N-disubstituted benzamide compound as well as preparation method and application thereof

Abstract

The invention discloses an N-disubstituted benzamide compound as well as a preparation method and application thereof, and belongs to the technical field of medicines. The N-disubstituted benzamide compound disclosed by the invention has a structure as shown in a general formula (I) or (II) or a pharmaceutically acceptable salt of the N-disubstituted benzamide compound. The compound prepared by the invention has relatively strong tubulin polymerization inhibition activity and remarkable in-vivo and in-vitro anti-tumor activity. Therefore, the compound provided by the invention can be used for preparing medicines for treating malignant tumors and diseases related to differentiation and proliferation. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the field of pharmaceutical technology, and specifically, to an N-disubstituted benzamide compound, a preparation method thereof, and an application thereof. Background Art

[0002] Malignant tumors are common diseases that endanger human life and health. They are the second leading cause of death globally after cardiovascular and cerebrovascular diseases and are also one of the most serious crises faced by the world's public health systems. Discovering and developing new anti-tumor drugs has always been a major clinical need.

[0003] Microtubules are polymerized from heterodimers of α and β tubulins. These heterodimers are joined end to end to assemble into linear protofilaments. Subsequently, the protofilaments are further polymerized in a polar manner to form microtubules. Microtubules have positive and negative ends. The positive end exposes β-tubulin, and the negative end has the α subunit. The process of GTP binding and hydrolysis at the microtubule ends is directly related to the dynamic changes of microtubules. The dynamic equilibrium of microtubules plays an important role in various cellular functions such as cell signaling, cell morphology, intracellular transport, and mitosis. Any factor that affects the dynamic equilibrium of microtubule assembly will cause cells to undergo G2 / M cycle arrest, thereby affecting cell growth and proliferation and even causing cell death. Tubulin is an important target for cancer treatment. In recent years, with the continuous development and progress of structural biology, a series of microtubule targets have been discovered one after another, and different mechanisms of action have been elucidated at the molecular level.

[0004] Targeting tubulin is one of the most important strategies in drug research and development and is also one of the most successful cases in the history of anti-tumor drug research and development. Although more precise targeted drug research and development strategies have achieved great success since the new century, traditional chemotherapy drugs still have irreplaceable advantages in clinical anti-tumor treatment. For example, taxanes are still currently first-line anti-tumor drugs. In recent years, the research and development of new tubulin inhibitors has still been highly active, and candidate drugs continue to enter clinical research. Despite the great success of microtubule-targeted drugs in clinical practice, the clinical application of traditional microtubule-targeted drugs (such as paclitaxel and vinblastine) is limited by drug resistance and toxicity, and more new microtubule-targeted drugs are urgently needed to be discovered.

[0005] Combretastatin A4 (CA-4) is a cis - stilbene compound isolated from the bark of Combretum caffum. It can bind to the colchicine - binding site of tubulin, blocking microtubule assembly, thereby rapidly occluding tumor blood vessels and causing tumor cell death. However, CA - 4 has problems of poor solubility and poor chemical stability. Under conditions of light, heat, or acidic medium, and after in - vivo administration, cis - stilbene is easily isomerized to trans - stilbene, and the activity of trans - stilbene in inhibiting tubulin polymerization and cancer cell growth is significantly reduced. To maintain the cis - configuration of the two aromatic rings, researchers considered introducing various linking groups to replace the double bond, such as heterocycles including imidazole, 2(5 H ), - furanone, oxazolone, 4 - arylcoumarin, furazan, triazole, dihydroisoxazole, 2 - aminothiazole, tetrazole, and indole, as well as carbocycles including cyclopropane and cyclopentenone. In addition, the cis - stilbene configuration can also be maintained by introducing various bridging functional groups, such as ketone, thioether, ether, nitrile, and sulfonate. However, the compounds involved in the present invention are different from all the above - reported CA - 4 derivatives. Summary of the Invention

[0006] The first object of the present invention is to provide an N - disubstituted benzamide compound and its pharmaceutically acceptable salts.

[0007] The second object of the present invention is to provide a method for preparing the N - disubstituted benzamide compound as described above.

[0008] The third object of the present invention is to provide the use of the N - disubstituted benzamide compound as described above in the preparation of anti - tumor drugs.

[0009] To achieve the above - mentioned first object, the present invention discloses an N - disubstituted benzamide compound, which is characterized by having the structure shown in the following general formula (Ⅰ) or (Ⅱ), as well as its optical isomers, diastereoisomers, and racemic mixtures, and its pharmaceutically acceptable salts;

[0010] Wherein: R represents phenyl, heterocycle, acyl, alkyl or heteroalkyl with 1 to 8 carbon atoms, a group in which alkyl or heteroalkyl with 1 to 8 carbon atoms is connected to phenyl, a group in which alkyl or heteroalkyl with 1 to 8 carbon atoms is connected to a heterocycle, a saturated or unsaturated straight - chain alkyl or heteroalkyl with 1 to 8 carbon atoms, a group in which alkyl or heteroalkyl with 1 to 8 carbon atoms is connected to an amide bond, a group in which phenyl is connected to an alkane chain containing an amide bond, phenyl.

[0011] The terms and definitions used in the present invention have the following meanings: "Substituent" is selected from any one or more of the following: hydrogen atom, halogen atom, straight-chain alkyl group with 1 to 6 carbon atoms, branched-chain alkyl group with 3 to 6 carbon atoms, hydroxyl group, mercapto group, carboxyl group, alkenyl group, cyano group, cyanomethyl group, amino group, aminoalkyl group (such as aminomethyl, etc.), nitro group, trifluoromethyl group, trifluoromethoxy group, methoxy group, methylthio group, ethoxy group, propoxy group, isopropoxy group, butoxy group, acetyl group, etc.

[0012] "Aryl group" refers to an aromatic carbocyclic group. Preferably, the aromatic ring contains 5 to 10 carbon atoms.

[0013] "Heteroaryl group" refers to an aromatic heterocycle, which can be a monocyclic, bicyclic or fused-ring group. Preferably, the heteroaryl group includes thienyl group, furyl group, pyrrolyl group, pyridyl group, pyrazinyl group, thiazolyl group, pyrimidinyl group, quinolinyl group, benzothiazolyl group, benzofuryl group or indolyl group, etc.

[0014] "Aroyl group" refers to a group in which an aromatic carbocyclic ring is connected to a carbonyl group at the end. Preferably, the aromatic ring contains 5 to 10 carbon atoms.

[0015] "Heteroalkyl" is a saturated or unsaturated chain containing carbon atoms and at least one heteroatom, and any two heteroatoms are not adjacent. The heteroalkyl can be straight-chain or branched-chain, substituted or unsubstituted.

