds or as solvates and are both forms within the scope of the present invention. Solvation methods are generally known within the art. The Solvates 35

Suitable are pharmaceutically acceptable solvates. In a particular embodiment, the solvate is a hydrate.

For application in therapy, the compounds of formula (I), their salts, pro-drugs or solvates, will preferably be found in a pharmaceutically acceptable or substantially pure form, that is, having a pharmaceutically acceptable level of purity excluding normal pharmaceutical additives such as diluents and carriers, and not including material considered toxic at normal dosage levels. The purity levels for the active ingredient are preferably greater than 50%, more preferably, greater than 70%, and still more preferably, greater than 90%. In a preferred embodiment, they are greater than 95% of the compound of formula (I), or of its salts, solvates or pro-drugs.

The compounds of formula (I), their pharmaceutically acceptable salts, prodrugs or solvates thereof, can therefore be used in the prevention and / or treatment of a disease or condition, in which the increase in neurogenesis, the modulation of the melatonin and / or serotonin receptors, the antioxidant properties and the anticholinergic properties of the compounds of the invention prevent, cure or alleviate said disease or condition. Pharmaceutical compositions containing a therapeutically effective amount of a compound of formula (I), its pharmaceutically acceptable salts, prodrugs or solvates thereof, together with pharmaceutically acceptable excipients, constitute a further aspect of the present invention.

The amount of compound of formula (I), its pharmaceutically acceptable salts, prodrugs or solvates thereof, therapeutically effective to be administered as well as its dosage to treat a pathological state with said compounds will depend on numerous factors, among which is the age, the patient's condition, the severity of the disease, the route and frequency of administration, the modulator compound to be used, etc.

 30

The present invention further relates to the compounds of formulas (I) to (VI) for the manufacture of a medicament.

A further aspect of the present invention relates to a pharmaceutical composition comprising the compounds of formulas (I) to (VI) as previously defined and at least one pharmaceutically acceptable excipient, adjuvant and / or carrier.

The pharmaceutical compositions may be administered by any appropriate route of administration, for example, oral, parenteral (subcutaneous, intraperitoneal, intravenous, intramuscular, etc.), rectal, etc.

In a particular embodiment, said pharmaceutical compositions may be in a pharmaceutical form for oral administration, either in solid or liquid form. Illustrative examples of pharmaceutical forms of oral administration include tablets, capsules, granules, solutions, suspensions, etc., and may contain conventional excipients, such as binders, diluents, disintegrants, lubricants, humectants, etc., and may be prepared by conventional methods. The pharmaceutical compositions may also be adapted for parenteral administration, in the form of, for example, sterile lyophilized solutions, suspensions or products, in the appropriate dosage form; in this case, said pharmaceutical compositions will include suitable excipients, such as buffers, surfactants, etc. In any case, the excipients will be chosen based on the pharmaceutical form of administration selected. A review of the different pharmaceutical forms of drug administration and their preparation can be found in the book “Treaty of Pharmacy Galenica”, by C. Faulí i Trillo, 10 Edition, 1993, Luzán 5, S.A. of Editions, or in any book of similar characteristics that exists in each country.

Since the compounds of the present invention result in increased neurogenesis, modulate the melatonin and / or serotonin receptors and exhibit antioxidant and / or cholinergic properties, said compounds may be useful for the preparation of a medicament or a pharmaceutical composition for the treatment of diseases of the nervous system related to neuronal degeneration, psychiatric and cognitive disorders, trauma or cell injury, or other related neurological disorder. Also for the treatment of diseases or disorders related to the circadian cycle.

Neural degeneration includes a neurodegenerative disorder, a neural stem cell disorder, a neural progenitor cell disorder, an episode 35

Ischemic or a combination thereof. In further embodiments, neurodegenerative disorders include, but are not limited to, Alzheimer's disease, prion pathologies (eg, Creutzfeld-Jacob disease), Parkinson's disease, systemic amyloidosis, amyotrophic lateral sclerosis, degenerative disease of the retina, cerebral palsy or a combination thereof. Cognitive disorders 5 include senile dementia, vascular dementia, cognitive impairment, attention deficit disorder, as well as related disorders or a combination thereof.

Psychiatric conditions include, but are not limited to, depression, neurotic depression, depression caused by drug and / or alcohol use, post-traumatic depression, postpartum depression, anxiety, obsessive-compulsive disorder, bipolar disorder, social phobia , seasonal mood disorder and its combinations.

Cognitive disorders include, but are not limited to, memory impairment, memory loss separate from dementia, mild cognitive impairment, age-related cognitive impairment, cognitive impairment as a result of the use of general anesthetics, chemotherapy, radiation treatment, post-surgical trauma, therapeutic intervention, cognitive decline associated with Alzheimer's disease or epilepsy, dementia, delirium, or a combination thereof.

 twenty

In another aspect, the compounds defined above and the compositions derived therefrom are used to treat trauma or cell injury, including neurological trauma or injury, brain or spinal cord surgery, retinal injury, epilepsy-related injuries, injuries brain or spinal cord, brain or spinal cord injuries in relation to cancer treatment, brain or spinal cord injuries related to infections, inflammatory processes, environmental toxins, ischemic episodes, or a combination thereof.

In another aspect, the compounds and compositions object of the present patent are used to treat neurological conditions, such as learning disorder, autism, attention deficit disorder, narcolepsy, sleep disorder, epilepsy, temporal lobe epilepsy, or a combination thereof.

In another aspect, the compounds and compositions object of the present patent are used to treat the symptoms related to the circadian cycle or the time alteration.

such as: sleep disorders, daytime fatigue, loss of mental efficacy, weakness and irritability and transoceanic syndrome.

The present invention also relates to a compound of formula (I) as defined above for use in the treatment and / or prevention of a disease related to neurogenesis, modulation of melatonin receptors and / or of serotonin, presence of antioxidants and / or cholinesterase inhibition.

The present invention also relates to a method for the prevention or treatment of a disease related to neurogenesis, the modulation of the 10 melatonin and / or serotonin receptors, the presence of antioxidants and / or the inhibition of cholinesterase, which comprises the administration to a patient in need of a therapeutically effective amount of a compound of formula (I) as previously defined.

 fifteen

The compounds of the present invention can be used as reagents in biological assays. This includes its use for the study of biology and neurogenesis mechanisms, its use as ligands for melatonin and serotonin receptors, its use as antioxidant and cholinergic agents.

 twenty

The compounds of the present invention of formula (I) can be obtained or produced by a chemical synthetic route or obtained from a natural material of different origin. The following examples are given only as an additional illustration of the invention, they should not be taken as a definition of the limits of the invention.

 25

Schemes 1-5 show the procedures for the preparation of the compounds of the invention of general formulas (II) - (VI). For example, treatment of the corresponding carboxylic acid derived from 1H-indole-3-yl in dry acetonitrile with allylamine or propargilamine in the presence of 1,1'-carbonyldiimidazole (CDI) and 4- (dimethylamino) pyridine (DMAP) led to obtaining the products of general formula 30 (II) (Scheme 1).

Scheme 1

The treatment of the corresponding N- (prop-2-inyl) alkylamide derived from 1H-indole-3-yl in dry dichloromethane with gold chloride (III) allowed to obtain the compounds of general formula (III) (Scheme 2).

Scheme 2

 10

Reaction of an alkyl ester of the corresponding carboxylic acid derived from 1H-indole-3-yl with acetamidoxime in the presence of sodium hydride provided the compounds of general formula (IV) (Scheme 3).

 fifteen

Scheme 3

The reaction of the corresponding carboxylic acid derived from 1H-indole-3-yl in dry acetonitrile with the corresponding substituted hydrazide in the presence of 1,1'-carbonyldiimidazole (CDI) and 4- (dimethylamino) pyridine (DMAP), followed by treatment with Phosphorus oxychloride 20 led to the compounds of general formula (V) (Scheme 4).

