Benzamide-oxadiazole skeleton compound as well as preparation method and application thereof

Abstract

The invention discloses a compound with a benzamide-oxadiazole skeleton as well as a preparation method and application thereof. The structure of the compound is shown in the specification. According to the present invention, butyrylcholine esterase inhibition activity, Nrf2 activation activity, in vitro pharmacodynamic experiment and Morris water maze experiment are adopted as carriers to evaluate the treatment of Alzheimer's disease (especially moderate and severe Alzheimer's disease) by using the compound represented by the general formula I, and the results show that the compound has good in vitro and in vivo activity and extremely high selectivity; the compound can be used as a candidate lead compound for further development of an anti-Alzheimer's disease effect by selectively inhibiting butyrylcholine esterase and activating Nrf2.

Description

Technical Field

[0001] This invention relates to the chemical and pharmaceutical industries, and particularly to benzamide-oxadiazole dual-target modulators, their preparation methods, and applications. Background Technology

[0002] Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory decline, cognitive impairment, and behavioral abnormalities. Its core pathological features include β-amyloid protein (Aβ) plaque deposition in the brain, neurofibrillary tangles formed by highly phosphorylated Tau protein, synaptic dysfunction, and depletion of neurotransmitters, particularly acetylcholine (ACh). It is estimated that there are currently over 50 million AD patients worldwide; with the increasing aging of the global population, this number is projected to exceed 150 million by 2050, making AD a major challenge urgently needing to be addressed in global public health. As of 2025, the U.S. Food and Drug Administration (FDA) had approved six drugs for the treatment of Alzheimer's disease (AD), specifically categorized as follows: (1) cholinesterase inhibitors: donepezil, rivastigmine, and galantamine; (2) N-methyl-D-aspartate (NMDA) receptor antagonists: memantine; and (3) Aβ monoclonal antibodies: lecanemab and donanemab. Among these, cholinesterase inhibitors and NMDA receptor antagonists can only improve patients' cognitive impairment symptoms in the short term, and their overall therapeutic effect is far from clinically expected. Although Aβ monoclonal antibodies are considered a breakthrough in the treatment mechanism of AD, clinical research data indicate that these drugs may cause adverse reactions such as cerebral edema and cerebral hemorrhage, and their safety risks have sparked widespread controversy in the industry. In summary, existing AD treatment options cannot meet the huge clinical demand in the treatment of this disease, and there is an urgent need to develop new therapeutic drugs that can intervene in the deep pathological mechanisms of AD.

[0003] Multi-target directed ligands (MTDLs) are single drug molecule that can simultaneously and precisely target multiple disease-related biological targets. They overcome the limitations of the traditional "one drug, one target" strategy, are applicable to diseases with complex mechanisms, and achieve more comprehensive efficacy by synergistically regulating multiple pathogenic pathways, while reducing the risk of drug interactions and simplifying medication regimens. Considering the complex pathological mechanisms of Alzheimer's disease (AD) and the interactions between multiple factors, multi-target therapy has become a new direction in drug design. In the later stages of AD, the expression and activity of beta-cholesterol (BChE) significantly increase, exacerbating cholinergic dysfunction and affecting patient cognition. Specific targeting and inhibition of BChE is considered a highly attractive AD treatment strategy because it can simultaneously improve cholinergic function, counteract amyloidosis and tau pathology, and exert neuroprotective effects. Oxidative stress is a core factor and an essential stage in the complex pathogenesis of AD—it not only connects pathways such as amyloid, tau, neuroinflammation, and metal ions, but also directly mediates neuronal damage. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a core transcription factor regulating cellular anti-oxidative stress and anti-inflammatory responses. Activation of Nrf2 can induce the expression of various protective genes, effectively reduce oxidative damage and inflammation, and play a crucial role in maintaining mitochondrial function and metal ion homeostasis. Given Nrf2's central regulatory role, developing drugs that target and regulate Nrf2 activity has become an important strategy for intervening in the pathological progression of Alzheimer's disease (AD).

[0004] Ferroptosis is a specific form of programmed cell death driven by lipid peroxidation and dependent on iron ions. The phospholipids of polyunsaturated fatty acids (PUFAs) (PUFA-PL) are core components of the cell membrane and are highly susceptible to ROS-induced peroxidation. PUFA-PL peroxidation disrupts the integrity of the phospholipid bilayer; when excessive lipid hydroperoxides cannot be cleared, abnormal membrane permeability occurs, ultimately leading to cell membrane rupture. Nrf2 activators can drive the expression of genes related to glutathione (GSH) synthesis, increase intracellular GSH levels, activate the GSH-GPX4 axis, and reduce toxic phospholipid hydroperoxides (PUFA-PL-OOH) to non-reactive, non-lethal phosphatidyl alcohols (PUFA-PL-OH), thus blocking the accumulation of lipid peroxidation and exerting a ferroptosis defense effect. Studies have shown that BChE inhibitors exhibit Nrf2 activating activity and can upregulate Nrf2 expression. Furthermore, inhibiting BChE can block Aβ oligomerization and reduce the production of oxidative stress factors such as ROS and hydrogen peroxide. In summary, BChE inhibition and Nrf2 activation can synergistically regulate the GSH-GPX4 signaling axis, thereby inhibiting ferroptosis, exerting a neuroprotective effect, and significantly improving AD pathology. Summary of the Invention

[0005] Objective of this invention: The objective of this invention is to provide novel compounds with a benzamide-oxadiazole structure exhibiting good in vitro and in vivo activity and high selectivity. These compounds simultaneously and efficiently inhibit BChE and activate the Nrf2 signaling pathway, achieving a dual synergistic pharmacological effect. This structural framework has been demonstrated to possess excellent BChE inhibitory activity and selectivity, providing a powerful technical solution to overcome the limitations of current single-target AD treatments. Another objective of this invention is to provide a method for preparing the aforementioned compound and its uses.

[0006] Technical solution: The compound with the benzamide-oxadiazole skeleton or its pharmaceutically acceptable salt described in this invention has the following structure as shown in general formula I:

[0007]

[0008] in,

[0009] R1 represents ortho, meta, and para phenyl groups; R2 represents hydrogen, C 1～6 Alkyl groups, alkyl chains with a length of C 1～6 The phenylalkyl group, substituted or unsubstituted phenyl group; the substitution is selected from halogen, nitro, -OC 1～4 Alkyl, C 1～6 Alkyl, halogen-substituted -OC 1～4 Alkyl, cyclopropyl, morpholino.

[0010] The compound with the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof,

[0011] R1 represents

[0012] R2 represents hydrogen, C 1～6 Alkyl groups, alkyl chains with a length of C 1-5 The phenylalkyl group, substituted or unsubstituted phenyl group; the substitution is selected from halogen, nitro, methoxy, C 1～4 Alkyl, trifluoromethoxy, cyclopropyl, morpholino.

[0013] The compound with the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof is any one of the following compounds or a pharmaceutically acceptable salt thereof:

[0014]

[0015]

[0016]

[0017]

[0018] The compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof, wherein the pharmaceutically acceptable salt is a salt formed by the compound and any one of the following acids: hydrochloric acid, hydrogen bromide, sulfuric acid, carbonic acid, oxalic acid, citric acid, malic acid, succinic acid, tartaric acid, phosphoric acid, lactic acid, pyruvic acid, acetic acid, maleic acid, methanesulfonic acid, citric acid, benzenesulfonic acid, p-toluenesulfonic acid, or ferulic acid.

[0019] The preparation method of the compound with the benzamide-oxadiazole skeleton or its pharmaceutically acceptable salt, wherein the preparation method of the compound represented by general formula I includes the following steps:

[0020]

[0021] The method for preparing the compound with the benzamide-oxadiazole skeleton or its pharmaceutically acceptable salt, specifically step a, involves using... The starting material is dissolved in acetonitrile and reacted with potassium carbonate and diethylamine at 40-70℃ to obtain the intermediate. Step b is specifically as follows The intermediate was obtained by reduction.

[0022] The method for preparing the compound with the benzamide-oxadiazole skeleton or its pharmaceutically acceptable salt, characterized in that step c specifically involves preparing the intermediate... Intermediates were obtained by reacting ortho-, meta-, and para-substituted cyanobenzoyl chlorides and cesium carbonate in N,N'-dimethylformamide at 40-60°C with the solutions. R1 is defined as described above.

[0023] The method for preparing the compound with the benzamide-oxadiazole skeleton or its pharmaceutically acceptable salt, specifically step d, is as follows: The intermediate was obtained by refluxing hydroxylamine hydrochloride and potassium carbonate in anhydrous ethanol at 70-90°C. Step e is specifically as follows The target compound was obtained by amide condensation with R2-COOH.

[0024] R1 and R2 are defined as described above.

[0025] Pharmaceutical compositions comprising compounds of the benzamide-oxadiazole skeleton or pharmaceutically acceptable salts thereof and pharmaceutically acceptable carriers thereof.

[0026] Use of the compound with the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof in the preparation of a medicament for the prevention or treatment of Alzheimer's disease.

[0027] Furthermore, the pharmaceutical composition is formulated as tablets, capsules, powders, syrups, liquids, suspensions, or injections.

