Inhibitor of targeting ribosome frameshift element as well as preparation method and application of inhibitor

Abstract

The invention belongs to the technical field of medicinal chemistry, and particularly discloses an inhibitor of a targeted ribosome frameshift element as well as a preparation method and application of the inhibitor. The inhibitor of the targeting ribosome frameshift element is a thiazolo tetrahydropyridine compound and a pharmaceutically acceptable salt thereof; the structural formula of the thiazolo tetrahydropyridine compound is shown in the specification, and the inhibitor of the targeted ribosome frame-shift element disclosed by the invention has obvious binding activity with the targeted ribosome frame-shift element, can inhibit the activity of the targeted ribosome frame-shift element, and has an inhibiting effect on proliferation of various coronaviruses.

Description

Technical Field

[0001] This invention relates to the field of medicinal chemistry, and in particular to an inhibitor targeting ribosomal frameshift elements, its preparation method, and its application. Background Technology

[0002] SARS-CoV-2 is an enveloped virus with a linear single-stranded positive-sense RNA genome, approximately 60–140 nm in diameter. Its genome has a complex structure, containing multiple open reading frames (ORFs) that encode various structural and non-structural proteins. These proteins play key roles in viral replication, transcription, assembly, and release.

[0003] Currently, treatment strategies for SARS-CoV-2 mainly involve the development of drugs that directly target viral proteins, such as small molecule drugs targeting the viral 3CLpro protease and RdRp (RNA-dependent RNA polymerase). However, these drugs have some limitations, including controversial clinical efficacy, limited use, risk of drug resistance, and potential toxicity issues. Furthermore, with the continuous mutation of the virus, the efficacy of existing drugs may be further affected. Therefore, finding new drug targets and developing antiviral drugs with novel mechanisms is particularly important.

[0004] In the viral life cycle, the frameshift stimulation element (FSE) is a crucial RNA sequence that regulates the life cycle of coronaviruses and is widely present in various RNA viruses. FSEs induce programmable frameshifts in ribosomes during translation, enabling single mRNAs to encode proteins with distinct functions, thus achieving multidimensional regulation of gene expression. In coronaviruses, FSEs primarily drive differential expression of polyproteins through -1-programmed ribosome frameshifts (-1PRFs), serving as a vital regulatory hub in the viral replication cycle. For example, in the 5′ region of the SARS-CoV-2 genome, the -1PRF allows ribosomes to bypass the stop codon of ORF1a and enter ORF1b to continue encoding proteins, generating two polyprotein precursors, pp1a and pp1ab. These precursors are then cleaved by viral proteases, producing 16 non-structural proteins (NSPs). These NSPs synergistically regulate viral genome replication, mediate host immune escape, and participate in the molecular regulatory network of viral infection and pathogenesis mechanisms. Therefore, FSE plays an irreplaceable role in the replication and spread of coronaviruses and is a key regulatory element in the viral life cycle.

[0005] In the research direction of drug repurposing, multiple research teams are dedicated to exploring the application potential of existing drugs in FSE inhibition. For example, the aminoglycoside antibiotic genimycin has been found to have antiviral activity against SARS-CoV-2. Furthermore, azithromycin has been shown to reduce -1PRF efficiency by directly binding to the pseudoknot of FSE, preventing the translational conversion of viral proteins from ORF1a to ORF1b, thereby reducing the core components of the viral replication and transcription complex and inhibiting viral replication. However, these compounds discovered through drug repurposing often suffer from significant cytotoxicity, limiting their further application.

[0006] Besides repurposing existing drugs, researchers are also screening a large number of compounds to find small molecules with FSE inhibitory activity. For example, using computer-aided drug design and high-throughput screening techniques, some unmarketed compounds have been found to have potential FSE inhibitory activity. Melafloxacin is one such example, exhibiting strong inhibitory efficacy against -1PRF at the cellular level, while also possessing significant antiviral activity. However, the binding activity of melafloxacin to FSE still needs further investigation, and its exact mechanism of frameshift inhibition remains unclear. Another example is compound KCB261770, which shows significant efficacy in inhibiting -1PRF of MERS-CoV and SARS-CoV-2 and is effective against multiple coronaviruses, but its cytotoxicity is relatively high, requiring chemical modification to enhance activity and reduce toxicity.

[0007] Free-element RNA (FSE) targets offer significant advantages as a potential drug target. First, FSEs are highly conserved across various coronaviruses, suggesting that drugs designed based on this target could potentially exhibit broad-spectrum inhibitory effects against different coronaviruses, providing a robust drug reserve to address emerging variants. Second, FSEs are RNA elements, and compared to traditional protein targets, RNA exhibits greater dynamics and structural diversity, offering more opportunities for small molecule drug design. However, RNA-targeted drug development also faces numerous challenges, such as the structural complexity, dynamics, and complex interactions with proteins. Nevertheless, recent advancements in RNA structure identification and high-throughput screening technologies have led to progress in the development of small molecule inhibitors targeting RNA.

[0008] In summary, FSE, as a key viral RNA element, plays a crucial role in the life cycle of coronaviruses and is a highly promising antiviral drug target. Developing small-molecule inhibitors targeting FSE not only provides a new strategy for the treatment of COVID-19 but may also have broad-spectrum therapeutic effects against diseases caused by other coronaviruses, possessing significant scientific and clinical application value. Therefore, in-depth research into the structure and function of FSE, exploring its interaction mechanism with small-molecule inhibitors, and designing and developing highly effective FSE small-molecule inhibitors are of significant strategic importance for addressing current and future coronaviruses. Summary of the Invention

[0009] In view of this, the present invention provides an inhibitor targeting ribosomal frameshift elements, its preparation method and application, to solve the above-mentioned technical problems.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] An inhibitor targeting ribosomal frameshift elements, wherein the inhibitor targeting ribosomal frameshift elements is a thiazolytetrahydropyridine compound or a pharmaceutically acceptable salt thereof;

[0012] The structural formula of the thiazo[a]tetrahydropyridine compound is as follows:

[0013] R1 is independently selected from aromatic rings, substituted aromatic rings, aromatic heterocycles, or substituted aromatic heterocycles;

[0014] R2 is independently selected from tert-butoxycarbonyl, alkyl, cycloalkyl, phenyl, and substituted phenyl groups;

[0015] X is selected from either NH or O.

