4-aromatic alkynyl substituted thieno [2, 3-c] picolinamide compound as well as preparation method and application thereof

Abstract

The invention discloses a 4-aromatic alkynyl substituted thieno [2, 3-c] picolinamide compound as well as a preparation method and application of the 4-aromatic alkynyl substituted thieno [2, 3-c] picolinamide compound. The structural general formula of the 4-aromatic alkynyl substituted thieno [2, 3-c] picolinamide compound is as shown in the following formula I: # imgabs0. The 4-aromatic alkynyl substituted thieno [2, 3-c] picolinamide compound disclosed by the invention is simple in preparation method, has targeting activity on a metabolic glutamate receptor fifth subtype (mGluR5), and has a potential effect of treating diseases related to the target.

Description

Technical Field

[0001] The present invention belongs to the field of pharmaceutical chemistry and pharmacotherapy, and specifically relates to a 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compound and a preparation method thereof, and use thereof in treating diseases associated with the fifth subtype of metabotropic glutamate receptor (mGluR5). Background Art

[0002] Glutamate (Glu) is the most important excitatory neurotransmitter in the central nervous system of mammals and plays an important role in maintaining the normal function of the central nervous system. Under normal physiological conditions, glutamate participates in the conduction of excitability and regulates various physiological functions of the body through glutamate receptors; under pathological conditions, the massive release and accumulation of glutamate in the nervous system is the pathological basis for a variety of nerve cell damage and central neuron death in neurodegenerative diseases such as Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease and Huntington's disease. Studies have reported that elevated glutamate levels in central and peripheral blood are closely related to depression. After chronic stress stimulation, a large amount of glutamate is released from cells and selectively acts on hippocampal neurons. The excitatory amino acid transmitters accumulated outside the cells continuously and strongly act on cell membrane receptors, increasing the permeability of the cell membrane and causing extracellular Ca 2+ The massive influx of Ca 2+ Concentration overload causes neuronal damage and eventually leads to a series of neurological diseases ending with nerve cell death. An animal experiment showed that the glutamate receptor antagonist CGP-37849 can reduce the immobility time of rats during forced swimming and produce an antidepressant effect.

[0003] Glutamate receptors (GluRs) are mainly divided into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs) according to their ligands, downstream signal transduction mechanisms and molecular homology. Ionotropic glutamate receptor antagonists have achieved certain therapeutic effects in animal models by directly blocking the postsynaptic effects of glutamate, but they also block normal excitatory transmission and produce serious side effects, such as synaptic dysfunction, dizziness, fatigue, etc., which limits the clinical application of such compounds. mGluRs inhibit the release of glutamate through presynaptic mechanisms, reducing the toxic side effects of iGluRs antagonists, and are expected to become new targets for the treatment of certain neurological or psychiatric diseases. mGluRs belong to the C group of the GPCR superfamily. According to their different protein sequence homology, they can be divided into three categories: the first category includes mGluR1 and mGluR5; the second category includes mGluR2 and mGluR3; the third category includes mGluR4, mGluR6, mGluR7 and mGluR8. Among them, mGluR5 is highly expressed mainly in the central nervous system, and is enriched in the cerebral cortex, hippocampus, amygdala, thalamus, basal ganglia and other areas related to nervous system or mental system diseases. Studies have shown that patients with depression usually show hyperactivity of glutamatergic neurotransmitters, and after taking antidepressants, the release of glutamate in the patient's brain will decrease. mGluR5 is widely distributed, both on the presynaptic and postsynaptic membranes. Blocking the activity of mGluR5 receptors can not only reduce the release of glutamate by mediating the synthesis of γ-aminobutyric acid (GABA), but also weaken the activity of NMDA receptors and enhance the activity of AMPA receptors, achieving a synergistic antidepressant effect. Therefore, mGluR5 has become one of the hot targets for the treatment of depression.

[0004] In the design of mGluR5 target drugs, early studies mainly focused on designing small molecule competitive antagonists of endogenous ligands. However, due to the high conservation of mGluRs binding sites, it is difficult to obtain compounds with good selectivity for receptor subtypes. In addition, many endogenous ligands are often glutamate derivatives, lacking suitable pharmacokinetic properties and CNS permeability, making these compounds difficult to use in clinical research. In recent years, negative allosteric modulators of mGluR5 have attracted widespread attention. The compounds do not bind to the endogenous ligand site, but act on the allosteric site of the transmembrane region of GPCR. Therefore, they do not directly antagonize the receptor function, but indirectly enhance or weaken the activity induced by glutamate, thereby overcoming the defects of poor selectivity and permeability of competitive antagonists at the endogenous site of mGluRs. Therefore, the negative allosteric regulation site of mGluR5 is considered to be a very ideal drug target. On this basis, designing novel mGluR5 negative allosteric modulators for the treatment of central nervous system and mental system related diseases has very important significance and good application prospects.