Scheme 4

The reaction of the hydrazide of the corresponding carboxylic acid derived from 1H-indole-3-yl with an isocyanate or substituted isothiocyanate in a mixture of acetic acid and water, followed by treatment with sodium hydroxide in ethanol, led to the compounds of the general formula (VI) (Scheme 5).

Scheme 5 10

The compounds of the present invention can be purified by conventional methods, such as crystallization or chromatography. When the chemical synthesis process leads to mixtures of isomers, they can be separated by conventional techniques such as preparative chromatography. In the case of stereogenic centers, the 15 compounds can be obtained in racemic form or the pure enantiomers can be prepared by stereoselective, stereospecific synthesis or by resolution.

BRIEF DESCRIPTION OF THE FIGURES 20

Figure 1. Neuronal stem cell cultures of adult Wistar rats treated with vehicle (basal), melatonin (endogenous ligand of MT receptors), luzindole (antagonist of MT receptors), 4, 11 and 14, all at a concentration of 10 micromolar for 48 hours. The anti-beta-tubulin antibody (clone Tuj1) was used as a marker associated with early neurogenesis.

Figure 2. Neuronal stem cell cultures of adult Wistar rats treated with vehicle (basal), melatonin (endogenous ligand of MT receptors), luzindole (antagonist of MT receptors), 4, 11 and 14, all at a concentration of 10 micromolar for 48 hours. The MAP-2 antibody (microtubule-associated protein 2) was used as a marker associated with neuronal maturity. 5

MODE OF EMBODIMENT OF THE INVENTION

1. Synthesis of the compounds of the invention

 10

N-Alyl-2- (5-methoxy-1H-indol-3-yl) acetamide (1). On a solution of 2- (5-methoxy-1H-indole-3-yl) acetic acid (172 mg, 0.84 mmol) in 20 mL of dry acetonitrile, carbonyldiimidazole (CDI) (163 mg, 1 mmol) and 4 - (dimethylamino) pyridine (DMAP) (10 mg, 0.08 mmol). After stirring for 2 hours at 50 ° C, allylamine (92 µL, 1.26 mmol) was added, maintaining the reaction at room temperature for an additional 2 hours. After removal of the solvent under reduced pressure, a crude was obtained which was treated with 1M HCl (20 mL) and the resulting suspension was extracted with ethyl acetate (3 x 20 mL). The organic phase was washed with 2 M NaOH (3 x 20 mL), dried with anhydrous magnesium sulfate and the solvent was removed in vacuo, yielding 1 (178 mg, 86%) as a yellow oil that crystallized on rest. 1H NMR (300 MHz, DMSO-d6) δ 10.71 - 10.66 (s, 1H), 8.05 - 7.97 (m, 20 1H), 7.24 - 7.19 (d, J = 8.7 Hz, 1H), 7.14 - 7.12 (d, J = 2.2 Hz, 1H), 7.07 - 7.04 (d, J = 2.3 Hz, 1H), 6.74 - 6.67 (dd, J = 8.7, 2.4 Hz, 1H), 5.85 - 5.70 (ddt, J = 17.1, 10.3, 5.2 Hz, 1H), 5.12 - 5.05 (dd, J = 17.2, 1.8 Hz, 1H), 5.03 - 4.97 (dd, J = 10.3, 1.7 Hz, 1H), 3.74 - 3.72 (s, 3H), 3.71 - 3.66 (m, 2H), 3.48-3.48 (s, 2H). 13C NMR (75 MHz, DMSO-d6) δ 170.51, 152.96, 135.49, 131.21, 127.49, 124.42, 114.85, 111.90, 111.04, 108.61, 100.53, 55.30, 25 40.90, 32.70. HPLC-MS (m / z) [MH +] 245.

N-Alyl-3- (5-methoxy-1H-indole-3-yl) propanamide (2). According to the preparation of N-allyl-2- (5-methoxy-1H-indol-3-yl) acetamide (1), from 3- (5-methoxy-1H-indole-3-yl) propanoic acid (80 mg, 0.36 mmol), 2 (81 mg, 87%) was obtained as a brown solid. 1H 30 NMR (300 MHz, DMSO-d6) δ 10.62 - 10.54 (s, 1H), 8.03 - 7.93 (t, J = 5.5 Hz, 1H), 7.22 - 7.16 (d, J = 8.7 Hz, 1H), 7.05 - 7.01 (d, J = 2.3 Hz, 1H), 6.99 - 6.97 (d, J = 2.4 Hz, 1H), 6.72 - 6.66 (dd, J = 8.7, 2.4 Hz, 1H), 5.83 - 5.69 (ddt, J = 17.2, 10.3, 5.2 Hz, 1H), 5.11 - 4.98 (m, 2H), 3.76 - 3.74 (s, 3H), 3.71 - 3.65 (tt, J = 5.6, 1.7 Hz, 2H), 2.92 - 2.83 (t , J = 7.7 Hz, 2H), 2.48 - 2.41 (t, J = 7.7 Hz, 2H). 13C NMR (75 MHz, DMSO-d6) δ 172.08, 153.25, 135.87, 35

131.72, 127.66, 123.14, 115.30, 113.98, 112.25, 111.34, 100.62, 55.72, 41.18, 36.48, 21.44. HPLC-MS (m / z) [MH +] 259.

2- (5-Methoxy-1H-indol-3-yl) -N- (prop-2-in-1-yl) acetamide (3). Following a method similar to the previous one to obtain 1, from 2- (5-methoxy-1H-indole-3-yl) acetic acid (200 mg, 1.5 mmol) and propargilamine (0.64 ml, 1 mmol) obtained 3 (146 mg, 61%) as a white solid. 1H NMR (500 MHz, DMSO-d6) δ 10.70 (s, 1H), 8.33 (t, J = 5.5 Hz, 1H), 7.22 (d, J = 8.7 Hz, 1H), 7.13 (d, J = 2.4 Hz , 1H), 7.04 (d, J = 2.4 Hz, 1H), 6.71 (dd, J = 8.7, 2.5 Hz, 1H), 3.85 (dd, J = 5.6, 2.6 Hz, 2H), 3.75 (s, 3H) , 3.47 (s, 2H), 3.08 (t, J = 2.5 Hz, 1H). 13C NMR (126 MHz, DMSO-d6) δ 170.91, 153.45, 131.65, 127.93, 124.87, 112.36, 111.53, 108.73, 10 100.99, 81.81, 73.26, 55.79, 32.93, 28.39. HPLC-MS (m / z) [MH +] 243.

3- (5-Methoxy-1H-indol-3-yl) -N- (prop-2-in-1-yl) propanamide (4). Using the method described to obtain 1, from 2- (5-methoxy-1H-indole-3-yl) propanoic acid (192 mg, 1 mmol) and propargilamine (0.71 ml, 1.1 mmol) was obtained 4 (160 mg, 65%) as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 10.57 (s, 1H), 8.29 (s, 1H), 7.18 (d, J = 8.7 Hz, 1H), 7.02 (s, 1H), 6.97 (s, 1H) , 6.68 (d, J = 8.6 Hz, 1H), 3.90 - 3.80 (m, 2H), 3.74 (s, 3H), 3.09 - 3.07 (t, J = 2.7 Hz, 2H), 2.85 (t, J = 7.7 Hz, 2H), 2.42 (t, J = 6.8 Hz, 2H). 13C NMR (75 MHz, Acetone-d6) δ 173.16, 155.26, 133.31, 129.32, 124.06, 115.76, 113.29, 112.93, 101.79, 82.19, 72.44, 56.54, 37.93, 29.38, 22.53. HPLC-MS (m / z) [MH +] 257. 20