[0016] "Pharmaceutically acceptable salt" refers to a salt form of the compound of formula (I) or (II) that has therapeutic efficacy and is non-toxic. Many such salts are known in the art. Cationic salts formed on any acidic group (such as carboxyl group), or anionic salts formed on any basic group (such as amino group), and many of these salts are known in the art. For example, cationic salts include salts of alkali metals (such as sodium and potassium) and alkaline earth metals (magnesium and calcium) and organic salts (such as ammonium salts). Anionic salts can also be conveniently obtained by treating the basic form of (I) or (II) with the corresponding acid. Such acids include inorganic acids such as sulfuric acid, nitric acid, phosphoric acid, hydrochloric acid, etc.; or organic acids such as acetic acid, propionic acid, glycolic acid, 2-hydroxypropionic acid, 2-oxopropionic acid, oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, malic acid, tartaric acid, 2-hydroxy-1,2,3-propanetricarboxylic acid, ethanesulfonic acid, benzenesulfonic acid, cyclohexylsulfinic acid, 2-hydroxybenzoic acid, 4-amino-2-hydroxybenzoic acid, etc. In addition, those skilled in the art can choose a certain salt and discard another salt according to factors such as solubility, stability, ease of formulation, etc. The determination and optimization of these salts are within the experience of those skilled in the art.

[0017] Among the above N-disubstituted benzamide compounds and their pharmaceutically acceptable salts, the pharmaceutically acceptable salts do not contain crystal water, or contain one or more crystal waters.

[0018] The definitions of "optical isomers", "enantiomers", "diastereoisomers", "racemates", etc. used in the present invention define all possible stereoisomeric forms of the compounds or physiological derivatives of the present invention. Unless otherwise specified, the chemical naming of the compounds of the present invention includes mixtures of all possible stereochemical forms, and such mixtures include all diastereoisomers and enantiomers of the basic structural molecules, as well as individual isomeric forms of the substantially pure compounds of the present invention, that is, those containing less than 10%, preferably less than 5%, particularly less than 2%, and most preferably less than 1% of other isomers.

[0019] The compounds of formula (I) or (II) may also exist in other protected forms or derivative forms, which are obvious to those skilled in the art and should all be included within the scope of the present invention.

[0020] Furthermore, as a preferred embodiment of the present invention, the N-disubstituted benzamide compounds of formula (I) or (II) are preferably: Compound 5a: N -ethyl- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5b: N -(3-hydroxy-4-methoxyphenyl)- N -isopropyl-3,4,5-trimethoxybenzamide; Compound 5c: N -(cyclopropylmethyl)- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5d: N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(thiophen-2-ylmethyl)benzamide; Compound 5e: N -((3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(thiazol-5-ylmethyl)benzamide; Compound 5f: N -((1 H -pyrrol-2-yl)methyl)- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5g: N -cyclobutyl- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5h: N-(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(oxetan-3-yl)benzamide; Compound 5i: N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(2,2,2-trifluoroethyl)benzamide; Compound 9a: N -ethyl-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9b: 3-hydroxy- N -isopropyl-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9c: N -(cyclopropylmethyl)-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9d: 3-hydroxy-4-methoxy- N -(thiophen-2-ylmethyl)- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9e: 3-hydroxy-4-methoxy- N -(thiazol-5-ylmethyl)- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9f: N -((1 H -pyrrol-2-yl)methyl)-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9g: N -cyclobutyl-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9h: 3-hydroxy-4-methoxy- N -(oxetan-3-yl)- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9i: 3-hydroxy-4-methoxy- N -(2,2,2-trifluoroethyl)- N -(3,4,5-trimethoxyphenyl)benzamide.

[0021] Their structural formulas and NMR and mass spectrometry data are shown in Table 1 below:

[0022]

[0023]

[0024]

[0025]

[0026] To achieve the second object of the present invention, the present invention discloses a preparation method of N-disubstituted benzamide compounds 5a-i and 9a-i: General method 1 of the reaction process: Synthesis method of compounds 5a-h:

[0027] The reagents and conditions in the above reaction formula: (a) TBDPSCl, DMAP, imidazole, dichloromethane, 0 °C, 2 hours, yield 55%; (b) sodium triacetoxyborohydride, dichloroethane, room temperature, 4 hours, yield 45-80%; (c) HATU, DIPEA, N, N-dimethylformamide, room temperature, 2 hours, yield 69-77%; (d) TBAF, tetrahydrofuran, 0 °C, 18 hours, yield 80-92%.

[0028] Using commercially available 3-hydroxy-4-methoxyaniline 1 as the starting material, first react with tert-butyldiphenylchlorosilane (TBDPSCl) to obtain the key intermediate 2, and then react with aldehyde or ketone through reductive amination reaction to generate compounds 3a-h; then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as the condensing agent, compounds 3a-h react with 3,4,5-trimethoxybenzoic acid to generate the corresponding amides 4a-h respectively; finally, compounds 4a-h are deprotected under the action of tetrabutylammonium fluoride (TBAF) to obtain the target products 5a-h.

[0029] General method 2 of the reaction process: Synthesis of compounds 9a-h:

[0030] The reagents and conditions in the above reaction formula: (a) sodium triacetoxyborohydride, dichloroethane, room temperature, 4 hours, yield 55-88% (b) HATU, DIPEA, N, N-dimethylformamide, room temperature, 2 hours, yield 75-86%; (c) sodium hydroxide, methanol, room temperature, 2 hours, yield 93-96%.

[0031] Using commercially available 3,4,5-trimethoxyaniline 6 as the starting material, it reacts with aldehyde or ketone through reductive amination reaction to generate compounds 7a-h; then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as the condensing agent, compounds 7a-h react with 3-acetoxy-4-methoxybenzoic acid respectively to generate the corresponding amides 8a-h; finally, compounds 8a-h are treated with sodium hydroxide to obtain the target products 9a-h.

[0032] General method for reaction process three: Synthesis of compound 5i

[0033] The reagents and conditions in the above reaction formula: (a) TFAH, DMAP, dichloromethane, room temperature, 2 hours, yield 95%; (b) BH3, THF, room temperature, 4 hours, yield 72%; (c) HATU, DIPEA, N, N-dimethylformamide, room temperature, 2 hours, yield 73%; (d) TBAF, tetrahydrofuran, 0 °C, 18 hours, yield 81%.

[0034] Intermediate 2 reacts with trifluoroacetic anhydride to obtain compound 6i, and then is reduced by borane to obtain the corresponding secondary amine 3i; then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as the condensing agent, compound 3i reacts with 3,4,5-trimethoxybenzoic acid to generate the corresponding amide 4i; finally, compound 4i is deprotected under the action of tetrabutylammonium fluoride (TBAF) to obtain the target product 5i.

