Use of hypoxanthine compounds in the preparation of a medicament for the treatment of pulmonary fibrosis

Abstract

The present invention discloses the use of hypoxanthine compound in the preparation of medicaments for treating pulmonary fibrosis, and relates to the technical field of biological medicine. In the use of hypoxanthine compound in the preparation of medicaments for treating pulmonary fibrosis, through the detection of the pharmacological activity of hypoxanthine compound undergoing structural modification and transformation for treating pulmonary fibrosis, the pharmacological activity of such compound is tested in various animal disease models, and the activity of preventing and treating different types of pulmonary fibrosis is provided, which proves that all of the hypoxanthine compounds have good activity and are obviously superior to the positive drug nintedanib and analogs A, B, C and D usually used in clinics and other hypoxanthine analogs in the prior art. The use of hypoxanthine compound in the preparation of medicaments for treating pulmonary fibrosis can provide a new framework for screening new compounds for preparing medicaments for treating pulmonary fibrosis, and lay the theoretical foundation for the development of new lead compounds.

Description

[Technical field]

[0001] The present invention relates to the technical field of biological medicines, in particular to the use of hypoxanthine compounds in the preparation of a medicament for the treatment of pulmonary fibrosis. [Background technology]

[0002] Pulmonary fibrosis has various etiologies, and the clinical pathological symptoms of pulmonary fibrosis generally include fibroblast proliferation, large amounts of extracellular matrix aggregates, inflammatory responses, and destruction of lung tissue structure. The mortality rate of pulmonary fibrosis is very high, even higher than most tumors; and the average survival time after pulmonary fibrosis is confirmed is 2.8 years. Pneumonia progresses and eventually develops into pulmonary fibrosis; these are different symptoms at different stages of progression of the same type of disease; exacerbation of interstitial pneumonia or other types of pneumonia are characterized by pulmonary fibrosis. Therefore, it is extremely important for the prevention and treatment of pneumonia and pulmonary fibrosis to discover drugs that can prevent and treat pneumonia and pulmonary fibrosis, alleviate pulmonary inflammatory responses, and prevent mild pneumonia from progressing to pulmonary fibrosis as severe pneumonia.

[0003] Hypoxanthine, also known as "6-hypoxanthine", is a naturally occurring purine compound and a synthetic precursor of purine nucleotides in nucleic acids. Currently, there are no reports of hypoxanthine compounds that can prevent the progression to pulmonary fibrosis and reverse pathological damage. Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to provide the use of hypoxanthine compound in the preparation of drugs for treating pulmonary fibrosis, and to accelerate the research and development process of new drugs for treating pulmonary fibrosis. Hereinafter, many technical effects that can be obtained by the preferred technical solution of the present invention will be described in detail. In order to achieve the above object, the present invention provides the following technical solution: [Means for solving the problem]

[0005] A first aspect of the present invention relates to the use of a hypoxanthine compound in the preparation of a medicament for the treatment of pulmonary fibrosis, said hypoxanthine compound having activity for treating pulmonary fibrosis, said hypoxanthine compound having one of the following structures: [ka] R1 is optionally O, N, C, S or =O; R2, R3 and R4 are optionally H, C1-C 18 Alkyl, halogen substituted C1-C 18 Alkyl, trifluoromethyl, sulfonyl, sulfonamide, sulfinyl, amino acid group, 2-[bis[(pivaloyloxy)methoxy]phosphinyl]methoxy]ethyl, C1-C 18 Fatty acid group, C3-C 12 Heterocyclyl and C1-C 18 or R2, R3 and R4 are optionally C1-C 18 alkyl or a fatty acid group substituted with an oxygen atom, a sulfur atom or a nitrogen atom; and R3 and R4, when monosubstituted, are attached to the unsubstituted N position via a double bond, and when fully substituted, have no double bond.

[0006] A second aspect of the present invention relates to a compound having the structure: [ka] R1 is optionally O, N, C, S or =O; R2, R3 and R4 are optionally H, C1-C 18 Alkyl, halogen substituted C1-C 18 Alkyl, trifluoromethyl, sulfonyl, sulfonamide, sulfinyl, amino acid group, 2-[bis[(pivaloyloxy)methoxy]phosphinyl]methoxy]ethyl, C1-C 18 Fatty acid group, C3-C 12 Heterocyclyl and C1-C 18 or R2, R3 and R4 are optionally C1-C 18alkyl or a fatty acid group substituted with an oxygen atom, a sulfur atom or a nitrogen atom; and R3 and R4, when monosubstituted, are attached to the unsubstituted N position via a double bond, and when fully substituted, have no double bond.

[0007] According to one preferred embodiment, the compound is selected from the following group: [ka]

[0008] A third aspect of the present invention relates to a pharmaceutical composition comprising a compound of the present invention, or a pharma- ceutically acceptable salt thereof.

[0009] According to a preferred embodiment, the pharmaceutical composition further comprises a pharma- ceutically acceptable excipient or auxiliary ingredient.

[0010] According to a preferred embodiment, the pharmaceutical composition is an oral agent, an injectable agent, or an agent for nasal administration.

[0011] A fourth aspect of the present invention relates to a method for treating pulmonary fibrosis, the method comprising administering to a subject in need thereof an effective amount of a compound or a pharma- ceutically acceptable salt thereof, or a pharmaceutical composition of the present invention.

[0012] According to a preferred embodiment, the drug for treating pulmonary fibrosis includes drugs having efficacy in preventing and treating pulmonary fibrosis and its complications.

[0013] According to a preferred embodiment, the drug for treating pulmonary fibrosis is a formulation prepared by using a hypoxanthine compound or a salt thereof as an active ingredient in combination with a pharma- ceutically acceptable excipient or auxiliary ingredient.

[0014] According to a preferred embodiment, the formulation is an oral, injectable, or nasal formulation.

[0015] According to a preferred embodiment, the pulmonary fibrosis comprises one or more of primary pulmonary fibrosis, secondary pulmonary fibrosis, idiopathic pulmonary fibrosis, pulmonary interstitial fibrosis and interstitial pneumonia.

[0016] According to a preferred embodiment, the pulmonary fibrosis comprises one or more of bacterial pulmonary fibrosis, viral pulmonary fibrosis, mycoplasmal pulmonary fibrosis, chlamydial pulmonary fibrosis, immune pulmonary fibrosis and fungal pulmonary fibrosis.

[0017] According to a preferred embodiment, the pulmonary fibrosis comprises one or more of Streptococcus pneumoniae-induced pulmonary fibrosis, influenza A virus-induced pulmonary fibrosis, influenza B virus-induced pulmonary fibrosis, coronavirus-induced pulmonary fibrosis, and novel coronavirus-induced pulmonary fibrosis.

