CN110272381A - The Oseltamivir analog of the segment containing pyridine and its application - Google Patents

Abstract

The invention relates to the field of medicinal chemistry, in particular to an oseltamivir analog containing a pyridine fragment and an application thereof. The oseltamivir analog containing a pyridine fragment of the present invention or a pharmaceutically acceptable salt or isomer thereof has the general structural formula shown in formula I; wherein, R ₁ , R ₂ and R ₃ are independently selected From hydrogen, halogen, methyl, hydroxy, methoxy, nitro or amino. The present invention obtains the oseltamivir analog containing a pyridine fragment by modifying and transforming the primary amine group of oseltamivir, which exhibits an inhibitory effect on the neuraminidase activity, and has the advantages of anti-influenza virus-induced diseases. certain potential application value.

Description

Oseltamivir analogues containing pyridine fragments and their applications

technical field

The invention relates to the field of medicinal chemistry, in particular to an oseltamivir analog containing a pyridine fragment and an application thereof. The application is mainly used for treating infectious diseases caused by viruses.

Background technique

Influenza (influenza for short) is an acute respiratory infection caused by influenza virus. Influenza A is highly transmissible, and has high morbidity and mortality rates, which can easily lead to pandemics or outbreaks.

There are two main anti-influenza virus drugs, M2 protein inhibitors and neuraminidase inhibitors. M2 protein inhibitors mainly include amantadine hydrochloride and rimantadine hydrochloride. After oral absorption, amantadine hydrochloride can penetrate the blood and brain. These two drugs are not recommended for the prevention and treatment of influenza A by the CDC (Centers for Disease Control) in the United States.

Neuraminidase can promote the release of progeny viruses from host cells, so neuraminidase inhibitors can inhibit the release of viruses and block the transmission route, thereby playing a role in the treatment of influenza. The structure of the neuraminidase active center is relatively conservative, so it is an ideal target for the treatment of influenza. Drugs in this class used worldwide are zanamivir and oseltamivir phosphate. Among them, oseltamivir phosphate is the only oral drug. It can exert its efficacy after being hydrolyzed into free acid (GS4071) by esterase in the body. The active ingredient is distributed to all parts of influenza virus infection, including lung, trachea, nasal mucosa and It is recognized as one of the special drugs against influenza A and avian influenza, and it is also the largest-selling anti-influenza drug. However, the highly pathogenic H5N1 avian influenza virus and various seasonal H1N1 and H3N2 influenza strains that have appeared in recent years have shown varying degrees of resistance to oseltamivir phosphate, which greatly affects oseltamivir phosphate. Because of its therapeutic effect as a neuraminidase inhibitor, the development of an efficient neuraminidase inhibitor has always been a hot and difficult point in the field of anti-influenza virus drug research.

SUMMARY OF THE INVENTION

In view of the deficiencies of the prior art, the object of the present invention is to provide a oseltamivir analog containing a pyridine fragment and its application. The present invention obtains oseltamivir analogs containing pyridine fragments by modifying and transforming the primary amine group of oseltamivir, which exhibits an inhibitory effect on the activity of neuraminidase, and is effective in resisting diseases caused by influenza virus certain potential application value.

The present invention adopts following technical scheme:

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the general structural formula shown in formula I:

Wherein, R ₁ , R ₂ and R ₃ are independently selected from hydrogen, halogen, methyl, hydroxyl, methoxy, nitro or amino.

Further preferably, R ₁ , R ₂ , and R ₃ are independently selected from hydrogen, halogen, hydroxyl, methyl, nitro, and amino; the halogen is fluorine, chlorine, and bromine.

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the structural formula shown in formula I-1:

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the structural formula shown in formula I-2:

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the structural formula shown in formula I-3:

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the structural formula shown in formula I-4:

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the structural formula shown in formula I-5:

An oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, having the structural formula shown in formula I-6:

Preferably, the hydrate, solvate, polymorph, prodrug, enantiomer or racemic mixture of the oseltamivir analog containing a pyridine fragment is also included.

The above-mentioned oseltamivir analogues containing pyridine fragments or their pharmaceutically acceptable salts or isomers are used in the preparation of neuraminidase inhibitors and/or preparation of treatment and/or prevention and/or delay/and/or assistance The use of medicines for the treatment of diseases caused by influenza viruses.

