Crystal form of tr-β selective agonist, preparation method, and use

Abstract

Disclosed in the present invention are a crystal form of a TR-β selective agonist, a preparation method, and a use. Specifically, disclosed are a crystal form of a compound represented by formula 1, a preparation method, and a use. The crystal form of the compound represented by formula 1 of the present invention has at least one of the following advantages: good physical and chemical stability, good solid-state properties, excellent solubility and process feasibility, and good bioactivity and safety. The preparation method for the compound represented by formula 1 of the present invention is a chiral synthesis method, is simple, convenient and efficient, and has good economic benefits.

Description

A crystalline form of a TR-beta selective agonist, methods of preparation and use TECHNICAL FIELD

[0001] The present invention relates to a crystalline form of a TR-beta selective agonist, methods of preparation and use. BACKGROUND

[0002] Thyroid hormones (triiodothyronine T3 and thyroxine) are important regulators of lipid homeostasis, thermogenesis and metabolic rate (Yen, 2001). The action of thyroid hormones stems from their ability to bind to specific nuclear receptors found in most cell types and tissues (Hulbert, 2000). Thyroid hormone receptors (THRs) are a class of ligand-dependent transcription factors with two major isoforms, receptors TR-alpha and TR-beta. The two receptors have different tissue-specific expression patterns. It is generally accepted that TR-alpha is mainly expressed in the heart, while TR-beta is mainly enriched in the liver. Since the liver is one of the most important target organs for thyroid hormones, THRs mediate lipid metabolism based on TR-beta in the liver.

[0003] THRs can activate gene expression by binding to DNA elements known as thyroid hormone response elements (TREs). It has been reported that the LDLR promoter contains regulatory elements similar to TREs and is responsive to T3 stimulation, but the specific nucleotide sequence and its location on the promoter have not been clearly described.

[0004] The beneficial metabolic effects of TR-beta activation include lowering low-density cholesterol by upregulating LDLR gene transcription, increasing liver metabolic rate, and reducing body weight. As a molecular target for treating dyslipidemia or nonalcoholic steatohepatitis (NASH), TR-beta is attracting increasing attention.

[0005] Nonalcoholic steatohepatitis (NASH) is a severe form of nonalcoholic fatty liver disease (NAFLD) caused by the accumulation of excess fat in the liver (hepatic steatosis). NAFLD is widely considered to be a manifestation of metabolic-related diseases in the liver, such as hyperlipidemia, obesity, type 2 diabetes, and insulin resistance. NASH is characterized by hepatic steatosis, inflammation, and hepatocellular ballooning with varying degrees of liver fibrosis. Most patients with NAFLD (70-90%) have simple steatosis, while 10-30% have aggressive NASH. Patients with NASH can progress to fibrosis (the first stage of scarring in the liver) and eventually cirrhosis, and can also lead to hepatocellular carcinoma or require liver transplantation. With the rising rate of obesity, the incidence of NAFLD and NASH is rapidly increasing worldwide. Before the first drug approved for the treatment of NASH (Resmetirom [MGL-3196]), the treatment of NAFLD and NASH was mainly lifestyle changes (diet and exercise) and bariatric surgery, as well as the off-label use of other drugs.

[0006] In the past two decades, much effort has been made to develop TR-β selective agonists that can distinguish between the beneficial effects on plasma and liver (lowering triglycerides and cholesterol) and the harmful effects on the heart, muscle, and bone.

[0007] In recent years, advances in molecular and structural biology have facilitated the design of new selective thyroid hormone mimics and agonists. These agonists exhibit TR subtype selective binding and / or liver and tissue selective uptake. Among them, Madrigal's Resmetirom (MGL-3196) is the most promising drug for the treatment of NASH, which has obtained the breakthrough therapy designation from the US FDA in March 2023 and has been successfully launched.

[0008] and Viking Therapeutics liver-targeted prodrug VK2809 (MB07811) are in clinical phase 2 trials.

[0009] CVI Pharmaceutical Technology (Shanghai) Co., Ltd. discovered a class of small molecule selective thyroid hormone beta receptor agonists in 2024, patent application number PCT / CN2024 / 099614, among which compound 48 and its chiral isomer compound 48-B (formula 1 in this patent) have strong agonistic effect on THR-beta, can effectively reduce low-density cholesterol, increase liver fat metabolism, and effectively treat NASH and NAFLD. The patent only discloses the biological activity of a few compounds and the method of obtaining a small amount of amorphous compound by liquid phase, and does not involve the crystal form research of its compounds and the preparation method of economic scale-up chemical synthesis.

[0010] It is known that most compounds exist in the form of polymorphism, and drug molecules also exist in two or more different crystal forms. The existence form and the number of polymorphic compounds cannot be predicted. Different crystal forms of a drug molecule may have significant differences in solubility, dissolution rate, melting point, bulk density, and physical and chemical stability, which may affect the physical and chemical properties of the drug when it is used in the human body through the crystal form of the drug substance and subsequent preparation process, thereby affecting the absorption, efficacy and safety of the drug.

[0011] SUMMARY

[0012] In order to overcome the problem of single type of thyroid hormone beta selective agonist in the prior art and poor stability, solubility or hygroscopicity, the present application provides a crystal form of TR-beta selective agonist, a preparation method and application. The crystal form of the TR-beta selective agonist has at least one of the following advantages: good physical and chemical stability, good solid state, excellent solubility and process feasibility, and good biological activity and safety. The preparation method has the advantages of short synthesis steps, no need for special separation and purification method, avoidance of using instrument separation means, high yield, low cost and excellent economic benefit.

[0013] The present application provides a crystal form A of a compound represented by formula 1, which has characteristic diffraction peaks at the following 2θ angles in the X-ray powder diffraction pattern (XRPD pattern): 9.70°±0.20°, 13.53°±0.20°, 16.62°±0.20°, 19.51°±0.20°, 21.44°±0.20° and 23.02°±0.20°.

[0014] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles with diffraction peaks at one or more of the following 2θ angles: 8.77°±0.20°, 12.09°±0.20°, 15.54°±0.20°, 17.62°±0.20°, 18.01°±0.20°, and 24.11°±0.20°.

[0015] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles with diffraction peaks at one or more of the following 2θ angles: 8.77°±0.20°, 12.09°±0.20°, 15.54°±0.20°, 17.62°±0.20°, 18.01°±0.20°, and 24.11°±0.20°.

[0016] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles with diffraction peaks at one or more of the following 2θ angles: 8.77°±0.20°, 12.09°±0.20°, 15.54°±0.20°, 17.62°±0.20°, 18.01°±0.20°, and 24.11°±0.20°.

[0017] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has a thermogravimetric analysis pattern showing a weight loss of 0.1% at 120°C.

[0018] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has a differential scanning calorimetry pattern with an endothermic peak at 307.7°C±2.0°C.

[0019] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has a differential scanning calorimetry pattern substantially as shown in Figure 2.

[0020] In a preferred embodiment, the crystalline Form A of the compound of Formula 1 has a thermogravimetric analysis pattern substantially as shown in Figure 3.

[0021] The present application provides a crystalline Form D of the compound of Formula 1 having an X-ray powder diffraction pattern (XRPD pattern) with characteristic diffraction peaks at the following 2θ angles: 8.22°±2.0°, 12.43°±2.0°, 20.24°±2.0°, and 24.52°±2.0°.

[0022] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles with diffraction peaks at one or more of the following 2θ angles: 9.16°±2.0°, 9.44°±2.0°, 16.24°±2.0°, 16.52°±2.0°, 16.99°±2.0°, and 27.50°±2.0°.

[0023] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles with diffraction peaks at one or more of the following 2θ angles: 9.16°±2.0°, 9.44°±2.0°, 16.24°±2.0°, 16.52°±2.0°, 16.99°±2.0°, and 27.50°±2.0°.

[0024] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has an X-ray powder diffraction pattern, expressed in terms of 2θ angles, substantially as shown in FIG. 10.

[0025] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has a thermogravimetric analysis pattern showing a weight loss of 1.42% at 120°C.

[0026] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has a differential scanning calorimetry pattern having three endothermic peaks at 25.6°C ± 2.0°C, 90°C ± 2.0°C and 311.6°C ± 2.0°C, and one exothermic peak at 253.0°C ± 2.0°C.

[0027] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has a differential scanning calorimetry pattern substantially as shown in FIG. 11.

[0028] In a preferred embodiment, the crystalline Form D of the compound of Formula 1 has a thermogravimetric analysis pattern substantially as shown in FIG. 12. The present application also provides a preparation method of the crystalline Form A of the compound of Formula 1, comprising the following steps:

[0029] adding a solution of the compound of Formula 1 and a solvent to water to crystallize the compound of Formula 1 to obtain the crystalline Form A of the compound of Formula 1;

[0030] wherein the solvent is an amide solvent.

[0031] In the present application, the amide solvent is a conventional amide solvent in the art, and in a preferred embodiment, the amide solvent is N,N-dimethylformamide (DMF) and / or dimethylacetamide (DMAc).

[0032] In a preferred embodiment, the compound of Formula 1 is an amorphous compound of Formula 1 or a D crystalline form of the compound of Formula 1.

[0033] In a preferred embodiment, the mass-to-volume ratio of the compound of Formula 1 to the solvent is 0.01-0.3 g / mL, for example, 0.1-0.16 g / mL.

[0034] In a preferred embodiment, the volume ratio of water to the solvent is 1:(1-30), for example, 1:(1-12.5).

[0035] In a preferred embodiment, the water is added dropwise.

[0036] In a preferred embodiment, when the compound of Formula 1 is a D crystalline form of the compound of Formula 1, the mass-to-volume ratio of the compound of Formula 1 to the solvent is 0.16 g / mL.

[0037] In a preferred embodiment, when the compound of formula 1 is the crystalline form D of the compound of formula 1, the volume ratio of water to solvent is 1:12.5.

[0038] In a preferred embodiment, the crystallization can be followed by a post-treatment, which can include stirring, filtration and drying.

[0039] In a preferred embodiment, in the post-treatment, the stirring can be performed for 24-72h, such as 48h, before filtration.

[0040] In a preferred embodiment, in the post-treatment, the drying is performed by vacuum drying.

[0041] In a preferred embodiment, in the post-treatment, the drying is performed at a temperature of 45-250°C, such as 50-220°C.

[0042] In a preferred embodiment, in the post-treatment, the drying is performed for a time period of 0.4-50h, such as 0.5-18h.

[0043] The present application also provides a method for preparing the crystalline form D of the compound of formula 1, comprising the following steps:

[0044] The suspension of the compound of formula 1 and the alcoholic solvent is crystallized to obtain the crystalline form D of the compound of formula 1.

[0045] In a preferred embodiment, the compound of formula 1 is an amorphous compound.

[0046] In the present application, the alcoholic solvent is a conventional alcoholic solvent in the art, and in a preferred embodiment, the alcoholic solvent is methanol.

[0047] In a preferred embodiment, the mass volume ratio of the compound of formula 1 to the alcoholic solvent is 0.01-0.3g / mL, such as 0.1mg / mL.

[0048] In a preferred embodiment, the crystallization of the suspension is performed at a temperature of 30-70°C, such as 50°C.

[0049] In a preferred embodiment, the crystallization of the suspension is performed for a time period of 24-72h, such as 48h.

[0050] The present application also provides a use of a substance A in the preparation of a THR-β selective agonist, wherein the substance A is the crystalline form A of the compound of formula 1 or the crystalline form D of the compound of formula 1 as described above (the substance A is an active ingredient); and the substance A can be in a therapeutically effective amount.

[0051] In the application, preferably, the THR-β selective agonist can be used in vivo in a mammal; it can also be used in vitro, mainly for experimental purposes, such as providing a standard or control sample for comparison, or being prepared into a kit according to the conventional method in the art, to provide a rapid detection of the effect of the compound in selectively agonizing THR-β.

[0052] The application also provides a use of a substance A in the preparation of a medicament, which can be a medicament for treating and / or preventing metabolic diseases or cardiovascular diseases, preferably non-alcoholic steatohepatitis (NASH), liver steatosis, hyperlipidemia, thyroid diseases, obesity, hypercholesterolemia and diabetes, more preferably obesity, hyperlipidemia, hypercholesterolemia and diabetes, and preferably hypothyroidism and thyroid cancer, or cardiovascular diseases, preferably atherosclerosis; or, the medicament can be a medicament for treating and / or preventing diseases mediated or associated with selective agonizing of THR-β, such as a medicament for treating and / or preventing metabolic diseases and cardiovascular diseases, preferably liver steatosis, non-alcoholic steatohepatitis (NASH), obesity, atherosclerosis, hyperlipidemia and thyroid diseases, and preferably hypothyroidism and thyroid cancer; the substance A is the crystalline form A of the compound of formula 1 or the crystalline form D of the compound of formula 1 as described above; the substance A can be in a therapeutically effective amount.