[0018] According to a preferred embodiment, the pulmonary fibrosis further comprises one or more of Klebsiella pneumoniae-induced pulmonary fibrosis, Streptococcus pneumoniae-induced pulmonary fibrosis, vancomycin-resistant Enterococcus-induced pulmonary fibrosis, drug-resistant Staphylococcus aureus-induced pulmonary fibrosis, and Acinetobacter baumannii-induced pulmonary fibrosis.

[0019] Term definition: The compounds and derivatives thereof provided by the present invention may be named according to the International Union of Pure and Applied Chemistry (IUPAC) or Chemical Abstracts Service (CAS, Columbus, Ohio) nomenclature systems.

[0020] The term "alkyl" refers to a straight or branched chain saturated hydrocarbyl group. Examples of C1-C3 alkyl include methyl (C1), ethyl (C2), n-propyl (C3), and isopropyl (C4).

[0021] The term "pharmaceutical acceptable" means that a particular carrier, vehicle, diluent, accessory and / or forming salt is generally chemically or physically compatible with the other ingredients that make up a particular pharmaceutical dosage form and is physiologically compatible with the recipient.

[0022] The term "pharmaceutically acceptable salts" refers to acidic and / or basic salts formed by the compounds of the present invention and inorganic and / or organic acids and bases, including zwitterionic salts (internal salts) and further including quaternary ammonium salts, such as alkylammonium salts. These salts can be obtained directly during the final isolation and purification of the compounds; they can also be obtained by appropriately mixing the compounds with an amount (e.g., equal equivalents) of an acid or base. These salts can be collected by the formation of a precipitate in solution and filtration of the precipitate, can be recovered after evaporation of the solvent, or can be prepared by reaction in an aqueous medium followed by freezing and drying. The salts of the present invention can be the hydrochloride, sulfate, citrate, benzenesulfonate, hydrobromide, hydrofluoride, phosphate, acetate, propionate, succinate, oxalate, malate, succinate, fumarate, maleate, tartrate, or trifluoroacetate salts of the compounds.

[0023] The administration form of the compound or pharmaceutical composition of the present invention is not particularly limited; representative administration forms include (but are not limited to): oral administration, parenteral administration (intravenous, intramuscular, subcutaneous) and topical administration.

[0024] Oral solid formulations include capsules, tablets, pills, powders and granules. In these solid formulations, the active compound is mixed with at least one conventional inert excipient (or carrier), such as sodium citrate or dicalcium phosphate, or with the following ingredients: (a) a filler or solubilizer, such as starch, lactose, sucrose, mannitol and silicic acid; (b) an adhesive, such as hydroxymethylcellulose, alginate, gelatin, polyvinylpyrrolidone, sucrose and gum arabic; (c) a humectant, such as glycerol; (d) a disintegrant, such as agar. , calcium carbonate, potato or tapioca starch, alginic acid, certain silicic acids and sodium carbonate; (e) retarding solvents such as paraffin; (f) absorption accelerators such as quaternary ammonium compounds; (g) wetting agents such as cetyl alcohol and glyceryl monostearate; (h) adsorbents such as kaolin; and (i) lubricants such as talc, calcium stearate, magnesium stearate, solid polyethylene glycol, sodium lauryl sulfate, or mixtures thereof. In the case of capsules, tablets and pills, the dosage form may further comprise buffering agents.

[0025] Solid dosage forms, such as tablets, sugar pills, capsules, pills and particles, can be prepared by using coatings and shells, such as casings and other materials well known in the art.Solid dosage forms can include opacifying agents, and the active compound or compounds in such compositions can be released in a delayed manner in a certain part of the digestive tract.Examples of the embedding components that can be used include polymeric and waxy materials.If necessary, the active compound can be further formed into microcapsules with one or more of the above-mentioned excipients.

[0026] Liquid dosage forms for oral administration include pharma- ceutically acceptable emulsions, solutions, suspensions, syrups, or tinctures. In addition to the active compound, liquid dosage forms contain conventionally used inert diluents, such as water or other solvents, solubilizers, and emulsifiers, such as ethyl alcohol, isopropanol, ethyl carbonate, ethyl acetate, polypropylene glycol, 1,3-butanediol, dimethylformamide, or oils, in particular cottonseed oil, peanut oil, corn germ, olive oil, castor oil, sesame oil, or mixtures thereof.

[0027] Besides these inert diluents, the composition can also include adjuvants, such as wetting agents, emulsifying and suspending agents, sweetening, perfumery and flavoring agents.

[0028] In addition to the active compounds, suspensions may contain suspending agents such as ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and polyoxyethylene sorbitan esters, microcrystalline cellulose, aluminum methoxide, and agar, or mixtures thereof.

[0029] Compositions for parenteral injection may include physiologically acceptable sterile aqueous or non-aqueous solutions, dispersions, suspensions or emulsions, and sterile powders for reconstitution into sterile injectable solutions or dispersions. Suitable aqueous or non-aqueous carriers, diluents, solvents or excipients include water, ethyl alcohol, polyols, and suitable mixtures thereof.

[0030] The dosage forms of the compounds of the present invention for topical administration include ointments, powders, patches, sprays and inhalants, for example, for nasal administration. The active ingredient is mixed under sterile conditions with a physiologically acceptable carrier, and any preservatives and buffers, or any propellants required as required.

[0031] Pharmaceutically acceptable excipients according to the present invention refer to other substances that are contained in the dosage form in addition to the active ingredients.

[0032] The pharma- ceutically acceptable auxiliary components of the present invention have certain physiological activities. However, the addition of such auxiliary components does not change the main role of the pharmaceutical composition in the disease treatment process, and the auxiliary components can only exert auxiliary effects. The auxiliary effects are only produced by utilizing the known activity of the auxiliary components. When the auxiliary components are combined with the pharmaceutical composition of the present invention, they should still fall within the scope of protection of the present invention.

[0033] The hypoxanthine compounds provided by the present invention have at least the following beneficial effects: In the use of hypoxanthine compound in the preparation of the drug for resisting pulmonary fibrosis provided by the present invention, through the detection of the pharmacological activity of the hypoxanthine compound subjected to structural modification and transformation for treating pulmonary fibrosis, the pharmacological activity of such compound is tested in various animal disease models, and the activity of preventing and treating different types of pulmonary fibrosis is provided, which proves that all of the hypoxanthine compounds have good activity, and have obviously better effect than the positive drug nintedanib and analogs A, B, C and D commonly used in clinics, as well as other hypoxanthine analogs in the prior art.That is, the use of hypoxanthine compound in the preparation of the drug for resisting pulmonary fibrosis provided by the present invention can provide a new framework for the screening of new compounds for preparing drugs for resisting pulmonary fibrosis, and lay the theoretical foundation for the development of new lead compounds.