A pharmaceutical composition comprising the above-mentioned oseltamivir analog containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof or a hydrate, solvate, polymorph, prodrug, enantiomer thereof body or racemic mixture, and at least one pharmaceutically acceptable excipient.

Further preferably, the excipient includes at least one of the following substances: solvent, emulsifier, stabilizer, preservative, propellant, solubilizer, flavoring agent, glidant, coating material, suspending agent , fragrances, anti-adhesives, penetration enhancers, pH adjusters, buffers, plasticizers, cosolvents, colorants, binders, disintegrants, fillers, lubricants, osmotic pressure regulators, surface active agents Agents, foaming agents, defoamers, thickeners, inclusion agents, humectants, absorbents, diluents, flocculants and deflocculants, filter aids, release retarders.

The pharmaceutical composition of the present invention can be made into various dosage forms: classified according to the dispersion system of the dosage form: Specifically, it can be made into the following dosage forms: solvent type, colloidal solution type, emulsion type, suspension type, gas dispersion type, particle dispersion type According to the classification of forms, specifically, the following dosage forms can be made: liquid dosage forms (such as aromatic water, solutions, injections, mixtures, lotions, etc.), gas dosage forms (such as aerosols, sprays, etc.) etc.), solid dosage forms (such as powders, pills, tablets, films, etc.), semi-solid dosage forms (such as ointments, suppositories, pastes, etc.); classified according to the route of administration: Specifically, the following dosage forms can be made: Dosage form for parenteral administration, dosage form for parenteral administration.

The beneficial effects of the present invention

In the present invention, a series of oseltamivir analogs containing pyridine fragments are obtained by modifying the primary amine group of oseltamivir, which have novel structures; generally, for neuraminidase inhibitors, the introduction of The pyridine fragment will reduce the basicity of the nitrogen atom, and the basicity of the nitrogen atom is essential for the neuraminidase inhibitor to maintain high activity, and the present invention maintains the neuraminidase by introducing the pyridine fragment to oseltamivir. The high activity of the inhibitor can inhibit the activity of neuraminidase to varying degrees, in the preparation of neuraminidase inhibitors and/or the preparation of treatment and/or prevention and/or delay/and/or adjuvant treatment of influenza virus It has a good prospect in the medicine of the disease caused by it.

Detailed ways

The present invention will be described in detail below through specific embodiments.

Example 1

An oseltamivir analog containing a pyridine fragment, its name is (3R, 4R, 5S)-4-acetamido-5-[2-(5-bromo-3-amino)pyridinamino]-3 -(1-Ethylpropoxy)-1-cyclohexene-1-carboxylic acid, having the structural formula shown in formula I-1:

The above oseltamivir analog containing pyridine fragment, its preparation method is as follows:

(1) Add oseltamivir (4.00g, 12.81mmol), potassium carbonate (2.66g, 19.25mmol) and 2-chloro-5-bromo-3-nitropyridine (3.04g, 12.81 mmol) to a 100mL round bottom flask mmol), then 25 mL of DMF was added and the reaction was stirred at 60°C. After the reaction, the reaction solution was poured into 125 mL of deionized water, the precipitate was precipitated, and the precipitate was filtered to obtain (3R,4R,5S)-4-acetamido-5-[2-(5-bromo-3-nitro)pyridine Amino]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid ethyl ester 3.28 g, yield 82.0%.

(2) The product of step (1) (411 mg, 0.800 mmol), reduced iron powder (268 mg, 4.800 mmol) and ammonium chloride (342 mg, 6.400 mmol) were added to a 50 mL round-bottomed flask, followed by 15 mL of 90% ethanol aqueous solution , stirring at reflux. After the reaction, filter, evaporate the ethanol in the filtrate, extract the aqueous phase with 2×20 mL of ethyl acetate, combine the organic phases, wash with saturated sodium chloride solution, dry over anhydrous Na ₂ SO ₄ , filter and concentrate to obtain crude The product was purified by column chromatography to obtain (3R,4R,5S)-4-acetamido-5-[2-(5-bromo-3-amino)pyridinamino]-3-(1-ethylpropoxy ethyl)-1-cyclohexene-1-carboxylate.

