GS-441524 prodrug and its pharmaceutical uses

Abstract

This invention discloses a prodrug of GS-441524 and its pharmaceutical uses. This invention provides a novel prodrug derivative of GS-441524, the structural formula of which is shown in Formula (I). Compared with the prior art, the GS-441524 prodrug derivative of this invention has ideal in vitro and in vivo pharmacokinetic properties; good stability in the gastrointestinal tract; ideal exposure of GS-441524 in plasma and lung tissue; and excellent levels of its triphosphate active metabolite in lung tissue.

Description

Technical Field

[0001] This invention belongs to the field of biomedicine and relates to prodrugs of GS-441524 and their pharmaceutical uses. Specifically, it relates to a class of prodrugs of GS-441524, and also to the pharmaceutical use of such compounds as anti-coronavirus drugs. Background Technology

[0002] The need to develop novel broad-spectrum antiviral drugs against coronaviruses (such as SARS-CoV-1, MERS-CoV, and SARS-CoV-2) is urgent. Nucleoside analogues are a hot topic in broad-spectrum anti-coronavirus drug development. These drugs are converted into nucleoside triphosphates in vivo and act on a relatively conserved target of coronaviruses—RNA-dependent RNA polymerase (RdRp)—producing a direct antiviral effect by blocking genetic material replication. The RdRp of the four different coronavirus species share the same catalytic mechanism, and their active sites contain similar key conserved amino acids. Therefore, nucleoside analogues have the potential to be developed into broad-spectrum anti-coronavirus drugs with a high resistance barrier; using these drugs as a core component of antiviral therapy is a future need in drug development and clinical treatment.

[0003] Among nucleoside analogue anticoronavirus drugs globally, Remdesivir was the first to be approved for the treatment of lung lesions caused by COVID-19 infection and has a clear broad-spectrum anticoronavirus activity; however, it requires daily intravenous injection of 100 mg for a course of treatment typically lasting 5 to 10 days, which significantly reduces medication adherence. Monupivir was approved for marketing in the UK on November 4, 2021, and was the first oral treatment for COVID-19. This drug requires a higher dosage, needing to be taken twice a day at 800 mg each time. Furthermore, whether this drug has mutagenic or reproductive toxicity still needs further investigation. Azvudine has dual activity against HIV and coronaviruses and is currently approved for marketing in my country. In addition, AT-527 is in Phase 2 clinical trials, but the latest research data indicates that this molecule failed to meet the expected primary endpoint.

[0004] Remdesivir is largely converted to nucleoside GS-441524 in plasma. This metabolite, after being distributed to lung tissue, is converted to the triphosphate active metabolite GS-441524-TP to exert its therapeutic effect. Notably, multiple reports have confirmed that direct oral administration of GS-441524 can also achieve satisfactory antiviral effects. The domestically developed drug VV116 is a prodrug of a deuterated derivative of GS-441524, while ATV006 is a 5'-hydroxyisobutyrylated prodrug of GS-441524; both exhibit broad-spectrum in vitro anticoronavirus activity. Therefore, the design and development of novel prodrugs are key to endowing nucleoside GS-441524 with novel drug-like properties and therapeutic effects. Summary of the Invention

[0005] To address the problems existing in the prior art, the first objective of this invention is to provide a novel prodrug derivative of GS-441524.

[0006] A second object of the present invention is to provide pharmaceutical uses for the aforementioned GS-441524 prodrug derivative.

[0007] To achieve the above objectives, the technical solution adopted by the present invention to solve its technical problem is as follows:

[0008] In a first aspect, the present invention provides a novel prodrug derivative of GS-441524, the structural formula of which is shown in formula (I):

[0009]

[0010] Among them, R 1 Selected from: H, C 1-6 alkyl, benzyl or n is selected from: 0, 1, 2, or 3; m is selected from: 0, 1, 2, or 3; W is selected from: R 2 Selected from: H, C 2-7 Acyl or C 3-6 Cycloalkylformyl; R 3 Selected from: H or C 1-3 Alkyl; R 4 Selected from: H or C 1-3 alkyl.

[0011] Furthermore,

[0012] R 1 Selected from: H, C 1-6 Alkyl, benzyl, n is selected from: 0 or 1; m is selected from: 0 or 1; W is selected from: R 2 Selected from: H, acetyl, propionyl, n-butyryl, isobutyryl, cyclopropylformyl, or cyclobutylformyl; R 3 Selected from: H or methyl; R 4 Selected from: H or methyl.

[0013] Furthermore,

[0014] R 1 Selected from: H, benzyl, n is selected from: 0 or 1; m is selected from: 0 or 1; W is selected from: R 2 Selected from: H, isobutyryl, or cyclobutylformyl; R 3 Selected from: H or methyl; R 4 Selected from: H or methyl.

[0015] Furthermore,

[0016] The compound of formula (I) is any one of compounds 1 to 24 having the following structures, or a combination thereof:

[0017]

[0018]

[0019] Most preferably, the compound of formula (I) is selected from the group consisting of I-4, I-5, I-7, I-8, I-10, I-11, I-12, I-13, I-15, I-16, I-17, I-19, I-21, I-23, and I-24.

[0020] Secondly, the present invention also protects a pharmaceutical composition comprising the GS-441524 derivative described above or a pharmaceutically acceptable salt, tautomer, meso compound, racemic compound, stereoisomer or solvate thereof, and a pharmaceutically acceptable carrier.

[0021] Thirdly, the present invention also protects the use of the GS-441524 derivatives described above or pharmaceutically acceptable salts, tautomers, mesosomes, racemates, stereoisomers or solvates or the compositions described above in the preparation of anticoronavirus drugs.

[0022] The coronaviruses mentioned are selected from: Severe acute respiratory syndrome coronavirus (SARS-CoV), 2019 novel coronavirus (SARS-CoV-2), Middle East respiratory syndrome coronavirus (MERS-CoV), human coronavirus OC43, human coronavirus 229E, human coronavirus NL63, and human coronavirus HKUl.

[0023] definition

[0024] Unless otherwise stated, the following terms as used in this application shall have the following meanings. A particular term should not be considered uncertain or unclear unless specifically defined, but should be understood in accordance with its ordinary meaning in the art. When a trade name appears herein, it is intended to refer to the corresponding product or its active ingredient.

[0025] C in this article 1-3This means that the part has 1 to 3 carbon atoms within a given range. Specifically, the group can have 1, 2, or 3 carbon atoms.

