Aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor and its preparation method and application
By introducing aromatic fused ring groups and optimizing structures into oxadiazole acetamide compounds, an efficient neuraminidase inhibitor was developed, which solved the problems of anti-influenza drug resistance and high production costs, and achieved the Lower IC50 value and easy synthesis process.
Patent Information
- Application Number
- CN202310003631.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-01-03
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2043-01-03
AI Technical Summary
Existing anti-influenza drugs have drug resistance problems, expensive production raw materials and complex synthesis processes, making it difficult to develop novel and efficient neuraminidase inhibitors.
An oxadiazole acetamide neuraminidase inhibitor containing aromatic condensed ring was designed. By introducing aromatic condensed ring groups such as naphthalene ring and quinoline ring, the inhibitory activity is enhanced, and molecular docking is used. and molecular dynamics simulation technology optimizes the structure of the compound and simplifies the synthesis method to suit large-scale production.
The inhibitor performed excellently in terms of IC50 values, as low as 0.14 μM, and has more inhibitory activity than the prior art. The simplified synthesis method is suitable for large-scale production, overcoming the problems of drug resistance and production costs.
Smart Images
Figure CN116120255B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of biomedicine technology, and in particular to an aromatic condensed ring-containing oxadiazole acetamide neuraminidase inhibitor, and a preparation method and application thereof. Background Art
[0002] Neuraminidase is a glycoprotein distributed on the influenza virus envelope, which can help mature influenza viruses to break away from the original host cells to infect new cells. Therefore, neuraminidase is one of the important targets for the development of anti-influenza drugs. At present, there are only 6 anti-influenza drugs approved by the US FDA, including 2 M2 proton channel inhibitors (amantadine and rimantadine), 3 neuraminidase inhibitors (zanamivir, oseltamivir and peramivir) and 1 RNA-dependent RNA polymerase inhibitor (sofruza). Anti-influenza drugs developed with neuraminidase as the target can be divided into the following categories according to their structure: cyclohexene, pyran, pyrrolidine, benzoic acid derivatives and natural products. The most widely used anti-influenza drug is Tamiflu, but with the widespread use of drugs, influenza virus resistance to Tamiflu has also emerged, and the raw materials for the production of Tamiflu are extremely expensive and the synthesis process is complicated. Therefore, it is urgent to develop an inhibitor of neuraminidase with a new structure and better inhibitory effect.
[0003] Studies have shown that there are two active cavities near the active site of neuraminidase, named 150-cavity and 430-cavity. These two active cavities are directly connected to the active site and are large in size, which provides new research ideas for the design of neuraminidase inhibitors.
[0004] Chinese patent ZL202110724363.X discloses a 1,3,4-oxadiazole neuraminidase inhibitor and its preparation method and application. Experiments have shown that it has good neuraminidase inhibitory activity and can be used to prepare drugs that inhibit neuraminidase activity. However, it is still necessary to develop more inhibitors with higher activity. Summary of the invention
[0005] The purpose of the present invention is to overcome the problems of drug resistance, complex synthesis process, expensive raw materials and the like in the above-mentioned prior art, and to provide a compound with novel structure and excellent neuraminidase inhibitory activity.
[0006] The purpose of the present invention can be achieved by the following technical solutions:
[0007] An aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor having a structure shown in Formula V or Formula VI:
[0008]
[0009] Wherein, R is selected from any one of the following structural formulas:
[0010]
[0011]
[0012] In the above structural formulas It means that the R group is connected to the amino group in the amide.
[0013] Further, the R is Any one of .
[0014] Furthermore, the inhibitor has one of the following chemical structural formulas:
[0015]
[0016] A method for preparing the above-mentioned oxadiazole acetamide neuraminidase inhibitor containing an aromatic fused ring, the method comprising the following steps:
[0017] (1) subjecting substituted aniline and chloroacetyl chloride to a nucleophilic substitution reaction under the catalysis of triethylamine to obtain an intermediate of formula II;
[0018] (2) taking the ethyl ester substituted compound and hydrazine hydrate in ethanol to undergo nucleophilic substitution to obtain an intermediate of formula III (1) or formula III (2);
[0019] (3) taking the intermediate of formula III (1) or formula III (2) and carbon disulfide, and reacting them in ethanol under an alkaline environment of potassium hydroxide to obtain the intermediate of formula IV (1) or formula IV (2);
[0020] (4) Take the intermediate of formula II and the intermediate of formula IV (1) or formula IV (2), dissolve anhydrous potassium carbonate in an organic solvent, react under the catalysis of potassium iodide, and then undergo substitution reaction to obtain the final product of formula V or formula VI, that is, an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, as shown in the following figure;
[0021]
[0022] Furthermore, in step (1), triethylamine is used as a catalyst, and substituted aniline and chloroacetyl chloride are reacted in an organic solvent of dichloromethane. The reaction system is placed at a temperature of 0-20°C, preferably 15°C, and the reaction time is 8-24h, preferably 24h. The post-treatment process is specifically as follows: after the reaction is completed, the reaction is washed with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated brine in sequence, the organic phase is dried with anhydrous sodium sulfate, and the solvent is removed in vacuo to obtain an intermediate of formula II, wherein the added amount ratio of the substituted aniline, chloroacetyl chloride, triethylamine and organic solvent is (3-8) mmol: (3-8) mmol: (3-8) mmol: (10-40) ml, preferably 5 mmol: 5 mmol: 5 mmol: 30 mL.
