Indazole compound or pharmaceutically acceptable salt thereof and preparation method and application thereof

Abstract

The present invention belongs to the field of pharmaceutical chemistry technology, and specifically relates to an indazole compound represented by formula (I) or a pharmaceutically acceptable salt thereof, and a preparation method and application thereof. The compound represented by formula (I) exhibits PDE4 inhibitory activity and can be used to prepare drugs for treating inflammatory diseases, autoimmune diseases or neuropsychiatric diseases, especially for preparing drugs for treating inflammatory allergic diseases, autoimmune diseases, central nervous system diseases or organ diseases related to ischemic reflow caused by heart failure, shock and cerebrovascular diseases, and similar diseases.

Description

Technical Field

[0001] The present invention belongs to the technical field of pharmaceutical chemistry, and specifically relates to indazole compounds or pharmaceutically acceptable salts thereof and applications. Background Art

[0002] Cyclic nucleotide phosphodiesterases (PDEs) can specifically use cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) as substrates, and control their intracellular concentrations by catalyzing the hydrolysis of cAMP and / or cGMP to generate the corresponding AMP and / or GMP, thereby affecting a variety of physiological processes and metabolic functions. The PDEs family contains a total of 11 subtypes (PDEs1-PDEs11), which can be divided into three categories based on their fifth: cAMP-specific hydrolases (PDE4, PDE7 and PDE8), cGMP-specific hydrolases (PDE5, PDE6 and PDE9) and dual hydrolases (PDE1, PDE2, PDE3, PDE10 and PDE11). Among them, PDE4 and PDE9 can regulate many physiological and pathological activities, such as cell apoptosis, energy metabolism, learning and memory, inflammatory immune response, vision, olfaction and the growth of various cell types by regulating cAMP and cGMP, respectively, and further activating protein kinase A (PKA) and protein kinase G (PKG) pathways.

[0003] PDE4 has four subtypes, PDE4A-D. Except for PDE4C, the other three subtypes are highly expressed in the cerebral cortex, olfactory bulb, hippocampus and brainstem. In addition, PDE4B is also highly expressed in the striatum, amygdala, hypothalamus and thalamus. A large number of studies have confirmed that PDE4 is widely involved in various activities of brain nerves. PDE4 inhibitors inhibit PDE4 to upregulate cAMP concentration, activate the cAMP / PKA / CREB pathway to regulate BDNF concentration, promote the growth of nerve cell synapses, increase synaptic plasticity and neuronal survival, and achieve the purpose of improving cognitive function; in addition, the upregulation of cAMP concentration can inhibit the nuclear transfer of NF-B, and then downregulate the level of intracellular inflammatory factors (such as TNF-α, IL-1 and IL-6, etc.), relieve neuroinflammation, and reduce inflammation-induced neuronal damage and apoptosis. PDE4 inhibitors have been used in the study of many diseases, such as asthma, chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, atopic dermatitis, psoriasis, Alzheimer's disease, schizophrenia, depression, etc.

[0004] At present, there are only three PDE4 inhibitors on the market: roflumilast, apremilast and crisaborole, and in actual clinical applications, the above three PDE4 inhibitors all have adverse reactions to varying degrees. It can be seen that there are very few types of PDE4 inhibitors available for selection, and it is still necessary to continue researching and developing new PDE4 inhibitors. Summary of the invention

[0005] The object of the present invention is to provide a novel compound or a pharmacologically acceptable salt thereof having PDE4 inhibitory effect, and a pharmaceutical composition containing the same. The novel indazole compound discovered by the present invention has not been reported in patents or literature, and exhibits good PDE4 inhibitory activity.

[0006] Another object of the present invention is to provide a method for preparing the indazole compound.

[0007] Another object of the present invention is to provide the application of the azole compound.

[0008] To achieve the above object, the present invention is implemented by the following technical solutions:

[0009] An indazole compound or a pharmaceutically acceptable salt thereof, wherein the indazole compound or a pharmaceutically acceptable salt thereof has the structure of formula (I):

[0010]

[0011] Where R 1 is selected from methoxy, difluoromethoxy, ethoxy or methylamino;

[0012] R 2 Selected from C 3-6 Cycloalkyl or C substituted by one or more first substituents 3-6 Cycloalkyl, the first substituent is selected from hydroxyl, halogen atom, C 1-6 Alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy, carboxyl, C 1-6 an alkoxycarbonyl group, an amino group, an amide group or a carbamoyl group;

[0013] R 3 is selected from C substituted by one or more second substituents 5-9 Cyclic group, C 5-9 Heterocyclic group, or C 5-9 heteroaryl, the second substituent is selected from hydroxyl, halogen, carboxyl, C 1-6 Alkoxy, ester, amide, C 1-6 Alkoxy, C 5-9 Heterocyclic group, or C 5-9Heteroaryl.

[0014] Furthermore, the R 1 is methoxy, ethoxy, difluoromethyl or methylamino; R 2 Cyclopropyl, R 3 for

[0015] Furthermore, the R 1 is methoxy; R 2 is cyclopropyl; R 3 for The R 1 is methoxy; R 2 for R 3 for

[0016] The R 1 is difluoromethyl; R 2 is cyclopropyl; R 3 for

[0017] Furthermore, the R 1 is methoxy; R 2 is cyclopropyl or R 3 for

[0018] The R 1 is difluoromethyl; R 2 is cyclopropyl; R 3 for

[0019] The R 1 is ethoxy or methylamino; R 2 is cyclopropyl; R 3 for

[0020] Furthermore, the R 1 is methoxy; R 2 is cyclopropyl; R 3 for

[0021] The R 1 is difluoromethyl; R 2 is cyclopropyl; R 3 for

[0022] Furthermore, the R1 is methoxy; R 2 When it is cyclopropyl, R 3 for

[0023] R 1 is difluoromethyl; R 2 When it is cyclopropyl, R 3 for

[0024] More specifically and preferably, the indazole compounds or pharmaceutically acceptable salts thereof that can be prepared by the present invention are partially listed as follows:

[0025]

[0026]

[0027] The "pharmaceutically acceptable salt" used in the present invention refers to the salt of the compound of the present invention, more specifically, refers to the acid salt, that is, prepared from the compound with specific substituents found in the present invention and a relatively non-toxic acid.

[0028] Pharmaceutically acceptable acid addition salts include inorganic acid salts, such as hydrochloric acid, hydrobromic acid, nitric acid, carbonic acid, phosphoric acid, sulfuric acid, phosphite, and the like; and organic acid salts, such as acetic acid, propionic acid, isobutyric acid, maleic acid, malonic acid, benzoic acid, succinic acid, suberic acid, fumaric acid, lactic acid, mandelic acid, phthalic acid, benzenesulfonic acid, p-toluenesulfonic acid, citric acid, tartaric acid, and the like.

[0029] The preparation method of the indazole compound comprises the following steps:

[0030] S1. Prepare the compound of formula (II);

[0031] S2. The compound of formula (II) and R 3 -X undergoes coupling reaction to obtain a compound represented by formula (I);

[0032] X is B(OH)2, B(Pin)2 or H;

[0033]

[0034] The pharmaceutically acceptable salt of the indazole compound can be prepared by a salt-forming reaction after the compound represented by formula (I) is prepared.

[0035] More specifically, the preparation method of the indazole compound can be Compound is used as raw material and prepared according to the following reaction:

[0036]

[0037] Another object of the present invention is to provide the use of the indazole compound or a pharmaceutically acceptable salt thereof in the preparation of a drug for treating phosphodiesterase 4-related diseases.

[0038] Furthermore, the phosphodiesterase 4-related disease refers to allergic diseases, autoimmune diseases, central nervous system diseases, or ischemic regurgitation diseases caused by heart failure, shock and cerebrovascular disease.

[0039] In view of the fact that PDE4 inhibitors have been well studied and used in a variety of diseases, such as asthma, chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, atopic dermatitis, psoriasis, Alzheimer's disease, schizophrenia, depression, etc. Therefore, the compounds with PDE4 inhibitory activity involved in the present invention can also be used to prepare drugs for treating inflammatory allergic diseases, autoimmune diseases, central nervous system diseases or organ diseases related to ischemic reflow caused by heart failure, shock and cerebrovascular disease, and similar diseases.

[0040] The inflammatory allergic disease is, for example, asthma, chronic obstructive pulmonary disease (COPD), allergic rhinitis or nephritis.