[0016] Preferably, the pharmaceutically acceptable salt of the thiazotetrahydropyridine compound comprises an acid addition salt formed with an acid;

[0017] The acid includes one or more of hydrogen chloride, hydrogen bromide, sulfuric acid, carbonic acid, oxalic acid, citric acid, succinic acid, tartaric acid, phosphoric acid, lactic acid, pyruvic acid, acetic acid, maleic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and ferulic acid.

[0018] Preferably, when R1 is an aromatic ring or a substituted aromatic ring, and R2 is a tert-butyloxycarbonyl group, The preparation method is as follows:

[0019] 1) It reacts with thiourea to obtain

[0020] 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain...

[0021] The general structural formula of the carboxylic acid is R1-COOH.

[0022] Preferably, when R1 is an aromatic ring, a substituted aromatic ring, a heterocyclic aromatic ring, or a substituted heterocyclic aromatic ring, and R2 is a methyl group, The preparation method is as follows:

[0023] 1) It reacts with thiourea to obtain

[0024] 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain...

[0025] The general structural formula of the carboxylic acid is R1-COOH.

[0026] Preferably, when R1 is an aromatic ring or a substituted aromatic ring, and R2 is an alkyl group other than methyl, a cycloalkyl group, a phenyl group, or a substituted phenyl group, The preparation method is as follows:

[0027] 1) It reacts with thiourea to obtain

[0028] 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain...

[0029] 3) It reacts with trifluoroacetic acid to obtain,

[0030] 4) The mixture is reacted with N,N-diisopropylethylamine and a halogen-containing compound to obtain

[0031] The carboxylic acid has the general structural formula R1-COOH, and the halogenated compound has the general structural formula Y-R2, where Y is selected from one of F, Cl, Br, and I.

[0032] Preferably, when R1 is 2-naphthyl or 2-naphthylmethyl, R2 is methyl, and X is NH, The preparation method is as follows:

[0033] 1) An amino-containing compound, N,N-diisopropylethylamine, and 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate were mixed with an organic solvent and reacted to obtain...

[0034] The amino-containing compound includes one of 2-naphthylamine and 2-naphthylmethylamine.

[0035] Preferably, when R1 is naphthyl or naphthylmethyl, R2 is methyl, and X is O, The preparation method is as follows:

[0036] 1) A hydroxyl-containing compound, 4-dimethylaminopyridine, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride are mixed with an organic solvent and reacted to obtain...

[0037] The hydroxyl-containing compound includes one of 2-naphthol and 2-naphthylethanol.

[0038] Preferably, when R1 is 2-naphthyl and R2 is methyl, The preparation method is as follows:

[0039] 1) The reaction with N,N-diisopropylethylamine and diphenylphosphohydrazine yields

[0040] 2) Reaction with 5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridine-2-amine yields

[0041] Another object of the present invention is to provide the use of an inhibitor targeting the ribosomal frameshift element in the preparation of a medicament for treating or preventing coronavirus infection.

[0042] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0043] The novel FSE inhibitors designed and synthesized in this invention can be used for the prevention and treatment of coronavirus infection. The small molecule compounds prepared in this invention can bind to key structural regions (such as stems, loops, and pseudoknots) in FSEs, regulating their conformational stability or dynamic equilibrium, thereby inhibiting their ability to induce -1 frameshifting of ribosomes. This mechanism blocks the viral multi-protein expression strategy, thus interfering with its life cycle and achieving an antiviral effect. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 Binding-dissociation curves of compound 1 prepared in this invention with FSE at different concentrations;

[0046] Figure 2 The binding response curves of compound 1 prepared in this invention at different concentrations with FSE are shown.

[0047] Figure 3 The results show the antiviral activity evaluation of compound 1 prepared in this invention. Detailed Implementation

[0048] This invention provides an inhibitor targeting ribosomal frameshift elements, wherein the inhibitor is a thiazolytetrahydropyridine compound or a pharmaceutically acceptable salt thereof;

[0049] The structural formula of the thiazo[a]tetrahydropyridine compound is as follows:

[0050] R1 is independently selected from aromatic rings, substituted aromatic rings, aromatic heterocycles, or substituted aromatic heterocycles;

[0051] R2 is independently selected from tert-butoxycarbonyl, alkyl, cycloalkyl, phenyl, and substituted phenyl groups;

[0052] X is selected from either NH or O.