[0026] The term "alkyl" refers to a compound with the general formula C10. n H 2n+1 The alkyl group. This alkyl group can be straight-chain or branched. For example, the term "C 1-3 "Alkyl" refers to an alkyl group containing 1 to 3 carbon atoms (e.g., methyl, ethyl, n-propyl, isopropyl).

[0027] The term "pharmaceutical acceptable" refers to compounds, materials, compositions, and / or dosage forms that, within the bounds of reliable medical judgment, are suitable for use in contact with human and animal tissues without excessive toxicity, irritation, allergic reactions, or other problems or complications, in proportion to a reasonable benefit / risk ratio.

[0028] As pharmaceutically acceptable salts, for example, metal salts, ammonium salts, salts formed with organic bases, salts formed with inorganic acids, salts formed with organic acids, and salts formed with basic or acidic amino acids may be mentioned.

[0029] The term "pharmaceutical composition" refers to a mixture of one or more compounds of this application or their salts with pharmaceutically acceptable excipients. The purpose of a pharmaceutical composition is to facilitate the administration of the compounds of this application to an organism.

[0030] The term "pharmaceuticalally acceptable excipient" refers to excipients that do not cause significant irritation to the organism and do not impair the biological activity and properties of the active compound. Suitable excipients are well known to those skilled in the art, such as carbohydrates, waxes, water-soluble and / or water-swellable polymers, hydrophilic or hydrophobic materials, gelatin, oils, solvents, water, etc.

[0031] This application also includes compounds of this application that are identical to those described herein, but with one or more atoms replaced by isotopes of atomic weights or mass numbers different from those commonly found in nature. Examples of isotopes that can be incorporated into compounds of this application include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine, iodine, and chlorine, such as 2H, 3H, 11C, 13C, 14C, 13N, 15N, 15O, 17O, 18O, 31P, 32P, 35S, 18F, 123I, 125I, and 36Cl, respectively.

[0032] The pharmaceutical compositions of this application can be prepared by combining the compounds of this application with suitable pharmaceutically acceptable excipients, for example, in solid, semi-solid, liquid or gaseous formulations, such as tablets, pills, capsules, powders, granules, ointments, emulsions, suspensions, suppositories, injections, inhalers, gels, microspheres and aerosols.

[0033] Typical routes of administration for the compounds of this application or their pharmaceutically acceptable salts or pharmaceutical compositions thereof include, but are not limited to, oral, rectal, topical, inhalation, parenteral, sublingual, vaginal, intranasal, intraocular, intraperitoneal, intramuscular, subcutaneous, and intravenous administration.

[0034] The pharmaceutical composition of this application can be manufactured using methods well known in the art, such as conventional mixing, dissolving, granulation, sugar-coated pill making, grinding, emulsification, freeze drying, etc.

[0035] In some embodiments, the pharmaceutical composition is in oral form. For oral administration, the pharmaceutical composition can be formulated by mixing the active compound with pharmaceutically acceptable excipients well known in the art. These excipients enable the compounds of this application to be formulated into tablets, pills, lozenges, sugar-coated tablets, capsules, liquids, gels, pastes, suspensions, etc., for oral administration to patients.

[0036] Solid oral compositions can be prepared using conventional mixing, filling, or tableting methods. For example, they can be obtained by mixing the active compound with solid excipients, optionally milling the resulting mixture, adding other suitable excipients if necessary, and then processing the mixture into granules to obtain the core of a tablet or sugar-coated formulation. Suitable excipients include, but are not limited to, binders, diluents, disintegrants, lubricants, glidants, sweeteners, or flavoring agents.

[0037] The pharmaceutical composition may also be suitable for parenteral administration, such as in suitable unit dosage forms of sterile solutions, suspensions or lyophilized products.

[0038] The compounds of this application can be prepared by a variety of synthetic methods known to those skilled in the art, including the specific embodiments listed below, embodiments formed by combining them with other chemical synthetic methods, and equivalent substitutions known to those skilled in the art. Preferred embodiments include, but are not limited to, the embodiments of this application.

[0039] The chemical reactions in the specific embodiments of this application are carried out in a suitable solvent, which must be suitable for the chemical changes and the reagents and materials required in this application. In order to obtain the compounds of this application, it is sometimes necessary for those skilled in the art to modify or select the synthesis steps or reaction process based on existing embodiments.

[0040] Beneficial effects

[0041] Compared with the prior art, the GS-441524 prodrug derivative of the present invention has ideal in vitro and in vivo pharmacokinetic properties; it has good stability in the gastrointestinal tract and ideal exposure of GS-441524 in plasma and lung tissue; and it has excellent levels of triphosphate active metabolites in lung tissue. Attached Figure Description

[0042] Figure 1 The 1H NMR spectrum of compound I-4.

[0043] Figure 2 The 1H NMR spectrum of compound I-12.

[0044] Figure 3 The results are from an in vitro metabolism study of compound I-4.

[0045] Figure 4 The results are from an in vitro metabolism study of compound I-12.

[0046] Figure 5 The results are from in vivo metabolism studies of compounds I-4 and I-5.

[0047] Figure 6 This represents the exposure level of RTP, a representative active metabolite in the lungs. Detailed Implementation

[0048] The following embodiments illustrate the content of the present invention. In this invention, the embodiments described below are for better explanation and are not intended to limit the scope of the invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope.

[0049] Example 1: Synthesis of Compound I-1

[0050]

[0051] Synthesis of Compound II. GS-441524 (4370 mg, 15 mmol) was placed in a double-necked flask under argon protection. 70 mL of acetone was added to dissolve the compound, followed by the addition of 2,2-dimethoxypropane (9.1 mL, 72 mmol). The mixture was stirred at room temperature. Concentrated sulfuric acid (1083 μL, 19.5 mmol) was slowly added dropwise. The reaction was continued at room temperature for 30 min, then heated to 45 °C for another 30 min. After the reaction was confirmed to be complete by TLC, the reaction solution was cooled to room temperature, and solid sodium bicarbonate (2.9 g) and water (2.9 mL) were added. The mixture was stirred for another 15 min. The reaction solution was concentrated under vacuum. The crude product was extracted with ethyl acetate, washed with saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was then subjected to silica gel column chromatography (DCM / MeOH = 15:1) to obtain a white, foamy intermediate (4.9 g, 98.6%). The intermediate (2900 mg, 8.76 mmol) was placed in a two-necked flask under argon protection, dissolved in 6 mL of acetonitrile, and then N,N-dimethylformamide methyl acetal (1272 μL, 10.51 mmol) was added dropwise. The mixture was reacted at room temperature for 2 h. After the reaction was completed by TLC monitoring, the reaction solution was concentrated under vacuum. The crude product was slurried with anhydrous diethyl ether, filtered, and dried to give a white solid II (3.09 g, 93.6%). 1 H NMR(300MHz,Chloroform-d)δ8.90(s,1H),8.03(s,1H),7.13(d,J=4.6Hz,1H),6.95(d,J=4.6Hz,1H),5.45(d,J=6.6Hz,1H),5.26(dd, J=6.6,2.4Hz,1H),4.80–4.55(m,2H),4.02(d,J=12.3Hz,1H),3.86(t,J=11.9Hz,1H),3.28(d,J=5.9Hz,6H),1.83(s,3H),1.41(s,3H).