[0041] The autoimmune disease is, for example, rheumatoid arthritis, multiple sclerosis, Crohn's disease or systemic lupus erythematosus.

[0042] The central nervous system disease is, for example, depression, amnesia or dementia.

[0043] The compounds of the present invention can also be used to prepare drugs that are beneficial for preventing, treating or improving Parkinson's disease, Parkinson's syndrome and other diseases, stroke and vascular dementia-related diseases.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention provides an indazole compound or a pharmaceutically acceptable salt thereof, wherein the indazole compound or a pharmaceutically acceptable salt thereof exhibits good inhibitory activity against PDE4. Among them, the in vitro enzyme inhibitory activity of compounds 10, 14 and 15 against PDE4 is comparable to that of the marketed drug Apremilast. In addition, in a Parkinson's cell model, the test compound shows no obvious toxicity to human neuroblastoma cells (SH-SY5Y) within the range of efficacy, and has a protective effect on rotenone-induced SH-SY5Y cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a fitted dose-effect curve of the inhibition rate of the enzyme at different concentrations of the compounds prepared in Examples 10, 14, 15 and 17; Figure 2Cytotoxicity test diagram of the compounds prepared in Example 10 and Example 17;

[0047] Figure 3 Schematic diagram reflecting the protective effects of the compounds prepared in Example 10 and Example 17 on rotenone-induced SH-SY5Y cell damage.

[0048] Figure 4 This is a schematic diagram reflecting the protective effect of the compound prepared in Example 10 on HT-22 cell injury in the oxygen glucose deprivation / reoxygenation model (OGD / R). DETAILED DESCRIPTION

[0049] The present invention is further described in detail below in conjunction with specific examples, which are only used to explain the present invention and are not used to limit the scope of the present invention. The test methods used in the following examples are conventional methods unless otherwise specified; the materials and reagents used are reagents and materials that can be obtained from commercial channels unless otherwise specified.

[0050] The synthetic routes of Examples 1 to 13:

[0051]

[0052] Example 1

[0053]

[0054] Preparation of 3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)benzonitrile (Compound 1)

[0055] Synthesis route:

[0056]

[0057] Step 1: Synthesis of intermediate 1-1

[0058] 2-Fluoro-4-bromoanisole (200mmol, 1.0equiv.) was dissolved in tetrahydrofuran (500mL), and a tetrahydrofuran solution of lithium diisopropylamide (2.0M, 120mL, 1.2equiv.) was added dropwise at -80°C under argon protection. After stirring for 30 minutes, the temperature was raised to -20°C, and ethyl formate (300mmol, 1.5equiv.) was slowly added dropwise. After the temperature was raised to 0°C and stirring was continued for 1 hour, a saturated ammonium chloride solution was added dropwise to quench. After the mixed liquid was diluted with ethyl acetate, the organic phase was washed with saturated ammonium chloride solution and saturated brine, dried over anhydrous sodium sulfate, decolorized with activated carbon, filtered with diatomaceous earth, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was recrystallized from ethyl acetate / anhydrous ethanol / petroleum ether (100mL, volume ratio 2:1:10) to obtain a white or light yellow solid (yield 82%).

[0059] 1 H NMR (400MHz, CDCl3, ppm) δ10.32 (s, 1H), 7.38 (d, J = 8.8Hz, 1H), 7.04 (t, J = 8.4Hz, 1H), 3.91 (s, 3H). 13 C NMR (100MHz, CDCl3, ppm) δ 188.63 (d, J = 3.1Hz), 154.58, 151.93, 147.97 (d, J = 9.8Hz), 129.15 (d, J = 4.7Hz), 118.67 (d, J = 3.7Hz), 114.00, 56.76.

[0060] Step 2: Synthesis of intermediate 1-3

[0061] Compound 1-1 (100 mmol, 1.0 equiv.) was dissolved in dimethyl sulfoxide (100 mL), and sodium azide (150 mmol, 1.5 equiv.) was slowly added in batches under room temperature protection. After stirring for 5 minutes, the temperature was raised to 60°C, stirred for 8 hours, and then cooled to room temperature. The mixed liquid was diluted with water and a saturated potassium carbonate solution (20 mL) was added, and extracted with ethyl acetate. The aqueous phase was quenched with a diluted potassium permanganate solution, and the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by rapid silica gel chromatography with ethyl acetate / petroleum ether = 1:5 (V / V) as the eluent to obtain a yellow solid (yield 95%).

[0062] 1 H NMR (400MHz, CDCl3, ppm) δ10.32 (s, 1H), 7.35 (d, J = 8.8Hz, 1H), 6.90 (d, J = 8.8Hz, 1H), 3.93 (s, 3H). 13 C NMR (100MHz, CDCl3, ppm) δ189.92,153.56,130.14,126.59,116.21,114.41,106.45,56.49.

[0063] Step 3: Synthesis of intermediate 1-3:

[0064] Compound 1-2 (50 mmol, 1.0 equiv.) was dissolved in dimethyl sulfoxide (50 mL), and cyclopropylamine (50 mmol, 1.0 equiv.) was added under room temperature protection. After stirring for 5 minutes, the temperature was raised to 80°C, stirred for 2 hours, and then cooled to room temperature. The mixed liquid was diluted with water and then added with dilute hydrochloric acid solution (3.0 M, 10 mL), extracted with ethyl acetate, and the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by rapid silica gel chromatography with ethyl acetate / petroleum ether = 1:3 (V / V) as the eluent to obtain a white solid (yield 90%).

[0065] 1 H NMR (400MHz, CDCl3, ppm) δ7.93 (s, 1H), 7.07 (d, J = 8.0Hz, 1H), 6.40 (d, J = 8.0Hz, 1H), 4.00–3.89 (m, 4H), 1.40–1.28 (m, 2H), 1.17–1.08 (m, 2H). 13 C NMR (100MHz, CDCl3, ppm) δ149.59,141.53,124.33,124.30,124.02,103.56,102.79,55.55,34.75,7.26.

[0066] Step 4: Synthesis of compound 1

[0067] Compound 1-3 (0.5mmol, 1.0equiv.), 3-cyanophenylboronic acid (0.6mmol, 1.2equiv.), tetrakistriphenylphosphine palladium (0.05mmol, 0.1equiv.), potassium carbonate (1mmol, 2equiv.) were dissolved in NN-dimethylformamide (50mL), stirred at 80°C under argon protection for 4 hours, cooled to room temperature, diluted with water, extracted with ethyl acetate, the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:3 (V / V) as the eluent to obtain a white solid (yield 80%), namely 3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)benzonitrile (Compound 1).

[0068] 1H NMR (400MHz, CDCl3, ppm) δ8.07(s,1H),7.89(s,1H),7.83(d,J=7.6Hz,1H),7.61(d,J=7.6Hz,1H),7.55(t,J=7.6Hz,1H) ,7.06(d,J=7.6Hz,1H),6.63(d,J=7.6Hz,1H),4.04(s,3H),3.98–3.92(m,1H),1.43–1.34(m,2H),1.17(q,J=7.2Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ150.42,141.94,141.65,131.94,131.02,130.20,129. 58,123.79,122.62,122.26,121.59,118.93,112.82,102.80,55.55,34.76,7.29.

[0069] Example 2

[0070]

[0071] Preparation of 1-(3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)phenyl)ethan-1-one (Compound 2)

[0072] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by 3-acetylphenylboronic acid to prepare 1-(3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)phenyl)ethan-1-one (compound 2).

[0073] 1 H NMR (400MHz, CDCl3, ppm) δ8.19(s,1H),8.08(s,1H),7.90(d,J=7.6Hz,1H),7.79(d,J=7.6Hz,1H),7.53(t,J=7.6Hz,1H),7.08( d,J=7.6Hz,1H),6.62(d,J=7.6Hz,1H),4.03(s,3H),3.98–3.90(m,1H),2.64(s,3H),1.40–1.31(m,2H),1.13(q,J=6.4Hz,2H). 13C NMR (100MHz, CDCl3, ppm) δ198.14,149.90,141.93,140.83,137.51,132.20,128.93, 127.27,126.76,125.19,122.89,121.88,121.74,102.78,55.44,34.65,26.73,7.21.

