A 2-hydroxy-6-alkoxyquinoline compound and its applications

Abstract

This invention belongs to the field of biomedical technology, specifically relating to a 2-hydroxy-6-alkoxyquinoline compound and its applications. The structure of the compound is shown in formula (I) or formula (II). The 2-hydroxy-6-alkoxyquinoline compound provided by this invention has a significant inhibitory effect on phosphodiesterase type 3 (PDE3). Furthermore, the 2-hydroxy-6-alkoxyquinoline compound provided by this invention has good water solubility, hepatotoxicity, and bioavailability, and can be used to prepare drugs for treating PDE3-related diseases, providing a range of options for drugs treating PDE3-related diseases.

Description

Technical Field

[0001] This invention belongs to the field of medicinal chemistry technology, and more specifically, relates to a 2-hydroxy-6-alkoxyquinoline compound and its applications. Background Technology

[0002] Cyclic adenosine monophosphate (cAMP) or cyclic guanosine monophosphate (cGMP) are vital second messengers within cells, playing a crucial role in regulating numerous intracellular biological activities, including cell growth and differentiation, secretion of related mediators, smooth muscle contraction and relaxation, and the metabolism of intracellular substances such as lipids and carbohydrates. Phosphodiesterases (PDEs) are the only intracellular pathway for the degradation of cyclic nucleotides, hydrolyzing cAMP and cGMP into inactive AMP and GMP, thus playing a key role in their concentration levels. PDE inhibitors regulate a range of biological functions by inhibiting their degradation. The PDE family comprises 11 families (PDE1–11), exhibiting varying degrees of cAMP specificity, cGMP specificity, or both. They are specifically distributed across different tissues and cells, displaying varying substrate affinities and inhibitor sensitivities. PDE4, PDE7, and PDE8 specifically hydrolyze cAMP; PDE5, PDE6, and PDE9 specifically hydrolyze cGMP; while PDE1, PDE2, PDE3, PDE10, and PDE11 hydrolyze both cAMP and cGMP. Each family participates in different signal transduction pathways and regulates different physiological processes, such as bronchodilation, penile erection, thrombosis, myocardial contraction, T cell activation, and platelet aggregation. In recent years, PDEs have attracted widespread attention from scholars as novel therapeutic targets. Currently, more than six highly effective PDE inhibitors have been successfully marketed, making research on these inhibitors a cutting-edge hot topic in the biomedical field.

[0003] PDE3 is composed of PDE3A and PDE3B genes located on chromosomes 12 and 11, respectively. The most significant difference between PDE3 and other PDEs lies in the presence of a 44-amino acid insert in its catalytic region, which influences PDE3's tertiary structure, catalytic activity, and inhibitory selectivity. PDE3 can hydrolyze both cAMP and cGMP, but its hydrolytic ability for cAMP is approximately ten times that for cGMP. PDE3A is mainly expressed in cardiac tissue, platelets, and vascular smooth muscle cells, while PDE3B is mainly expressed in hepatocytes and adipose tissue (it can increase lipolysis in adipocytes, which has important implications for the treatment of obesity).

[0004] Ciproamide is a selective and potent PDE3 inhibitor with antithrombotic and anti-endothelial proliferation properties. It can regulate cell proliferation, myocardial contractility, platelet aggregation, vascular smooth muscle tone, and bronchodilation. However, the drug has poor metabolic stability and water solubility. Therefore, it is necessary to optimize the drug to develop a PDE3 inhibitor with high activity, good selectivity, and good drug-like properties. Summary of the Invention

[0005] The purpose of this invention is to optimize the structure of ciloxamide drugs and provide a 2-hydroxy-6-alkoxyquinoline compound as a new PDE3 inhibitor to overcome the technical problems of poor metabolic stability and water solubility of current ciloxamide drugs.