[0035] General method for reaction process four: Synthesis of compound 9i:

[0036] The reagents and conditions in the above reaction formula: (a) TFAH, DMAP, dichloromethane, room temperature, 2 hours, yield 97%; (b) BH3, THF, room temperature, 4 hours, yield 75%; (c) HATU, DIPEA, N, N-dimethylformamide, room temperature, 2 hours, yield 80%; (d) sodium hydroxide, methanol, room temperature, 2 hours, yield 95%.

[0037] Starting material 3,4,5-trimethoxyaniline 6 reacts with trifluoroacetic anhydride to obtain compound 10i, and then is reduced by borane to obtain the corresponding secondary amine 7i; then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as the condensing agent, compound 7i reacts with 3-acetoxy-4-methoxybenzoic acid to generate the corresponding amide 8i; finally, compound 8i is treated with sodium hydroxide to obtain the target product 9i.

[0038] To achieve the third object of the present invention, the present invention provides the use of the N-disubstituted benzamide compounds or pharmaceutically acceptable salts thereof in the preparation of tubulin polymerization inhibitors and in the preparation of anti-tumor drugs. The tumors include breast cancer and the like. The experimental results show that all the tested typical compounds have significant anti-tumor cell proliferation activities, and their IC50 values are between 2.17 - 90.60 nM. Among them, for human breast cancer cells (MDA-MB-453), the anti-tumor cell proliferation activities of compounds 5c and 5i are stronger than those of the positive drug CA-4, and the activity of compound 5b is comparable to that of CA-4. In addition, all the tested typical compounds have significant tubulin polymerization inhibitory effects at a drug concentration of 10 μM, and their inhibition rate values are between 60% - 79%. Among them, the inhibitory activity of compound 5c on tubulin is comparable to that of the positive drug CA-4. Further, compound 5c exhibits excellent in vivo inhibitory activity, and the in vivo tumor inhibition rate is 69.6%, which is better than that of the positive drug CA-4 control group (61.8%) at the same dose.

[0039] The compositions of some compounds disclosed by the present invention are prepared into various pharmaceutical compositions with one or more pharmaceutically acceptable carriers, excipients or diluents, including injections (lyophilized powder injections, aqueous injections, infusion solutions), various solid oral preparations, liquid oral preparations, etc.

[0040] When administered parenterally, the anti-tumor active compounds of the present invention can be formulated into injection forms for administration, and the dosage depends on the treatment object, administration method, symptoms and other factors. The compounds of the present invention are effective in a quite wide dosage range. For example, the daily dosage can be in the range of about 0.1 mg - 1000 mg per kilogram of body weight. In the treatment of adults, the dosage range is preferably 1 mg / kg - 10 mg / kg, administered once or several times. The actual dosage of the compounds of the present invention to be injected should be determined by a doctor according to relevant circumstances, including the physical condition, age, weight of the treated person, individual response of the patient to the drug, severity of the patient's symptoms, etc. Therefore, the above dosage range does not limit the scope of the present invention in any way. Materials such as mannitol and sodium chloride can be used as carriers to prepare the freeze-dried powder injections for injection to ensure the form and dissolution performance of the powder injections.

[0041] When administered orally, the composition can be formulated into tablets, dispersible tablets, dragees, granules, dry powders, solutions or capsules. Lactose or starch can be used as a carrier for preparing the oral pharmaceutical composition, and gelatin, sodium carboxymethyl cellulose, methyl cellulose, polyvinylpyrrolidone, etc. are suitable binders. Starch or microcrystalline cellulose can be selected as a disintegrant, and talc, colloidal silica, glyceryl stearate, calcium or magnesium stearate, polyethylene glycol-4000, polyethylene glycol-6000, sodium metabisulfite, etc. are often used; as suitable anti-adhesives and lubricants. For example, tablets can be prepared by pressing wet granules. The active ingredient is combined with a carrier and optionally with a portion of a disintegrating additive to form a mixture, which is granulated with an aqueous solution of a binder, an alcoholic or aqueous-alcoholic solution in a suitable apparatus, and the dried granules are then added with other disintegrants, lubricants and anti-adhesives to press the mixture into tablets.

[0042] The advantages of the present invention are as follows: 1. Through the experiments on the inhibitory activity of tubulin polymerization and the anti-tumor cell proliferation activity in vitro of the compounds, it is found that the preferred compounds of the present invention not only have a strong inhibitory activity on tubulin polymerization, but also have a significant anti-breast cancer cell proliferation activity in vitro. The preferred compounds have excellent in vivo tumor growth inhibitory activity, indicating their potential use in cancer treatment.

[0043] 2. Compared with the prior art, the present invention opens up a new way for the in-depth research and development of anti-tumor drugs of new structural types and provides new molecular entities. Detailed implementation mode

[0044] The present invention will be described below through specific implementation examples. Unless otherwise specified, the technical means used in the present invention are all methods well known to those skilled in the art. In addition, the implementation examples should be understood as illustrative rather than limiting the scope of the present invention. The essence and scope of the present invention are only defined by the claims. For those skilled in the art, various changes or modifications to the material components and dosages in these implementation examples also belong to the protection scope of the present invention without departing from the essence and scope of the present invention. The raw materials and reagents used in the present invention are all commercially available (please check carefully). Examples

