Schiff base vanillin acetylcholin esterase inhibitor as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of biological medicine, and particularly relates to a Schiff base vanillin acetylcholin esterase inhibitor and a preparation method and application thereof, the Schiff base vanillin acetylcholin esterase inhibitor has a structure shown as a formula (I): # imgabs0 #, in the formula (I), R1 is phenyl connected with a substituent group, and R2 is a group containing carbonyl, sulfuryl or heterocyclic ring. Compared with the prior art, the invention provides the acetylcholin esterase inhibitor with a novel structure, and experiments show that the acetylcholin esterase inhibitor has good acetylcholin esterase inhibition activity and can be used for preparing medicines for inhibiting the acetylcholin esterase activity.

Description

Technical Field

[0001] The invention belongs to the technical field of biomedicine, and in particular relates to a Schiff base vanillin acetylcholinesterase inhibitor and a preparation method and application thereof. Background Art

[0002] Acetylcholinesterase is a key enzyme in biological nerve conduction. In cholinergic synapses, the enzyme can degrade acetylcholine, terminate the excitatory effect of neurotransmitters on the postsynaptic membrane, and ensure the normal transmission of nerve signals in the body. It has the activity of carboxypeptidase and aminopeptidase. Acetylcholinesterase participates in the development and maturation of cells and can promote neuron development and nerve regeneration.

[0003] Currently, acetylcholinesterase inhibitors such as donepezil, tacrine and rivastigmine are clinically used for the prevention and treatment of Alzheimer's disease. The most widely used acetylcholinesterase drug for Alzheimer's disease is donepezil. However, long-term use of these drugs can cause obvious adverse reactions, including nausea, diarrhea, insomnia, vomiting, muscle cramps, fatigue, lethargy and loss of appetite. Therefore, it is very necessary to find highly effective acetylcholinesterase inhibitors with fewer side effects for the treatment of Alzheimer's disease.

[0004] Patent application 202110728696.X discloses a 4,6-dihydroxy-2-phenylbenzofuran acetylcholinesterase inhibitor, which is prepared by a four-step reaction, and has two hydroxyl groups in the structure, and its structure is shown in formula (1). The 4,6-dihydroxy-2-phenylbenzofuran acetylcholinesterase inhibitor described in the invention has good acetylcholinesterase inhibitory activity, IC 50 The value was 0.086±0.01μM, which was very close to the positive control drug donepezil (IC 50 The value was 0.079±0.007μM).

[0005]

[0006] Patent application 202110895966.6 discloses a 3-((3,5-dimethoxybenzyl)amino)-8-methoxycoumarin acetylcholinesterase inhibitor and its preparation method and application. The 3-((3,5-dimethoxybenzyl)amino)-8-methoxycoumarin acetylcholinesterase inhibitor is a base with amino and methoxy groups combined with toluene with two methoxy groups on the skeleton of coumarin. The structure is shown in formula (2). Its IC 50 The value was 0.068±0.04μM, which was better than the positive control drug donepezil (IC 50 The value was 0.079±0.008μM).

[0007]

[0008] Although some compounds with good inhibitory effects on acetylcholinesterase activity have been disclosed, it is still necessary to study and develop acetylcholinesterase inhibitors of different structural types to suit different usage conditions. Summary of the invention

[0009] The purpose of the present invention is to provide a Schiff base vanillin acetylcholinesterase inhibitor and its preparation method and application in order to solve at least one of the above problems. This scheme proposes a novel acetylcholinesterase inhibitor, which has good acetylcholinesterase inhibitory activity as shown in experiments and can be used to prepare drugs for inhibiting acetylcholinesterase activity.

[0010] The purpose of the present invention is achieved through the following technical solutions:

[0011] The first aspect of the present invention discloses a Schiff base vanillin acetylcholinesterase inhibitor having a structure as shown in formula (I):

[0012]

[0013] In formula (I), R 1 is a phenyl group connected with a substituted group, R 2 is a group containing a carbonyl group, a sulfone group or a heterocyclic ring.

[0014] Preferably, the R 1 Selected from:

[0015]

[0016] One of them.

[0017] Preferably, the R 2 Selected from:

[0018]

[0019] One of them.

[0020] Preferably, the Schiff base vanillin acetylcholinesterase inhibitor is:

[0021] IC of the four structural formula compounds 50 The value is closer to 0.02±0.01μM.

[0022] Preferably, the Schiff base vanillin acetylcholinesterase inhibitor is:

[0023] The Schiff base vanillin acetylcholinesterase inhibitor under this structural formula has an IC 50 The value was 0.18±0.06μM, which showed excellent acetylcholinesterase inhibitory activity.

[0024] The second aspect of the present invention discloses a method for preparing the Schiff base vanillin acetylcholinesterase inhibitor as described above, comprising the following steps:

[0025] S1: mixing substituted aniline and chloroacetyl chloride and undergoing a nucleophilic substitution reaction to obtain a first intermediate;

[0026] S2: mixing the first intermediate with vanillin and causing a first reaction to obtain a second intermediate;

[0027] S3: The second intermediate is mixed with a substituted hydrazine and subjected to a second reaction to obtain the Schiff base vanillin acetylcholinesterase inhibitor.