(3) The product of step (2) (111 mg, 0.23 mmol) was added to a 25 mL round bottom flask, followed by adding 10 mL methanol and 0.54 mL 1N NaOH aqueous solution, and adding 1.46 mL deionized water to make V methanol: V water=5 : 1. The reaction was stirred at room temperature. After the reaction, the pH of the reaction solution was adjusted with ion exchange resin (Amerlite IR120, H ⁺ form), filtered, concentrated, and purified by column chromatography to obtain the target product.

The H NMR data of the target product are as follows:

¹ H NMR (600 MHz, CD ₃ OD) δ 7.33 (d, J=5.7 Hz, 1H), 7.05 (d, J=7.6 Hz, 1H), 6.72 (s, 1H), 6.68-6.62 (m, 1H) ), 4.37–4.30 (m, 2H), 4.05–3.98 (m, 1H), 3.44–3.38 (m, 1H), 2.91 (dd, J=17.5, 4.6Hz, 1H), 2.43 (dd, J=15.2 ,10.4Hz,1H),1.74(s,3H),1.54–1.43(m,4H),0.89(t,J=7.4Hz,3H),0.83(t,J=7.4Hz,3H);

The molecular weight of the obtained product was determined by liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization (ESI): [M+H] ⁺ : 377.2, [M+Na] ⁺ : 399.2.

Example 2

An oseltamivir analog containing a pyridine fragment, its name is (3R, 4R, 5S)-4-acetamido-5-[2-(6-methoxy-3-nitro)pyridinamino ]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid, having the structural formula shown in formula I-2:

The above oseltamivir analog containing pyridine fragment, its preparation method is as follows:

(1) Add oseltamivir (4.00g, 12.81mmol), potassium carbonate (2.66g, 19.25mmol) and 2-chloro-5-methoxy-3-nitropyridine (2.41g) to a 100mL round-bottom flask , 12.81 mmol), then 25 mL of DMF was added and the reaction was stirred at 60 °C. After the reaction, the reaction solution was poured into 125 mL of deionized water, the precipitate was precipitated, and the precipitate was filtered to obtain the intermediate (3R,4R,5S)-4-acetamido-5-[2-(6-methoxy-3- Nitro)pyridinamino]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid ethyl ester.

(2) The product of step (1) (199 mg, 0.429 mmol) was added to a 25 mL round-bottomed flask, followed by adding 10 mL methanol and 1.07 mL 1N NaOH aqueous solution, and adding 0.93 mL deionized water to make V methanol: V water=5 : 1, stir the reaction at room temperature, adjust the pH to 1-2 after the reaction, precipitate out, filter, and dry to obtain the target product.

The H NMR data of the target product are as follows:

¹ H NMR (400MHz, CD ₃ OD) δ 8.96 (d, J=7.5Hz, 1H), 8.33 (d, J=9.1 Hz, 1H), 6.89 (s, 1H), 6.13 (d, J=9.1 Hz, 1H), 4.67–4.59 (m, 1H), 4.27 (dd, J=9.4, 6.8Hz, 1H), 4.20–4.14 (m, 1H), 3.97 (s, 3H), 3.49–3.41 (m, 1H), 3.03(dd, J=18.0, 5.2Hz, 1H), 2.47(ddt, J=17.9, 7.7, 2.2Hz, 1H), 1.90(s, 3H), 1.61–1.49(m, 4H), 0.94 (t, J=7.4Hz, 3H), 0.94 (t, J=7.4Hz, 3H);

The molecular weight of the obtained product was determined by high-resolution mass spectrometry (HRMS) of electrospray ionization (ESI): [M+H] ⁺ Theoretical (Calcd): 437.2031, found: 437.2059; [M+Na ] ⁺ Theoretical value (Calcd): 459.1856, the actual measured value (found): 459.1876.

Example 3

An oseltamivir analog containing a pyridine fragment, its name is (3R, 4R, 5S)-4-acetamido-5-[2-(6-methoxy-3-amino)pyridinamino] -3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid, having the structural formula shown in formula I-3:

The above oseltamivir analog containing pyridine fragment, its preparation method is as follows:

(1) Add oseltamivir (4.00g, 12.81mmol), potassium carbonate (2.66g, 19.25mmol) and 2-chloro-5-methoxy-3-nitropyridine (2.41g) to a 100mL round-bottom flask , 12.81 mmol), then 25 mL of DMF was added and the reaction was stirred at 60 °C. After the reaction, the reaction solution was poured into 125 mL of deionized water, the precipitate was precipitated, and the precipitate was filtered to obtain the intermediate (3R,4R,5S)-4-acetamido-5-[2-(6-methoxy-3- Nitro)pyridinamino]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid ethyl ester.