[0045] Preparation N -Ethyl- N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide (5a) (I) Preparation of Intermediate 2: 3-((tert-Butyldiphenylsilyl)oxy)-4-methoxyaniline To a solution of 3-hydroxy-4-methoxyaniline (0.10 g, 0.72 mmol) dissolved in 10 mL of dichloromethane were added imidazole (0.058 g, 0.86 mmol) and 4-dimethylaminopyridine (ca. 0.01 mmol). The mixture was cooled to 0 °C, tert-butyldiphenylchlorosilane (0.23 mL, 0.86 mmol) was added, and the resulting solution was stirred at room temperature for 2 h. After completion of the reaction, the reaction solution was purified by flash column chromatography (hexane to ethyl acetate volume ratio of 2:1) to give compound 2, 0.15 g, yield 55%. 1 H NMR (600 MHz, DMSO- d 6) δ 7.62 – 7.56 (m, 1H), 7.39 –7.32 (m, 5H), 6.47 (d, J = 8.4 Hz, 1H), 6.20 (d, J = 2.2 Hz, 1H), 5.94 (dd, J = 8.4, 2.2 Hz, 1H), 5.60 (d, J = 5.3 Hz, 1H), 5.00 (d, J = 5.3 Hz, 1H), 3.80(s, 2H), 1.10 (s, 5H). 13 C NMR (150 MHz, DMSO- d 6) δ 146.87, 144.99, 144.62,134.49, 134.13, 129.98, 127.18, 114.84, 105.74, 104.57, 56.22, 26.53, 22.32. (II) Preparation of intermediate 3a: 3-((tert-butyldiphenylsilyl)oxy)- N -ethyl-4-methoxyaniline In a single-necked flask, intermediate 2 (3.77 g, 10 mmol), acetaldehyde (0.66 g, 15 mmol) and 35 mL of 1,2-dichloroethane were added. After stirring and dissolving, sodium triacetoxyborohydride (6.36 g, 30 mmol) was added, and the reaction was carried out at room temperature for 4 h. After completion of the reaction, the reaction solution was separated by column chromatography to give compound 3a, 3.24 g, yield 80%. 1 H NMR (600 MHz, DMSO- d 6) δ 7.65 – 7.56 (m, 3H), 7.36 (ddt, J= 5.0, 3.5, 2.0 Hz, 4H), 6.52 (d, J =8.7 Hz, 1H), 6.31 (dd, J = 8.6, 2.0 Hz, 1H), 6.07 (d, J = 2.1 Hz, 1H), 3.80(s, 1H), 3.26 – 3.20 (m, 1H), 1.29 (t, J = 6.1 Hz, 2H), 1.10 (s, 4H). 13 C NMR(150 MHz, DMSO- d 6) δ 148.72, 147.21, 145.69, 134.49, 134.13, 129.98, 127.18,115.88, 111.12, 105.00, 56.22, 37.75, 26.53, 22.32, 14.32. (III) Preparation of Intermediate 4a: N -(3-((tert-Butyldiphenylsilyl)oxy)-4-methoxyphenyl)- N -ethyl-3,4,5-trimethoxyaniline Intermediate 3a (4.05 g, 10 mmol) was dissolved in 50 mL of DMF, and 3,4,5-trimethoxybenzoic acid (commercially available) (2.12 g, 10 mmol), HATU (3.80 g, 10 mmol), and DIPEA (2.40 g, 20 mmol) were added. The reaction was carried out at room temperature for 4 hours. After the reaction, the reaction solution was poured into 200 mL of water, extracted with ethyl acetate, the organic phases were combined, dried over anhydrous sodium sulfate, and the solvent was evaporated. Intermediate 4a was obtained by column chromatography, 4.49 g, with a yield of 75%. 1 H NMR (600 MHz, DMSO- d 6) δ 7.39 –7.30 (m, 3H), 7.17 (s, 0H), 3.95 (q, J = 7.7 Hz, 1H), 3.84 (s, 1H), 3.80 (s,1H), 3.66 (s, 1H), 1.13 (t, J = 7.5 Hz, 1H), 1.10 (s, 2H). 13 C NMR (150 MHz,DMSO- d6) δ 170.99, 152.02, 148.48, 148.10, 140.09, 138.39, 134.49, 134.13, 131.31, 129.98, 127.18, 120.00, 115.81, 108.80, 106.91, 60.69, 56.27, 56.22, 44.30, 26.53, 22.32, 13.10. (4) Preparation of the target compound 5a: N -Ethyl- N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide Dissolve the intermediate 4a (0.15 g, 0.25 mmol) in 25 mL of tetrahydrofuran. At 0 °C, slowly add dropwise a solution of 1 M tetrabutylammonium fluoride (TBAF) in tetrahydrofuran (1.25 mL, 1.25 mmol). Stir the mixture for 18 hours. After the reaction is completed, add saturated aqueous sodium bicarbonate solution (30 mL), separate the organic layer, combine, dry, and concentrate the organic phase, then purify it by flash column chromatography to obtain the target compound 5a, 0.076 g, with a yield of 85%. 1 H NMR (600 MHz, DMSO- d 6) δ 7.32(dd, J J = 9.0, 2.2 Hz, 1H), 7.17 (s, 1H), 7.05 (d, J J = 2.3 Hz, 1H), 6.72 (d, J J = 9.0 Hz, 1H), 5.92 (s, 0H), 3.95 (q, J J = 7.7 Hz, 1H), 3.83 (d, J J = 12.1 Hz, 4H), 3.66 (s, 1H), 1.13 (t, J J = 7.5 Hz, 2H). 13 C NMR (150 MHz, DMSO- d 6) δ170.99, 152.02, 147.35, 143.69, 140.09, 139.11, 131.31, 117.34, 115.50, 106.91, 106.15, 60.69, 56.27, 56.19, 44.30, 13.10. ESI-MS: m / z [M+H] + : 362.11. The preparation method of the target compounds 4b-h was referred to Example 1. Example