[0053] In this invention, the aromatic ring in R1 can specifically be phenyl, 1-naphthyl, 2-naphthyl, 2-anthrayl, 2-phenanthyl, 3-phenanthyl, 9-phenanthyl, or 1-pyrene; the substituted aromatic ring can specifically be 4-benzylphenyl, 2-cyanophenyl, 3-cyanophenyl, 4-cyanophenyl, 2-bromophenyl, 3-bromophenyl, 4-bromophenyl, 2-pyridine-4-phenyl, 3-pyridine-4-phenyl, 4-pyridine-4-phenyl, 2-pyrimidin-4-phenyl, 5-pyrimidin-4-phenyl, [1,1'-biphenyl] [1,1'-biphenyl]-3-yl, [1,1'-biphenyl]-4-yl, 1,5-benzodioxazol-6-yl, 1,3-benzodioxazol-5-yl, 1-nitro-2-naphthyl, 1-methoxy-2-naphthyl, 1-bromo-2-naphthyl, 3-bromo-2-naphthyl, 3-methoxy-2-naphthyl, 4-bromo-2-naphthyl, 5-chloro-2-naphthyl, 5-bromo-2-naphthyl, 6-fluoro-2-naphthyl, 6-chloro-2-naphthyl, 6-bromo-2-naphthyl, 6-methyl-2-naphthyl, 6 -formaldehyde-2-naphthyl, 6-acetyl-2-naphthyl, 6-methoxycarbonyl-2-naphthyl, 6-amino-2-naphthyl, 6-dimethylamino-2-naphthyl, 6-hydroxy-2-naphthyl, 6-methoxy-2-naphthyl, 6-ethoxy-2-naphthyl, 6-acetoxy-2-naphthyl, 7-bromo-2-naphthyl, 7-methoxy-2-naphthyl or 2-naphthylmethyl; the aromatic heterocyclic ring can specifically be 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 2-indole The substituted aromatic heterocycles can be 5-phenyl-2-pyridyl, 2-phenyl-5-pyridyl, 2-phenyl-5-pyrimidinyl, 5-phenyl-2-pyrimidinyl, 4-methoxy-2-quinazolinyl, 6-nitro-2-quinolinyl, 7-trifluoromethyl-2-quinolinyl, 8-trifluoromethyl-2-quinolinyl, or 8-bromo-2-quinolinyl.

[0054] In this invention, the alkyl group in R2 can specifically be methyl, ethyl, propyl, isopropyl, carbamoimide, methoxymethyl, or 2-methylallyl; the cycloalkyl group can specifically be methylcyclopropyl, 2-ethylpiperidinyl, 2-ethylcyclohexyl, or 2-ethylmorpholinyl; the substituted phenyl group can specifically be benzyl, phenethyl, 3-fluorobromobenzyl, 3,4-dimethoxybenzyl, 3,5-dimethoxybenzyl, 4-nitrobenzyl, or 4-trifluoromethylbenzyl.

[0055] In this invention, the thiazolyl tetrahydropyridine compound can specifically be:

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066] In this invention, the pharmaceutically acceptable salt of the thiazotetrahydropyridine compound comprises an acid addition salt formed with an acid; the acid comprises one or more of hydrogen chloride, hydrogen bromide, sulfuric acid, carbonic acid, oxalic acid, citric acid, succinic acid, tartaric acid, phosphoric acid, lactic acid, pyruvic acid, acetic acid, maleic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and ferulic acid.

[0067] This invention also provides a method for preparing an inhibitor targeting ribosome frameshift elements, wherein R1 is an aromatic ring or a substituted aromatic ring, and R2 is a tert-butyloxycarbonyl group. The preparation method is as follows:

[0068] 1) It reacts with thiourea to obtain

[0069] 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain...

[0070] The general structural formula of the carboxylic acid is R1-COOH.

[0071] In this invention, in step 1) The molar ratio of the thiourea to thiourea is 1:1 to 1.5, preferably 1:1.1 to 1.4, and more preferably 1:1.2; the reaction temperature is preferably 80°C; and the reaction time is preferably 10 h.

[0072] In step 2), The molar ratio of the carboxylic acid, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and N,N-diisopropylethylamine is 1:1 to 2:1 to 2:3 to 7, preferably 1:1.3 to 1.6:1.4 to 1.8:4.2 to 5.4, and more preferably 1:1.5:1.5:5; the preferred reaction temperature is 40°C; and the preferred reaction time is 10 h.

[0073] This invention also provides a method for preparing an inhibitor targeting ribosomal frameshift elements, wherein R1 is an aromatic ring, a substituted aromatic ring, an aromatic heterocycle, or a substituted aromatic heterocycle, and R2 is a methyl group. The preparation method is as follows:

[0074] 1) It reacts with thiourea to obtain

[0075] 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain...

[0076] The general structural formula of the carboxylic acid is R1-COOH.

[0077] In this invention, in step 1) The molar ratio of the thiourea to thiourea is 1:1 to 1.5, preferably 1:1.1 to 1.4, and more preferably 1:1.2; the reaction temperature is preferably 80°C; and the reaction time is preferably 10 h.

[0078] In step 2), The molar ratio of the carboxylic acid, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and N,N-diisopropylethylamine is 1:1 to 2:1 to 2:3 to 7, preferably 1:1.3 to 1.6:1.4 to 1.8:4.2 to 5.4, and more preferably 1:1.5:1.5:5; the preferred reaction temperature is 40°C; and the preferred reaction time is 10 h.

[0079] This invention also provides a method for preparing an inhibitor targeting ribosomal frameshift elements, wherein when R1 is an aromatic ring or a substituted aromatic ring, and R2 is an alkyl group other than methyl, a cycloalkyl group, a phenyl group, or a substituted phenyl group, The preparation method is as follows:

[0080] 1) It reacts with thiourea to obtain

[0081] 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain...

[0082] 3) It reacts with trifluoroacetic acid to obtain,

[0083] 4) The mixture is reacted with N,N-diisopropylethylamine and a halogen-containing compound to obtain

[0084] The carboxylic acid has the general structural formula R1-COOH, and the halogenated compound has the general structural formula Y-R2, where Y is selected from one of F, Cl, Br, and I.

[0085] In this invention, in step 1) The molar ratio of the thiourea to thiourea is 1:1 to 1.5, preferably 1:1.1 to 1.4, and more preferably 1:1.2; the reaction temperature is preferably 80°C; and the reaction time is preferably 10 h.