[0034] Specifically, the use of the hypoxanthine compound in the preparation of a drug for combating pulmonary fibrosis provided by the present invention can significantly improve viral and bacterial pulmonary fibrosis.More importantly, the hypoxanthine compound provided by the present invention can improve the symptoms of early pulmonary fibrosis and the reverse symptoms of advanced pulmonary fibrosis. EXAMPLES

[0035] In order to clarify the objectives, technical solutions and advantages of the present invention, the technical solutions of the present invention are described in detail below.Obviously, the embodiments described in the present invention are only some embodiments, not all embodiments.Based on the embodiments of the present invention, those skilled in the art can make without creative efforts all other embodiments including the extension research in the hypoxanthine compound of the present invention in treating pulmonary fibrosis are included in the protection scope of the present invention.

[0036] Through medicinal chemistry and chemical research of natural products, many plant endogenous substances and derivatives have been developed. Through structural modification and conversion of natural products, many derivatives with excellent pharmacological activity can be obtained. In the use of hypoxanthine compound in the preparation of drugs for resisting pulmonary fibrosis provided by the present invention, through the detection of pharmacological activity for treating pulmonary fibrosis by the hypoxanthine compound subjected to structural modification and conversion, the pharmacological activity of such compounds is tested in various animal disease models, and data on the activity of preventing and treating different types of pulmonary fibrosis are provided, which prove that hypoxanthine compound has good activity and is obviously superior to the positive drug nintedanib and hypoxanthine analogs A, B, C and D usually used in clinics, as well as other hypoxanthine analogs in the prior art. That is, the use of hypoxanthine compound in the preparation of drugs for resisting pulmonary fibrosis provided by the present invention can provide a new framework for screening new compounds for preparing drugs for resisting pulmonary fibrosis, and lay the theoretical foundation for developing new lead compounds.

[0037] The structures of hypoxanthine analogs A, B, C and D are shown below, respectively. [ka]

[0038] Hypoxanthine analogs A, B, C and D are prepared by the following methods for preparing compound 2, compound 4 and / or compound 6. Next, the use of hypoxanthine compounds in the preparation of drugs for resisting pulmonary fibrosis provided by the present invention will be described in detail in combination with Examples 1-8.

[0039] Example 1 The preparation of compounds 1-12 is described in detail in this Example.

[0040] According to a preferred embodiment, compounds 1-12 are prepared by alkylation reaction of hypoxanthine.

[0041] This example provides the preparation methods of 12 compounds, the structures of which are all determined by nuclear magnetic resonance spectroscopy and mass spectrometry.

[0042] Preparation of Compound 1 and Compound 5 The synthetic routes to compound 1 and compound 5 are shown below: [ka]

[0043] Reaction: (1) 3.45g of sodium hydride (4.5 eq) was added into a 250mL four-necked bottle at 0°C, and after suction exchange of air three times, 40mL of (8V) anhydrous THF was slowly added under nitrogen atmosphere; (2) 12.3mL of isopropanol (4.5 eq) was slowly added dropwise to the system and reacted for 30 minutes; (3) Then, a mixture of 5g of compound 1 (1.0 eq) in 100mL of (20V) isopropanol was slowly added dropwise to the system; (4) The temperature was raised to 80°C, and the system was reacted for 10 hours.

[0044] Workup: (1) After the reaction was completed, the product was quenched with water, and acetic acid was added to neutralize it until the pH value was 8-10; (2) The product was extracted with ethyl acetate five times, and the organic phases were combined; (3) The combined organic phases were dried with anhydrous sodium sulfate, concentrated, and quickly separated by silica gel column chromatography to obtain a pale yellow solid; (4) Thin layer chromatography (TLC) monitoring: Developing solvent: dichloromethane / methyl alcohol=10:1 Rf (compound 1)=0.4 The relevant spectral data for compounds 1 and 5 are shown below. Compound 1: 1H NMR (400 MHz, DMSO-d6) δ 13.33 (s, 1H), 8.44 (s, 1H), 8.32 (s, 1H), 5.55 (hept, J = 6.1 Hz, 1H), 1.37 (d, J = 6.2 Hz, 6H). HRMS (ESI-TOF) calc'd for C8H10N4OH+ [M + H+]: 179.09; 179.10 was obtained. Compound 5: 11H NMR (400 MHz, DMSO-d6) δ 13.37 (s, 1H), 8.47 (s, 1H), 8.35 (s, 1H), 5.57 (hept, J = 6.2 Hz, 1H), 1.39 (d, J = 6.2 Hz, 6H). HRMS (ESI-TOF) [M + H+]: 179.09; got 179.00.

[0045] Preparation of Compound 2, Compound 4 and Compound 6 The synthetic routes to compounds 2, 4, and 6 are shown below: [ka]

[0046] The relevant spectral data for Compound 2, Compound 4, and Compound 6 are shown below: Compound 2: 1H NMR (400 MHz, chloroform-d) δ 13.19 (s, 1H), 8.24 (s, 1H), 7.89 (s, 1H), 4.80 (hept, J = 6.8 Hz, 1H), 1.60 (d, J = 6.8 Hz, 6H). HRMS (ESI-TOF) [M + H+]: 179.19; 179.30 was obtained. Compound 4: 1H NMR (400 MHz, chloroform-d) δ 8.58 (s, 1H), 8.07 (s, 1H), 5.63 (hept, J = 6.2 Hz, 1H), 4.90 (hept, J = 6.7 Hz, 1H), 1.59 (d, J = 6.8 Hz, 6H), 1.44 (d, J = 6.2 Hz, 6H). HRMS (ESI-TOF) [M + H+]: 221.27; 221.20 was obtained. Compound 6: 1H NMR (400 MHz, chloroform-d) δ 13.21 (s, 1H), 8.27 (s, 1H), 7.82 (s, 1H), 4.70 (hept, J = 6.8 Hz, 1H), 1.65 (d, J = 6.6 Hz, 6H). HRMS (ESI-TOF) [M + H+]: 179.19; 179.30 was obtained.

[0047] Preparation of compound 3 The synthetic route to compound 3 is shown below: [ka]

[0048] The relevant spectral data for compound 3 are shown below: Compound 3: 1H NMR (400 MHz, DMSO-d6) δ 8.43 (s, 1H), 8.19 (s, 1H), 5.08 (hept, J = 6.9 Hz, 1H), 4.71 (hept, J = 6.8 Hz, 1H), 1.52 (d, J = 6.8 Hz, 6H), 1.41 (d, J = 6.9 Hz, 6H). HRMS (ESI-TOF) [M + H+]: 221.27; 221.30 was obtained.

[0049] Preparation of compounds 7-12 Compounds 7-12 are prepared by the method described above for preparing one of compounds 1-6.