[0053] The application also provides a method for selectively agonizing THR-β, which comprises administering a therapeutically effective amount of a substance A to a patient; the substance A is the crystalline form A of the compound of formula 1 or the crystalline form D of the compound of formula 1 as described above (the substance A is an active ingredient); the substance A can be in a therapeutically effective amount.

[0054] The application also provides a method for treating and / or preventing metabolic related diseases, which comprises administering a therapeutically effective amount of a substance A to a patient; the substance A is the crystalline form A of the compound of formula 1 or the crystalline form D of the compound of formula 1 as described above; the metabolic related diseases are preferably non-alcoholic steatohepatitis (NASH), obesity, hyperlipidemia, hypercholesterolemia and diabetes.

[0055] The application also provides a preparation method of the compound of formula 1, which comprises the following steps:

[0056] The compound of formula 1 is obtained after the compound of formula 9 and an inorganic base are reacted in a solvent.

[0057] In a preferred embodiment, the solvent is a polar solvent, which is a polar solvent conventional in the art, and is preferably one or more of methanol, ethanol, tetrahydrofuran or acetic acid, such as acetic acid.

[0058] In a preferred embodiment, the mass volume ratio of the compound of formula 9 and the solvent is 1: (3-10) g / mL, for example 1:5 g / mL.

[0059] In the present application, the inorganic base is a conventional inorganic base in the art, and in a preferred embodiment, the inorganic base is one or more of sodium hydroxide, potassium carbonate and sodium acetate, for example sodium acetate.

[0060] In a preferred embodiment, the molar ratio of the compound of formula 9 and the inorganic base is 1: (1-5), for example 1:2.

[0061] In a preferred embodiment, the temperature of the reaction is 30-70°C, for example 40°C.

[0062] In a preferred embodiment, the reaction is followed by a post-treatment step, which includes extraction, drying, filtration and concentration.

[0063] In a preferred embodiment, the method for preparing the compound of formula 1 further comprises the following steps:

[0064] The compound of formula 7 is diazotized in a solvent in the presence of an inorganic acid and a nitrite or nitrite ester, and then coupled with the compound of formula 8 in the presence of a base to obtain the compound of formula 9.

[0065] In the present application, the inorganic acid is a conventional inorganic acid in the art, and in a preferred embodiment, the inorganic acid is concentrated hydrochloric acid and / or concentrated sulfuric acid, for example concentrated hydrochloric acid.

[0066] In a preferred embodiment, the molar ratio of the compound of formula 7 and the nitrite or nitrite ester is 1: (1-5), for example 1:2.

[0067] In a preferred embodiment, the nitrite ester is isoamyl nitrite or tert-butyl nitrite, for example isoamyl nitrite.

[0068] In a preferred embodiment, the nitrite is an aqueous solution of sodium nitrite, potassium nitrite or an alcoholic solution of sodium nitrite, potassium nitrite, and the alcoholic solution can be methanol.

[0069] In a preferred embodiment, the nitrite ester is a mixed solution of nitrite ester and polar solvent, and the polar solvent can be one or more of methanol, tetrahydrofuran and acetonitrile, for example acetonitrile.

[0070] In a preferred embodiment, the temperature of the diazotization reaction is 0-5°C.

[0071] In a preferred embodiment, the molar ratio of the compound of formula 7 to the compound of formula 8 is 1 : (1-5), for example 1 :2.

[0072] In a preferred embodiment, the temperature of the coupling reaction is 0-5 °C.

[0073] In a preferred embodiment, the method for preparing the compound of formula 1 further comprises the following steps:

[0074] In a solvent, the compound of formula 6 is subjected to a deprotection reaction under the action of an inorganic base and water or other deprotection group conditions to obtain the compound of formula 7;

[0075] R 2 is an N protecting group, for example -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts.

[0076] In a preferred embodiment, the solvent is an alcohol solvent, for example methanol.

[0077] In a preferred embodiment, the mass volume ratio of the solvent to the compound of formula 6 is 1 : (3-10) g / mL, for example 1 :6.7 g / mL.

[0078] In a preferred embodiment, the molar ratio of the compound of formula 6 to the inorganic base is 1 : (2-7), for example 1 :4.6.

[0079] In a preferred embodiment, the temperature of the deprotection reaction is 20-120 °C, for example 100 °C.

[0080] In a preferred embodiment, after the deprotection reaction, a post-treatment is further included, and the post-treatment step can be extraction, drying, filtration and concentration.

[0081] In a preferred embodiment, the method for preparing the compound of formula 1 further comprises the following steps:

[0082] In a solvent, the compound of formula 5 is subjected to a deprotection reaction under the action of an acid or other deprotection group conditions to obtain the compound of formula 6;

[0083] R 2 is an N protecting group, for example -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts;

[0084] R 1 is an N protecting group, for example -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc.

[0085] In a preferred embodiment, the solvent is an ether solvent, which is a conventional ether solvent in the art, such as dioxane.

[0086] In a preferred embodiment, the mass volume ratio of the solvent and the compound of formula 5 is 1 : (3-10) g / mL, such as 1 : 6.7 g / mL.

[0087] In a preferred embodiment, the acid is an organic acid or an inorganic acid, preferably one or more of TFA, acetic acid and hydrochloric acid, such as hydrochloric acid.

[0088] In a preferred embodiment, the deprotection reaction is further followed by a work-up, which can be concentration, pH adjustment and filtration.

[0089] In a preferred embodiment, the method for preparing the compound of formula 1 further comprises the following steps:

[0090] In a solvent, under the action of a ruthenium catalyst or a rhodium catalyst and an organic phosphine or an organic amine ligand, the compound of formula 4 is subjected to a reduction reaction to obtain the compound of formula 5 under the action of hydrogen or other reducing agents.

[0091] In a preferred embodiment, the solvent is an alcohol solvent, such as methanol.

[0092] In a preferred embodiment, the mass volume ratio of the solvent and the compound of formula 4 is 1 : (3-30) g / mL, such as 1 : 25 g / mL.

[0093] In a preferred embodiment, the ruthenium catalyst is Ru(methylallyl)2(COD) and / or [Ru(p-cymene)Cl2]2, such as [Ru(p-cymene)Cl2]2.

[0094] In a preferred embodiment, the rhodium catalyst is Rh(NBD)2BF4 and / or Rh(COD)2BF4.

[0095] In a preferred embodiment, the organic phosphine ligand is 1,1'-binaphthalene-2,2'-diphenylphosphine (R-BINAP).

[0096] In a preferred embodiment, the molar ratio of the catalyst and the organic phosphine ligand is 1 : (1-2.5), such as 1 : 2.

[0097] In a preferred embodiment, the molar ratio of the catalyst and the compound of formula 4 is 0.01-0.2, such as 0.1.

[0098] In a preferred embodiment, the reaction is replaced with an inert gas, which can be nitrogen.

[0099] In a preferred embodiment, the temperature of the reduction reaction is 20-60°C.

[0100] In a preferred embodiment, the deprotection reaction is further followed by a work-up, which can be filtration, concentration and column chromatography purification.

[0101] In a preferred embodiment, the method for preparing the compound of Formula 1 further comprises the following steps:

[0102] reacting the compound of Formula 3 with the compound of Formula 2 in a solvent in the presence of a palladium catalyst and a base to obtain compound 4;

[0103] R 2 is an N protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts;

[0104] R 1 is an N protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc.

[0105] In a preferred embodiment, the solvent is a mixture of an ether solvent and water, the ether solvent is a conventional ether solvent in the art, such as dioxane; the volume ratio of the ether solvent to water can be (1-5): 1, such as 2: 1; preferably, the solvent is a mixture of dioxane and water with a volume ratio of 2: 1.

[0106] In a preferred embodiment, the volume ratio of the solvent to the compound of Formula 2 is 1: (3-20) g / mL, such as 1: 15 g / mL.

[0107] In a preferred embodiment, the molar ratio of the compound of Formula 2 to the compound of Formula 3 is 1-1.5, such as 1.25.

[0108] In a preferred embodiment, the molar ratio of the palladium catalyst to the compound of Formula 2 is 0.01-0.2, such as 0.1.

[0109] In a preferred embodiment, the molar ratio of the compound of Formula 2 to the base is 1: (2-5), such as 1:3.

[0110] In a preferred embodiment, the palladium catalyst is a conventional palladium catalyst in the art, preferably Pd(dppf)Cl2.

[0111] In a preferred embodiment, the base is a base conventional in the art, preferably potassium phosphate.

[0112] In a preferred embodiment, the reaction is replaced with an inert gas, which can be nitrogen.

[0113] In a preferred embodiment, the temperature of the reaction is 100-160°C.

[0114] In a preferred embodiment, the reaction is further followed by a post-treatment, which post-treatment step comprises extraction, drying, filtration, concentration and column chromatography purification.

[0115] In a preferred embodiment, the method for preparing the compound of formula 1 further comprises the following steps:

[0116] In a solvent, the compound of formula 3-1 is reacted with bis[(pinacolato)boron]methylane, an inorganic base and a palladium catalyst to form the compound of formula 3.

[0117] R 1 is a N protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, and for example -Boc.

[0118] In a preferred embodiment, the solvent is a polar organic solvent, which polar organic solvent is a polar organic solvent conventional in the art, preferably an ether solvent, such as dioxane.

[0119] In a preferred embodiment, the mass to volume ratio of the solvent to the compound of formula 3-1 is 1:(3-10) g / mL, for example 1:5 g / mL.

[0120] In a preferred embodiment, the molar ratio of the compound of formula 3-1 to the bis[(pinacolato)boron]methylane is 1:(1-2), for example 1:1.1.

[0121] In a preferred embodiment, the inorganic base is an inorganic base conventional in the art, such as potassium hydroxide.

[0122] In a preferred embodiment, the palladium catalyst is a palladium catalyst conventional in the art, such as Pd[P(t-Bu)3]2.

[0123] In a preferred embodiment, the molar ratio of the palladium catalyst to the compound of formula 3-1 is 0.01-0.2, preferably 0.01-0.1, for example 0.04.

[0124] In a preferred embodiment, the reaction is replaced with an inert gas, which can be nitrogen.

[0125] In a preferred embodiment, the reaction is followed by work-up, which comprises extraction, drying, filtration, concentration and column chromatography purification.

[0126] The present application also provides a compound as shown in the following formula 3:

[0127] R 2 is an N-protecting group, for example -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, and for example -Ts;

[0128] R 1 is an N-protecting group, for example -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, and for example -Boc.

[0129] The present application also provides a preparation method of the compound as shown in the above formula 3, which comprises the following steps:

[0130] reacting the compound as shown in the formula 3-1 with the compound as shown in the formula 3 in a solvent in the presence of bis[(pinacolato)boron]methyl, an inorganic base and a palladium catalyst;

[0131] R 1 is an N-protecting group, for example -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, and for example -Boc.

[0132] In a preferred embodiment, the preparation method of the compound as shown in the formula 3 is operated and the reaction conditions are as described above.

[0133] The present application also provides a preparation method of the compound as shown in the above formula 4, which comprises the following steps:

[0134] reacting the compound as shown in the formula 3 with the compound as shown in the formula 2 in a solvent in the presence of a palladium catalyst and a base to obtain the compound 4;

[0135] R 2 is an N-protecting group, for example -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, and for example -Ts;

[0136] R 1 is an N-protecting group, for example -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, and for example -Boc.

[0137] In a preferred embodiment, the preparation method of the compound as shown in the formula 4 is operated and the reaction conditions are as described above.

[0138] The present application also provides a method for preparing the compound of formula 5 as described above, comprising the following steps:

[0139] The compound of formula 4 is subjected to a reduction reaction under the action of a ruthenium catalyst or a rhodium catalyst and an organic phosphine or an organic amine ligand in a solvent under the action of hydrogen or other reducing agents to obtain the compound of formula 5.

[0140] In a certain preferred embodiment, the operation and reaction conditions of the method for preparing the compound of formula 5 are as described above.

[0141] The present application also provides a method for preparing the compound of formula 6 as described above, comprising the following steps:

[0142] The compound of formula 5 is subjected to a deprotection reaction under the action of an acid or other deprotection group conditions in a solvent to obtain the compound of formula 6;

[0143] R 2 is an N protecting group, for example -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, and for example -Ts;

[0144] R 1 is an N protecting group, for example -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, and for example -Boc.

[0145] In a certain preferred embodiment, the operation and reaction conditions of the method for preparing the compound of formula 6 are as described above.

[0146] The present application also provides a method for preparing the compound of formula 7 as described above, comprising the following steps:

[0147] The compound of formula 6 is subjected to a deprotection reaction under the action of an inorganic base and water or other deprotection group conditions in a solvent to obtain the compound of formula 7;

[0148] R 2 is an N protecting group, for example -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, and for example -Ts.

[0149] In a certain preferred embodiment, the operation and reaction conditions of the method for preparing the compound of formula 7 are as described above.