[0028] Beneficial Effects: This invention provides a novel benzamide-oxadiazole derivative represented by general formula I. Evaluation of the following key technical indicators confirmed the therapeutic potential of the compound in treating Alzheimer's disease (AD), particularly in moderate to severe AD: target assay results showed that the compound exhibits good and highly selective inhibition of BChE and effectively activates the Nrf2 signaling pathway; pharmacodynamic evaluation showed that the preferred compound can activate antioxidant pathways and alleviate oxidative stress; in vivo behavioral evaluations, such as the Morris water maze test, confirmed that administration of the compound significantly improved cognitive dysfunction in AD model animals. Furthermore, the compound of this invention is expected to exert a neuroprotective effect by synergistically regulating ferroptosis, achieving the therapeutic goal of delaying disease progression. In summary, the compound of this invention is a highly promising candidate lead compound for combating AD through a dual mechanism (selective inhibition of BChE and activation of Nrf2). Attached Figure Description

[0029] Figure 1 These are the results of a cytotoxicity assay;

[0030] Figure 2 This is the result of a luciferase assay;

[0031] Figure 3 These are the results of lipid peroxide detection under a fluorescence microscope;

[0032] Figure 4 This is the result of Morris's water maze research; Detailed Implementation

[0033] Example 1

[0034] (1) Synthesis of 2-((diethylamino)methyl)benzonitrile (intermediate 1)

[0035] 2-Cyanobenzyl bromide (2 g, 10.2 mmol) was dissolved in acetonitrile, and potassium carbonate (1.41 g, 10.2 mmol) was added. Diethylamine (1.58 mL, 15.3 mmol) was added dropwise while stirring. The reaction was carried out at 60 °C for 2 h. After the reaction was completed by TLC monitoring, the potassium carbonate was removed by hot filtration. The filtrate was evaporated by rotary evaporation to obtain a yellow oily liquid. Ethyl acetate was added, and the mixture was washed three times with water and saturated sodium bicarbonate solution, respectively. The organic layer was collected, dried over anhydrous sodium sulfate, and evaporated by rotary evaporation to obtain intermediate 1. This intermediate was a pale yellow oily liquid with a yield of 85.94% and did not require further purification. 1H NMR (300MHz, DMSO-d6) δ7.64–7.55(m,1H),7.53–7.37(m,2H),7.33–7.22(m,1H),3.51(s,2H),2.43–2.21(m,4H),0.81(t,J=7.1Hz,6H).

[0036] (2) Synthesis of N-(2-(aminomethyl)benzyl)-N-ethylethylamine (intermediate 2)

[0037] Intermediate 1 (1.65 g, 8.76 mmol) was dissolved in tetrahydrofuran and pre-cooled in a cold trap for 10 min. Lithium aluminum hydride (665.24 mg, 17.53 mmol) was slowly added in portions while stirring. After reacting in the cold trap for 0.5 h, the mixture was transferred to room temperature and reacted for 2 h. After the reaction was complete as monitored by TLC, 15% sodium hydroxide solution was slowly added dropwise to the reaction solution under ice bath conditions until no gas was generated. After stirring for 0.5 h, the mixture was filtered through a diatomaceous earth filter. Water was added to the filtrate, and the mixture was extracted with ethyl acetate. The organic layer was collected, dried over anhydrous sodium sulfate, and rotary evaporated to obtain intermediate 2. This intermediate, a pale yellow oily liquid with a yield of 76.92%, requires no further purification and can be used directly in the next reaction. 1 H NMR (300MHz, DMSO-d6) δ7.50–7.42(m,1H),7.40–7.27(m,3H),4.03(s,2H),3.68(s,2H),2.59–2.42(m,4H),1.02(t,J=7.1Hz,6H).

[0038] (3) Synthesis of 3-cyano-N-(2-((diethylamino)methyl)benzyl)benzoyl (intermediate 3a): Intermediate 2 (1.12 g, 5.82 mmol) was dissolved in DMF, and 3-cyanobenzoyl chloride (964.32 mg, 5.82 mmol) and cesium carbonate (1.90 g, 5.82 mmol) were added. The reaction was carried out at 50 °C for 2 h. After the reaction was completed by TLC monitoring, the reaction solution was added dropwise to water while stirring, and a white precipitate was formed. After standing, the precipitate was filtered to obtain intermediate 3a. No further purification was required, and it could be used directly for the next step of the reaction. It was a white solid with a yield of 80.2%. 1 H NMR (300MHz, DMSO-d6) δ9.25(s,1H),8.28(s,1H),8.17(d,J=7.9Hz,1H),8.03(d,J=7.7Hz,1H),7.73(t,J=7 .8Hz,1H),7.42–7.15(m,4H),4.66(d,J=5.5Hz,2H),3.64(s,2H),2.56–2.49(m,4H),0.98(t,J=7.0Hz,6H).

[0039] (4) Synthesis of (Z)-N-(2-((diethylamino)methyl)benzyl)-3-(N'-hydroxyaminoamide)benzoyl (intermediate 4a)

[0040] Intermediate 3a (1.2 g, 3.73 mmol) was dissolved in ethanol, and hydroxylamine hydrochloride (518.85 mg, 7.47 mmol) and potassium carbonate (1.03 g, 7.47 mmol) were added. The mixture was refluxed at 85 °C for 12 h. After the reaction was completed by TLC monitoring, the mixture was filtered while hot. The filtrate was allowed to stand and white crystals precipitated. Intermediate 4a was obtained by filtration, which yielded a white solid with a yield of 60.61%. 1 H NMR (300MHz, DMSO-d6) δ9.71(s,1H),9.13(t,J=5.3Hz,1H),8.15(s,1H),7.87–7.75(m,2H),7.47(t,J=7.8Hz,1H ),7.35–7.16(m,4H),5.88(s,2H),4.63(d,J=5.6Hz,2H),3.64(s,2H),2.56–2.49(m,4H),0.97(t,J=7.1Hz,6H).

[0041] (5) Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0042] 3,4-Difluorobenzoic acid (26.76 mg, 169.27 μmol), 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU, 64.4 mg, 169.27 μmol), and N,N-diisopropylethylamine (DIPEA, 60 μL, 338.6 μmol) were dissolved in N,N'-dimethylformamide and stirred at room temperature for 30 min. After TLC monitoring showed that 3,4-difluorobenzoic acid was activated, intermediate 4a (50 mg, 141.06 μmol) was added to the reaction solution, and the mixture was stirred at room temperature for 2 h. After the reaction was complete, the reaction solution was added dropwise to water while stirring, and a precipitate formed. The precipitate was filtered and dried. The filter cake was dissolved in dimethyl sulfoxide, potassium hydroxide was added, and the mixture was stirred at room temperature for 1 h. After TLC monitoring showed that the reaction was complete, the reaction solution was added dropwise to water while stirring, and the mixture was extracted with ethyl acetate. The organic phase was collected and dried over anhydrous sodium sulfate. Purification by column chromatography (mobile phase: dichloromethane / methanol = 94 / 6) yielded a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 50.58%. 1H NMR (300MHz, DMSO-d6) δ9.42(t,J=5.5Hz,1H),8.46(s,1H),8.20–8.11(m,2H),8.11–8.03(m,1H),8.03–7.96(m,1H),7.78–7.57(m,2H) ),7.38–7.15(m,4H),4.65(d,J=5.4Hz,2H),3.64(s,2H),2.62–2.42(m,4H),0.95(t,J=7.1Hz,6H).HRMS(ESI):found477.2106,calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0043] Example 2

[0044] (1) Synthesis of 4-cyano-N-(2-((diethylamino)methyl)benzyl)benzoyl (intermediate 3b)

[0045] Following the synthesis method of intermediate 3a, 3-cyanobenzoyl chloride was replaced with 4-cyanobenzoyl chloride to obtain a white solid with a yield of 72.39%. 1 H NMR(300MHz,DMSO-d6)δ9.36(t,J=5.0Hz,1H),8.12–7.87(m,4H),7.39–7.16(m,4 H),4.67(d,J=5.4Hz,2H),3.63(s,2H),2.57–2.35(m,4H),0.96(t,J=7.0Hz,6H).

[0046] (2) Synthesis of (Z)-N-(2-((diethylamino)methyl)benzyl)-4-(N'-hydroxyamino)benzoyl (intermediate 4b)

[0047] Following the synthesis method of intermediate 4a, intermediate 3a was replaced with intermediate 3b to obtain a white solid with a yield of 49.46%. 1 H NMR (300MHz, DMSO-d6) δ9.82(d,J=25.4Hz,2H),7.97(d,J=8.5Hz,2H),7.78(d,J=8.5Hz,2H),7.68– 7.51(m,2H),7.46–7.27(m,2H),5.93(s,2H),4.71–4.28(m,4H),3.12(s,4H),1.28(t,J=6.8Hz,6H).

[0048] (3) Synthesis of N-(2-((diethylamino)methyl)benzyl)-4-(5-(3,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0049] Referring to the synthesis method of Example 1, intermediate 4a was replaced with intermediate 4b to obtain a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-4-(5-(3,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 39.67%. 1 H NMR(400MHz,DMSO-d6)δ9.31(t,J=5.7Hz,1H),8.31–8.24(m,1H),8.23–8.15 (m,3H),8.14–8.07(m,1H),8.06(d,J=1.8Hz,1H),8.04(d,J=1.8Hz,1H),7.35 –7.30(m,2H),7.28–7.21(m,2H),4.66(d,J=5.7Hz,2H),3.06(s,2H),2.56(d, J=0.6Hz,2H),2.50(d,J=2.0Hz,2H),0.98(t,J=7.1Hz,6H).HRMS(ESI):found 477.2107,calcd forC 27 H 26 F2N4O2[M+H] + Example 3 of 477.2097

[0050] (1) Synthesis of 2-cyano-N-(2-((diethylamino)methyl)benzyl)benzoyl (intermediate 3c)

[0051] Following the synthesis method of intermediate 3a, 3-cyanobenzoyl chloride was replaced with 2-cyanobenzoyl chloride to obtain a white solid with a yield of 55.04%. 1 H NMR(300MHz, DMSO-d6)δ10.20(s,1H),8.27(d,J=49.0Hz,1H),7.94–7.69(m,2H),7.36–6.93(m,4H),5.11( s,1H),4.40(d,J=5.5Hz,1H),3.75(s,1H),3.56(s,1H),2.60–2.37(m,4H),1.88(s,1H),1.13–0.89(m,6H).