[0005] In summary, there is an urgent need in the art to develop novel mGluR5 negative allosteric modulators. Summary of the invention

[0006] The purpose of the present invention is to provide a 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compound and its preparation method and use. The 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compound of the present invention has a simple preparation method and has targeting activity on the fifth subtype of metabotropic glutamate receptor (mGluR5), and has the potential efficacy of treating diseases related to the target.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In one aspect, the present invention provides a 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound, the general structural formula of which is shown in the following formula I:

[0009]

[0010] in, R is selected from substituted or unsubstituted phenyl, substituted or unsubstituted 5-6 membered heteroaryl; R is selected from substituted or unsubstituted phenyl, substituted or unsubstituted 6-membered heteroaryl.

[0011] The substituents are 1, 2, 3 or 4 substituents selected from the following: halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C3-C8 cycloalkyl, C3-C8 halocycloalkyl, cyano, nitro. The heteroaryl group independently contains 1 to 4 heteroatoms selected from nitrogen, oxygen or sulfur. The halogen is F, Cl, Br or I. The 5-6 membered heteroaryl group is any one of pyrazolyl, furanyl, oxazolyl, isoxazolyl, thiazolyl, imidazolyl, triazolyl, thienyl, thiadiazolyl, pyridyl, pyrimidinyl, pyrazinyl or pyridazinyl.

[0012] In the present invention, as a preferred technical solution, in Formula I, R is selected from substituted or unsubstituted phenyl, substituted or unsubstituted thiazolyl, substituted or unsubstituted pyridyl; R is selected from substituted or unsubstituted phenyl, substituted or unsubstituted pyridyl. Wherein the substituent is 1, 2, 3 or 4 substituents selected from the following: halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C3-C8 cycloalkyl, C3-C8 halocycloalkyl, cyano, nitro; the halogen is F, Cl, Br or I.

[0013] In the present invention, as another preferred technical solution, in Formula I, Selected from phenyl, 2-methylthiazol-4-yl, or pyridin-2-yl; R is selected from substituted or unsubstituted phenyl, pyridin-3-yl; wherein the substituent is 1, 2, 3 or 4 substituents selected from the following group: halogen, C1-C6 alkyl, C1-C6 alkoxy; the halogen is F, Cl, Br or I.

[0014] As a further preferred technical solution of the present invention, the 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compound is any one of the compounds shown in Table 1 below having a general formula I.

[0015] Table 1

[0016]

[0017]

[0018]

[0019]

[0020] Table 1 Represents phenyl, represents 4-fluorophenyl, Represents 4-chlorophenyl, represents 4-bromophenyl, represents 4-iodophenyl, represents 4-methylphenyl, represents 4-methoxyphenyl, represents 4-cyclopropylphenyl, represents 4-cyanophenyl, Represents 4-nitrophenyl, represents pyridin-2-yl, represents pyridin-3-yl, represents 2-methylthiazol-4-yl, represents 2-methyloxazol-4-yl, It represents 2-methyl-1H-imidazol-4-yl.

[0021] As a particularly preferred technical solution in the present invention, the 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound is selected from any one or a combination of at least two of the compounds in Table 2 below:

[0022] Table 2

[0023]

[0024]

[0025]

[0026] The alkyl group of the present invention refers to a straight chain or branched chain, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl and the like. A haloalkyl group refers to a group in which an alkyl group is substituted by one or more halogen atoms. An alkoxy group refers to a group in which an oxygen atom is attached to the end of an alkyl group, such as methoxy, ethoxy, n-propoxy, isopropoxy, tert-butoxy and the like. A haloalkoxy group refers to a group in which an alkoxy group is substituted by one or more halogen atoms. Halogen is F, Cl, Br or I.

[0027] The term "C1-C6 alkyl" used in the present invention refers to a straight or branched alkyl group having 1 to 6 carbon atoms, including, but not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, etc. The term "C1-C6 haloalkyl" refers to a straight or branched alkyl group having 1 to 6 carbon atoms substituted with a halogen atom, including, but not limited to, difluoromethyl, trifluoromethyl, etc. The term "C1-C6 alkoxy" refers to a straight or branched alkoxy group having 1 to 6 carbon atoms, including, but not limited to, methoxy, ethoxy, n-propoxy, isopropoxy and tert-butoxy, etc. The term "C1-C6 haloalkoxy" refers to a straight or branched alkoxy group having 1 to 6 carbon atoms substituted with a halogen atom, including, but not limited to, difluoromethoxy, trifluoromethoxy, etc. The term "C3-C8 cycloalkyl" refers to a cyclic alkyl group having 3 to 8 carbon atoms in the ring, including but not limited to cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, etc. The term "C3-C8 halocycloalkyl" refers to a cyclic alkyl group having 3 to 8 carbon atoms substituted with a halogen in the ring, including but not limited to 1-chlorocyclopropyl, 1-chlorocyclobutyl, etc.