2- (2- (1H-Indol-3-yl) ethyl) -5-methylxazole (5). To a solution of 3- (1H-indole-3-yl) -N- (prop-2-inyl) propanamide (377 mg, 1.67 mmol) in 20 mL of dry dichloromethane was added gold chloride (III) (50 mg 0.167 mmol) and the reaction was stirred at room temperature under an inert atmosphere for 18 h. After this time, triethylamine (0.5 mL) was added and the resulting mixture was filtered over a short column of silica gel eluting with ethyl acetate. The solvent was evaporated in vacuo and the resulting oil was chromatographed on silica gel to give 5 (23 mg, 7%). 1H NMR (300 MHz, Methanol-d4) δ 10.14 (s, 1H), 7.45 (dt, J = 7.8, 1.0 Hz, 1H), 7.30 (dt, J = 8.1, 1.0 z, 1H), 7.07 (ddd, J = 8.2, 7.0, 1.3 Hz, 1H), 7.04 - 6.91 (t, J = 7.8, 1H; s, 1H), 6.57 (s, 1H), 3.12 (t, J = 8.1 z, 2H), 3.02 ( t, J = 8.1 Hz, 2H), 2.19 (s, 30 3H). 13C-NMR (75 MHz, Methanol-d4) δ 164.4, 148.6, 138.3, 127.0, 126.0, 123.8, 121.7, 120.0, 119.1, 113.5, 109.8, 117.3, 111.0, 31.8, 30.2, 22.5. HPLC-MS (m / z) [MH +] 227.

2 - ((1H-Indol-3-yl) methyl) -5-methylxazole (6). From 2- (1H-indole-3-yl) -N- (prop-2-inyl) acetamide (268 mg, 1.26 mmol), compound 6 was obtained as a white powder (76 35

mg, 29%), according to the synthesis described for 5. 1H NMR (300 MHz, DMSO-d6) δ 10.94 (s, 1H), 7.46 (d, J = 7.8 Hz, 1H), 7.33 (d, J = 8.1 Hz, 1H), 7.24 (d, J = 2.3 Hz, 1H), 7.06 (t, J = 7.5 Hz, 1H), 6.96 (t, J = 7.5 Hz, 1H), 6.68 (s, 1H), 4.11 (s, 2H), 2.19 (s, 3H). HPLC-MS (m / z) [MH +] 241.

 5

2 - ((5-Methoxy-1H-indol-3-yl) methyl) -5-methylxazole (7). According to the synthesis described for 5, from 3 (100 mg, 0.41 mmol), compound 7 was obtained as a pale solid (18 mg, 18%). 1H NMR (300 MHz, CDCl3) δ 8.35 (s, 1H), 7.25 (d, J = 8.8 1H), 7.17 - 7.05 (m, 2H), 6.85 (dd, J = 8.7, 2.5 Hz, 1H), 6.66 (s, 1H), 4.21 (s, 2H), 3.85 (s, 3H), 2.26 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 161.52, 155.48, 144.90, 133.81, 128.38, 129.21, 124.04, 10 112.82, 112.72, 109.16, 106.68, 56.87, 28.43, 13.14. HPLC-MS (m / z) [MH +] 243.

2- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -5-methylxazole (8). According to the synthesis described for 5, from 4 (30 mg, 0.11 mmol) 8 was obtained as a light brown solid (11 mg, 38%). 1H NMR (300 MHz, CDCl3) δ 7.94 (s, 1H), 7.25 (d, J = 8.8 Hz, 1H), 7.03 (d, J = 2.3 Hz, 15 1H), 7.00 (s, 1H), 6.86 ( dd, J = 8.8, 2.4 Hz, 1H), 6.64 (s, 1H), 3.87 (s, 3H), 3.24 - 3.17 (m, 2H), 3.11 (ddd, J = 9.4, 6.1, 2.0 Hz, 2H) 2.29 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 166.32, 155.90, 145.49, 131.08, 127.71, 128.10, 123.63, 112.61, 111.72, 110.01, 105.79, 55.46, 28.28, 24.97, 12.43. HPLC-MS (m / z) [MH +] 257.

 twenty

5 - ((5-Methoxy-1H-indol-3-yl) methyl) -3-methyl-1,2,4-oxadiazole (9). 2- (5-Methoxy-1H-indole-3-yl) ethyl acetate (150 mg, 0.64 mmol) is added over a mixture of acetamidoxime (150 mg, 0.64 mmol), sodium hydride (61 mg, 2.5 mmol) and Molecular sieve (1.5 mg) in anhydrous THF (5 mL) previously stirred and heated at 50 ° C for 2 hours. After the addition the stirring is maintained for 2 hours at 80 ° C after which the mixture is filtered and the solvent is evaporated. The resulting crude is purified by chromatography to give 9 (87 mg, 56%) as a white solid. 1H NMR (300 MHz, CDCl3) δ 8.01 (s, 1H), 7.30 - 7.23 (m, 1H), 7.20 (d, J = 2.6 Hz, 1H), 7.05 (d, J = 2.4 Hz, 1H), 6.88 (dd, J = 8.8, 2.4 Hz, 1H), 4.31 (s, 2H), 3.86 (s, 2H), 2.37 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 178.23, 167.24, 154.38, 131.23, 127.15, 123.74, 112.89, 112.06, 107.76, 100.33, 55.88, 23.26, 11.60. HPLC-MS (m / z) [MH +] 244. 30

5- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -3-methyl-1,2,4-oxadiazole (10). Following a procedure similar to the previous one, from ethyl 3- (5-methoxy-1H-indole-3-yl) propanate (173 mg, 0.7 mmol), 10 (80 mg, 45%) was obtained as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 10.64 (s, 1H), 7.20 (d, J = 8.7 Hz, 1H), 7.07 (d, J = 2.2 Hz, 1H), 6.97 (s, 1H), 6.74 - 6.60 (m, 35

1H), 3.74 (s, 3H), 3.25-3.38 (m, 2H), 3.15-3.08 (m, 2H), 2.28 (t, J = 1.2 Hz, 3H). 13C NMR (101 MHz, DMSO-d6) δ 180.04, 167.35, 153.71, 131.95, 127.73, 123.90, 112.82, 112.73, 111.95, 100.54, 55.99, 27.40, 22.58, 11.80. HPLC-MS (m / z) [MH +] 258.

2- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -5-methyl-1,3,4-oxadiazole (11). On a solution of 5 3- (5-methoxy-1H-indol-3-yl) propanoic acid (234 mg, 1 mmol) in 20 mL of dry acetonitrile were added 1,1'-carbonyldiimidazole (CDI) (163 mg, 1 mmol) and DMAP (10 mg, 0.08 mmol). After stirring for 1 hour at room temperature, acetylhydrazide (87 mg, 1.17 mmol) was added and stirring was maintained an additional 18 hours. After removal of the solvent in vacuo, a crude was obtained which was treated with 1M HCl (20 mL) and the resulting suspension was extracted with ethyl acetate (3 x 20 mL). The organic layers were combined, washed with 2 M NaOH (3 x 20 ml) and dried with anhydrous magnesium sulfate. After removal of the organic solvent under reduced pressure, N'-acetyl-3- (5-methoxy-1H-indole-3-yl) propanhydrazide (207 mg, 70%) was obtained as a white solid, which was used in the following step without purifying. 1H NMR (300 MHz, DMSO-d6) δ 10.60 (s, 1H), 9.75 (s, 1H), 9.73 15 (s, 1H), 7.19 (d, J = 8.7 Hz, 1H), 7.08 (d, J = 2.3 Hz, 1H), 6.98 (d, J = 2.5 Hz, 1H), 6.69 (dd, J = 8.8, 2.4 Hz, 1H), 3.75 (s, 3H), 2.88 (t, J = 7.7 Hz, 2H ), 2.52 - 2.37 (m, 2H), 1.83 (s, 3H). 13C NMR (101 MHz, DMSO-d6): δ (ppm) 171.4, 168.6, 153.6, 132.0, 127.9, 123.6, 113.9, 112.6, 111.7, 100.8, 56.0, 34.6, 21.4, 21.2. HPLC-MS (m / z) [MH +] 276.