[0074] Example 3

[0075]

[0076] Preparation of 2-cyclopropyl-7-methoxy-4-(3,4,5-trimethoxyphenyl)-2H-indazole (Compound 3)

[0077] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by 3,4,5-trimethoxyphenylboronic acid to prepare 2-cyclopropyl-7-methoxy-4-(3,4,5-trimethoxyphenyl)-2H-indazole (Compound 3).

[0078] 1 H NMR (400MHz, CDCl3, ppm) δ8.07 (s, 1H), 7.02 (d, J = 7.6Hz, 1H), 6.81 (s, 2H), 6.60 (d, J = 7. 6Hz,1H),4.03(s,3H),3.98–3.90(m,10H),1.37(q,J=4.4,4.0Hz,2H),1.18–1.10(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ153.39,149.54,141.96,137.19,136.28,126.47, 123.05,122.20,121.05,105.00,102.71,60.94,56.23,55.46,34.66,7.24.

[0079] Example 4

[0080]

[0081] Preparation of 3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)benzamide (Compound 4)

[0082] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by (3-carbamoylphenyl)boronic acid to prepare 3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)benzamide (Compound 4).

[0083] 1 H NMR (400MHz, CDCl3, ppm) δ8.07(d,J=5.2Hz,2H),7.74(d,J=7.6Hz,2H),7.50(t,J=7.6Hz,1H),7.05(d,J=7.6Hz,1H), 6.58(d,J=7.6Hz,1H),6.29(d,J=126.0Hz,2H),4.00(s,3H),3.92–3.85(m,1H),1.37–1.30(m,2H),1.15–1.04(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ169.53,149.86,141.91,140.88,133.88,131.09,128. 97,126.74,125.55,125.20,123.02,121.87,121.76,102.82,55.45,34.65,7.24.

[0084] Example 5

[0085]

[0086] Preparation of 2-cyclopropyl-7-methoxy-4-(3-phenoxyazetidin-1-yl)-2H-indazole (Compound 5)

[0087] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by 3-phenoxyazetidine to prepare 2-cyclopropyl-7-methoxy-4-(3-phenoxyazetidine-1-yl)-2H-indazole (Compound 5).

[0088] 1 H NMR (400MHz, CDCl3, ppm) δ7.85 (s, 1H), 7.29 (q, J = 11.6, 9.2Hz, 2H), 7.00 (d, J = 6.8Hz, 1H), 6.82 (d, J = 7.2Hz, 2H), 6.43 (d, J = 7.2Hz, 1H), 5.83 (d,J=7.2Hz,1H),5.15–5.03(m,1H),4.43(d,J=7.2Hz,2H),4.02(t,J=6.4Hz,2H),3.90(d,J=22.8Hz,4H),1.33(s,2H),1.10(d,J=6.0Hz,2H). 13C NMR (100MHz, CDCl3, ppm) δ156.75,143.28,142.72,137.92,129.62,121.83, 121.33,114.97,114.56,103.02,100.09,66.55,60.05,55.39,34.35,7.08.

[0089] Example 6

[0090]

[0091] Preparation of (3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)phenyl)formamide (Compound 6)

[0092] The preparation process is the same as that of Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced with (3-(aminomethyl)phenyl)borate hydrochloride to prepare (3-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)phenyl)formamide (Compound 6).

[0093] 1 H NMR (400MHz, CDCl3, ppm) δ8.09(s,1H),7.55(s,1H),7.50(d,J=7.6Hz,1H),7.41(t,J=7.6Hz,1H),7.29(d,J=7.6Hz,1H) ,7.05(d,J=7.6Hz,1H),6.61(d,J=7.6Hz,1H),4.02(s,3H),3.98–3.88(m,3H),1.38–1.32(m,2H),1.12(q,J=7.2Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ149.52,143.53,141.98,140.69,128.89,126.47,126. 27,126.25,125.65,123.18,122.08,121.33,102.84,55.41,46.45,34.58,7.19.

[0094] Example 7

[0095]

[0096] Preparation of 1-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)-1H-indole-5-carbonitrile (Compound 7)

[0097] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by 5-cyanoindole to prepare 1-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)-1H-indole-5-carbonitrile (Compound 7).

[0098] 1 H NMR (400MHz, CDCl3, ppm) δ8.05(s,1H),7.70(s,1H),7.47(d,J=3.2Hz,1H),7.40(d,J=8.4Hz,1H),7.33(d,J=8.4Hz,1H),7.06(d,J= 7.6Hz,1H),6.77(d,J=3.2Hz,1H),6.62(d,J=7.6Hz,1H),4.08(s,3H),3.94–3.86(m,1H),1.37–1.31(m,2H),1.13(q,J=7.2Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ150.00,142.27,138.03,130.93,128.41,126.59,124.96,122. 87,121.87,120.61,120.19,119.16,111.62,103.64,103.21,102.11,55.80,34.93,7.39.

[0099] Example 8

[0100]

[0101] Preparation of 3-benzyl-5-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)benzonitrile (Compound 8)

[0102] The preparation process is the same as that in Example 1, except that the 3-cyanophenylboronic acid in step 4 is replaced by (3-benzyl-5-cyanophenyl)boronic acid to prepare 3-benzyl-5-(2-cyclopropyl-7-methoxy-2H-indazol-4-yl)benzonitrile (Compound 8).

[0103] 1H NMR (400MHz, CDCl3, ppm) δ7.85(s,1H),7.73(s,1H),7.62(s,1H),7.44(s,1H),7.36(t,J=7.2Hz,2H),7.28(d,J=7.2Hz,1H),7.23(d,J=7.6H z,2H),7.04(d,J=7.6Hz,1H),6.61(d,J=7.6Hz,1H),4.08(s,2H),4.04(s,3H),3.95–3.85(m,1H),1.36–1.31(m,2H),1.16(q,J=7.2Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ150.36,143.20,141.90,141.68,139.50,132.55,130.36,128.98,128.84, 128.78,126.69,123.78,122.53,122.07,121.55,118.98,112.82,102.77,55.52,41.41,34.68,7.25.

[0104] Example 9

[0105]

[0106] Preparation of 2-cyclopropyl-4-(3,4-dimethoxyphenyl)-7-methoxy-2H-indazole (Compound 9)

[0107] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by (3,4-dimethoxyphenyl)boric acid to prepare 2-cyclopropyl-4-(3,4-dimethoxyphenyl)-7-methoxy-2H-indazole (Compound 9).

[0108] 1 H NMR (400MHz, CDCl3, ppm) δ8.07 (s, 1H), 7.20–7.11 (m, 2H), 6.99 (dd, J = 16.7, 7.8Hz, 2H), 6. 61(d,J=7.6Hz,1H),4.03(s,3H),3.96–3.90(m,7H),1.42–1.30(m,2H),1.21–1.09(m,2H). 13C NMR (100MHz, CDCl3, ppm) δ149.13,148.26,142.04,133.43,126.35,123.13, 122.31,120.77,119.97,111.48,111.26,102.91,56.00,55.45,34.61,7.22.

[0109] Example 10

[0110]

[0111] Preparation of 2-cyclopropyl-7-methoxy-4-(pyridin-4-yl)-2H-indazole (Compound 10)

[0112] The preparation process is the same as that in Example 1, except that 3-cyanophenylboronic acid in step 4 is replaced by 4-pyridineboronic acid to prepare 2-cyclopropyl-7-methoxy-4-(pyridin-4-yl)-2H-indazole (Compound 10).

[0113] 1 H NMR (400MHz, CDCl3, ppm) δ8.65(d,J=4.2Hz,2H),8.14(s,1H),7.56–7.47(m,2H),7.17(d,J=7.6Hz ,1H),6.63(d,J=7.6Hz,1H),4.04(s,3H),3.99–3.88(m,1H),1.42–1.34(m,2H),1.20–1.11(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ150.95,150.13,147.77,142.00,123.21,122.71,122.60,122.21,121.33,102.81,55.57,34.76,7.28.

[0114] Embodiment 11

[0115]

[0116] Preparation of 1-(4-(3-cyanophenyl)-7-methoxy-2H-indazol-2-yl)-N-isobutylcyclopropane-1-carboxamide (Compound 11)

[0117] The preparation process is the same as that of Example 1, except that the cyclopropylamine in step 3 is replaced by 1-amino-N-isobutylcyclopropane-1-carboxamide to prepare 1-(4-(3-cyanophenyl)-7-methoxy-2H-indazol-2-yl)-N-isobutylcyclopropane-1-carboxamide (Compound 11).