[0150] The present application also provides a method for preparing the compound of formula 9 as described above, comprising the following steps:

[0151] The compound of formula 7 is diazotized in a solvent in the presence of an inorganic acid and sodium nitrite or nitrite ester, and then coupled with a compound of formula 8 in the presence of a base to obtain a compound of formula 9.

[0152] In a certain preferred embodiment, the operations and reaction conditions of the method for preparing the compound of formula 9 are as previously described.

[0153] Definitions of terms

[0154] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which the claimed subject matter belongs. If there is an inconsistency between the definitions of terms as provided in this section and the usage of terms in the remainder of this disclosure, the usage of terms in the remainder of this disclosure shall prevail.

[0155] The term "treatment" refers to eliminating the cause of the disease or alleviating the symptoms.

[0156] The term "prevention" refers to reducing the risk of developing a disease.

[0157] The term "patient" refers to any animal, typically a mammal, such as a human, in need of treatment or prevention of a disease. Mammals include, but are not limited to, cows, horses, sheep, pigs, cats, dogs, mice, rats, rabbits, guinea pigs, monkeys, humans, and the like.

[0158] The term "therapeutically effective amount" refers to the amount of a compound administered to a patient that is sufficient to effectively treat a disease. The therapeutically effective amount will vary depending on the type of compound, the type of disease, the severity of the disease, the age of the patient, and the like, but can be adjusted by one of skill in the art as appropriate.

[0159] Unless otherwise indicated, the present application employs conventional methods of mass spectroscopy, elemental analysis, and the like, and the various substituents and reaction conditions can be in accordance with conventional methods of organic synthesis.

[0160] Unless otherwise indicated, the present application employs standard nomenclature and standard laboratory procedures of analytical chemistry, organic synthesis, and optics. In certain instances, standard techniques are used for chemical synthesis, chemical analysis.

[0161] The following definitions shall apply unless otherwise indicated. For the purposes of the present application, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, and the "Handbook of Chemistry and Physics", 75thEd., 1994. Additionally, general principles of organic chemistry are described in "Organic Chemistry", Thomas Sorrell, University Science Books, Sausalito: 1999, and "March's Advanced Organic Chemistry", by Michael B. Smith and Jerry March, John Wiley & Sons, New York: 2007, the entire contents of which are incorporated herein by reference.

[0162] In the present application, "room temperature" means "20-40°C".

[0163] TLC in the present patent means thin layer chromatography, which is generally used for the intermediate control point of organic chemical synthesis and reaction, for detecting the progress of reaction or the end point of reaction. If not otherwise specified, the glass silica gel thin layer chromatography plate is used, and the mobile phase is a mixture of ethyl acetate and petroleum ether, unless otherwise specified. The solvent ratio is generally adjusted according to the polarity difference between the target compound and the raw material.

[0164] Post-treatment in the present patent means the means for separating the target product from the reaction system after the reaction reaches the end point. Generally, an appropriate amount of water or other low-solubility solvent of the reaction product is added, the target compound is extracted with an organic solvent and washed, and then dried, concentrated and purified to obtain the intermediate product.

[0165] Silica gel column chromatography purification in the present patent is generally used for the purification of reaction intermediates. The 200-400 mesh silica gel powder is placed in a glass column, and the material is eluted by silica gel column chromatography and mobile phase to separate the target compound and impurities. The mobile phase solution rich in the target intermediate is distilled and concentrated to obtain the target intermediate with high purity.

[0166] Preparative liquid chromatography purification in the present patent generally uses a preparative liquid chromatograph. Through the appropriate method developed by the analyst, the component rich in the intermediate or the final target product with high purity is obtained by elution with the mobile phase (usually the mobile phase is acetonitrile / water). The mobile phase solution is distilled and concentrated to remove acetonitrile and retain water, and the water is freeze-dried to obtain the solid target intermediate or final target product.

[0167] 1 ​HNMR refers to nuclear magnetic resonance hydrogen spectrum, which is determined by using a Bruker instrument (200-500 MHz, usually 400 MHz), and the chemical shift is expressed by ppm. Deuterated chloroform or deuterated DMSO is usually used as a solvent, sometimes an internal standard TMS is used for calibration, and sometimes a small amount of non-deuterated chloroform peak or DMSO peak in deuterated chloroform or deuterated DMSO is directly used as a calibration. The peak shape in nuclear magnetic resonance is expressed as s = singlet, d = doublet, t = triplet, m = multiplet, dd = double doublet, and dt = double triplet. The unit of coupling constant is usually Hz.

[0168] Mass spectrum, usually determined by LC-MS, ionization is usually ESI, usually positive ion, a few negative ions are specially indicated. All melting point data are not corrected.

[0169] On the basis of common sense in the art, the above-mentioned preferred conditions can be combined arbitrarily, that is, the preferred examples of the present application are obtained.

[0170] The reagents and raw materials used in the present application are commercially available.

[0171] The positive progress effect of the present application is that the crystal form A of the THR-β agonist and the crystal form D of the THR-β agonist have good physical and chemical stability, good solid state properties, excellent solubility and process feasibility, meet the overall requirements of drug suitability, and can have good selective activation of THR-β. The crystal form A discovered in the present application shows excellent tissue distribution characteristics in in vivo experiments of mouse, rat, dog and cynomolgus monkey and other species, and shows high intensity of cholesterol lowering and treatment of NASH in preclinical animal models of NASH and hyperlipidemia. The compound has no significant inhibition effect on hERG and CYP enzyme, and is metabolically stable in human, rat, mouse, dog and monkey hepatocytes. The preparation method of the target compound disclosed in the present application introduces the target chiral center with high stereoselectivity by chiral asymmetric catalysis, avoids the use of instruments or other conventional means for splitting isomers to introduce chiral center, has lower cost, is more environmentally friendly, and has higher atom utilization efficiency to obtain intermediates and final target compounds. BRIEF DESCRIPTION OF DRAWINGS

[0172] Figure 1: XRPD spectrum of crystal form A

[0173] Figure 2: DSC spectrum of crystal form A

[0174] Figure 3: TGA spectrum of crystal form A

[0175] Figure 4: XRPD spectrum of crystal form A before and after moisture absorption

[0176] Figure 5: XRPD pattern of Form B

[0177] Figure 6: DSC pattern of Form B

[0178] Figure 7: TGA pattern of Form B

[0179] Figure 8: XRPD pattern of Form C

[0180] Figure 9: DSC pattern of Form C

[0181] Figure 10: XRPD pattern of Form D

[0182] Figure 11: DSC pattern of Form D

[0183] Figure 12: TGA pattern of Form D

[0184] Figure 13: DSC pattern of Form E

[0185] Figure 14: XRPD pattern of Form E

[0186] Figure 15: Dose-dependent reduction of serum TC and LDL-C by amorphous Compound 1;

[0187] Figure 16: Determination of amorphous Compound 1 concentration in tissues;

[0188] Figure 17: qRT-PCR analysis of Me1 mRNA levels in liver and heart tissues.

[0189] Figure 18: Compound amorphous Compound 1 effectively reduced liver TG (A) and TC (B) levels and NASH score (C) at lower doses than MGL-3196 in a high-fat diet (HFD) plus carbon tetrachloride (CCl4)-induced NASH mouse model.

[0190] Figure 19: Determination of Compound amorphous Compound 1 concentration in liver and serum of NASH mouse model. DETAILED DESCRIPTION

[0191] The present application is further illustrated by the following examples, which in no way should be construed as limiting the scope of the present application.

[0192] The experimental methods in the following examples, where no specific conditions are indicated, were carried out according to conventional methods and conditions, or as selected according to the manufacturer's instructions.

[0193] Crystal form related testing equipment, instruments:

[0194] ​1.1 X-ray powder diffractometer (XRPD)

[0195] 1.2 Differential scanning calorimeter (DSC) and Thermal gravimetric analyzer (TGA)

[0196] 1.3 Dynamic vapor sorption (DVS)

[0197] 1.4 Hygroscopicity evaluation is classified as follows: Note: ΔW% represents the weight gain of the test sample under 25±1°C and 80±2% RH.

[0198] 1.5 High performance liquid chromatography analysis method:

[0199] Method for preparing amorphous compound 1 (compound 48-B):

[0200] First step: Synthesis of compound 48-1: 3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6- carbonitrile

[0201] Dissolve 6-bromo-1,2,4-triazine-3,5(2H,4H)-dione (5.00 g, 26.0 mmol) in DMSO (10 mL) and add cuprous cyanide (7.00 g, 78.1 mmol). The reaction solution is replaced with nitrogen and heated to 110°C for 2 hours using a microwave reactor until the reaction is complete. Add water (50 mL) to the reaction solution and extract three times with ethyl acetate (25 mL). Separate the organic phase and wash with brine (25 mL), dry over anhydrous sodium sulfate, and filter. Concentrate the filtrate and purify the residue by reverse phase C18 column chromatography (mobile phase, acetonitrile / water, 0-40%) to obtain compound 48-1: 3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6-carbonitrile (700 mg, yield 20%) as a light yellow solid.

[0202] LC-MS: [ESI] [M+H] + = 139.1.

[0203] Second Step: Synthesis of compound 48-2: 2-(3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)-3,5-dioxo-2,3,4,5- tetrahydro-1,2,4-triazine-6-carbonitrile

[0204] Compound 21-7: 3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1-trifluoropropyl-2-yl)-1H- pyrrolo[3,2-b]pyridin-5-yl)methyl)phenol trifluoromethanesulfonate (50 mg, 0.08 mmol), compound 48-1: 3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6-carbonitrile (54 mg, 0.39 mmol), bis-benzylidene-[2,3,4,5-tetramethyl-6-(2,4,6-triisopropylbenzyl)phenyl]phosphane (8 mg, 0.02 mmol), potassium carbonate (33 mg, 0.24 mmol) and Pd2(dba)3(11 mg, 0.01 mmol) were dissolved in t-butanol (3 mL). The reaction was purged with nitrogen and heated to 110 °C under microwave conditions for 2 hours until the reaction was complete. The reaction was added to water (5 mL) and extracted with ethyl acetate (5 mL) three times. The organic phase was separated and combined and washed with brine (5 mL), dried over anhydrous sodium sulfate, filtered. The filtrate was concentrated and the residue was purified by silica gel column chromatography (mobile phase, ethyl acetate / petroleum ether, 0-50%) to give compound 48-2: 2-(3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1-trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)-3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6-carbonitrile (30 mg, yield 61%) as a yellow solid.

[0205] LC-MS: [ESI] [M+H] + = 623.4.

[0206] Third Step: Synthesis of 48-A-1 and 48-B-1: a pair of chiral enantiomers - 2-(3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1-trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)-3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6-carbonitrile

[0207] Chiral separation (Chiral prep column: Daicel ChiralCel OJ, 40 mm I.D. x 250 nm, 10 pm; mobile phase: mobile phase A: carbon dioxide, mobile phase B: methanol; gradient: 35% mobile phase B / 65% mobile phase A; flow rate: 120 mL / min, 2.01 h; column temperature: 25 °C) of compound 48-2: 2-(3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)-3,5-dioxo-2,3,4,5- tetrahydro-1,2,4-triazine-6-carbonitrile (1.60 g, 2.57 mmol) afforded two pairs of chiral enantiomers as white solids:

[0208] 48-A-1 (RT = 5.466 min, 450 mg, 28% yield), ee: 100%, (Chiral column: Daicel ChiralPAK-OJ 100 x 3.0 mm 3 pm; mobile phase: mobile phase A: carbon dioxide, mobile phase B: methanol; gradient: 15% mobile phase B / 85% mobile phase A; flow rate: 2 mL / min, 8.0 min; column temperature: 35 °C).

[0209] and 48-B-1 (RT = 4.570 min: 470 mg, 29% yield). ee: 100%, (Chiral column: Daicel ChiralPAK-OJ 100 x 3.0 mm 3 pm; mobile phase: mobile phase A: carbon dioxide, mobile phase B: methanol; gradient: 15% mobile phase B / 85% mobile phase A; flow rate: 2 mL / min, 8.0 min: column temperature: 35 °C).

[0210] Fourth step: 48-A and 48-B: synthesis of a pair of chiral enantiomers - 2-(3,5-dimethyl-4-((3-(1,1,1-trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)-3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6-carbonitrile

[0211] The above chiral compound 48-A-1 (350 mg, 0.526 mmol) was dissolved in DMF (2 mL) and potassium hydroxide (315 mg, 5.62 mmol) was added. The reaction was warmed to 50 °C and stirred for 2 hours until the reaction was complete. The reaction was concentrated to dryness under reduced pressure to give a residue. The residue was purified by preparative chromatography (flow rate: 70 mL / min; column temperature: 25 °C; column: Ultimate XB-C18, 50*250 mm, 10 pm (P ARP-02); mobile phase: MeCN:H2O (0.1% NH4HCO3)) to give compound 48-A (amorphous) as a white solid (100 mg, yield 38%).