[0086] In step 2), The molar ratio of the carboxylic acid, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and N,N-diisopropylethylamine is 1:1 to 2:1 to 2:3 to 7, preferably 1:1.3 to 1.6:1.4 to 1.8:4.2 to 5.4, and more preferably 1:1.5:1.5:5; the preferred reaction temperature is 40°C; and the preferred reaction time is 10 h.

[0087] In step 3) The mass ratio of the reagent to trifluoroacetic acid is 1:3 to 7, preferably 1:4 to 6, and more preferably 1:5; the reaction temperature is preferably room temperature; and the reaction time is preferably 6 hours.

[0088] In step 4) The molar ratio of the halogenated compound and N,N-diisopropylethylamine is 1:1 to 2:2 to 5, preferably 1:1.1 to 1.3:2.5 to 3.5, and more preferably 1:1.2:3; the reaction temperature is preferably 50°C; and the reaction time is preferably 5 hours.

[0089] This invention also provides a method for preparing an inhibitor targeting ribosomal frameshift elements, wherein R1 is 2-naphthyl or 2-naphthylmethyl, R2 is methyl, and X is NH. The preparation method is as follows:

[0090] 1) An amino-containing compound, N,N-diisopropylethylamine, and 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate were mixed with an organic solvent and reacted to obtain...

[0091] The amino-containing compound includes one of 2-naphthylamine and 2-naphthylmethylamine.

[0092] In this invention, The molar ratio of the amino compound, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and N,N-diisopropylethylamine is 1:1 to 2:1 to 2:3 to 7, preferably 1:1.3 to 1.6:1.4 to 1.8:4.2 to 5.4, and more preferably 1:1.5:1.5:5; the reaction temperature is preferably 40°C; and the reaction time is preferably 10 h.

[0093] This invention also provides a method for preparing an inhibitor targeting ribosomal frameshift elements, wherein R1 is naphthyl or naphthylmethyl, R2 is methyl, and X is O. The preparation method is as follows:

[0094] 1) A hydroxyl-containing compound, 4-dimethylaminopyridine, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride are mixed with an organic solvent and reacted to obtain...

[0095] The hydroxyl-containing compound includes one of 2-naphthol and 2-naphthylethanol.

[0096] In this invention, The molar ratio of the hydroxyl-containing compound, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 4-dimethylaminopyridine is 1:1-2:1-2:1-3, preferably 1:1.3-1.6:1.4-1.8:1.7-2.6, and more preferably 1:1.5:1.5:2; the reaction temperature is preferably 40°C; and the reaction time is preferably 10 h.

[0097] This invention also provides a method for preparing an inhibitor targeting the ribosomal frameshift element, wherein when R1 is 2-naphthyl and R2 is methyl, The preparation method is as follows:

[0098] 1) The reaction with N,N-diisopropylethylamine and diphenylphosphohydrazine yields

[0099] 2) Reaction with 5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridine-2-amine yields

[0100] In this invention, in step 1) The molar ratio of diphenylphosphohydride to N,N-diisopropylethylamine is 1:1 to 2:2 to 4, preferably 1:1.3 to 1.6:2.3 to 3.6, and more preferably 1:1.5:3; the reaction temperature is preferably 110°C, and the reaction time is preferably 5 h.

[0101] In step 2), The molar ratio of 5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridine-2-amine is 1:1 to 2, preferably 1:1.3 to 1.6, and more preferably 1:1.5; the reaction temperature is preferably 80°C, and the reaction time is preferably 10 h.

[0102] The present invention also provides the use of an inhibitor targeting the ribosomal frameshift element in the preparation of a medicament for treating or preventing coronavirus infection.

[0103] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0104] Example 1: 2-(biphenyl-4-carboxamido)-6,7-dihydrothiazo[5,4-c]pyridine-5(4H)-carboxylic acid tert-butyl ester (compound 6)

[0105] Add to a 250mL round-bottom flask (5.00 g, 17.98 mmol, 1 eq) and 70 mL of ethanol were added, stirred at room temperature for 5 min, and then thiourea (2.05 g, 26.96 mmol, 1.2 eq) was added. The mixture was heated and stirred at 80 °C for 10 h. The reaction was stopped after TLC monitoring showed complete reaction. After cooling, water was added, and a brown solid precipitated. The precipitate was filtered and washed with water. The mixture was then slurried using a PE:EA mixture of 10:1 and filtered to obtain the brown solid. (3.45-3.77g), yield 75.2-82.1%. 1H NMR(400MHz,DMSO-d6)δ6.81(s,2H),4.29(s,2H),3.56(t,J=5.9Hz,2H),2.43(t,J=6.0Hz,2H),1.41(s,9H).MS(ESI)calcd for C11H18N3O2S[M+H]+m / z 256.1120. found 256.1111.

[0106] In a 100 mL round-bottom flask, add 4-phenylbenzoic acid (582 mg, 2.94 mmol, 1.5 eq), 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (1.12 g, 2.94 mmol, 1.5 eq), and 10 mL of N,N-dimethylformamide. Stir at room temperature for 30 min, then add N,N-diisopropylethylamine (1.47 g, 9.79 mmol, 5 eq) and... (500 mg, 1.96 mmol, 1 eq), reacted at 40 °C for 10 h. The reaction was stopped after TLC and LC-MS monitoring for complete reaction. 100 mL of water was added to the reaction mixture, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (PE:EA = 10:1-1:1) to give compound 6 (555 mg). Yellow solid, yield 65.1%. mp 181.7-184.2 °C. 1H NMR (400MHz, DMSO-d6) δ12.66(s,1H),8.21(d,J=8.3Hz,2H),7.87(d,J=8.4Hz,2H),7.79(d,J=7.1Hz,2H),7.53(t ,J=7.4Hz,2H),7.45(t,J=7.3Hz,1H),4.56(s,2H),3.70(t,J=5.7Hz,2H),2.72(t,J=5.9Hz,2H),1.46(s,9H).13C NMR(151MHz,DMSO-d6)δ164.9,157.2,154.4,144.4,139.3,131.3,129.6,129.3,128.8,127.4,127.2,119.3,79.8,28.5.HRMS(ESI)calcd for C24H26N3O3S[M+H]+m / z436.1689.found 436.1688.