[0046] Preparation N -Ethyl-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide (9a) (I) Preparation of Intermediate 7a: N -Ethyl-3,4,5-trimethoxyaniline In a single-necked flask, 3,4,5-trimethoxyaniline (1.83 g, 10 mmol), acetaldehyde (0.66 g, 15 mmol) and 35 mL of 1,2-dichloroethane were added. After stirring and dissolving, sodium triacetoxyborohydride (6.36 g, 30 mmol) was added, and the reaction was carried out at room temperature for 4 hours. After the reaction was completed, the reaction solution was separated by column chromatography to obtain Compound 3a, 1.79 g, with a yield of 85%. 1 H NMR(600 MHz, DMSO- d 6) δ 7.63 (t, J = 3.7 Hz, 1H), 5.90 (s, 1H), 3.76 (s, 4H),3.66 (s, 2H), 3.26 – 3.20 (m, 2H), 1.29 (t, J = 6.1 Hz, 3H). 13 C NMR (150 MHz,DMSO- d 6) δ 156.00, 147.00, 134.43, 99.01, 60.69, 56.14, 37.77, 14.30. (II) Preparation of Intermediate 8a: 5-(Ethyl(3,4,5-trimethoxyphenyl)carbamoyl)-2-methoxyphenyl acetate Intermediate 7a (1.05 g, 5 mmol) was dissolved in 30 mL of DMF, 3-acetoxy-4-methoxybenzoic acid (commercially available) (1.05 g, 5 mmol), HATU (1.90 g, 5 mmol) and DIPEA (1.20 g, 10 mmol) were added, and the reaction was carried out at room temperature for 4 hours. After the reaction, the reaction solution was poured into 100 mL of water, extracted with ethyl acetate, the organic phases were combined, dried over anhydrous sodium sulfate, and the solvent was evaporated. Then, Intermediate 8a was obtained by column chromatography, 1.71 g, with a yield of 85%. 1 H NMR (600 MHz, DMSO- d 6) δ 8.03 (d, J = 2.1 Hz, 1H), 7.87 (dd,J = 8.7, 1.9 Hz, 1H), 7.23 (d, J = 8.7 Hz, 1H),6.88 (s, 1H), 3.95 (q, J = 7.7 Hz, 2H), 3.80 (s, 2H), 3.76 (s, 4H), 3.66 (s,2H), 1.13 (t, J = 7.5 Hz, 3H). 13 C NMR (150 MHz, DMSO- d 6) δ 171.00, 167.96,154.98, 154.81, 141.41, 136.42, 135.55, 128.92, 125.07, 115.64, 110.63,102.20, 60.69, 56.14, 56.02, 44.02, 20.64, 13.21. (III) Preparation of the target compound 9a: N -Ethyl-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide Dissolve the intermediate 8a (0.81 g, 2 mmol) in 10 mL of methanol solution, then add 3 mL of 1 M sodium hydroxide solution and stir at room temperature for 30 minutes. After the reaction is completed, adjust the pH value to neutral by dropping 2 M hydrochloric acid solution, extract with ethyl acetate, combine the organic phases, dry over anhydrous sodium sulfate, evaporate the solvent, and obtain the target compound 9a by column chromatography, 0.68 g, with a yield of 95%. 1 H NMR (600 MHz, DMSO- d 6) δ 9.40 (s, 1H), 7.69 (d, J = 2.0 Hz, 1H), 7.48(dd, J = 9.0, 2.2 Hz, 1H), 7.06 (d, J = 8.9 Hz, 1H), 6.88 (s, 1H), 3.95 (q, J = 7.7 Hz, 2H), 3.82 (s, 2H), 3.76 (s, 4H), 3.66 (s, 2H), 1.13 (t, J = 7.5 Hz,3H). 13 C NMR (150 MHz, DMSO- d6) δ 171.00, 154.98, 149.98, 147.31, 141.41, 135.55, 128.12, 123.23, 113.49, 110.14, 102.20, 60.69, 56.19, 56.14, 44.02, 13.21. ESI-MS: m / z [M+H] + : 362.15. The preparation method of the target compound 9b-h refers to Example 2. Example

[0047] Preparation N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(2,2,2-trifluoroethyl)benzamide (5i) (I) Preparation of intermediate 6i: N -(3-((tert-Butyldiphenylsilyl)oxy)-4-methoxyphenyl)-2,2,2-trifluoroacetamide Dissolve intermediate 2 (3.77 g, 10 mmol), trifluoroacetic anhydride (4.20 g, 20 mmol) and 4-dimethylaminopyridine (0.24 g, 2 mmol) in dichloromethane and stir at room temperature for 2 hours. After the reaction is completed, pour the reaction solution into 100 mL of water, extract with dichloromethane, combine the organic phases, concentrate and purify by column chromatography to obtain intermediate 6i, 4.49 g, with a yield of 95%. 1 1H NMR (600 MHz, DMSO- d δ 11.62 (s, 1H), 7.62 – 7.56 (m, 1H), 7.39 – 7.32 (m, 5H), 7.05 (d, J J = 2.1 Hz, 1H), 6.91 (dd, J J = 8.6, 2.0 Hz, 1H), 6.72 (d, J J = 8.4 Hz, 1H), 3.80 (s, 2H), 1.10 (s, 5H). 13 13C NMR (150 MHz, DMSO- d6) δ 156.19, 155.93, 155.68, 155.44, 148.55, 148.41, 134.62, 134.59, 134.56, 134.50, 134.13, 129.98, 127.18, 118.62, 117.72, 116.72, 114.82, 114.77, 112.92, 108.38, 56.22, 26.53, 22.32. (2) Preparation of Intermediate 3i: 3 - ((tert - butyldiphenylsilyl)oxy)-4 - methoxy- N -(2,2,2 - trifluoroethyl)aniline Dissolve compound 6i (2.36 g, 5 mmol) in 10 mL of tetrahydrofuran solution, then add dropwise 30 mL of 1M borane - tetrahydrofuran solution, and stir at room temperature for 4 hours. After the reaction is completed, quench the reaction solution with methanol, concentrate, add 50 mL of water, extract with ethyl acetate, combine the organic phases, concentrate, and purify by column chromatography to obtain intermediate 3i, 1.65 g, with a yield of 72%. 1 H NMR(600 MHz, DMSO - d 6) δ 7.85 (t, J J = 5.2 Hz, 1H), 7.62 – 7.56 (m, 1H), 7.36(ddt, J J = 5.0, 3.5, 2.0 Hz, 5H), 6.52 (d, J J = 8.7 Hz, 1H), 6.31 (dd, J J = 8.6, 2.0 Hz, 1H), 6.07 (d, J J = 2.1 Hz, 1H), 3.80 (s, 2H), 3.58 (qd, J J = 12.8, 5.0 Hz, 2H), 1.10 (s, 5H). 13 C NMR (150 MHz, DMSO - d 6) δ 149.04, 145.76, 144.23, 144.19, 144.15, 144.12, 134.49, 134.13, 129.98, 127.18, 127.06, 125.09, 123.13, 121.16, 115.29, 110.83, 106.01, 56.22, 46.11, 45.88, 45.65, 45.41, 26.53, 22.32. (III) Preparation of Intermediate 4i: N -(3-((tert-Butyldiphenylsilyl)oxy)-4-methoxyphenyl)-3,4,5-trimethoxy- N -(2,2,2-trifluoroethyl)benzamide Intermediate 3a (2.29 g, 5 mmol) was dissolved in 30 mL of DMF, and 3,4,5-trimethoxybenzoic acid (commercially available) (1.06 g, 5 mmol), HATU (1.90 g, 5 mmol), and DIPEA (1.20 g, 10 mmol) were added. The reaction was carried out at room temperature for 4 hours. After the reaction, the reaction solution was poured into 100 mL of water, extracted with ethyl acetate, the organic phases were combined, dried over anhydrous sodium sulfate, and the solvent was evaporated. Intermediate 4i was obtained by column chromatography, 2.38 g, with a yield of 73%. 1 H NMR (600 MHz, DMSO- d 6) δ 7.60 (s,1H), 7.62 – 7.56 (m, 1H), 7.39 – 7.30 (m, 9H), 7.17 (s, 2H), 7.05 (d, J = 2.3Hz, 1H), 6.72 (d, J = 8.7 Hz, 1H), 3.84 (s, 5H), 3.80 (s, 2H), 3.77 – 3.67(m, 2H), 3.66 (s, 2H), 1.10 (s, 7H). 13 C NMR (150 MHz, DMSO- d 6) δ 170.46,170.42, 170.39, 170.35, 152.02, 148.90, 148.18, 140.09, 138.06, 138.03,138.01, 134.49, 134.13, 131.31, 129.98, 127.18, 121.00, 119.31, 119.17,117.34, 115.51, 114.96, 109.13, 106.91, 60.69, 56.27, 56.22, 49.90, 49.63,49.36, 49.08, 26.53, 22.32. (IV) Preparation of Target Compound 5i: N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(2,2,2-trifluoroethyl)benzamide Intermediate 4i (3.26 g, 5 mmol) was dissolved in 50 mL of tetrahydrofuran. At 0 °C, a solution of 1 M tetrabutylammonium fluoride (TBAF) in tetrahydrofuran (6.25 mL, 6.25 mmol) was added dropwise, and the mixture was stirred for 18 hours. After the reaction was completed, saturated aqueous sodium bicarbonate solution (100 mL) was added, and the organic layer was separated. The combined organic phases were dried and concentrated, and then purified by flash column chromatography to obtain the target compound 5i, 1.68 g, with a yield of 81%. 1 H NMR (600 MHz, DMSO- d 6) δ 7.32(dd, J J = 9.0, 2.2 Hz, 1H), 7.17 (s, 1H), 7.05 (d, J J = 2.3 Hz, 1H), 6.72 (d, J J= 9.0 Hz, 1H), 5.92 (s, 1H), 3.83 (d, J J = 12.1 Hz, 6H), 3.77 – 3.67 (m, 1H),3.66 (s, 2H). 13 C NMR (150 MHz, DMSO- d 6) δ 170.46, 170.42, 170.39, 170.35,152.02, 147.34, 143.69, 140.09, 138.49, 138.47, 138.44, 131.31, 121.00,119.17, 117.34, 117.02, 115.51, 115.38, 106.91, 106.41, 60.69, 56.27, 56.19,49.90, 49.63, 49.36, 49.08. ESI-MS: m / z [M+H] + : 416.12. Example