[0023] Furthermore, in step (2), the temperature of nucleophilic substitution is 60-85°C, preferably 80°C. The reaction time is 16-24h, preferably 18h. The reaction system is taken out, concentrated, cooled, and the intermediate of formula III (1) or formula III (2) is precipitated. The addition ratio of the ethyl ester substituted compound, hydrazine hydrate, and ethanol is (3-8) mmol: (6-16) mmol: (10-40) ml, preferably 5 mmol: 10 mmol: 25 mL.
[0024] Furthermore, in step (3), the reaction system is placed at a temperature of 25-100°C, preferably 80°C, and the reaction time is 14-48h, preferably 24h. The post-treatment process is specifically as follows: take out the reaction system for cooling: pour the reaction solution into ice water, adjust the acid to pH = 2.5-3.5 with dilute hydrochloric acid, wait for the solid to completely precipitate, filter, wash the filter cake with ice water, and then dry the filter cake at room temperature, and finally recrystallize with ethanol to obtain the intermediate of formula IV (1) or formula IV (2). The addition ratio of the intermediate of formula III (1) or formula III (2) to carbon disulfide is 1:2.
[0025] Further, in step (4), the organic solvent is acetone, acetonitrile or DMF, preferably acetone. The reaction system is placed in an oil bath for heating, the reaction temperature is 15-25°C, preferably 20°C, and the reaction time is 8-24h, preferably 24h. The post-treatment process is specifically: take out the reaction system for cooling, filter and take the mother liquor under normal pressure, rotary evaporate, mix the sample, and recrystallize with methanol to obtain the inhibitor shown in formula V or formula VI. The addition ratio of the intermediate of formula II, the intermediate of formula IV (1) or formula IV (2), anhydrous potassium carbonate, potassium iodide and the organic solvent is (1-1.5) mmol: (1-1.5) mmol: (1-1.5) mmol: (0.1-1) mmol: (10-20) ml, preferably 1.2 mmol: 1 mmol: 1 mmol: 0.1 mmol: 15 ml.
[0026] An application of the above-mentioned oxadiazole acetamide neuraminidase inhibitor containing an aromatic fused ring, wherein the inhibitor is applied to the preparation of a drug for inhibiting the activity of neuraminidase.
[0027] Furthermore, the inhibitory activity of this series of inhibitors against neuraminidase is as low as IC 50 =0.14 μM, lower than the IC of the positive control OSC 50 The value was low (0.31 μM), showing excellent neuraminidase inhibitory activity.
[0028] Compared with the prior art, the present invention has the following beneficial effects:
[0029] 1. The compounds of the present invention are further studied on the basis of the existing 1,3,4-oxadiazole neuraminidase inhibitor preparation technology. The structure retains the structure of the 1,3,4-oxadiazole ring, and introduces aromatic condensed ring groups such as a naphthalene ring and a quinoline ring. The aromatic condensed ring can well occupy the active cavity, so that the 1,3,4-oxadiazole ring is better combined with the active site, and by introducing a negatively charged substituted benzene ring, it extends into the 430-cavity or the 150-cavity, thereby enhancing the inhibitory activity of the compound.
[0030] 2. The present invention further optimized the structure of the lead compound ZINC13401480 by using molecular docking and molecular dynamics simulation technology, and designed and synthesized 10 new oxadiazole acetamide inhibitors containing aromatic fused rings. The new inhibitors not only have lower binding energy, but also can occupy the 150-cavity or 430-cavity while occupying the active site, in order to obtain neuraminidase inhibitors with better performance.
[0031] 3. IC of the compound of the present invention N-(4-fluorobenzyl)-2-((5-((naphthalen-2-yloxy)methyl)-1,3,4-oxadiazol-2-yl)thio)acetamide 50 The value was 0.14uM, which was similar to the positive control OSC IC 50 The ratio of the values is 0.45, and the relative activity is higher than the IC of 6d with the best activity in Chinese patent 202110724363.X and OSC. 50 The ratio of 0.33 is even better. Therefore, the aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitors of the present invention can be used to prepare drugs for inhibiting neuraminidase activity.