[0212] The above chiral compound 48-B-1 (400 mg, 0.643 mmol) was dissolved in DMF (2 mL) and potassium hydroxide (360 mg, 6.43 mmol) was added. The reaction was warmed to 50 °C and stirred for 2 hours until the reaction was complete. The reaction was concentrated to dryness under reduced pressure to give a residue. The residue was purified by preparative chromatography (flow rate: 70 mL / min; column temperature: 25 °C; column: Ultimate XB-C18, 50*250 mm, 10 pm (P ARP-02); mobile phase: MeCN:H2O (0.1% NH4HCO3)) to give compound 48-B (amorphous) as a white solid (40 mg, yield 13%).

[0213] Characterization data of compound 48-A:

[0214] Optical rotation: [a] = +16° (ethanol, c = 0.075 g / 100 mL, l = 589 nm, T = 25 °C)

[0215] LC-MS: [ESI] [M+H] + = 469.2.

[0216] Chiral purity: ee: 99.46%, RT = 9.423 min (Chiral column: Regis Pack-WHELK_RR_100x4.6 mm_5 pm; mobile phase: mobile phase A: carbon dioxide, mobile phase B: methanol; gradient: 20% mobile phase B / 80% mobile phase A; flow rate: 2 mL / min, 15 min; column temperature: 35 °C).

[0217] 1H NMR (400 MHz, DMSO-d6) δ 11.26 (s, 1H), 7.62 (t, J = 8.4 Hz, 2H), 7.12 (s, 2H), 6.70 (d, J = 8.4 Hz, 1H), 4.23 (s, 2H), 4.01 - 4.08 (m, 1H) 2.34 (s, 6H), 1.53 (d, J = 7.6 Hz, 3H) ppm.

[0218] Characterization data of compound 48-B:

[0219] Optical rotation: [a] = -9.3° (ethanol, c = 0.075 g / 100 mL, λ = 589 nm, T = 25 °C)

[0220] LC-MS: [ESI] [M+H] + = 469.2.

[0221] Chiral purity: ee: 99.70%, RT = 10.052 min (Chiral column: Regis Pack-WHELK_RR_100x4.6 mm_5 μm; mobile phase: mobile phase A: carbon dioxide, mobile phase B: methanol; gradient: 20% mobile phase B / 80% mobile phase A; flow rate: 2 mL / min, 15 min; column temperature: 35 °C).

[0222] 1 H NMR (400 MHz, DMSO-d6) δ 11.26 (s, 1H), 7.62 (t, J = 8.4 Hz, 2H), 7.12 (s, 2H), 6.70 (d, J = 8.4 Hz, 1H), 4.23 (s, 2H), 4.01 - 4.08 (m, 1H) 2.34 (s, 6H), 1.53 (d, J = 7.6 Hz, 3H) ppm.

[0223] Preparation of compound 21-7

[0224] First step: synthesis of compound 21-1 : 5-bromo-3-iodo-1H-pyrrolo[3,2-b]pyridine

[0225] Compound 21-1 : 5-bromo-3-iodo-1 H-pyrrolo[3,2-b]pyridine (170 mg, 35% yield) was obtained as a white solid.1H NMR (400 MHz, DMSO-d6) δ 8.48 (s, 1H), 7.82 (s, 1H), 7.62 (s, 1H).

[0226] LC-MS: [ESI] [M+H] = 323.0 +

[0227] Second step: synthesis of compound 21-2: 5-bromo-3-iodo-1 -p-tolylsulfonyl- 1 H-pyrrolo[3,2-b]pyridine

[0228] Compound 21-1 : 5-bromo-3-iodo-1 H-pyrrolo[3,2-b]pyridine (170 mg, 0.53 mmol), DMAP (1.0 mg, 0.01 mmol), DIPEA (157 mg, 1.21 mmol) were dissolved in dichloromethane (3 mL) and p-tolylsulfonyl chloride (120 mg, 0.63 mmol) was added. The reaction was stirred at room temperature for 2 hours until the reaction was complete (TLC test, mobile phase, ethyl acetate / petroleum ether, 20%). The reaction was added with water (10 mL) and extracted with ethyl acetate (20 mL) three times. The organic phases were combined, washed with brine (10 mL) once, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated and the residue was purified by column chromatography on silica gel (mobile phase, ethyl acetate / petroleum ether, 0-20%) to obtain compound 21-2: 5-bromo-3-iodo-1 -p-tolylsulfonyl- 1 H-pyrrolo[3,2-b]pyridine (230 mg, 92% yield) as a white solid.

[0229] LC-MS: [ESI] [M+H] = 476.9. +

[0230] Third step: synthesis of compound 21-3: 5-bromo-1 -p-tolylsulfonyl-3-(3,3,3- trifluoroprop-1 -en-2-yl)-1 H-pyrrolo[3,2-b]pyridine

[0231] ​​Compound 21-2: 5-bromo-3-iodo-l-p-tolylsulfonyl-lH-pyrrolo[3,2-b]pyridine (50 mg, 0.11 mmol) was dissolved in a mixture of dioxane / water (10 mL / 2 mL) with 4,4,6-trimethyl-2-(3,3,3-trifluoroprop-l-en-2-yl)-l,3,2-dioxaborolane (28 mg, 0.13 mmol) and Pd(dppf)Cl2(77 mg, 0.11 mmol) and potassium carbonate (44 mg, 0.32 mmol) was added. The reaction was purged with nitrogen and heated to 110 °C and stirred for 12 hours until the reaction was complete. The reaction was added with water (10 mL) and extracted with ethyl acetate (10 mL) three times. The organic phase was combined and washed with brine (5 mL) once, dried over anhydrous sodium sulfate, filtered. The filtrate was concentrated and the residue was purified using silica gel column chromatography (mobile phase: ethyl acetate / petroleum ether, 10%) to give compound 21-3: 5-bromo-l-p-tolylsulfonyl-3-(3,3,3-trifluoroprop-l-en-2-yl)-lH-pyrrolo[3,2-b]pyridine (30 mg, yield 64%) as a white solid.

[0232] LC-MS: [ESI] [M+H] + = 445.0.

[0233] Fourth step: synthesis of compound 21-4: 5-(4-(benzyloxy)-2,6-dimethylbenzyl)-l-p-tolylsulfonyl-3-(3,3,3-trifluoroprop-l-en-2-yl)-lH-pyrrolo[3,2-b]pyridine

[0234] Compound 21-3: 5-bromo-l-p-tolylsulfonyl-3-(3,3,3-trifluoroprop-l-en-2-yl)-lH- pyrrolo[3,2-b]pyridine (4.10 g, 9.21 mmol), compound 1-5: 2-(4-(benzyloxy)-2,6- dimethylbenzyl)-boronic acid pinacol ester (5.22 g, 12.90 mmol), dichlorobis(tris- o-tolylphosphine)palladium(II) (1.09 g, 1.38 mmol) and potassium phosphate (5.86 g, 27.63 mmol) were dissolved in a mixture of dioxane and water (50 mL, 5 / 1). The reaction was purged with nitrogen and heated to 100 °C and stirred for 12 hours until the reaction was complete. The reaction was added to water (100 mL) and extracted with ethyl acetate (100 mL) three times. The organic phase was combined and washed with brine (100 mL), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated and the residue was purified by silica gel column chromatography (mobile phase, ethyl acetate / petroleum ether, 0-10%) to give compound 21-4: 5-(4-(benzyloxy)-2,6-dimethylbenzyl)-l-p-tolylsulfonyl-3-(3,3,3- trifluoroprop-l-en-2-yl)-lH-pyrrolo[3,2-b]pyridine (1.00 g, yield 18%) as a yellow solid.

[0235] LC-MS: [ESI] [M+H] = 591.0. +

[0236] Fifth step: synthesis of compound 21-5: 5-(4-(benzyloxy)-2,6-dimethylbenzyl)-l-p- tolylsulfonyl-3-(l,l,l-trifluoroprop-2-yl)-lH-pyrrolo[3,2-b]pyridine

[0237] Compound 21-4: 5-(4-(benzyloxy)-2,6-dimethylbenzyl)-l-p-tolylsulfonyl-3-(3,3,3- trifluoroprop-l-en-2-yl)-lH-pyrrolo[3,2-b]pyridine (2.00 g, 3.39 mmol) was dissolved in methanol (20 mL) and purged with nitrogen. Palladium on carbon (200 mg, 10% content) was added and purged with hydrogen three times. The reaction was stirred for 12 hours under hydrogen atmosphere until the reaction was complete. The reaction was filtered with celite and the filtrate was concentrated to dryness to give compound 21-5: 5-(4-(benzyloxy)-2,6-dimethylbenzyl)-l-p-tolylsulfonyl-3-(l,l,l- trifluoroprop-2-yl)-lH-pyrrolo[3,2-b]pyridine (1.80 g, crude) which was used directly in the next step.

[0238] LC-MS: [ESI] [M+H] = 593.0. +

[0239] ​​Step 6: Synthesis of compound 21-6: 3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenol

[0240] Compound 21-5: 5-(4-(benzyloxy)-2,6-dimethylbenzyl)-1-p-tolylsulfonyl-3-(1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridine (1.80 g, crude) from the previous step was dissolved in dichloromethane (10 mL) and cooled to 0 °C. To the reaction was added boron tribromide (3.27 mL, 33.9 mmol) dropwise and the reaction was allowed to warm to 0 °C and stirring was continued for 3 hours until the reaction was complete. To the reaction was added water (5 mL) and stirring was continued for 1 hour and additional water (20 mL) was added and extracted with ethyl acetate (10 mL) three times. The organic phases were combined, dried over anhydrous sodium sulfate and concentrated. The residue was chromatographed on a silica gel column (mobile phase, ethyl acetate / petroleum ether, 0-50%) to give 21-6: 3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1-trifluoropropyl-2-yl)-1H- pyrrolo[3,2-b]pyridin-5-yl)methyl)phenol as a white solid (800 mg, 47% yield).

[0241] LC-MS: [ESI] [M+H] + = 503.0

[0242] Step 7: Synthesis of compound 21-7: 3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenol triflate

[0243] Compound 21-6: 3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1-trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenol (700 mg, 1.39 mmol) and pyridine (0.30 mL, 3.48 mmol) were dissolved in dichloromethane (10 mL), and the reaction system was cooled to 0 °C under nitrogen protection. Trifluoromethylsulfonic anhydride (786.00 mg, 2.79 mmol) was slowly added dropwise into the reaction solution, and stirring was continued at 0 °C for 1 hour until the reaction was complete. Water (10 mL) was added to the reaction solution and extracted with dichloromethane (10 mL). The organic phase was separated and washed with brine (30 mL) three times, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated, and the residue was purified by silica gel column chromatography (mobile phase, ethyl acetate / petroleum ether, 0-10%) to obtain compound 21-7: 3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1-trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenol triflate (800 mg, yield 97%) as a colorless oil.

[0244] LC-MS: [ESI] [M+H] + = 635.0

[0245] Activity data of amorphous compound 1 (compound 48-B):

[0246] Biological activity test method:

[0247] (1) Cell culture

[0248] Human hepatoma cell line HepG2 cells were cultured in MEM containing 10% bovine serum albumin (BSA). Primary hepatocytes were seeded on a 24-well plate coated with hepatocyte culture medium from Celsis for culture.

[0249] (2) RNA extraction, reverse transcription and real-time quantitative PCR (qRT-PCR) analysis

[0250] Total RNA was extracted from cell lysates using an RNA extraction kit, and the integrity of the total RNA was detected by agarose gel electrophoresis (EB staining). 2 μg of total RNA was used to synthesize cDNA by reverse transcription kit using random primers, and then real-time quantitative PCR reaction was performed on an Eppendorf PCR instrument using PCR premix. The reaction program was as follows: 50 °C, 2 min; 95 °C, 10 min; 95 °C, 15 s; 60 °C, 60 s for 40 cycles, two replicates were analyzed in parallel for each cDNA sample, GAPDH was used as an internal reference gene to correct the expression of target gene mRNA, and the relative expression level of mRNA was calculated by 2-ΔΔCt method. The primer sequences used in human gene expression test are shown in the following table:

[0251] (3) Transient transfection of LDLR reporter vector

[0252] HepG2 cells were seeded at a density of 4 x 10 4 cells per well in 96-well plates and co-transfected with luciferase- tagged LDLR promoter vector and THR-beta vector. One day post-transfection, the media was changed to MEM containing 0.5% FBS and compounds were added for 24 h. Cells were lysed with 100 μL reporter lysis buffer per well and luciferase activity was measured using a luciferase assay kit. Triplicate samples were analyzed for each transfection condition and each promoter construct was tested at least four independent times.