[0028] In the present invention, C1-C6, C3-C8, etc. before the specific group represent the number of carbon atoms contained in the group. For example, C1-C6 represents a group with 1, 2, 3, 4, 5 or 6 carbon atoms, and C3-C8 represents a group with 3, 4, 5, 6, 7 or 8 carbon atoms.

[0029] On the other hand, the present invention also provides a method for preparing 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compounds. Unless otherwise noted, the groups in the reaction formula are defined as above.

[0030] The compound of general formula I of the present invention can be prepared by the following route:

[0031]

[0032] Wherein: Hal is selected from fluorine, chlorine, bromine or iodine; The definitions of the R substituents are the same as above and will not be repeated here.

[0033] The preparation process specifically includes the following steps:

[0034] Step 1: The compound of formula III is reacted with the compound of formula IV to obtain the compound of formula V.

[0035] The molar ratio of the compound of formula III to the compound of formula IV is 1:1.0-2.0, for example 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9 or 1:2.0.

[0036] In the present invention, the reaction in step 1 is carried out under the action of a catalyst and a base, and the catalyst is preferably any one of a copper catalyst, a palladium catalyst, a palladium-copper alloy catalyst, a nickel catalyst, and a platinum catalyst, or a combination of at least two thereof; the base is an organic base and / or an inorganic base. The organic base is preferably any one of triethylamine, N,N-diisopropylethylamine, N,N-dimethylaniline, pyridine, sodium methoxide, sodium ethoxide, sodium tert-butoxide, or potassium tert-butoxide, or a combination of at least two thereof; the inorganic base is preferably any one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, or sodium hydride, or a combination of at least two thereof.

[0037] The reaction solvent in step 1 is selected from any one of toluene, acetonitrile, tetrahydrofuran, 1,4-dioxane, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone or hexamethylphosphoric triamide, or a combination of at least two thereof.

[0038] The reaction temperature of step 1 is greater than or equal to 0°C and less than or equal to the boiling point of the reaction solvent, for example, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 60°C, 70°C, 75°C, 80°C, 85°C, 90°C, etc., or the reaction is carried out at the boiling point of the solvent, i.e., under reflux.

[0039] The reaction time of step 1 is 0.5-48 hours, for example 0.5 hours, 1 hour, 3 hours, 5 hours, 8 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, 23 hours, 25 hours, 28 hours, 30 hours, 33 hours, 35 hours, 38 hours, 40 hours, 44 hours or 48 hours.

[0040] Step 2: The compound of formula V is hydrolyzed to obtain the compound of formula II.

[0041] The hydrolysis in step 2 is carried out in any one of water, methanol, ethanol, tetrahydrofuran or 1,4-dioxane or a mixed solvent of at least two thereof.

[0042] Preferably, the hydrolysis in step 2 is carried out in the presence of an alkaline substance, and the alkaline substance is preferably sodium hydroxide, potassium hydroxide or lithium hydroxide.

[0043] Preferably, the amount of the alkaline substance is 1-5 times the molar amount of the compound of formula V. For example, 1 time, 1.3 times, 1.5 times, 2 times, 2.5 times, 3 times, 3.5 times, 4 times, 4.5 times or 5 times.

[0044] Step 3: The compound of formula II and the compound of formula VI are subjected to condensation reaction to obtain the compound of formula I.

[0045] The condensation reaction in step 3 is carried out in any one or a mixed solvent of at least two of dichloromethane, ethyl acetate, tetrahydrofuran, 1,4-dioxane, acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone or toluene.

[0046] Preferably, the condensation reaction in step 3 is carried out in the presence of an alkaline substance, and the alkaline substance is preferably any one of triethylamine, N,N-diisopropylethylamine, pyridine, sodium methoxide, sodium ethoxide, sodium tert-butoxide or potassium tert-butoxide, or a combination of at least two thereof.

[0047] Preferably, the condensation reaction in step 3 is carried out in the presence of a condensing agent, and the condensing agent is preferably any one of dicyclohexylcarbodiimide (DCC), O-(7-azabenzotriazole-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU), O-(benzotriazole-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HBTU), 6-chlorobenzotriazole-1,1,3,3-tetramethyluronium hexafluorophosphate (HCTU), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI), 1-hydroxybenzotriazole (HOBt) or diisopropylcarbodiimide (DIC), or a combination of at least two thereof.

[0048] Preferably, the molar ratio of the compound of formula II to the compound of formula VI is 1:1.0-2.0, for example 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9 or 1:2.0.

[0049] Preferably, the reaction temperature in step 3 is greater than or equal to 0°C and less than or equal to the boiling point of the reaction solvent, for example, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 60°C, 70°C, 75°C, 80°C, 85°C, 90°C, etc., or the reaction is carried out at the boiling point of the solvent, i.e., under reflux.