[0107] Example 2: N-(5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridin-2-yl)-1H-indole-2-carboxamide (compound 47)

[0108] 3-Bromo-1-methylpiperidin-4-one (3.45 g, 17.98 mmol, 1 eq) and 70 mL of ethanol were added to a 250 mL round-bottom flask. After stirring at room temperature for 5 min, thiourea (2.05 g, 26.96 mmol, 1.2 eq) was added. The mixture was heated at 80 °C and stirred for 10 h. The reaction was stopped when the reaction was complete, as monitored by TLC. After cooling, water was added, and a brown solid precipitated. The precipitate was filtered and washed with water. The precipitate was then slurried using a PE:EA mixture of 10:1 and filtered to obtain the brown solid. (1.37-2.51 g), yield 45.0-82.5%. ¹H NMR (400 MHz, DMSO-d⁶) δ 6.68 (s, 2H), 3.29 (s, 2H), 2.59 (t, J = 5.8 Hz, 2H), 2.44 (t, J = 5.9 Hz, 2H), 2.31 (s, 3H). MS (ESI) calcd for C₇H₁₂N₃S[M+H]+ m / z 170.0752.found 170.0745.

[0109] In a 100 mL round-bottom flask, add 1H-indole-2-carboxylic acid (143 mg, 886.28 μmol, 1.5 eq), 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (337 mg, 886.28 μmol, 1.5 eq), and 10 mL of N,N-dimethylformamide. After stirring at room temperature for 30 min, add N,N-diisopropylethylamine (382 mg, 2.95 mmol, 5 eq) and... (100 mg, 590.86 μmol, 1 eq), reacted at 40 °C for 10 h. The reaction was stopped after TLC and LC-MS monitoring for complete reaction. 100 mL of water was added to the reaction mixture, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (DCM:MeOH = 30:1–10:1) to give compound 47 (102 mg). It was a white solid, 55.3% yield, mp 292.7–295.1 °C. 1H NMR (400MHz, DMSO-d6) δ11.88(s,1H),7.66(d,J=8.1Hz,1H),7.62(s,1H),7.47(d,J=8.1Hz,1H),7.25(t,J=7.6Hz, 1H),7.08(t,J=7.5Hz,1H),3.66(s,2H),3.17(s,1H),2.85(t,J=5.9Hz,2H),2.74(t,J=6.3Hz,2H),2.47(s,3H).13C NMR(101MHz,DMSO-d6)δ159.6,156.7,142.8,137.8,129.8,127.5,125.0,122 .6,120.7,119.2,113.0,106.2,55.4,52.3,51.7,44.9,26.3.HRMS(ESI)calcd for C16H17N4OS[M+H]+m / z 313.1117.found 313.1116.

[0110] Example 3: N-(5-phenylmethyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridin-2-yl)biphenyl-4-carboxamide (compound 7)

[0111] Add to a 250mL round-bottom flask (5.00 g, 17.98 mmol, 1 eq) and 70 mL of ethanol were added, stirred at room temperature for 5 min, and then thiourea (2.05 g, 26.96 mmol, 1.2 eq) was added. The mixture was heated and stirred at 80 °C for 10 h. The reaction was stopped after TLC monitoring showed complete reaction. After cooling, water was added, and a brown solid precipitated. The precipitate was filtered and washed with water. The mixture was then slurried using a PE:EA mixture of 10:1 and filtered to obtain the brown solid. (3.45-3.77g), yield 75.2-82.1%. 1HNMR(400MHz,DMSO-d6)δ6.81(s,2H),4.29(s,2H),3.56(t,J=5.9Hz,2H),2.43(t,J=6.0Hz,2H),1.41(s,9H).MS(ESI)calcd for C11H18N3O2S[M+H]+m / z 256.1120.found256.1111.

[0112] In a 100 mL round-bottom flask, add 4-phenylbenzoic acid (582 mg, 2.94 mmol, 1.5 eq), 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (1.12 g, 2.94 mmol, 1.5 eq), and 10 mL of N,N-dimethylformamide. Stir at room temperature for 30 min, then add N,N-diisopropylethylamine (1.47 g, 9.79 mmol, 5 eq) and... (500 mg, 1.96 mmol, 1 eq), reacted at 40 °C for 10 h. The reaction was stopped after TLC and LC-MS monitoring for complete reaction. 100 mL of water was added to the reaction solution, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (PE:EA = 10:1-1:1) to obtain... (555mg): Yellow solid, yield 65.1%. ¹H NMR (400MHz, DMSO-d6) δ 12.66 (s, 1H), 8.21 (d, J = 8.3Hz, 2H), 7.87 (d, J = 8.4Hz, 2H), 7.79 (d, J = 7.1Hz, 2H), 7.53 (t, J = 7.4Hz, 2H), 7.45 (t, J = 7.3Hz, 1H), 4.56 (s, 2H), 3.70 (t, J = 5.7Hz, 2H), 2.72 (t, J = 5.9Hz, 2H), 1.46 (s, 9H). MS (ESI) calcd for C₂₄H₂₆N₃O₃S[M+H]+ m / z 436.1695.found 436.1686.