[0028] Preferably, in step S1, the nucleophilic substitution reaction is carried out in dichloromethane, using DMF as a catalyst and anhydrous K 2 CO 3 As an acid binding agent; the molar ratio of substituted aniline to chloroacetyl chloride is 10-20:15-20; the reaction temperature is 0-5°C, and the reaction time is 6-8h.

[0029] Preferably, in step S2, the first reaction is carried out in acetone, using KI as a catalyst and using anhydrous K 2 CO 3 As an acid binding agent; the molar ratio of the first intermediate and vanillin is 10-20:10-20; the reaction temperature is 50-70°C, and the reaction time is 4-6h.

[0030] Preferably, in step S3, the second reaction is carried out in anhydrous ethanol, using acetic acid as a catalyst; the molar ratio of the second intermediate to the substituted hydrazine is 10-20:10-20; the reaction temperature is 50-65° C., and the reaction time is 4-6 hours.

[0031] The preparation process of Schiff base vanillin acetylcholinesterase inhibitors is shown in the following reaction formula:

[0032]

[0033] In the reaction formula, Formula II is the general structural formula of the first intermediate, and Formula III is the general structural formula of the second intermediate.

[0034] The third aspect of the present invention discloses a use of any of the above-mentioned Schiff base vanillin acetylcholinesterase inhibitors in the preparation of a drug for inhibiting the activity of acetylcholinesterase.

[0035] The present invention uses a receptor-based molecular docking virtual screening method to screen 800,000 compounds from the ZINC database and obtains a compound with theoretical acetylcholinesterase inhibitory activity. Then, the compound is modified to design a more reasonable compound, and 16 of the compounds are tested for acetylcholinesterase, with donepezil as a positive control. The IC 50 The value was 0.02±0.01 μM. The instrument used to test the positive control and the synthetic compound was the Spark multifunctional microplate reader from TECAN, Switzerland.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] Compared with the prior art, the present invention provides an acetylcholinesterase inhibitor with a new skeleton structure, a preparation method and an application thereof. The synthesis method of the acetylcholinesterase inhibitor is simple, the prepared inhibitor has good acetylcholinesterase inhibitory activity, has excellent acetylcholinesterase inhibitory effect, and can be used to prepare drugs for inhibiting acetylcholinesterase activity. DETAILED DESCRIPTION

[0038] The present invention is described in detail below with reference to specific embodiments, but this is by no means a limitation of the present invention.

[0039] In the following description, unless otherwise specified, the reagents used are commercially available products and the methods used are common knowledge in the art; matters not covered may adopt existing technologies.

[0040] A Schiff base vanillin acetylcholinesterase inhibitor having a structure as shown in formula (I):

[0041]

[0042] In formula (I):

[0043] R 1 Selected from:

[0044]

[0045] One of;

[0046] R 2 Selected from:

[0047]

[0048] One of them.

[0049] Preferably:

[0050]

[0051] Most preferably: Its IC 50 The value was 0.18±0.06μM, which showed excellent acetylcholinesterase inhibitory activity.

[0052] A method for preparing the Schiff base vanillin acetylcholinesterase inhibitor as described above comprises the following steps:

[0053] S1: mixing substituted aniline and chloroacetyl chloride and undergoing a nucleophilic substitution reaction to obtain a first intermediate;

[0054] S2: mixing the first intermediate with vanillin and causing a first reaction to obtain a second intermediate;

[0055] S3: The second intermediate is mixed with a substituted hydrazine and subjected to a second reaction to obtain the Schiff base vanillin acetylcholinesterase inhibitor.

[0056] As shown in the following reaction formula:

[0057]

[0058] In the reaction formula, Formula II is the general structural formula of the first intermediate, and Formula III is the general structural formula of the second intermediate.

[0059] The preparation method specifically comprises:

[0060] In step S1, the nucleophilic substitution reaction is carried out in dichloromethane, using DMF as a catalyst and anhydrous K 2 CO 3 As an acid-binding agent; the reaction temperature is 0 to 5°C, preferably 0°C, and the reaction time is 6 to 8h, preferably 6h; substituted aniline, chloroacetyl chloride, DMF, anhydrous K 2 CO 3 The addition ratio of the organic solvent is (10-20) mmoL: (15-20) mmoL: (1-4) mmoL: (20-40) mmoL:

[0061] (50~80)mL; preferably 10mmoL: 15mmoL: 2mmoL: 30mmoL: 60mL.

[0062] After the nucleophilic substitution reaction, post-treatment is performed to obtain the first intermediate: after the reaction is completed, the reaction solution is poured into 50 mL of distilled water, 10 mL of dichloromethane is added to extract the aqueous phase three times, the organic phases are combined, and the organic phases are washed with 0.5 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated brine in sequence, and the organic phase is dried with anhydrous sodium sulfate. The organic phase solution is subjected to reduced pressure rotary evaporation to form a solid, and ultrasonication is performed until the system is uniform and there are no large lumps.

