Pyruvate-based respiratory system drug synergist and preparation method and application thereof

Abstract

The present invention relates to the field of biomedicine, and in particular to a respiratory drug synergist based on pyruvate, and its preparation method and application. The synergist is a modified betulin derivative, and the preparation steps are as follows: betulin and triphenylphosphine are added to a solvent, stirred, and ammonia water is added to react to obtain amination betulin; (7-chloroimidazo [1,2-A] pyridine-2-) methanol and phosphorus oxychloride are added to a solvent, heated for reaction, and after the reaction is completed, the reaction solution is post-treated to obtain intermediate 1; amination betulin, intermediate 1, and magnesium sulfate are added to a solvent for reaction, and the reaction solution after the reaction is post-treated to obtain intermediate 2; 1-cyclopropyl-1,3-dihydroimidazo [4,5-C] pyridine-2-one, NaH and intermediate 2 are added to a solvent, stirred for reaction, and the reaction solution is post-treated to obtain. The modified betulin derivative of the present invention is used in conjunction with pyruvate to significantly enhance the therapeutic effect of pyruvate.

Description

Technical Field

[0001] The present invention relates to the field of biomedicine, and in particular to a pyruvate-based respiratory system drug enhancer and a preparation method and application thereof. Background Art

[0002] Respiratory diseases are one of the most common diseases worldwide, especially respiratory infectious diseases caused by outbreaks of airborne infectious agents such as bacteria and viruses, which are one of the major challenges facing human survival. Respiratory syncytial virus (RSV) is a single-stranded RNA virus. RSV is transmitted seasonally and is the main cause of lower respiratory tract infections worldwide. A large part of these are lower respiratory tract infections that occur within one year of birth. Therefore, RSV is the most important source of viral lower respiratory tract infections in infancy and childhood. In recent years, studies have found that adults may also be affected by RSV, especially in cases of low immunity or the presence of other chronic diseases. RSV infection mainly affects respiratory epithelial cells, causing cell damage, inflammatory response and possible cell apoptosis through a series of complex mechanisms, thereby destroying the normal structure and function of airway tissue, thereby inducing or aggravating respiratory diseases such as bronchial asthma and pneumonia, seriously affecting the quality of life of patients.

[0003] In respiratory drugs, antioxidant ingredients are often used to relieve inflammation and protect lung tissue from free radical damage. Pyruvate, represented by sodium pyruvate, is an important metabolite in the body, has antioxidant effects and plays a key role in various physiological processes. In recent years, with the in-depth study of the biological properties of pyruvate, its application in drug development has gradually received attention. Especially in the field of respiratory drugs, pyruvate has great potential in the treatment of respiratory diseases due to its unique antioxidant, anti-inflammatory and metabolic regulation effects.

[0004] However, in the treatment of respiratory system drugs, pyruvate often needs to reach a certain drug concentration to achieve the best therapeutic effect. Secondly, due to the influence of factors such as drug metabolism and distribution in the body, the biological activity of the drug will also be reduced, and the therapeutic effect is often difficult to reach the ideal level. In addition, certain side effects may occur during the treatment process, such as gastrointestinal discomfort, allergic reactions, etc.

[0005] Betulin, also known as betulin, betulin, and betulin, is a pentacyclic triterpenoid compound extracted from birch bark. Betulin has anti-inflammatory, antiviral, and anti-cancer activities. Betulin is mainly used as a pharmaceutical intermediate. As a precursor for the synthesis of betulin derivatives, betulic acid, and corresponding derivatives, betulin and its derivatives have shown great potential as biological agents in the treatment of human immunodeficiency virus (HIV) and cancer. Therefore, developing corresponding betulin derivatives based on betulin and studying their biological activities may improve the therapeutic effect of pyruvate in respiratory diseases. Summary of the invention

[0006] In order to overcome the deficiencies of the prior art, one of the objectives of the present invention is to provide a method for preparing a pyruvate-based respiratory system drug enhancer.