[0052] Synthesis of Compound III. Compound II (386 mg, 1 mmol), benzyl succinate (312 mg, 1.5 mmol), EDCI (288 mg, 1.5 mmol), and DMAP (183 mg, 1.5 mmol) were placed in a sealed tube, and 5 mL of dichloromethane was added. The mixture was heated at 60 °C for 3 h. After the reaction was completed by TLC, the reaction solution was cooled to room temperature, and a saturated aqueous sodium carbonate solution was added. The reaction solution was extracted with DCM, washed with saturated aqueous sodium carbonate solution and saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was subjected to silica gel column chromatography (DCM / MeOH = 30:1) to give oil III (547 mg, 95%). 1H NMR(300MHz,Chloroform-d)δ8.85(s,1H),8.11(s,1H),7.45–7.27(m,5H),7.03(dd,J =4.6,1.2Hz,1H),6.90(dd,J=4.6,1.3Hz,1H),5.53(d,J=6.7Hz,1H),5.13(s,2H),4.93 (dd,J=6.9,4.2Hz,1H),4.67–4.56(m,1H),4.44(dd,J=12.0,4.3Hz,1H),4.31(dd,J=11 .8,5.6Hz,1H),3.24(d,J=8.2Hz,6H),2.67(d,J=4.0Hz,4H),1.78(s,3H),1.43(s,3H).

[0053] Synthesis of Compound I-1. Compound III (576 mg, 1 mmol) was placed in a single-necked flask, dissolved in 6.2 mL of anhydrous ethanol, and then glacial acetic acid (1145 μL, 20 mmol) was added. The mixture was heated overnight at 50 °C. After the reaction was completed as monitored by TLC, the reaction solution was concentrated under vacuum, and 2.5 mL of 90% trifluoroacetic acid was added. The mixture was reacted at room temperature for 2 h. After the reaction was completed as monitored by TLC, the pH was adjusted to 8 by adding saturated sodium bicarbonate aqueous solution to the reaction flask. The reaction solution was extracted with ethyl acetate, washed with saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was subjected to silica gel column chromatography (DCM / MeOH = 15:1) and slurryed with n-hexane to give a white solid compound I-1 (400 mg, 83.1%). 1 H NMR(300MHz,Methanol-d4)δ7.88(s,1H),7.32(s,5H),6.90(s,2H),5.10(s,2H ),4.88(d,J=5.4Hz,1H),4.49–4.24(m,3H),4.15(t,J=5.7Hz,1H),2.65(s,4H). 13 C NMR(126MHz,Methanol-d4)δ172.39,172.31,155.87,136.05,128.13,127.78,127.7 4,124.19,116.61,116.28,110.89,82.09,80.15,74.16,70.68,66.11,28.59,28.53.

[0054] Example 2 Synthesis of Compound I-2

[0055]

[0056] Following the method described in Example 1, using compound II (386 mg, 1 mmol) as the starting material, monobenzyl succinate was replaced with monoisopropyl succinate. After a two-step reaction, a white solid I-2 (104 mg, two-step yield 74%) was finally obtained. 1 H NMR (300MHz, Methanol-d4) δ7.88(s,1H),6.91(s,2H),4.96(q,J=6.3Hz,1H),4.90(d,J=5.4Hz ,1H),4.51–4.26(m,3H),4.16(t,J=5.6Hz,1H),2.57–2.62(m,4H),1.20(dd,J=6.3,2.2Hz,6H). 13 C NMR (126MHz, Methanol-d4) δ172.40,172.18,155.87,146.94,124.22,116.60,116. 27,110.90,101.17,82.10,80.18,74.16,70.69,68.08,63.30,28.91,28.55,20.62.

[0057] Example 3 Synthesis of Compound I-3

[0058]

[0059] Following the method described in Example 1, using compound II (386 mg, 1 mmol) as the starting material, monobenzyl succinate was replaced with monomethyl succinate, and after a two-step reaction, a white solid I-3 (166 mg, two-step yield 76%) was finally obtained. 1 H NMR (300MHz, Methanol-d4) δ7.88 (s, 1H), 6.91 (s, 2H), 4.89 (d, J = 5.3Hz, 1H), 4.52–4.27(m,3H),4.16(t,J=5.6Hz,1H),3.66(s,3H),2.61(d,J=2.8Hz,4H). 13 C NMR(126MHz,Methanol-d4)δ173.12,172.31,155.89,146.94,124.22,116.5 9,116.25,110.84,82.07,80.15,74.17,70.70,63.24,50.90,28.49,28.27.

[0060] Example 4 Synthesis of Compound I-4

[0061]

[0062] Compound II (348 mg, 0.9 mmol), succinic anhydride (50 mg, 0.5 mmol), and DMAP (91 mg, 0.75 mmol) were placed in a double-necked flask under argon protection. 5 mL of DCM was added to dissolve the compound, followed by the dropwise addition of triethylamine (140 μL, 1.0 mmol). The reaction was carried out at room temperature for 2 h. After the reaction was monitored by TLC until complete, the reaction solution was transferred to a sealed tube, and EDCI (144 mg, 0.75 mmol) was added. The reaction was then carried out at 60 °C for 2 h. The reaction was monitored by TLC until complete. The reaction solution was extracted with DCM, washed with saturated sodium carbonate solution and saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was subjected to silica gel column chromatography (DCM / MeOH = 30:1) to give a white solid (337 mg, 79%). A portion of this solid (285 mg, 0.33 mmol) was used for further deprotection: 2 mL of anhydrous ethanol was added to dissolve the solid in a single-necked flask, followed by the addition of glacial acetic acid (377 μL, 20 mmol), and the mixture was heated overnight at 50 °C. After the reaction was monitored by TLC until complete, the reaction solution was concentrated under vacuum, and 2 mL of 90% trifluoroacetic acid was added. The mixture was then reacted at room temperature for 2 h. After the reaction was monitored by TLC to be complete, a saturated sodium bicarbonate aqueous solution was added to the reaction flask to adjust the pH to 8. The reaction solution was extracted with ethyl acetate, washed with saturated brine, dried with anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was subjected to silica gel column chromatography (DCM / MeOH = 10:1) and slurryed with n-hexane to obtain a white solid I-4 (180 mg, 82.2%). 1 H NMR (300MHz, Methanol-d4) δ7.87(s,2H),6.90(s,4H),4.91(d,J=5.3Hz,2H),4.51–4.25(m,6H),4.18(t,J=5.5Hz,2H),2.60(s,4H). 13 C NMR (126MHz, Methanol-d4) δ172.24,155.85,146.93,124.12,116.59,116.32,110.88,101.23,82.18,80.04,74.17,70.69,63.19,28.42.