 twenty

On a solution of the above intermediate hydrazide (107 mg, 0.38 mmol) in acetonitrile (2 mL) phosphorus oxychloride (0.04 mL, 0.42 mmol) was added and the mixture was heated in a microwave oven at 180 ° C for 30 min. The solvent was removed in vacuo and the residue was purified by column chromatography to give 11 (30 mg, 30%) as a white solid. 1H NMR (300 MHz, CDCl3) δ 7.91 (s, 1H), 7.26 (d, J = 8.8 Hz, 1H), 7.03 (s, 1H), 6.99 (d, J = 2.4 Hz, 25 1H), 6.87 ( dd, J = 8.8, 2.4 Hz, 1H), 3.87 (s, 3H), 3.21 (m, J = 4.7 Hz, 4H), 2.48 (s, 3H). 13C NMR (75 MHz, CDCl3) δ 166.79, 163.64, 154.05, 131.37, 127.39, 122.40, 113.78, 112.34, 111.95, 100.28, 55.93, 26.17, 22.34, 10.90. HPLC-MS (m / z) [MH +] 258.

5 - ((5-Methoxy-1H-indol-3-yl) methyl) -1,3,4-oxadiazol-2-ol (12). A mixture of 2- (5-methoxy-1H-30 indole-3-yl) acetohydrazide (86 mg, 0.4 mmol), CDI (76 mg, 0.47 mmol) and triethylamine (0.11 ml, 0.8 mmol) in THF is heated at 100 ° C for 15 min. The solvent was evaporated and the residue was re-suspended in a small amount of water (2 ml), which was placed at pH 12-13 with NaOH (conc.) And filtered. The filtrate was collected and acidified with HCl (conc.), Precipitating 12 as a pearly white solid, which was isolated by filtration (72 mg, 73%). 1H NMR (300 35

MHz, DMSO-d6) δ 12.12 - 12.01 (s, 1H), 10.90 - 10.84 (s, 1H), 7.28 - 7.25 (d, J = 6.1 Hz, 1H), 7.25 - 7.24 (s, 1H), 7.01 - 6.99 (d, J = 2.3 Hz, 1H), 6.77 - 6.72 (dd, J = 8.8, 2.4 Hz, 1H), 4.01 - 3.94 (s, 2H), 3.74 - 3.70 (s, 3H). 13C NMR (75 MHz, DMSO-d6) δ 156.46, 155.07, 153.18, 131.24, 127.03, 124.78, 112.22, 111.27, 105.87, 100.11, 55.30, 22.54. HPLC-MS (m / z) [MH +] 246. 5

5- (2- (1H-Indol-3-yl) ethyl) -1,3,4-oxadiazol-2-ol (13). Following the procedure of the previous product, from 3- (1H-indole-3-yl) propanhydrazide (56 mg, 0.27 mmol), 13 (22 mg, 35%) was obtained as a pearly white solid. 1H NMR (300 MHz, CDCl3) δ 8.98 - 8.94 (s, 1H), 8.07 - 8.00 (s, 1H), 7.61 - 7.56 (d, J = 7.7 Hz, 1H), 7.39 - 7.35 (d, J = 8.7 Hz, 1H), 7.25 - 10 7.19 (t, J = 7.5 Hz, 1H), 7.17 - 7.11 (d, J = 8.7 Hz, 1H), 7.04 - 7.02 (s, 1H), 3.23 - 3.14 (t, J = 7.5 Hz, 2H), 3.00 - 2.93 (t, J = 7.5 Hz, 2H). 13C NMR (75 MHz, DMSO-d6) δ 158.14, 156.24, 136.52, 127.10, 124.35, 121.51, 118.94, 118.63, 111.87, 107.30, 27.38, 19.20. HPLC-MS (m / z) [MH +] 230.

5 - ((5-Methoxy-1H-indol-3-yl) methyl) -1,3,4-oxadiazol-2-thiol (14). A mixture of 2- (5-methoxy-15 1H-indol-3-yl) acetohydrazide (commercial) (83 mg, 0.37 mmol), KOH (70 mg, 1.24 mmol) and an excess of carbon disulfide (1.35 mL, 38 mmol) in EtOH was heated at 155 ° C for 10 min under microwave irradiation. The solvent and excess carbon disulfide were evaporated under reduced pressure and the residue was resuspended in water. The solution was acidified with conc. HCl, precipitating 14 as a yellow solid that was filtered off 20 (91 mg, 95%) .1H NMR (300 MHz, DMSO-d6) δ 14.37-14.29 (s, 1H), 10.95 - 10.88 (s, 1H), 7.29 - 7.24 (d, J = 11.8 Hz, 1H), 7.28—7.27 (s, 1H), 7.02 - 6.99 (d, J = 2.3 Hz, 1H), 6.77 - 6.72 (dd, J = 8.8, 2.4 Hz, 1H), 4.18-4.15 (s, 2H), 3.74-3.72 (s, 3H). 13C NMR (75 MHz, DMSO-d6) δ 177.73, 163.44, 153.25, 131.23, 126.94, 125.01, 112.28, 111.38, 105.39, 100.08, 55.31, 21.74. HPLC-MS (m / z) [MH +] 262. 25

5- (2- (1H-Indol-3-yl) ethyl) -1,3,4-oxadiazol-2-thiol (15). Following the above procedure, from 3- (1H-indole-3-yl) propanohydrazide (67 mg, 0.33 mmol) 15 (74 mg, 97%) was obtained as an orange solid. 1H NMR (300 MHz, DMSO-d6) δ 14.31 - 14.23 (s, 1H), 10.88 - 10.80 (s, 1H), 7.53 - 7.48 (d, J = 7.7 Hz, 1H), 7.35 - 7.30 (d, J = 7.4 Hz, 1H), 7.16 - 7.12 (d, 30 J = 2.2 Hz, 1H), 7.10 - 7.02 (t, J = 7.5 Hz, 1H), 7.00 - 6.93 (t, J = 7.4 Hz, 1H), 3.08-3.07 (s, 4H). 13C NMR (75 MHz, DMSO-d6) δ 177.76, 163.43, 136.15, 126.55, 124.46, 121.35, 118.82, 118.10, 111.63, 105.70, 26.9, 19.91. HPLC-MS (m / z) [MH +] 246.

5 - ((5-Methoxy-1H-indole-3-yl) methyl) -4-methyl-4H-1,2,4-triazol-3-ol (16). On a solution of 2- (5-methoxy-1H-indole-3-yl) acetohydrazide (commercial) (66 mg, 0.3 mmol) in a mixture of water (2.5 mL) and acetic acid (6 drops) was added isocyanate methyl (0.60 mL, 0.97 mmol) and the mixture was stirred for 1.5 h at room temperature. The solvent was evaporated under reduced pressure and the residue was dissolved in EtOH (3 mL), then treated with 2M NaOH (2.25 mL). The mixture is heated under microwave irradiation at 100 ° C for 15 min. The solvent is evaporated and the crude is suspended in water (1 mL), brought to pH 2 by the addition of conc. HCl, precipitating 16 as a white solid that is filtered off (58 mg, 75%). 1H NMR (300 MHz, DMSO-d6) δ 11.41 (s, 1H), 10.82 (s, 1H), 7.25 (d, J = 8.8 Hz, 1H), 7.20 (d, J = 2.3 Hz, 1H), 7.01 (d, J = 2.4 Hz, 1H), 6.74 (dd, J = 8.8, 2.4 10 Hz, 1H), 3.95 (s, 2H), 3.72 (s, 3H), 2.98 (s, 3H). 13C NMR (75 MHz, DMSO-d6) δ 155.65, 153.43, 147.20, 131.77, 127.50, 124.77, 112.51, 111.54, 107.40, 100.68, 55.65, 26.88, 22.86. HPLC-MS (m / z) [MH +] 259.