[0052] (2) Synthesis of (Z)-N-(2-((diethylamino)methyl)benzyl)-4-(N'-hydroxyamino)benzoyl (intermediate 4c)

[0053] Following the synthesis method of intermediate 4a, intermediate 3a was replaced with intermediate 3c to obtain a white solid with a yield of 46.33%.

[0054] (3) Synthesis of N-(2-((diethylamino)methyl)benzyl)-2-(5-(3,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0055] Following the synthesis method of Example 1, intermediate 4a was replaced with intermediate 4b, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-2-(5-(3,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 33.23%. HRMS(ESI): found 477.2103, calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0056] Example 4

[0057] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-phenyl-1,2,4-oxadiazol-3-yl)benzoyl

[0058] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with benzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-phenyl-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 54.72%. 1 H NMR(300MHz,DMSO-d6)δ9.49(t,J=5.1Hz,1H),8.54(s,1H),8.35–8.17(m,3H),8.10(d,J=7.6Hz,1H ),7.86–7.64(m,4H),7.44–7.21(m,4H),4.68(d,J=5.2Hz,2H),3.68(s,2H),0.99(t,J=7.0Hz,6H). 13 C NMR (151MHz, DMSO) δ176.15,168.40,165.53,138.53,137.82,135.99,133.97,130.94,130.82,130.13,130.08,130.05, 128.85,128.44,127.78,127.30,126.82,126.17,123.76,55.75,46.44,41.36,11.44.HRMS(ESI):found441.2285,calcd for C 27 H28 N4O2[M+H] + 441.2297

[0059] Example 5

[0060] Synthesis of 3-(5-(2-chlorophenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl

[0061] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-chlorobenzoic acid, yielding a pale yellow solid, namely 3-(5-(2-chlorophenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl, with a yield of 53.73%. 1 H NMR (400MHz, DMSO-d6) δ9.45(t,J=5.6Hz,1H),8.54(s,1H),8.26(d,J=7.8Hz,1H),8.22–8.17(m,1H),8.10(d,J=7.9Hz,1H),7 .81–7.70(m,3H),7.67–7.61(m,1H),7.36–7.21(m,4H),4.67(d,J=5.6Hz,2H),3.64(d,J=14.0Hz,2H),0.97(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ174.73,168.17,165.54,138.53,137.72,136.04,134.84,132.85,132.67,131.85,130.88,130. 20,130.10,128.77,128.49,127.75,127.25,126.62,126.28,123.12,55.74,46.44,41.29,11.45.HRMS(ESI):found 475.1905,calcdfor C 27 H 27 ClN4O2[M+H] + 475.1895

[0062] Example 6

[0063] Synthesis of 3-(5-(3-chlorophenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl

[0064] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-chlorobenzoic acid, yielding a pale yellow solid, namely 3-(5-(3-chlorophenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl, with a yield of 47.76%. 1 H NMR(300MHz,DMSO-d6)δ9.91(s,1H),8.60(s,1H),8.23(t,J=7.6Hz,2H),8.12(d,J=8.5Hz,2H),7.85–7 .53(m,6H),7.51–7.28(m,2H),4.65(d,J=4.9Hz,2H),4.54(s,2H),3.18(s,4H),1.33(t,J=6.1Hz,6H). 13 C NMR (151MHz, DMSO) δ174.88,168.44,165.61,138.67,135.81,134.69,133.70,132.44,132.09,131.18,130.94,130. 21,130.06,129.11,127.88,127.42,127.09,126.61,126.18,125.62,60.21,46.46,41.30,14.53.HRMS(ESI):found 475.1906,calcd for C 27 H 27 ClN4O2[M+H] + 475.1895

[0065] Example 7

[0066] Synthesis of 3-(5-(4-chlorophenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl

[0067] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-chlorobenzoic acid, yielding a pale yellow solid, namely 3-(5-(4-chlorophenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl, with a yield of 55.22%. 1H NMR (300MHz, DMSO-d6) δ9.47(t,J=5.5Hz,1H),8.53(t,J=1.7Hz,1H),8.29–8.17(m,3H),8.10(d,J=7.7H z,1H),7.80–7.67(m,3H),7.40–7.22(m,4H),4.68(d,J=5.5Hz,2H),3.67(s,2H),0.98(t,J=7.0Hz,6H). 13 C NMR (151MHz, DMSO) δ175.28,168.45,165.50,138.81,138.53,137.80,135.99,130.89,130.84,130.26,130.24, 130.12,130.03,128.80,127.74,127.26,126.67,126.21,122.62,55.76,46.44,41.32,11.46.HRMS(ESI):found 475.1904,calcd for C 27 H 27 ClN4O2[M+H] + 475.1895

[0068] Example 8

[0069] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-fluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0070] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-fluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-fluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 64.68%. 1 H NMR (300MHz, DMSO-d6) δ9.42(s,1H),8.51(s,1H),8.23(d,J=6.9Hz,2H),8.07(d,J=7.5Hz,1H),7.87–7.63(m,2 H),7.63–7.40(m,2H),7.40–7.14(m,4H),4.65(d,J=5.1Hz,2H),3.62(d,J=12.4Hz,2H),0.95(t,J=6.8Hz,6H). 13C NMR(151MHz,DMSO)δ173.06,168.01,165.39,161.20,159.49,138.40,13 7.67,136.19,136.14135.90,131.24,130.78,130.73,130.05,129.95,1 28.68,127.64,127.14,126.53,126.09,125.88,117.76,117.63,112.13,112.06,55.63,46.32,41.21,11.33.HRMS(ESI):found459.2191,calcd for C 27 H 27 FN4O2[M+H] + 459.2191

[0071] Example 9

[0072] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-fluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0073] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-fluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-fluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 55.66%. 1 H NMR(300MHz,DMSO-d6)δ9.44(s,1H),8.52(s,1H),8.24(d,J=7.6Hz,1H),8.15–7.88(m,3H),7.82 –7.52(m,3H),7.29(d,J=20.5Hz,4H),4.66(d,J=5.1Hz,2H),3.66(s,2H),0.97(t,J=6.8Hz,6H). 13 C NMR (151MHz, DMSO) δ174.95,168.36,165.34,163.39,161.76,138.40,137.68,135.88,132.42,132.37,130.78,130.02,129.95,128.70, 127.64,127.15,126.50,126.07,125.63,125.57,124.66,120.91,120.77,115.13,114.97,55.63,46.31,41.22,11.33.HRMS(ESI):found 459.2196,calcd for C27 H 27 FN4O2[M+H] + 459.2191

[0074] Example 10

[0075] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-fluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0076] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-fluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-fluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 54.11%. 1 H NMR (300MHz, DMSO-d6) δ9.45(s,1H),8.52(s,1H),8.24(t,J=8.8Hz,3H),8.09(d,J=7.6Hz,1H),7.70(t,J=7.7Hz,1 H),7.51(t,J=8.5Hz,2H),7.41–7.14(m,4H),4.68(d,J=5.0Hz,2H),3.64(d,J=12.5Hz,2H),0.97(t,J=6.8Hz,6H). 13 CNMR(151MHz,DMSO)δ175.11,168.25,166.19,165.35,164.51,138.41,137.66,135.84,131.20,131.13,130.77,130.65,129 .95,129.83,128.70,127.62,127.12,126.60,126.06,120.34,117.28,117.13,55.64,46.31,41.22,11.31.HRMS(ESI):found 459.2198,calcdfor C 27 H 27 FN4O2[M+H] + 459.2191

[0077] Example 11

[0078] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-nitrophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0079] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-nitrobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-nitrophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 54.02%. 1 H NMR(300MHz,DMSO-d6)δ9.43(s,1H),8.51(s,1H),8.33–8.17(m,3H),8.11(d,J=7.9Hz,1H),8.06–7.98(m ,2H),7.74(t,J=7.8Hz,1H),7.43–7.17(m,4H),4.66(d,J=5.5Hz,2H),3.66(s,2H),0.97(t,J=6.9Hz,6H). 13 C NMR (151MHz, DMSO) δ173.35,168.38,165.46,148.58,143.29,138.48,137.80,136.08,134.79,134.48,132.16,131.06, 130.84,130.18,128.74,127.72,127.24,126.26,126.24,125.50,118.05,55.76,46.44,41.27,11.48.HRMS(ESI):found 486.2134,calcd for C 27 H 27 N5O4[M+H] + 486.2136

[0080] Example 12

[0081] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-nitrophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0082] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-nitrobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-nitrophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 35.04%. 1H NMR (300MHz, DMSO-d6) δ9.51(t,J=5.6Hz,1H),8.88(t,J=1.9Hz,1H),8.69–8.52(m,3H),8.29(d,J=7.8Hz,1H),8.13(d,J=8.1Hz ,1H),7.99(t,J=8.1Hz,1H),7.74(t,J=7.9Hz,1H),7.42–7.17(m,4H),4.67(d,J=5.6Hz,2H),3.67(s,2H),0.99(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ174.49,168.61,165.45,148.75,138.55,137.82,136.04,134.45,132.06,131.08,130.88,130.21, 130.14,128.81,128.18,127.74,127.26,126.47,126.22,125.23,123.02,55.77,46.51,41.29,11.52.HRMS(ESI):found 486.2134,calcd for C 27 H 27 N5O4[M+H] + 486.2136