[0050] Preferably, the reaction time of step 3 is 0.5-48 hours, for example 0.5 hours, 1 hour, 3 hours, 5 hours, 8 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, 23 hours, 25 hours, 28 hours, 30 hours, 33 hours, 35 hours, 38 hours, 40 hours, 44 hours or 48 hours.

[0051] The preparation process of the 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compounds of the present invention involves an intermediate compound II, the structure of which is shown in Formula II:

[0052]

[0053] in, Selected from substituted or unsubstituted phenyl, substituted or unsubstituted thiazolyl, substituted or unsubstituted pyridyl, wherein the substituents are 1, 2, 3 or 4 substituents selected from the following group: halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C3-C8 cycloalkyl, C3-C8 halocycloalkyl, cyano, nitro; the halogen is F, Cl, Br or I.

[0054] The preparation method of the intermediate described in Formula II of the present invention has been mentioned above when describing the preparation method of Formula I, and will not be repeated here.

[0055] In the present invention, Table 3 shows representative compounds of the intermediate compounds of Formula II of the present invention, but the present invention is not limited thereto.

[0056] Table 3

[0057]

[0058] In another aspect, the present invention provides tautomers, enantiomers, diastereomers or pharmaceutically acceptable salts thereof of the 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compounds described above.

[0059] In the present invention, the tautomers, enantiomers, diastereomers or pharmaceutically acceptable salts of the 4-aromatic alkynyl substituted thieno [2,3-c] pyridine amide compounds can also exert the same effects as the 4-aromatic alkynyl substituted thieno [2,3-c] pyridine amide compounds.

[0060] On the other hand, the 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compounds, their tautomers, enantiomers, diastereomers or pharmaceutically acceptable salts thereof of the present invention can be used to treat diseases related to the metabotropic glutamate receptor subtype 5 (mGluR5) target, preferably for treating diseases selected from the group consisting of fragile X syndrome, Parkinson's levodopa-induced hyperactivity disorder (PD-LID), gastroesophageal reflux disease (GERD), autism, pain, anxiety, depression, drug addiction and the like.

[0061] Among them, the pharmaceutically acceptable salts are as follows:

[0062] The present invention provides pharmaceutically acceptable salts of the compounds of general formula I, specifically, conventional pharmaceutically acceptable salts formed by reacting the compounds of general formula I with inorganic acids or organic acids. For example, conventional pharmaceutically acceptable salts can be prepared by reacting a compound of formula I with an inorganic acid or an organic acid, wherein the inorganic acid includes hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, aminosulfonic acid and phosphoric acid, and the organic acid includes citric acid, tartaric acid, lactic acid, pyruvic acid, acetic acid, benzenesulfonic acid, p-toluenesulfonic acid, methanesulfonic acid, naphthalenesulfonic acid, ethanesulfonic acid, naphthalene disulfonic acid, maleic acid, malic acid, malonic acid, fumaric acid, succinic acid, propionic acid, oxalic acid, trifluoroacetic acid, stearic acid, pamoic acid, hydroxymaleic acid, phenylacetic acid, benzoic acid, salicylic acid, glutamic acid, ascorbic acid, p-aminobenzenesulfonic acid, 2-acetoxybenzoic acid and isethionic acid, or a sodium salt, potassium salt, calcium salt, aluminum salt or ammonium salt formed by a compound of formula I and an inorganic base; or a methylamine salt, ethylamine salt or ethanolamine salt formed by a compound of formula I and an organic base.

[0063] The present invention uses HDB Fluo-6 calcium fluorescence detection method to test the mGluR5 in vitro antagonist activity of the compound, and selects MPEP and known compound KC as positive control drugs. Through biological activity assay, it is found that some of the synthesized compounds have good mGluR5 in vitro negative allosteric regulation activity. Among them, the IC 50 The value was 10.2 nM, which was better than the positive controls MPEP and KC. DETAILED DESCRIPTION

[0064] The present invention is further described below in conjunction with specific examples. It should be understood by those skilled in the art that the examples are only used to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0065] Synthesis Example

[0066] Synthesis Example 1:

[0067] Preparation of 4-(phenylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (Compound No. 1):

[0068] (1) Preparation of ethyl 4-(phenylethynyl)thieno[2,3-c]pyridine-2-carboxylate, the specific preparation method is as follows:

[0069]