[0063] In step S2, the first reaction is carried out in acetone, using KI as a catalyst and anhydrous K 2 CO 3 as an acid-binding agent; the reaction temperature is 50-70°C, preferably 55°C, and the reaction time is 4-6h, preferably 5h. First intermediate, vanillin, KI, anhydrous K 2 CO 3 The additive ratio to the organic solvent is (10-20) mmoL: (10-20) mmoL: (0.1-0.5) mmoL: (15-30) mmoL: (10-20) mL, preferably 10 mmoL: 10 mmoL: 0.2 mmoL: 15 mmoL: 15 mL.

[0064] The first reaction is post-processed to obtain the second intermediate: after the material conversion is complete, the temperature of the reaction system is lowered to room temperature for filtering. The filter cake is retained and washed with saturated brine to obtain a crude product, which is sampled and loaded onto a column. After column chromatography separation, it is dissolved in the eluent, and then vacuum-evaporated into a solid state. Ultrasonication is performed until the system is uniform and there are no large lumps, and then dried.

[0065] In step S3, the second reaction is carried out in anhydrous ethanol, using acetic acid as a catalyst; the reaction temperature is 50-65°C, preferably 50°C, and the reaction time is 4-6h, preferably 4h. The addition ratio of the second intermediate, substituted hydrazine, acetic acid and organic solvent is (10-20) mmoL: (10-20) mmoL:

[0066] (0.2~0.4)mL:(10~20)mL. Preferably:10mmoL:10mmoL:0.2mmoL:15mL.

[0067] The second reaction is post-processed to obtain a Schiff base vanillin acetylcholinesterase inhibitor: the reaction system is taken out for cooling, and after the reaction solution is cooled to room temperature, it is filtered with a glass suction funnel, the filtrate is poured in, and the filter cake is collected. A small amount of anhydrous ethanol is added to the reaction bottle for washing, and it is filtered again. The collected filter cake is washed with purified water, anhydrous ethanol, and saturated saline in turn, and finally the filter cake is dried.

[0068] The prepared inhibitor was tested for its acetylcholinesterase inhibitor activity, and the specific test method is as follows:

[0069] 1. Experimental instruments and materials

[0070] Multifunctional microplate reader, Spark model, TECAN, Switzerland;

[0071] Clean bench;

[0072] Bond A3 Pipette manual single-channel adjustable pipette, 0.5-10μL, 10-100μL, 100-1000μL, Titan Technology;

[0073] 96-well plate (white), sterile, Corning;

[0074] Acetylcholinesterase (AChE) was purchased from Shanghai Yien Chemical Technology Co., Ltd.; disodium hydrogen phosphate dodecahydrate, disodium hydrogen phosphate dihydrate, colorimetric agent 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) and acetylthiocholine iodide (ATCI) were purchased from Shanghai Titan Technology Co., Ltd.

[0075] The positive control drug, donepezil, was purchased from Shanghai Titan Technology Co., Ltd.

[0076] 2. Reagent Preparation

[0077] a. 0.1 mol / L, pH=7.60 phosphate buffer (PBS): Mix 0.1 mM sodium dihydrogen phosphate solution and 0.1 mM sodium dihydrogen phosphate solution, and adjust the solution pH to 7.60.

[0078] b. Substrate solution: First, dissolve 72 mg of ATCI in 10 mL of PBS, then take 0.1 mL and add 10 mL of PBS to dilute it to a 0.25 mM solution, which is ready for use.

[0079] c. Enzyme solution: Weigh 25 mg 200 U / g AChE and add it to 20 mL PBS buffer to prepare a stock solution with a concentration of 0.25 U / mL. It is ready for use and can be used immediately after preparation.

[0080] d. Color developer: weigh 99 mg DTNB and dissolve it in 10 mL DMSO. Take 0.1 mL and add it to 10 mL DMSO to make a 0.25 mM solution. It is ready for use.

[0081] e. Positive control and sample solutions: Donepezil and the synthetic compound were dissolved in DMSO, respectively, with an initial concentration of 1000 μmoL / L, and then diluted into seven concentration gradients in multiple ratios, namely 500 μmoL / L, 100 μmoL / L, 10 μmoL / L, 1 μmoL / L, 0.1 μmoL / L, 0.05 μmoL / L, and 0.005 μmoL / L. Three groups were prepared for each concentration gradient.

[0082] 3. Experimental Methods

[0083] All test compounds and positive controls were dissolved in DMSO and prepared into 8 different working concentrations. Subsequently, 40 μL of each concentration was added to a 96-well plate. The same volume of AChE solution (enzyme solution) was added to each well for pre-incubation at 37°C for 30 minutes. After pre-incubation, 40 μL of substrate solution was added, and finally 40 μL of PBS solution was added to the 96-well plate. At the same time, a sample background group A was established. 0 (without adding enzyme solution) and add it to PBS solution. Then add 40 μL of color developer, incubate for 5 minutes, and use a microplate reader to detect the OD value at 412 nm.