[0006] A first aspect of the present invention is to provide a 2-hydroxy-6-alkoxyquinoline compound and its derivatives, said 2-hydroxy-6-alkoxyquinoline compound having the structure of formula (I) or formula (II):

[0007]

[0008] Wherein: R1 and R2 are each independently selected from hydrogen and C. 1～6 Substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups;

[0009] m is selected from 0 to 2; n is selected from 0 to 4; X is selected from -CH2-, -CH2CH2- or -CH=CH-; Y is selected from -CH2- or -C(O)-; Z is selected from -CH- or -N-.

[0010] In another preferred embodiment, R1 and R2 are each independently selected from methyl, ethyl, propyl, isopropyl, butyl, cyclohexyl, pyran-4-yl, phenyl, 2-fluorophenyl, 3-fluorophenyl, 4-fluorophenyl, 3,4-difluorophenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 3-iodophenyl, 4-methylphenyl, 4-methoxyphenyl, pyridin-2-yl, pyridin-3-yl, and pyridin-4-yl.

[0011] In another preferred embodiment, m is selected from 0 or 1; n is selected from 0, 1 or 2.

[0012] In another preferred embodiment, the 2-hydroxy-6-alkoxyquinoline compound may also be a pharmaceutically acceptable salt, solvate, or isomer thereof.

[0013] A second aspect of the invention is to provide the use of formula (I) or formula (II) as described in the first aspect of the invention for preparing inhibitors, medicaments, or pharmaceutical compositions for the prevention, treatment, or adjunctive treatment of diseases related to PDE3 activity or expression levels; preferably, the diseases are immune and inflammatory diseases related to PDE3 activity or expression levels.

[0014] In another preferred embodiment, the diseases associated with PDE3 activity or expression include heart failure, myocardial infarction, arrhythmia, improvement of cardiac function, and bronchodilator.

[0015] The present invention has the following beneficial effects:

[0016] The 2-hydroxy-6-alkoxyquinoline compounds provided by this invention have a significant inhibitory effect on PDE3, and exhibit good water solubility, liver microsomal stability, and bioavailability. They can be used in the preparation of drugs for the treatment and / or prevention of PDE3-related diseases, and have good development potential, providing a range of options for the treatment of PDE3-related diseases. Attached Figure Description

[0017] Figure 1 This is a standard curve diagram for the water solubility test of compound P28 of the present invention;

[0018] Figure 2 This is a standard curve for the water solubility test of ciloxamide.

[0019] Figure 3 This is a blood concentration curve of compound P28 after oral administration;

[0020] Figure 4 This is a graph showing the blood concentration of compound P28 after intravenous administration. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field. Unless otherwise specified, the reagents and materials used in the following embodiments are commercially available.

[0022] Example 1: Synthesis of compounds P1-P20

[0023] 1. Synthesis of intermediate M1

[0024]

[0025] 2,6-Dihydroxyquinoline (3.0 g, 0.019 mol) was dissolved in 70 mL of isopropanol, and DBU (8.6 mL, 0.057 mol) was added. Then, ethyl 4-bromobutyrate (3.2 mL, 0.022 mol) was added dropwise to the system. The mixture was refluxed at 85 °C for 5 h, and the reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M1 (3.7 g, 72.6%).

[0026] 2. Synthesis of intermediate M2

[0027]

[0028] M1 (800 mg, 2.91 mmol) was added to THF / MeOH / H2O (3:2:1) (75 mL), and LiOH solid (365 mg, 8.73 mmol) was slowly added. The mixture was stirred at room temperature for 4–6 h, and the reaction was monitored by TLC. After the reaction was complete, the organic solvent was evaporated to dryness, and the pH was adjusted to 2–4 with hydrochloric acid. The resulting solution was filtered and washed with water to obtain M2 (white solid, 515 mg, 71.68%). 1 H NMR (400MHz, DMSO-d6) δ11.63(s,1H),7.82(d,J=9.6Hz,1H),7.23(d,J=8.8Hz,1H),7.19(s,1H),7.13( d,J=9.0Hz,1H),6.48(d,J=9.5Hz,1H),3.99(t,J=6.7Hz,2H),2.39(t,J=7.4Hz,2H),2.00–1.90(m,2H).