[0113] Add 200 mg to a 100 mL round-bottom flask. Add 5 mL of dichloromethane, stir at room temperature for 5 min, then add 1 g of trifluoroacetic acid dropwise, and react at room temperature for 6 h. Monitor the reaction by TLC and LC-MS until complete, then terminate the reaction. Concentrate the reaction solution under reduced pressure, add dichloromethane, and concentrate again under reduced pressure. The crude product is... Proceed directly to the next reaction. ¹H NMR (400MHz, DMSO) δ 12.77 (s, ¹H), 8.19 (d, J = 8.3Hz, 2H), 7.86 (d, J = 8.3Hz, 2H), 7.77 (d, J = 7.5Hz, 2H), 7.52 (t, J = 7.6Hz, 2H), 7.44 (t, J = 7.3Hz, ¹H), 4.37 (s, 2H), 3.49 (t, J = 6.1Hz, 2H), 2.93 (t, J = 6.3Hz, 2H). MS (ESI) calcd for C19H18N3OS[M+H]+m / z 336.1171.found 336.1160.

[0114] Add to a 100mL round-bottom flask Compound 7 (61 mg, 357.76 μmol, 1 eq) was prepared by stirring N,N-diisopropylethylamine (45 mg, 447.19 μmol, 3 eq) and 10 mL of N,N-dimethylformamide at room temperature for 5 min, followed by dropwise addition of benzyl bromide (61 mg, 357.76 μmol, 1.2 eq). The reaction was carried out at 50 °C for 5 h. The reaction was stopped when the reaction was complete by TLC and LC-MS. 100 mL of water was added to the reaction solution, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (DCM:MeOH = 30:1-10:1) to give compound 7 (61 mg). It was a yellow solid with a yield of 48.1% and an mp value of 173.3-176.4 °C. 1 H NMR (400MHz, DMSO-d6) δ12.58(s,1H),8.18(d,J=8.4Hz,2H),7.84(d,J=8.6Hz,2H),7.77(d,J=8.6Hz,2H),7.51(t,J=7.5Hz,2H),7.43(t,J =7.3Hz,1H),7.39–7.36(m,2H),7.36–7.32(m,2H),7.28(t,J=6.4Hz,1H),3.72(s,2H),3.60(s,2H),2.86–2.77(m,2H),2.73–2.67(m,2H). 13C NMR(151MHz,DMSO-d6)δ164.89,156.87,144.37,139.35,131.42,129.56,129.28,129.24,128.87,12 8.77,127.60,127.43,127.30,127.21,126.87,120.03,61.02,50.08,49.81,26.45.HRMS(ESI)calcd for C 26 H 24 N3OS[M+H] + m / z 426.1634.found 426.1625.

[0115] Example 4: 5-Methyl-N-(naphthyl-2-yl)-4,5,6,7-tetrahydrothiazo[5,4-c]pyridine-2-carboxamide (Compound 101)

[0116] In a 100 mL round-bottom flask, add 2-naphthylamine (108 mg, 757 μmol, 1.5 eq), 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (288 mg, 757 μmol, 1.5 eq), and 10 mL of N,N-dimethylformamide. Stir at room temperature for 30 min, then add N,N-diisopropylethylamine (326 mg, 2.52 mmol, 5 eq) and... (100 mg, 504 μmol, 1 eq), reacted at 40 °C for 10 h. The reaction was stopped after TLC and LC-MS monitoring for complete reaction. 100 mL of water was added to the reaction solution, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (PE:EA = 10:1–1:1) to obtain compound 101 (92 mg). It was a yellow solid, yield 56.4%. 1 H NMR(400MHz,DMSO-d6)δ10.88(s,1H),8.51(s,1H),7.94–7.91(m,1H),7.90–7.82(m,3H),7.52–7.4 7(m,1H),7.46–7.41(m,1H),3.71(s,2H),2.93(t,J=5.9Hz,2H),2.78(t,J=5.9Hz,2H),2.40(s,3H). 13C NMR(101MHz,DMSO-d6)δ161.2,158.7,150.7,136.3,134.1,133.7,130.7,128.7, 128.0,128.0,127.0,125.6,121.5,117.6,52.4,52.0,45.1,27.0.MS(ESI)calcd for C 18 H 18 N3OS[M+H]+m / z 324.1171.found 324.1159.

[0117] Example 5: Naphthyl-2-yl-5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridine-2-carboxylate (compound 103)

[0118] In a 100 mL round-bottom flask, add 2-naphthol (109 mg, 757 μmol, 1.5 eq), 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (145 mg, 757 μmol, 1.5 eq), and 10 mL of N,N-dimethylformamide. After stirring at room temperature for 30 min, add 4-dimethylaminopyridine (123 mg, 1.01 mmol, 3 eq) and... (100 mg, 504 μmol, 1 eq) was reacted at 40 °C for 10 h. The reaction was stopped when the reaction was complete, as monitored by TLC and LC-MS. 100 mL of water was added to the reaction solution, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (PE:EA = 10:1-1:1) to give compound 103 (105 mg). It was a white solid with a yield of 64.2%. 1 HNMR (400MHz, DMSO-d6) δ7.88–7.57(m,3H),7.45–7.31(m,1H),7.29–7.20(m,1H),7.16–7.01(m,2H),3.88(s,2H),3.06–2.62(m,4H),2.38(s,3H). 13 C NMR(101MHz,DMSO-d6)δ155.8,154.2,151.8,151.6,135.1,134.7,129.8,128.2, 128.0,126.6,126.5,123.1,119.1,109.1,53.4,51.9,45.0,26.9.MS(ESI)calcd for C 18 H 17 N2O2S[M+H]+m / z 325.1011.found325.1001.