[0032] 4. The synthesis method is simple. Recrystallization is used in step 4 to replace column chromatography, which is easier to operate and more suitable for mass production. DETAILED DESCRIPTION
[0033] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.
[0034] An aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, and a preparation method and application thereof. The formula of the preparation method is as follows:
[0035]
[0036] The specific steps include:
[0037] (1) subjecting substituted aniline and chloroacetyl chloride to a nucleophilic substitution reaction under the catalysis of triethylamine to obtain an intermediate of formula II;
[0038] (2) Take the ethyl ester substituted compound and hydrazine hydrate in ethanol and perform nucleophilic substitution to obtain formula III (1) or formula III
[0039] (2) Intermediates;
[0040] (3) taking the intermediate of formula III (1) or formula III (2) and carbon disulfide, and reacting them in ethanol under an alkaline environment of potassium hydroxide to obtain the intermediate of formula IV (1) or formula IV (2);
[0041] (4) The intermediate of formula II and the intermediate of formula IV (1) or formula IV (2) are dissolved in an organic solvent, reacted under the catalysis of potassium iodide, and then subjected to substitution reaction to obtain the final product of formula V or formula VI.
[0042] Furthermore, in step (1), triethylamine is used as a catalyst, and substituted aniline and chloroacetyl chloride are reacted in an organic solvent of dichloromethane. The reaction system is placed at a temperature of 0-20°C, preferably 15°C, and the reaction time is 8-24h, preferably 24h. The post-treatment process is specifically as follows: after the reaction is completed, the reaction is washed with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated brine in sequence, the organic phase is dried with anhydrous sodium sulfate, and the solvent is removed in vacuo to obtain an intermediate of formula II, wherein the added amount ratio of the substituted aniline, chloroacetyl chloride, triethylamine and organic solvent is (3-8) mmol: (3-8) mmol: (3-8) mmol: (10-40) ml, preferably 5 mmol: 5 mmol: 5 mmol: 30 mL.
[0043] Furthermore, in step (2), the temperature of nucleophilic substitution is 60-85°C, preferably 80°C. The reaction time is 16-24h, preferably 18h. The reaction system is taken out, concentrated, and cooled to precipitate the intermediate of formula III (1) or formula III (2). The addition ratio of the ethyl ester substituted compound, hydrazine hydrate, and ethanol is: 5mmol:10mmol:25mL.
[0044] Furthermore, in step (3), the reaction system is placed at a temperature of 25-100°C, preferably 80°C, and the reaction time is 14-48h, preferably 24h. The post-treatment process is specifically as follows: take out the reaction system for cooling: pour the reaction solution into ice water, adjust the acid to pH = 2.5-3.5 with dilute hydrochloric acid, wait for the solid to completely precipitate, filter, wash the filter cake with ice water, and then dry the filter cake at room temperature, and finally recrystallize with ethanol to obtain the intermediate of formula IV (1) or formula IV (2). The addition ratio of the intermediate of formula III (1) or formula III (2) to carbon disulfide is 1:2.
[0045] Furthermore, in step (4), the organic solvent is acetone, acetonitrile or DMF, preferably acetone. The reaction system is placed in an oil bath for heating, the reaction temperature is 15-25°C, preferably 20°C, and the reaction time is 8-24h, preferably 24h. The post-treatment process is specifically as follows: taking out the reaction system for cooling, filtering the mother liquor under normal pressure, rotary evaporation, mixing the sample, and recrystallizing with methanol to obtain the inhibitor shown in Formula V or Formula VI. The addition ratio of the intermediate of Formula II, the intermediate of Formula IV (1) or Formula IV (2), anhydrous potassium carbonate, potassium iodide and the organic solvent is (1-1.5) mmol: (1-1.5) mmol: (1-1.5) mmol: (0.1-1) mmol: (10-20) ml, preferably 1.2 mmol: 1 mmol: 1 mmol: 0.1 mmol: 15 ml. The obtained aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor has the structure shown in Formula V or VI:
[0046]
[0047] R is selected from any one of the following structural formulas:
[0048]
[0049] Preferably, R is Any of these 5 structures.
[0050] The inhibitor can be used in the preparation of drugs capable of inhibiting neuraminidase activity.
[0051] Example 1
[0052] A method for preparing an oxadiazole acetamide neuraminidase inhibitor containing an aromatic fused ring, the structural formula of which is shown below:
[0053]
[0054] The specific synthesis steps are as follows:
[0055] (1) Accurately weigh 0.63 g (5 mmol) of (4-fluorophenyl)methylamine and 0.51 g (5 mmol) of triethylamine in a 250 mL round-bottom flask, pour in 30 mL of dichloromethane, protect with nitrogen, and stir in an ice bath. Then, add 0.37 mL (5 mmol) of chloroacetyl chloride dropwise with a 1 mL disposable syringe. After the addition is complete, stir and react at 15°C for 24 hours. After the reaction is completed, wash with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated brine in sequence, dry the organic phase with anhydrous sodium sulfate, and remove the solvent in vacuo to obtain the intermediate of formula II.