[0007] One of the purposes of the present invention is achieved by the following technical solution:

[0008] A method for preparing a pyruvate-based respiratory system drug enhancer, wherein the enhancer is a modified betulin derivative, and the preparation method comprises the following steps:

[0009]

[0010] (1) adding betulin and triphenylphosphine to a solvent, stirring evenly, and then adding aqueous ammonia to react. After the reaction is completed, the reaction solution is post-treated to obtain aminated betulin;

[0011] (2) Add (7-chloroimidazo[1,2-A]pyridine-2-)methanol and phosphorus oxychloride to N,N-dimethylformamide and heat to react. After the reaction is completed, post-treat the reaction solution to obtain intermediate 1;

[0012] (3) adding the aminated betulin obtained in step (1), the intermediate 1 obtained in step (2), and magnesium sulfate to a solvent for reaction. After the reaction is completed, concentrating and recrystallizing the reaction solution to obtain the intermediate 2;

[0013] (4) Add 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridin-2-one, NaH and intermediate 2 to a solvent, stir to react, and post-treat the reaction solution to obtain a modified betulin derivative.

[0014] Furthermore, the solvent in step (1) is pyridine, the molar ratio of betulin, triphenylphosphine and NH3·H2O in ammonia water is 1:(0.05-0.2):(2-4), and the reaction time is 4-6 hours.

[0015] Furthermore, in step (2), the molar ratio of (7-chloroimidazo[1,2-A]pyridine-2-)methanol to phosphorus oxychloride is 1:(3-5), the amount ratio of (7-chloroimidazo[1,2-A]pyridine-2-)methanol to N,N-dimethylformamide is 1 g:(10-15) mL; the temperature of the heating reaction is 70-90° C., and the heating reaction time is 12-16 h.

[0016] Furthermore, the post-treatment process of step (2) is: adding water to the reaction solution for quenching, adjusting the pH value of the reaction solution to 7, extracting the reaction solution with an organic solvent, collecting the organic phase, concentrating it, and then separating it by column chromatography.

[0017] Furthermore, the solvent in step (3) is dichloromethane, the molar ratio of the amination betulin, the intermediate 1, and magnesium sulfate is 1:(2-4):(0.02-0.2), and the reaction time is 6-18 hours.

[0018] Furthermore, in step (4), the solvent is N,N-dimethylformamide, the molar ratio of the intermediate 2, 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridine-2-one, and NaH is 1:(2-4):(3-5), and the stirring reaction time is 45-60 min.

[0019] The second object of the present invention is to provide a pyruvate-based respiratory drug synergist, which can be used in combination with conventional respiratory drug pyruvate to significantly improve drug efficacy and reduce dosage and toxic reactions. The second object of the present invention is achieved by the following technical solution:

[0020] The pyruvate-based respiratory system drug enhancer is prepared by the above preparation method.

[0021] The third object of the present invention is to provide the use of a pyruvate-based respiratory drug enhancer in the preparation of a drug for treating respiratory diseases caused by respiratory syncytial virus infection, wherein the drug is in the form of an aerosol inhaler.

[0022] Furthermore, the nebulizer inhalation agent is composed of the following ingredients by mass percentage: modified betulin derivative: 0.05-0.1%, pyruvate: 0.05-0.1%, ethanol: 0.3-0.6%, potassium dihydrogen phosphate: 0.2-2%, disodium hydrogen phosphate: 0.2-2%, sodium chloride: 0.7-0.9%, and the balance is water for injection.

[0023] Furthermore, the pyruvate is sodium pyruvate.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The pyruvate-based respiratory drug synergist provided by the present invention is a modified betulin derivative. First, betulin is aminated to introduce an amino group into its structure. Using (7-chloroimidazo[1,2-A]pyridine-2-)methanol as a raw material, an aldehyde group is introduced into its structure under the action of phosphorus oxychloride, and then a Schiff base reaction is carried out with the aminated betulin to obtain intermediate 2. Finally, 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridine-2-one is used to replace the chlorine on intermediate 2 to obtain a modified betulin derivative. The synergist is used in combination with pyruvate to reduce the dosage of pyruvate, improve the therapeutic effect of pyruvate, and reduce side effects.

[0026] 2. The preparation method of the pyruvate-based respiratory system drug enhancer provided by the present invention is simple, efficient and has a simple process.