[0084] The experiment set up four groups, namely:

[0085] Sample group A (enzyme solution + substrate solution + buffer + sample solution to be tested / donepezil solution + developer solution), its absorbance value is recorded as A;

[0086] Sample Background Group A 0 (substrate solution + buffer solution + sample solution to be tested / donepezil solution + developer solution), and its absorbance value is recorded as A 0 ;

[0087] The absorbance value of the negative control group B (enzyme solution + substrate solution + buffer + color developing agent solution + DMSO) was recorded as B;

[0088] Negative background control group B 0 (substrate solution + buffer solution + color developing agent solution + DMSO), the absorbance value is recorded as B 0 ;

[0089] The amounts of reagents added in each group are summarized in Table 1.

[0090] After measuring the absorbance value, the corresponding inhibition rate was calculated by the formula, and the curve and the corresponding IC were fitted by Graphpad Prism software. 50 value.

[0091] The inhibition rate formula of the sample on acetylcholinesterase is as follows:

[0092]

[0093] Where:

[0094] A represents the absorbance of the substrate, acetylcholinesterase, in the presence of the sample solvent when the system is incubated at 37°C for 30 min.

[0095] A 0 It indicates the background absorbance of the system incubated at 37°C for 30 min in the presence of sample and solvent when no acetylcholinesterase is added.

[0096] B represents the absorbance of the substrate and acetylcholinesterase system after incubation at 37°C for 30 min.

[0097] B 0 It indicates the absorbance when only substrate and solvent system are added and incubated at 37℃ for 30min.

[0098] Table 1 Sample group A, sample background group A 0 , negative control group B, negative background control group B 0 Summary of reagent addition amounts

[0099]

[0100] Example 1

[0101] (Z)-2-(4-((2-(1H-indole-3-carbonyl)hydrazine)methyl)-2-methoxyphenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is shown below:

[0102]

[0103] The specific synthesis steps are as follows:

[0104] Accurately weigh 1.38 g (10 mmoL) 3-nitroaniline, 0.15 g (2 mmoL) DMF and 4.15 g (30 mmoL) anhydrous K 2 CO 3 Add 100mL round-bottom flask and pour 60mL dichloromethane. Ice bath at 0℃, add 1.68g (15mmoL) chloroacetyl chloride with a 2mL disposable syringe, and the reaction time is 6h. After the reaction is completed, pour the reaction solution into 50mL distilled water, add 3×10mL dichloromethane to extract the aqueous phase three times, combine the organic phases, wash the organic phase with 0.5moL / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated brine in turn, dry the organic phase with anhydrous sodium sulfate, and vacuum evaporation the organic phase solution into a solid, ultrasonicate until the system is uniform and there are no large lumps, to obtain the first intermediate.

[0105] Accurately weigh 2.14 g (10 mmoL) of the first intermediate and 1.52 g (10 mmoL) of vanillin in a 50 mL round-bottom flask, add 15 mL of acetone, dissolve, and then add 0.03 g (0.2 mmoL) of KI and anhydrous K 2 CO 3 2.07g (15mmoL), placed at 55°C for 5 hours. After the reaction is completed, the temperature of the reaction system is lowered to room temperature for filtering, the filter cake is retained and washed with saturated brine to obtain a crude product, the sample is loaded on a column, separated by column chromatography and dissolved in the eluent, and vacuum rotary evaporation is performed to form a solid, ultrasonication is performed until the system is uniform and there are no large lumps, and the second intermediate of the pure compound is obtained after drying.

[0106] Accurately weigh 3.30g (10mmoL) of the second intermediate and 1.75g ​​(10mmoL) of indole-3-carboxylic acid hydrazide in a 50mL round-bottom flask, add 15mL of anhydrous ethanol, and then use a 1mL disposable syringe to draw 0.1mL of acetic acid and add it dropwise to the system, and react at 50°C for 4 hours. After the reaction is completed, wait for the reaction system to cool to room temperature, filter with a glass suction funnel, and collect the filter cake. Rinse with a small amount of anhydrous ethanol in the reaction flask and filter again. Wash the collected filter cake with purified water, anhydrous ethanol, and saturated brine in turn, and finally dry the filter cake to obtain the inhibitor shown in the above formula.

[0107] Experimental Results

[0108] Light yellow powder solid, yield 88%, IC 50 The value was 0.18±0.06μM, and the IC of the positive control drug 50 The value is 0.02±0.01μM.

[0109] 1 H NMR (401 MHz, DMSO-d 6 )δ11.75(s,1H),11.34(s,1H),10.67(s,1H),8.68(t,J=2.2Hz,1H),8.22(d,J=7.7Hz,3H),8.04-7.91(m,2H),7.64(t,J=8.2H z,1H),7.49(dd,J=7.5,1.3Hz,1H),7.41(d,J=1.8Hz,1H),7.27-7.11(m,3H),7.04(d,J=8.3Hz,1H),4.83(s,2H),3.89(s,3H). 13 C NMR (101 MHz, DMSO-d 6)δ167.84,149.93,149.25,148.46,140.06,130.78,129.32,126.01,1 22.70,121.21,118.72,114.37,114.15,112.45,109.18,68.57,56.04.