[0056] (2) Accurately weigh 1.15 g (5 mmol) of ethyl 2-(naphthalene-2-oxy)acetate and excess hydrazine hydrate in a 250 mL round-bottom flask, add 50 mL of ethanol, and reflux at 80° C. for 24 h. After the system is cooled to room temperature, concentrate to precipitate intermediate III (1).
[0057] (3) Accurately weigh 1.08 g (5 mmol) of the intermediate III (1) and 0.28 g (5 mmol) of potassium hydroxide into a 250 mL round-bottom flask, add 50 mL of ethanol and 10 mL of water, stir and dissolve at room temperature, and after the solid is completely dissolved, take 0.76 g (10 mmol) of carbon disulfide and dilute it with 50 mL of ethanol, slowly add it to the system with a constant pressure dropping funnel, and react at 85° C. for 24 hours. After the reaction is completed, take out the reaction system for cooling, pour the reaction solution into ice water, adjust the acidity to pH=3 with dilute hydrochloric acid, wait until the solid is completely precipitated, filter, wash the filter cake with ice water, and then dry the filter cake at room temperature, and then recrystallize it with ethanol to obtain the intermediate of formula IV (1).
[0058] (4) Accurately weigh 0.24 g (1.2 mmol) of the intermediate of formula II obtained in step (1), 0.26 g (1 mmol) of the intermediate of formula IV (1) obtained in step (3), 0.138 g (1 mmol) of anhydrous potassium carbonate, and 0.017 g (0.1 mmol) of potassium iodide into a 50 mL round-bottom flask, add 20 mL of acetone, place in a constant temperature oil bath and heat with stirring at 20° C. to react for 12 h, take out and cool the reaction solution, take out the reaction system and cool it, filter out the mother liquor under normal pressure, rotary evaporate, mix the sample, and recrystallize to obtain the inhibitor of the above structural formula.
[0059] The prepared inhibitor was tested for its neuraminidase activity inhibition:
[0060] 1. Experimental instruments and materials
[0061] Multifunctional fluorescence microplate reader, model SP-Max 3500FL, Shanghai Shanpu Biotechnology Co., Ltd.;
[0062] Clean bench;
[0063] Bond A3Pipette manual single-channel adjustable pipette, 0.5-10μL, 10-100μL, 100-1000μL Titan Technology;
[0064] 96-well plate (black), sterilized, Corning;
[0065] H5N1 neuraminidase was purchased from Beijing Sino Biological Technology Co., Ltd.; the fluorescent substrate 2'-(4-methylumbelliferyl)-α-D-acetylneuraminic acid sodium hydrate (4-MUNANA) (Sigma, M8639) used in the enzyme inhibition experiment was purchased from Sigma; 2-(N-morpholino)ethanesulfonic acid (MES), calcium chloride, sodium hydroxide, and anhydrous ethanol were purchased from Titan Technology.
[0066] Positive control drug, Oseltamivir carboxlate (OSC), Shanghai Hekang Biotechnology Co., Ltd.
[0067] 2. Experimental methods
[0068] The positive control drug and the target compound (i.e., N-(4-fluorobenzyl)-2-((5-((naphthalene-2-yloxy)methyl)-1,3,4-oxadiazol-2-yl)thio)acetamide prepared in Example 1) were dissolved in DMSO, and the initial concentration was prepared to be 1000 μM / L, which was diluted into 7 concentration gradients in multiple ratios, namely 1000 μM / L, 200 μM / L, 40 μM / LL, 8 μM / L, 1.6 μM / L, 0.32 μM / L, and 0.064 μM / L, and three groups were prepared in each concentration gradient;
[0069] 2.1 Sample test preparation
[0070] a. Add 70 μL of buffer (33 mM MES, 4 mM CaCl2) to each well in a 96-well ELISA plate;
[0071] b. Add 10 μL of neuraminidase to each well;
[0072] c. Add 10 μL of the prepared neuraminidase inhibitor sample or positive control drug sample to each well, and set up three groups of blank test controls;
[0073] d. Add 10 μL of neuraminidase substrate (100 μM / L 4-MUNANA) to each well.