(2) The product of step (1) (372 mg, 0.800 mmol), reduced iron powder (268 mg, 4.800 mmol) and ammonium chloride (342 mg, 6.400 mmol) were added to a 50 mL round-bottomed flask, followed by 15 mL of 90% aqueous ethanol solution , stirring at reflux. After the reaction, filter, evaporate the ethanol in the filtrate, extract the aqueous phase with 2×20 mL of ethyl acetate, combine the organic phases, wash with saturated sodium chloride solution, dry over anhydrous Na ₂ SO ₄ , filter and concentrate to obtain crude The product was purified by column chromatography to give (3R,4R,5S)-4-acetamido-5-[2-(6-methoxy-3-amino)pyridinamino]-3-(1-ethyl propoxy)-1-cyclohexene-1-carboxylic acid ethyl ester.

(3) The product of step (2) (100 mg, 0.23 mmol) was added to a 25 mL round-bottomed flask, followed by adding 10 mL methanol and 0.54 mL 1N NaOH aqueous solution, and adding 1.46 mL deionized water to make V methanol: V water=5 : 1. The reaction was stirred at room temperature. After the reaction, the pH of the reaction solution was adjusted with ion exchange resin (Amerlite IR120, H ⁺ form), filtered, concentrated, and purified by column chromatography to obtain the target product.

The H NMR data of the target product are as follows:

¹ H NMR (600 MHz, CD ₃ OD) δ 7.45 (d, J=2.1 Hz, 1H), 6.94 (d, J=2.1 Hz, 1H), 6.72 (s, 1H), 4.34-4.29 (m, 1H) ), 4.18(d, J=8.2Hz, 1H), 4.03(dd, J=10.9, 8.7Hz, 1H), 3.46–3.41(m, 1H), 3.35(s, 3H), 2.89(dd, J= 17.5, 4.2Hz, 1H), 2.35–2.28 (m, 1H), 1.76 (s, 3H), 1.56–1.46 (m, 4H), 0.93 (t, J=7.4Hz, 3H), 0.87 (t, J = 7.4Hz, 3H);

The molecular weight of the obtained product was determined by high resolution mass spectrometry (HRMS) of electrospray ionization (ESI): [M+H] ⁺ theoretical (Calcd): 407.2289, found: 407.2291.

Example 4

An oseltamivir analogue containing a pyridine fragment, its name is (3R, 4R, 5S)-4-acetamido-5-[2-(3-amino)pyridinamino]-3-(1- Ethylpropoxy)-1-cyclohexene-1-carboxylic acid, the structural formula shown in formula I-4:

The above oseltamivir analog containing pyridine fragment, its preparation method is as follows:

(1) Oseltamivir (4.00g, 12.81mmol), potassium carbonate (2.66g, 19.25mmol) and 2-chloro-3-nitropyridine (2.03g, 12.81mmol) were added to a 100mL round bottom flask, followed by 25 mL of DMF was added and the reaction was stirred at 60°C. After the reaction, the reaction solution was poured into 125 mL of deionized water, the precipitate was precipitated, and the precipitate was filtered to obtain the intermediate (3R,4R,5S)-4-acetamido-5-[2-(3-nitro)pyridinamino ]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid ethyl ester.

(2) The product of step (1) (348 mg, 0.800 mmol), reduced iron powder (268 mg, 4.800 mmol) and ammonium chloride (342 mg, 6.400 mmol) were added to a 50 mL round-bottomed flask, followed by 15 mL of 90% ethanol aqueous solution , stirring at reflux. After the reaction, filter, evaporate the ethanol in the filtrate, extract the aqueous phase with 2×20 mL of ethyl acetate, combine the organic phases, wash with saturated sodium chloride solution, dry over anhydrous Na ₂ SO ₄ , filter and concentrate to obtain crude The product was purified by column chromatography to give (3R,4R,5S)-4-acetamido-5-[2-(3-amino)pyridinamino]-3-(1-ethylpropoxy)-1 - Ethyl cyclohexene-1-carboxylate.