[0050] The relevant spectral data for compounds 7-12 are shown below: Compound 7: 1H NMR (500 MHz, chloroform-d) δ 8.58 (s, 1H), 7.99 (d, J = 0.9 Hz, 1H), 4.89 (heptd, J = 5.6, 0.5 Hz, 1H), 4.18 (s, 3H), 1.63 (s, 6H). HRMS (ESI-TOF) [M + H+]: 193.10; Compound 8: 1H NMR (500 MHz, chloroform-d) δ 8.55 (s, 1H), 7.95 (d, J = 0.9 Hz, 1H), 4.85 (heptd, J = 5.2, 0.5 Hz, 1H), 4.62 (q, J = 6.5 Hz, 2H), 1.57 (s, 3H), 1.50 (t, J = 6.5 Hz, 3H). HRMS (ESI-TOF) [M + H+]: 207.12; 207.10 was obtained. Compound 9: 1H NMR (500 MHz, chloroform-d) δ 8.51 (s, 1H), 7.57 (d, J = 0.3 Hz, 1H), 4.57 (heptd, J = 5.0, 0.7 Hz, 1H), 4.61 (t, J = 5.4 Hz, 2H), 1.90 (qt, J = 7.3, 5.9 Hz, 2H), 1.63 (s, 6H), 1.15 (t, J = 7.4 Hz, 3H). HRMS (ESI-TOF) [M + H+]: 221.13; 221.10 was obtained. Compound 10: 1H NMR (500 MHz, chloroform-d) δ 8.37 (s, 1H), 5.33 - 5.27 (m, 3H), 4.74 - 4.64 (m, 2H), 1.25 (d, J = 6.2 Hz, 6H), 1.17 (dd, J = 6.7, 5.2 Hz, 12H). HRMS (ESI-TOF) [M + H+]: 265.20; Compound 11: 1H NMR (500 MHz, chloroform-d) δ 7.99 - 7.88 (m, 2H), 4.83 (pd, J = 5.6, 0.8 Hz, 1H), 2.32 (s, 3H), 1.53 (s, 6H). HRMS (ESI-TOF) [M + H+]: 221.10; Compound 12: 1H NMR (500 MHz, chloroform-d) δ 7.99 - 7.90 (m, 2H), 4.85 (heptd, J = 5.2, 0.5 Hz, 1H), 2.54 (q, J = 7.7 Hz, 2H), 1.55 (s, 3H), 1.19 - 1.11 (m, 3H). HRMS (ESI-TOF) [M + H+]: 235.10;

[0051] Example 2 This example is used to detect the broad-spectrum pulmonary fibrosis-resistant activity of compounds 1 to 12 prepared in Example 1.

[0052] (1) Anti-early stage pulmonary fibrosis activity of compounds 1-12

[0053] Experimental Method: An in-vivo bleomycin-induced pulmonary fibrosis model was established: SPF class C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group, with 9 mice in each group, and fed in SPF class animal center for 7 days. The mice were fasted for 12 h before the experiment, and then anesthetized with sodium pentobarbital, and bleomycin (5 mg / kg) was inhaled into the lungs through the trachea by spontaneous breathing to induce pulmonary fibrosis; furthermore, the mice in the blank control group were given sterile PBS, and the mice in the model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group, compound 12 group, and compound 22 groups were given the equivalent of 5 mg / kg bleomycin. After the model was established for one week, the mice in each group were intragastrically administered for intervention; the mice in the blank control group and the model group were given the same weight and amount of saline as the drug-administered group according to body weight; the mice in the nintedanib positive control group were given an appropriate amount of nintedanib (120 mg / kg) according to body weight; the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. The mice were administered twice daily; after 14 days of administration, the mice were anesthetized with 0.8% sodium pentobarbital solution (10 mL / kg) on ​​the 15th day; blood was collected from the abdominal aorta to detect changes in blood routine and evaluate the severity of pulmonary fibrosis in the lung tissue; paraffin sections of the lung tissue were stained with HE and Ashcroft scoring were performed. The results are shown in Tables 2-1 and 2-2.

[0054] [Table 1]

[0055] From the data in Table 2-1, it can be seen that compounds 1 to 12 prepared in Example 1 have significant inhibitory effects on leukocytes, neutrophils, and lymphocytes in the blood of mice with early pulmonary fibrosis; on the other hand, the anti-inflammatory effects of nintedanib tablets, hypoxanthine analogue A, hypoxanthine analogue B, and hypoxanthine analogue C are obviously inferior to that of compounds 1 to 12.

[0056] From the data in Table 2-2, it is clear that the degree of pulmonary fibrosis in the pulmonary fibrosis model mice was significantly improved under the action of compounds 1 to 12 prepared in Example 1, which indicates that compounds 1 to 12 prepared in Example 1 have a significant pulmonary fibrosis resistance effect, and the improving effect is superior to that of nintedanib tablets, hypoxanthine analogue A, hypoxanthine analogue B and hypoxanthine analogue C.

[0057] (2) Anti-progressive pulmonary fibrosis activity of compounds 1-12

[0058] Experimental Method: An in-vivo bleomycin-induced pulmonary fibrosis model was established: SPF class C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group, with 9 mice in each group, and fed in SPF class animal center for 7 days. The mice were fasted for 12 h before the experiment, and then anesthetized with sodium pentobarbital, and bleomycin (5 mg / kg) was inhaled into the lungs through the trachea by spontaneous breathing to induce pulmonary fibrosis; furthermore, the mice in the blank control group were given sterile PBS, and the mice in the model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group were given the equivalent of 5 mg / kg bleomycin. After the model was established for three weeks, the mice in each group were intragastrically administered for intervention; the mice in the blank control group and the model group were given the same weight and amount of saline as the drug-administered group according to body weight; the mice in the nintedanib positive control group were given an appropriate amount of nintedanib (120 mg / kg) according to body weight; the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 3 group, the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. The mice were administered twice daily; after 14 days of administration, the mice were anesthetized with 0.8% sodium pentobarbital solution (10 mL / kg) on ​​the 15th day; blood was collected from the abdominal aorta to detect changes in blood routine and evaluate the severity of pulmonary fibrosis in the lung tissue; paraffin sections of the lung tissue were stained with HE and Ashcroft scoring were performed. The results are shown in Tables 2-3 and 2-4.

[0059] [Table 2]

[0060] From Table 2-3, it can be seen that compounds 1 to 12 prepared in Example 1 have significant inhibitory effects on leukocytes, neutrophils, and lymphocytes in the blood of mice with progressive pulmonary fibrosis; on the other hand, the anti-inflammatory effects of nintedanib tablets, hypoxanthine analogue A, hypoxanthine analogue B, and hypoxanthine analogue C are obviously inferior to that of compounds 1 to 12.

[0061] From Tables 2-4, it is clear that the degree of pulmonary fibrosis in the pulmonary fibrosis model mice was significantly improved under the action of compounds 1 to 12 prepared in Example 1, which indicates that compounds 1 to 12 prepared in Example 1 have a significant pulmonary fibrosis resistance effect, and the improving effect is superior to that of nintedanib tablets, hypoxanthine analogue A, hypoxanthine analogue B and hypoxanthine analogue C.