[0074] 2.2 Detection
[0075] a. Place the 96-well plate in a multifunctional fluorescence microplate reader and shake to mix for 1 minute;
[0076] b. Set the temperature to 37 degrees Celsius and incubate for 5 minutes to allow the neuraminidase and the sample to be tested to fully mix and interact;
[0077] c. Take out the 96-well plate and add 10 μL of neuraminidase fluorescent substrate to each well;
[0078] d. Place the sample in the multifunctional fluorescence microplate reader again and shake and mix for 1 minute;
[0079] e. Incubate at 37 degrees Celsius for 30 minutes, take out, add 150 μL of stop solution (14 mM / L NaOH in 83% ethanol aqueous solution) to each well, place in the multifunctional fluorescence microplate reader again, shake and mix for 1 minute, set the excitation wavelength to 355 nm, and the emission wavelength to 460 nm. After the incubation, start the fluorescence intensity (RFU) measurement;
[0080] f. Repeat the above steps and perform 3 sets of parallel experiments.
[0081] Note: The first well in the 96-well plate is used as a blank group. No test sample is added, but 10 μl of DMSO solution is added.
[0082] Calculate the average inhibition rate of samples at each gradient concentration in each parallel experiment, and then fit the corresponding IC through Origin. 50 value.
[0083] 2.3 Experimental Results
[0084] Specifically, it is N-(4-fluorobenzyl)-2-((5-((naphthalen-2-yloxy)methyl)-1,3,4-oxadiazol-2-yl)thio)acetamide, which is a white solid with a yield of 88%.
[0085] 1 H NMR (500MHz, DMSO-d6) δ8.84(t,J=5.9Hz,1H),7.87(t,J=7.8Hz,2H),7.82(d,J=8.2Hz,1H),7.54–7.47(m,2H),7 .40(t,J=7.5Hz,1H),7.33–7.25(m,3H),7.12(t,J=8.7Hz,2H),5.51(s,2H),4.30(d,J=5.8Hz,2H),4.16(s,2H). 13C NMR (125 MHz, DMSO-d6) δ 166.44, 165.16, 165.12, 165.08, 164.05, 164.01, 155.64, 134.43, 130.37, 129.48, 129.02, 127.98, 126.48, 119.37, 118.13, 116.48, 114.94, 108.87, 59.95, 58.76, 36.16. Its IC 50 The value is 0.14 μM, and the IC of the positive control drug 50 The value is 0.31 μM.
[0086] The positive control drug and the target compound were prepared into a mixed solution with an initial concentration of 1000 μM / L using DMSO solution, and then the two mixed solutions were diluted into 6 concentration gradients in multiple ratios, namely 200 μM / L, 40 μM / L, 8 μM / L, 1.6 μM / L, 0.32 μM / L, and 0.064 μM / L, and three groups were prepared for each concentration gradient. 70 μL of neuraminidase buffer, 10 μL of neuraminidase, and the positive control drug samples of each gradient concentration to be tested were added to the 96-well black fluorescent ELISA plate, and three groups of blank test controls were set up at the same time. Mix by shaking for 1 minute in a multifunctional fluorescence microplate reader, and incubate at 37°C for 5 minutes; take out the 96-well microplate, add 10 μL of neuraminidase substrate to each well, shake for 1 minute to mix, incubate at 37°C for 30 minutes, take out, add 150 μL of stop solution (14 mM / L NaOH in 83% ethanol aqueous solution) to each well, place in a multifunctional fluorescence microplate reader again, shake and mix for 1 minute, set the excitation wavelength to 355 nm, set the emission wavelength to 460 nm, and start the fluorescence intensity (RFU) measurement after the incubation. Perform three experiments in parallel. Calculate the average inhibition rate of the samples at each gradient concentration in each parallel experiment, and then fit the corresponding IC through Origin. 50 The inhibition rate of each sample was calculated using the value, and then the corresponding IC was fitted using Origin. 50 value.
[0087] Example 2
[0088] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, wherein 2-(3-fluorophenyl)ethane-1-amine is used as a raw material in step 1, and then the inhibitor is prepared by a method similar to that in Example 1. The obtained inhibitor has the following structural formula:
[0089] N-(3-Fluorophenethyl)-2-((5-((naphthalene-2-oxy)methyl)-1,3,4-oxadiazol-2-yl)thio)acetamide
[0090]
[0091] The obtained white solid product was tested by the same method as in Example 1: yield 78%, IC 50 The value is 1.16μM.
[0092] 1 H NMR(500MHz,DMSO-d6)δ8.41(s,1H),7.92–7.76(m,3H),7.49(m,J=12.1Hz,2H),7.38(t,J=7.5Hz,1H),7.27(dd, J=17.6,8.2Hz,2H),7.03(q,J=11.0,10.4Hz,3H),5.50(s,2H),4.06(s,2H),3.34(d,J=6.6Hz,2H),2.74(t,J=6. 8Hz,2H).13CNMR(125MHz,DMSO-d6)δ166.36,165.14,163.98,155.62,142.68,134.43,131.25,130.76,129.89, 129.52,127.98,126.65,125.30,124.03,119.34,118.05,108.96,107.63,107.52,61.02,60.00,58.78,36.04.