[0063] Example 5: Synthesis of Compound I-5

[0064]

[0065] Compound I-1 (165 mg, 0.34 mmol) and palladium on carbon (33 mg, 20% w / w) were placed in a two-necked flask, purged three times with hydrogen, dissolved in 3 mL of anhydrous ethanol, and reacted at room temperature for 2 h. After the reaction was completed as monitored by TLC, the mixture was filtered through diatomaceous earth, and the filtrate was concentrated under vacuum. The resulting product was slurried with n-hexane to give a white solid I-5 (130 mg, 97%).1 H NMR (300MHz, Methanol-d4) δ7.88 (s, 1H), 6.91 (s, 2H), 4.90 (s, 1H), 4.52–4.25 (m, 3H), 4.17 (t, J = 5.6Hz, 1H), 2.59 (s, 4H). 13 CNMR(126MHz,Methanol-d4)δ174.87,172.59,155.87,146.88,124.25,116.5 7,116.25,110.84,101.19,82.11,80.07,74.20,70.67,63.10,28.70,28.58.

[0066] Example 6 Synthesis of Compound I-6

[0067]

[0068] Following the method described in Example 1, using compound II as the raw material, monobenzyl succinate was replaced with monobenzyl glutarate, and after a three-step reaction, white solid I-6 was finally obtained. 1 H NMR(300MHz,Methanol-d4)δ7.87(s,1H),7.46–7.19(m,5H),6.89(s,2H),5.09(s,2 H),4.51–4.25(m,3H),4.15(t,J=5.7Hz,1H),2.49–2.27(m,4H),1.98–1.80(p,2H). 13 C NMR(126MHz,Methanol-d4)δ173.07,172.90,155.86,146.95,136.20,128.13,127.76,127.74,1 16.59,116.27,110.80,101.18,82.07,80.13,74.25,70.73,65.87,63.01,32.62,32.50,19.84.

[0069] Example 7 Synthesis of Compound I-7

[0070]

[0071] Following the method of Example 4, using compound II as the raw material, succinic anhydride was replaced with glutaric anhydride, and finally a white solid I-7 was obtained. 1H NMR (300MHz, Methanol-d4) δ7.87(s,2H),6.88(s,4H),4.88(s,2H),4.50–4.25(m,6H),4.17(t,J=5.7Hz,2H),2.49–2.21(m,4H),1.87–1.79(m,2H). 13 C NMR (126MHz, Methanol-d4) δ172.87,155.83,146.93,124.18,116.57,116.32,110.83,101.24,82.20,80.00,70.78,62.97,32.45,19.69.

[0072] Example 8 Synthesis of Compounds I-8

[0073]

[0074] Following the method of Example 5, a white solid I-8 was prepared using compound I-6 as a raw material. 1 H NMR (300MHz, Methanol-d4) δ7.88(s,1H),6.91(s,2H),4.88(s,1H),4.54–4.27(m,3H),4.22–4.12(m,1H),2.49–2.26(m,4H),1.87(m,2H). 13 CNMR(126MHz,Methanol-d4)δ175.68,173.02,155.86,146.89,124.27,116. 56,110.79,101.22,82.10,80.04,74.26,70.75,62.95,32.73,32.63,19.95.

[0075] Example 9: Synthesis of Compounds I-9

[0076]

[0077] Following the method in Example 1, using compound II as the raw material, monobenzyl succinate was replaced with (S)-4-(benzyloxy)-2-methyl-4-oxobutyric acid, and finally a white solid I-9 was obtained. 1H NMR(300MHz, Methanol-d4)δ7.87(s,1H),7.32(s,5H),6.90(d,J=1.2Hz,2H),5.18–5.00(m,2H),4.89(s,1H),4.46–4.25(m,3H ),4.14(t,J=5.5Hz,1H),3.06–2.82(m,1H),2.71(dd,J=16.7,8.6Hz,1H),2.53(dd,J=16.7,5.5Hz,1H),1.18(d,J=7.1Hz,3H). 13 C NMR (126MHz, Methanol-d4) δ175.16,171.82,155.87,146.96,136.03,128.17,127.87,127.85,124. 21,116.63,116.33,110.98,101.21,82.05,80.14,74.19,70.68,66.12,63.38,37.07,35.83,15.90.

[0078] Example 10 Synthesis of Compound I-10

[0079]

[0080] Compound II (155 mg, 0.4 mmol), (S)-2-methylsuccinic acid (26.4 mg, 0.2 mmol), EDCI (115 mg, 0.6 mmol), and DMAP (25 mg, 0.2 mmol) were placed in a sealed tube, and 3 mL of dichloromethane was added. The mixture was heated at 60 °C for 3 h. After the reaction was completed by TLC, the reaction solution was cooled to room temperature, and a saturated sodium carbonate aqueous solution was added. The reaction solution was extracted with DCM, washed with saturated sodium carbonate aqueous solution and saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was subjected to silica gel column chromatography (DCM / MeOH = 30:1) to give a white foamy solid (165 mg, 95%). 1H NMR(300MHz,Chloroform-d)δ8.89(s,2H),8.10(s,2H),7.02(d,J=4.5Hz,2H) ,6.90(d,J=4.5Hz,2H),5.52(d,J=6.7Hz,2H),5.01–4.85(m,2H),4.70–4.51( m,2H),4.49–4.24(m,4H),3.26(d,J=3.8Hz,12H),3.02–2.86(m,1H),2.83–2. 65(m,1H),2.54–2.37(m,1H),1.78(s,6H),1.42(s,6H),1.21(d,J=7.1Hz,3H).