[0110] Example 2

[0111] (Z)-2-(2-methoxy-4-((2-p-tolylhydrazyl)methyl)phenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0112]

[0113] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0114] Light white powder solid, yield 85%, IC 50 The value was 34.98±2.11μM.

[0115] 1 H NMR (401 MHz, DMSO-d 6 )δ11.29(s,1H),10.64(s,1H),8.67(t,J=2.2Hz,1H),7.97(td,J=8.5,2.2Hz,2H),7.86(s,1H),7.79(d,J=8.0Hz,2H),7.64(t,J=8.2Hz,1H ),7.42(d,J=8.0Hz,2H),7.22(d,J=1.9Hz,1H),7.11(dd,J=8.3,1.9Hz,1H),6.99(d,J=8.3Hz,1H),4.81(s,2H),3.85(s,3H),2.38(s,3H). 13 C NMR (101 MHz, DMSO-d 6 )δ167.69,149.72,149.56,148.43,147.40,143.90,140.02,136.61,130.74,130.09,130.09,1 28.12,127.76,127.76,125.96,121.04,118.68,114.28,114.11,109.86,68.42,56.08,21.48.

[0116] Example 3

[0117] (Z)-2-(4-((2-isonicotinylhydrazide)methyl)-2-methoxyphenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0118]

[0119] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0120] Dark yellow powdery solid, yield 85%, IC 50 The value was 57.13±2.03μM.

[0121] 1 H NMR (401 MHz, DMSO-d 6 )δ12.00(s,1H),10.68(s,1H),8.82-8.76(m,2H),8.68(t,J=2.2Hz,1H),8.41(s,1H),7.97(ddd,J=12.5,8.0,2.3Hz,2H),7.85-7.7 9(m,2H),7.64(t,J=8.2Hz,1H),7.43(d,J=2.0Hz,1H),7.24(dd,J=8.3,1.9Hz,1H),7.05(d,J=8.4Hz,1H),4.85(s,2H),3.90(s,3H). 13 C NMR (101 MHz, DMSO-d 6 )δ167.72,161.98,150.82,150.82,149.96,149.90,149.50,148.45,141.08,140.0 4,130.77,128.36,125.99,122.43,122.01,118.72,114.12,109.39,68.40,56.12.

[0122] Example 4

[0123] (Z)-2-(4-((2-(6-chloropyrimidin-4-yl)hydrazine)methyl)-2-methoxyphenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0124]

[0125] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0126] Gray powdery solid, yield 82%, IC 50 The value was 7.45±1.94μM.

[0127] 1 H NMR (401 MHz, DMSO-d 6 )δ11.01 11.75(s,1H),10.69(s,1H),8.68(q,J=2.2Hz,1H),8.43(d,J=1.7Hz,1H),8.10(d,J=1.9Hz,1H),7.97(ddd,J=

[0128] 13.1,6.2,4.0Hz,2H),7.65(td,J=8.2,1.9Hz,1H),7.45(d,J=2.0Hz,1H),7.24 (dd,J=6.2,2.1Hz,2H),7.02(dd,J=8.3,1.9Hz,1H),4.83(s,2H),3.92(s,3H). 13 C NMR (101 MHz, DMSO-d 6 )δ167.77,162.67,159.85,158.85,149.90,149.48,148.43,145.03,140.05,130.7 4,128.59,125.96,121.47,118.69,114.24,114.11,109.76,102.02,68.47,56.23.

[0129] Example 5

[0130] (Z)-2-(2-methoxy-4-((2-(pyrazine-2-carbonyl)hydrazine)methyl)phenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0131]

[0132] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0133] Gray powdery solid, yield 83%, IC 50 The value is 0.20±0.04μM.

[0134] 1 H NMR (401 MHz, DMSO-d 6)δ12.21(s,1H),10.68(s,1H),9.27(d,J=1.5Hz,1H),8.93(d,J=2.5Hz,1H),8.79(dd,J=2.5,1.5Hz,1H),8.68(t,J=2.2Hz,1H),8.59(s,1H), 8.13–7.84(m,2H),7.64(t,J=8.2Hz,1H),7.42(d,J=1.9Hz,1H),7.21(dd,J=8.4,1.9Hz,1H),7.06(d,J=8.3Hz,1H),4.85(s,2H),3.90(s,3H). 13 C NMR (101 MHz, DMSO-d 6 )δ(101MHz,DMSO-d6)δ167.57,159.61,159.21,157.06,144.55,130.10,128.05,126.32,124.52,114 .95,107.34,105.74,102.75,101.18,96.95,67.99,66.47,56.53,55.09,16.09,15.06,14.83,13.76.

[0135] Example 6

[0136] (Z)-2-(2-methoxy-4-((2-pentanoylhydrazine)methyl)phenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0137]

[0138] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0139] White powdery solid, yield 80%, IC 50 The value was 30.96±2.18μM.