[0029] 3. Synthesis of target compound P1

[0030]

[0031] Intermediate M2 (100 mg, 0.40 mmol) was dissolved in 3.0 mL of DMF, and 0.2 mL of DIPEA (1.2 mmol) was added. Then, 231 mg of HATU (0.6 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylaniline (66 μL, 0.6 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product P1 (white solid, 85 mg, 50.0%). 1H NMR (400MHz, DMSO-d6) δ11.62(s,1H),7.79(d,J=9.5Hz,1H),7.42(s,2H),7.37–7.26(m,3H),7.20(d,J=9.1Hz,1H),7.12 (s,1H),7.05(s,1H),6.47(d,J=9.6Hz,1H),3.89(s,2H),3.15(s,3H),2.17(s,2H),1.90(s,2H),1.27(d,J=14.3Hz,1H). 13 C NMR(101MHz,DMSO-d6)δ171.08,161.55,153.25,143.90,139.80(2C),133.28,129.66,127.57,127.36 ,122.25(2C),119.80,119.68,116.34,110.11,67.13,36.87,29.82,24.60.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 20 H 20 N2O3,337.1547; found,337.1554.

[0032] 4. Synthesis of target compound P2

[0033]

[0034] Following the synthesis method of P1, N-methylaniline was replaced with N-ethylcyclohexylamine to obtain P2 (yellow solid, 103 mg, 71.5%). 1 H NMR(400MHz,Chloroform-d)δ12.56(s,1H),7.74(d,J=9.5Hz,1H),7.38(d,J=9.0Hz,1H),7.19–7. 10(m,1H),6.99(d,J=3.0Hz,1H),6.71(d,J=9.4Hz,1H),4.34(m,1H),4.07(d,J=6.3Hz,2H),3.62–3 .51(m,1H),3.33–3.19(m,2H),2.59–2.47(m,2H),2.22–2.12(m,2H),1.82(d,J=13.4Hz,2H),1.67( d,J=11.3Hz,2H),1.54–1.44(m,1H),1.35(d,J=11.0Hz,2H),1.33–1.21(m,2H),1.19–1.10(m,3H). 13C NMR(101MHz,Chloroform-d)δ171.91,171.36,164.27,154.68,140.68,133.21,121.82,120.75,117.57, 109.73,67.83,57.23,53.81,37.98,36.66,31.14,29.85,26.06,16.87,15.26.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 21 H 28 N2O3, 357.2173 found, 357.2177.

[0035] 5. Synthesis of target compound P3

[0036]

[0037] Following the synthetic method of P1, N-methylaniline was replaced with N-methyltetrahydro-2H-pyran-4-amine to obtain P3 (white solid, 78 mg, 71.9%). 1 H NMR (400MHz, DMSO-d6) δ11.62(s,1H),7.82(d,J=9.5Hz,1H),7.23(d,J=8.9Hz,1H),7.19(s, 1H),7.14(d,J=8.6Hz,1H),6.48(d,J=9.4Hz,1H),4.51(dd,J=14.5,9.4Hz,1H),4.00(t,J=6 .6Hz,2H),3.91–3.84(m,2H),2.75(d,J=45.5Hz,3H),2.55(d,J=7.1Hz,1H),2.45(t,J=7.2H z,1H),2.00–1.89(m,2H),1.79–1.60(m,2H),1.50(d,J=12.6Hz,1H),1.37(d,J=9.6Hz,1H). 13 C NMR(101MHz,DMSO-d6)δ171.20,161.56,153.38,139.83,133.30,122.28,119.89,119.72,110 .11,67.37,66.59,52.65,49.21,30.31,29.37,28.71,26.80,24.42.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 19 H 24 N2O4,345.1809; found,345.1817.