[0118] 1 H NMR (400MHz, CDCl3, ppm) δ8.17(s,1H),7.88–7.79(m,2H),7.64(d,J=7.6Hz,1H),7.58(t,J=7.6z,1H),7.13(d,J=7.6Hz,1H),6.71(d, J=7.6Hz,1H),5.89(t,J=6.0Hz,1H),4.08(s,3H),3.00(t,J=6.4Hz,2H),1.96–1.92(m,2H),1.68–1.56(m,3H),0.77(d,J=6.8Hz,6H). 13 C NMR (100MHz, CDCl3, ppm) δ169.07,150.44,143.38,141.12,131.90,131.04,130.57,129.74,125 .13,124.17,123.29,121.81,118.74,113.11,103.79,55.72,47.21,46.58,28.31,19.91,16.38.

[0119] Example 12

[0120]

[0121] Preparation of 1-(4-(3-acetylphenyl)-7-methoxy-2H-indazol-2-yl)-N-isobutylcyclopropane-1-carboxamide (Compound 12)

[0122] The preparation process is the same as that in Example 1, except that the cyclopropylamine in step 3 is replaced by 1-amino-N-isobutylcyclopropane-1-carboxamide, and the 3-cyanophenylboronic acid in step 4 is replaced by 3-acetylphenylboronic acid to prepare 1-(4-(3-acetylphenyl)-7-methoxy-2H-indazol-2-yl)-N-isobutylcyclopropane-1-carboxamide (Compound 12).

[0123] 1H NMR (400MHz, CDCl3, ppm) δ8.18(s,2H),7.94(d,J=7.6Hz,1H),7.79(dd,J=7.6,1.8Hz,1H),7.57(t,J=7.6Hz,1H),7.16(d,J=7.6Hz,1H),6.70(d,J= 7.6Hz,1H),5.94(t,J=6.0Hz,1H),4.07(s,3H),3.00(t,J=6.4Hz,2H),2.6 6(s,3H),1.93(q,J=4.8Hz,2H),1.68–1.59(m,3H),0.77(d,J=6.8Hz,6H). 13 C NMR (100MHz, CDCl3, ppm) δ198.02,169.27,149.97,143.43,140.36,137.72,132.17,129.14,127.26 ,127.21,125.62,125.41,122.82,122.16,103.83,55.65,47.21,46.50,28.30,26.75,19.90,16.39.

[0124] Embodiment 13

[0125]

[0126] Preparation of 1-(4-(3-acetylphenyl)-7-methoxy-2H-indazol-2-yl)-N-cyclopentylcyclopropane-1-carboxamide (Compound 13)

[0127] The preparation process is the same as that in Example 1, except that the cyclopropylamine in step 3 is replaced by 1-amino-N-cyclopentylcyclopropane-1-carboxamide, and the 3-cyanophenylboronic acid in step 4 is replaced by 3-acetylphenylboronic acid to prepare 1-(4-(3-acetylphenyl)-7-methoxy-2H-indazol-2-yl)-N-cyclopentylcyclopropane-1-carboxamide (Compound 13).

[0128] 1H NMR (400MHz, CDCl3, ppm) δ8.17(d,J=6.4Hz,2H),7.93(d,J=7.6Hz,1H),7.79(d,J=8.0Hz,1H),7.57(t,J=7.6Hz,1H),7.16(d,J=7.6Hz,1H),6.70( d,J=7.6Hz,1H),5.82(d,J=7.3Hz,1H),4.07(s,4H),2.66(s,3H),1.95–1 .85(m,4H),1.57(q,J=4.8Hz,2H),1.54–1.44(m,4H),1.29–1.16(m,3H). 13 C NMR (100MHz, CDCl3, ppm) δ197.99,168.72,150.00,143.33,140.36,137.71,132.17,129.12,127.24 ,127.18,125.59,125.34,122.73,122.08,103.73,55.63,51.80,46.47,32.72,26.75,23.57,16.45.

[0129] Embodiment 14

[0130]

[0131] Preparation of 2-cyclopropyl-7-(difluoromethoxy)-4-(3,4,5-trimethoxyphenyl)-2H-indazole (Compound 14)

[0132] Synthesis route:

[0133]

[0134] Step 1: Synthesis of Intermediate 14-1

[0135] 2-Cyclopropyl-4-bromo-7-methoxy-indazole (Intermediate 1-3 in Example 1, 100 mmol, 1.0 equiv.) was dissolved in anhydrous dichloromethane (200 mL), and anhydrous aluminum chloride (120 mmol, 1.2 equiv.) was slowly added in batches at 0°C under argon protection. After stirring for 30 minutes, the mixture was heated to room temperature and stirred for 1 hour. After adding acetic acid (10 mL), the mixture was filtered under reduced pressure using short diatomaceous earth and rinsed with dichloromethane. The solvent was evaporated under reduced pressure to obtain a crude product. The crude product was recrystallized from ethyl acetate / anhydrous ethanol / petroleum ether (30 mL, volume ratio 2:1:2) to obtain a white solid (yield 90%).

[0136] 1H NMR (400MHz, CDCl3, ppm) δ9.16 (s, 1H), 7.93 (s, 1H), 7.10 (d, J = 7.8Hz, 1H), 6. 65(d,J=7.8Hz,1H),4.00–3.92(m,1H),1.27–1.21(m,2H),1.19–1.13(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ145.88,141.62,125.52,124.63,124.15,109.77,101.64,34.45,7.33.

[0137] Step 2: Synthesis of Intermediate 14-2

[0138] Compound 14-1 (90 mmol, 1.0 equiv.) and diethyl bromofluoromethylphosphonate (135 mmol, 1.5 equiv.) were dissolved in acetonitrile (100 mL), and a saturated aqueous solution of potassium hydroxide (90 mmol, 1.0 equiv.) was added dropwise at 0°C under argon protection. After stirring for 1 hour, the organic phase was diluted with ethyl acetate, washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography using ethyl acetate / petroleum ether = 1:10 (V / V) as the eluent to obtain a yellow liquid (yield 95%).

[0139] 1 H NMR (400MHz, CDCl3, ppm) δ8.04 (s, 1H), 7.14 (t, 2 J FH =73.8Hz,1H),7.12(s,1H),6.87(d,J=7.6Hz,1H),4.02–3.90(m,1H),1.41–1.35(m,2H),1.23–1.17(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ140.97, 140.26, 125.35, 124.76, 123.88, 115.64 (t, J = 259.5Hz), 114.68, 108.50, 35.06, 7.48.

[0140] Step 3: Synthesis of compound 14

[0141] Compound 14-2 (0.5mmol, 1.0equiv.), 3,4,5-trimethoxyphenylboronic acid (0.6mmol, 1.2equiv.), tetrakistriphenylphosphine palladium (0.05mmol, 0.1equiv.), potassium carbonate (1mmol, 2equiv.) were dissolved in NN-dimethylformamide (50mL), stirred at 80°C under argon protection for 4 hours, cooled to room temperature, diluted with water, extracted with ethyl acetate, the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:3 (V / V) as the eluent to obtain a white solid (yield 80%), namely 2-cyclopropyl-7-(difluoromethoxy)-4-(3,4,5-trimethoxyphenyl)-2H-indazole (compound 14).

[0142] 1 H NMR (400MHz, CDCl3, ppm) δ8.13 (s, 1H), 7.19 (t, 2 J FH =73.8Hz,1H),7.08–6.97(m,2H),6.80(s,2H),4.01–3.87(m,10H),1.36(q,J=4.8Hz,2H),1.19(q,J=6.6Hz,2H). 13 CNMR (100 MHz, CDCl3, ppm) δ 153.52, 141.51, 140.11, 137.85, 135.50, 131.68, 123.74, 123.23, 120.36, 115.84 (t, J = 259 Hz), 114.04, 105.33, 60.95, 56.31, 34.93, 7.46. Example 15

[0143]

[0144] Preparation of 1-(3-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)phenyl)ethan-1-one (Compound 15)

[0145] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by 3-acetylphenylboronic acid to prepare 1-(3-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)phenyl)ethan-1-one (Compound 15).