[0027] 3. The present invention has proved through a large number of experiments that the modified betulin derivative prepared by the present invention has a killing effect on respiratory syncytial virus RSV, and the use of pyruvate in combination with pyruvate significantly enhances the therapeutic effect of pyruvate. Therefore, the pyruvate-based respiratory system drug enhancer improves the stability and bioavailability of sodium pyruvate, reduces toxic side effects, and thus enhances the overall therapeutic effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is the hydrogen nuclear magnetic resonance spectrum of the aminated betulin of the present invention;

[0029] Figure 2 is a high-resolution mass spectrum of the aminated betulin of the present invention;

[0030] Figure 3 is the hydrogen nuclear magnetic resonance spectrum of the intermediate 1 of the present invention;

[0031] Figure 4 is a high-resolution mass spectrum of the intermediate 1 of the present invention;

[0032] Figure 5 is the hydrogen nuclear magnetic resonance spectrum of intermediate 2 of the present invention;

[0033] Figure 6 is a high-resolution mass spectrum of intermediate 2 of the present invention;

[0034] Figure 7 is the hydrogen nuclear magnetic resonance spectrum of the modified betulin derivative of the present invention;

[0035] Figure 8 is a high-resolution mass spectrum of the modified betulin derivative of the present invention;

[0036] Fig. 9The figure is a comparison of the damage of rat lung tissue caused by the aerosol inhalation obtained in Example 1 of the present invention (left) and the lung tissue of the blank control group (right). DETAILED DESCRIPTION

[0037] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0038] Example 1

[0039] The preparation method of a pyruvate-based respiratory system drug enhancer comprises the following steps:

[0040]

[0041] (1) Add 1 g of betulin (1 eq) and triphenylphosphine (0.1 eq) to 5 mL of pyridine, stir evenly, then slowly add aqueous ammonia (3 eq, concentration 25%), react at room temperature for 5 h, filter the reaction solution, extract the reaction solution with chloroform, dry the chloroform phase, concentrate, and separate by column chromatography to obtain amino betulin;

[0042] The hydrogen nuclear magnetic resonance spectrum of the above-mentioned amino betulin is as follows Figure 1 As shown in the high-resolution mass spectrum Figure 2 As shown, 1 HNMR (C 30 H 52 N2, 400MHz, DMSO- d6 )δ: 5.12(s, 1H), 4.93(s, 1H), 2.64-2.61(d, 1H),2.38-2.37(m, 2H), 2.10(m, 1H), 1.80(m, 3H), 1.75-1.26(m, 24H), 1.08-1.05(m,2H), 0.95-0.85(m, 17H); mass spectrometry analysis HRMS (ESI + ): [M+H] + Calculated to be 441.41, found to be 441.41; the above results confirmed that the obtained product was the target product.

[0043] (2) 1 g (7-chloroimidazo[1,2-A]pyridine-2-)methanol (1 eq) was added to 12 mL N,N-dimethylformamide (DMF), and then phosphorus oxychloride (4 eq) was added. The mixture was stirred evenly at room temperature, and the reaction solution was heated to 80°C and reacted for 14 h. After the reaction, the reaction solution was quenched with water, and then the reaction solution was neutralized with 1 M sodium hydroxide aqueous solution to pH = 7, and then the reaction solution was extracted with dichloromethane. The dichloromethane phase was dried, concentrated, and separated by column chromatography to obtain intermediate 1.

[0044] The hydrogen nuclear magnetic resonance spectrum of the intermediate 1 is as follows: Figure 3 As shown in the high-resolution mass spectrum Figure 4 As shown, 1 HNMR(C9H6Cl2N2O, 400MHz, DMSO- d6 )δ: 9.76(s, 1H), 8.49(d, 1H), 7.57(s, 1H), 6.71(m,1H), 4.59(s, 2H); Mass spectrometry analysis HRMS (ESI + ): [M+H] + Calculated: 228.99, found: 228.99; the above results confirm that the obtained product is the target product.

[0045] (3) 1 g of amino betulin (1 eq), intermediate 1 (3 eq), and magnesium sulfate (0.1 eq) were added to 10 mL of dichloromethane in sequence, and the mixture was reacted at room temperature for 12 h. The reaction solution was concentrated and recrystallized to obtain intermediate 2;

[0046] The nuclear magnetic resonance hydrogen spectrum of the intermediate 2 is as follows Figure 5 As shown in the high-resolution mass spectrum Figure 6 As shown, 1 HNMR (C 48 H 60 Cl4N6, 400MHz, DMSO- d6 )δ: 8.49(d, 2H), 8.29(s, 2H), 7.57(s, 2H), 6.71(d,2H), 5.12(m, 1H),4.93-4.92(m, 2H), 4.59(s, 4H), 2.10(m, 1H), 1.89-1.11 (s,25H), 1.08-1.05(s, 2H), 0.95-0.85(s, 17H); mass spectrometry analysis HRMS (ESI + ): [M+H] + Calculated to be 861.36, found to be 861.36; the above results confirmed that the obtained product was the target product.