[0081] Following the synthesis method in Example 4, the above product was deprotected to obtain a white solid I-10 (302 mg, 78.2%). 1 HNMR(300MHz, Methanol-d4)δ7.87(s,2H),6.89(s,4H),4.90(d,J=5.3Hz,2H),4.49–4.26(m,6H),4.16(q,J=5.4,4 .7Hz,2H),2.86(q,J=7.2Hz,1H),2.65(dd,J=16.8,8.0Hz,1H),2.46(dd,J=16.6,6.0Hz,1H),1.15(d,J=7.0Hz,3H). 13 C NMR(126MHz,Methanol-d4)δ175.08,171.68,155.83,146.95,124.17,124.15,116.59,116.37,116.35,110.99,11 0.98,101.27,82.08,82.06,80.10,80.09,74.21,70.77,70.71,63.34,63.28,47.86,47.52,36.85,35.68,15.81.

[0082] Example 11 Synthesis of Compound I-11

[0083]

[0084] Following the method of Example 5, a white solid I-11 was prepared using compound I-9 as a raw material. 1H NMR (300MHz, Methanol-d4) δ7.89 (d, J = 7.0Hz, 1H), 6.92 (q, J = 4.6Hz, 2H), 4.93 (s, 1H), 4.52–4.31 (m, 3H), 4.28–4. 10(m,1H),2.89(q,J=7.2Hz,1H),2.65(dd,J=16.7,8.1Hz,1H),2.42(dd,J=16.7,6.1Hz,1H),1.18(d,J=7.1Hz,3H). 13 C NMR(126MHz,Methanol-d4)δ175.53,174.46,155.87,146.88,124.27,116.59,1 16.30,110.95,101.28,82.08,80.06,74.23,70.66,63.20,37.28,35.91,15.90.

[0085] Example 12 Synthesis of Compound I-12

[0086]

[0087] Following the method in Example 1, using compound II as the raw material, monobenzyl succinate was replaced with 4-(benzyloxy)-2,2-dimethyl-4-oxobutyric acid, and finally a white solid I-12 was obtained. 1 H NMR(300MHz, Methanol-d4)δ7.87(s,1H),7.31(s,5H),6.97–6.80(m,2H),5.04(s,2H),4.88(d,J=5.4Hz,1H), 4.37(dd,J=6.1,3.8Hz,1H),4.30(d,J=4.2Hz,2H),4.13(t,J=5.7Hz,1H),2.65(s,2H),1.22(d,J=5.3Hz,6H). 13 C NMR (126MHz, Methanol-d4) δ176.74,171.29,155.89,146.99,135.98,128.16,127.97,127.86,124. 25,116.65,116.34,110.95,82.20,80.01,74.21,70.69,66.02,63.53,43.70,40.44,24.48,24.36.

[0088] Example 13 Synthesis of Compound I-13

[0089]

[0090] Following the method of Example 5, the dicarboxylic acid was replaced with 2,2-dimethyl-4-oxobutyric acid, and finally a white solid I-13 was obtained. 1 H NMR (300MHz, Methanol-d4) δ7.87 (s, 2H), 6.89 (d, J = 1.5Hz, 4H), 4.90 (s, 2H), 4. 46–4.23(m,6H),4.22–4.08(m,2H),2.57(d,J=3.5Hz,2H),1.19(d,J=4.4Hz,6H). 13 CNMR(126MHz,Methanol-d4)δ176.70,171.16,147.00,146.95,124.22,124.15,116.61,116.39,116.36,11 0.97,110.95,82.25,82.10,79.92,74.26,74.19,70.87,70.73,63.51,63.23,43.40,40.38,24.35,24.27.

[0091] Example 14 Synthesis of Compound I-14

[0092]

[0093] Following the method of Example 5, a white solid I-14 was prepared using compound I-12 as a raw material. 1 H NMR(300MHz,Methanol-d4)δ7.88(s,1H),6.92(s,2H),4.88(s,1H),4.49–4.24 (m,3H),4.15(t,J=5.6Hz,1H),2.45(d,J=3.1Hz,2H),2.37(s,2H),1.10(s,6H). 13 C NMR(126MHz,Methanol-d4)δ177.20,173.97,155.87,146.90,124.33,116.6 0,116.35,110.91,101.31,82.31,79.84,74.31,70.66,63.31,44.09,40.28.

[0094] Example 15 Synthesis of Compound I-15

[0095]

[0096] Following the method described in Example 1, using compound II as a raw material, monobenzyl succinate was replaced with 5-(benzyloxy)-3,3-dimethyl-5-oxovalerate to finally obtain white solid I-15. 1 H NMR (300MHz, Methanol-d4) δ7.87(s,1H),7.33(s,5H),6.90(s,2H),5.07(s,2H),4.88(d,J=5.1H z,1H),4.44–4.25(m,3H),4.13(t,J=5.5Hz,1H),2.44(s,2H),2.41(d,J=3.6Hz,2H),1.06(s,6H). 13 C NMR(126MHz,Methanol-d4)δ171.80,171.60,155.88,146.94,136.22,128.12,127.95,127.77,124.24, 116.59,116.28,110.85,101.17,82.06,80.06,74.22,70.81,65.64,62.86,44.51,44.40,32.20,26.67.

[0097] Example 16 Synthesis of Compound I-16

[0098]

[0099] Following the method of Example 4, using compound II as the raw material, succinic anhydride was replaced with 3,3-dimethylglutaric anhydride, and finally a white solid I-16 was obtained. 1 H NMR (300MHz, Methanol-d4) δ7.87 (s, 2H), 6.89 (d, J = 3.6Hz, 4H), 4.89 (s, 2H), 4.46–4.22(m,6H),4.15(t,J=3.9,2.4Hz,2H),2.46–2.26(m,4H),1.02(s,6H). 13 C NMR (126MHz, Methanol-d4) δ171.64,155.84,146.95,124.23,116.58,110.92,101.31,82.13,74.29,70.87,62.85,44.41,32.15,26.64.

[0100] Example 17 Synthesis of Compound I-17

[0101]

[0102] Following the method of Example 5, a white solid I-17 was prepared using compound I-15 as a raw material. 1 H NMR(300MHz,Methanol-d4)δ7.88(s,1H),6.92(s,2H),4.88(s,1H),4.49–4.24 (m,3H),4.15(t,J=5.6Hz,1H),2.45(d,J=3.1Hz,2H),2.37(s,2H),1.10(s,6H). 13 C NMR (126MHz, Methanol-d4) δ174.45,171.82,155.87,124.29,116.31,110.89,101.29,82.09,80.00,74.27,70.84,62.83,44.85,31.91,26.61.