[0093] Example 3
[0094] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, wherein 3,4-dichlorophenylmethylamine is used as a raw material in step 1, and then the inhibitor is prepared by a method similar to that in Example 1. The obtained inhibitor has the following structural formula:
[0095] N-(3,4-dichlorobenzyl)-2-(5-naphthalen-2-yloxymethyl)-1,3,4-oxadiazole-2-thio)acetamide:
[0096]
[0097] The obtained white solid product was tested by the same method as in Example 1: yield 80%, IC 50 The value is 0.86μM.
[0098] 1H NMR(500MHz,DMSO-d6)δ8.84(t,J=6.0Hz,1H),7.84–7.73(m,3H),7.45(dq,J=14.9,8.0Hz,4H) ,7.33(t,J=7.5Hz,1H),7.20(d,J=8.2Hz,2H),5.45(s,2H),4.26(d,J=5.9Hz,2H),4.12(s,2H). 13 C NMR(125MHz,DMSO-d6)δ165.11,164.09,164.05,155.64,140.77,134.43,131.53,130.20,129.49 ,128.67,127.81,125.35,124.02,122.39,119.37,118.12,108.88,107.65,61.14,59.94,36.06.
[0099] Example 4
[0100] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, wherein 2-(3-methoxyphenyl)ethane-1-amine is used as a raw material in step 1, and then the inhibitor is prepared by a method similar to that in Example 1. The obtained inhibitor has the following structural formula:
[0101] N-(3-methoxyphenethyl)-2-(5-naphthalen-2-yloxymethyl)-1,3,4-oxadiazol-2-ylthio)acetamide:
[0102]
[0103] The obtained white solid product was tested by the same method as in Example 1: yield 86%, IC 50 The value is 1.62μM.
[0104] 1 H NMR(500MHz,DMSO-d6)δ9.21(t,J=5.8Hz,1H),7.69(m,J=8.2Hz,7H),6.99(m,J=7.5Hz,4H) ,5.47(q,J=6.9Hz,2H),3.97(t,J=7.1Hz,2H), 3.35(m,J=7.1Hz,2H),2.74(t,J=7.1Hz,2H). 13C NMR (125MHz, DMSO-d6) δ171.60,163.80,162.78,161.60,160.14,154.62,141.45,133.81,131.63,129.85,12 8.93,127.83,127.41,126.34,125.71,124.15,115.23,114.43,114.16,110.12,59.46,41.30,34.82,34.31.
[0105] Example 5
[0106] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, wherein 2-(3,4-dimethoxyphenyl)ethane-1-amine is used as a raw material in step 1, and then the inhibitor is prepared by a method similar to that in Example 1. The obtained inhibitor has the following structural formula:
[0107] N-(3,4-dimethoxyphenethyl)-2-(5-naphthalen-2-yloxymethyl)-1,3,4-oxadiazole-2-thio)acetamide:
[0108]
[0109] The obtained white solid product was tested by the same method as in Example 1: yield 87%, IC 50 The value is 2.82μM.
[0110] 1 H NMR (500MHz, DMSO-d6) δ9.01(d,J=4.1Hz,1H),8.63(s,1H),8.55(d,J=8.2Hz,1H),8.42(s,1H),8.26(d,J=8.9Hz,1H),8.18(d,J=8.8Hz,1H),7.64(d d,J=8.3,4.2Hz,1H),6.81(d,J=8.2Hz,2H),6.70(d,J=8.1Hz,1H),4.15(s ,2H),3.70(d,J=23.7Hz,6H),3.34(q,J=6.6Hz,2H),2.67(t,J=7.2Hz,2H). 13C NMR(125MHz,DMSO-d6)δ166.36,165.29,164.40,149.11,147.77,132.14,131.47,130.16,128.13,126.9 8,126.97,123.79,122.46,121.34,121.26,112.96,112.34,111.70,56.42,55.27,54.21,36.34,35.20.
[0111] Example 6
[0112] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, wherein 2-(3-methoxyphenyl)ethane-1-amine is used as a raw material in step 1, quinoline-6-carboxylic acid methyl ester is used as a raw material in step 2, and then the inhibitor is prepared by a method similar to that of Example 1. The obtained inhibitor has the following structural formula:
[0113] N-(3-methoxyphenethyl)-2-(5-quinolin-6-yl)-1,3,4-oxadiazol-2-ylthioacetamide:
[0114]
[0115] The yellow solid product obtained was tested in the same manner as in Example 1: yield 89%, IC 50 The value is 1.49 μM.