[0062] (3) Comparison of pulmonary fibrosis-resistant activities of compounds 1 to 12 and comparative drugs

[0063] The structures of hypoxanthine analogs A, B, C, and D as comparative drugs, and compounds E1 to E12 are shown below: [ka]

[0064] Hypoxanthine analogs A, B, C and D, and compounds E1-E12 are prepared by the following method for preparing compound 2, compound 4 and / or compound 6.

[0065] Experimental Method: An in-vivo bleomycin-induced pulmonary fibrosis model was established: SPF class C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, hypoxanthine analog D group, compound E1-E12 group, compound 1 group, compound 2 group-compound 12 group, with 9 mice per group, and fed in SPF class animal center for 7 days. The mice were fasted for 12 h before the experiment, and then anesthetized with sodium pentobarbital, and bleomycin (5 mg / kg) was inhaled into the lungs through the trachea by spontaneous breathing to induce pulmonary fibrosis; furthermore, the mice in the blank control group were given sterile PBS, and the mice in the model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, hypoxanthine analog D group, compound E1-E12 group, compound 1 group, compound 2 group-compound 12 group were given the equivalent of 5 mg / kg bleomycin. After the model was established for two weeks, the mice in each group were intragastrically administered for intervention; the mice in the blank control group and model group were given the same weight and amount of saline as the drug-treated groups according to body weight; the mice in the nintedanib positive control group were given an appropriate amount of nintedanib (120 mg / kg) according to body weight; the mice in the hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group and hypoxanthine analog D group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d), hypoxanthine analog C (120 mg / kg / d) and hypoxanthine analog D (120 mg / kg / d), respectively; Mice in the compound 1 group, compound 2 group to compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively; mice in the compound E1 group, compound E2 group to compound E12 group were given compound E1 (120 mg / kg / d), compound E2 (120 mg / kg / d) to compound E12 (120 mg / kg / d).The mice were administered twice daily; after 14 days of administration, on the 15th day, the mice were anesthetized with 0.8% sodium pentobarbital solution (10mL / kg); bronchoalveolar lavage fluid and lung tissue were collected to detect the concentration of hydroxyproline and TGF-β, which are the gold standard of pulmonary fibrosis, in bronchoalveolar lavage fluid and lung tissue. The pulmonary fibrosis resistance level of the present patent pending compound was evaluated. The results are shown in Tables 2-5.

[0066] [Table 3]

[0067] From the data in Table 2-5, through data analysis by one-way ANOVA, it can be seen that the hydroxyproline levels in the lung tissues of mice in the compound 1-12 intervention group are all significantly lower than those of the model control group (P<0.001); the hydroxyproline levels in the bronchoalveolar lavage fluid of mice in the compound 1-12 intervention group are all significantly lower than those of the model control group (P<0.05); the TGF-β levels in the lung tissues of mice in the compound 1-2 intervention group are all significantly lower than those of the model control group (P<0.05); the TGF-β concentrations in the bronchoalveolar lavage fluid of mice in the compound 1-12 intervention group are all significantly lower than those of the model control group (P<0.001). Importantly, the hydroxyproline levels in the lung tissues of mice in the compound 1-12 intervention group were all significantly lower than those in the hypoxanthine analogues A-D and compound E1-E12 control groups (P values ​​were all less than 0.05 and significant difference was observed for each group). The hydroxyproline levels in the bronchoalveolar lavage fluid of mice in the compound 1-2 intervention group were all significantly lower than those in the hypoxanthine analogues A-D and compound E1-E12 control groups (P values ​​were all less than 0.001 and significant difference was observed for each group). The TGF-β levels in the lung tissues of mice in the compound 1-12 intervention group were all significantly lower than those in the hypoxanthine analogues A-D and compound E1-E12 control groups (P values ​​were all less than 0.001 and significant difference was observed for each group). It can be further seen that the TGF-β concentrations in the bronchoalveolar lavage fluid of mice in the compound 1-12 intervention group are all significantly inferior to those of mice in the hypoxanthine analogues A-D and compound E1-E12 control groups (P values ​​are all less than 0.05 and significant differences are observed from the comparative statistical analysis of each group). These results show that the compounds 1-12 prepared in Example 1 have significant inhibitory effects on hydroxyproline and TGF-β in the bronchoalveolar lavage fluid and lung tissue of pulmonary fibrosis model mice; the pulmonary fibrosis inhibitory effects of nintedanib positive control, hypoxanthine analogue A, hypoxanthine analogue B, hypoxanthine analogue C, hypoxanthine analogue D, and compounds E1-E12 are obviously inferior to compounds 1-12.

[0068] From Tables 2-5, it can be clearly seen that the degree of pulmonary fibrosis in the pulmonary fibrosis model mice was significantly improved under the action of compounds 1 to 12 prepared in Example 1, which indicates that compounds 1 to 12 prepared in Example 1 have a significant pulmonary fibrosis resistance effect, and the improving effect is superior to that of nintedanib tablets, hypoxanthine analogue AD and compounds 1 to 12.

[0069] Example 3 In this example, compounds 1 to 12 prepared in Example 1 are used to detect the activity of compounds 1 to 12 against Streptococcus pneumoniae-induced pulmonary fibrosis.

[0070] Experimental Method: An in-vivo Streptococcus pneumoniae-induced pulmonary fibrosis model was established: SPF class C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group, with 9 mice per group, and fed for 7 days in an SPF class animal center. On the first day, the mice were lightly anesthetized by diethyl ether inhalation, and the mice in the blank control group were intranasally injected with normal saline; the mice in the other groups were intranasally injected with Streptococcus pneumoniae liquid (1.0 × 10 9CFU / mL) was inhaled into the lungs via the trachea by spontaneous breathing to induce pulmonary fibrosis. On day 2, the mice were given 5 mg / kg bleomycin via the trachea to induce pulmonary fibrosis. After the model was established for one week, the mice in each group were intragastrically administered for intervention; the mice in the blank control group and the model group were given the same weight and amount of saline as the drug-administered group according to body weight; the mice in the nintedanib positive control group were given an appropriate amount of nintedanib (120 mg / kg) according to body weight; the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. The mice were administered the drug three times daily; After administration for 14 days, the mice were anesthetized with 0.8% sodium pentobarbital aqueous solution (10 mL / kg) on ​​the 15th day; Blood was collected from the abdominal aorta to detect changes in blood routine and evaluate the severity of pulmonary fibrosis in the lung tissue; Paraffin sections of the lung tissue were stained with HE and scored by Ashcroft. The results are shown in Tables 3-1 and 3-2.