[0083] Example 13

[0084] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-nitrophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0085] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-nitrobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-nitrophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 40.88%. 1 H NMR (300MHz, DMSO-d6) δ9.45(t,J=5.6Hz,1H),8.55(t,J=1.7Hz,1H),8.53–8.43(m,4H),8.30–8.23(m,1H),8.15–8.06(m,1 H),7.74(t,J=7.8Hz,1H),7.38–7.31(m,2H),7.29–7.20(m,2H),4.67(d,J=5.6Hz,2H),3.67(s,2H),0.98(t,J=7.1Hz,6H). 13C NMR (151MHz, DMSO) δ174.57,168.71,165.49,150.57,138.51,136.05,130.98,130.89,130.18,130.13,130. 02,129.12,128.77,127.75,127.27,126.49,126.28,125.14,55.76,46.46,41.30,11.49.HRMS(ESI):found 508.1955,calcd for C 27 H 27 N5O4[M+Na] + 508.1956

[0086] Example 14

[0087] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-methoxyphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0088] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-methoxybenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-methoxyphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 43.69%. 1 H NMR (400MHz, DMSO-d6) δ9.45(t,J=5.4Hz,1H),8.52(s,1H),8.24(d,J=7.8Hz,1H),8.09(t,J=8.3Hz,2H),7.7 1(t,J=7.8Hz,2H),7.41–7.14(m,7H),4.67(d,J=5.6Hz,2H),3.97(s,3H),3.66(s,2H),0.97(t,J=7.1Hz,7H). 13 C NMR (151MHz, DMSO) δ175.76,167.70,165.56,158.72,138.55,137.81,135.97,135.43,131.74,130.90,130.65,130.11,130 .00,128.80,127.75,127.26,127.00,126.17,121.35,113.48,112.70,56.65,55.76,46.44,41.32,11.45.HRMS(ESI):found 471.2393,calcd forC 28 H 30 N4O3[M+H]+ 471.2391

[0089] Example 15

[0090] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-methoxyphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0091] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-methoxybenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-methoxyphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 48.21%. 1 H NMR (300MHz, DMSO-d6) δ9.46(t,J=5.3Hz,1H),8.52(s,1H),8.24(d,J=7.8Hz,1H),8.09(d,J=7.8Hz,1H),7. 85–7.49(m,4H),7.46–7.14(m,5H),4.67(d,J=5.5Hz,2H),3.89(s,3H),3.66(s,2H),0.97(t,J=7.0Hz,6H). 13 C NMR (151MHz, DMSO) δ175.99,168.41,165.49,160.23,138.55,137.79,135.98,131.38,130.91,130.81,130.14,130.01,128 .84,127.76,127.26,126.78,126.18,124.90,120.73,120.05,113.00,56.03,55.77,46.47,41.34,11.46.HRMS(ESI):found 471.2396,calcd forC 28 H 30 N4O3[M+H] + 471.2391

[0092] Example 16

[0093] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-methoxyphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0094] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-methoxybenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-methoxyphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 43.69%. 1 H NMR(300MHz,DMSO-d6)δ9.50(t,J=5.5Hz,1H),8.53(s,1H),8.30–8.07(m,4H),7.73(t,J=7.8Hz ,1H),7.40–7.17(m,6H),4.69(d,J=5.7Hz,2H),3.91(s,3H),3.69(s,2H),1.00(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ175.99,168.24,165.54,163.72,138.56,137.81,135.94,130.90,130.71,130.46,130.09,129 .98,128.83,127.75,127.26,126.97,126.16,116.09,115.54,56.17,55.75,46.44,41.31,11.46.HRMS(ESI):found 471.2401,calcd for C 28 H 30 N4O3[M+H] + 471.2391

[0095] Example 17

[0096] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-methylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0097] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-methylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-methylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 43.67%. 1H NMR (600MHz, DMSO-d6) δ9.49(t,J=5.5Hz,1H),8.59(s,1H),8.30(d,J=7.6Hz,1H),8.23–8.11(m,2H),7.77(t,J=7.8Hz,1H),7.66(t,J=7. 6Hz,1H),7.62–7.48(m,2H),7.42–7.34(m,2H),7.33–7.25(m,2H),4.72(d,J=5.6Hz,2H),3.71(s,2H),2.78(s,3H),1.02(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ176.68,168.00,165.60,139.08,138.55,137.75,135.99,133.28,132.49,130.82,130.68,130.42,130.15 ,130.00,128.71,127.69,127.20,127.13,126.94,126.23,123.05,55.77,46.43,41.23,40.90,21.78,11.49.HRMS(ESI):found 455.2452,calcd for C 28 H 30 N4O2[M+H] + 455.2442

[0098] Example 18

[0099] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-methylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0100] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-methylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-methylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 40.55%. 1H NMR (600MHz, DMSO-d6) δ9.49(t,J=5.5Hz,1H),8.59(s,1H),8.30(d,J=7.6Hz,1H),8.23–8.11(m,2H),7.77(t,J=7.8Hz,1H),7.66(t,J=7. 6Hz,1H),7.62–7.48(m,2H),7.42–7.34(m,2H),7.33–7.25(m,2H),4.72(d,J=5.6Hz,2H),3.71(s,2H),2.78(s,3H),1.02(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ176.19,168.34,165.47,139.65,138.53,137.79,135.95,134.58,130.91,130.77,130.08,130.00,129.95 ,128.85,128.68,127.75,127.27,126.82,126.14,125.56,123.66,55.75,46.44,41.35,40.92,21.23,11.44.HRMS(ESI):found 455.2449,calcd for C 28 H 30 N4O2[M+H] + 455.2442

[0101] Example 19

[0102] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-methylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0103] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-methylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-methylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 48.35%. 1H NMR (600MHz, DMSO-d6) δ9.47(s,1H),8.57(s,1H),8.29(d,J=7.6Hz,1H),8.14(t,J=7.0Hz,3H),7.76(t,J=7.8Hz,1H),7.53(d,J=7.9 Hz,2H),7.40(t,J=7.7Hz,2H),7.35–7.28(m,2H),4.71(t,J=8.2Hz,2H),3.71(d,J=20.3Hz,2H),2.49(s,3H),1.04(t,J=6.9Hz,6H). 13 C NMR (151MHz, DMSO) δ176.18,168.29,165.53,144.44,138.55,135.92,130.95,130.75,130.61,130.10,130.01,129.58 ,128.87,128.37,127.82,127.29,126.87,126.14,121.03,55.70,46.43,41.34,40.92,21.73,11.39.HRMS(ESI):found 455.2450,calcd for C 28 H 30 N4O2[M+H] + 455.2442

[0104] Example 20

[0105] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-ethylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0106] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-ethylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-ethylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 48.41%. 1H NMR (300MHz, DMSO-d6) δ9.42(t,J=5.6Hz,1H),8.53(t,J=1.5Hz,1H),8.29–8.20(m,1H),8.13–8.04(m,2H),7.78–7.59(m,2H),7.58– 7.42(m,2H),7.39–7.19(m,4H),4.67(d,J=5.6Hz,2H),3.65(s,2H),3.20–3.03(m,2H),1.23(t,J=7.5Hz,3H),0.96(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ176.60,168.11,165.63,145.12,138.52,137.78,136.04,133.49,131.05,130.87,130.70,130.67,130.15 ,130.04,128.74,127.73,127.25,127.16,126.94,126.23,122.47,55.78,46.42,41.29,27.29,15.99,11.46.HRMS(ESI):found 469.2603,calcd for C 29 H 32 N4O2[M+H] + 469.2598

[0107] Example 21

[0108] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-ethylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0109] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-ethylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-ethylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 42.36%. 1H NMR (300MHz, DMSO-d6) δ9.48(t,J=5.5Hz,1H),8.51(s,1H),8.21(d,J=7.9Hz,1H),8.14–7.99(m,3H),7.69(t,J=7.8Hz,1H),7.46(d, J=8.3Hz,2H),7.41–7.15(m,4H),4.66(d,J=5.4Hz,2H),3.70(s,2H),2.78–2.62(m,2H),1.20(t,J=7.6Hz,3H),0.97(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ176.14,168.29,165.54,150.36,138.61,135.88,131.02,130.73,130.09,129.94,129.38,128.97,128 .45,127.90,127.31,126.89,126.16,121.25,55.62,46.43,41.35,28.70,15.43,11.26.HRMS(ESI):found469.2599,calcd for C 29 H 32 N4O2[M+H] + 469.2598

[0110] Example 22

[0111] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-propylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0112] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-propylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-propylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 38.19%. 1H NMR (400MHz, DMSO-d6) δ9.46(t,J=5.7Hz,1H),8.53(d,J=1.8Hz,1H),8.25(d,J= 7.8Hz,1H),8.16(d,J=8.0Hz,2H),8.09(d,J=7.8Hz,1H),7.71(t,J=7.8Hz,1H), 7.61(d,J=8.0Hz,2H),7.38–7.30(m,2H),7.29–7.20(m,2H),4.67(d,J=5.5Hz,2 H),3.66(s,2H),1.72–1.56(m,2H),0.97(t,J=7.0Hz,6H),0.86(t,J=7.3Hz,3H). 13 C NMR (151MHz, DMSO) δ176.17,168.34,165.52,152.56,138.55,135.97,130.92,130.77,130.10,130.01,128.83,128.20 ,127.75,127.43,127.27,126.89,126.18,122.03,73.48,55.75,46.43,41.34,32.29,11.43,10.34.HRMS(ESI):found 483.2758,calcd forC 30 H 34 N4O2[M+H] + 483.2755