[0070] Dissolve 4-bromobenzo[2,3-c]pyridine-2-carboxylic acid ethyl ester (3.00 g, 10.48 mmol, 1.0 eq) in N,N-dimethylformamide (50 mL), add bistriphenylphosphine palladium dichloride (1.47 g, 2.10 mmol, 0.2 eq), cuprous iodide (399.34 mg, 2.10 mmol, 0.2 eq) and triethylamine (5.30 g, 52.42 mmol, 5.0 eq) in turn at room temperature, slowly dropwise add phenylacetylene (1.18 g, 11.53 mmol, 1.1 eq) under nitrogen protection, after adding the raw materials, heat the system to 100 ° C and react for 3 h, and terminate the reaction when the reaction no longer proceeds as monitored by TLC. The reaction solution was cooled to room temperature, water (50 mL) was added to the reaction solution, and extracted with ethyl acetate (30 mL*3). The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by column chromatography (eluent: petroleum ether: ethyl acetate = 10:1) to obtain a light yellow solid product, 4-(phenylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid ethyl ester (1.68 g, yield: 52.17%). 1 H NMR (400MHz, DMSO-d6) δ9.36 (s, 1H), 8.73 (s, 1H), 8.17 (d, J = 0.8Hz, 1H), 7.72 (dd, J=6.7,3.0Hz,2H),7.53-7.46(m,3H),4.41(q,J=7.1Hz,2H),1.37(t,J=7.1Hz,3H).

[0071] (2) Preparation of 4-(phenylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid, the specific preparation method is as follows:

[0072]

[0073] Dissolve 4-(phenylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid ethyl ester (1.68 g, 5.48 mmol, 1.0 eq) in 50 mL of methanol, add 10% aqueous sodium hydroxide solution (1.10 g, 27.39 mmol, 5.0 eq) at room temperature, react the system at 66°C for 3 h, adjust the system pH to 1-2 with 3 M hydrochloric acid, and a light yellow solid precipitates. Filter and dry the solid to obtain the product, namely 4-(phenylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid (1.38 g, yield: 90.19%). 1 H NMR (400MHz, DMSO-d6) δ9.47 (s, 1H), 8.81 (s, 1H), 8.22 (d, J = 0.8Hz, 1H), 7.78-7.70 (m, 2H), 7.53-7.47 (m, 3H).

[0074] (3) Preparation of 4-(phenylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide, the specific preparation method is as follows:

[0075]

[0076] 4-(Phenylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid (500.00 mg, 1.79 mmol, 1.0 eq) was dissolved in 30 mL of dichloromethane, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) (377.65 mg, 1.97 mmol, 1.1 eq) and 1-hydroxybenzotriazole (HOBt) (266.07 mg, 1.97 mmol, 1.1 eq) were added successively at room temperature. After reacting at room temperature for 30 min, aniline (183.38 mg, 1.97 mmol, 1 .1eq) and triethylamine (362.28mg, 3.58mmol, 2.0eq), and then the system was stirred at room temperature for 12h. After the reaction was completed, water (50mL) was added to the reaction solution, and it was extracted with dichloromethane (30mL*3). The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by column chromatography (eluent: petroleum ether: ethyl acetate = 4:1) to obtain a light yellow solid product 4-(phenylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (475.85mg, yield: 75.00%).

[0077] Compound 1 1 HNMR (400MHz, DMSO-d6) δ10.83(s,1H),9.37(s,1H),8.76(s,1H),8.61(d,J=0.8Hz,1H),7. 84-7.72(m,4H),7.55-7.51(m,3H),7.47-7.37(m,2H),7.23-7.13(m,1H).HRMS(ESI)calcd for C 22 H 14 N2OS[M+H + ]:355.0905,found:355.0985.

[0078] Synthesis Example 2:

[0079] Preparation of 4-(pyridin-2-ylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (Compound No. 12):

[0080] (1) Preparation of ethyl 4-(pyridin-2-ylethynyl)thieno[2,3-c]pyridine-2-carboxylate, the specific preparation method is as follows:

[0081]

[0082] Dissolve 4-bromobenzo[2,3-c]pyridine-2-carboxylic acid ethyl ester (4.00 g, 13.98 mmol, 1.0 eq) in N,N-dimethylformamide (50 mL), add bistriphenylphosphine palladium dichloride (1.97 g, 2.80 mmol, 0.2 eq), cuprous iodide (532.46 mg, 2.80 mmol, 0.2 eq) and triethylamine (7.07 g, 69.89 mmol, 5.0 eq) in turn at room temperature, slowly dropwise add 2-ethynylpyridine (1.59 g, 15.38 mmol, 1.1 eq) under nitrogen protection, after adding the raw materials, heat the system to 100 ° C and react for 4.5 h, and terminate the reaction when the reaction no longer proceeds as monitored by TLC. The reaction solution was cooled to room temperature, water (50 mL) was added to the reaction solution, and extracted with ethyl acetate (50 mL*3). The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by column chromatography (eluent: petroleum ether: ethyl acetate = 4:1) to obtain a light yellow solid product, 4-(pyridin-2-ylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid ethyl ester (3.83 g, yield: 88.86%). 1 H NMR (400MHz, DMSO-d6) δ9.44(s,1H),8.82(s,1H),8.69(d,J=4.5Hz,1H),8.20(d,J=0.6Hz,1H),7.94(td,J=7.7,1.8 Hz,1H),7.85(dt,J=7.8,1.1Hz,1H),7.50(ddd,J=7.6,4.8,1.3Hz,1H),4.43(q,J=7.1Hz,2H),1.38(t,J=7.1Hz,3H).