[0071] [Table 4]

[0072] From Table 3-1, it can be seen that compounds 1 to 12 prepared in Example 1 have significant inhibitory effects on leukocytes, neutrophils, and lymphocytes in the blood of mice with streptococcus pneumoniae-induced pulmonary fibrosis; on the other hand, the anti-inflammatory effects of nintedanib tablets, hypoxanthine analogue A, hypoxanthine analogue B, and hypoxanthine analogue C are obviously inferior to that of compounds 1 to 12.

[0073] From Table 3-2, it is clear that the degree of pulmonary fibrosis induced by Streptococcus pneumoniae is significantly improved under the action of compounds 1 to 12 prepared in Example 1, that is, the degree of pulmonary fibrosis is significantly reduced, which indicates that compounds 1 to 12 prepared in Example 1 have a significant pulmonary fibrosis resistance effect, and the improving effect is superior to that of nintedanib tablets, hypoxanthine analog A, hypoxanthine analog B and hypoxanthine analog C.

[0074] Example 4 In this example, compounds 1 to 12 prepared in Example 1 are used to detect the resistance activity against influenza A virus-induced pulmonary fibrosis.

[0075] Experimental Method: An in-vivo influenza A virus-induced pulmonary fibrosis model was established: C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group, with 9 mice per group. On day 1, the mice in the blank control group were intranasally instilled with normal saline, and the mice in the other groups were intranasally instilled with influenza A (H1N1) virus FM1 strain (30μL) to infect them all. On day 2, the mice were given 5mg / kg bleomycin via the trachea to induce pulmonary fibrosis. After the model was established for two weeks, the mice in each group were intragastrically administered with the same dose of saline as that of the drug administration group for 14 consecutive days to be intervened; the mice in the blank control group and the model group were intragastrically administered with saline at the same dose as that of the drug administration group; the mice in the nintedanib positive control group were given nintedanib (120 mg / kg); the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. After 14 days of continuous administration, the mice were observed every day, and the body weight and death status were recorded. After administration, blood was collected from the eyeballs to immediately detect the expression levels of NF-κB, TNF-α, IL-1 and IL-6 in the serum, and lung tissue was collected for HE staining and Ashcroft scoring. The results are shown in Tables 4-1 and 4-2.

[0076] [Table 5]

[0077] From the data in Table 4-1, it can be seen that the compounds 1-12 prepared in Example 1 have the effect of significantly reducing the levels of IL-1β, IL-6, TNF-α and NF-κB in serum, which shows that the compounds 1-12 have significant influenza A virus-induced pulmonary fibrosis resistance activity and show superior effects to hypoxanthine analog A, hypoxanthine analog B, hypoxanthine analog C and nintedanib. It can also be seen that there is no pulmonary fibrosis lesion in the lungs of the mice in the compound 1-12 intervention group.

[0078] From the data in Table 4-2, it can be seen that the compounds 1 to 12 prepared in Example 1 have the effect of significantly reducing the degree of influenza A virus-induced pulmonary fibrosis, which indicates that the compounds 1 to 12 have a significant improving effect on influenza A virus-induced pulmonary fibrosis, and are more effective than hypoxanthine analogue A, hypoxanthine analogue B, hypoxanthine analogue C and nintedanib tablets.

[0079] Example 5 In this example, compounds 1 to 12 prepared in Example 1 are used to detect the resistance activity against influenza B virus-induced pulmonary fibrosis.

[0080] Experimental Method: An in-vivo influenza B virus-induced pulmonary fibrosis model was established: C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group, with 9 mice per group. On day 1, the mice in the blank control group were intranasally instilled with normal saline, and the mice in the other groups were intranasally instilled with influenza B (H7N9) virus strain (30μL) to infect them all. On day 2, the mice were given 5mg / kg bleomycin via the trachea to induce pulmonary fibrosis. After the model was established for two weeks, the mice in each group were intragastrically administered with saline for 14 consecutive days to be intervened; the mice in the blank control group and the model group were intragastrically administered with the same dose of saline as the drug administration group; the mice in the nintedanib positive control group were given nintedanib (120 mg / kg); the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. After 14 days of continuous administration, the mice were observed every day, and the body weight and death status were recorded. After administration, blood was collected from the eyeballs to immediately detect the expression levels of NF-κB, TNF-α, IL-1 and IL-6 in the serum, and lung tissue was collected for HE staining and Ashcroft scoring. The results are shown in Tables 5-1 and 5-2.

[0081] [Table 6]

[0082] From the data in Table 5-1, it can be seen that the compounds 1-12 prepared in Example 1 have the effect of significantly reducing the levels of IL-1β, IL-6, TNF-α and NF-κB in the serum of mice with influenza B virus-induced pulmonary fibrosis, which shows that the compounds 1-12 have significant influenza B virus-induced pulmonary fibrosis resistance activity, and are more effective than hypoxanthine analog A, hypoxanthine analog B, hypoxanthine analog C and nintedanib. It can also be seen that there is no pulmonary fibrosis lesion in the lungs of mice in the compound 1-12 intervention group.

[0083] From the data in Table 5-2, it can be seen that the compounds 1 to 12 prepared in Example 1 have the effect of significantly reducing the degree of pulmonary fibrosis in influenza B virus-induced pulmonary fibrosis model mice, which indicates that the compounds 1 to 12 have a significant improving effect on influenza B virus pulmonary fibrosis, and are more effective than hypoxanthine analogue A, hypoxanthine analogue B, hypoxanthine analogue C and nintedanib tablets.

[0084] Example 6 This example is used to detect the anti-coronavirus-induced pulmonary fibrosis activity of compounds 1 to 12 prepared in Example 1.

[0085] Experimental Method: An in-vivo coronavirus-induced pulmonary fibrosis model was established: C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including blank control group, model group, nintedanib positive control group, hypoxanthine analog A group, hypoxanthine analog B group, hypoxanthine analog C group, compound 1 group, compound 2 group to compound 12 group, with 9 mice per group. On day 1, the mice in the blank control group were intranasally instilled with normal saline, and the mice in the other groups were intranasally instilled with HcoV-OC43 coronavirus strain (30 μL), and all were infected. On day 2, the mice were given 5 mg / kg bleomycin via the trachea to induce pulmonary fibrosis. After the model was established for two weeks, the mice in each group were intragastrically administered with saline for 14 consecutive days to be intervened; the mice in the blank control group and the model group were intragastrically administered with the same dose of saline as the drug administration group; the mice in the nintedanib positive control group were given nintedanib (120 mg / kg); the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. After 14 days of continuous administration, the mice were observed every day, and the body weight and death status were recorded. After administration, blood was collected from the eyeballs to immediately detect the expression levels of NF-κB, TNF-α, IL-1 and IL-6 in the serum, and lung tissue was collected for HE staining and Ashcroft scoring. The results are shown in Tables 6-1 and 6-2.