[0038] 6. Synthesis of target compound P4

[0039]

[0040] Following the synthesis method of P1, N-methylaniline was replaced with 4-fluoro-N-methylaniline to obtain P4 (white solid, 90 mg, 52.0%). 1 H NMR (400MHz, DMSO-d6) δ11.61(s,1H),7.79(d,J=9.5Hz,1H),7.36(dd,J=8.6,5.0Hz,2H),7.23(dd,J=21.3,8.7Hz,3H),7.12(d,J=2.6 Hz,1H),7.04(d,J=8.6Hz,1H),6.47(d,J=9.5Hz,1H),3.89(t,J=6.5Hz,2H),3.13(s,3H),2.14(t,J=7.0Hz,2H),1.89(t,J=7.0Hz,2H). 13 C NMR (101MHz, DMSO-d6) δ171.24, 161.63 (2C), 153.29, 140.24, 139.88, 133.30, 129.67 (d, J = 28Hz), 122.28 (2C),119.86,119.74,116.59,116.42(2C),110.13,67.13,36.93,29.83,24.60.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 20 H 19 FN2O3,355.1452; found,355.1457.

[0041] 7. Synthesis of target compound P5

[0042]

[0043] Following the synthesis method of P1, N-methylaniline was replaced with 3-fluoro-N-methylaniline to obtain P5 (white solid, 95 mg, 53.0%). 1H NMR (400MHz, DMSO-d6) δ11.61(s,1H),7.79(d,J=9.6Hz,1H),7.46(q,J=7.7Hz,1H),7.31–7.25(m,1H),7.23–7.15(m,3H),7.13(d,J=2. 8Hz,1H),7.05(dd,J=8.9,2.7Hz,1H),6.47(d,J=9.5Hz,1H),3.92(t,J=6.4Hz,2H),3.17(s,3H),2.44–2.07(m,2H),1.99–1.85(m,2H). 13 C NMR (101MHz, DMSO-d6) δ171.04, 163.47, 161.50, 161.03, 153.22, 145.44 (d, J = 36Hz), 139.75, 133.29, 131. 03,123.64,122.27,119.77,119.65,116.31,110.08,67.07,36.79,29.81,24.53.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 19 FN2O3,355.1452; found,355.1459.

[0044] 8. Synthesis of target compound P6

[0045]

[0046] Following the synthesis method of P1, N-methylaniline was replaced with 2-fluoro-N-methylaniline to obtain P6 (white solid, 90 mg, 52.0%). 1 H NMR (400MHz, DMSO-d6) δ11.61(s,1H),7.79(d,J=9.6Hz,1H),7.56–7.40(m,2H),7.37(t,1H),7.28(t,J=7.8Hz,1H),7.20(d,J=8.9Hz,1H),7.11 (d,J=2.8Hz,1H),7.03(dd,J=8.9,2.8Hz,1H),6.47(d,J=9.5Hz,1H),3.89(t,J=6.4Hz,2H),3.11(s,3H),2.29–2.02(m,2H),1.99–1.77(m,2H). 13C NMR(101MHz,DMSO-d6)δ171.37,161.50,153.19,139.75,133.28,130.93,130.80,130.14,125.57(d,J=12Hz)1 22.25,119.75,119.64,116.85,116.65,116.30,110.10,66.94,36.00,29.23,24.42.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 19 FN2O3,355.1452; found,355.1454.

[0047] 9. Synthesis of target compound P7

[0048]

[0049] Following the synthesis method of P1, N-methylaniline was replaced with 3,4-difluoro-N-methylaniline to obtain P7 (white solid, 105 mg, 57.6%). 1 H NMR (400MHz, DMSO-d6) δ11.62(s,1H),7.80(d,J=9.5Hz,1H),7.48(m,J=19.1,9.5Hz,2H),7.21(d,J=8.8Hz,2H) ,7.13(s,1H),7.05(d,J=9.1Hz,1H),6.47(d,J=9.5Hz,1H),3.91(s,2H),3.14(s,3H),2.20(s,2H),1.91(t,2H). 13 C NMR (101MHz, DMSO-d6) δ171.29,161.71,153.34,140.66 (d, J=16Hz),139.92,133.33,124.86,122.28,119.88 ,119.79,118.11,117.25(d,J=28Hz),116.47,110.14,67.12,36.88,29.87,24.59.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 18 F2N2O3,373.1358; found,373.1365.