[0083] (2) Preparation of 4-(pyridin-2-ylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid, the specific preparation method is as follows:

[0084]

[0085] Dissolve 4-(pyridin-2-ylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid ethyl ester (3.83 g, 12.42 mmol, 1.0 eq) in 70 mL of methanol, add 10% aqueous sodium hydroxide solution (2.48 g, 62.10 mmol, 5.0 eq) at room temperature, react at 66°C for 3 h, adjust the pH of the system to 1-2 with 3 M hydrochloric acid, and a light grey solid precipitates. Filter and dry the solid to obtain the product, 4-(pyridin-2-ylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid (3.20 g, yield: 91.95%). 1H NMR (400MHz, DMSO-d6) δ9.53(s,1H),8.88(s,1H),8.70(s,1H),8.21(s,1H),8.00(t,J=7.7Hz,1H),7.91(d,J=7.9Hz,1H),7.57-7.54(m,1H).

[0086] (3) Preparation of 4-(pyridin-2-ylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide, the specific preparation method is as follows:

[0087]

[0088] 4-(Pyridin-2-ylethynyl)thieno[2,3-c]pyridine-2-carboxylic acid (500.00 mg, 1.78 mmol, 1.0 eq) was dissolved in 30 mL of dichloromethane, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) (375.73 mg, 1.96 mmol, 1.1 eq) and 1-hydroxybenzotriazole (HOBt) (265.14 mg, 1.96 mmol, 1.1 eq) were added successively at room temperature. After reacting at room temperature for 30 min, aniline (182.73 mg, 1.96 mmol, 1. 1eq) and triethylamine (361.00mg, 3.57mmol, 2.0eq), and then the system was stirred at room temperature for 12h. After the reaction was completed, water (50mL) was added to the reaction solution, and it was extracted with dichloromethane (50mL*3). The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by column chromatography (eluent: petroleum ether: ethyl acetate = 2:1) to obtain a light yellow solid product 4-(pyridin-2-ylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (412.09mg, yield: 65.00%).

[0089] Compound 12 1 HNMR(400MHz,DMSO-d6)δ10.90(s,1H),9.41(s,1H),8.82(s,1H),8.74-8.68(m,1H),8.63(s,1H),7.96(td,J=7.7,1.8Hz,1H),7.90- 7.83(m,1H),7.79(d,J=7.6Hz,2H),7.52(ddd,J=7.6,4.9,1.2Hz,1H),7.42(t,J=7.9Hz,2H),7.18(t,J=7.4Hz,1H).HRMS(ESI)calcd for C 21 H 13 N3OS[M+H +]:356.0858,found:356.1140.

[0090] Synthesis Example 3:

[0091] Preparation of 4-((2-methylthiazol-4-yl)ethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (Compound No. 23):

[0092] (1) Preparation of ethyl 4-((2-methylthiazol-4-yl)ethynyl)thieno[2,3-c]pyridine-2-carboxylate, the specific preparation method is as follows:

[0093]

[0094] Dissolve 4-bromobenzo[2,3-c]pyridine-2-carboxylic acid ethyl ester (5.00 g, 17.47 mmol, 1.0 eq) in N,N-dimethylformamide (60 mL), add bistriphenylphosphine palladium dichloride (2.45 g, 3.49 mmol, 0.2 eq), cuprous iodide (665.57 mg, 3.49 mmol, 0.2 eq) and triethylamine (8.84 g, 87.37 mmol, 5.0 eq) in turn at room temperature, slowly dropwise add 4-ethynyl-2-methylthiazole (2.37 g, 19.22 mmol, 1.1 eq) under nitrogen protection, after adding the raw materials, heat the system to 100 ° C and react for 5 h, and terminate the reaction when the reaction no longer proceeds as monitored by TLC. The reaction solution was cooled to room temperature, water (60 mL) was added to the reaction solution, and extracted with ethyl acetate (50 mL*3). The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by column chromatography (eluent was petroleum ether: ethyl acetate = 4:1) to obtain a light yellow solid product, 4-((2-methylthiazol-4-yl)ethynyl)thieno[2,3-c]pyridine-2-carboxylic acid ethyl ester (3.74 g, yield: 65.17%). 1 H NMR (400MHz, DMSO-d6) δ9.42(s,1H),8.76(s,1H),8.17(s,1H),7.38(s,1H),4.43(q,J=5.8,4.6Hz,2H),2.72(s,3H),1.37(t,J=7.1Hz,3H).