[0086] [Table 7]

[0087] From Table 6-1, it can be seen that compounds 1 to 12 prepared in Example 1 significantly reduce the levels of IL-1β, IL-6, TNF-α and NF-κB in serum, which indicates that compounds 1 to 12 have significant coronavirus (HCoV-OC43)-induced pulmonary fibrosis resistance activity, and show superior effects to nintedanib, hypoxanthine analog A, hypoxanthine analog B and hypoxanthine analog C. It can also be seen that there is no pulmonary fibrosis lesion in the lungs of mice in the compound 1 to 12 intervention group.

[0088] From Table 6-2, it can be seen that the compounds 1 to 12 prepared in Example 1 all have the effect of significantly reducing the degree of pulmonary fibrosis in the coronavirus-induced pulmonary fibrosis model mice, which indicates that the compounds 1 to 12 have a significant coronavirus pulmonary fibrosis resistance effect, and are superior to nintedanib, hypoxanthine analog A, hypoxanthine analog B, and hypoxanthine analog C.

[0089] Example 7 This example is used to detect the resistance activity of compounds 1 to 12 prepared in Example 1 against novel coronavirus-induced pulmonary fibrosis.

[0090] Experimental Method: An in-vivo novel coronavirus-induced pulmonary fibrosis model was established: C57BL / 6 mice (body weight 22-25g) were randomly and equally divided into multiple groups, including a blank control group, a model group, a nintedanib positive control group, a hypoxanthine analog A group, a hypoxanthine analog B group, a hypoxanthine analog C group, a compound 1 group, a compound 2 group to a compound 12 group, with 9 mice in each group. On day 1, the mice in the blank control group were intranasally instilled with normal saline, and the mice in the other groups were intranasally instilled with the COVID-19 novel coronavirus strain (30 μL) and were all infected. On day 2, the mice were given 5 mg / kg bleomycin via the trachea to induce pulmonary fibrosis. After the model was established for two weeks, the mice in each group were intragastrically administered with saline for 14 consecutive days to intervene; the mice in the blank control group and model group were intragastrically administered with the same dose of saline as the drug administration group; the mice in the nintedanib positive control group were given nintedanib (120 mg / kg); the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, compound 2 group to compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. After 14 days of continuous administration, the mice were observed every day, and the body weight and death status were recorded. After administration, blood was collected from the eyeballs to immediately detect the expression levels of NF-κB, TNF-α, IL-1 and IL-6 in the serum, and lung tissue was collected for HE staining and Ashcroft scoring. The results are shown in Tables 7-1 and 7-2.

[0091] [Table 8]

[0092] From Table 7-1, it can be seen that compounds 1 to 12 prepared in Example 1 significantly reduce the concentrations of IL-1β, IL-6, TNF-α and NF-κB in serum, and therefore compounds 1 to 12 have significant activity against novel coronavirus-induced pulmonary fibrosis, and show superior effects to nintedanib, hypoxanthine analog A, hypoxanthine analog B and hypoxanthine analog C. It can also be seen that there is no pulmonary fibrosis lesion in the lungs of mice in the compound 1 to 12 intervention group.

[0093] From Table 7-2, it can be seen that compounds 1 to 12 prepared in Example 1 all have the effect of significantly reducing the degree of pulmonary fibrosis in the new coronavirus-induced pulmonary fibrosis model mice, and therefore compounds 1 to 12 have a significant coronavirus pulmonary fibrosis resistance effect, and show an effect superior to that of nintedanib, hypoxanthine analog A, hypoxanthine analog B, and hypoxanthine analog C.

[0094] Example 8 In this example, compounds 1 to 12 prepared in Example 1 are used to detect the resistance activity against mycoplasma-induced pulmonary fibrosis.

[0095] Experimental Method: An in-vivo Mycoplasma-induced pulmonary fibrosis model was established: C57BL / 6 mice (body weight 22-25 g) were randomly and equally divided into multiple groups, including a blank control group, a model group, a nintedanib positive control group, a hypoxanthine analog A group, a hypoxanthine analog B group, a hypoxanthine analog C group, a compound 1 group, a compound 2 group to a compound 12 group, with 9 mice in each group. Before the model was established, the mice were anesthetized with diethyl ether. In addition, the mice in the blank control group were intranasally injected with 100 μL of normal saline, and the mice in the other groups were intranasally injected with MPFH strain solution (1 × 10 7The mice were then slowly instilled with an equal amount of 100 mL of mycoplasma (containing MPFH strain) into the nasal cavity for three consecutive days, and the MPFH strain solution was inhaled into the bronchi. After instillation of mycoplasma through the trachea, the mice were given 5 mg / kg bleomycin through the trachea to induce pulmonary fibrosis. After the model was established for two weeks, the mice in each group were intragastrically administered with saline for 14 consecutive days to intervene; the mice in the blank control group and the model group were intragastrically administered with the same dose of saline as the drug administration group; the mice in the nintedanib positive control group were given nintedanib (120 mg / kg); the mice in the hypoxanthine analog A group, the hypoxanthine analog B group and the hypoxanthine analog C group were given hypoxanthine analog A (120 mg / kg / d), hypoxanthine analog B (120 mg / kg / d) and hypoxanthine analog C (120 mg / kg / d), respectively; the mice in the compound 1 group, the compound 2 group to the compound 12 group were given compound 1 (120 mg / kg / d), compound 2 (120 mg / kg / d) to compound 12 (120 mg / kg / d) prepared in Example 1, respectively. The mice were administered once a day for 14 consecutive days of treatment. The mice were observed daily, and their weights and deaths were recorded. On the last day of administration, the mice were sacrificed; blood was taken from the eyeballs and kept at -80 degrees to detect blood routine indicators. Meanwhile, the lungs were washed with normal saline and separated to collect the washings to detect the number and class of white blood cells. The lung tissues were taken for HE staining and Ashcroft scoring for the degree of pulmonary fibrosis. The results are shown in Tables 8-1 and 8-2.

[0096] [Table 9]

[0097] From the data in Table 8-1, it can be seen that the compounds 1-12 prepared in Example 1 have the effect of significantly reducing the white blood cell, neutrophil, and lymphocyte levels in the blood of mice infected with mycoplasma, which shows that the compounds 1-12 have mycoplasma infection resistance effect and pulmonary fibrosis resistance activity, and show superior effects to hypoxanthine analog A, hypoxanthine analog B, hypoxanthine analog C, and nintedanib. It can also be seen that there is no pulmonary fibrosis lesion in the lungs of the mice in the compound 1-12 intervention group.

[0098] From the data in Table 8-2, it can be seen that compounds 1 to 12 prepared in Example 1 have the effect of significantly reducing the degree of pulmonary fibrosis in mycoplasma-induced pulmonary fibrosis model mice, which means that compounds 1 to 12 have a significant effect of improving mycoplasma-induced pulmonary fibrosis, and show superior effects to hypoxanthine analog A, hypoxanthine analog B, hypoxanthine analog C and nintedanib tablets.