[0253] (4) Co-transient transfection of luciferase-tagged TRE-Luc gene vector with THR-beta or THR-alpha vector

[0254] Materials, reagents, equipment and consumables

[0255] HEK293T cells were seeded at a density of 6 x 10 6 cells per well in 100 mM dishes and co-transfected with luciferase-tagged TRE-Luc promoter vector and THR-beta or THR-alpha vector (THR-beta: 6.25 μg + pGL4.35: 2.5 μg; THR-alpha: 6.25 μg + pGL4.35: 2.5 μg). 50 nL compound dilutions were transferred to a 384-well assay plate using an Echo 655. Six hours post-transfection, cells were trypsinized and re-seeded into 384-well plates at a density of 15,000 cells per well in DMEM containing 10% charcoal stripped FBS. Twenty-four hours later, 25 μL britelite plus Luciferase Assay Reagent was added to each well of the 384-well plate and luminescence values were recorded on an Envision plate reader. The RLU signal value (LUM 化合物 ) was calculated for each well.

[0256] %Activity was calculated as follows: %Activity = (Signal 化合物 -Signal Ave_VC ) / (Signal Ave_PC -Signal Ave_VC ) x 100. Signal ave_pc: average signal of positive controls across the plate; Signal ave_nc: average signal of negative controls across the plate.

[0257] EC50values were calculated by fitting the % activity values of compound concentrations to a non-linear regression (dose response - variable slope) using Graphpad 8.0 50 .

[0258] (5) Effect of test compounds on TRa and TRP binding activity in TR-FRET assay

[0259] 1. Materials and Instruments

[0260] 2. Experimental Procedure

[0261] Compound 48-A, 48-B and MGL-3196 were prepared in DMSO starting at 1 mM, 3-fold dilution, 9 doses, 1 zero point.

[0262] Positive compound T3 was prepared in DMSO starting at 10 mM, 3-fold dilution, 10 doses.

[0263] Prepare 100x positive control (10 mM T3) and 100x negative control (100% DMSO).

[0264] Compound screening: Dilute T3 and test compounds in DMSO in gradient, ready for use.

[0265] Dilute 100x compounds prepared in step a with 1x reaction buffer to 4x.

[0266] Take 5 pL of 4x compounds prepared in step b to 384-well plate.

[0267] Prepare 4x TRa or 4x TRP, 4x RxRa working solution with 1x reaction buffer.

[0268] Take 5 pL of step d solution to 384-well plate.

[0269] Prepare mixture containing 2x Biotin-SRC2-2, 2x Europium anti-GST and 2x Streptavidin-d2 with 1x reaction buffer.

[0270] Take 10 pL of mixture prepared in step f to 384-well plate.

[0271] Centrifuge experimental plate at 1000 rpm for 1 min.

[0272] Incubate at room temperature for 4 h in the dark.

[0273] Read values at wavelengths 665 nm and 615 nm using Envision.

[0274] Data analysis

[0275] Activity rate calculation

[0276] Ratio: 665 nm / 615 nm

[0277] (Ratio) - Positive Control: Average of all positive control wells ratio across the plate.

[0278] (Ratio) - Negative Control: Average of all negative control wells ratio across the plate.

[0279] EC50calculation 50 and fitting of compound dose-response curves

[0280] The EC50of the compounds was obtained using the following non-linear fitting equation 50 (Agony Concentration 50). Y = Bottom + (Top - Bottom) / (1 + 10^((LogEC 50 -x)*HillSlope))

[0281] X: Compound concentration log value; Y: Compound activity rate.

[0282] (1) Activity experiment 1 of racemic amorphous compound 1 (compound 48):

[0283] The purpose of this analysis was to measure the degree of THR-β activation by the levels of ANGPTL4 and ABCD2 mRNA expression in Huh7 cells, to evaluate the effect of compound 48 and MGL-3196 on the thyroid hormone nuclear receptor pathway in Huh7 cells, by measuring the EC 50 values.

[0284] Huh7 cells seeded in 96-well plates in 10% charcoal stripped FBS DMEM were treated with compound 48, MGL-3196 at the indicated doses (10000, 2500, 625, 156.25, 39.06, 9.76, 2.44 nM, 0.3% DMSO as a blank control) for 24 hours, RNA was extracted using TaqMan TM Fast Advanced Cells-to-CT TM kit and real-time quantitative nucleic acid amplification (qPCR) was performed for ANGPTL4 and ABCD2 mRNA expression. Table 1 represents the results of the 2 replicates (average) of ANGPTL4 and ABCD2 expression normalized to the housekeeping gene ACTB (b-actin) mRNA levels, where the relative expression of ANGPTL4 and ABCD2 mRNA in MGL-3196 (positive control) treated cells was defined as 1. The results demonstrate that compound 48 has an EC50 Compound 48-B was a potent increase in ABCD2 mRNA levels at 46.63 nM (8 times more potent than MGL-3196 activity) with an EC 50 Compound 48-B was a potent increase in ANGPTL4 mRNA levels at 355.2 nM (3.45 times more potent than MGL-3196 activity).

[0285] Table 1

[0286] (2) Activity Experiment 2 of Compound 48-A and Amorphous Compound 1 (Compound 48-B):

[0287] Effect of test compounds on THR-β and THR-α binding activity in TR-FRET in vitro experiment

[0288] The TR-FRET assay method is an in vitro analysis of the agonistic activity of a compound on THR-β and THR-α, which is performed using a time-resolved fluorescence resonance energy transfer co-activation state recruitment experiment. The purpose of this experiment is to evaluate the in vitro activity of a compound of the present application to increase the recruitment of a fluorescence resonance energy transfer co-activation state by activating THR-β and THR-α, in order to calculate the THR-β selectivity of the test compound.

[0289] Table 2:

[0290] This experiment tested the effect of a compound on TRα and TRβ binding activity at different concentrations (Table 2). The experimental results showed that Compound 48-B was much higher in TRβ binding activity (EC 50 = 6.0 nM) than in TRα binding activity (EC 50 = 632.0 nM), and the formula for calculating β selectivity = THR-α EC 50 / THR-β EC 50 . Therefore, the THR-β selectivity of Compound 48-B was 105.3 times, which was higher than that of its optical isomer 48-A (31 times) and the positive control drug MGL-3196 (21.8 times).

[0291] (3) Activity Experiment 3 of Racemic Amorphous Compound 1 (Compound 48), Compound 48-A, and Amorphous Compound 1 (Compound 48-B):

[0292] THR-β is expressed in other tissues in addition to the liver, including the brain, thyroid, muscle, and adipose tissue. Activation of THR-β in tissues other than the liver can cause unwanted side effects and possible toxicity. Therefore, it is necessary to develop a liver-targeting THR-β agonist for better safety.

[0293] To screen liver-targeted THR-β selective agonists, the present application provides a co-transfection assay for TRE-Luc reporter assay in the presence of plasmids expressing THR-β and human organic anion transporting polypeptide (SLCO1B1) or control plasmids (pCI-Neo) expressing no human protein. The SLC01B1 transporter is only expressed in human liver tissue, so its substrate has strong liver targeting. Table 3 shows that the effect of T3 activating THR-β is not affected by the expression of SLC01B1, while the expression of SLC01B1 enhances the activity of MGL-3196. This is consistent with a new report that MGL-3196 is actively transported into liver cells by SLOC1B1 and is a liver-targeted THR-β agonist (Int. J. Mol. Sci. 2022, 23, 13714).

[0294] This activity test screens the new compounds disclosed in the present application, such as compounds 48, 48-A, and 48-B, which are identified as liver-targeted THR-β agonists, and have higher activity and stronger liver targeting than MGL-3196 (MGL-3196 SLC01B1 / control group value = 3.4 (Experiment No. 1), MGL-3196 SLC01B1 / control group value = 2.8 (Experiment No. 2). The EC 50 50 values of T3 are not affected by the expression of the transporter SLC01B1, and the effect of MGL-3196 on the activation of THR-β is enhanced by about 3 times in the presence of the transporter SLC01B1, with an EC 50 50 value of 694.4 nM. Compared with T3, the strong activity of the compounds 48 and their resolved chiral isomers 48-A and 48-B of the present application on the activation of THR-β is further enhanced by 8-10 times in the presence of the transporter SLC01B1, and 48-B reaches an EC 50 50 value of less than 50 nM. The effect of the compound 48-B of the present application on the activation of THR-β is enhanced by about 25 times in the presence of the transporter SLC01B1, with an EC 50 50 value of 13 nM (Experiment No. 4).

[0295] Table 3:

[0296] (4) Activity test 4 of the racemate of amorphous compound 1 (compound 48)

[0297] C57BL / 6 mice were fed a high cholesterol diet for three weeks and orally gavaged with Compound 48 at 0.5 mg / kg, 1 mg / kg and 5 mg / kg daily for one week, while the control group received vehicle only. Serum samples were collected at baseline and after 7 days for TC and LDL-C measurements. Liver, heart, brain tissue samples and plasma samples were collected 24 hours after the last treatment for Compound measurement. Total RNA was also extracted from liver and heart tissues for qRT-PCR analysis. The experimental results (as shown in Figure 15) showed that Compound 48 dose-dependently reduced serum TC and LDL-C, where Veh represents the vehicle group, Day 0 and Day 7 represent the baseline and 7-day measurements, respectively.

[0298] The measurement results of Compound 48 concentration in tissues (as shown in Figure 16) showed that Compound 48 was not detected in the brain, and the level detected in the blood and heart was very low, but it was highly enriched in liver tissue. At a dose of 5 mg / kg, the liver tissue concentration of Compound 48 was 62.5 times that of the heart and 61 times that of the plasma. Both in vivo test Example 15 and in vitro test Example 13 prove that Compound 48 is a liver-targeted THR-β selective agonist.

[0299] The liver mRNA level analysis of THR-β target genes showed that Compound 48 increased Me1 mRNA levels in a dose-dependent manner (as shown in Figure 17A), in contrast, the mRNA levels of Me1 in heart tissue were not changed (as shown in Figure 17B), which is consistent with the tissue distribution results showing that the content of the compound in the heart tissue is very low, which proves that the liver-targeted THR-β selective agonist has a very low concentration in non-target organs, and has better safety. In this experiment, it can be observed that Compound 48 treatment at all doses did not change plasma TSH levels, glucose levels, or liver enzyme ALT / AST levels, indicating that Compound 48 of the present application has good safety in vivo.

[0300] This example shows that the liver-targeted THR-β selective agonist Compound 48 shows strong efficacy in reducing cholesterol, and has ideal tissue distribution and excellent safety.

[0301] (5) Activity test 5 of amorphous Compound 1 (Compound 48-B)

[0302] The liver-targeted THR-β selective agonist Compound 48-B has shown strong anti-NASH activity and high liver targeting at a dose less than 20 times lower than the positive drug MGL-3196 in the NASH therapeutic model of HFD+CCL4 mice.

[0303] The purpose of this experiment is to study the pharmacodynamic effect of compound 48-B in alleviating the clinical symptoms and pathological changes of NASH in a NASH mouse model induced by high-fat diet (HFD) plus carbon tetrachloride (CCl4).

[0304] In this experiment, DIO mice induced by high-fat diet were intraperitoneally injected with 0.5 mL / kg 25% CCl4 (2 times per week, a total of 8 times) to induce non-alcoholic steatohepatitis (NASH). All mice were given intragastric administration once a day for 28 consecutive days.

[0305] The grouping of experimental animals is as follows Table 4:

[0306] Table 4:

[0307] The mice in each group were administered according to the following Table 5:

[0308] Table 5:

[0309] The experimental results are shown in Figure 18. Compared with normal mice, the liver TG and TC levels of the model control group of mice were significantly increased. Compared with the model group, compound 48-B at a low dose of 0.5 mg / kg has significantly reduced the liver TG (A), TC (B) and NASH score (C) of mice, and reached the same efficacy level as the 10 mg / kg dose of MGL-3196.

[0310] The livers and plasma of mice were collected 24 hours after the last treatment for measurement of compound 48-B. At the end of the experiment, the compound 48-B concentration measurement results are shown in Figure 19.

[0311] Compound 48-B (0.5 mg / kg) has a similar biological effect as MGL-3196 (10 mg / kg), and the liver C min only 3% of MGL-3196, and the blood concentration of compound 48-B is 0.2% of the blood concentration of MGL-3196.

[0312] This activity experiment, together with Activity Experiment 4, demonstrates that the liver-blood ratio of compound 48-B is greater than 50 times (much higher than the liver-blood ratio of positive control MGL-3196 which is less than 5 times), which is a highly liver-targeted and potent THR-β selective agonist in the field of treating NASH, and is expected to have very good safety in clinical practice.

[0313] Preparation method of Example 1 crystal form A

[0314] Preparation of Form A: Amorphous Compound 1 (1.0 g) was dissolved in DMAc (10 mL) and filtered. When water (10 mL) was added dropwise at room temperature, a large amount of solid precipitated. The precipitate was filtered under reduced pressure and dried at 220 °C for 30 min. The product was a white solid (640 mg). The XRPD spectrum of Form A is shown in Figure 1.