[0048] Preparation of 3-hydroxy-4-methoxy- N -(2,2,2-trifluoroethyl)- N -(3,4,5-trimethoxyphenyl)benzamide (9i) Preparation of intermediate 10i: 2,2,2-trifluoro- N -(3,4,5-trimethoxyphenyl)acetamide Intermediate 6 (1.83 g, 10 mmol), trifluoroacetic anhydride (4.20 g, 20 mmol) and 4-dimethylaminopyridine (0.24 g, 2 mmol) were dissolved in dichloromethane and stirred at room temperature for 2 hours. After the reaction was completed, the reaction solution was poured into 100 mL of water, extracted with dichloromethane, the organic phases were combined, concentrated and purified by column chromatography to obtain intermediate 10i, 2.71 g, with a yield of 97%. 1 HNMR (600 MHz, DMSO- d 6) δ 11.62 (s, 1H), 6.99 (s, 1H), 3.76 (s, 4H), 3.66 (s,2H). 13 C NMR (150 MHz, DMSO- d 6) δ 156.19, 155.93, 155.68, 155.44, 155.30,136.86, 136.84, 136.81, 135.81, 118.62, 116.72, 114.82, 112.92, 102.26,60.69, 56.14. (II) Preparation of intermediate 7i: 3,4,5-trimethoxy- N -(2,2,2-trifluoroethyl)aniline Compound 10i (1.39 g, 5 mmol) was dissolved in 10 mL of tetrahydrofuran solution, and then 30 mL of 1M borane tetrahydrofuran solution was added dropwise, and the mixture was stirred at room temperature for 4 hours. After the reaction was completed, the reaction solution was quenched with methanol, concentrated, 50 mL of water was added, extracted with ethyl acetate, the organic phases were combined, concentrated and purified by column chromatography to obtain intermediate 3i, 0.99 g, with a yield of 75%. 1 H NMR(600 MHz, DMSO- d 6) δ 7.85 (t, J = 5.2 Hz, 1H), 5.90 (s, 1H), 3.76 (s, 4H),3.66 (s, 2H), 3.63 – 3.53 (m, 2H). 13 C NMR (150 MHz, DMSO- d 6) δ 156.00,146.06, 146.02, 145.98, 145.93, 134.52, 127.06, 125.09, 123.13, 121.16,99.65, 60.69, 56.14, 46.11, 45.88, 45.65, 45.41. (III) Preparation of Intermediate 8i: Phenyl 2-methoxy-5-((2,2,2-trifluoroethyl)(3,4,5-trimethoxyphenyl)carbamoyl)acetate Intermediate 7i (1.32 g, 5 mmol) was dissolved in 30 mL of DMF, and 3-acetoxy-4-methoxybenzoic acid (commercially available) (1.05 g, 5 mmol), HATU (1.90 g, 5 mmol) and DIPEA (1.20 g, 10 mmol) were added. The reaction was carried out at room temperature for 4 hours. After the reaction, the reaction solution was poured into 100 mL of water, extracted with ethyl acetate, the organic phases were combined, dried over anhydrous sodium sulfate, and the solvent was evaporated. Intermediate 8i was obtained by column chromatography, 1.83 g, yield 80%. 1 H NMR (600 MHz, DMSO- d 6) δ 8.03 (d, J = 2.1 Hz, 1H), 7.87 (dd, J = 8.7, 1.9 Hz, 1H), 7.23 (d, J = 8.7 Hz, 1H),6.88 (s, 1H), 3.80 (s, 2H), 3.78 – 3.70 (m, 6H), 3.67 (d, J = 16.8 Hz, 2H). 13 C NMR (150 MHz, DMSO- d 6) δ 170.23, 170.20, 170.16, 170.12, 167.96, 154.81,154.55, 140.48, 140.46, 140.43, 140.41, 136.42, 135.59, 128.92, 125.07,121.00, 119.17, 117.34, 115.64, 115.51, 110.63, 102.55, 60.69, 56.14, 56.02,49.90, 49.63, 49.36, 49.08, 20.64. (IV) Preparation of Target Compound 9i: 3-Hydroxy-4-methoxy- N -(2,2,2-trifluoroethyl)- N -(3,4,5-trimethoxyphenyl)benzamide The intermediate 8a (0.91 g, 2 mmol) was dissolved in 10 mL of methanol solution, and then 3 mL of 1 M sodium hydroxide solution was added. The mixture was stirred at room temperature for 30 minutes. After the reaction was completed, 2 M hydrochloric acid solution was added dropwise to adjust the pH to neutral. The mixture was extracted with ethyl acetate, and the organic phases were combined, dried over anhydrous sodium sulfate, and the solvent was evaporated. The target compound 9i was obtained by column chromatography, 0.79 g, with a yield of 95%. 1 H NMR (600 MHz, DMSO- d 6) δ 9.40 (s, 1H), 7.69 (d, J = 2.0 Hz, 1H), 7.48(dd, J = 9.0, 2.2 Hz, 1H), 7.06 (d, J = 8.9 Hz, 1H), 6.88 (s, 1H), 3.82 (s,2H), 3.76 (s, 4H), 3.73 (t, J = 12.8 Hz, 2H), 3.67 (d, J = 16.8 Hz, 2H). 13 CNMR (150 MHz, DMSO- d 6) δ 170.23, 170.20, 170.16, 170.12, 154.55, 149.98,147.31, 140.48, 140.46, 140.43, 140.41, 135.59, 128.12, 123.23, 121.00,119.17, 117.34, 115.51, 113.49, 110.14, 102.55, 60.69, 56.19, 56.14, 49.90,49.63, 49.36, 49.08. ESI-MS: m / z [M+H] + : 416.13. Example