5 - ((1H-Indol-3-yl) methyl) -4-methyl-4H-1,2,4-triazol-3-ol (17). From 2- (1H-indole-3-15 yl) acetohydrazide (19 mg, 0.1 mmol), according to the above procedure, 17 was obtained as a white crystalline solid (14 mg, 62%). 1H NMR (300 MHz, DMSO-d6) δ 11.39 (s, 1H), 10.97 (s, 1H), 7.49 (d, J = 7.9 Hz, 1H), 7.34 (dt, J = 8.1, 0.9 Hz, 1H) , 7.25 (d, J = 2.4 Hz, 1H), 7.07 (ddd, J = 8.2, 7.1, 1.2 Hz, 1H), 6.96 (ddd, J = 8.0, 7.0, 1.1 Hz, 1H), 3.97 (s, 2H ), 2.96 (s, 3H). 13C NMR (126 MHz, DMSO-d6) δ 155.71, 147.25, 136.71, 127.21, 20 124.26, 121.65, 119.00, 118.77, 111.96, 107.82, 26.97, 22.94. HPLC-MS (m / z) [MH +] 229.

4-Ethyl-5 - ((5-methoxy-1H-indole-3-yl) methyl) -4H-1,2,4-triazol-3-thiol (18). To a solution of 2- (5-methoxy-1H-indol-3-yl) acetohydrazide (74 mg, 0.33 mmol) in tetrahydrofuran (THF, 10 mL) was added ethyl thioisocyanate (0.035 mL, 0.4 mmol) and the mixture It was stirred for 18-25 hours at room temperature. The intermediate acylthiosemicarbazide was filtered off (53 mg, 60%). Following the above procedure for cyclization (see synthesis of 16), from 40 mg (0.13 mmol) of this intermediate, 18 (30 mg, 80%) was obtained as a yellow solid. 1H NMR (300 MHz, DMSO-d6) δ 13.51 (s, 1H), 10.88 (s, 1H), 7.27 (d, J = 3.2 Hz, 1H), 7.25 (d, J = 3.2 Hz, 1H), 6.99 (d, J = 2.3 Hz, 1H), 6.74 (dd, J = 8.8, 2.4 Hz, 1H), 4.16 30 (s, 2H), 3.90 (q, J = 7.0 Hz, 2H), 3.72 (s, 3H ), 0.94 (t, J = 7.1 Hz, 3H). 13C NMR (75 MHz, DMSO-d6) δ 166.63, 153.49, 151.61, 131.74, 127.43, 125.08, 112.60, 111.58, 107.29, 100.64, 55.65, 38.62, 22.22, 13.23. HPLC-MS (m / z) [MH +] 289.

5 - ((1H-Indol-3-yl) methyl) -4-ethyl-4H-1,2,4-triazol-3-thiol (19). From 2- (1H-indole-3-yl) acetohydrazide (19 mg, 0.1 mmol), according to the procedure described for 16, 19 was obtained as a pearl white solid (16 mg, 62%). 1H NMR (300 MHz, DMSO-d6) δ 11.06 (s, 1H), 7.47 (d, J = 7.7 Hz, 1H), 7.35 (d, J = 8.1 Hz, 1H), 7.31 (d, J = 2.3 Hz , 1H), 7.07 (t, J = 7.5 Hz, 1H), 6.95 (t, J = 7.5 Hz, 1H), 4.18 (s, 2H), 3.89 (q, J = 7.0 Hz, 2H), 0.90 (t , J = 5 7.1 Hz, 3H). 13C NMR (126 MHz, DMSO-d6) δ 166.65, 151.68, 136.68, 127.12, 124.60, 121.73, 119.13, 118.71, 112.04, 107.67, 38.71, 22.33, 13.31. HPLC-MS (m / z) [MH +] 259.

2. Biological evaluation

 10

2.1. Melatonin MT1 and MT2 receptor binding assays and study of intrinsic activity

The products of the invention were evaluated against human melatonin receptors of type MT1 and MT2 transfected in HEK and CHO cell lines, using 2-15 [125I] iodomelatonin as radioligand and following described protocols (Ettaoussi, M .; Sabaouni, A. ; Rami, M .; Boutin, JA; Delagrange, P .; Renard, P .; Spedding, M .; Caignard, D.-H .; Berthelot, P .; Yous, S. Design, synthesis and pharmacological evaluation of new series of naphthalenic analogues as melatoninergic (MT1 / MT2) and serotoninergic 5-HT2C dual ligands (I). Eur. J. Med. Chem. 2012, 49, 310-323; Audinot, V .; Mailliet, F .; Lahaye- 20 Brasseur, C .; Bonnaud, A .; Le Gall, A .; Amosse, C .; Dromaint, S .; Rodriguez, M .; Nagel, N .; Galizzi, JP; Malpaux, B .; Guillaumet, G. ; Lesieur, D .; Lefoulon, F .; Renard, P .; Delagrange, P .; Boutin, JA New selective ligands of human cloned melatonin MT1 and MT2 receptors. Naunyn-Schmiedeberg's Arch. Pharmacol. 2003, 367, 553-561 ).

 25

HEK and CHO cell lines with stable expression of human MT1 and MT2 type melatonin receptors were cultured in DMEM medium (Dulbecco's modified Eagle's medium) supplemented with 10% fetal bovine serum, 2 mM glutamine, 100 IU / mL penicillin and 100 mg / mL streptomycin. The cells were grown to confluence at 37 ° C (95% O2 / 5% CO2), suspended in PBS containing 2 mM of 30 EDTA and centrifuged at 1000 x g for 5 min at 4 ° C. The resulting sediment was suspended in 5 mM Tris buffer (pH 7.5), containing 2 mM EDTA, and homogenized. The homogenate was then centrifuged (95,000 x g, 30 min, 4 ° C) and the resulting sediment was suspended in 75 mM Tris buffer (pH 7.5) with 12.5 mM MgCl2 and 2 mM of

EDTA Aliquots of the membrane preparations were stored at -80 ° C until use.

Binding assays were performed by adding membrane preparations of transfected cells of the HEK or CHO type diluted in Tris-HCl buffer (50 mM, pH 7.4, 5 with 5 mM MgCl2) at 2- [125 I] iodomelatonin ( 25 or 200 pM for MT1 and MT2 receptors, respectively, expressed in HEK cells or 20 pM for MT1 and MT2 receptors expressed in CHO cells) and the compound to be tested. Non-specific binding was defined in the presence of 1 µM of melatonin. After 120 min incubation at 37 ° C, the reaction was stopped by rapid filtration through GF / B filters previously soaked with a 0.5% polyethyleneimine solution (v / v). The filters were washed three times with 1 mL of Tris-HCl buffer (50 mM, pH 7.4) cooled with ice. Data from the dose-response curves (seven concentrations in duplicate) were analyzed using the PRISM program (Graph Pad Software Inc., San Diego, CA) to calculate the IC50 (inhibitory concentration 50). The results are found in Table 1 and are expressed as Ki = IC50 / 1 + ([L] / KD), where [L] is the concentration of radioligand used in the assay and KD, the radioligand dissociation constant.