[0146] 1H NMR (400 MHz, CDCl3, ppm) δ8.19 (s, 1H), 8.13 (s, 1H), 7.95 (d, J = 7.6 Hz, 1H), 7.79 (d, J = 7.6 Hz, 1H), 7.57 (t, J = 7.7 Hz, 1H), 7.21 (t, 2 J FH =73.8 Hz,1H),7.10–7.00(m,2H),4.02–3.90(m,1H),2.65(s,3H),1.42–1.32(m,2H),1.27–1.13(m,1H). 13 C NMR (100MHz, CDCl3, ppm) δ197.95,141.45,140.57,140.15,137.66,132.39 ,130.39,129.13,127.53,127.48,123.59,122.96,120.97,115.80(t,J=259 Hz),113.87,34.95,26.71,7.44.

[0147] Example 16

[0148]

[0149] Preparation of 2-(1-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)azetidin-3-yl)propanol (Compound 16)

[0150] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by 2-(azetidin-3-yl)propanol to prepare 2-(1-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)azetidin-3-yl)propanol (Compound 16).

[0151] 1 H NMR (400 MHz, CDCl3, ppm) δ7.93 (s, 1H), 6.89 (t, 2 J FH =73.8 Hz,1H),6.88(d,J=6.6 Hz,1H),5.69(d,J=7.6 Hz,1H),4.07(t,J=7.6 Hz,2H),3.96(t,J=6.4 Hz,2H),3.91–3.83(m,1H),2.79(p,J=7.6 Hz,1H),1.33–1.27(m,2H),1.24(s,6H),1.16–1.11(m,2H). 13C NMR (100 MHz, CDCl3, ppm) δ142.95,142.67,131.93,122.75,116.62,116.28 (t, J=258 Hz),114.83,98.08,69.80,53.83,40.50,34.47,26.85,7.21.

[0152] Embodiment 17

[0153]

[0154] Preparation of 2-cyclopropyl-7-(difluoromethoxy)-4-(pyridin-4-yl)-2H-indazole (Compound 17)

[0155] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by 4-pyridinephenylboronic acid to prepare 2-cyclopropyl-7-(difluoromethoxy)-4-(pyridin-4-yl)-2H-indazole (Compound 17).

[0156] 1 H NMR (400MHz, CDCl3, ppm) δ8.71(d,J=4.0Hz,2H),8.18(s,1H),7.53(d,J=4.8Hz,2H),7.23(t, 2 J FH =73.8Hz,1H),7.15(d,J=7.6Hz,1H),7.12–7.00(m,1H),4.10–3.87(m,1H),1.44–1.33(m,2H),1.24–1.16(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ150.26, 147.21, 141.50, 141.42, 128.25, 123.31, 122.52, 122.37, 121.62, 115.67 (t, J = 259.5Hz), 113.61, 35.04, 7.50.

[0157] Embodiment 18

[0158]

[0159] Preparation of 4-(2-chloropyridin-4-yl)-2-cyclopropyl-7-(difluoromethoxy)-2H-indazole (Compound 18)

[0160] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-chloropyridin-4-yl)boric acid to prepare 4-(2-chloropyridin-4-yl)-2-cyclopropyl-7-(difluoromethoxy)-2H-indazole (Compound 18).

[0161] 1 H NMR (400MHz, CDCl3, ppm) δ8.44–8.37(m,1H),8.17(s,1H),7.49(d,J=4.0Hz,1H),7.43–7.37(m,1H),7.23(t, 2 J FH =73.8Hz,1H),7.12–7.05(m,1H),7.01(d,J=7.6Hz,1H),4.02–3.91(m,1H),1.43–1.34(m,2H),1.23–1.16(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ152.08,150.09,149.97,141.88,141.15,126.69,123 .14,122.57,122.03,121.97,121.17,115.58(t,J=259Hz),113.24,35.07,7.49.

[0162] Embodiment 19

[0163]

[0164] Preparation of 2-cyclopropyl-7-(difluoromethoxy)-4-(2-fluoropyridin-4-yl)-2H-indazole (Compound 18)

[0165] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-fluoropyridin-4-yl)boric acid to prepare 2-cyclopropyl-7-(difluoromethoxy)-4-(2-fluoropyridin-4-yl)-2H-indazole (Compound 18).

[0166] 1 H NMR (400MHz, CDCl3, ppm) δ8.28(d,J=5.2Hz,1H),8.19(s,1H),7.40(d,J=5.2Hz,1H),7.25(t, 2 J FH=72Hz,1H),7.18–7.12(m,2H),7.05(d,J=7.2Hz,1H),4.03–3.95(m,1H),1.42–1.37(m,2H),1.24–1.18(m,2H). 13 C NMR (100MHz, CDCl3, ppm) δ164.35 (d, J = 238.2Hz), 152.63 (d, J = 8.2Hz), 148.10 (d, J = 15.7Hz), 141.95, 141.30, 127.05 (d, J =3.4Hz), 123.18, 122.17, 121.98, 120.31 (d, J = 3.7Hz), 115.63 (t, J = 259.5Hz), 113.37, 107.85 (d, J = 38.0Hz), 35.11, 7.52.

[0167] Embodiment 20

[0168]

[0169] Preparation of 2-cyclopropyl-7-(difluoromethoxy)-4-(2-methoxypyridin-4-yl)-2H-indazole (Compound 20)

[0170] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-methoxypyridin-4-yl)boric acid to prepare 2-cyclopropyl-7-(difluoromethoxy)-4-(2-methoxypyridin-4-yl)-2H-indazole (Compound 20).

[0171] 1 H NMR (400MHz, CDCl3, ppm) δ8.22 (d, J = 5.2Hz, 1H), 8.17 (s, 1H), 7.22 (t, 2 J FH =73.8Hz,1H),7.10(t,J=7.2Hz,2H),7.03(d,J=6.8Hz,1H),6.94(s,1H),4.01–3.92(m,4H),1.39–1.32(m,2H),1.17(q,J=6.8Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ164.75,149.74,147.31,141.36,128.45,123.47,122. 40,121.29,116.13,115.72(t,J=259.5Hz),113.54,109.26,53.49,34.97,7.44.

[0172] Embodiment 21

[0173]

[0174] Preparation of 2-cyclopropyl-7-(difluoromethoxy)-4-(2-methylaminopyridin-4-yl)-2H-indazole (Compound 21)

[0175] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-methylaminopyridin-4-yl)boric acid to prepare 2-cyclopropyl-7-(difluoromethoxy)-4-(2-methylaminopyridin-4-yl)-2H-indazole (Compound 21).

[0176] 1 H NMR (400MHz, CDCl3, ppm) δ8.20–8.14(m,2H),7.22(t, 2 J FH =73.8Hz,1H),7.11(d,J=7.6Hz,1H),7.07–7.02(m,1H),6.82(d,J=5.2Hz,1H),6.56(s,1H ),4.73(br,1H),4.02–3.91(m,1H),2.98(s,3H),1.40–1.35(m,2H),1.19(q,J=6.8Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ160.07,148.67,148.55,141.41,141.04,129.64,123.58 ,122.61,120.86,115.73(t,J=259Hz),113.69,112.36,104.66,34.94,29.16,7.44.

[0177] Embodiment 22

[0178]

[0179] Preparation of 4-(4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)pyridin-2-yl)morpholine (Compound 22)

[0180] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-morpholinopyridin-4-yl)boric acid to prepare 4-(4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)pyridin-2-yl)morpholine (Compound 22).

[0181] 1H NMR (400MHz, CDCl3, ppm) δ8.28 (d, J = 5.2Hz, 1H), 8.14 (s, 1H), 7.22 (t, 2 J FH =73.8Hz,1H),7.10(d,J=7.6Hz,1H),7.04(d,J=8.0Hz,1H),6.90(d,J=5.2Hz,1H),6.80(s,1H),4 .00–3.93(m,1H),3.90–3.81(m,4H),3.61–3.51(m,4H),1.41–1.35(m,2H),1.19(q,J=6.8Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ160.22,148.85,148.39,141.40,141.09,129.74,123.52,122 .68,120.99,115.74(t,J=259.5Hz),113.70,113.39,105.65,66.73,45.69,35.01,7.50.

[0182] Embodiment 23

[0183]

[0184] Preparation of 4-(3-chloropyridin-4-yl)-2-cyclopropyl-7-(difluoromethoxy)-2H-indazole (Compound 23)

[0185] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-chloropyridin-4-yl)boric acid to prepare 4-(3-chloropyridin-4-yl)-2-cyclopropyl-7-(difluoromethoxy)-2H-indazole (Compound 23).