[0119] Example 6: 1-(5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridin-2-yl)-3-(naphthyl-2-yl)urea (compound 106)

[0120] In a 100 mL round-bottom flask, 2-naphtholic acid (100 mg, 581 μmol, 1 eq), diphenylphosphoazide (240 mg, 871 μmol, 1.5 eq), N,N-diisopropylethylamine (225 mg, 1.74 mmol, 3 eq), and 10 mL of toluene were added, and the mixture was reacted at 110 °C for 5 h. After the reaction was complete as monitored by TLC and LC-MS, the following was added to the reaction solution: (147 mg, 871 μmol, 1.5 eq) was reacted at 80 °C for 10 h. The reaction was terminated after TLC and LC-MS monitoring showed complete reaction. 100 mL of water was added to the reaction mixture, and the mixture was extracted with dichloromethane (25 mL × 3). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and mixed. The crude product was purified by Flash column chromatography (PE:EA = 10:1–1:1) to give compound 107 (118 mg). It was a yellow solid, yield 60.0%. 1 H NMR(400MHz,DMSO-d6)δ9.43(s,1H),8.13(s,1H),7.85–7.82(m,2H),7.52–7.44(m,2H),7.40–7.36(m,1H),7 .26–7.23(m,1H),7.18–7.16(m,1H),3.60(s,2H),2.81(t,J=5.8Hz,2H),2.67(t,J=6.0Hz,2H),2.45(s,3H). 13 C NMR(101MHz,DMSO-d6)δ158.0,152.5,137.0,134.1,129.5,129.1,128.0,127.6, 127.0,124.8,122.9,120.5,120.1,114.4,52.3,51.7,44.9,26.2.MS(ESI)calcd for C 18 H 19 N4OS[M+H]+m / z 339.1280.found 339.1267.

[0121] The preparation methods of the remaining compounds in compounds 1 to 106 are analogous to those in Examples 1 to 6.

[0122] Experimental Example 1

[0123] The construction of the FSE lentiviral vector (Fluc-FSE-Rluc) involved in this experiment was commissioned to Yunzhou Biotechnology Co., Ltd.

[0124] Lentiviral transduction: One day before transduction, HEK293T cells were injected with 5–8.5 × 10⁻⁶ cells. 4 Cells were seeded at a density of 100 cells / well into 12-well plates and cultured in a cell culture incubator. At transduction, when the cell density reached 20-30%, 0.5 ml of DMEM medium was added to each well. For lentivirus transduction, the MOI of HEK293T cells was set to 8, and Polybrene (working concentration 5 μg / ml) was added simultaneously. 24 hours after transduction, the medium in the wells was aspirated and replaced with fresh DMEM medium. 48 hours after transduction, selection was performed using 2 μg / mL Puromycin, continuing selection for 3-5 days until the blank cells underwent complete apoptosis while the experimental group cell numbers remained stable.

[0125] Cell culture: Cells were cultured in DMEM medium containing 1 μg / mL Puromycin, 10% fetal bovine serum and 1% penicillin-streptomycin and grown at 37°C and 5% CO2.

[0126] Experimental detection: Chemiluminescence assays were performed using a glow-type dual-luciferase reporter gene assay kit, following the kit's instructions. The experimental group ratios were calculated as follows: Experimental group ratio = (Experimental group F - Background F) / (Experimental group R - Background R), Control group ratio = (Control group F - Background F) / (Control group R - Background R), and the fold change was calculated as: Experimental group ratio / Control group ratio.

[0127] Table 1. Evaluation results of anti-frameshift activity

[0128]

[0129]

[0130]

[0131]

[0132] aPRF refers to the ribosome frameshift efficiency, which is the ratio of the experimental group to the control group. The smaller the value, the better the inhibitory effect of the compound on the frameshift. The data in the table were obtained from a dual-fluorescent reporter gene assay and are the average values ​​of three independent replicates.

[0133] Compound b exhibits cytotoxicity, and the test results are not entirely accurate.

[0134] As can be seen from Table 1, the compounds prepared in this invention exhibited inhibitory effects on ribosome frameshift at both 10 μM and 20 μM concentrations; the lower the value, the more significant the inhibitory effect.

[0135] Experimental Example 2

[0136] SPR combined experiment

[0137] In this experiment, to prevent RNA degradation, all water and equipment were treated with DEPC. First, the 5' end of the FSE sequence was biotin-labeled and immobilized on the SA chip using a biotin-streptavidin method, with a target response value of approximately 700 RU. For the reference lane, only the chip surface was activated and sealed; FSE immobilization was not performed.

[0138] The buffer solution used in the experiment was: 50 mM HEPES, 100 mM KCl, 10 mM MgCl2, pH 7.5. Solutions of compound 1 with different concentration gradients containing 5% DMSO were prepared, ranging from 0.2 μmol / L to 12.5 μmol / L (0.20 μM, 0.39 μM, 0.78 μM, 1.56 μM, 3.13 μM, 6.25 μM, and 12.5 μM, respectively), while ensuring that the DMSO content in the buffer solution was maintained at 5%. The compounds of different concentrations were sequentially passed through the chip surface for analysis. If a compound interacts with the FSE, a binding-dissociation signal will be generated on the SPR curve; if there is no interaction, no response signal will be generated.

[0139] After each injection, the chip was rinsed with a buffer solution to regenerate it. Binding-dissociation data were fitted using the Hill equation to calculate the dissociation equilibrium constant, thereby assessing the binding affinity of the compound to the FSE. Figure 1 and Figure 2 The binding behavior between compound 1 and SARS-CoV-2FSE was demonstrated. Figure 1 In this study, compounds of different concentrations (0.20–12.5 μM) were sequentially flowed through the surface of an SA chip immobilized with Fiber Optic Sediment (FSE). The real-time recorded SPR response curves showed a concentration-dependent binding-dissociation process. As the compound concentration increased, the response value (RU) gradually increased, indicating a specific binding between the compound and the FSE, and that the degree of binding increased with increasing concentration. Figure 2 The corresponding concentration-response fitting curve is shown. The equilibrium binding response value was fitted using the Hill equation, and the apparent dissociation constant (KD) of compound 1 with FSE was calculated to be 4.99 μM, indicating that the compound has moderate affinity and can stably bind with FSE.