Intrinsic activity assays were performed using [35S] GTPS (5'-O- [gamma-thio] guanosine triphosphate). The preparations of transfected CHO cell membranes 20 expressing the MT1 and MT2 subtypes, together with the compound tested, were diluted in HEPES buffer (20mM, pH 7.4, 100 mM NaCl, 3 M GDP, 3 mM MgCl2, and 20 g / mL of saponin). To measure the agonist activity, a 0.2 nM solution of [35S] GTPS was added to the preparation containing the membranes (20 g / mL) and the product to be evaluated and the whole was incubated for 1 hour at room temperature. To evaluate the antagonistic activity, the membranes were previously incubated with both melatonin (3 nM) and with the product to be tested for 30 min before the addition of [35S] GTPS. Non-specific binding was defined using cold GTPS (10 M). All reactions were stopped by rapid filtration through GF / B filters, followed by three successive washes with ice-cold buffer. The usual levels of [35S] GTPS 30 (expressed in dpm) at the junction with the CHO-MT2 membranes were: 2000 for basal activity, 8000 in the presence of 1 M melatonin and 180 in the presence of 10 mM GTP S that defines the non-specific union. Data from the dose-response curves (seven concentrations in duplicate) were analyzed using the PRISM program (Graph Pad Software Inc., San Diego, CA) to calculate the EC50 (50% effective concentration) and Emax 35

(maximum effect, expressed as the percentage in relation to that observed with 1 µM of melatonin defined as 100%) for agonists. The potency of the antagonists were expressed as KB = IC50 / 1 + ([Aug] / EC50 ago), where IC50 is the concentration of antagonist that provides 50% inhibition of the binding of [35S] GTPS in the presence of A fixed concentration of melatonin ([Aug]) and EC50 ago is the EC50 of the agonist when it was tested alone. The EImax value (maximum inhibitory effect) was expressed as the percentage of the effect observed with melatonin, 30 nM or 3nM ([ago]) for the hMT1 and hMT2 receptors, respectively. When EImax is greater than 80%, the product is an agonist; when it is less than 20%, antagonist; and between these two figures, partial agonist. The results of the intrinsic activity of a selection of the products of the invention are found in table 2.

Table 1. Binding data to MT1 and MT2 melatonin receptors (Ki, molar) of the products of the invention.

 Comp.

 MT1 MT2

 one

 1.7 10-8 4.9 10-9

 2

 2.5 10-9 4.5 10-10

 3

 1.4 10-8 3.8 10-9

 4

 5.0 10-9 1.0 10-9

 5

 > 10-5> 10-5

 6

 > 10-5> 10-5

 7

 > 10-5 2.8 10-7

 8

 > 10-5 5.0 10-7

 9

 1.7 10-7 4.4 10-8

 10

 > 10-5> 10-5

 eleven

 7.0 10-7 1.9 10-7

 12

 > 10-5 1.6 10-7

 13

 > 10-5> 10-5

 14

 > 10-5 5.3 10-7

 fifteen

 > 10-5> 10-5

 16

 > 10-5 5.6 10-7

 17

 > 10-5> 10-5

 18

 > 10-5 2.1 10-7

 19

 > 10-5> 10-5

Table 2. Intrinsic activity of the products of the invention on MT1 and MT2 melatonin receptors

 MT1 MT2

 Comp

 EC50 (M) EImax (%) Character EC50 (M) EImax (%) Character

 3

 3.0 10-7 67 Partial Agonist 8.0 10-8 82 Agonist

 4

 4.0 10-8 100 Agonist 3.0 10-9 99 Agonist

 7

 nd nd nd 1.0 10-6 23 Partial agonist

 8

 nd nd nd 5.0 10-7 32 Partial agonist

 9

 7.0 10-7 16 Antagonist 3.0 10-7 48 Partial Agonist

 eleven

 1.0 10-6 19 Antagonist 9.0 10-7 32 Partial Agonist

2.2. Determination of antioxidant properties

 5

The ability of the products of the invention to capture oxygen free radicals, as a measure of their antioxidant properties, was evaluated following the ORAC-FL method (Oxygen Radical Absorbance Capacity Assay by Fluorescence), described by Ou et al. (Ou, B .; Hampsch-Woodill, M .; Prior, RL Development and validation of an improved oxygen radical absorbance capacity assay using fluorescein as the fluorescent probe. J. 10 Agric. Food Chem. 2001, 49, 4619-4626) and partially modified by Dávalos et al. (Dávalos, A .; Gómez-Cordovés, C .; Bartolomé, B. Extending applicability of the oxygen radical absorbance capacity (ORAC-fluorescein) assay. J. Agric. Food Chem. 2004, 52, 48-54).

 fifteen

The experiment was carried out on a Polarstar Galaxy fluorometer (BMG Labtechnologies GmbH, Offenburg, Germany) with 96-well plate reader, with excitation and emission filters at 485-P and 520-P, respectively. The equipment was controlled by the Fluorostar Galaxy software (version 4.11-0) for fluorescence measurement. Dihydrochloride

2,2'-azobis- (amidinopropane) (AAPH), (±) -6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox) and fluorescein (FL) were purchased from Sigma -Aldrich. The reaction was carried out in phosphate buffer (75 mM, pH 7.4), with a total volume of 200 µL. Different solutions of the product to be tested (20 μL) and FL (120 μL, final concentration of 70 mM) were placed in a black 96-well microplate (Nunc, 96F untreated). The mixture was pre-incubated for 15 min at 37 ° C, and then a solution of AAPH (60 µL, final concentration of 12 mM) was quickly added using a multichannel pipette. The microplate was immediately placed in the reader and fluorescence was recorded every minute for 80 min, automatically shaking the microplate before each reading. Each of the products tested was measured in eight different concentrations (0.1-1 μM). In each of the experiments, four wells were used for the blank (FL and AAPH in phosphate buffer, without sample) and eight calibration solutions using trolox (1-8 μM). All reaction mixtures were prepared in duplicate and each product was measured in at least three independent tests. Fluorescence data was exported from the Galaxy Fluostar software to an Excel sheet for later calculations. The curves of fluorescence versus time were normalized with the blank, then the area under the curve (AUC) of each sample was calculated. For each of the products tested, the graphic representation of the AUC versus the product concentration provided straight lines, which were adjusted by linear regression.

 twenty

The ORAC-FL values of the products of the invention are listed in Table 3 and are expressed as equivalents of trolox (μmol of trolox / μmol of product) on a relative scale, in which the trolox was assigned the value of the unit. Melatonin was also evaluated as a positive standard, giving an ORAC-FL value of 2.3 equiv. of trolox, in accordance with the value of 2.0 equiv. of trolox, previously described by Sofic et 25 al. (Sofic, E .; Rimpapa, Z .; Kundurovic, Z .; Sapcanin, A .; Tahirovic, I .; Rustembegovic, A .; Cao, G. Antioxidant capacity of the neurohormone melatonin. J. Neural Transm. 2005, 112 , 349-358).

As can be seen in Table 3, the products of the invention have good antioxidant properties, close to melatonin and up to 2.28 times more potent than trolox, the aromatic and active fragment of vitamin E and responsible for the capture of free radicals. . Therefore, the products of the invention behave as useful antioxidants to counteract the oxidative stress caused by an excess of free radicals.

 35

Table 3. Free radical capture (ORAC-FL), inhibition of human acetylcholinesterase (h-AChE) and human butyrylcholinesterase (h-BuChE) data.

 Comp.

 ORAC-FL (μmol trolox / μmol product) to h-AChE (IC50, µM) b h-BuChE (IC50, µM) b

 one

 1.65 ± 0.08 6.95 ± 0.34> 10

 2

 2.05 ± 0.31 7.59 ± 0.30> 10

 3

 1.63 ± 0.09> 10> 10

 4

 1.99 ± 0.12> 10> 10

 5

 1.62 ± 0.23> 10> 10

 6

 1.78 ± 0.06> 10> 10

 10

 1.61 ± 0.04> 10> 10

 eleven

 1.66 ± 0.08> 10> 10

 12

 1.97 ± 0.11 6.26 ± 0.20> 10

 13

 2.06 ± 0.22 6.99 ± 0.26> 10

 14

 1.94 ± 0.07 5.07 ± 0.23> 10

 fifteen

 2.28 ± 0.22 6.24 ± 0.27> 10

 16

 1.78 ± 0.02 6.05 ± 0.41> 10

 17

 1.52 ± 0.03 4.86 ± 0.24> 10

 18

 1.55 ± 0.01 6.58 ± 0.33> 10

 19

 1.29 ± 0.19 5.30 ± 0.41> 10

 Melatonin

 2.30 ± 0.10 nd nd

 Tacrina

 nd 0.04 ± 0.002 0.010 ± 0.004

aMedia of 3 independent experiments ± standard deviation. bMedia of 3 independent 5 experiments ± SEM.