[0047] (4) 1 g of 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridin-2-one (3 eq) was added to 10 mL of DMF, cooled to 0°C, stirred for 15 min, and then NaH (4 eq, purity 60%) was added. The mixture was stirred for 20 min, and then intermediate 2 (1 eq) was added in batches. After the addition was completed, the temperature was gradually raised to room temperature. The mixture was stirred for 55 min, and the reaction solution was quenched with water. The reaction solution was extracted with dichloromethane. The dichloromethane phase was dried, concentrated, and separated by column chromatography to obtain the modified betulin derivative.

[0048] The H NMR spectrum of the modified betulin derivative is as follows: Figure 7 As shown in the high-resolution mass spectrum Figure 8 As shown, 1 HNMR (C 66 H 76 Cl2N 12 O2, 400MHz, DMSO- d6 )δ: 8.49(d, 2H), 8.33-8.29(m, 4H), 8.02(d, 2H), 7.57(d, 2H), 7.03(d, 2H), 6.71(m, 2H), 5.12(m, 1H),4.93-4.92(m, 2H),4.37(s, 4H), 4.13(m, 2H), 2.10(s, 1H), 1.89-1.25(m, 35H), 0.95-0.85(m, 17H); mass spectrometry analysis HRMS (ESI + ): [M+H] + Calculated is 1139.56, found is 1139.56; the above results confirm that the obtained product is the target product.

[0049] This embodiment also provides a respiratory system drug synergist prepared by the above method, namely, a modified betulin derivative.

[0050] The present embodiment also provides an aerosol inhalation for treating respiratory syncytial virus infection, which is composed of the following ingredients by mass percentage: modified betulin derivative: 0.075%, pyruvate: 0.075%, ethanol (75%): 0.5%, potassium dihydrogen phosphate: 1%, disodium hydrogen phosphate: 1%, sodium chloride: 0.8%, and the balance is water for injection.

[0051] The preparation method of the above-mentioned nebulizer inhalation for treating respiratory syncytial virus infection is as follows: dissolve the modified betulin derivative in ethanol (75%) according to the formula amount, add potassium dihydrogen phosphate, disodium hydrogen phosphate, sodium chloride and sodium pyruvate, and add water for injection, compound, filter through a 0.22μm filter membrane, and add to a sterile nebulizer tank.

[0052] Example 2

[0053] The preparation method of a pyruvate-based respiratory system drug enhancer comprises the following steps:

[0054]

[0055] (1) Add 1 g of betulin (1 eq) and triphenylphosphine (0.05 eq) to 4 mL of pyridine, stir evenly, then slowly add aqueous ammonia (2 eq, concentration 25%), react at room temperature for 4 h, filter the reaction solution, extract the reaction solution with chloroform, dry and concentrate the chloroform phase, and separate by column chromatography to obtain amino betulin;

[0056] (2) 1 g (7-chloroimidazo[1,2-A]pyridine-2-)methanol (1 eq) was added to 10 mL N,N-dimethylformamide (DMF), and then phosphorus oxychloride (3 eq) was added. The mixture was stirred evenly at room temperature, and the reaction solution was heated to 70°C and reacted for 12 h. After the reaction, the reaction solution was quenched with water, and then the reaction solution was neutralized with 1 M sodium hydroxide aqueous solution to pH = 6. The reaction solution was extracted with dichloromethane, and the dichloromethane phase was dried, concentrated, and separated by column chromatography to obtain intermediate 1.