[0116] 1 H NMR(500MHz,DMSO-d6)δ8.99(d,J=2.7Hz,1H),8.60(s,J=2.3Hz,1H),8.52(d ,J=8.1Hz,2H),8.23(d,J=8.7Hz,1H),8.15(d,J=8.8Hz,1H),7.62(dd,J=8.4 ,4.3Hz,1H),7.15(t,J=7.8Hz,1H),6.76(d,J=7.3Hz,2H),6.72(d,J=6.6Hz, 1H), 4.16 (s, 2H), 3.70 (s, 3H), 3.35 (q, J = 6.7Hz, 2H), 2.72 (t, J = 7.4Hz, 2H). 13CNMR(125MHz,DMSO-d6)166.45,165.43,163.83,159.84,159.56,153.88,153.62,149.01,148.75,141.3 6,141.29,136.81,131.42,130.39,130.10,129.78,120.96,115.25,111.47,56.27,54.44,53.59,36.34.
[0117] Example 7
[0118] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, the structural formula of which is as follows: in step 1, 2-(3,4-dimethoxyphenyl)ethane-1-amine is used as a raw material, and in step 2, quinoline-6-carboxylic acid methyl ester is used as a raw material, and then the inhibitor is prepared by a method similar to that of Example 1. The structural formula of the obtained inhibitor is as follows:
[0119] N-(3,4-dimethoxyphenethyl)-2-(5-quinolin-6-yl)-1,3,4-oxadiazole-2-thio)acetamide:
[0120]
[0121] The obtained white solid product was tested by the same method as in Example 1: yield 87%, IC 50 The value is 2.96μM.
[0122] 1 H NMR (500MHz, DMSO-d6) δ9.01(d,J=4.1Hz,1H),8.63(s,1H),8.55(d,J=8.2Hz,1H),8.42(s,1H),8.26(d,J=8.9Hz,1H),8.18(d,J=8.8Hz,1H),7.64(d d,J=8.3,4.2Hz,1H),6.81(d,J=8.2Hz,2H),6.70(d,J=8.1Hz,1H),4.15(s ,2H),3.70(d,J=23.7Hz,6H),3.34(q,J=6.6Hz,2H),2.67(t,J=7.2Hz,2H). 13C NMR(125MHz,DMSO-d6)δ166.36,165.29,164.40,149.11,147.77,132.14,131.47,130.16,128.13,126.9 8,126.97,123.79,122.46,121.34,121.26,112.96,112.34,111.70,56.42,55.27,54.21,36.34,35.20.
[0123] Example 8
[0124] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, the structural formula of which is as follows: in step 2, quinoline-6-carboxylic acid methyl ester is used as a raw material, and then the inhibitor is prepared by a method similar to that in Example 1. The structural formula of the obtained inhibitor is as follows:
[0125] N-(4-fluorobenzyl)-2-((5-(quinolin-6-yl)-1,3,4-oxadiazol-2-yl)thio)acetamide:
[0126]
[0127] The yellow solid product obtained was tested in the same manner as in Example 1: yield 90%, IC 50 The value is 1.75 μM.
[0128] 1 H NMR (500MHz, DMSO-d6) δ9.00(d,J=2.3Hz,1H),8.90(t,1H),8.58(d,J=1.9Hz,1H),8.51(d,J=8.2Hz,1H),8.23 (d,J=8.8Hz,1H),8.15(d,J=8.8Hz,1H),7.63(dd,J=8.3,4.2Hz,1H),7.34–7.28(m,2H),7.07(t,J=8.7Hz,2H) ,4.33(d,J=5.8Hz,2H),4.23(s,2H).13CNMR(125MHz,DMSO-d6)δ166.62,165.29,164.33,162.57,153.72,149 .00,138.08,136.75,135.46,131.43,127.30,126.05,122.42,121.28,121.21,116.19,114.86,37.38,36.24.
[0129] Example 9
[0130] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, the structural formula of which is as follows: in step 1, 3,4-dichlorophenylmethylamine is used as a raw material, and in step 2, quinoline-6-carboxylic acid methyl ester is used as a raw material, and then the inhibitor is prepared by a method similar to that in Example 1. The obtained inhibitor has the following structural formula:
[0131] N-(3,4-dichlorobenzyl)-2-((5-(quinolin-6-yl)-1,3,4-oxadiazol-2-yl)thio)acetamide:
[0132]
[0133] The obtained grey solid product was tested in the same manner as in Example 1: yield 88%, IC 50 The value is 0.65 μM.
[0134] 1 H NMR (500MHz, DMSO-d6) δ9.04–8.94(m,2H),8.58(s,1H),8.51(d,J=8.2Hz,1H),8.22(d,J=8.8Hz,1H),8.15(d,J=8. 8Hz,1H),7.63(dd,J=8.2,4.2Hz,1H),7.51–7.43(m,2H),7.25(d,J=8.2Hz,1H),4.34(d,J=5.9Hz,2H),4.24(s,2H). 13 C NMR(125MHz,DMSO-d6)δ166.96,166.93,165.29,164.34,164.29,153.67,149.04,140.65,138 .11,131.44,130.16,129.86,127.34,126.02,125.96,123.82,123.75,121.26,121.19,36.09.