[0050] 10. Synthesis of target compound P8

[0051]

[0052] Following the synthesis method of P1, N-methylaniline was replaced with 4-chloro-N-methylaniline to obtain P8 (white solid, 98 mg, 54.1%). 1 H NMR (400MHz, DMSO-d6) δ11.68(s,1H),7.80(d,J=9.6Hz,1H),7.47(d,J=8.2Hz,2H),7.35(d,J=8.5Hz,2H),7.26(d,J=8.9 Hz,1H),7.13(s,1H),7.05(d,J=8.4Hz,1H),6.46(d,J=9.6Hz,1H),3.90(s,2H),3.15(s,3H),2.22(s,2H),,1.90(t,2H). 13 C NMR(101MHz,DMSO-d6)δ171.07,161.53(2C),153.22,142.76,139.79,133.30,129.60,129.32,12 2.27(2C),119.78,119.68,116.39,110.09,67.07,36.80,29.83,24.55.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 19 ClN2O3,371.1157; found,371.1163.

[0053] 11. Synthesis of target compound P9

[0054]

[0055] Following the synthesis method of P1, N-methylaniline was replaced with 3-chloro-N-methylaniline to obtain P9 (white solid, 91 mg, 50.3%). 1 H NMR (400MHz, DMSO-d6) δ11.62(s,1H),7.80(d,J=9.6Hz,1H),7.43(dd,J=15.6,7.9Hz,3H),7.29(d,J=7.5Hz,1H),7.21(d,J=8.9Hz,1H), 7.13(d,J=2.7Hz,1H),7.06(d,J=8.9Hz,1H),6.47(d,J=9.5Hz,1H),3.92(t,J=6.5Hz,2H),3.17(s,3H),2.23(s,2H),1.98–1.87(m,2H). 13C NMR(101MHz,DMSO-d6)δ171.47,161.97,153.68,145.76,140.22,133.98,133.76,131.50,127.91,12 6.73,122.74,120.23,120.13,116.79,110.55,67.52,37.30,30.27,24.98.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 19 ClN2O3,371.1157; found,371.1164.

[0056] 12. Synthesis of target compound P10

[0057]

[0058] Following the synthesis method of P1, N-methylaniline was replaced with 2-chloro-N-methylaniline to obtain P10 (white solid, 90 mg, 50%). 1 H NMR (400MHz, DMSO-d6) δ11.60(s,1H),7.79(d,J=9.5Hz,1H),7.62(t,1H),7.51(t,1H),7.43(t,2H),7.20(d,J=9.0Hz,1H),7.11(d,J=2 .7Hz,1H),7.03(dd,J=8.9,2.7Hz,1H),6.47(d,J=9.5Hz,1H),3.89(t,J=6.3Hz,2H),3.08(s,3H),2.17–1.98(m,2H),1.96–1.84(m,2H). 13 C NMR(101MHz,DMSO-d6)δ171.02,161.48,153.17,140.55,139.73,133.27,131.80,130.44,130.38,130.04 ,128.90,122.24,119.74,119.62,116.27,110.10,66.95,35.33,29.45,24.32.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 19 ClN2O3,371.1157; found,371.1165.