[0057] (3) 1 g of amino betulin (1 eq), intermediate 1 (2 eq), and magnesium sulfate (0.02 eq) were added to 10 mL of dichloromethane in sequence, and the mixture was reacted at room temperature for 6 h. The reaction solution was concentrated and recrystallized to obtain intermediate 2;

[0058] (4) Take 1 g of 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridin-2-one (2 eq) and add it to 10 mL of DMF. Cool to 0°C, stir for 15 min, then add NaH (3 eq, purity 60%), stir for 20 min, and then add intermediate 2 (1 eq) in batches. After the addition is completed, gradually warm to room temperature and stir to react for 45 min. The reaction solution is quenched with water and extracted with dichloromethane. The dichloromethane phase is dried, concentrated, and separated by column chromatography to obtain a modified betulin derivative.

[0059] This embodiment also provides a respiratory system drug synergist prepared by the above method, namely, a modified betulin derivative.

[0060] The present embodiment also provides an aerosol inhalation for treating respiratory syncytial virus infection, which is composed of the following ingredients by mass percentage: modified betulin derivative: 0.05%, pyruvate: 0.05%, ethanol (75%): 0.3%, potassium dihydrogen phosphate: 0.2%, disodium hydrogen phosphate: 0.2%, sodium chloride: 0.7%, and the balance is water for injection.

[0061] The preparation method of the above-mentioned nebulizer inhalation for treating respiratory syncytial virus infection is as follows: dissolve the modified betulin derivative in ethanol (75%) according to the formula amount, add potassium dihydrogen phosphate, disodium hydrogen phosphate, sodium pyruvate and sodium chloride, and add water for injection, compound, filter through a 0.22μm filter membrane, and add to a sterile nebulizer tank.

[0062] Example 3

[0063] The preparation method of a pyruvate-based respiratory system drug enhancer comprises the following steps:

[0064]

[0065] (1) Add 1 g of betulin (1 eq) and triphenylphosphine (0.2 eq) to 6 mL of pyridine, stir evenly, then slowly add aqueous ammonia (4 eq, concentration 25%), react at room temperature for 6 h, filter the reaction solution, extract the reaction solution with chloroform, dry the chloroform phase, concentrate, and separate by column chromatography to obtain amino betulin;

[0066] (2) 1 g (7-chloroimidazo[1,2-A]pyridine-2-)methanol (1 eq) was added to 15 mL N,N-dimethylformamide (DMF), and then phosphorus oxychloride (5 eq) was added. The mixture was stirred evenly at room temperature, and the reaction solution was heated to 90°C and reacted for 16 h. After the reaction, the reaction solution was quenched with water, and then the reaction solution was neutralized with 1 M sodium hydroxide aqueous solution to pH = 8. The reaction solution was extracted with dichloromethane, and the dichloromethane phase was dried, concentrated, and separated by column chromatography to obtain intermediate 1.

[0067] (3) 1 g of aminated betulin (1 eq), intermediate 1 (4 eq), and magnesium sulfate (0.2 eq) were added to 10 mL of dichloromethane in sequence, and the mixture was reacted at room temperature for 18 h. The reaction solution was concentrated and recrystallized to obtain intermediate 2;

[0068] (4) 1 g of 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridin-2-one (4 eq) was added to 10 mL of DMF, cooled to 0°C, stirred for 15 min, and then NaH (5 eq, purity 60%) was added. The mixture was stirred for 20 min, and then intermediate 2 (1 eq) was added in batches. After the addition was completed, the temperature was gradually raised to room temperature. The mixture was stirred for 60 min, and the reaction solution was quenched with water. The reaction solution was extracted with dichloromethane. The dichloromethane phase was dried, concentrated, and separated by column chromatography to obtain a modified betulin derivative.

[0069] This embodiment also provides a respiratory system drug synergist prepared by the above method, namely, a modified betulin derivative.

[0070] The present embodiment also provides an aerosol inhalation for treating respiratory syncytial virus infection, which is composed of the following ingredients by mass percentage: modified betulin derivative: 0.1%, pyruvate: 0.1%, ethanol (75%): 0.6%, potassium dihydrogen phosphate: 2%, disodium hydrogen phosphate: 2%, sodium chloride: 0.9%, and the balance is water for injection.

[0071] The preparation method of the above-mentioned nebulizer inhalation for treating respiratory syncytial virus infection is as follows: dissolve the modified betulin derivative in ethanol (75%) according to the formula amount, add potassium dihydrogen phosphate, disodium hydrogen phosphate, sodium pyruvate and sodium chloride, and add water for injection, compound, filter through a 0.22μm filter membrane, and add to a sterile nebulizer tank.