[0113] Example 23

[0114] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-isopropylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0115] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-isopropylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-isopropylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 45.53%. 1H NMR (300MHz, DMSO-d6) δ9.43(t,J=5.3Hz,1H),8.53(s,1H),8.24(d,J=7.8Hz,1H),8.08(d,J=8.0Hz,1H),8.01–7.92(m,1H),7.78–7.62(m,3H ),7.50–7.40(m,1H),7.39–7.20(m,4H),4.66(d,J=5.6Hz,2H),3.86–3.74(m,1H),3.67(s,2H),1.28(d,J=6.8Hz,6H),0.97(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ176.85,168.11,165.67,149.41,138.52,136.01,133.48,130.91,130.68,130.19,130.07,128 .77,127.78,127.27,126.95,126.91,126.26,122.37,55.73,46.43,41.28,29.90,24.03,11.41.HRMS(ESI):found 483.2756,calcd for C 30 H 34 N4O2[M+H] + 483.2755

[0116] Example 24

[0117] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-isopropylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0118] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-isopropylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-isopropylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 41.13%. 1 H NMR (300MHz, DMSO-d6) δ9.46(t,J=5.6Hz,1H),8.53(s,1H),8.26(d,J=7.8Hz,1H),8.17–7.85(m,3H),7.85–7.49(m,3H) ,7.44–7.14(m,4H),4.67(d,J=5.6Hz,2H),3.67(s,2H),3.13–3.01(m,1H),1.29(d,J=6.9Hz,6H),0.98(t,J=7.1Hz,6H).13 C NMR (151MHz, DMSO) δ176.30,168.38,165.51,150.44,138.54,137.82,135.99,132.13,130.93,130.81,130.18,130.15,130.04,128.86 ,127.77,127.28,126.85,126.16,126.15,126.07,123.79,55.77,46.49,41.34,33.76,24.10,11.49.HRMS(ESI):found483.2766,calcd for C 30 H 34 N4O2[M+H] + 483.2755

[0119] Example 25

[0120] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-isopropylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0121] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-isopropylbenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(4-isopropylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 45.53%. 1 H NMR (300MHz, DMSO-d6) δ9.47(s,1H),8.53(s,1H),8.25(d,J=7.8Hz,1H),8.19–8.05(m,3H),7.72(t,J=7.8Hz,1H),7.56(d,J=8. 3Hz,1H),7.42–7.20(m,4H),4.67(d,J=5.5Hz,2H),3.69(s,2H),3.16–2.88(m,1H),1.26(d,J=6.9Hz,6H),1.00(t,J=6.6Hz,6H). 13C NMR (151MHz, DMSO) δ176.17,168.33,154.93,138.59,130.97,130.78,130.15,130.04,129.92,128.88,128.59,128.08 ,127.32,126.96,126.90,126.19,121.43,46.46,41.31,34.07,24.01,23.90,11.40.HRMS(ESI):found483.2760,calcd for C 30 H 34 N4O2[M+H] + 483.2755

[0122] Example 26

[0123] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(1,2,4-oxadiazol-3-yl)benzoyl

[0124] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with formic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 33.01%. 1 H NMR (300MHz, DMSO-d6) δ9.28(s,1H),8.28(s,1H),8.17(d,J=7.8Hz,1H),8.03(d,J=7.7Hz,1H),7.72(t ,J=7.8Hz,1H),7.43–7.12(m,4H),4.66(d,J=5.3Hz,2H),3.62(d,J=9.7Hz,2H),0.97(t,J=7.0Hz,6H). 13 C NMR (151MHz, DMSO) δ164.57,147.24,138.06,137.61,135.85,135.00,132.31,131.13,130.77,130.56, 130.17,128.98,128.36,127.47,127.05,118.62,111.89,55.69,46.31,40.97,11.49.HRMS(ESI):found 365.1975,calcdfor C 21 H 24 N4O2[M+H] + 365.1972

[0125] Example 27

[0126] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-methyl-1,2,4-oxadiazol-3-yl)benzoyl

[0127] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with acetic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-methyl-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 33.71%. 1 H NMR(300MHz, DMSO-d6)δ9.75(s,1H),8.51(t,J=1.7Hz,1H),8.23–8.14(m,1H),8.13–8.04(m,1H),7.71(t,J=7.8Hz,1H),7 .49(d,J=7.9Hz,3H),7.39(t,J=7.3Hz,1H),4.58(d,J=5.8Hz,2H),3.17(d,J=4.8Hz,2H),2.69(s,2H),1.39–1.17(m,6H).

[0128] Example 28

[0129] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-ethyl-1,2,4-oxadiazol-3-yl)benzoyl

[0130] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with propionic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-ethyl-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 37.92%. 1 H NMR (300MHz, DMSO-d6) δ9.48(s,1H),8.47(s,1H),8.18(d,J=7.7Hz,1H),8.06(t,J=9.1Hz,1H),7.79–7.64(m,1H ),7.47–7.19(m,4H),4.65(d,J=5.6Hz,2H),3.69(s,2H),3.12–2.98(m,2H),1.37(t,J=7.5Hz,3H),1.02(s,6H). 13C NMR (151MHz, DMSO) δ181.98,167.59,132.46,131.29,130.94,130.61,130.32,129.99,128.88,127.78 ,127.33,127.04,126.05,118.73,112.03,55.71,46.48,41.23,20.07,11.42,10.88.HRMS(ESI):found 393.2295,calcd for C 23 H 28 N4O2[M+H] + 393.2285

[0131] Example 29

[0132] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-propyl-1,2,4-oxadiazol-3-yl)benzoyl

[0133] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with n-butyric acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-propyl-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 40.10%. 13 C NMR (151MHz, DMSO) δ180.99,167.61,165.61,138.65,135.81,131.27,131.05,130.61,130.01,129.96,12 8.97,127.91,127.34,127.00,126.07,55.59,46.45,41.25,28.06,19.97,13.78,11.26.HRMS(ESI):found 407.2446,calcd for C 24 H 30 N4O2[M+H] + 407.2442

[0134] Example 30

[0135] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-isopropyl-1,2,4-oxadiazol-3-yl)benzoyl

[0136] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with isobutyric acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-isopropyl-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 36.62%. 1H NMR (300MHz, DMSO-d6) δ9.45(t,J=5.7Hz,1H),8.42(t,J=1.7Hz,1H),8.20–8.11(m,1H),8.10–8.00(m,1H),7.68(t,J=7.8Hz ,1H),7.38–7.30(m,2H),7.29–7.21(m,2H),4.65(d,J=5.6Hz,2H),3.66(s,2H),1.39(d,J=7.0Hz,6H),0.97(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ184.89,167.55,165.50,138.55,137.81,135.90,130.97,130.63,129.99,128 .91,127.80,127.31,127.00,125.99,55.72,46.44,41.36,27.29,20.29,11.40.HRMS(ESI):found 429.2262,calcd for C 24 H 30 N4O2[M+Na] + 429.2261

[0137] Example 31

[0138] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,3-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0139] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2,3-difluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,3-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 50.58%. 1 H NMR (400MHz, DMSO-d6) δ9.49(t,J=5.7Hz,1H),8.54(d,J=1.8Hz,1H),8.26(d,J=7.7Hz,1H),8.15–8.02(m,2H),7.92–7.82(m,1H),7.7 4(t,J=7.8Hz,1H),7.57–7.48(m,1H),7.37–7.31(m,2H),7.30–7.20(m,2H),4.67(d,J=5.6Hz,2H),3.66(s,2H),0.97(t,J=7.1Hz,6H). 13C NMR (151MHz, DMSO) δ172.24,168.26,165.50,138.54,137.80,136.05,130.96,130.87,130.19,130.12,128.77,127.74,127.25,126.58, 126.55,126.53,126.50,126.46,126.38,126.36,126.26,123.00,122.89,114.30,114.25,55.76,46.45,41.28,11.48.HRMS(ESI):found 477.2100,calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0140] Example 32

[0141] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0142] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2,4-difluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,4-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 53.56%. 1 H NMR(300MHz,DMSO-d6)δ9.74(s,1H),8.79(s,1H),8.64–8.46(m,2H),8.36(d,J=7.6Hz,1H),8. 08–7.82(m,2H),7.79–7.43(m,5H),4.94(d,J=4.3Hz,2H),3.97(s,2H),1.26(t,J=6.4Hz,6H). 13C NMR (151MHz, DMSO) δ172.46,168.09,166.69,166.61,165.55,165.00,164.92,162.21,162.12,160.48,16 0.39,138.56,135.96,133.28,133.27,133.21,133.20,130.97,130.84,130.17,130.05,129.66,129.21, 128.87,127.86,127.30,126.59,126.22,119.36,118.42,115.33,114.81,113.80,113.78,113.65,113.6 3,109.34,109.31,109.26,109.24,106.64,106.47,106.30,55.67,46.44,41.31,11.34.HRMS(ESI):found 477.2098,calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0143] Example 33

[0144] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,5-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0145] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2,5-difluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,5-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 43.14%. 1 H NMR (300MHz, DMSO-d6) δ9.39(t,J=5.7Hz,1H),8.44(s,1H),8.17(d,J=7.7Hz,1H),8.02(d,J=7.7Hz,1H),7.97–7.91(m,1H ),7.71–7.52(m,3H),7.26(d,J=5.6Hz,2H),7.22–7.16(m,2H),4.60(d,J=5.6Hz,2H),3.61(s,2H),0.91(t,J=7.0Hz,6H). 13C NMR(151MHz,DMSO)δ172.18,168.21,165.48,159.21,157.61,155.95,138.52,135.99,13 5.13,132.42,131.23,130.94,130.72,130.31,130.19,130.09,128.87,127.81,127.30, 127.20,126.45,126.19,123.03,122.97,122.87,122.81,119.99,119.93,119.83,119.7 7,117.28,117.11,113.29,55.71,46.42,41.36,10.87.HRMS(ESI):found477.2095,calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0146] Example 34