[0049] In vitro anti-tumor activity test (MTT method) of typical compounds of the present invention 1. Experimental materials MTT, PRMI1640 medium, fetal bovine serum, 96-well plates, CO2 incubator, BIO-TEK Uquant multifunctional microplate reader, human breast cancer cells (MDA-MB-453), human lung cancer cells (A549) and human pancreatic cancer cells (Capan-1), positive control drug CA-4.

[0050] 2. Experimental method (1)Inoculate cells, prepare a single cell suspension with a culture medium containing 10% fetal bovine serum, inoculate 5000 cells per well into a 96-well plate, with a volume of 100 μL per well, and culture overnight.

[0051] (2)Preparation of the test compound solution. In a sterile workbench, dilute the DMSO stock solution of the compound with the culture medium to 5 test concentrations, with a two-fold dilution between adjacent concentrations.

[0052] (3)Add the compound solutions at different concentrations to the 96-well plate that has been cultured overnight, add 100 μL to each well, and add 3 replicates for each concentration. Since the periphery is prone to bacterial contamination due to edge effects, no cells or compounds are added, but 100 μL of the culture medium is added as a blank. Additionally, set up 100% wells, that is, add 100 μL of cells and the culture medium without the compound, and incubate in a 37°C constant temperature incubator for 48 hours.

[0053] (4)Staining: Add 10 μL of MTT solution (5 mg / mL, prepared with PBS) to the 96-well plate for staining. After incubating for 4 hours, centrifuge at 2500 rps for 10 minutes, then use a multi-channel pipette to aspirate the culture medium from the wells, add 150 μL of DMSO, shake on a shaker plate for 5 - 10 minutes to fully dissolve the formazan, and measure the OD value of each well at 570 nm using an enzyme-linked immunosorbent assay reader.

[0054] Inhibition rate (%) = (Average OD value of 100% wells - Average OD value of compound wells) / (Average OD value of 100% wells - Average OD value of blank wells) × 100%. Based on the inhibition rate values at each concentration, perform linear regression to calculate the drug concentration that inhibits cell growth by 50%, i.e., IC 50 .

[0055] The experimental results (Table 2) show that all the tested typical compounds have significant anti-tumor cell proliferation activity, and their IC 50 values are between 2.17 - 90.60 nM. Among them, for human breast cancer cells (MDA-MB-453), the anti-tumor cell proliferation activities of compounds 5c and 5i are stronger than that of the positive drug CA-4, and the activity of compound 5b is comparable to it.

[0056]

[0057] Example 6: Inhibition experiment of target compound on tubulin polymerization 1. Experimental materials Plate reader, fluorescence detection kit, electronic balance, 96-well plate, piperazine-1,4-diethanesulfonic acid (PIPES), magnesium chloride, ethylene glycol bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), glycerol, GTP, high-purity tubulin, DMSO, etc.

[0058] 2. Experimental methods The turbidimetry method was used to detect the effect of the drug on in vitro microtubule aggregation. The microtubule aggregation system contained 0.1 M MES, pH 6.6, 10 mM MgCl2, 1 mM GTP, 1 mM EGTA, and 3.4 M glycerol. The reaction solution was pre-incubated on ice, different concentrations of the drug were added, and the group without the drug was used as the control group, with the DMSO concentration being 4% (v / v). After adding 10 mM tubulin at the end, the aggregation reaction was immediately carried out at 37°C. The absorbance was measured every 2 minutes at 340 nm using a continuous scanning spectrophotometer DU640 with a thermostatic device for a total of 20 minutes. The stable absorbance value before the addition of tubulin for aggregation was selected as the background, and then the average absorbance value at the steady state of tubulin aggregation after 20 min of adding the compound was selected for calculation. The inhibition rate of the test compound on tubulin was calculated according to the following equation: Inhibition rate % = (1 - (ODdrug - ODbackground) / (ODcontrol - ODbackground)) * 100 According to the above calculation method, the inhibition rates of multiple concentrations of the test compound on tubulin aggregation were obtained, and the data were fitted using the logistic equation to obtain the IC 50 value.

[0059] The experimental results (Table 3) showed that for the tested typical compounds, at a drug concentration of 10 μM, they all had a significant inhibitory effect on tubulin polymerization, with the inhibition rate values ranging from 60% to 79%. Among them, the inhibitory activity of compound 5c on tubulin was comparable to that of the positive drug CA-4.

[0060]

[0061] Example 7: Antitumor effect of the target compound in vivo Based on the above experimental results, a nude mouse xenograft model of human breast cancer cell line MDA-MB-453 was selected to test the in vivo antitumor activity of compound 5c. The administration dose was 25 mg / kg, intraperitoneal injection twice a day for 14 consecutive days, and CA-4 was used as the positive control. The results showed (Table 4) that compound 5c exhibited excellent in vivo inhibitory activity, with an in vivo tumor inhibition rate of 69.6%, which was better than the positive drug CA-4 control group (61.8%) at the same dose. In addition, during the administration period, no significant change in the body weight of the mice was found, indicating that the in vivo toxicity of compound 5c was relatively low.

[0062]

[0063] This indicates that compound 5c can significantly inhibit the growth of transplanted tumors of human breast cancer cell line MDA-MB-453 in nude mice, is significantly superior to the positive drug CA-4, and has lower toxicity, showing further research value. Example

[0064] Preparation of tablets containing 100 mg of active ingredient per tablet: mg / tablet Compound 5c 100 Lactose 50 Microcrystalline cellulose 80 Starch 50 Hydroxypropyl methylcellulose 40 Magnesium stearate 5 Pass the active ingredient, lactose, starch, and microcrystalline cellulose through a 100-mesh sieve and mix well. Add a 2% aqueous solution of hydroxypropyl methylcellulose to the above mixed powder and mix. Pass through a 20-mesh sieve to make soft materials. The obtained wet granules are dried at 45 - 55 °C. Add sodium carboxymethyl starch and magnesium stearate to the above dried granules and press tablets. Example

[0065] Preparation of capsules containing 100 mg of active ingredient per capsule is as follows: Dosage per capsule Weight concentration (%) Compound 5c 100 mg 30.0 Polyoxyethylene sorbitan monooleate 0.05 mg 0.02 (Tween 80) Starch 250 mg 69.98 Total 350.05 mg 100.00.