[0186] 1 H NMR (400MHz, CDCl3, ppm) δ8.73 (s, 1H), 8.56 (d, J = 4.8Hz, 1H), 7.85 (s, 1H), 7.35 (d, J = 4.8Hz, 1H), 7.26 (t, 2 J FH =73.8Hz,1H),7.09–7.03(m,2H),4.02–3.90(m,1H),1.38–1.34(m,2H),1.18(q,J=7.0Hz,2H). 13C NMR (100MHz, CDCl3, ppm) δ150.34,147.83,145.67,141.52,140.96,130.47,125. 61,125.43,123.74,122.97,122.78,115.74(t,J=259.5Hz),113.10,35.07,7.55.

[0187] Embodiment 24

[0188]

[0189] Preparation of 4-(3-fluoropyridin-4-yl)-2-cyclopropyl-7-(difluoromethoxy)-2H-indazole (Compound 24)

[0190] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by (2-fluoropyridin-4-yl)boric acid to prepare 4-(3-fluoropyridin-4-yl)-2-cyclopropyl-7-(difluoromethoxy)-2H-indazole (Compound 24).

[0191] 1 H NMR (400MHz, CDCl3, ppm) δ8.59 (s, 1H), 8.51 (d, J = 4.8Hz, 1H), 8.00 (s, 1H), 7.49–7.43 (m, 1H), 7.26 (t, 2 J FH =73.8Hz,1H),7.16(d,J=7.6Hz,1H),7.08(d,J=7.6Hz,1H),4.01–3.93(m,1H),1.42–1.36(m,2H),1.20(q,J=7.2Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ156.30 (d, J = 257.8Hz), 146.05 (d, J = 5.1Hz), 141.88, 141.08, 139.07 (d, J = 25.1Hz), 134.3 6(d,J=12.3Hz),124.56,123.87(d,J=5.2Hz),123.42(d,J=2.2Hz),122.74,122.25,115.71(t,J=259.5Hz),113.34.

[0192] Embodiment 25

[0193]

[0194] Preparation of 4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)morpholine (Compound 25)

[0195] The preparation process is the same as that of Example 14, except that 3,4,5-trimethoxyphenylboronic acid in step 3 is replaced by morpholine to prepare 4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)morpholine (Compound 25).

[0196] 1 H NMR (400MHz, CDCl3, ppm) δ7.98 (s, 1H), 7.01 (t, 2 J FH =73.8Hz,1H),6.90(d,J=8.0Hz,1H),6.29(d,J=8.0Hz,1H),3.96–3.88(m,5H),3.19–3.13(m,4H),1.41–1.31(m,2H),1.17(q,J=6.8Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ142.80, 142.69, 135.86, 122.61, 118.59, 116.01 (t, J = 258Hz), 115.00, 105.67, 67.01, 51.76, 34.65, 7.30.

[0197] Embodiment 26

[0198]

[0199] Preparation of N-benzyl-4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)picolinamide (Compound 26)

[0200] Synthesis route:

[0201]

[0202] Step 1: Synthesis of Intermediate 26-1

[0203] 4-Bromopyridine-2-carboxylic acid (10 mmol, 1.0 equiv.) was dissolved in dichloromethane and N,N-dimethylformamide (20 mL, volume ratio 1:1), and 1-propylphosphoric acid cyclic anhydride ethyl acetate solution (12 mmol, 50 wt%, 1.2 equiv.) was added dropwise at room temperature. After stirring for 10 minutes, benzylamine (15 mmol, 1.5 equiv.) and diisopropylethylamine (15 mmol, 1.5 equiv.) were added. After stirring for 15 minutes, the mixture was diluted with dichloromethane, and the organic phase was washed with dilute hydrochloric acid solution, saturated potassium carbonate solution and saturated brine in sequence, dried over anhydrous sodium sulfate, decolorized with activated carbon, filtered with diatomaceous earth, and the solvent was evaporated under reduced pressure to obtain the product (yield 99%).

[0204] 1 H NMR (400MHz, CDCl3, ppm) δ8.40 (s, 1H), 8.38–8.19 (m, 2H), 7.59 (d, J = 5.2Hz, 1H), 7.35 (d, J = 4.4Hz, 4H), 7.31–7.27 (m, 1H), 4.66 (d, J = 6.0Hz, 2H). 13 C NMR (100MHz, CDCl3, ppm) δ162.94,150.91,148.77,137.86,134.42,129.36,128.70,127.79,127.54,125.99,43.56.

[0205] Step 2: Synthesis of Intermediate 26-2

[0206] Compound 26-1 (8 mmol, 1.0 equiv.), biboronic acid pinacol ester (9.6 mmol, 1.2 equiv.), [1,1'-bis(diphenylphosphino)ferrocene] dichloropalladium (0.04 mmol, 0.05 equiv.) and potassium acetate (24 mmol, 3 equiv.) were dissolved in N,N-dimethylformamide (10 mL), heated to 80°C under argon protection, stirred for 4 hours, cooled to room temperature, the mixed liquid was diluted with water, extracted with ethyl acetate, the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by rapid silica gel chromatography with ethyl acetate / petroleum ether = 2:1 (V / V) as the eluent to obtain a yellow oil (yield 90%).

[0207] 1H NMR (400MHz, CDCl3, ppm) δ8.58 (s, 1H), 8.52 (d, J = 4.4Hz, 1H), 8.35 (t, J = 6.0Hz, 1H), 7.74 ( d,J=4.4Hz,1H),7.39–7.31(m,4H),7.31–7.27(m,1H),4.67(d,J=6.0Hz,2H),1.34(s,12H). 13 C NMR (100MHz, CDCl3, ppm) δ164.39,149.00,147.42,138.27,131.25,128.61,127.80,127.47,127.36,84.67,43.43,24.96.

[0208] Step 3: Synthesis of compound 26

[0209] Compound 14-2 (0.5 mmol, 1.0 equiv.), compound 26-2 (0.6 mmol, 1.2 equiv.), tetrakistriphenylphosphine palladium (0.05 mmol, 0.1 equiv.), potassium carbonate (1 mmol, 2 equiv.) in Example 14 were dissolved in NN-dimethylformamide (50 mL), stirred at 80°C under argon protection for 4 hours, cooled to room temperature, diluted with water, extracted with ethyl acetate, the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:3 (V / V) as the eluent to obtain a white solid (yield 80%), namely N-benzyl-4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)picolinamide (Compound 26).

[0210] 1 H NMR (400MHz, CDCl3, ppm) δ8.60 (d, J = 5.2Hz, 1H), 8.52 (s, 1H), 8.46 (t, J = 6.4Hz, 1H), 8.27(s,1H),7.64(d,J=5.2Hz,1H),7.42–7.34(m,4H),7.30(t,J=6.8Hz,1H),7.26(t, 2 J FH =73.8Hz,1H),7.23(d,J=7.6Hz,1H),7.10–7.06(m,1H),4.71(d,J=6.0Hz,2H),4.04–3.94(m,1H),1.44–1.37(m,2H),1.20(q,J=6.9Hz,2H). 13C NMR (100MHz, CDCl3, ppm) δ164.19,150.45,148.75,148.64,141.92,141.38,138.11,128.73,127.84,127 .60,127.52,124.67,123.52,122.24,122.03,120.96,115.70(t,J=259Hz),113.47,43.57,35.12,7.58.

[0211] Embodiment 27

[0212]

[0213] Preparation of 4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)-N-isobutylpyridineamide (Compound 27)

[0214] The preparation process is the same as that of Example 26, except that in step 1, benzylamine is replaced by isobutylamine to prepare intermediate 27-1, in step 2, intermediate 26-1 is replaced by intermediate 27-1 to prepare intermediate 27-2, and in step 3, intermediate 26-2 is replaced by intermediate 27-2 to prepare 4-(2-cyclopropyl-7-(difluoromethoxy)-2H-indazol-4-yl)-N-isobutylpicolinamide (Compound 27).

[0215] Intermediate 27-1: 1 H NMR (400MHz, CDCl3, ppm) δ8.38–8.29(m,2H),8.03(s,1H),7.57(d,J=5.2Hz,1H),3.28(t,J=6.4Hz,2H),1.95–1.84(m,1H),0.96(d,J=6.8Hz,6H). 13 C NMR (100MHz, CDCl3, ppm) δ162.96,151.15,148.69,134.39,129.18,125.83,46.82,28.62,20.10.