[0140] 1 H NMR (401 MHz, DMSO-d 6)δ11.19(d,J=42.1Hz,1H),10.65(s,1H),8.67(t,J=2.2Hz,1H),8.01-7.93(m,2H),7.90 (s,1H),7.64(t,J=8.2Hz,1H),7.33(dd,J=13.7,1.9Hz,1H),7.15(dd,J=8.3,1.9Hz,1H) ,7.01(dd,J=8.4,2.6Hz,1H),4.80(s,2H),3.85(s,3H),2.61(t,J=7.4Hz,1H),2.19(t,J =7.4Hz, 1H), 1.57 (h, J = 7.6Hz, 2H), 1.34 (tt, J = 15.3, 7.5Hz, 2H), 0.90 (q, J = 7.1Hz, 3H). 13 C NMR (101 MHz, DMSO-d 6 )δ169.00,167.78,149.84,149.49,149.21,148.45,140.04,130.77,128.89,125.99 ,121.82,120.83,118.71,114.43,109.25,68.51,56.07,34.43,27.71,22.46,14.22.

[0141] Example 7

[0142] (Z)-2-(4-((2-(4-(dimethylamino)benzoyl)hydrazine)methyl)-2-methoxyphenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0143]

[0144] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0145] Yellow-white powder solid, yield 81%, IC 50 The value was 8.94±1.03μM.

[0146] 1 H NMR (401 MHz, DMSO-d 6)δ11.48(s,1H),10.68(s,1H),8.69(t,J=2.2Hz,1H),8.39(s,1H),7.99(ddd,J=14.6,7.9,2.2Hz,2H),7.83(d,J=8.6Hz,2H),7.65(t,J=8. 2Hz,1H),7.46-7.33(m,1H),7.18(dd,J=8.3,1.9Hz,1H),7.04(d,J=8.3Hz,1H),6.88-6.64(m,2H),4.83(s,2H),3.89(s,3H),3.01(s,6H). 13 C NMR (101 MHz, DMSO-d 6 )δ167.80,152.92,149.89,149.41,148.44,140.06,130.75,130.75,129.57,129.15,125.99, 121.79,120.05,120.05,118.69,114.24,114.13,111.31,109.14,68.51,56.05,40.21,40.18.

[0147] Example 8

[0148] (Z)-2-(4-((2-(cyclopropanecarbonyl)hydrazine)methyl)-2-methoxyphenoxy)-N-(3-nitrophenyl)acetamide, the structural formula of which is as follows:

[0149]

[0150] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0151] Yellow-white powder solid, yield 79%, IC 50 The value was 19.33±1.34μM.

[0152] 1 H NMR (401 MHz, DMSO-d 6)δ11.41(d,J=97.4Hz,1H),10.65(s,1H),8.67(t,J=2.2Hz,1H),8.04-7.90(m,2H),7.64(t,J=8.2Hz,1H),7.35(dd,J=5.3,1.9Hz, 1H),7.17(dt,J=8.5,2.5Hz,1H),7.01(dd,J=8.4,3.3Hz,1H),4.81(s,2H),3.87(s,3H),2.68(p,J=6.3Hz,1H),0.97-0.70(m,4H). 13 C NMR (101 MHz, DMSO-d 6 )δ174.93,169.67,149.86,149.47,149.26,148.44,143.21,140.04,130.76,12 5.99,121.79,118.70,114.13,109.60,109.32,68.53,56.11,13.35,8.40,8.40.

[0153] Example 9

[0154] (Z)-N-(2,6-dimethylphenyl)-2-(2-methoxy-4-((2-p-tolylhydrazinoethylidene)methyl)phenoxy)acetamide, the structural formula of which is as follows:

[0155]

[0156] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0157] Dark yellow powdery solid, yield 90%, IC 50 The value was 30.77±2.08μM.

[0158] 1 H NMR (401 MHz, DMSO-d 6 )δ11.28(s,1H),9.41(s,1H),7.85(s,1H),7.77(d,J=8.0Hz,2H),7.40(d,J=8.2Hz,2H),7.19(d,J=1.9Hz,1H),

[0159] 7.14-6.96(m,5H),4.77(s,2H),3.81(s,3H),2.36(s,3H),2.11(s,6H). 13 C NMR (101 MHz, DMSO-d6 )δ166.75,149.72,147.47,143.92,143.92,136.63,135.76,134.81,130.11,130.11,128.20,128 .20,128.06,127.79,127.79,127.15,120.99,114.18,109.82,68.29,56.10,21.51,18.58,18.57.

[0160] Example 10

[0161] (Z)-N-(2,6-dimethylphenyl)-2-(4-((2-isonicotinylhydrazide)methyl)-2-methoxyphenoxy)acetamide, the structural formula of which is as follows:

[0162]

[0163] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0164] White powdery solid, yield 84%, IC 50 The value was 95.24±1.84μM.