(3) The product of step (2) (93 mg, 0.23 mmol) was added to a 25 mL round bottom flask, followed by adding 10 mL methanol and 0.54 mL 1N NaOH aqueous solution, and adding 1.46 mL deionized water to make V methanol: V water=5 : 1. The reaction was stirred at room temperature. After the reaction, the pH of the reaction solution was adjusted with ion exchange resin (Amerlite IR120, H ⁺ form), filtered, concentrated, and purified by column chromatography to obtain the target product.

The H NMR data of the target product are as follows:

¹ H NMR (600 MHz, CD ₃ OD) δ 7.33 (d, J=5.7 Hz, 1H), 7.05 (d, J=7.6 Hz, 1H), 6.72 (s, 1H), 6.68-6.62 (m, 1H) ), 4.37–4.30 (m, 2H), 4.05–3.98 (m, 1H), 3.44–3.38 (m, 1H), 2.91 (dd, J=17.5, 4.6Hz, 1H), 2.43 (dd, J=15.2 ,10.4Hz,1H),1.74(s,3H),1.54–1.43(m,4H),0.89(t,J=7.4Hz,3H),0.83(t,J=7.4Hz,3H);

The molecular weight of the obtained product was determined by liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization (ESI): [M+H] ⁺ : 377.2, [M+Na] ⁺ : 399.2.

Example 5

An oseltamivir analogue containing a pyridine fragment, its name is (3R, 4R, 5S)-4-acetamido-5-[2-(5-amino)pyridinamino]-3-(1- Ethylpropoxy)-1-cyclohexene-1-carboxylic acid, having the structural formula shown in formula I-5:

The above oseltamivir analog containing pyridine fragment, its preparation method is as follows:

(1) Oseltamivir (4.00g, 12.81mmol), potassium carbonate (2.66g, 19.25mmol) and 2-chloro-5-nitropyridine (2.03g, 12.81mmol) were added to a 100mL round bottom flask, followed by 25 mL of DMF was added and the reaction was stirred at 60°C. After the reaction, the reaction solution was poured into 125 mL of deionized water, the precipitate was precipitated, and the precipitate was filtered to obtain the intermediate (3R,4R,5S)-4-acetamido-5-[2-(3-nitro)pyridinamino ]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid ethyl ester.

(2) The product of step (1) (348 mg, 0.800 mmol), reduced iron powder (268 mg, 4.800 mmol) and ammonium chloride (342 mg, 6.400 mmol) were added to a 50 mL round-bottomed flask, followed by 15 mL of 90% ethanol aqueous solution , stirring at reflux. After the reaction, filter, evaporate the ethanol in the filtrate, extract the aqueous phase with 2×20 mL of ethyl acetate, combine the organic phases, wash with saturated sodium chloride solution, dry over anhydrous Na ₂ SO ₄ , filter and concentrate to obtain crude The product was purified by column chromatography to give (3R,4R,5S)-4-acetamido-5-[2-(5-amino)pyridinamino]-3-(1-ethylpropoxy)-1 - Ethyl cyclohexene-1-carboxylate.

(3) The product of step (2) (93 mg, 0.23 mmol) was added to a 25 mL round bottom flask, followed by adding 10 mL methanol and 0.54 mL 1N NaOH aqueous solution, and adding 1.46 mL deionized water to make V methanol: V water=5 : 1. The reaction was stirred at room temperature. After the reaction, the pH of the reaction solution was adjusted with ion exchange resin (Amerlite IR120, H ⁺ form), filtered, concentrated, and purified by column chromatography to obtain the target product.

The H NMR data of the target product are as follows:

¹ H NMR (600MHz, CD ₃ OD) δ 7.87 (d, J=2.5Hz, 1H), 7.82 (dd, J=9.6, 2.5Hz, 1H), 7.14 (d, J=9.6Hz, 1H), 6.81(s, 1H), 4.37(d, J=8.2Hz, 1H), 4.25-4.19(m, 1H), 3.94-3.90(m, 1H), 3.43-3.39(m, 1H), 2.83(dd, J=17.3, 5.6Hz, 1H), 2.42–2.36 (m, 1H), 1.73 (d, J=8.1Hz, 3H), 1.51–1.42 (m, 4H), 0.87 (dd, J=9.6, 5.2Hz) ,3H),0.80(t,J=7.4Hz,3H);

The molecular weight of the obtained product was determined by high resolution mass spectrometry (HRMS) of electrospray ionization (ESI): [M+H] ⁺ theoretical (Calcd): 377.2183, found: 377.2189.