[0147] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,6-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0148] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2,6-difluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2,6-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 41.65%. 1 H NMR (300MHz, DMSO-d6) δ9.48(s,1H),8.54(s,1H),8.27(d,J=7.7Hz,1H),8.12(d,J=7.8Hz,1H),7.96–7.80(m,1H),7.7 5(t,J=7.7Hz,1H),7.49(t,J=9.2Hz,2H),7.38–7.20(m,4H),4.68(d,J=5.6Hz,2H),3.69(s,2H),0.99(t,J=7.0Hz,6H). 13C NMR (151MHz, DMSO) δ169.06,168.29,165.51,161.47,159.76,138.55,136.64,136.57,136.04,130.99,130.22,130.14, 128.85,127.74,127.29,126.42,126.26,113.71,113.69,113.57,113.55,55.62,46.43,41.30,11.38.HRMS(ESI):found 477.2101,calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0149] Example 35

[0150] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3,5-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0151] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3,5-difluorobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3,5-difluorophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 38.68%. 1 H NMR (300MHz, DMSO-d6) δ9.47(s,1H),8.54(s,1H),8.26(d,J=7.7Hz,1H),8.12(d,J=7.8Hz,1H),7.93(d,J=5 .8Hz,2H),7.80–7.69(m,2H),7.40–7.20(m,4H),4.68(d,J=5.5Hz,2H),3.68(s,2H),0.99(t,J=7.0Hz,6H). 13C NMR(151MHz,DMSO)δ174.25,168.59,165.44,164.06,162.41,138.52,13 7.80,136.02,130.98,130.90,130.17,130.10,128.80,127.75,127.27, 126.69,126.62,126.54,126.45,126.24,112.12,112.07,111.96,111.9 4,109.66,109.50,109.32,55.74,46.43,41.32,11.45.HRMS(ESI):found 477.2094,calcd for C 27 H 26 F2N4O2[M+H] + 477.2097

[0152] Example 36

[0153] Synthesis of 3-(5-benzyl-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl

[0154] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with phenylacetic acid, yielding a pale yellow solid, namely 3-(5-benzyl-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl, with a yield of 38.99%. 13 C NMR (151MHz, DMSO) δ178.54,170.64,168.26,165.44,164.70,138.46,138.16,137.77,137.72 ,136.08,135.96,135.59,135.12,134.48,132.42,131.23,131.14,131.12,130.84,130.68,13 0.35,130.30,130.20,129.37,128.69,128.47,127.71,127.59,127.24,127.17,126.29,126. 26,118.74,111.99,55.79,55.75,46.45,46.42,41.27,41.09,11.61,11.47.HRMS(ESI):found 455.2444,calcd for C 28 H 30 N4O2[M+H] + 455.2442

[0155] Example 37

[0156] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(1-phenylethyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0157] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-phenylpropionic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(1-phenylethyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 36.31%. 1 H NMR (300MHz, DMSO-d6) δ9.43(t,J=5.6Hz,1H),8.35(s,1H),8.09(d,J=7.7Hz,1H),7.99(d,J=7.8Hz,1H),7.59(t, J=7.7Hz,1H),7.32–7.13(m,9H),4.58(d,J=6.3Hz,3H),3.56(s,2H),1.66(d,J=7.1Hz,3H),0.86(t,J=6.9Hz,6H). 13 C NMR (151MHz, DMSO) δ182.76,167.71,165.48,140.65,138.50,137.74,135.88,131.06,130.72,130.03,129.98,129.34 ,129.04,127.94,127.85,127.74,127.35,126.83,125.97,55.74,46.43,41.50,37.93,20.02,11.28.HRMS(ESI):found 491.2423,calcd for C 29 H 32 N4O2[M+Na] + 491.2418

[0158] Example 38

[0159] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-phenethyl-1,2,4-oxadiazol-3-yl)benzoyl

[0160] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-phenylpropionic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-phenylethyl-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 33.28%. 1H NMR (300MHz, DMSO-d6) δ9.45(t,J=5.7Hz,1H),8.44(t,J=1.8Hz,1H),8.20–8.01(m,2H),7.68(t,J=7.8H z,1H),7.46–7.19(m,9H),4.65(d,J=5.6Hz,2H),3.74(s,2H),3.22–3.11(m,2H),0.99(t,J=7.1Hz,6H). 13 C NMR (151MHz, DMSO) δ180.44,167.59,165.60,140.10,138.62,135.84,131.05,130.66,130.32,130.01,129.88,128 .91,128.76,127.94,127.34,126.91,126.89,126.05,55.56,46.47,41.25,32.11,28.04,10.81.HRMS(ESI):found 469.2600,calcd for C 29 H 32 N4O2[M+H] + 469.2599

[0161] Example 39

[0162] Synthesis of 3-(5-butyl-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl

[0163] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with n-valeric acid, yielding a pale yellow solid, namely 3-(5-butyl-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl, with a yield of 35.40%. 1 H NMR(300MHz, DMSO-d6)δ8.98(s,1H),7.99(d,J=1.8Hz,1H),7.75–7.66(m,1H),7.65–7.56(m,1H),7.22(t,J=7.8Hz,1H),6.95 –6.75(m,4H),4.20(d,J=5.5Hz,2H),3.21(s,2H),2.18–1.99(m,6H),1.40–1.27(m,2H),1.04–0.87(m,2H),0.61–0.40(m,9H). 13CNMR(151MHz,DMSO)δ180.51,166.58,165.54,145.36,138.58,137.78,135.97,130.94,130.61,129.97,128.8 7,127.77,127.30,127.00,126.04,55.71,46.46,41.28,28.47,25.94,21.99,13.89,11.40.HRMS(ESI):found 443.2416,calcd for C 25 H 32 N4O2[M+Na] + 443.2418

[0164] Example 40

[0165] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-phenylpropyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0166] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 4-phenylbutyric acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-phenylpropyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 39.35%. 1 H NMR (300MHz, DMSO-d6) δ9.42(t,J=5.7Hz,1H),8.45(s,1H),8.10(dd,J=24.5,7.9Hz,2H),7.70–7.59(m,1H),7.30–7.14(m,9H ),4.65(d,J=5.5Hz,2H),3.63(s,2H),2.98(t,J=7.5Hz,2H),2.69(t,J=7.5Hz,2H),2.14–2.03(m,2H),0.93(t,J=7.0Hz,6H). 13C NMR (151MHz, DMSO) δ180.77,167.63,165.49,141.37,138.58,137.68,135.9 1,135.08,132.43,131.27,130.91,130.69,130.60,130.25,129.95,129.89 ,128.88,128.80,128.53,127.75,127.60,127.23,127.15,127.00,126.43, 126.06,55.73,46.44,41.33,34.69,28.14,25.37,11.37.HRMS(ESI):found 483.2759, calcd forC 30 H 34 N4O2[M+H] + 483.2755

[0167] Example 41

[0168] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(5-phenylpentyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0169] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with benzohexanoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(5-phenylpentyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 47.20%. 1 H NMR (300MHz, DMSO-d6) δ9.45(t,J=5.7Hz,1H),8.48(s,1H),8.20–8.04(m,2H),7.67(t,J=7.6Hz,1H),7.45–7.10(m,9H),4.68(d, J=5.5Hz,2H),3.65(s,2H),2.99(t,J=7.4Hz,2H),1.87–1.77(m,2H),1.66–1.56(m,2H),1.43–1.35(m,2H),0.96(t,J=7.0Hz,6H). 13C NMR (151MHz, DMSO) δ180.77,167.63,165.49,141.37,138.58,137.68,135.9 1,135.08,132.43,131.27,130.91,130.69,130.60,130.25,129.95,129.89 ,128.88,128.80,128.53,127.75,127.60,127.23,127.15,127.00,126.43, 126.06,55.73,46.44,41.33,34.69,28.14,25.37,11.37.HRMS(ESI):found 511.3070, calcd forC 32 H 38 N4O2[M+H] + 511.3068

[0170] Example 42

[0171] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-(trifluoromethoxy)phenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0172] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 2-trifluoromethoxybenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(2-(trifluoromethoxy)phenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 48.66%. 1 HNMR (300MHz, DMSO-d6) δ8.74(s,1H),7.86(s,1H),7.63(d,J=7.7Hz,1H),7.54(d,J=7.7Hz,1H),7.41(d,J=7.8Hz,1H ),7.28–7.10(m,1H),7.10–6.89(m,3H),6.74–6.43(m,4H),3.98(d,J=5.2Hz,2H),2.96(s,2H),0.26(t,J=7.0Hz,6H). 13C NMR (151MHz, DMSO)173.39,168.19,165.54,146.48,138.55,137.71,136.07,135.78,132.18,130.86,130.83,130.08,130.04,1 29.13,128.74,127.70,127.20,126.53,126.32,123.44,121.34,119.63,117.98,55.76,46.41,41.25,11.41.HRMS(ESI):found 525.2109,calcd for C 28 H 27 F3N4O3[M+H] + 525.2108

[0173] Example 43

[0174] Synthesis of 3-(5-(3-cyclopropylphenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl

[0175] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-cyclopropylbenzoic acid, yielding a pale yellow solid, namely 3-(5-(3-cyclopropylphenyl)-1,2,4-oxadiazol-3-yl)-N-(2-((diethylamino)methyl)benzyl)benzoyl, with a yield of 48.67%. 1 H NMR(300MHz,DMSO-d6)δ9.48(t,J=5.7Hz,1H),8.52(t,J=1.8Hz,1H),8.26–8.18(m,1H) ,8.14–8.06(m,1H),7.96–7.89(m,1H),7.86(d,J=1.8Hz,1H),7.69(t,J=7.8Hz,1H),7. 50(t,J=7.7Hz,1H),7.42–7.29(m,3H),7.28–7.19(m,2H),4.67(d,J=5.5Hz,2H),3.65( s,2H),2.12–2.01(m,1H),1.06–1.00(m,2H),0.96(t,J=7.1Hz,6H),0.81–0.73(m,2H). 13C NMR (151MHz, DMSO)176.17,168.35,165.47,145.91,138.60,135.93,130.92,130.77,130.65,130.09,129.96,129.92,128 .90,127.77,127.25,126.83,126.18,125.36,125.31,123.71,55.74,46.47,41.33,15.36,11.40,10.18.HRMS(ESI):found 481.2599,calcd for C 30 H 32 N4O2[M+H] + 481.2598

[0176] Example 44

[0177] Synthesis of N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-morpholinylphenyl)-1,2,4-oxadiazol-3-yl)benzoyl

[0178] Referring to the synthesis method of Example 1, the 3,4-difluorobenzoic acid in step 5 of Example 1 was replaced with 3-morpholinobenzoic acid, yielding a pale yellow solid, namely N-(2-((diethylamino)methyl)benzyl)-3-(5-(3-morpholinophenyl)-1,2,4-oxadiazol-3-yl)benzoyl, with a yield of 45.85%. 1 H NMR(300MHz,DMSO-d6)δ9.45(t,J=5.6Hz,1H),8.52(t,J=1.7Hz,1H),8.28–8 .22(m,1H),8.13–8.04(m,1H),7.72(t,J=7.8Hz,1H),7.68–7.57(m,2H),7.5 2(t,J=7.9Hz,1H),7.37–7.31(m,3H),7.29–7.21(m,2H),4.67(d,J=5.6Hz,2 H),3.83–3.74(m,4H),3.66(s,2H),3.29–3.20(m,4H),0.98(t,J=7.1Hz,6H). 13C NMR (151MHz, DMSO) δ176.56,168.35,165.55,152.07,138.55,135.97,130.92,130.78,130.75,130.16,130.02,128.82,127 .77,127.27,126.87,126.20,124.45,120.37,118.79,113.72,66.45,55.77,48.39,46.48,41.32,11.48.HRMS(ESI):found 526.2809,calcd forC 31 H 35 N5O3[M+H] + 526.2813

[0179] Table 1. Structural formulas of compounds in Examples 1-44

[0180]

[0181]

[0182]

[0183]

[0184]

[0185]

[0186]

[0187]

[0188] The following are the pharmacodynamic tests and results of some compounds in this invention:

[0189] 1. Assay for butyrylcholinesterase inhibitory activity:

[0190] Drugs and reagents: Analytical compounds, AChE (EC3.1.1.7, selected from electric eel), eqBChE (EC3.1.1.8, selected from horse serum). 5,5'-Dithiobis(2-nitrobenzoic acid) (DTNB), acetylthiocholine (ATC) iodide, and butyrylthiocholine (BTC) iodide were purchased from Sigma-Aldrich; tacrine hydrochloride (9-Amin-1,2,3,4-tetrahydroacridine hydrochloride hydrate) was purchased from BioTrend.

[0191] Instrument: THERMO Varioskan Flash full-wavelength multi-functional microplate reader.

[0192] Experimental methods:

[0193] (1) Prepare buffer solution: Dissolve 13.6g potassium dihydrogen phosphate in 1L of water, and adjust the pH to 8.0±0.1 with potassium hydroxide. Store the solution at 4℃ for later use.

[0194] (2) Preparation of 0.01M DTNB solution: Dissolve 0.396g DTNB and 0.15g sodium bicarbonate in 100mL of water to prepare 0.01M DTNB solution, store at -30℃ for later use.

[0195] (3) Preparation of 0.075M ATC and BTC solution: Dissolve 0.217g ATC in 10mL of water to prepare 0.075M ATC and BTC solution, store at -30℃ for later use; Dissolve 0.237g BTC in 10mL of water to prepare 0.075M BTC solution, store at -30℃ for later use.

[0196] (4) Preparation of AChE and BChE solutions: Dissolve 5000 units of AChE in 1 mL of 1% gel solution, then dilute with water to 100 mL to obtain an AChE solution with a concentration of 5 units / mL. Store at -30℃ for later use. Dissolve 5000 units of BChE in 1 mL of 1% gel solution, then dilute with water to 100 mL to obtain a BChE solution with a concentration of 5 units / mL. Store at -30℃ for later use.

[0197] (5) Preparation of test solution: Dissolve the test compound in DMSO to prepare a solution with a concentration of 10. -3 A solution of M was then diluted with methanol to obtain solutions with concentrations of 10. -4 10 -5 10 -6 10 -7 10 -8 10 -9 10 -10 A solution of M.

[0198] Before the experiment, all solutions were warmed to room temperature, and the AChE and BChE solutions were diluted with water by half to prepare an enzyme solution with a concentration of 2.5 units / mL. Background UV absorbance was measured using a blank buffer (3 mL). 100 μL of the test compound solution, 100 μL of DTNB solution, and 100 μL of enzyme solution were added to 3 mL of buffer. After adding 20 μL of BTC solution to trigger the reaction, timing was immediately started, and the test solution was rapidly mixed. UV absorbance was measured at 412 nM after 2 min. The blank control group was measured using an equal volume of methanol instead of the test compound solution. All tests were performed in triplicate. Using the UV absorbance of the blank control group as 100%, the absorbance values ​​of the test compound at various concentrations were recorded. The results were used to calculate the corresponding IC50 using GraphPad Prism™ software (GraphPad Software, San Diego, CA, USA) in a non-linear regression analysis model. 50 The values ​​are shown in Table 2.

[0199] All 44 compounds in Table 2 exhibited high selective inhibitory activity against BChE, with some drugs showing an IC50 threshold. 50 Reaching the 10 nanomolar level.

[0200] Table 2 Results of cholinesterase activity assay for compounds

[0201]

[0202]

[0203]

[0204]

[0205] The inhibitory activity of each compound against the enzyme is indicated by "+", and "++" represents IC50. 50 The range is from 1 μM to 1 mM, and "+++" indicates IC. 50 The range is from 1 nM to 1 μM, and "++++" represents IC. 50 <1nM. b AChE (EC 3.1.1.7) from electric eel. cBuChE (EC 3.1.1.8) from horse serum.

[0206] S11-1014 is the parent molecule of butyrylcholinesterase inhibitor, with the following structure:

[0207]

[0208] 2. L02 cytotoxicity assay:

[0209] Drugs and reagents: The test compound and DMEM medium (01-050-1A) were purchased from Biological Industries, FBS fetal bovine serum (04-001-1A) were purchased from Biological Industries, and MTT thiazolyl blue reagent (KGT525500) was purchased from Kaiji Biotechnology.

[0210] Instrument: THERMO Varioskan Flash full-wavelength multi-functional microplate reader.

[0211] Experimental methods:

[0212] (1) Cell seeding: The cells were seeded at a density of 5000 cells / well in a 96-well plate and cultured at 37°C in a 5% CO2 incubator for 24 hours.

[0213] (2) Discard the culture medium, wash once with PBS buffered salt solution, add 100 μL of different concentrations of the compound prepared with DMEM culture medium to each well, and add only DMEM culture medium without the compound to the blank control group. Incubate the 96-well plate at 37°C and 5% CO2 for 24 h.

[0214] (3) Add 15 μL of MTT solution (5 mg / mL, i.e. 0.5% MTT) to each well in the dark and continue culturing for 2-3 h.

[0215] (4) Discard the culture medium, add 100 μL of dimethyl sulfoxide to each well, and gently shake to fully dissolve the crystals in the dimethyl sulfoxide. Measure the absorbance (OD) of each well at 490 nm using a multi-functional microplate reader. The OD value of the normal group was set as 100%. The cell viability was calculated using the following formula: Cell viability = (OD value of the drug-treated group - OD value of the blank group) / (OD value of the normal group - OD value of the blank group) × 100%. The experimental results are as follows: Figure 1 As shown. Cytotoxicity assessment of L02 hepatocytes confirmed that all compounds had excellent safety profiles, with activity exceeding 50% at a concentration of 100 μM.

[0216] 3. Nrf2 activation activity assay:

[0217] Experimental methods:

[0218] (1) In vitro cell culture. 293T cells transfected with the ARE luciferase reporter gene plasmid were cultured at 37°C and 5% CO2.

[0219] (2) 293T-ARE cells in the logarithmic growth phase were treated with 0.25% trypsin digestion solution to prepare a solution with a concentration of 4×10⁻⁶. 5Cell suspension. Add 100 μL to each well of a 96-well microplate and incubate overnight.

[0220] (3) Prepare the test compound at twice the test concentration using culture medium, and add 100 μL to the corresponding wells. tert-butylhydroquinone (tBHQ) and dimethyl fumarate (DMF) are used as positive controls, and DMSO is used as a negative control. Incubate the 96-well microplate with the added compounds at 37°C and 5% CO2 for 12 h.

[0221] (4) Prepare the 5× lysis buffer in the luciferase detection kit as a 1× lysis buffer for later use.