[0165] 1 H NMR (401 MHz, DMSO-d 6 )δ12.01(s,1H),9.46(s,1H),8.88-8.72(m,2H),8.43(s,1H),7.92-7.77(m,2H),7.43(d,J=1.9 Hz,1H),7.29(dd,J=8.4,1.9Hz,1H),7.16-7.03(m,4H),4.84(s,2H),3.90(s,3H),2.15(s,6H). 13 C NMR (101 MHz, DMSO-d 6 )δ166.78,162.01,150.83,150.83,150.10,149.97,149.50,135.79,135.79,134.83,128.30, 128.22,128.22,127.16,122.21,122.04,122.04,114.05,109.52,68.26,56.14,18.60,18.60.

[0166] Embodiment 11

[0167] (Z)-2-(4-((2-(1H-indole-3-carbonyl)hydrazine)methyl)-2-methoxyphenoxy)-N-(2,6-dimethylphenyl)acetamide, the structural formula of which is as follows:

[0168]

[0169] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0170] White powdery solid, yield 83%, IC 50 The value was 8.55±1.21μM.

[0171] 1 H NMR (401 MHz, DMSO-d 6 )δ11.77(s,1H),11.36(s,1H),9.46(s,1H),8.23(d,J=7.7Hz,2H),7.50(d,J=7.9Hz,1H),7.42(d,J=2.0Hz,1H),

[0172] 7.27-7.13(m,3H),7.13-7.03(m,4H),4.83(s,2H),3.90(s,3H),2.16(s,6H). 13 CNMR (101MHz, DMSO-d 6 )δ166.89,150.00,149.40,135.80,135.80,134.86,129.25,128.23,128. 22,127.16,122.71,121.23,114.30,112.47,109.27,56.06,18.60,18.60.

[0173] Example 12

[0174] (Z)-2-(4-((2-(6-chloropyrimidin-4-yl)hydrazine)methyl)-2-methoxyphenoxy)-N-(2,6-dimethylphenyl)acetamide, the structural formula of which is as follows:

[0175]

[0176] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0177] Gray powdery solid, yield 79%, IC 50The value was 27.42±1.23μM.

[0178] 1 H NMR (401 MHz, DMSO-d 6 )δ11.75(s,1H),9.44(s,1H),8.42(s,1H),8.10(s,1H),7.43(d,J=1.9Hz,1H) ,7.31-7.20(m,2H),7.13-6.99(m,4H),4.80(s,2H),3.89(s,3H),2.13(s,6H). 13 C NMR (101 MHz, DMSO-d 6 )δ166.82,162.68,159.87,158.89,149.99,149.66,145.13,135.78,134.83,128.52, 128.21,128.21,127.15,121.38,114.23,109.84,102.03,68.37,56.28,18.59,18.59.

[0179] Example 13

[0180] (Z)-N-(2,6-dimethylphenyl)-2-(2-methoxy-4-((2-(pyrazine-2-carbonyl)hydrazine)methyl)phenoxy)acetamide, the structural formula of which is as follows:

[0181]

[0182] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0183] Yellow powdery solid, yield 82%, IC 50 The value was 7.91±0.87μM.

[0184] 1 H NMR (401 MHz, DMSO-d 6 )δ12.22(s,1H),9.46(s,1H),9.27(d,J=1.5Hz,1H),8.93(d,J=2.5Hz,1H),8.79(dd,J=2.5,1.5Hz,1H),8.58(s,1 H),7.41(d,J=1.9Hz,1H),7.24(dd,J=8.3,1.9Hz,1H),7.13-7.02(m,4H),4.83(s,2H),3.89(s,3H),2.14(s,6H). 13C NMR (101 MHz, DMSO-d 6 )δ166.77,159.87,150.28,150.09,149.97,148.28,145.26,144.59,143.82,135.79,134.83, 134.83,128.42,128.22,128.22,127.16,122.24,114.06,109.51,68.28,56.15,18.60,18.60.

[0185] Embodiment 14

[0186] (Z)-N-(2,6-dimethylphenyl)-2-(2-methoxy-4-((2-pentanoylhydrazine)methyl)phenoxy)acetamide, the structural formula of which is as follows:

[0187]

[0188] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0189] White powdery solid, yield 78%, IC 50 The value was 57.93±2.03μM.

[0190] 1 H NMR (401 MHz, DMSO-d 6 )δ11.19(d,J=44.5Hz,1H),9.43(s,1H),8.01(d,J=73.1Hz,1H),7.32(dd,J=11 .6,1.9Hz,1H),7.17(ddd,J=8.6,4.7,1.9Hz,1H),7.12-6.99(m,4H),4.79(s,2 H),3.85(s,3H),2.62(t,J=7.4Hz,1H),2.19(t,J=7.4Hz,1H),2.13(s,6H),1.5 7(dp,J=12.9,7.6Hz,2H), 1.33(dq,J=17.1,7.4Hz,2H), 0.90(q,J=7.3Hz,3H). 13 C NMR (101 MHz, DMSO-d 6 )δ

[0191] 169.01,166.83,149.91,149.39,146.18,135.78,135.78,134.83,128.83,128.21,128.21,127.15,120.77,114.38,114.10,68.33,56.10,34.43,27.74,22.47,18.58,18.58,14.28.