[0103] Example 18 Synthesis of Compound I-18

[0104]

[0105] Following the method described in Example 1, using compound II as a raw material, monobenzyl succinate was replaced with (E)-4-methoxy-4-oxo-2-enoic acid to prepare a white solid I-18 (412 mg, 83%). 1 H NMR (300MHz, Methanol-d4) δ7.87 (s, 1H), 6.89 (s, 2H), 6.78 (s, 2H), 4.94 (d, J = 5.3 Hz,1H),4.69–4.55(m,1H),4.49–4.38(m,2H),4.24(t,J=5.6Hz,1H),3.82(s,3H). 13 C NMR(126MHz,Methanol-d4)δ165.26,164.44,155.87,146.98,133.24,132.66,12 4.09,116.65,116.23,110.89,101.18,82.01,80.25,74.10,70.69,63.55,51.47.

[0106] Example 19 Synthesis of Compound I-19

[0107]

[0108] Compound I-4 (664 mg, 1 mmol), isobutyric acid (528 mg, 6 mmol), EDCI (1150 mg, 6 mmol), and DMAP (244 mg, 2 mmol) were placed in a sealed tube, and 20 mL of acetonitrile was added. The mixture was heated at 60 °C for 12 h. After the reaction was completed as monitored by TLC, the reaction solution was cooled to room temperature, and a saturated sodium carbonate aqueous solution was added. The reaction solution was extracted with DCM, washed with saturated sodium carbonate aqueous solution and saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under vacuum. The crude product was subjected to silica gel column chromatography (DCM / MeOH = 30:1) to obtain a waxy compound I-19 (490 mg, 52%). HRMS (ESI) for C 44 H 53 N 10 O 14 [M+H] + calcd945.3737,found 945.3749.

[0109] Example 20 Synthesis of Compound I-20

[0110]

[0111] Following the method of Example 19, a white solid I-20 was prepared from compound I-1. HRMS(ESI) for C 31 H 36 N5O9[M+H] + calcd 622.2508, found 622.2499.

[0112] Example 21 Synthesis of Compound I-21

[0113]

[0114] Following the method of Example 5, a white solid I-21 was prepared from compound I-20. HRMS(ESI) for C 24 H 28 N5O9[MH] - calcd 530.1893, found 530.1901.

[0115] Example 22 Synthesis of Compound I-22

[0116]

[0117] Following the method of Example 19, a white solid I-22 was prepared from compound I-7. HRMS(ESI) for C 37 H 39 N 10 O14 [M+H] + calcd 847.2642,found 847.2649.

[0118] Example 23 Synthesis of compound I-23

[0119]

[0120] Following the method of Example 19, a white solid I-23 was prepared from compound I-6. HRMS(ESI) for C 34 H 38 N5O9[M+H] + calcd 660.2664, found 660.2673.

[0121] Example 24 Synthesis of Compound I-24

[0122]

[0123] Following the method of Example 5, a white solid, I-24, was prepared from compound I-23. HRMS(ESI) for C 27 H 30 N5O9[MH] - calcd 568.2049,found 568.2057.

[0124] Example 25 In vitro stability of the compound

[0125] I. HPLC Method

[0126] The chromatographic column used was a Waters XSelect HSS T3 (4.6 × 150 mm, 3.5 μm). The mobile phase consisted of water containing 0.1% formic acid (v / v) (A) and acetonitrile (B). The column temperature was 40 °C, the flow rate was 1 mL / min, and the injection volume was 5 μL. The UV detection wavelength was 254 nm.

[0127] The gradient elution program ① is as follows: 0–2.8 min, 1% B; 2.8–3 min, 1–12% B; 3–5.5 min, 12% B; 5.5–5.7 min, 12–25% B; 5.7–8 min, 25% B; 8–8.2 min, 25–46% B; 8.2–13 min, 46% B; 13–13.1 min, 46% B; 13.1–16 min, 1% B.

[0128] The gradient elution program ② is as follows: 0–2.8 min, 1% B; 2.8–3 min, 1–12% B; 3–5.5 min, 12% B; 5.5–5.7 min, 12–20% B; 5.7–8 min, 20% B; 8–8.2 min, 20–46% B; 8.2–13 min, 46% B; 13–13.1 min, 46–1% B; 13.1–16 min, 1% B.

[0129] The gradient elution program ③ is as follows: 0–2.8 min, 1% B; 2.8–3 min, 1–18% B; 3–8 min, 18% B; 8–8.2 min, 18–46% B; 8.2–13 min, 46% B; 13–13.1 min, 46% B; 13.1–16 min, 1% B.

[0130] The gradient elution program ④ is as follows: 0–2.8 min, 1% B; 2.8–3 min, 1–13% B; 3–6 min, 13% B; 6–6.5 min, 13–32% B; 6.5–8.5 min, 32% B; 8.5–9 min, 32–52% B; 9–13 min, 52% B; 13–13.1 min, 52–1% B; 13.1–16 min, 1% B.

[0131] The gradient elution program ⑤ is as follows: 0–2.8 min, 1% B; 2.8–3 min, 1–12% B; 3–5.5 min, 12% B; 5.5–5.7 min, 12–30% B; 5.7–8 min, 30% B; 8–8.2 min, 30–37% B; 8.2–14 min, 37% B; 14–14.1 min, 37–1% B; 14.1–17 min, 1% B.

[0132] The gradient elution program ⑥ is as follows: 0–2.8 min, 1% B; 2.8–3 min, 1–12% B; 3–5.5 min, 12% B; 5.5–5.7 min, 12–21% B; 5.7–8 min, 21% B; 8–8.2 min, 21–40% B; 8.2–14 min, 40% B; 14–14.1 min, 40–1% B; 14.1–17 min, 1% B.

[0133] II. Matrix Preparation

[0134] Preparation of liver S9 and intestinal S9 from SD rats: Rats were fasted for 12 hours beforehand, euthanized by cervical dislocation, and liver and small intestine segments were immediately removed, washed with PBS buffer at 4°C, chopped, and homogenized in PBS buffer. After homogenization, the mixture was centrifuged at 9000g for 20 min (4°C), the upper fat layer and lower precipitate were discarded, and the intermediate liquid was collected and aliquoted into 50mL centrifuge tubes and stored at -40°C for later use. Protein concentration was determined using the BCA method.