[0315] The DSC spectrum of Form A is shown in Figure 2. The endothermic peak is at 307.7 °C. The TGA spectrum of Form A is shown in Figure 3. The 0.1% weight loss at 120.0 °C is due to solvent residue.

[0316] Form A remained stable in the pressure test. In terms of hygroscopicity, Form A absorbed about 0.44% moisture at 80% RH for 24 hours, which is slightly hygroscopic. In terms of chemical stability, two packaging methods were tested under high temperature and high humidity conditions. The key items under various conditions showed good stability.

[0317] Characterization data:

[0318] The XRPD spectrum of Form A is shown in Figure 1. The data are shown in Table 6 below.

[0319] Table 6:

[0320] Pressure test of Form A of Example 2

[0321] Pressure test of Form A: A small amount of Compound 1 was wrapped in weighing paper and placed in the following conditions for 3 min. The XRPD was then measured.

[0322] Table 7:

[0323] The results show that Form A remains stable in the pressure test, although the crystallinity decreases.

[0324] Evaluation of hygroscopicity of Form A of Example 3

[0325] According to the guidelines for drug hygroscopicity in the pharmacopoeia method, an appropriate amount of Form A was placed in a dry stoppered glass weighing bottle (previously placed in a 25 °C constant temperature dryer) and left open in a constant temperature and humidity chamber with a cap. The bottle was placed in a constant temperature and humidity chamber at 25 °C and 80% RH ± 2% for 24 hours, and the weight was accurately measured. The XRPD spectra before and after hygroscopicity are shown in Figure 4.

[0326] Table 8:

[0327] Stability test of Form A of Example 4

[0328] Table 9:

[0329] Stability test showed that Form A was very stable in high temperature or high humidity conditions, whether open or with outer packaging, the key items such as test purity, maximum single impurity and crystal form were very stable.

[0330] Example 5 Preparation method of other Form A

[0331] Compound 1 (400 mg, Form D) was weighed into a 5 mL vial, DMF (2.5 mL) was added, stirred at room temperature for 2 h, and filtered to obtain a clear solution. Water (0.2 mL) was slowly added to the clear solution, and a large amount of solid was precipitated. The obtained solid was filtered and vacuum dried at 50 °C for 18 h to obtain Form A of Compound 1 (270 mg).

[0332] Example 6 Preparation method of Form B

[0333] Preparation of Form B: Compound 1 (Form A, 400 mg) was concentrated to dryness by rotary evaporation to obtain a solid, which was transferred to an 8 mL vial. Tetrahydrofuran (2.4 mL) was added at room temperature, and the sample was stirred magnetically for 6 h. The sample was sampled and measured by XRPD, as shown in Figure 5, which showed Form B. The DSC spectrum of Form B (Figure 6) showed an exothermic peak at 224.6 °C and an endothermic peak at 309.4 °C; the TGA spectrum (Figure 7) showed a weight loss of 0.28% at 120.0 °C.

[0334] As shown in the XRPD spectrum of Figure 5, it was Form B, and the data are as follows in Table 10:

[0335] Table 10:

[0336] Example 7 Thermal stability test of Form B solid

[0337] About 10 mg of Form B was heated to 220 °C at a rate of 10 °C / min by TGA (Figure 71), and the remaining sample was measured by XRPD after the sample was cooled to room temperature. It was found that Form B was converted to Form A, and the Form A was placed in a fume hood for 18 h without any sign of crystal conversion.

[0338] The test showed that Form B would be converted to the thermodynamically more stable Form A in the thermal stability test of solid. Form B is a metastable crystal form.

[0339] Example 8 Preparation method of Form C

[0340] About 800 μL of a clear solution of Form A of raw drug in acetone / MTBE (1:3, v:v) at a concentration of about 15 mg / mL was placed in a fume hood and slowly evaporated for 18 h to precipitate a solid, which was Form C.

[0341] The DSC pattern of Form C (Figure 9) shows an endothermic peak at 72.5 °C; an exothermic peak at 209.8 °C; and an endothermic peak at 309.5 °C. Form C is shown to be a solvate, which can be converted to Form A upon heating to about 309 °C.

[0342] The XRPD pattern of Example 9 (Figure 10) shows Form D, and the data is shown in Table 12.

[0343] Table 12:

[0344] Preparation of Form D

[0345] About 100 mg of Form D of Compound 1 was heated to 220 °C in a muffle furnace at 115 °C for 30 min to obtain Form E, which has an XRPD pattern as shown in Figure 14. The DSC pattern (Figure 13) shows an exothermic peak at 254.3 °C and an endothermic peak at 311.2 °C. The TGA pattern (Figure 15) shows a weight loss of 0.35% at 105 °C, which is due to the solvent residue.

[0346] Phase transition of Form D:

[0347] Form D can be converted to Form E upon heating to 220 °C in a muffle furnace, and to Form A upon heating to 290 °C.

[0348] The DSC pattern of Form D (Figure 11) shows an endothermic peak at 25.6 °C, an endothermic peak at 90.0 °C; an exothermic peak at 184.2 °C, which shows a possible phase transition to Form E; and an endothermic peak at 311.6 °C, which shows a phase transition to Form A. The TGA pattern (Figure 12) shows a weight loss of 1.42% at 120.0 °C.

[0349] The XRPD pattern of Example 9 (Figure 10) shows Form D, and the data is shown in Table 12.

[0350] Table 12:

[0351] Preparation of Form E

[0352] About 100 mg of Form D of Compound 1 was heated to 220 °C in a muffle furnace at 115 °C for 30 min to obtain Form E, which has an XRPD pattern as shown in Figure 14. The DSC pattern (Figure 13) shows an exothermic peak at 254.3 °C and an endothermic peak at 311.2 °C. The TGA pattern (Figure 15) shows a weight loss of 0.35% at 105 °C, which is due to the solvent residue.

[0353] The XRPD pattern of Example 9 (Figure 10) shows Form D, and the data is shown in Table 12.

[0354] Table 13:

[0355] Study on the crystal form conversion of Example 11 crystal form E to crystal form D

[0356] The crystal form E was continuously heated to 290°C in a muffle furnace, and it was found that it was converted to crystal form A.

[0357] The crystal form D was directly heated to 290°C in a muffle furnace, and it was found that it was also converted to crystal form A. Therefore, crystal form E is a relatively unstable crystal form.

[0358] Example 12 Comparison test of solubility of various crystal forms in different pH simulated gastrointestinal fluids

[0359] Preparation method of different pH solutions:

[0360] Preparation method of pH 1.2 hydrochloric acid solution: take 7.65 mL of hydrochloric acid, dilute with water to 1000 mL, and shake well.

[0361] Preparation method of pH 4.5 acetate buffer solution: 2.0 mol / L acetic acid solution: take 120.0 g (114 mL) of glacial acetic acid and dilute with water to 1000 mL to obtain the acetic acid solution. Take 2.99 g of sodium acetate, add 14.0 mL of the above 2 mol / L acetic acid solution, dissolve and dilute with water to 1000 mL, and shake well.

[0362] Preparation method of pH 6.8 phosphate buffer solution: 0.2 mol / L potassium dihydrogen phosphate solution: take 27.22 g of potassium dihydrogen phosphate, dissolve and dilute with water to 1000 mL. 0.2 mol / L sodium hydroxide solution: take 8.00 g of sodium hydroxide, dissolve and dilute with water to 1000 mL. Mix 250 mL of 0.2 mol / L potassium dihydrogen phosphate solution with 112.0 mL of 0.2 mol / L sodium hydroxide solution, and then dilute with water to 1000 mL, and shake well.

[0363] Preparation method of pH 7.4 phosphate buffer solution: mix 250 mL of 0.2 mol / L potassium dihydrogen phosphate solution with 195.5 mL of 0.2 mol / L sodium hydroxide solution, and then dilute with water to 1000 mL, and shake well.

[0364] Thermodynamic solubility test method under different pH conditions:

[0365] Take an appropriate amount of each test sample and place it in a glass bottle of appropriate size. Add a certain amount of buffer solution of different pH values to prepare a supersaturated solution. Place the glass bottle in a constant temperature shaker, shake at 25°C for 24 hours, and observe the phenomenon. Quantitatively dilute the supernatant, detect the concentration of the supernatant by high performance liquid chromatography external standard method, and calculate the thermodynamic solubility of the test sample under the corresponding pH conditions at a constant temperature.

[0366] Table 14:

[0367] Compound 1 (Form A) showed superior tissue distribution profile compared to positive control MGL-3196 in cynomolgus monkeys

[0368] Objective of the experiment: To compare the pharmacokinetic and liver targeting profiles of Compound 1 (Form A) and positive control MGL-3196 in cynomolgus monkeys

[0369] Instrument list:

[0370] Experimental reagents

[0371] Animal experiment design and experimental operation

[0372] Animal selection: From the cynomolgus monkey group, through liver and kidney function detection, 9 qualified animals were selected for screening, and finally 6 healthy animals were selected for enrollment.

[0373] Adaptation period: 7 days.

[0374] Experimental grouping and dosing

[0375] Grouping: A total of 6 enrolled animals will be grouped according to the test substance (Group 1: Compound 1 (Form A), Group 2: MGL-3196). And divided into two batches, the first batch and the second batch of experiments are separated by 7 days.

[0376] Dosing: In the first batch of each group, three male cynomolgus monkeys with similar body weights were orally gavaged with 5 mg / kg of Compound, and plasma samples were collected at 0-24 hours; In the second batch of cynomolgus monkeys in the same group, 5 mg / kg of Compound was administered orally for the second time, and after the plasma sample was collected at 4h, the animals were subjected to liver biopsy, 2 needles per animal, about 20 mg sample, and the sample was frozen in liquid nitrogen and stored at -80°C.

[0377] Analysis: The collected plasma and liver tissue samples were analyzed by LC-MS / MS method, the concentrations of Compound 1 (Form A) and MGL-3196 in each group of plasma were determined, the pharmacokinetic parameters were calculated, and the average liver tissue / plasma drug concentration ratio was calculated.

[0378] Experimental results

[0379] The results (Table 16) show that the Tmax of Compound 1 (Form A) and MGL-3196 in cynomolgus monkey plasma were both 4 h after oral gavage of 5 mg / kg dose of Compound 1 (Form A) and MGL-3196, respectively, the T1 / 2 were 1.99-2.52 h and 1.54-2.44 h, respectively, the average Cmax were 68.4 ± 38.6 ng / mL and 135 ± 64.5 ng / mL, respectively, and the plasma exposure AUCo-t were 386 ± 187 h*ng / mL and 657 ± 185 h*ng / mL, respectively.

[0380] The average liver tissue / plasma drug concentration ratio of 5 mg / kg Compound 1 (Form A) oral gavage group was 54.9 ± 33.7 at 4 h, and the average liver tissue / plasma drug concentration ratio of 5 mg / kg MGL-3196 oral gavage group was 12.0 ± 4.44 at 4 h. The liver tissue / plasma drug concentration ratio of 5 mg / kg Compound 1 (Form A) oral gavage group was higher than that of 5 mg / kg MGL-3196 oral gavage group, about 4.58 times of MGL-3196 at 4 h.

[0381] Table 15: Pharmacokinetic parameters of Compound 1 (Form A) and MGL-3196 in cynomolgus monkey plasma after single oral gavage of 5 mg / kg Compound 1 (Form A) and MGL-3196, respectively

[0382] Example 13 Preparation of amorphous Compound 1

[0383] First step, synthesis of Compound 3: tert-butyl (3,5-dimethyl-4-((4,4,5,5-tetramethyl-1,3,2-dioxaboran-2-yl)methyl)phenyl)carbamate

[0384] Compound 3: tert-butyl (3,5-dimethyl-4-((4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2- yl)methyl)phenyl)carbamate (51.2 g, 85% yield) was obtained as a white solid.1H NMR (400 MHz, DMSO-d6) δ 9.02 (br, 1H), 7.08 (s, 2H), 2.17 (s, 6H), 2.10 (s, 2H), 1.51 (s, 9H), 1.19 (s, 12H) ppm.

[0385] LC-MS: [ESI] [M+H] + = 362.3.

[0386] 1 1H NMR (400 MHz, DMSO-d6) δ 9.02 (br, 1H), 7.08 (s, 2H), 2.17 (s, 6H), 2.10 (s, 2H), 1.51 (s, 9H), 1.19 (s, 12H) ppm.