[0222] (5) Remove the 96-well plate, aspirate the culture medium from the wells, wash the cells with 1×PBS buffer, and aspirate the PBS buffer after washing. Add 25 or 30 μL of 1× cell lysis buffer to each well and lyse on ice for 15 min. After lysis, let stand for 3-5 min, and aspirate 20 μL of supernatant to the corresponding 96-well white microplate.

[0223] (6) Place the white ELISA plate into the Thermo Scientific Luminoskan Asent chemiluminescence microplate reader. Before testing, add 100 μL of luciferase assay reagent to each well (prepared by uniformly mixing one vial of luciferase assay substrate and one vial of luciferase assay buffer from the luciferase assay kit). Take the reading within 1 minute after adding the reagent. The results are as follows: Figure 2 As shown.

[0224] The results showed that compounds 30, 32, and 33 all exhibited good Nrf2 activation activity, superior to the positive control agents tert-butylhydroquinone (TBHQ) and dimethyl fumarate (DMF). Among them, compound 33 showed the highest Nrf2 induction fold at a dosage concentration of 20 μM. Considering both the BChE inhibitory activity and the toxicity of the compounds, compound 33 was selected for pharmacodynamic evaluation.

[0225] 4. Lipid peroxide assay

[0226] Experimental reagent: Aβ 1–42 The following reagents were purchased from Biological Industries: (Darmstadt, Germany), Lipid Peroxidation Detection Kit (Shanghai Beyotime Biotechnology Co., Ltd.), analyte, DMEM medium (01-050-1A), FBS fetal bovine serum (04-001-1A), and MTT thiazolyl blue reagent (KGT525500).

[0227] Experimental consumables and instruments: 6-well plates, fluorescence inverted microscope

[0228] Experimental steps:

[0229] SH-SY5Y cells in the logarithmic growth phase were selected and cultured at a concentration of 2.5 × 10⁻⁶. 5 Cells were seeded at a density of 6-well plates and incubated at 37°C, 5% CO2 for 24 h. The culture medium was discarded, the cells were washed once with PBS, and pretreated with test compound 33 (10 μM) for 24 h. Subsequently, β-amyloid protein (Aβ) was added to the cell system. 1-42 Oligomer (5 μM) was added and incubated for another 24 hours. The culture medium was removed, and 1 mL of BODIPY 581 / 591C11 staining working solution was added to each well. The cells were incubated at 37°C for 30 min. After incubation, the supernatant was aspirated, and the cells were washed three times with PBS. 1 mL of PBS was added to each well, and the cells were visualized and evaluated using a fluorescence microscope. The results are shown below. Figure 3 As shown.

[0230] Compared with the model group, SH-SY5Y cells pretreated with 10 μM compound 33 showed increased levels of reduced lipid biomarkers and reduced Aβ-induced cellular lipid peroxidation.

[0231] 5. Morris water maze test for mice

[0232] All animal experiments were approved by the Animal Ethics Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences and the New Drug Evaluation Research Center of China Pharmaceutical University (Nanjing, China), and were strictly conducted in accordance with the U.S. National Institutes of Health's "Guidelines for the Care and Use of Laboratory Animals".

[0233] The recombinant human β-amyloid protein (Aβ) used in the experiment was pretreated with 1,1,1,3,3,3-hexafluoroisopropanol (HFIP). 1–42 The peptide was purchased from Merck Millipore (Darmstadt, Germany). Oligomeric Aβ 1–42 The preparation method followed previous literature and was used as a modeling stimulant. Mice were anesthetized with isoflurane, and oligomeric Aβ was injected bilaterally into the hippocampus via stereotactic surgery. 1–42 An AD model was established. The experimental animals were divided into 8 groups (n=5 in each group): (1) Blank control group: intraperitoneal injection of solvent (ip); (2) Sham operation group: intravenous injection of saline (icv); (3) Model group: intravenous injection of oligomerized Aβ. 1–42 (10 μg / animal, icv); (4) Positive control group: intraventricular injection of oligomerized Aβ 1–42(10 μg / animal, icv) combined with intraperitoneal injection of the positive control drug rivastigmine (1 mg / kg, ip); (5) Nrf2 activator compound 6 single drug group: intraventricular injection of oligomerized Aβ 1–42 (10 μg / animal, icv) combined with intraperitoneal injection of test compound 6 (1 mg / kg, ip); (6) BChE inhibitor S11-1014 monotherapy group: intraventricular injection of oligomerized Aβ 1–42 (10 μg / animal, icv) combined with intraperitoneal injection of test compound S11-1014 (1 mg / kg, ip); (7) Compound 6 + S11-1014 combination group: intraventricular injection of oligomerized Aβ 1–42 (10 μg / animal, icv) combined with intraperitoneal injection of test compound 6 (1 mg / kg, ip) and S11-1014 (1 mg / kg, ip); (8) Compound 33 group: intraventricular injection of oligomerized Aβ 1–42 Compound 33 of the present invention was administered (10 μg / animal, icv) in combination with intraperitoneal injection (1 mg / kg, ip).

[0234] Spatial learning and reference memory abilities were assessed using the Morris Water Maze (MWM) test. The experiment included 5 days of orientation and navigation training (a concealed platform was fixed in a quadrant of a pool with a diameter of 120 cm and a water depth of 40 cm, at a water temperature of 25℃). On the 6th day, the platform was removed, and a 60-second exploration test was conducted, recording the percentage of time spent in the target quadrant and the number of times the original platform area was traversed. Behavioral processes were recorded using the Panlab SMART 3.0 video tracking system, and data analysis was performed using GraphPad Prism 5 software. The results are as follows: Figure 4 As shown. Injection of Aβ 1-42 The mice exhibited significant cognitive impairment in all tests: in the water maze (days 8–13), they displayed chaotic swimming patterns. Figure 4 A) and a long escape latency period ( Figure 4 B) Both showed impaired spatial learning ability in mice. S11-1014 and 6 monotherapy almost completely improved these deficiencies, demonstrating the therapeutic potential of BChE inhibition and Nrf2 activation against Aβ-induced neurotoxicity. Notably, the combination therapy group showed superior cognitive improvement compared to either monotherapy, with the dual-target molecule 33 exhibiting the most significant effect, superior to both monotherapy and equivalent dose (1 mg / kg) combinations. It also offers additional advantages such as lower molecular weight, simplified dosage, and avoidance of potential drug interaction toxicities, collectively highlighting the therapeutic efficacy of the dual-target molecule against AD enhancement.

[0235] S11-1014 is the parent molecule of the BChE inhibitor mentioned above, and compound 6 is the parent molecule of the Nrf2 activator, with the following structure:

[0236]

Claims

1. A compound of a benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof, characterized by, The compound structure is shown as general formula I: wherein, R1represents ortho, meta, para phenyl; R2represents hydrogen, C 1～6 alkyl, alkyl chain length C 1～6 phenylalkyl, substituted or unsubstituted phenyl; the substitution is selected from the group consisting of halogen, nitro, -O-C 1～4 alkyl, C 1～6 alkyl, halogen substituted -O-C 1～4 alkyl, cyclopropyl, morpholinyl.

2. The compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof according to claim 1, characterized in that, R1represents R2represents hydrogen, C 1～6 alkyl, an alkyl chain length of C 1-5 phenylalkyl, substituted or unsubstituted phenyl; the substitution being selected from the group consisting of halogen, nitro, methoxy, C 1～4 alkyl, trifluoromethoxy, cyclopropyl, morpholinyl.

3. The compound of the benzamide-oxadiazole skeleton according to claim 1, or a pharmaceutically acceptable salt thereof, characterized in that, is any one of the following compounds or a pharmaceutically acceptable salt thereof:

4. The compound according to claim 1, or a pharmaceutically acceptable salt thereof, wherein The pharmaceutically acceptable salt is a salt of the compound with any one of the following acids: hydrochloric acid, hydrogen bromide, sulfuric acid, carbonic acid, oxalic acid, citric acid, malic acid, succinic acid, tartaric acid, phosphoric acid, lactic acid, pyruvic acid, acetic acid, maleic acid, methanesulfonic acid, citric acid, benzenesulfonic acid, p-toluenesulfonic acid or ferulic acid.

5. A method of preparing a compound of the benzamide-oxadiazole skeleton according to any one of claims 1 to 4, or a pharmaceutically acceptable salt thereof, characterized by, The preparation method of the compound shown as general formula I comprises the following steps:

6. A method of preparing a compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof according to claim 5, characterized by, Step a is specifically reacting the starting material with potassium carbonate and diethylamine in acetonitrile at 40-70 °C to give the intermediate Step b is specifically reacting the intermediate with sodium borohydride in methanol at 0-5 °C to give the intermediate 7. A method of preparing the compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof according to claim 5, characterized by, Step c is specifically stirring intermediate with o-, m- and p-substituted cyanobenzoyl chloride and cesium carbonate in N,N'-dimethylformamide at 40-60°C to give intermediate R1is as defined in claim 1.

8. A method of preparing the compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof according to claim 5, characterized by, Step d is specifically with hydroxylamine hydrochloride, potassium carbonate in anhydrous ethanol at 70-90 °C to reflux to obtain the intermediate Step e is specifically amide condensation with R2-COOH to obtain the target compound; The above R1 and R2 are defined in claim 1.

9. A pharmaceutical composition, characterized by, The compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof according to any one of claims 1-4 and a pharmaceutically acceptable carrier.

10. Use of the compound of the benzamide-oxadiazole skeleton or a pharmaceutically acceptable salt thereof according to any one of claims 1-4 in the preparation of a drug for preventing or treating Alzheimer's disease.

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