[0072] Comparative Example 1

[0073] This comparative example provides an aerosol inhalation for treating respiratory syncytial virus infection. The composition and preparation method of the aerosol inhalation are basically the same as those of Example 1, except that the modified betulin derivative is replaced by betulin.

[0074] Comparative Example 2

[0075] This comparative example provides an aerosol inhalation for treating respiratory syncytial virus infection. The composition and preparation method of the aerosol inhalation are substantially the same as those of Example 1, except that the modified betulin derivative is omitted.

[0076] Test Example 1

[0077] Stimulation test: 6-7 week old SD rats, weighing 180-220 g, were selected and adaptively raised for one week. The aerosol inhalation prepared in Example 1 was selected as the experimental group. A blank control group was set up, with 5 rats in each group. The aerosol inhalation prepared in Example 1 was loaded into a NE-C30 Omron compression inhaler, and the SD rats were fixed with a fixator. The experimental group was administered with a dose of 0.8 mg / kg (in terms of sodium pyruvate content), once in the morning and afternoon each day, for 14 consecutive days. The rats were killed 24 hours after the last administration, and the lung tissues were dissected and separated, fixed with 4% paraformaldehyde, and then stained with hematoxylin-eosin (HE) to observe the damage of the rat lung tissues. The experimental results are shown in FIG. Fig. 9 shown.

[0078] Depend on Fig. 9 It can be seen that compared with the blank control group, after the rats inhaled the nebulizer inhalation prepared in Example 1 for 14 days, no obvious irritation lesions were found in the lung tissue, which verifies the safety of the nebulizer inhalation of the present invention.

[0079] Test Example 2

[0080] 1. Grouping of mice

[0081] Balb / c mice aged 6-8 weeks, SPF grade, male, were taken, and the room was kept ventilated during feeding, the room temperature was 20±2°C, the relative humidity was 55±5%, and the mice were given free drinking water and food before the experiment. The feed was ordinary feed, and the mice were adaptively fed for 7 days. The mice were randomly divided into: Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, Comparative Example 2 group, positive control group, model group, and blank control group, with 10 mice in each group.

[0082] 2. Modeling

[0083] The mice were anesthetized by intraperitoneal injection of 50 mg / kg of Zotai, the blank control group was given 0.1 mL of DPBS, and the other groups were given 1×10 6 PFU / mL respiratory syncytial virus (RSV) A2 virus liquid 0.1mL; once a day, on the third day of the experiment, the mice were observed to have symptoms such as hair standing up, restlessness, rapid breathing, wheezing, abdominal muscle cramps, etc., indicating that the RSV infection mouse model was successfully constructed.

[0084] 3. Drug administration

[0085] After successful modeling, the aerosol inhalation agents of Examples 1 to 3 and Comparative Examples 1 to 2 were loaded into the drug delivery device. The Example 1 group aerosolized inhalation agent obtained in Example 1, and the other groups were the same, with a dosage of 0.4 mg / kg (based on the sodium pyruvate content). The positive control group aerosolized inhalation of budesonide solution 20 mg / kg; the model group and the blank control group aerosolized inhalation of the same amount of DPBS, each group aerosolized inhalation once a day, and the treatment was continued for 1 week.

[0086] 4. Mouse Weight Changes

[0087] The weight changes of mice were monitored before the experiment (day 0) and one week after the experiment. The results are shown in Table 1.

[0088] Table 1

[0089]

[0090] As can be seen from Table 1, after the inhalation of the aerosol inhalation agent of Examples 1-3, the weight of the mice did not decrease significantly, while after the inhalation of commercially available budesonide, the weight of the mice decreased. This result shows that the aerosol inhalation agent obtained in Examples 1-3 of the present invention does not produce obvious side effects.

[0091] 5. Levels of pulmonary inflammatory factors

[0092] One week later, mice were anesthetized by intraperitoneal injection of 50 mg / kg of Zotai, the trachea and lungs of mice were exposed by thoracotomy, the left main bronchus was ligated, and the bronchoalveoli were lavaged with 4°C phosphate buffer for 3 consecutive times to collect the bronchoalveolar lavage fluid (BALF) of mice. According to the instructions of the ELISA kit, the levels of interleukin-4 (IL-4), interleukin-6 (IL-6), and interleukin-10 (IL-10) in BALF were detected, and the results are shown in Table 2.