[0387] Second Step Synthesis of Compound 4: tert-butyl (3,5-dimethyl-4-((l-p-toluenesulfonyl-3-(3,3,3-trifluoroprop-l-en-2-yl)-lH-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)carbamate

[0388] A mixture of 5-bromo-l-(p-tolylsulfonyl)-3-(3,3,3-trifluoropropenyl-l-en-2-yl)-lH- pyrrolo[3,2-b]pyridine (20.0 g, 44.9 mmol), compound 3 (12.9 g, 35.7 mmol), Pd(dppf)Cl2(3.26 g, 4.49 mmol) and potassium phosphate (28.4 g, 134.7 mmol) in dioxane (200 mL) and water (100 mL) was purged with nitrogen three times, heated to reflux and stirred for 72 hours until the reaction was completed. The reaction was cooled to room temperature, ethyl acetate (200 mL) was added and washed with water (200 mL). The aqueous phase was extracted with ethyl acetate (200 mL) once and the organic phases were combined and washed with brine (100 mL) once. The organic phase was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated and the residue was purified by column chromatography on silica gel (mobile phase, ethyl acetate / petroleum ether, 0-80%) to give compound 4 as a white solid (21.5 g, 80% yield).

[0389] LC-MS: [ESI] [M+H] + = 600.7.

[0390] 1 H NMR (400 MHz, DMSO-d6) δ 9.12 (br, 1H), 8.28 (d, J = 8.0 Hz, 1H), 7.95 (br, J = 8.0 Hz, 2H), 7.89 (s, 1H), 7.40 (d, J = 8.0 Hz, 2H), 7.20 (s, 1H), 7.10-7.13 (m, 3H), 6.20 (s, 1H), 4.16 (s, 2H), 2.31 (s, 3H), 2.07 (s, 6H), 1.45 (s, 9H) ppm.

[0391] Third Step Synthesis of compound 5: (S)-(3,5-dimethyl-4-((l-p-tolylsulfonyl-3-(l,l,l- trifluoropropyl-2-yl)-lH-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)carbamic acid tert-butyl ester

[0392] Compound 4 (20.0 g, 33.4 mmol) was dissolved in methanol (500 mL), and methanol (1000 mL) was added to a clean and dry reaction flask. The flask was purged with nitrogen three times, and then a catalyst [Ru(p-cymene)Cl2]2(2.0 g, 3.34 mmol) and a ligand R-BINAP (4.3 g, 6.68 mmol) were added. The flask was purged with nitrogen three times, and then purged with hydrogen three times. The reaction was stirred at 40-45 °C under a hydrogen atmosphere for 4 hours. The reaction solution was filtered with celite, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel column chromatography (mobile phase, ethyl acetate / petroleum ether, 0-80%) to obtain compound 5 (29.4 g, yield 88%) as a white solid.

[0393] LC-MS: [ESI] [M+H] + = 602.7

[0394] 1 H NMR (400 MHz, DMSO-d6) δ 9.13 (br, 1H), 8.12-8.15 (m, 2H), 7.89 (d, J = 8.0 Hz, 2H), 7.39 (d, J = 8.0 Hz, 2H), 7.13 (s, 2H), 7.92 (d, J = 8.0 Hz, 1H), 4.10-4.13 (m, 3H), 2.32 (s, 3H), 2.19 (s, 6H), 1.53 (d, J = 7.2 Hz, 3H), 1.46 (s, 6H) ppm.

[0395] Fourth Step Synthesis of Compound 6: (S)-3,5-dimethyl-4-((1-p-tolylsulfonyl-3-(1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)aniline

[0396] Compound 5 (29.0 g, 48.3 mmol) was dissolved in dioxane (300 mL), and a hydrogen chloride dioxane solution (4 M, 24.1 mL, 96.5 mmol) was added dropwise. The reaction was stirred at room temperature for 2 hours until the reaction was complete. The reaction solution was concentrated to dryness, and the residue was added to water (200 mL) and adjusted to pH = 7 with sodium hydroxide (4 M). The precipitated solid was filtered, and the filter cake was collected and dried to obtain compound 6 (15.9 g, yield 95%) as a white solid.

[0397] LC-MS: [ESI] [M+H] + = 502.6

[0398] 1H NMR (400 MHz, DMSO-d6) δ 8.12 - 8.17 (m, 2H), 7.89 (d, J = 8.0 Hz, 2H), 7.40 (d, J = 8.0 Hz, 2H), 6.89 (d, J = 8.0 Hz, 1H), 6.26 (s, 2H), 4.76 (s, 2H), 4.00 - 4.04 (m, 3H), 2.32 (s, 3H), 2.09 (s, 6H), 1.54 (d, J = 8.0 Hz, 3H) ppm.

[0399] Step 5 Synthesis of compound 7: (S)-3,5-dimethyl-4-((3-(1,1,1-trifluoropropyl-2-yl)-1H- pyrrolo[3,2-b]pyridin-5-yl)methyl)aniline

[0400] Compound 6 (15.0 g, 29.9 mmol) was dissolved in methanol (100 mL), potassium carbonate (19.1 g, 138.3 mmol) and water (50 mL) were added and stirred to dissolve, heated to 100 degrees to reflux for 10 hours until the reaction was complete. The reaction was cooled to room temperature, extracted with ethyl acetate (100 mL) three times. The organic phase was combined, washed with water (100 mL) once, dried with sodium sulfate, filtered. The filtrate was concentrated to dryness to obtain compound 7 (9.9 g, yield 95%) as a white solid.

[0401] LC-MS: [ESI] [M+H] + = 348.4.

[0402] 1 H NMR (400 MHz, DMSO-d6) δ 11.20 (br, 1H), 7.57 - 7.59 (m, 2H), 6.61 (d, J = 8.0 Hz, 1H), 6.27 (s, 2H), 4.71 (s, 2H), 4.01 - 4.04 (m, 3H), 2.13 (s, 6H), 1.54 (d, J = 7.2 Hz, 3H) ppm.

[0403] Step 6 Synthesis of compound 9: (S)-(2-cyano-2-((3,5-dimethyl-4-((3-((S)-1,1,1- trifluoropropyl-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)diazenyl)acetyl)aminoformic acid ethyl ester

[0404] Compound 7 (9.0 g, 25.9 mmol) was dissolved in concentrated hydrochloric acid (20 mL), cooled to 0 °C, and a solution of sodium nitrite (3.58 g, 51.9 mmol) in water (10 mL) was added dropwise at 0-5 °C. The reaction was continued for 1 hour at 0-5 °C. Then pyridine (5.0 mL) and ethyl (2-cyanoacetyl)carbamate (8.1 g, 51.8 mmol) were added successively, and the reaction was continued for 1 hour at 0-5 °C. The reaction solution was filtered, and the solid was collected and dried to give yellow solid compound 9 (10.7 g, yield 80%)

[0405] LC-MS: [ESI] [M+H] = 515.2. +

[0406] 1 H NMR (400 MHz, DMSO-d6) δ 12.00 (br, 1H), 11.30 (br, 1H), 10.47 (s, 1H), 7.65 (br, 2H), 7.42 (s, 2H), 6.72 (d, J = 8.0 Hz, 1H), 4.20-4.23 (m, 4H), 4.10-4.15 (m, 1H), 2.35 (s, 6H), 1.55 (d, J = 8.0 Hz, 3H), 1.28 (t, J = 8.0 Hz, 3H) ppm.

[0407] Seventh step Synthesis of compound 1: (S)-2-(3,5-dimethyl-4-((3-(1,1,1- trifluoropropan-2-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)methyl)phenyl)-3,5-dioxo-2,3,4,5- tetrahydro-1,2,4-triazine-6-carbonitrile

[0408] Compound 9 (10.0 g, 19.5 mmol) was dissolved in acetic acid (50 mL) and sodium acetate (3.2 g, 39.0 mmol) was added. The reaction was heated to 40 °C for 24 hours until the reaction was complete. The reaction was cooled to room temperature, water (200 mL) was added, and the mixture was extracted with ethyl acetate (200 mL) three times. The organic phase was combined, washed with brine (200 mL) once, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated to dryness to give yellow amorphous semi-oily compound 1 (7.6 g, yield 83%)

[0409] LC-MS: [ESI] [M+H] = 469.2. +

[0410] 1 ​​H NMR (400 MHz, DMSO-d6) δ 11.26 (s, 1H), 7.62 (t, J = 8.4 Hz, 2H), 7.12 (s, 2H), 6.70 (d, J = 8.4 Hz, 1H), 4.23 (s, 2H), 4.01 - 4.08 (m, 1H) 2.34 (s, 6H), 1.53 (d, J = 7.6 Hz, 3H) ppm.

[0411] 13 C NMR (100 MHz, DMSO-d6) δ 154.8, 151.4, 147.2, 143.9, 138.5, 137.7, 137.0, 127.4, 127.8 (q, J = 280 Hz), 126.9, 124.7, 122.0, 119.3, 115.2, 112.6, 109.4, 37.4, 33.6 (q, J = 30), 20.1, 14.1 ppm.

[0412] While the specific embodiments of the application have been described above, it will be understood by those skilled in the art that various modifications and changes can be made thereto without departing from the spirit and scope of the application. Accordingly, the scope of the application should be limited only by the appended claims.

Claims

A crystalline form A of a compound of Formula 1, characterized by: The X-ray powder diffraction pattern thereof has characteristic diffraction peaks at the following 2Θ angles: 9.70°±0.20°, 13.53°±0.20°, 16.62°±0.20°, 19.51°±0.20°, 21.44°±0.20° and 23.02°±0.20°; A crystalline Form A of the compound of Formula 1 according to claim 1, characterized in that, which satisfies one or more of the following conditions: (1) the X-ray powder diffraction pattern of the crystalline Form A of the compound of Formula 1 expressed in terms of 2θ angles further has diffraction peaks at one or more of the following 2θ angles: 8.77°±0.20°, 12.09°±0.20°, 15.54°±0.20°, 17.62°±0.20°, 18.01°±0.20° and 24.11°±0.20°; Preferably, it has an X-ray powder diffraction pattern, expressed in terms of 2 theta angles, with peak heights as shown below, where the error range is ±0.20° in 2 theta: Preferably, the crystalline Form A of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles substantially as shown in FIG.

1. (2) the thermogravimetric analysis of the crystalline Form A of the compound of Formula 1 shows a weight loss of 0.1% at 120°C; preferably, the thermogravimetric analysis thereof is substantially as shown in FIG. 3; and (3) the differential scanning calorimetry of the crystalline Form A of the compound of Formula 1 has an endothermic peak at 307.7°C±2.0°C; preferably, the differential scanning calorimetry thereof is substantially as shown in FIG.

2. A crystalline form D of a compound of Formula 1, characterized by: which has an X-ray powder diffraction pattern having characteristic diffraction peaks at the following 2θ angles: 8.22°±2.0°, 12.43°±2.0°, 20.24°±2.0° and 24.52°±2.0°. A crystalline Form D of the compound of Formula 1 according to claim 3, characterized in that, which satisfies one or more of the following conditions: (1) the X-ray powder diffraction pattern of the crystalline Form D of the compound of Formula 1 expressed in terms of 2θ angles further has diffraction peaks at one or more of the following 2θ angles: 9.16°±2.0°, 9.44°±2.0°, 16.24°±2.0°, 16.52°±2.0°, 16.99°±2.0° and 27.50°±2.0°; Preferably, The X-ray powder diffraction pattern in terms of peak height at 2 theta angle is shown below, where the error range in 2 theta is ±0.20°: Preferably, the crystalline Form D of the compound of Formula 1 has an X-ray powder diffraction pattern expressed in terms of 2θ angles substantially as shown in FIG.

10. (2) the thermogravimetric analysis of the crystalline Form D of the compound of Formula 1 shows a weight loss of 1.42% at 120°C; preferably, the thermogravimetric analysis thereof is substantially as shown in FIG. 12; and (3) the differential scanning calorimetry of the crystalline Form D of the compound of Formula 1 has three endothermic peaks at 25.6°±2.0°C, 90°±2.0°C and 311.6°±2.0°C, and one exothermic peak at 253.0°±2.0°C; preferably, the differential scanning calorimetry thereof is substantially as shown in FIG.

11. A method for preparing a crystalline form A of a compound represented by formula 1, characterized by, which comprises the following steps: adding a solution of the compound of Formula 1 and a solvent into water to crystallize, to obtain the crystalline Form A of the compound of Formula 1. wherein the solvent is an amide solvent. A method for preparing the crystalline form A of the compound of formula 1 according to claim 5, characterized in that, which satisfies one or more of the following conditions: (1) the amide solvent is N,N-dimethylformamide (DMF) and / or dimethylacetamide (DMAc); (2) the compound of Formula 1 is an amorphous compound of Formula 1 or a crystalline Form D of the compound of Formula 1; (3) the mass / volume ratio of the compound of Formula 1 to the solvent is 0.01-0.3 g / mL, for example, 0.1-0.16 g / mL; (4) the volume ratio of water to the solvent is 1:(1-30), for example, 1:(1-12.5); (5) the water is added dropwise; (6) the crystallization can comprise a post-treatment, which can include stirring, filtration and drying; (7) when the compound of Formula 1 is in the D crystal form of the compound of Formula 1, the mass to volume ratio of the compound of Formula 1 to the solvent is 0.16 g / mL; and (8) when the compound of Formula 1 is in the D crystal form of the compound of Formula 1, the volume ratio of water to the solvent is 1:12.