[0135] Example 10
[0136] A method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, wherein 2-(3-fluorophenyl)ethane-1-amine is used as a raw material in step 1, quinoline-6-carboxylic acid methyl ester is used as a raw material in step 2, and then the inhibitor is prepared by a method similar to that of Example 1. The obtained inhibitor has the following structural formula:
[0137] N-(3-fluorophenethyl)-2-((5-(quinolin-6-yl)-1,3,4-oxadiazol-2-yl)thio)acetamide:
[0138]
[0139] The obtained grey solid product was tested by the same method as in Example 1: yield 89%, IC 50 The value is 10.70 μM.
[0140] 1 H NMR (500MHz, DMSO-d6) δ8.99(dd,J=4.2,1.8Hz,1H),8.60(s,1H),8.53(d,J=8.3Hz,1H),8.48(s,1H),8.24(d,J=8.7Hz,1H),8.16(d,J=8.9Hz,1H),7.6 2(dd,J=8.3,4.2Hz,1H),7.28(q,J=7.6Hz,1H),7.04(t,J=7.2Hz,2H),6.98 (t,J=8.7Hz,1H),4.15(s,2H),3.38(d,J=6.4Hz,2H),2.76(t,J=7.2Hz,2H). 13 C NMR(125MHz,DMSO-d6)δ166.47,165.25,164.37,153.71,148.98,142.62,142.57,138.06,13 1.44,131.16,130.13,129.94,128.24,127.37,122.42,121.30,121.23,37.45,36.31,35.16.
[0141] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.
Claims
1. An aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor, It is characterized in that The inhibitor has one of the following chemical formulas:
2. A method for preparing the aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor as claimed in claim 1, It is characterized in that The method comprises the following steps: (1) R-NH 2 , chloroacetyl chloride is reacted in dichloromethane solvent under the catalysis of triethylamine to obtain the intermediate of formula II through nucleophilic substitution reaction; (2) Ethyl ester substituted compound With hydrazine hydrate in ethanol to obtain the intermediate of formula III (1) or formula III (2); (3) taking the intermediate of formula III (1) or formula III (2) and carbon disulfide, and reacting them in ethanol under an alkaline environment of potassium hydroxide to obtain the intermediate of formula IV (1) or formula IV (2); (4) The intermediate of formula II and the intermediate of formula IV (1) or formula IV (2) are dissolved in an organic solvent with anhydrous potassium carbonate, and reacted under the catalysis of potassium iodide, and then subjected to a substitution reaction to obtain a final product of formula V or formula VI, i.e., the aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor according to claim 1, which is specifically as follows:
3. The method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor according to claim 2, It is characterized in that In step (1), the temperature of the nucleophilic substitution reaction is 0-20°C and the time is 8-24h. After the nucleophilic substitution reaction, post-treatment is performed by the following method: after the reaction is completed, washing with hydrochloric acid solution, saturated sodium bicarbonate solution and saturated brine in sequence, drying the organic phase with anhydrous sodium sulfate, and removing the solvent in vacuo to obtain the intermediate of formula II.
4. The method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor according to claim 2, It is characterized in that In step (2), the temperature of nucleophilic substitution is 60-85°C and the time is 16-24 hours. After the reaction, the reaction system is taken out, concentrated, and cooled to precipitate the intermediate of formula III (1) or formula III (2).
5. The method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor according to claim 2, It is characterized in that In step (3), the temperature of the cycloaddition reaction is 25-80° C., and the time is 14-48 h. After the cycloaddition reaction, post-treatment is performed by the following method: the reaction system is taken out and cooled, and then the reaction solution is poured into ice water, and the pH is adjusted to 2.5-3.5 with dilute hydrochloric acid. After the solid is completely precipitated, filtering is performed, the filter cake is washed with ice water, and then the filter cake is dried at room temperature, and finally recrystallized with ethanol to obtain the intermediate of formula IV (1) or formula IV (2).
6. The method for preparing an aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor according to claim 2, It is characterized in that In step (4), the temperature of the substitution reaction is 15-25°C and the time is 6-12 hours. After the substitution reaction, post-treatment is performed by the following method: taking out the reaction system for cooling, filtering the mother liquor under normal pressure, rotary evaporation, mixing the sample, and recrystallization to obtain the inhibitor of formula V or formula VI.
7. Use of the aromatic fused ring-containing oxadiazole acetamide neuraminidase inhibitor as claimed in claim 1, It is characterized in that The inhibitor is used for preparing drugs for inhibiting neuraminidase activity.