[0093] Table 2 Levels of inflammatory factors in BALF of mice in each group (n=10, ͞x±s)

[0094]

[0095] It can be seen from the experimental results in Table 2 that the modified betulin derivative added to the aerosol in combination with sodium pyruvate can significantly reduce the inflammatory symptoms caused by RSV infection.

[0096] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for preparing a pyruvate-based respiratory drug enhancer, characterized in that: The synergist is a modified betulin derivative, and the preparation method comprises the following steps: (1) adding betulin and triphenylphosphine to a solvent, stirring evenly, and then adding ammonia water to react. After the reaction is completed, the reaction solution is post-treated to obtain aminated betulin; (2) Add (7-chloroimidazo[1,2-a]pyridine-2-)methanol and phosphorus oxychloride to N,N-dimethylformamide and heat to react. After the reaction is completed, post-treat the reaction solution to obtain intermediate 1; (3) adding the aminated betulin obtained in step (1), the intermediate 1 obtained in step (2), and magnesium sulfate to a solvent for reaction, and after the reaction is completed, recrystallizing the reaction solution to obtain the intermediate 2; (4) Add 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridin-2-one, NaH and intermediate 2 to a solvent, stir to react, and post-treat the reaction solution to obtain a modified betulin derivative.

2. The method for preparing the pyruvate-based respiratory system drug synergist according to claim 1, characterized in that: The solvent in step (1) is pyridine, the molar ratio of betulin, triphenylphosphine and NH3·H2O in ammonia water is 1:(0.05-0.2):(2-4), and the reaction time is 4-6 hours.

3. The method for preparing the pyruvate-based respiratory drug enhancer according to claim 1, characterized in that: In step (2), the molar ratio of (7-chloroimidazo[1,2-A]pyridine-2-)methanol to phosphorus oxychloride is 1:(3-5), and the amount ratio of (7-chloroimidazo[1,2-A]pyridine-2-)methanol to N,N-dimethylformamide is 1 g:(10-15) mL; the temperature of the heating reaction is 70-90° C., and the heating reaction time is 12-16 h.

4. The method for preparing the pyruvate-based respiratory drug enhancer according to claim 1, characterized in that: The post-treatment process of step (2) is as follows: adding water to the reaction solution to quench it, adjusting the pH of the reaction solution to 7, extracting the reaction solution with an organic solvent, collecting the organic phase, concentrating it, and then separating it by column chromatography.

5. The method for preparing the pyruvate-based respiratory drug enhancer according to claim 1, characterized in that: The solvent in step (3) is dichloromethane, the molar ratio of the amination betulin, the intermediate 1, and magnesium sulfate is 1:(2-4):(0.02-0.2), and the reaction time is 6-18 hours.

6. The method for preparing the pyruvate-based respiratory system drug synergist according to claim 1, characterized in that: The solvent in step (4) is N,N-dimethylformamide, the molar ratio of the intermediate 2, 1-cyclopropyl-1,3-dihydroimidazo[4,5-C]pyridine-2-one, and NaH is 1:(2-4):(3-5), and the stirring reaction time is 45-60 min.

7. A pyruvate-based respiratory drug enhancer, characterized in that: The synergist is prepared by the preparation method according to any one of claims 1 to 6.

8. The use of a pyruvate-based respiratory drug enhancer according to claim 7, characterized in that: The invention is used in the preparation of a medicine for treating respiratory diseases caused by respiratory syncytial virus infection, wherein the dosage form of the medicine is an aerosol inhalation agent.

9. The use of the pyruvate-based respiratory system drug synergist according to claim 8, characterized in that: The aerosol inhalation preparation comprises the following components by mass percentage: Composition: modified betulin derivative: 0.05-0.1%, pyruvate: 0.05-0.1%, ethanol: 0.3-0.6%, potassium dihydrogen phosphate: 0.2-2%, disodium hydrogen phosphate: 0.2-2%, sodium chloride: 0.7-0.9%, and the balance is water for injection.

10. The use of the pyruvate-based respiratory system drug synergist according to claim 9, characterized in that: The pyruvate is sodium pyruvate.

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