Example 6

A kind of oseltamivir analog containing a pyridine fragment, its name is (3R, 4R, 5S)-4-acetamido-5-[2-(5-methyl-3-amino)pyridinamino]- 3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylic acid, having the structural formula shown in formula I-6:

The above oseltamivir analog containing pyridine fragment, its preparation method is as follows:

(1) Add oseltamivir (4.00g, 12.81mmol), potassium carbonate (2.66g, 19.25mmol) and 2-chloro-5-methyl-3-nitropyridine (2.21g, 19.25mmol) to a 100mL round bottom flask 12.81 mmol), followed by 25 mL of DMF, and the reaction was stirred at 60°C. After the reaction, the reaction solution was poured into 125 mL of deionized water, the precipitate was precipitated, and the precipitate was filtered to obtain the intermediate (3R, 4R, 5S)-4-acetamido-5-[2-(5-methyl-3-nitro yl)pyridinamino]-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate ethyl ester.

(2) The product of step (1) (359 mg, 0.800 mmol), reduced iron powder (268 mg, 4.800 mmol) and ammonium chloride (342 mg, 6.400 mmol) were added to a 50 mL round-bottomed flask, followed by 15 mL of 90% ethanol aqueous solution , stirring at reflux. After the reaction, filter, evaporate the ethanol in the filtrate, extract the aqueous phase with 2×20 mL of ethyl acetate, combine the organic phases, wash with saturated sodium chloride solution, dry over anhydrous Na ₂ SO ₄ , filter and concentrate to obtain crude The product was purified by column chromatography to obtain (3R,4R,5S)-4-acetamido-5-[2-(5-methyl-3-amino)pyridinamino]-3-(1-ethylpropane) oxy)-1-cyclohexene-1-carboxylic acid ethyl ester.

(3) The product of step (2) (96 mg, 0.23 mmol) was added to a 25 mL round-bottomed flask, followed by adding 10 mL methanol and 0.54 mL 1N NaOH aqueous solution, and adding 1.46 mL deionized water to make V methanol: V water=5 : 1. The reaction was stirred at room temperature. After the reaction, the pH of the reaction solution was adjusted with ion exchange resin (Amerlite IR120, H ⁺ form), filtered, concentrated, and purified by column chromatography to obtain the target product.

The H NMR data of the target product are as follows:

¹ H NMR (600 MHz, CD ₃ OD) δ 7.12 (s, 1H), 7.05 (d, J=1.6 Hz, 1H), 6.88 (t, J=2.0 Hz, 1H), 4.45–4.39 (m, 1H) ), 4.36–4.31 (m, 1H), 4.08–3.96 (m, 1H), 3.47–3.42 (m, 1H), 2.92 (dd, J=17.6, 5.4Hz, 1H), 2.55–2.48 (m, 1H) ), 2.19(s, 3H), 1.80(s, 3H), 1.58–1.48(m, 4H), 0.93(dd, J=9.7, 5.1Hz, 3H), 0.85(dd, J=9.3, 5.5Hz, 3H);

The molecular weight of the obtained product was determined by liquid chromatography-mass spectrometry (LC-MS) by electrospray ionization (ESI): [M+H] ⁺ : 391.0; determined by high resolution mass spectrometry (HRMS) by electrospray ionization (ESI) The molecular weight of the obtained product was obtained: [M+H] ⁺ theoretical value (Calcd): 391.2340, actual found value (found): 391.2360.