[0216] Intermediate 27-2: 1 H NMR (400MHz, CDCl3, ppm) δ8.54–8.51(m,2H),8.11(t,J=6.0Hz,1H),7.72(d,J=4.8Hz ,1H),3.29(t,J=6.6Hz,2H),1.94–1.84(m,1H),1.33(s,12H),0.96(d,J=6.7Hz,6H). 13C NMR (100MHz, CDCl3, ppm) δ164.39,149.21,147.31,131.04,127.30,84.61,46.67,28.65,24.77,20.12.

[0217] Compound 27: 1 H NMR (400MHz, CDCl3, ppm) δ8.62(d,J=4.8Hz,1H),8.48(s,1H),8.27(s,1H),8.22(t,J=6.4Hz,1H),7.64(d,J=4.8Hz,1H),7.25(t, 2 J FH =73.8Hz,1H),7.24–7.21(m,1H),7.10–7.05(m,1H),4.02–3.94(m,1H),3.35(t,J=6.4H z,2H),2.01–1.90(m,1H),1.43–1.37(m,2H),1.23–1.16(m,2H),1.02(d,J=6.8Hz,6H). 13 C NMR (100MHz, CDCl3, ppm) δ164.23,150.70,148.68,148.59,141.88,141.39,127.68,124.50,123 .55,122.26,121.99,120.83,115.70(t,J=259.5Hz),113.48,46.86,35.11,28.74,20.21,7.57.

[0218] Embodiment 28

[0219]

[0220] Preparation of 2-cyclopropyl-7-ethoxy-4-(pyridin-4-yl)-2H-indazole (Compound 28)

[0221] Synthesis route:

[0222]

[0223] Step 1: Synthesis of intermediate 28-1

[0224] Compound 14-1 (2mmol, 1.0equiv.), iodoethane (3mmol, 1.5equiv.) and potassium carbonate (3mmol, 1.5equiv.) were dissolved in DMF (5mL). After stirring at room temperature for 24 hours, the mixture was diluted with water and extracted with ethyl acetate. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:10 (V / V) as the eluent to obtain a colorless liquid (yield 85%).

[0225] 1 H NMR (400MHz, CDCl3, ppm) δ7.90 (s, 1H), 7.05 (d, J=8.0Hz, 1H), 6.39 (d, J=8.0Hz, 1H), 4.20 (q, J= 7.2Hz,2H),3.99–3.89(m,1H),1.53(t,J=7.2Hz,3H),1.35–1.28(m,2H),1.15(q,J=7.0Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ148.85,141.78,124.41,124.38,123.73,104.37,102.53,63.96,34.71,14.56,7.29.

[0226] Step 2: Synthesis of compound 28

[0227] Compound 28-1 (0.5mmol, 1.0equiv.), 4-pyridineboronic acid (0.6mmol, 1.2equiv.), tetrakistriphenylphosphine palladium (0.05mmol, 0.1equiv.), potassium carbonate (1mmol, 2equiv.) were dissolved in NN-dimethylformamide (50mL), stirred at 80°C under argon protection for 4 hours, cooled to room temperature, diluted with water, extracted with ethyl acetate, the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:3 (V / V) as the eluent to obtain a white solid (yield 80%), namely 2-cyclopropyl-7-ethoxy-4-(pyridin-4-yl)-2H-indazole (compound 28).

[0228] 1H NMR (400MHz, CDCl3, ppm) δ8.63(s,2H),8.11(s,1H),7.52(d,J=4.4Hz,2H),7.20–7.10(m,1H),6.62(d,J=6.7H z,1H),4.30(q,J=6.8Hz,2H),4.03–3.90(m,1H),1.62–1.53(m,3H),1.38–1.30(m,2H),1.16(d,J=6.8Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ150.28,149.89,148.02,142.18,122.81,122.78,122.43,122.24,121.33,103.55,63.97,34.72,14.60,7.31.

[0229] Embodiment 29

[0230]

[0231] Preparation of 2-cyclopropyl-7-methylamino-4-(pyridin-4-yl)-2H-indazole (Compound 29)

[0232] Synthesis route:

[0233]

[0234] Step 1: Synthesis of Intermediate 29-1

[0235] Compound 14-1 (2mmol, 1.0equiv.), 2-bromopropionamide (2mmol, 1.0equiv.) and sodium hydroxide (2mmol, 1.0equiv.) were dissolved in DMF (5mL). After stirring at room temperature for 24 hours, sodium hydroxide (2mmol, 1.0equiv.) was added and the temperature was raised to 90°C and stirred for 2 hours. The mixture was diluted with water and extracted with ethyl acetate. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:1 (V / V) as the eluent to obtain a yellow solid (yield 80%).

[0236] 1 H NMR (400MHz, CDCl3, ppm) δ7.89 (s, 1H), 6.99 (d, J = 7.6Hz, 1H), 6.33 (d, J = 7.6Hz, 1H), 3.94–3.88 (m, 1H), 1.35–1.30 (m, 2H), 1.17 (q, J = 7.2Hz, 2H). 13C NMR (100MHz, CDCl3, ppm) δ141.42,135.67,125.16,123.92,123.48,106.58,99.49,34.48,7.17.

[0237] Step 2: Synthesis of intermediate 4-bromo-2-cyclopropyl-7-methylamino-2H-indazole (29-2): Compound 29-1 (1 mmol, 1.0 equiv.) and paraformaldehyde (1.5 mmol, 1.5 equiv.) were dissolved in methanol (3 mL). Sodium methoxide (2 mmol, 2 equiv.) was slowly added at room temperature. After stirring for 24 hours, sodium borohydride (5 mmol, 5 equiv.) was slowly added to the mixture. After stirring for 10 hours, the mixture was diluted with water and extracted with ethyl acetate. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography using ethyl acetate / petroleum ether = 1:5 (V / V) as the eluent to obtain a white solid (yield 70%).

[0238] 1 H NMR (400MHz, CDCl3, ppm) δ7.86 (s, 1H), 7.06 (d, J = 7.7Hz, 1H), 6.06 (d, J = 7.8Hz ,1H),3.92–3.82(m,1H),2.95(s,3H),1.32–1.27(m,2H),1.14(q,J=7.2Hz,2H). 13 CNMR (100MHz, CDCl3, ppm) δ141.27,138.73,125.55,123.82,122.84,100.63,97.52,34.28,29.98,7.05.

[0239] Step 3: Synthesis of compound 29

[0240] Compound 29-1 (0.5mmol, 1.0equiv.), 4-pyridineboronic acid (0.6mmol, 1.2equiv.), tetrakistriphenylphosphine palladium (0.05mmol, 0.1equiv.), potassium carbonate (1mmol, 2equiv.) were dissolved in NN-dimethylformamide (50mL), stirred at 80°C under argon protection for 4 hours, cooled to room temperature, diluted with water, extracted with ethyl acetate, the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain a crude product. The crude product was purified by flash silica gel chromatography with ethyl acetate / petroleum ether = 1:3 (V / V) as the eluent to obtain a white solid (yield 80%), namely 2-cyclopropyl-7-methylamino-4-(pyridin-4-yl)-2H-indazole (compound 29).

[0241] 1 H NMR (400MHz, CDCl3, ppm) δ8.59(d,J=6.0Hz,2H),8.15(s,1H),7.54(d,J=4.8Hz,2H),7.30–7.26(m,1H),6.29(d, J=7.8Hz,1H),5.09(br,1H),3.97–3.87(m,1H),3.04(d,J=2.8Hz,3H),1.37–1.31(m,2H),1.17(q,J=7.2Hz,2H). 13 C NMR (100MHz, CDCl3, ppm) δ149.26,149.08,141.46,124.63,124.39,122.73,121.67,119.64,117.39,99.80,34.37,29.80,7.12.

[0242] Example 30 PDE4 assay

[0243] (1) Establish an in vitro screening method and model for PDE4D7 enzyme activity inhibition. Use time-resolved fluorescence resonance energy transfer to detect the inhibitory activity of PDE4D7 kinase. Use Rolipram as a control drug to determine its half inhibition rate IC in this model. 50 The results are consistent with the IC values ​​reported in many literatures. 50 The values ​​are similar, indicating that the screening model was successfully constructed.