[0099] The above description is merely a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications or replacements that can be easily conceived by anyone skilled in the art within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be defined only according to the appended claims.

Claims

1. 1. Use of a hypoxanthine compound in the preparation of a medicament for the treatment of pulmonary fibrosis, wherein the hypoxanthine compound has activity for treating pulmonary fibrosis, and the hypoxanthine compound has one of the following structures: 【Chemistry 1】 R 1 is optionally O, N, C, S or =O; R 2 , R 3 and R 4 is optionally H, C 1 -C 18 Alkyl, halogen substituted C 1 -C 18 Alkyl, trifluoromethyl, sulfonyl, sulfonamide, sulfinyl, amino acid group, 2-[bis[(pivaloyloxy)methoxy]phosphinyl]methoxy]ethyl, C 1 -C 18 fatty acid group, C 3 -C 12 Heterocyclyl and C 1 -C 18 fatty acid; or R 2 , R 3 and R 4 is optionally C 1 -C 18 Alkyl or a fatty acid group substituted with an oxygen atom, a sulfur atom, or a nitrogen atom; and R 3 and R 4 When is monosubstituted, it is attached to the unsubstituted position N through a double bond, and when fully substituted it has no double bond, use.

2. 2. Use of a hypoxanthine compound in the preparation of a medicament for the treatment of pulmonary fibrosis according to claim 1, wherein the hypoxanthine compound is one or more of the following compounds: 【Chemistry 2】 。

3. The use of a hypoxanthine compound in the preparation of a drug for the treatment of pulmonary fibrosis according to claim 1, wherein the drug for the treatment of pulmonary fibrosis comprises a drug having the efficacy of preventing and treating pulmonary fibrosis and its complications.

4. Use of a hypoxanthine compound in the preparation of a drug for treating pulmonary fibrosis as described in claim 1, wherein the drug for treating pulmonary fibrosis is a formulation prepared by using the hypoxanthine compound or a salt thereof as an active ingredient in combination with a pharma- ceutically acceptable excipient or auxiliary ingredient.

5. 5. Use of a hypoxanthine compound in the preparation of a drug for treating pulmonary fibrosis according to claim 4, wherein the formulation is an oral agent, an injection agent, or a nasal mucosal agent.

6. The use of a hypoxanthine compound in the preparation of a medicament for the treatment of pulmonary fibrosis according to claim 1, wherein the pulmonary fibrosis includes one or more of primary pulmonary fibrosis, secondary pulmonary fibrosis, idiopathic pulmonary fibrosis, pulmonary interstitial fibrosis and interstitial pneumonia.

7. The use of a hypoxanthine compound in the preparation of a medicament for the treatment of pulmonary fibrosis according to claim 6, wherein the pulmonary fibrosis includes one or more of bacterial pulmonary fibrosis, viral pulmonary fibrosis, mycoplasmal pulmonary fibrosis, chlamydial pulmonary fibrosis, immune pulmonary fibrosis and fungal pulmonary fibrosis.

8. The use of a hypoxanthine compound in the preparation of a medicament for treating pulmonary fibrosis according to claim 7, wherein the pulmonary fibrosis includes one or more of Streptococcus pneumoniae-induced pulmonary fibrosis, influenza A virus-induced pulmonary fibrosis, influenza B virus-induced pulmonary fibrosis, coronavirus-induced pulmonary fibrosis, and novel coronavirus-induced pulmonary fibrosis.

9. 9. The use of a hypoxanthine compound in the preparation of a medicament for treating pulmonary fibrosis according to claim 8, wherein the pulmonary fibrosis further comprises one or more of Klebsiella pneumoniae-induced pulmonary fibrosis, Streptococcus pneumoniae-induced pulmonary fibrosis, vancomycin-resistant Enterococcus-induced pulmonary fibrosis, drug-resistant Staphylococcus aureus-induced pulmonary fibrosis, and Acinetobacter baumannii-induced pulmonary fibrosis.

10. A compound having the structure: 【Chemistry 3】 R 1 is optionally O, N, C, S or =O; R 2 , R 3 and R 4 is optionally H, C 1 -C 18 Alkyl, halogen substituted C 1 -C 18 Alkyl, trifluoromethyl, sulfonyl, sulfonamide, sulfinyl, amino acid group, 2-[bis[(pivaloyloxy)methoxy]phosphinyl]methoxy]ethyl, C 1 -C 18 fatty acid group, C 3 -C 12 Heterocyclyl and C 1 -C 18 fatty acid; or R 2 , R 3 and R 4 is optionally C 1 -C 18 Alkyl or a fatty acid group substituted with an oxygen atom, a sulfur atom, or a nitrogen atom; and R 3 and R 4 When is monosubstituted, it is attached to the unsubstituted position N through a double bond and when fully substituted it has no double bond.

11. The compound of claim 10, which is a compound selected from the group consisting of: 【Chemistry 4】 。

12. 12. A pharmaceutical composition comprising a compound according to claim 10 or 11 or a pharma- ceutically acceptable salt thereof.

13. 13. The pharmaceutical composition of claim 12, further comprising a pharma- ceutically acceptable excipient or auxiliary ingredient.

14. The pharmaceutical composition according to claim 12 or 13, which is an oral agent, an injection agent, or an agent for nasal mucosal administration.

15. A method for treating pulmonary fibrosis, comprising administering to a subject in need thereof an effective amount of a compound according to claim 10 or 11, or a pharma- ceutically acceptable salt thereof, or a pharmaceutical composition according to any one of claims 12 to 14.

16. 16. The method of claim 15, wherein the pulmonary fibrosis comprises one or more of primary pulmonary fibrosis, secondary pulmonary fibrosis, idiopathic pulmonary fibrosis, pulmonary interstitial fibrosis, and interstitial pneumonia.

17. 16. The method of claim 15, wherein the pulmonary fibrosis comprises one or more of bacterial pulmonary fibrosis, viral pulmonary fibrosis, mycoplasmal pulmonary fibrosis, chlamydial pulmonary fibrosis, immune pulmonary fibrosis and fungal pulmonary fibrosis.

18. 16. The method of claim 15, wherein the pulmonary fibrosis comprises one or more of Streptococcus pneumoniae-induced pulmonary fibrosis, influenza A virus-induced pulmonary fibrosis, influenza B virus-induced pulmonary fibrosis, coronavirus-induced pulmonary fibrosis, and novel coronavirus-induced pulmonary fibrosis.

19. 16. The method of claim 15, wherein the pulmonary fibrosis comprises one or more of pulmonary fibrosis caused by Klebsiella pneumoniae-induced pulmonary fibrosis, Streptococcus pneumoniae-induced pulmonary fibrosis, vancomycin-resistant Enterococcus-induced pulmonary fibrosis, drug-resistant Staphylococcus aureus-induced pulmonary fibrosis, and Acinetobacter baumannii-induced pulmonary fibrosis.

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