[0192] Embodiment 15

[0193] (Z)-2-(4-((2-(4-(dimethylamino)benzoyl)hydrazine)methyl)-2-methoxyphenoxy)-N-(2,6-dimethylphenyl)acetamide, the structural formula of which is as follows:

[0194]

[0195] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0196] White powdery solid, yield 76%, IC 50 The value was 39.86±2.64μM.

[0197] 1 H NMR (401 MHz, DMSO-d 6 )δ11.49(s,1H),9.45(s,1H),8.40(s,1H),7.84(d,J=8.9Hz,2H),7.39(d,J=1.9Hz,1H),7.22(dd,J=8.4,1.9 Hz,1H),7.10(dd,J=3.3,2.0Hz,4H),6.86-6.70(m,2H),4.82(s,2H),3.89(s,3H),3.01(s,6H),2.15(s,6H). 13 C NMR (101 MHz, DMSO-d 6 )δ166.85,149.96,149.54,135.79,135.79,134.85,129.57,129.57,129.10,128.22,128.22 ,127.16,121.53,114.20,111.33,111.33,109.32,68.38,56.10,40.22,40.01,18.60,18.60.

[0198] Example 16

[0199] (Z)-2-(4-((2-(cyclopropanecarbonyl)hydrazine)methyl)-2-methoxyphenoxy)-N-(2,6-dimethylphenyl)acetamide, the structural formula of which is as follows:

[0200]

[0201] The preparation was similar to that of Example 1, except that: 1 , R 2 , using the corresponding substituted aniline and substituted hydrazine.

[0202] White powdery solid, yield 77%, IC 50 The value was 37.17±2.17μM.

[0203] 1 H NMR (401 MHz, DMSO-d 6 )δ11.44(d,J=93.7Hz,1H),9.45(s,1H),8.07(d,J=54.5Hz,1H),7.36(dd,J=6.6,1.9Hz,1H),7.22(dd,J=8.3,1. 9Hz,1H),7.09(d,J=4.2Hz,4H),4.82(s,2H),3.87(s,3H),2.71(p,J=6.4Hz,1H),2.15(s,6H),0.95-0.73(m,4H). 13 CNMR (101MHz, DMSO-d 6 )δ174.93,166.84,149.94,145.81,135.78,135.78,134.84,128.75,128.21,128.2 1,127.15,120.95,109.66,109.45,68.39,56.13,18.59,13.35,10.22,8.42,7.38.

[0204] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A Schiff base vanillin acetylcholinesterase inhibitor, characterized in that: Having a structure as shown in formula (I): In formula (I), R1 is a phenyl group to which a substituted group is attached, and R2 is a group containing a carbonyl group, a sulfone group or a heterocyclic ring.

2. The Schiff base vanillin acetylcholinesterase inhibitor according to claim 1, characterized in that: The R1 is selected from: One of them.

3. The Schiff base vanillin acetylcholinesterase inhibitor according to claim 1, characterized in that: The R2 is selected from: One of them.

4. The Schiff base vanillin acetylcholinesterase inhibitor according to claim 1, characterized in that: The Schiff base vanillin acetylcholinesterase inhibitor is:

5. The Schiff base vanillin acetylcholinesterase inhibitor according to claim 1, characterized in that: The Schiff base vanillin acetylcholinesterase inhibitor is:

6. A method for preparing the Schiff base vanillin acetylcholinesterase inhibitor according to any one of claims 1 to 5, characterized in that: The steps include: S1: mixing substituted aniline and chloroacetyl chloride and reacting them with nucleophilic substitution to obtain a first intermediate; S2: mixing the first intermediate with vanillin and causing a first reaction to obtain a second intermediate; S3: The second intermediate is mixed with a substituted hydrazine and subjected to a second reaction to obtain the Schiff base vanillin acetylcholinesterase inhibitor.

7. The method for preparing a Schiff base vanillin acetylcholinesterase inhibitor according to claim 6, characterized in that: In step S1, the nucleophilic substitution reaction is carried out in dichloromethane, using DMF as a catalyst and anhydrous K2CO3 as an acid-binding agent; the molar ratio of substituted aniline to chloroacetyl chloride is 10-20:15-20; the reaction temperature is 0-5°C, and the reaction time is 6-8h.

8. The method for preparing a Schiff base vanillin acetylcholinesterase inhibitor according to claim 6, characterized in that: In step S2, the first reaction is carried out in acetone, using KI as a catalyst and anhydrous K2CO3 as an acid-binding agent; the molar ratio of the first intermediate to vanillin is 10-20:10-20; the reaction temperature is 50-70°C, and the reaction time is 4-6h.

9. The method for preparing a Schiff base vanillin acetylcholinesterase inhibitor according to claim 6, characterized in that: In step S3, the second reaction is carried out in anhydrous ethanol, using acetic acid as a catalyst; the molar ratio of the second intermediate to the substituted hydrazine is 10-20:10-20; the reaction temperature is 50-65° C., and the reaction time is 4-6 hours.

10. Use of the Schiff base vanillin acetylcholinesterase inhibitor according to any one of claims 1 to 5 in the preparation of a drug for inhibiting acetylcholinesterase activity.

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