2.3. Inhibition of human acetyl- and butyrylcholinesterase

The compounds of the invention were evaluated as inhibitors of human acetyl- and 10-butyrylcholinesterase (h-AChE and h-BuChE). Enzyme inhibition was measured using the Ellman method (Ellman, GL; Courtney, KD; Andres, V., Jr .; Feather-Stone, RM A new and rapid colorimetric determination of acetylcholinesterase activity. Biochem. Pharmacol. 1961 , 7, 88-95). The test solution was formed by

0.1 M phosphate buffer at pH = 8, 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) 400 μM, the enzymes h-AChE (recombinant human acetylcholinesterase, Sigma Chemical Co.) 0.05 ud / mL or h-BuChE ( human serum butyrylcholinesterase, Sigma Chemical Co.) 0.024 unit / mL and 800 μM of acetylthiocholine iodide or 500 μM of butyrylthiocholine respectively, as substrates for enzymatic reactions. The compounds to be evaluated were pre-incubated with the enzyme for 5 minutes at 30 ° C, the substrate was added and the absorbance changes at 412 nm were measured every 5 minutes on a Multiskan Spectrum UV / VIS spectrometer. The reaction rates were compared and the percentages of inhibition due to the presence of the compounds being analyzed were calculated. The enzymatic activity at each concentration of compound is expressed as a percentage of activity with respect to the control in the absence of compound. IC50 is defined as the concentration of compound that inhibits 50% enzyme activity with respect to the control of untreated enzyme. The results are found in table 3, expressed as the average of three independent experiments ± standard deviation.

 fifteen

The results of human cholinesterase inhibition indicate that most of the compounds evaluated are selective h-AChE inhibitors with inhibitory concentrations in the micromolar order. Therefore, they are able to moderately increase the levels of the neurotransmitter acetylcholine and improve the cognitive abilities of patients. twenty

2.4. Binding assays on serotonin receptors

Several compounds of the invention were tested against the following subtypes of human serotonin receptors 5-HT1A, 5-HT1B, 5-HT1D, 5-HT1E, 5-HT2A, 5-HT2B, 5-HT2C, 25 5-HT3, 5-HT5A, 5-HT6 and 5-HT7 at the University of North Carolina at Chapel Hill USA (National Institute of Mental Health's Psychoactive Drug Screening Program), where the experimental protocols described in http://pdsp.med were followed. unc.edu/.

Of the products tested, 12 and 15 were found to be ligands of the human recombinant 5-HT1A 30 receptor with Ki inhibition constants of 7768 and 957 nanomolar, respectively, using as radioligand [3H] 8-OH-DPAT. In the rest of the receptors tested no binding was observed using a product concentration of 10 micromolar, indicating a clear selectivity for subtype 5-HT1A.

 35

The affinity of compound 11 for the 5-HT1A human receptor agonist site in HEK-293 transfected cells was also evaluated, using [3H] 8-OH-DPAT as radioligand (Cerep, www.cerep.com/). At a concentration of 10 micromolar, product 11 inhibited radioligand binding in 94% and was able to cause a 38% response compared to the reference product, serotonin. In a similar test on the 5-HT2C receptor, compound 11 demonstrated no stimulation of any significant response to said concentration.

2.5 In vitro studies of neurogenesis on neural stem cells of adult rats 10

In vitro neurogenesis studies were performed using neural stem cell cultures that were initiated from the two main neurogenic areas: the subventricular zone (SVZ) and the subgranular zone of the dentate gyrus of the adult Wistar rat hippocampus. For this, the brain was dissected, obtaining the SVZ and the hippocampus, which were divided into DMEM (Dubecco's Modified Eagle's Medium) medium (Morales-García, JA; Luna-Medina, R .; Alfaro-Cervello, C .; Cortes- Canteli, M .; Santos, A .; García-Verdugo, JM; Pérez-Castillo, A. Peroxisome proliferator-activated receptor gamma ligands regulate neural stem cell proliferation and differentiation in vitro and in vivo. Glia 2011, 59, 293-307 ). The cells obtained were cultured by established methods to achieve optimal proliferation in DMEM / F12 medium (1: 1, Invitrogen) and were supplemented with 10 ng / mL epidermal growth factor (EGF, Peprotech, London, UK), 10 ng / mL fibroblast growth factor (FGF, Peprotech) and B27 medium (Gibco) (Ferron, SR; Andreu-Agullo, C .; Mira, H .; Sánchez, P .; Marqués-Torrejón, MA; Farinas , I. A combined ex / in vivo assay to detect effects of exogenously added factors in neural stem 25 cells. Nat. Protoc. 2007, 2, 849-859). Under these conditions the cells proliferate in flotation and form spherical groups called neurospheres (NS). After 3 days in culture the NS were treated with products 4, 11 and 14 at a concentration of 10 micromolar. To determine the ability of the compounds to induce differentiation, the neurospheres treated for 10 days on flotation were glued on a substrate (covers treated with 100 30 µg / mL poly-L-lysine) and treated for 24, 48 and 96 hours more in the absence of exogenous and serum growth factors (Morales-García, JA; Luna-Medina, R .; Alonso-Gil, S .; Sanz-Sancristóbal, M .; Palomo, V .; Gil, C. ; Santos, A .; Martínez, A .; Pérez-Castillo, A. Glycogen synthase kinase 3 inhibition promotes adult hippocampal neurogenesis in vitro and in vivo. ACS Chem. Neurosci. 2012, 3, 963-971). After treatment, the crystals with the 35

Neurospheres were processed for immunocytochemistry with two types of neuronal markers associated with neurogenesis: anti-beta-tubulin antibody (clone Tuj1), related to early stages of neurogenesis and MAP-2 (microtubule-associated protein 2), neuronal maturity marker. The baseline values of the experiment were obtained under the same conditions, in the absence of product. Melatonin 5 (endogenous ligand of melatoninergic receptors) and luzindole (antagonist of melatoninergic receptors) were used as controls. The images were obtained using a Nikon 90i fluorescence microscope, coupled to a Qi digital camera. The microscope configuration was adjusted to produce the optimal signal-to-noise ratio.

 10

Figures 1 and 2 show the neurogenic effect of the products of the invention on neuronal stem cell cultures of adult Wistar rats treated with vehicle (basal), melatonin (endogenous ligand of MT receptors), luzindole (antagonist of MT receptors) , 4, 11 and 14 all of them at a concentration of 10 micromolar. Full neurosphere images are shown, as well as enlargements that show the inside (center of the neurosphere) and the outside of them (migration zone). Two types of neuronal markers were used: anti-beta-tubulin antibody and MAP-2, respectively associated with early neurogenesis and neuronal maturity. DAPI staining was used as a nuclear marker. All the products evaluated were able to increase the differentiation of neurospheres (Tuj1 marker, early neurogenesis) (Figure 1). In addition, 11 and 14 are 20 potent neurogenesis inducers at all times studied and with both markers (TuJ and MAP-2), being more potent than melatonin itself (Figure 2).