[0095] (2) Preparation of 4-((2-methylthiazol-4-yl)ethynyl)thieno[2,3-c]pyridine-2-carboxylic acid, the specific preparation method is as follows:

[0096]

[0097] Dissolve 4-((2-methylthiazol-4-yl)ethynyl)thieno[2,3-c]pyridine-2-carboxylic acid ethyl ester (3.74 g, 11.39 mmol, 1.0 eq) in 50 mL of methanol, add 10% aqueous sodium hydroxide solution (2.28 g, 56.94 mmol, 5.0 eq) at room temperature, react at 66°C for 3 h, adjust the pH of the system to 1-2 with 3 M hydrochloric acid, and a light yellow solid precipitates. Filter and dry the solid to obtain the product, 4-((2-methylthiazol-4-yl)ethynyl)thieno[2,3-c]pyridine-2-carboxylic acid (3.17 g, yield: 92.69%). 1 H NMR (400MHz, DMSO-d6) δ9.41(s,1H),8.76(s,1H),8.17(s,1H),7.40(br s,1H),2.72(s,3H).

[0098] (3) Preparation of 4-((2-methylthiazol-4-yl)ethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide, the specific preparation method is as follows:

[0099]

[0100] 4-((2-methylthiazol-4-yl)ethynyl)thieno[2,3-c]pyridine-2-carboxylic acid (1.00 g, 3.33 mmol, 1.0 eq) was dissolved in 50 mL of dichloromethane, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) (701.62 mg, 3.66 mmol, 1.1 eq) and 1-hydroxybenzotriazole (HOBt) (494.87 mg, 3.66 mmol, 1.1 eq) were added successively at room temperature. After reacting at room temperature for 30 min, aniline (341.06 mg, 3.66 mmol, 1. 1eq) and triethylamine (673.80mg, 6.66mmol, 2.0eq), and then the system was stirred at room temperature for 12h. After the reaction was completed, water (50mL) was added to the reaction solution, and extracted with dichloromethane (50mL*3). The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by column chromatography (eluent: petroleum ether: ethyl acetate = 2:1) to obtain a light yellow solid product 4-((2-methylthiazol-4-yl)ethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (1.00g, yield: 80.10%).

[0101] Compound 23 1HNMR(400MHz,DMSO-d6)δ10.90(s,1H),9.39(s,1H),8.76(s,1H),8.59(d,J=0.8Hz,1H),8.12(s,1H ),7.81-7.76(m,2H),7.41(dd,J=8.5,7.4Hz,2H),7.20-7.15(m,1H),2.73(s,3H).HRMS(ESI)calcd for C 20 H 13 N3OS2[M+H + ]:376.0578,found:376.0781.

[0102] In addition to the compounds described above, the compounds in Table 1 can be prepared or can be prepared by similar methods to those in Synthesis Examples 1-3. Table 4 below gives the NMR and mass spectrometry data of some compounds synthesized with reference to Synthesis Examples 1-3.

[0103] Table 4

[0104]

[0105] Other compounds of general formula I of the present invention can be synthesized by referring to the above method.

[0106] Pharmacological Activity Test Example

[0107] Example 1: The physicochemical parameters of the compounds are shown in Table 5

[0108] Table 5 Physical and chemical properties of the compounds

[0109] serial number LogP CLogP tPSA 1 4.48 5.55144 41.46 3 5.04 6.32184 41.46 6 4.97 6.05044 41.46 11 3.14 4.53378 53.82 12 3.57 4.05444 53.82 14 4.12 4.82484 53.82 17 4.05 4.55344 53.82 23 4.31 4.39444 53.82 25 4.87 5.16484 53.82 28 4.80 4.89344 53.82 MPEP 3.77 3.782 12.36

[0110] Note: The physicochemical properties of the compounds (LogP, CLogP and tPSA values) are the predicted values ​​by Chemdraw software in the ChemOffice software package.

[0111] The results showed that the physicochemical properties (LogP, CLogP and tPSA values) of this type of compound were close to those of positive drugs (MPEP) and had good drugability.

[0112] Example 2. mGluR5 in vitro activity test

[0113] Experimental materials: HEK293 / mGluR5 cell line, Fluo-6 calcium ion fluorescent dye, positive controls MPEP and KC.

[0114] Experimental instrument: FLIPR Tetra real-time fluorescence imaging analysis system.

[0115] Experimental method: HDB Fluo-6 calcium fluorescence detection method.

[0116] Experimental principle: HDB Fluo-6 calcium ion fluorescence detection method is a fast, simple and reliable fluorescence detection method for detecting changes in intracellular calcium ion concentration. Fluo 6-AM fluorescent dye is an acetyl methyl ester derivative of Fluo 6. Through cultivation, it can easily penetrate the cell membrane and enter the cell. After entering the cell, the fluorescent dye will be hydrolyzed by intracellular esterase. The produced Fluo 6 is a polar molecule that is not easy to penetrate the lipid bilayer membrane and will be retained in the cell. Then it will react with calcium ions (Ca 2+ ) bind and emit fluorescence.