[0244] (2) Dissolve the above compounds with DMSO to prepare a 10mM stock solution, continue to dilute with DMSO in a gradient, and add it to the final reaction system to ensure that the concentration of DMSO should be lower than 1%. The enzyme reaction system of PDE4D7 consists of PDE4D7 enzyme, BSA (bovine serum albumin), PDE4D7-specific fluorescent substrate FAM-cAMP, reaction buffer, etc. When all the components are mixed together, react at room temperature for 60 minutes. After the reaction is completed, add specific phosphate-binding antibodies and incubate at room temperature for another 60 minutes. Then use MD's SpectraMaxM5 multifunctional microplate reader to detect the fluorescence polarization signal, with an excitation wavelength of 485nm and an emission wavelength of 528nm. Substitute the values ​​into the following formula to calculate the activity percentage:

[0245] % activity = {(FP drug – FP background) / (FP enzyme – FP background)} × 100%

[0246] The compounds were tested for IC50 values, and the inhibition rates of the compounds at different concentrations on the enzyme were fitted with a dose-effect curve by nonlinear regression and normalization using Prism GraphPad software. The IC50 values ​​of the inhibitory activity of the compounds of the present invention on PDE4D7 are shown in Tables 1 and Figure 1 .

[0247] Table 1 Inhibitory activity of each example on PDE4D7 (IC 50 ,nM) a

[0248]

[0249] a **Indicates 100nM≤IC 50 <1000nM;

[0250] from Figure 1 As can be seen, the IC values ​​of compounds 10, 14, 15 and 17 for PDE4D7 50 The values ​​are 10.1 nM, 10.5 nM, 11.1 nM and 19.9 nM respectively.

[0251] Example 31 Cytotoxicity test of compound 10 and compound 17

[0252] Collect SH-SY5Y cells in the logarithmic growth phase for digestion, centrifugation and resuspension experimental operations. Adjust the concentration of the cell suspension and inoculate the cell suspension in a 96-well plate, with each well containing about 20,000 cells. The culture medium is a culture medium containing 1% fetal bovine serum, and the edge of the 96-well plate is filled with sterile PBS. Incubate in the incubator for 12 hours until the cells are completely attached. Draw off the original culture medium in the well, add culture medium without fetal bovine serum, and add different concentrations of compound 10 and 17 solutions to make the final drug concentrations in the wells 1, 3, 10, and 30 μmol / L, respectively. After 36 hours of incubation in the incubator, take out the 96-well plate treated with the experiment from the incubator, add 10% volume of thiazolyl blue solution (5 mg / mL) to each well, incubate in the incubator for 4 hours, carefully discard the culture medium, add DMSO (150 μL) solution to each well, shake the 96-well plate for 10 minutes using an enzyme reader, measure the absorbance value of each well at a wavelength of 570 nm using an enzyme reader, and then calculate the cell survival rate of each group. Cell survival rate = (experimental well - blank well) / (control well - blank well) × 100%, the results are as follows Figure 2 shown.

[0253] from Figure 2 It can be seen that the cell survival rate after adding different concentrations of compound 10 and compound 17 solutions is equivalent to the cell survival rate when no solution is added, indicating that compound 10 and compound 17 have no obvious toxicity to SH-SY5Y cells.

[0254] Example 32 Protective effects of compound 10 and compound 17 on rotenone-induced SH-SY5Y cell damage

[0255] Collect SH-SY5Y cells in the logarithmic growth phase for digestion, centrifugation and resuspension experimental operations. Adjust the concentration of the cell suspension and inoculate the cell suspension in a 96-well plate, with each well containing about 20,000 cells. The culture medium is a culture medium containing 1% fetal bovine serum, and the edge of the 96-well plate is filled with sterile PBS. Incubate in the incubator for 12 hours until the cells are completely attached. Draw off the original culture medium in the well, add culture medium without fetal bovine serum, and add different concentrations of compound 10 and 17 solutions to make the final drug concentrations in the wells 1, 3, 10, and 30 μmol / L, respectively. After 1 hour of incubation in the incubator, rotenone (ROT) was added to make the final concentration of rotenone in the culture medium 2μM. After incubation for 36 hours, the 96-well plate treated with the experiment was taken out of the incubator, and 10% volume of thiazolyl blue solution (5mg / mL) was added to each well, and the plate was incubated in the incubator for 4 hours. The culture medium was carefully discarded, and 150μLDMSO solution was added to each well. The 96-well plate was shaken for 10 minutes using an enzyme reader, and the absorbance value of each well was measured at a wavelength of 570nm using an enzyme reader, and then the cell survival rate of each group was calculated. Cell survival rate = (experimental well - blank well) / (control well - blank well) × 100%, the results are as follows Figure 3 shown.

[0256] from Figure 3 It can be seen that compound 17 has a protective effect on rotenone-induced SH-SY5Y cells at different concentrations.

[0257] Example 33 Protective effect of compound 10 on HT-22 cell injury in oxygen glucose deprivation / reoxygenation model (OGD / R)

[0258] The OGD / R model is a classic and recognized in vitro cell model for evaluating whether a compound has the ability to resist cerebral ischemia-reperfusion injury. HT-22 is a mouse hippocampal neuronal cell line used to replace primary cultured neurons. In this experiment, HT-22 cells were seeded in a 96-well plate. After overnight, the HT-22 cells were serum deprived for 1 hour, and the liquid in each group of wells was replaced with serum-free pure culture medium (the drug administration group was prepared and mixed in advance and then added with 0.625-20μM concentration of compound 10). Then the culture medium was aspirated and discarded, PBS was added and gently shaken and washed 3 times, and then aspirated and discarded, and replaced with sugar-free culture medium (the drug administration group was prepared and mixed in advance and then added with the corresponding concentration of compound 10, and the control group was replaced with high-sugar culture medium). Subsequently, the 96-well plate was placed in an anoxic chamber and closed (the control group was placed in a normal incubator), and the ventilation tube was opened to pass gas (95% nitrogen and 5% carbon dioxide mixed gas) for 5 minutes, and the ventilation rate was 10L / min. Finally, seal the ventilation tube, place in a 37°C incubator and culture until the modeling time is over (6 hours), take out the 96-well plate, replace the culture medium with normal culture medium, incubate for 24 hours, take out the 96-well plate after the experimental treatment from the incubator, add 10% volume of thiazolyl blue solution (5 mg / mL) to each well, place in the incubator and incubate for 4 hours, carefully discard the culture medium, add 150 μL DMSO solution to each well, shake the 96-well plate for 10 minutes using an enzyme reader, measure the absorbance value of each well at a wavelength of 570 nm using an enzyme reader, and then calculate the cell survival rate of each group. Cell survival rate = (experimental well - blank well) / (control well - blank well) × 100%, the results are as follows Figure 4 shown.

[0259] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An indazole compound or a pharmaceutically acceptable salt thereof, characterized in that: The indazole compound has the structure of formula (I): Among them, the R 1 is methoxy; R 2 is cyclopropyl or R 3 for The R 1 is difluoromethyl; R 2 is cyclopropyl; R 3 for The R 1 is ethoxy or methylamino; R 2 is cyclopropyl; R 3 for The R 1 is methoxy; R 2 is cyclopropyl; R 3 for The R 1 is difluoromethyl; R 2 is cyclopropyl; R 3 for The R 1 is methoxy; R 2 When it is cyclopropyl, R 3 for R 1 is difluoromethyl; R 2 When it is cyclopropyl, R 3 for 2. The method for preparing the indazole compound or a pharmaceutically acceptable salt thereof according to any one of claims 1, characterized in that: The preparation method of the indazole compound comprises the following steps: S1. Prepare the compound of formula (II); S2. Compound (II) and R 3 -X undergoes coupling reaction to obtain a compound represented by formula (I); X is B(OH)2, B(Pin)2 or H; The method for preparing the pharmaceutically acceptable salt of the indazole compound is to obtain the compound shown in (I) and then perform a salt-forming reaction to prepare the salt.

3. The method for preparing the indazole compound or a pharmaceutically acceptable salt thereof according to claim 2, characterized in that: The preparation method of the indazole compound is Compound is used as raw material and prepared according to the following reaction:

4. Use of the indazole compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 in the preparation of a medicament for treating phosphodiesterase 4-related diseases.

5. Use of the indazole compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 in the preparation of a medicament for treating inflammatory allergic diseases, autoimmune diseases, central nervous system diseases or organ diseases associated with ischemic reflow caused by heart failure, shock and cerebrovascular diseases.

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