Experimental example

Inhibitory activity test of neuraminidase A/Anhui/1/2005(H5N1):

The test principle is that MUNANA (2'-(4-methylumbelliferyl)-α-N-acetylneuraminic acid) is a specific substrate of neuraminidase, and the substance generated by the metabolism of neuraminidase is excited by 355nm light. It can generate 460nm fluorescence. When the tested compound interacts with neuraminidase, the binding rate of the specific substrate changes, resulting in a change in fluorescence intensity, which reflects the activity of neuraminidase through the change in fluorescence intensity. The neuraminidase inhibition rate of the compound at this concentration was calculated.

experiment method:

Add 10 μL of enzyme-containing solution, 70 μL of buffer (33 mM morpholinoethanesulfonic acid, 4 mM CaCl ₂ ), 10 μL of test compound at a concentration of 10 μM to each well of a 96-well plate, incubate at 37°C for ten minutes, and then add 100 μM 10μL of fluorescent substrate was incubated at 37°C for 30 minutes, and 150μL of stop solution (14mM NaOH in 83% ethanol solution) was added to measure the fluorescence intensity, where the excitation wavelength was 355nm and the emission wavelength was 460nm. The positive control drug was Oseltamiviracid (OC).

The oseltamivir analogs containing pyridine fragments with the structural formulas I-1 to 6 are respectively recorded as compounds I-1 to 6, and the inhibition rates are shown in Table 1:

Table 1

compound I-1 I-2 I-3 I-4 I-5 I-6 OC Inhibition rate (10μM) C B C A C C A

Among them, the inhibition rate over 75% was marked as A, 50%-75% was marked as B, 25%-50% was marked as C, and less than 25% was marked as D.

As can be seen from Table 1, the oseltamivir analogs containing pyridine fragments of the present invention have different degrees of inhibitory effect on neuraminidase, wherein compound I-4 exhibits strong neuraminidase inhibitory activity, and has a certain degree of inhibitory effect on neuraminidase. potential application value.

Further, the anti-influenza virus activity of the compound at the cellular level was tested, and MDCK cells infected with A/LiaoNing-ZhenXing/1109/2010 (H1N1) influenza virus (oseltamivir-resistant) were selected, wherein the EC of compound I-4 ₅₀ was 14.31 μM, which was better than 67.49 μM of OC, indicating that compound I-4 exhibited a therapeutic advantage on oseltamivir-resistant influenza virus strains.

Claims (10)

1. an oseltamivir analogue containing a pyridine fragment or a pharmaceutically acceptable salt or isomer thereof, characterized in that, having the general structural formula shown in formula I: Wherein, R ₁ , R ₂ and R ₃ are independently selected from hydrogen, halogen, methyl, hydroxyl, methoxy, nitro or amino. 2. The oseltamivir analog containing a pyridine fragment according to claim 1 or a pharmaceutically acceptable salt or isomer thereof, characterized in that it has the structural formula shown in formula I-1: 3. The oseltamivir analog containing a pyridine fragment according to claim 1 or a pharmaceutically acceptable salt or isomer thereof, characterized in that it has the structural formula shown in formula I-2: 4. The oseltamivir analog containing a pyridine fragment according to claim 1 or a pharmaceutically acceptable salt or isomer thereof, characterized in that it has the structural formula shown in formula I-3: 5. The oseltamivir analog containing a pyridine fragment according to claim 1 or a pharmaceutically acceptable salt or isomer thereof, characterized in that it has the structural formula shown in formula I-4: 6. The oseltamivir analog containing a pyridine fragment according to claim 1 or a pharmaceutically acceptable salt or isomer thereof, characterized in that it has the structural formula shown in formula I-5: 7. The oseltamivir analog containing a pyridine fragment according to claim 1 or a pharmaceutically acceptable salt or isomer thereof, characterized in that it has the structural formula shown in formula I-6: 8. The oseltamivir analogue or a pharmaceutically acceptable salt or isomer thereof containing a pyridine fragment according to any one of claims 1-7, further comprising the described pyridine fragment A hydrate, solvate, polymorph, prodrug, enantiomer or racemic mixture of an oseltamivir analog. 9. The oseltamivir analog containing a pyridine fragment according to any one of claims 1-7 or a pharmaceutically acceptable salt or isomer thereof is used in the preparation of neuraminidase inhibitors and/or in the preparation of therapeutic and and/or use in medicines for preventing and/or delaying/and/or adjuvant treatment of diseases caused by influenza virus. 10. A pharmaceutical composition, characterized in that it comprises a pyridine fragment-containing oseltamivir analog or a pharmaceutically acceptable salt or isomer or a hydrate, solvate, polymorph, pro- drug, enantiomeric or racemic mixture, and at least one pharmaceutically acceptable excipient.