[0117] Cells expressing the target GPCR receptor protein (mGluR5) are first calibrated with a calcium ion-sensitive fluorescent probe and then stimulated with a compound. After stimulation, receptor activation triggers calcium ion mobilization, and the fluorescent probe captures calcium ions to trigger a fluorescent signal, which can be read out using a fluorescent plate reader. If the screened compound can activate mGluR5, the calcium flow response can be greatly increased; conversely, if the screened compound can antagonize mGluR5, the calcium flow response can be greatly reduced. The experimental results are shown in Table 6 below.

[0118] Table 6. Inhibitory effects of compounds on mGluR5

[0119]

[0120]

[0121] Experimental conclusion: According to the above-mentioned mGluR5 in vitro activity test method, compound 14 of the present invention and known compounds MPEP and KC were selected for parallel testing of mGluR5 in vitro activity. From the data obtained in the above table, it can be seen that the activity of some newly synthesized compounds is better than that of known compounds MPEP and KC, and has the potential to treat mGluR5 target-related diseases.

[0122] The present invention uses the above teaching content to illustrate the 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compounds of the present invention and their preparation methods and uses, but the present invention is not limited to the above content. Those skilled in the art should understand that various changes or modifications are made to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compound, characterized in that Its general structural formula is shown in the following formula I: in, R is selected from substituted or unsubstituted phenyl, substituted or unsubstituted 5-6 membered heteroaryl; R is selected from substituted or unsubstituted phenyl, substituted or unsubstituted 6-membered heteroaryl; wherein the substituents are 1, 2, 3 or 4 substituents selected from the following substituents: halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C3-C8 cycloalkyl, C3-C8 halocycloalkyl, cyano, nitro; the halogen is F, Cl, Br or I.

2. The 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound according to claim 1, characterized in that: Selected from phenyl, 2-methylthiazol-4-yl or pyridin-2-yl; R is selected from substituted or unsubstituted phenyl, pyridin-3-yl; wherein the substituent is 1, 2, 3 or 4 substituents selected from the following group: halogen, C1-C6 alkyl, C1-C6 alkoxy; the halogen is F, Cl, Br or I.

3. The 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound according to claim 1, characterized in that The 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound is selected from any one of the following compounds: 4-(Phenylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (Compound No. 1); 4-(Phenylacetyl)-N-(4-chlorophenyl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 3); 4-(Phenylethynyl)-N-(p-tolyl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 6); 4-(Phenylethynyl)-N-(pyridin-3-yl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 11); 4-(Pyridin-2-ylethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (Compound No. 12); 4-(Pyridin-2-ylethynyl)-N-(4-chlorophenyl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 14); 4-(Pyridin-2-ylethynyl)-N-(p-tolyl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 17); 4-((2-methylthiazol-4-yl)ethynyl)-N-phenylthieno[2,3-c]pyridine-2-carboxamide (Compound No. 23); 4-((2-methylthiazol-4-yl)ethynyl)-N-(4-chlorophenyl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 25); 4-((2-methylthiazol-4-yl)ethynyl)-N-(p-tolyl)thieno[2,3-c]pyridine-2-carboxamide (Compound No. 28).

4. The method for preparing the 4-aromatic alkynyl substituted thieno[2,3-c]pyridine amide compound according to claim 1, characterized in that The synthetic route is as follows: Wherein: Hal is selected from fluorine, chlorine, bromine or iodine.

5. The preparation method according to claim 4, characterized in that The steps include: Step 1: Under the action of a catalyst and a base, the compound of formula III reacts with the compound of formula IV to obtain the compound of formula V; Step 2: In the presence of an alkaline substance, the compound of formula V is hydrolyzed to obtain a compound of formula II; Step 3: In the presence of a basic substance and a condensation agent, the compound of formula II and the compound of formula VI are subjected to a condensation reaction to obtain a compound of formula I.

6. Use of the 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound of claim 1, or its tautomer, enantiomer, diastereomer or pharmaceutically acceptable salt thereof in the preparation of a negative allosteric modulator of mGluR5.

7. Use of the 4-aromatic alkynyl-substituted thieno[2,3-c]pyridine amide compound of claim 1, or its tautomer, enantiomer, diastereomer or pharmaceutically acceptable salt thereof in the preparation of a drug for treating diseases related to the fifth subtype of metabotropic glutamate receptor mGluR5.

8. The use according to claim 7, characterized in that: The diseases associated with the fifth subtype of metabotropic glutamate receptor mGluR5 include one or more of fragile X syndrome, Parkinson's disease, levodopa-induced hyperactivity, gastroesophageal reflux disease, autism, pain, anxiety, depression and drug addiction.

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