Claims (23)

1.- Compound of general formula (I):  5 its pharmaceutically acceptable salts or solvates, where R1 is H, (C1-C6) alkyl or (C1-C6) alkoxy n = 1-6 10 X is O or N, with the particularity that when X is O, Y is N, L1 is absent and L2 is alkenyl or alkynyl Y is O or N, with the particularity that when Y is O, X is N and L1 and L2 give rise to a 5-membered aromatic heterocycle comprising up to 3 heteroatoms and which may be substituted by hydrogen, (C1-) alkyl C6), hydroxyl, (C1-C6) alkoxy, thiol or mercaptoalkyl (C1-C6) L2 is alkenyl, alkynyl (when X is O) or together with L1 forms a 20-membered aromatic heterocycle comprising up to 3 heteroatoms and which may be substituted by hydrogen, (C1-C6) alkyl, hydroxyl, (C1-C6) alkoxy ), thiol or mercaptoalkyl (C1-C6) 2. Compound according to claim 1 and the general formula (I), wherein, X is O, Y is N, n is equal to 1 or 2 and L2 is allyl or prop-2-in-1-yl, according to the formula (II): 25 Formula (II) 3. Compound according to claim 1 and the general formula (I), wherein X is N, Y is O, n is equal to 1 or 2 and L1 and L2 form a 5-membered aromatic heterocycle and two heteroatoms 5 substituted with a methyl, according to formula (III): Formula (III) 4. Compound according to claim 1 and the general formula (I), wherein X is N, Y is O, n is 10 equal to 1 or 2 and L1 and L2 form a 5-membered and three heteroatom aromatic heterocycle, substituted with a methyl according to formula (IV): Formula (IV)  fifteen 5. A compound according to claim 1 and the general formula (I), wherein X is N, Y is O, n is equal to 1 or 2, and L1 and L2 form a 5-membered and three heteroatom aromatic heterocycle, substituted with an R2 radical that is methyl, hydroxyl or thiol according to formula (V): Formula (V) 6. Compound according to claim 1 and the general formula (I), wherein X is N, Y is N, n is equal to 1 or 2, and L1 and L2 form a 5-membered and three heteroatom aromatic heterocycle, substituted with an R2 radical that is hydroxyl or thiol and an R3 radical that is alkyl according to formula (VI): Formula (VI)  10 7. A compound according to claim 1 wherein said compound is selected from the following group: • N-Alyl-2- (5-methoxy-1H-indole-3-yl) acetamide (1) • N-Alyl-3- (5-methoxy-1H-indole-3-yl) propanamide (2) 15 • 2- (5-Methoxy-1H-indol-3-yl) -N- (prop-2-in-1-yl) acetamide (3) • 3- (5-Methoxy-1H-indol-3-yl) -N- (prop-2-in-1-yl) propanamide (4) • 2- (2- (1H-Indol-3-yl) ethyl) -5-methylxazole (5) • 2 - ((1H-Indol-3-yl) methyl) -5-methylxazole (6) • 2 - ((5-Methoxy-1H-indol-3-yl) methyl) -5-methylxazole (7) 20 • 2- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -5-methylxazole (8) • 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -3-methyl-1,2,4-oxadiazole (9) • 5- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -3-methyl-1,2,4-oxadiazole (10) • 2- (2- (5-Methoxy-1H-indol-3-yl) ethyl) -5-methyl-1,3,4-oxadiazole (11) • 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -1,3,4-oxadiazol-2-ol (12) 25 • 5- (2- (1H-Indol-3-yl) ethyl) -1,3,4-oxadiazol-2-ol (13) • 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -1,3,4-oxadiazol-2-thiol (14) • 5- (2- (1H-Indol-3-yl) ethyl) -1,3,4-oxadiazol-2-thiol (15) • 5 - ((5-Methoxy-1H-indol-3-yl) methyl) -4-methyl-4H-1,2,4-triazol-3-ol (16) • 5 - ((1H-Indol-3-yl) methyl) -4-methyl-4H-1,2,4-triazol-3-ol (17) 5 • 4-Ethyl-5 - ((5-methoxy-1H-indol-3-yl) methyl) -4H-1,2,4-triazol-3-thiol (18) • 5 - ((1H-Indol-3-yl) methyl) -4-ethyl-4H-1,2,4-triazol-3-thiol (19) or an isomer, a solvate, or a pharmaceutically acceptable salt thereof.  10 8. Method for obtaining a compound of general formula (II) according to claims 1 and 2, consisting of the treatment of the corresponding carboxylic acid derived from 1H-indole-3-yl in dry acetonitrile with allylamine or propargilamine in the presence of 1 , 1'-carbonyldiimidazole (CDI) and 4- (dimethylamino) pyridine (DMAP).  fifteen 9. Process for obtaining a compound of general formula (III) according to claims 1 and 3, consisting in the treatment of the corresponding N- (prop-2-inyl) alkylamide derived from 1H-indole-3-yl in dichloromethane dried with gold chloride (III). 10. Process for obtaining a compound of general formula (IV) according to claims 1 and 4, consisting of the reaction of an alkyl ester of the corresponding carboxylic acid derived from 1H-indole-3-yl with acetamidoxime in the presence of hydride sodium 11. Process for obtaining a compound of general formula (V) according to claims 1 and 5, consisting of the reaction of the corresponding carboxylic acid derived from 1H-indole-3-yl in dry acetonitrile with the corresponding substituted hydrazide in the presence 1,1'-carbonyldiimidazole (CDI) and 4- (dimethylamino) pyridine (DMAP), followed by treatment with phosphorus oxychloride.   30 12. Process for obtaining a compound of general formula (VI) according to claims 1 and 6, consisting of reacting the hydrazide of the corresponding carboxylic acid derived from 1H-indole-3-yl with an isocyanate or substituted isothiocyanate in a mixture of acetic acid and water, followed by treatment with sodium hydroxide in ethanol.  35 13. Pharmaceutical composition comprising a compound of formula (I) to (VI) according to any of claims 1 to 7. 14. Composition according to claim 13 further comprising another active ingredient.  5 15. Pharmaceutical composition according to claims 13 and 14 suitable for oral administration. 16. Use of melatonin-based neurogenic compounds according to any one of claims 1 to 7 in the preparation of a medicament or a pharmaceutical composition for the treatment of diseases of the nervous system that are selected from neurodegenerative diseases, cognitive disorders, psychiatric diseases or disorders, traumas or cell injuries, neurological conditions and diseases or disorders related to the circadian cycle.  fifteen 17. Use according to claim 16, wherein the neurodegenerative disease is selected from Alzheimer's disease, Creutzfeld-Jacob disease, Parkinson's disease, systemic amyloidosis, amyotrophic lateral sclerosis, degenerative retinal disease, cerebral palsy or a combination from the same.  twenty 18. Use according to claim 16, wherein the cognitive disorder is selected from memory impairment, memory loss separated from dementia, mild cognitive impairment, age-related cognitive decline, memory loss due to attention deficit, cognitive impairment such as consequence of the use of general anesthetics, chemotherapy or radiotherapy, cognitive impairment associated with post-surgical trauma or therapeutic intervention, cognitive decline associated with Alzheimer's disease or with epilepsy, senile dementia, vascular dementia, delirium or a combination of same. 19. Use according to claim 16, wherein the disease or psychiatric disorder is selected from depression, major depression, neurotic depression, depression caused by drug or alcohol use, post-traumatic depression, postpartum depression, anxiety, obsessive-compulsive disorder, bipolar disorder, social phobia, seasonal mood disorder or a combination thereof. 20. Use according to claim 16, wherein the trauma or cell injury is selected from trauma or neurological injury, brain or spinal cord surgery, retinal injury, epilepsy-related injuries, brain or spinal cord injuries in relation to with the treatment of cancer, brain or spinal cord injuries related to infections, inflammatory processes, environmental toxins, ischemic episodes, or a combination thereof. 21. Use according to claim 16, wherein the neurological condition is selected from learning disorder, autism, attention deficit disorder, narcolepsy, sleep disorder, epilepsy, temporal lobe epilepsy or a combination thereof. 10 22. Use according to claim 16, wherein the disease or disorder related to the circadian cycle is selected from sleep disorders, daytime fatigue, loss of mental efficacy, weakness and irritability and transoceanic syndrome or a combination thereof. fifteen 23. Use of a compound according to any one of claims 1 to 7 as a reagent in biological tests.