[0140] Experimental Example 3

[0141] In this experiment, VERO E6 cells were used to evaluate the antiviral activity against SARS-CoV-2 (wild-type). First, VERO E6 cells were seeded in 96-well plates and cultured to the logarithmic growth phase. The cells were then infected with SARS-CoV-2 (WT) virus. After infection, the cells were cultured for 48 hours, and compound 1 was added at concentrations ranging from 0.49 to 120 μmol / L (0.49 μmol / L, 1.48 μmol / L, 4.44 μmol / L, 13.3 μmol / L, 40 μmol / L, 120 μmol / L). Following treatment, the antiviral effect was assessed using N protein immunofluorescence. Specifically, after fixing and permeabilizing the cells, they were incubated with a specific anti-SARS-CoV-2 N protein antibody, followed by the addition of a fluorescently labeled secondary antibody. Cell images were then observed and captured using a fluorescence microscope. The activity of the drug in inhibiting viral infection was evaluated by analyzing the fluorescence intensity of the N protein. Figure 3 This study presents the antiviral activity evaluation results of compound 1 against SARS-CoV-2 (wild-type) infected VERO E6 cells. The degree of viral infection was quantified using N protein immunofluorescence assay. The inhibition rate was calculated and dose-response curves were plotted by analyzing the changes in the intensity of the N protein fluorescence signal after treatment with different concentrations of the drug. The results show that compound 1 exhibits a dose-dependent antiviral effect, with an IC50 value of [missing information]. 50 The value was 6.75±2.41μM, indicating that it has certain anti-SARS-CoV-2 activity at the cellular level.

[0142] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0143] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An inhibitor targeting ribosomal frameshift elements, characterized in that, The inhibitors targeting the ribosomal frameshift element are thiazolyl tetrahydropyridine compounds and their pharmaceutically acceptable salts; The structural formula of the thiazo[a]tetrahydropyridine compound is as follows: R1 is independently selected from aromatic rings, substituted aromatic rings, aromatic heterocycles, or substituted aromatic heterocycles; R2 is independently selected from tert-butoxycarbonyl, alkyl, cycloalkyl, phenyl, and substituted phenyl groups; X is selected from either NH or O.

2. The inhibitor targeting ribosomal frameshift elements according to claim 1, characterized in that, Pharmaceutically acceptable salts of the thiazotetrahydropyridine compounds include acid addition salts formed with acids. The acid includes one or more of hydrogen chloride, hydrogen bromide, sulfuric acid, carbonic acid, oxalic acid, citric acid, succinic acid, tartaric acid, phosphoric acid, lactic acid, pyruvic acid, acetic acid, maleic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and ferulic acid.

3. A method for preparing an inhibitor targeting ribosomal frameshift elements as described in claim 1 or 2, characterized in that, When R1 is an aromatic ring or a substituted aromatic ring, and R2 is a tert-butyloxycarbonyl group... The preparation method is as follows: 1) It reacts with thiourea to obtain 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain... The general structural formula of the carboxylic acid is R1-COOH.

4. A method for preparing an inhibitor targeting ribosomal frameshift elements as described in claim 1 or 2, characterized in that, When R1 is an aromatic ring, a substituted aromatic ring, a heterocyclic aromatic ring, or a substituted heterocyclic aromatic ring, and R2 is a methyl group... The preparation method is as follows: 1) It reacts with thiourea to obtain 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain... The general structural formula of the carboxylic acid is R1-COOH.

5. A method for preparing an inhibitor targeting ribosomal frameshift elements as described in claim 1 or 2, characterized in that, When R1 is an aromatic ring or a substituted aromatic ring, and R2 is an alkyl group other than methyl, a cycloalkyl group, a phenyl group, or a substituted phenyl group, The preparation method is as follows: 1) It reacts with thiourea to obtain 2) A mixture of carboxylic acid, N,N-diisopropylethylamine, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, and an organic solvent is reacted to obtain... 3) It reacts with trifluoroacetic acid to obtain, 4) The mixture is reacted with N,N-diisopropylethylamine and a halogen-containing compound to obtain The carboxylic acid has the general structural formula R1-COOH, and the halogenated compound has the general structural formula Y-R2, where Y is selected from one of F, Cl, Br, and I.

6. A method for preparing an inhibitor targeting ribosomal frameshift elements as described in claim 1 or 2, characterized in that, When R1 is 2-naphthyl or 2-naphthylmethyl, when R2 is methyl, and when X is NH. The preparation method is as follows: 1) An amino-containing compound, N,N-diisopropylethylamine, and 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate were mixed with an organic solvent and reacted to obtain... The amino-containing compound includes one of 2-naphthylamine and 2-naphthylmethylamine.

7. A method for preparing an inhibitor targeting ribosomal frameshift elements according to claim 1 or 2, characterized in that, When R1 is naphthyl or naphthylmethyl, when R2 is methyl, and when X is O. The preparation method is as follows: 1) A hydroxyl-containing compound, 4-dimethylaminopyridine, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride are mixed with an organic solvent and reacted to obtain... The hydroxyl-containing compound includes one of 2-naphthol and 2-naphthylethanol.

8. A method for preparing an inhibitor targeting ribosomal frameshift elements according to claim 1 or 2, characterized in that, When R1 is 2-naphthyl and R2 is methyl, The preparation method is as follows: 1) The reaction with N,N-diisopropylethylamine and diphenylphosphohydrazine yields 2) Reaction with 5-methyl-4,5,6,7-tetrahydrothiazo[5,4-c]pyridine-2-amine yields 9. The use of an inhibitor targeting ribosomal frameshift elements as described in claim 1 or 2 in the preparation of a medicament for treating or preventing coronavirus infection.

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