[0135] Preparation of SD rat plasma: Blood was collected from the venous plexus of the rat fundus, and whole blood was pre-treated with EDTA 2K. + Store the processed centrifuge tubes, centrifuge at 8000 rpm for 5 minutes, and take the upper light yellow clear liquid as plasma. Store at -40℃ for later use.

[0136] III. Sample Processing

[0137] Accurately weigh 10 mg of each compound and 10 mg of internal standard (SOF). Add 1 mL of DMSO to the internal standard and shake thoroughly to dissolve it into a colorless and clear liquid with a final concentration of 10 mg / mL. Add an appropriate amount of DMSO to the remaining compounds and shake thoroughly to dissolve them into a clear liquid with a final concentration of 50 mM. Store the resulting stock solution at 4 °C for later use and freeze at -40 °C.

[0138] Accurately transfer 1485 μL of blank plasma and preheat it in a 37°C water bath for 5 min. Then, add 15 μL of each stock solution to initiate the hydrolysis reaction (the final drug concentration in the system is 0.5 mM, and DMSO does not exceed 1%). After incubation in a 37°C water bath for 5 min, 10 min, 15 min, 30 min, 1 h, 2 h, and 4 h, take 50 μL of the incubated sample and add 100 μL of ice-cold acetonitrile (containing internal standard SOF 100 μg / mL) to terminate the reaction. Vortex for 5 min, and centrifuge twice at 12000 rpm for 5 min each time. Take 75 μL of the supernatant and inject it for analysis to determine the drug concentration. The experiment was repeated in triplicate (n=3).

[0139] After determining the protein concentration using the BCA method, all tissue S9 samples were uniformly diluted to 0.2 mg / mL with ice-cold PBS (operated on ice). 1485 μL of diluted SD rat liver and intestine S9 were precisely transferred and preheated in a 37°C water bath for 5 min. Then, 15 μL of each stock solution from section 2.2 were added to initiate the hydrolysis reaction (the final drug concentration in the system was 0.5 mM, and DMSO did not exceed 1%). After incubation at 37°C for 5 min, 10 min, 15 min, 30 min, 1 h, 2 h, and 4 h, 50 μL of the incubated sample was taken and 100 μL of ice-cold acetonitrile (containing 100 μg / mL internal standard SOF) was added to terminate the reaction. The mixture was vortexed for 5 min and centrifuged twice at 12000 rpm for 5 min each time. 75 μL of the supernatant was collected for analysis to determine the drug concentration. The experiment was repeated in triplicate (n=3).

[0140] IV. Experimental Results

[0141] Using the established HPLC method, a standard curve was plotted, the residual concentration of the drug in the incubation system was detected, and a concentration-time curve was plotted. A nonlinear regression was performed with time (X, min) on the x-axis and the residual concentration of the compound (Y, μM) on the y-axis. Integrating both sides yielded an exponential decay equation, and the half-life was calculated. The results are shown in the table below:

[0142] Table 1. In vitro stability of compounds

[0143]

[0144]

[0145] The ATV006 structure is as follows:

[0146]

[0147] Experimental results show that, compared with the isobutyl ester prodrug compound ATV006, several compounds involved in this invention (I-4, I-5, I-7, I-8, I-10 to I-17, I-19, I-21, I-23, I-24) exhibit better stability in intestinal S9, suggesting that the compounds can effectively avoid first-pass elimination in the intestine. In liver S9 and plasma, several compounds (I-4, I-12, I-19, I-23, I-24) show ideal degradation trends and can be metabolized into the active molecule GS-441524 (with appendages). Figure 3 and 4 This suggests that these compounds can better achieve metabolic activation in the liver and plasma, which is beneficial for the exposure of GS-441524 in plasma and lung tissue.

[0148] Example 20: In vivo pharmacokinetic study

[0149] I. Instruments and Materials

[0150] Ultra-high performance liquid chromatography-tandem quadrupole mass spectrometry (including two Shimadzu LC-20A infusion pumps, a SIL-20AC autosampler, a CTO-20A column oven, and a CBM-20A system controller; AB SCIEX mass spectrometry system API4000, and an ESI electrospray ionization source); Analyst 1.5.1 workstation; XSelect HSS T3 column (4.6×150mm, 3.5μm; Waters, Canada); AUW 120D electronic analytical balance (Shimadzu, Japan); Eppendorf AG 22331 centrifuge (Hamburg, Germany); XW-80A vortex mixer (Shanghai Medical University Instrument Factory); Thermo Mixer C shaker (Eppendorf, Hamburg, Germany); Sorfwall high-speed refrigerated centrifuge (Thermo Mixer C). Fishers Scientific (USA); -80°C ultra-low temperature freezer (Thermo Fishers Scientific, USA); Milli-Q Gradient A10 ultrapure water system (Millipore, Amsterdam, The Netherlands), etc. The purity of the compound and internal standard sofosbuvir is >98%.

[0151] II. Animal Experiments

[0152] Thirty SD rats were randomly divided into five groups of six each. The dose administered via gavage (ig) to each group was 0.15 mmol / kg. The pharmacokinetic characteristics of each drug, its prodrug, and its metabolites in SD rats after a single dose were investigated. Each drug was accurately weighed and prepared into a solution or suspension using 5% DMSO-95% 0.5% CMC-Na solution (v / v) for gavage (ig).

[0153] SD rats in each group were fasted for 12 hours before drug administration, but water was allowed. Blood samples of 0.3 mL were collected from the orbital sinus at 0.25, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 36, and 48 hours after drug administration. The samples were centrifuged at 8000 rpm for 5 min in 1.5 mL centrifuge tubes pre-treated with EDTA-2Na anticoagulation. 100 μL of the supernatant plasma was collected, and 5 μL of citric acid (2M) and 5 μL of NaF (0.2M) were added to inhibit enzyme activity. The mixture was vortexed thoroughly and stored at -80℃ until analysis. Plasma sample pretreatment was as follows: SD rat plasma samples were thawed at room temperature. 50 μL of plasma was collected, and ice-cold acetonitrile containing 100 ng / mL internal standard (SOF) was added to precipitate proteins. After vortexing for 5 min, the samples were centrifuged twice at 18000 rpm (4℃) for 5 min. The supernatant was then analyzed by LC-MS / MS.

[0154] After blood collection, rats were euthanized by femoral artery effusion, cervical dislocation, and thoracic and abdominal cavities were opened. Liver, kidney, and lung tissues were collected (all procedures were performed on ice). All tissues were washed with ice-cold PBS to remove blood clots, and after blotting with filter paper to remove excess moisture, all tissues were rapidly cryopreserved in liquid nitrogen. The cryopreserved rat tissues were prepared at a ratio of tissue weight to homogenate volume (g / v) of 1 / 5, and all tissue homogenate samples were stored at -80°C for analysis.