5. A method for preparing a crystalline form D of a compound of formula 1, characterized in that, which comprises the following step: crystallizing a suspension of the compound of Formula 1 and an alcoholic solvent to obtain the crystal form D of the compound of Formula 1. A process for preparing crystalline Form D of the compound of Formula 1 as claimed in claim 7, characterized in that, which satisfies one or more of the following conditions: (1) the compound of Formula 1 is an amorphous compound; (2) the alcoholic solvent is methanol; (3) the mass to volume ratio of the compound of Formula 1 to the alcoholic solvent is 0.01-0.3 g / mL, for example, 0.1 mg / mL; and (4) the temperature for crystallizing the suspension is 30-70 °C, for example, 50 °C. Use of a substance A in the preparation of a THR-β selective agonist, the substance A being the crystal form A of the compound of Formula 1 according to any one of claims 1-2 or the crystal form D of the compound of Formula 1 according to any one of claims 3-4; the substance A can be in a therapeutically effective amount. Use of a substance A in the preparation of a medicament, the medicament being a medicament for treating and / or preventing metabolic diseases or cardiovascular diseases, the metabolic diseases preferably being non-alcoholic steatohepatitis (NASH), liver steatosis, hyperlipidemia, thyroid diseases, obesity, hypercholesterolemia and diabetes, more preferably obesity, hyperlipidemia, hypercholesterolemia and diabetes, the thyroid diseases preferably being hypothyroidism and thyroid cancer, the cardiovascular diseases preferably being atherosclerosis; or, the medicament being a medicament for treating and / or preventing diseases mediated or associated with selective agonizing THR-β, for example, a medicament for treating and / or preventing metabolic diseases and cardiovascular diseases, the metabolic diseases preferably being liver steatosis, non-alcoholic steatohepatitis (NASH), obesity, atherosclerosis, hyperlipidemia and thyroid diseases, the thyroid diseases preferably being hypothyroidism and thyroid cancer; the substance A being the crystal form A of the compound of Formula 1 according to any one of claims 1-2 or the crystal form D of the compound of Formula 1 according to any one of claims 3-4; the substance A can be in a therapeutically effective amount. A method for preparing a compound of formula 1, characterized in that, It comprises the following steps: The compound of Formula 1 is obtained by reacting a compound of Formula 9 with an inorganic base in a solvent. The production method as claimed in claim 11, characterized in that which satisfies one or more of the following conditions: (1) the solvent is a polar solvent, preferably one or more of methanol, ethanol, tetrahydrofuran and acetic acid, for example, acetic acid; (2) the mass to volume ratio of the compound of Formula 9 to the solvent is 1:(3-10) g / mL, for example, 1:5 g / mL; (3) the inorganic base is one or more of sodium hydroxide, potassium carbonate and sodium acetate, for example, sodium acetate; (4) the molar ratio of the compound of Formula 9 to the inorganic base is 1:(1-5), for example, 1:2; (5) the temperature for the reaction is 30-70 °C, for example, 40 °C; and (6) the reaction further comprises a post-treatment after the reaction is completed, the post-treatment step comprising extraction, drying, filtration and concentration. The production method as claimed in claim 12, characterized in that The method for preparing the compound shown in formula 1 further comprises the following steps: The compound shown as formula 7 is diazotized in a solvent under the action of an inorganic acid and a nitrite or nitrite ester, and then coupled with a compound shown as formula 8 under the action of a base to obtain a compound shown as formula 9; Preferably, it satisfies one or more of the following conditions: (a) the inorganic acid is concentrated hydrochloric acid and / or concentrated sulfuric acid, for example, concentrated hydrochloric acid; (b) the molar ratio of the compound shown as formula 7 to the nitrite or nitrite ester is 1:(1-5), for example, 1:2; (c) the nitrite ester is isoamyl nitrite or tert-butyl nitrite, for example, isoamyl nitrite; (d) the nitrite is an aqueous solution of sodium nitrite, potassium nitrite or an alcohol solution of sodium nitrite, potassium nitrite, which can be methanol; (e) the nitrite ester is a mixed solution of a nitrite ester and a polar solvent, which can be one or more of methanol, tetrahydrofuran and acetonitrile, for example, acetonitrile; (f) the temperature of the diazotization reaction is 0-5℃; (g) the molar ratio of the compound shown as formula 7 to the compound shown as formula 8 is 1:(1-5), for example, 1:2; and (h) the temperature of the coupling reaction is 0-5℃. The production method as claimed in claim 13, characterized in that The method for preparing the compound shown in formula 1 further comprises the following steps: The compound shown as formula 6 is deprotected in a solvent under the action of an inorganic base and water or other deprotecting group conditions to obtain a compound shown as formula 7; R 2 N-protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts; Preferably, it satisfies one or more of the following conditions: (a) the solvent is an alcohol solvent, for example, methanol; (b) the mass-volume ratio of the solvent to the compound shown as formula 6 is 1:(3-10) g / mL, for example, 1:6.7 g / mL; (c) the molar ratio of the compound shown as formula 6 to the inorganic base is 1:(2-7), for example, 1:4.6; (d) the temperature of the deprotection reaction is 20-120℃, for example, 100℃; and (e) the reaction further comprises a post-treatment after the reaction is completed, the post-treatment step being extraction, drying, filtration and concentration. The production method as claimed in claim 14, characterized in that The method for preparing the compound shown in formula 1 further comprises the following steps: The compound shown as formula 5 is deprotected in a solvent under the action of an acid or other deprotecting group conditions to obtain a compound shown as formula 6; R 2 N-protecting group, such as Boc, Bn, Cbz, Fmoc, TBS or -Ts, for example -Ts; R 1 N-protecting group, such as Ts, Bn, Cbz, Fmoc, Ac or -Boc, for example -Boc; Preferably, it satisfies one or more of the following conditions: (a) the solvent is an ether solvent, which can be dioxane; (b) the mass-volume ratio of the solvent to the compound shown as formula 5 is 1:(3-10) g / mL, for example, 1:6.7 g / mL; (c) the acid is an organic acid or an inorganic acid, which is preferably one or more of TFA, acetic acid and hydrochloric acid, for example, hydrochloric acid; and (d) the deprotection reaction further comprises a post-treatment, the post-treatment step being concentration, pH adjustment and filtration. The production method as claimed in claim 15, characterized in that The method for preparing the compound shown in formula 1 further comprises the following steps: The compound shown as formula 4 is reduced in a solvent under the action of a ruthenium catalyst or a rhodium catalyst and an organic phosphine or organic amine ligand under the action of hydrogen or other reducing agent, to obtain the compound shown as formula 5; Preferably, it satisfies one or more of the following conditions: (a) the solvent is an alcohol solvent, for example, methanol; (b) the mass volume ratio of the solvent and the compound of formula 4 is 1:(3-30) g / mL, for example 1:25 g / mL; (c) the ruthenium catalyst is Ru(methylallyl)2(COD) and / or [Ru(p-cymene)Cl2]2, for example [Ru(p-cymene)Cl2]2; (d) the rhodium catalyst is Rh(NBD)2BF4and / or Rh(COD)2BF4; (e) the organic phosphine ligand is 1,1'-binaphthalene-2,2'-diphenylphosphine (R-BINAP); (f) the molar ratio of the catalyst and the organic phosphine ligand is 1:(1-2.5), for example 1:2; (g) the molar ratio of the catalyst and the compound of formula 4 is 0.01-0.2, for example 0.1; (h) the reaction is replaced with an inert gas, which can be nitrogen; (i) the temperature of the reduction reaction is 20-60°C; and (j) the deprotection reaction further comprises a post-treatment, which can be filtration, concentration and column chromatography purification. The production method as claimed in claim 16, characterized in that The method for preparing the compound shown in formula 1 further comprises the following steps: The compound of formula 3 and the compound of formula 2 are reacted to obtain compound 4 in a solvent under the action of a palladium catalyst and a base; R 2 N-protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts; R 1 N-protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc; Preferably, it satisfies one or more of the following conditions: (a) the solvent is a mixed solution of an ether solvent and water, the ether solvent is dioxane; the volume ratio of the ether solvent and water can be (1-5):1, for example 2:1; preferably, the solvent is a mixed solution of dioxane and water with a volume ratio of 2:1; (b) the mass volume ratio of the solvent and the compound of formula 2 is 1:(3-20) g / mL, for example 1:15 g / mL; (c) the molar ratio of the compound of formula 2 and the compound of formula 3 is 1-1.5, for example 1.25; (d) the molar ratio of the palladium catalyst and the compound of formula 2 is 0.01-0.2, for example 0.1; (e) the molar ratio of the compound of formula 2 and the base is 1:(2-5), for example 1:3; (f) the palladium catalyst is Pd(dppf)Cl2; (g) the base is potassium phosphate; (h) the reaction is replaced with an inert gas, which can be nitrogen; (i) the temperature of the reaction is 100-160°C; and (j) the reaction further comprises a post-treatment after the reaction, which can include extraction, drying, filtration, concentration and column chromatography purification. The production method as claimed in claim 17, characterized in that The method for preparing the compound shown in formula 1 further comprises the following steps: The compound of formula 3-1 is reacted to obtain the compound of formula 3 in a solvent under the action of bis[(pinacolato)borato]methane, an inorganic base and a palladium catalyst; R 1 N-protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc; (a) the solvent is a polar organic solvent, preferably an ether solvent, for example dioxane; (b) the mass volume ratio of the solvent and the compound of formula 3-1 is 1:(3-10) g / mL, for example 1:5 g / mL; (c) the molar ratio of the compound of formula 3-1 and bis[(pinacolato)borato]methane is 1:(1-2), for example 1:1.1; (d) the inorganic base is potassium hydroxide; (e) the palladium catalyst is Pd[P(t-Bu)3]2; (f) the molar ratio of the palladium catalyst to the compound of formula 3-1 is 0.01-0.2, preferably 0.01-0.1, for example 0.04; (g) the reaction is replaced with inert gas, which can be nitrogen; and (h) the reaction includes a work-up step after the reaction is completed, which work-up step includes extraction, drying, filtration, concentration and column chromatography purification. A compound of the following formula: R 2 N-protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts; R 1 N-protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc. A method of preparing a compound as claimed in claim 19, characterised in that ， A process for the preparation of a compound of formula 3 as claimed in claim 19 comprising the steps of: The compound of formula 3-1 is reacted to form a compound of formula 3 in a solvent in the presence of bis[(pinacolato)boron]methyl, an inorganic base and a palladium catalyst. Preferably, the operations and reaction conditions of the method for preparing the compound of formula 3 are as described in claim 18. R 1 N-protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc; The compound of formula 3 is reacted with the compound of formula 2 in the presence of a palladium catalyst and a base in a solvent to form compound 4. A process for the preparation of a compound of formula 4 as claimed in claim 19 comprising the steps of: Preferably, the operations and reaction conditions of the method for preparing the compound of formula 4 are as described in claim 17. R 2 N-protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts; R 1 N-protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc; The compound of formula 4 is reduced to form the compound of formula 5 in the presence of a ruthenium catalyst or a rhodium catalyst and an organic phosphine or an organic amine ligand in a solvent in the presence of hydrogen or other reducing agent. A process for the preparation of a compound of formula 5 as claimed in claim 19 comprising the steps of: Preferably, the operations and reaction conditions of the method for preparing the compound of formula 5 are as described in claim 16. The compound of formula 5 is deprotected to form the compound of formula 6 in the presence of an acid or other deprotection conditions in a solvent. A process for the preparation of a compound of formula 6 as claimed in claim 19, comprising the steps of: Preferably, the operations and reaction conditions of the method for preparing the compound of formula 6 are as described in claim 15. R 2 N-protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts; R 1 N-protecting group, such as -Ts, -Bn, -Cbz, -Fmoc, -Ac or -Boc, for example -Boc; The compound of formula 6 is deprotected to form the compound of formula 7 in the presence of an inorganic base and water or other deprotection conditions in a solvent. A process for the preparation of a compound of formula 7 as claimed in claim 19, comprising the steps of: Preferably, the operations and reaction conditions of the method for preparing the compound of formula 7 are as described in claim 14. R 2 N-protecting group, such as -Boc, -Bn, -Cbz, -Fmoc, -TBS or -Ts, for example -Ts; The compound of formula 7 is diazotized in the presence of an inorganic acid and sodium nitrite or nitrite ester, and then coupled with the compound of formula 8 in the presence of a base to form the compound of formula 9. A process for the preparation of a compound of formula 9 as claimed in claim 19 comprising the steps of: Preferably, the operations and reaction conditions of the method for preparing the compound of formula 7 are as described in claim 13. ​ ​

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