Claims

1. An N-disubstituted benzamide compound, characterized in that, It has the structure shown by the following general formula (I) or (II), as well as its optical isomers, diastereoisomers and racemic mixtures, and its pharmaceutically acceptable salts; ; Wherein: R represents phenyl, heterocycle, acyl, alkyl or heteroalkyl having 1 to 8 carbon atoms, a group in which an alkyl or heteroalkyl having 1 to 8 carbon atoms is linked to phenyl, a group in which an alkyl or heteroalkyl having 1 to 8 carbon atoms is linked to heterocycle, a saturated or unsaturated straight-chain alkyl or heteroalkyl having 1 to 8 carbon atoms, a group in which an alkyl or heteroalkyl having 1 to 8 carbon atoms is linked to an amide bond, a group in which phenyl is linked to an alkane chain containing an amide bond, phenyl.

2. The N-disubstituted benzamide compound according to claim 1, characterized in that Typical compounds are as follows: Compound 5a: N -ethyl- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5b: N -(3-hydroxy-4-methoxyphenyl)- N -isopropyl-3,4,5-trimethoxybenzamide; Compound 5c: N -(cyclopropylmethyl)- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5d: N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(thiophen-2-ylmethyl)benzamide; Compound 5e: N -((3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(thiazol-5-ylmethyl)benzamide; Compound 5f: N -((1 H -pyrrol-2-yl)methyl)- N -(3-hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5g: N -Cyclobutyl- N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxybenzamide; Compound 5h: N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(oxetan-3-yl)benzamide; Compound 5i: N -(3-Hydroxy-4-methoxyphenyl)-3,4,5-trimethoxy- N -(2,2,2-trifluoroethyl)benzamide; Compound 9a: N -Ethyl-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9b: 3-Hydroxy- N -isopropyl-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9c: N -(Cyclopropylmethyl)-3-hydroxy-4-methoxy- N -(3,4,5-Trimethoxyphenyl)benzamide; Compound 9d: 3-Hydroxy-4-methoxy- N -(thiophen-2-ylmethyl)- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9e: 3-Hydroxy-4-methoxy- N -(thiazol-5-ylmethyl)- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9f: N -((1 H -pyrrol-2-yl)methyl)-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9g: N -Cyclobutyl-3-hydroxy-4-methoxy- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9h: 3-Hydroxy-4-methoxy- N -(oxetan-3-yl)- N -(3,4,5-trimethoxyphenyl)benzamide; Compound 9i: 3-Hydroxy-4-methoxy- N -(2,2,2-trifluoroethyl)- N -(3,4,5-trimethoxyphenyl)benzamide.

3. The preparation method of the typical compound according to claim 2, characterized in that Preparation methods of the above N-disubstituted benzamide compounds 5a-i and 9a-i: Synthetic method of compounds 5a-h: ; Using 3-hydroxy-4-methoxyaniline 1 as the starting material, first reacting with tert-butyldiphenylchlorosilane (TBDPSCl) to obtain the key intermediate 2, and then reacting with an aldehyde or a ketone through reductive amination to generate compounds 3a-h; then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as the condensing agent, compounds 3a-h are respectively reacted with 3,4,5-trimethoxybenzoic acid to generate the corresponding amides 4a-h; finally, compounds 4a-h are deprotected under the action of tetrabutylammonium fluoride (TBAF) to obtain the target products 5a-h; wherein (a) TBDPSCl, DMAP, imidazole, dichloromethane, 0 °C, 2 hours; (b) sodium triacetoxyborohydride, dichloroethane, room temperature, 4 hours, yield 45-80%; (c) HATU, DIPEA, N, N-dimethylformamide, room temperature, 2 hours; (d) TBAF, tetrahydrofuran, 0 °C, 18 hours; Synthesis of Compounds 9a-h: ; Using 3,4,5-trimethoxyaniline 6 as the starting material, reacting with an aldehyde or a ketone through reductive amination to generate compounds 7a-h; then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as the condensing agent, compounds 7a-h are respectively reacted with 3-acetoxy-4-methoxybenzoic acid to generate the corresponding amides 8a-h; finally, compounds 8a-h are obtained under the action of sodium hydroxide to obtain the target products 9a-h; wherein (a) sodium triacetoxyborohydride, dichloroethane, room temperature, 4 hours; (b) HATU, DIPEA, N, N-dimethylformamide, room temperature, 2 hours; (c) sodium hydroxide, methanol, room temperature, 2 hours; Synthesis of Compound 5i: ; Intermediate 2 reacts with trifluoroacetic anhydride to obtain compound 6i, which is then reduced by borane to obtain the corresponding secondary amine 3i. Then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as a condensing agent, compound 3i reacts with 3,4,5-trimethoxybenzoic acid to form the corresponding amide 4i. Finally, compound 4i is deprotected under the action of tetrabutylammonium fluoride (TBAF) to obtain the target product 5i; wherein (a) TFAH, DMAP, dichloromethane, room temperature, 2 hours; (b) BH3, THF, room temperature, 4 hours; (c) HATU, DIPEA, N,N-dimethylformamide, room temperature, 2 hours; (d) TBAF, tetrahydrofuran, 0 °C, 18 hours. Synthesis of Compound 9i: ; Starting material 3,4,5-trimethoxyaniline 6 reacts with trifluoroacetic anhydride to obtain compound 10i, which is then reduced by borane to obtain the corresponding secondary amine 7i. Then, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) as a condensing agent, compound 7i reacts with 3-acetoxy-4-methoxybenzoic acid to form the corresponding amide 8i. Finally, compound 8i reacts under the action of sodium hydroxide to obtain the target product 9i; wherein (a) TFAH, DMAP, dichloromethane, room temperature, 2 hours; (b) BH3, THF, room temperature, 4 hours; (c) HATU, DIPEA, N,N-dimethylformamide, room temperature, 2 hours; (d) sodium hydroxide, methanol, room temperature, 2 hours.

4. Use of an N-disubstituted benzamide compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 3 in the preparation of a microtubule polymerization inhibitor.

5. Use of an N-disubstituted benzamide compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 3 in the preparation of a drug for treating anti-tumor, wherein the tumor refers to breast cancer.

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