[0155] III. LC-MS / MS Experiments

[0156] 1. Liquid phase conditions

[0157] The chromatographic column used was an XSelect HSS T3 column (4.6 × 150 mm, 3.5 μm). The mobile phase consisted of an aqueous solution containing 0.1% formic acid (phase A) and a solution containing 0.1% formic acid and acetonitrile. The column temperature was 40 °C, the flow rate was 0.6 mL / min, and the gradient elution program was: 0–2 min, 1% B; 2–10 min, 1–90% B; 10–11 min, 90% B; 11–12 min, 90% B; 12–15 min, 1% B. The injection volume was 5 μL.

[0158] 2. Mass spectrometry conditions

[0159] The mass spectrometer used an electrospray ionization (ESI) source with the following parameters: Curtain Gas (CUR) 35 Arb; Collision Gas (CAD, N2) 10 Arb; Ion Spray Voltage (IS) 5500 V; Ion Source Temperature (TEM) 550 °C; Ion Source Gas 1 60 Arb; Ion Source Gas 2 65 Arb. Positive ion mode was used to scan each analyte; multiple reaction monitoring (MRM) mode was used to detect the sample. The entrance potential voltage (EP) for Q0 was set to 10 V, and the exit potential voltage (CXP) for Q2 was set to 15 V.

[0160] 3. Data Analysis

[0161] The pharmacokinetic parameters were calculated by fitting the plasma drug concentration of SD rats after drug administration to the Phoenix WinNolin 6.4 non-compartmental model (NACand Toolbox, NAC).

[0162] IV. Experimental Results

[0163] The pharmacokinetic behavior and pharmacokinetic parameters of the prodrug and metabolite GS-441524 in plasma and tissues of SD rats are shown in the appendix. Figure 5 and 6 .

[0164] Appendix Figure 5 In this study, we selected GS-5245 (ATV006) as the control compound. Compounds I-4, I-5, and GS-5245 (0.15 mmol / kg) were administered orally, and the pharmacokinetic properties of the common metabolite GS-441524 of the three prodrugs were compared. The results showed that the AUC of GS-441524 in compound I-4 (Cpd 4) was 0.5 times that of the administered GS-5245. max It is 0.45 times that of the administered GS-5245, while T max It is 4.2 times that of the drug GS-5245, T 1 / 2 It lasted 3 times longer than the administration of GS-5245.

[0165] The results suggest that the novel prodrug designed in this invention is beneficial for prolonging the plasma half-life of the metabolite GS-441524; with EC 90 Based on a 1 μM concentration (referencing existing literature), compound I-4 has a more desirable effective concentration duration of approximately 11 hours, while GS-5245 has an effective duration of 8 hours.

[0166] In addition, we evaluated the tissue distribution characteristics after gavage administration of different prodrugs (0.15 mmol / kg). First, we quantified the key metabolite GS-441524 in the lungs and plasma after 4 hours and calculated the lung-to-blood ratio. The results are shown in the table below. The experimental results show that the compound of the present invention can be metabolized into GS-441524 in vivo and has an unexpectedly high lung-to-blood ratio; this suggests that the prodrug of the present invention can facilitate the exposure of GS-441524 in the lungs and the exertion of the drug efficacy.

[0167] Table 1: Ratio of GS-441524 exposure in lung tissue and plasma after administration of different compounds.

[0168]

[0169]

[0170] The triphosphate metabolite RTP is a key metabolite for ultimately exerting antiviral efficacy. We then investigated the 4-hour RTP exposure of the compound in lung tissue. Experimental results (see attached...) Figure 6After modifying GS-441524 into a prodrug, the content of RTP in the lungs increased significantly. Furthermore, the prodrug compounds of this invention possess excellent pharmacokinetic properties and can effectively increase the content of RTP in the lungs, suggesting that compounds I-4, I-12, and I-24 all have ideal antiviral activity.

[0171] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that those skilled in the art can make improvements or modifications based on the above description, and such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A prodrug derivative of GS-441524, the structural formula of which is shown in formula (I): in, R 1 Selected from: benzyl, n is selected from: 0 or 1; m is selected from: 0 or 1; W is selected from: When R 1 When selected from benzyl, R 2 Selected from H, acetyl, propionyl, n-butyryl, cyclopropylformyl, or cyclobutylformyl; when R 1 Selected from At that time, R 2 Selected from H, propionyl, n-butyryl, isobutyryl, cyclopropylformyl, or cyclobutylformyl; R 3 Selected from: H or methyl; R 4 Selected from: H or methyl.

2. The prodrug derivative according to claim 1, characterized in that, R 1 Selected from: benzyl, n is selected from: 0 or 1; m is selected from: 0 or 1; W is selected from: When R 1 When selected from benzyl, R 2 Selected from: H, or cyclobutylformyl, R 1 Selected from At that time, R 2 Selected from H, isobutyryl, or cyclobutylformyl; R 3 Selected from: H or methyl; R 4 Selected from: H or methyl.

3. The prodrug derivative according to claim 2, characterized in that, The compound of formula (I) is any compound or combination thereof having the following structure:

4. A pharmaceutical composition, characterized in that... A prodrug derivative of GS-441524 comprising any one of claims 1-3 or a pharmaceutically acceptable salt thereof.

5. The pharmaceutical composition according to claim 4, characterized in that... The pharmaceutical composition further comprises a pharmaceutically acceptable carrier.

6. Use of the prodrug derivative of GS-441524 of claim 1 or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating coronavirus infection.

7. The application according to claim 6, characterized in that... The coronaviruses mentioned are selected from: Severe Acute Respiratory Syndrome Coronavirus SARS-CoV, 2019 novel coronavirus, Middle East Respiratory Syndrome Coronavirus, human coronavirus OC43, human coronavirus 229E, human coronavirus NL63, and human coronavirus HKUl.

8. Use of the pharmaceutical composition of claim 4 or 5 in the preparation of a medicament for treating coronavirus infection.

9. The application according to claim 8, characterized in that... The coronaviruses mentioned are selected from: Severe Acute Respiratory Syndrome Coronavirus SARS-CoV, 2019 novel coronavirus, Middle East Respiratory Syndrome Coronavirus, human coronavirus OC43, human coronavirus 229E, human coronavirus NL63, and human coronavirus HKUl.

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