[0059] 13. Synthesis of target compound P11

[0060]

[0061] Following the synthesis method of P1, N-methylaniline was replaced with 4-methyl-N-methylaniline to obtain P11 (white solid, 102 mg, 59.6%). 1 H NMR (400MHz, DMSO-d6) δ11.62(s,1H),7.79(d,J=9.5Hz,1H),7.21(t,3H),7.16(d,J=7.9Hz,2H),7.13(s,1H),7.04(d,J=9.0 Hz,1H),6.47(d,J=9.5Hz,1H),3.88(t,J=6.4Hz,2H),3.12(s,3H),2.30(s,3H),2.14(t,J=7.5Hz,2H),1.89(t,J=6.9Hz,2H). 13 C NMR(101MHz,DMSO-d6)δ170.90,161.30,153.01,141.09,139.55,136.74,133.06,129.92(2C),126.90(2C ),122.05,119.57,119.44,116.09,109.87,66.90,36.61,29.56,24.40,20.37.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 21 H 22 N2O3, 351.1703; found, 351.1710.14, Synthesis of target compound P12

[0062]

[0063] Following the synthesis method of P1, N-methylaniline was replaced with N-isopropylcyclohexylamine to obtain P12 (yellow solid, 83 mg, 45.8%). 1H NMR (400MHz, DMSO-d6) δ11.63(s,1H),7.82(d,J=9.6Hz,1H),7.23(d,J=8.9Hz,1H),7.18(d, J=3.0Hz,1H),7.13(dd,J=8.9,2.7Hz,1H),6.48(d,J=9.5Hz,1H),3.99(t,J=6.7Hz,2H),3.44 (d,J=17.0Hz,2H),2.46–2.36(m,2H),1.97–1.86(m,2H),1.69(d,J=12.2Hz,2H),1.61–1.42 (m,3H),1.36(d,J=11.4Hz,1H),1.32–1.15(m,6H),1.10(d,J=6.7Hz,3H),1.06–0.93(m,1H). 13 C NMR(101MHz,DMSO-d6)δ170.34,161.61,153.42,139.87,133.31,122.27,119.91,119.76,116.42,110.16,67 .35,53.55,47.75,45.74,30.68,30.49,29.79,25.45,25.24,24.83,20.66,20.61.HRMS(ESI-TOF)m / z:[M+H] + calcdfor C 22 H 30 N2O3,371.2329; found,371.2335.

[0064] 15. Synthesis of target compound P13

[0065]

[0066] Following the synthesis method of P1, N-methylaniline was replaced with N-isopropylaniline to obtain P13 (white solid, 97 mg, 51.8%). 1 H NMR (400MHz, DMSO-d6) δ11.61(s,1H),7.79(d,J=9.6Hz,1H),7.49–7.36(m,3H),7.24–7.14(m,3H),7.11(d,J=2.8Hz,1H),7.03(dd,J=8.9,2.8 Hz,1H),6.47(dd,J=9.5,4.7Hz,1H),4.91–4.79(m,1H),3.86(t,J=6.3Hz,2H),1.98(t,2H),1.87(m,J=7.4,6.8Hz,2H),0.95(d,J=6.8Hz,6H).13 C NMR(101MHz,DMSO-d6)δ170.34,161.54,153.24,139.80,138.32,133.26,130.40(2C),129.26,128.21,122.25 ,119.78,119.68,116.33,110.15,110.07,67.12,66.93,45.11,30.86,24.57,20.80.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 24 N2O3,365.1860; found,365.1865.

[0067] 16. Synthesis of target compound P14

[0068]

[0069] Following the synthesis method of P1, N-methylaniline was replaced with N-ethylaniline to obtain P14 (purple solid, 110 mg, 64.0%). 1 H NMR (400MHz, DMSO-d6) δ11.61(s,1H),7.79(d,J=9.6Hz,1H),7.44(t,J=7.5Hz,2H ),7.36(t,J=7.3Hz,1H),7.25(d,J=7.0Hz,2H),7.20(d,J=8.9Hz,1H),7.11(s,1H ),7.04(d,J=9.1Hz,1H),6.47(d,J=9.6Hz,1H),3.88(t,J=6.3Hz,2H),3.64(q,J= 7.1Hz,2H),2.11(t,J=7.3Hz,2H),1.89(m,J=6.7Hz,2H),0.98(t,J=7.1Hz,3H).. 13 C NMR(101MHz,DMSO-d6)δ170.44,161.50,153.22,142.04,139.75,133.27,129.62(2C),128.41,127.73,12 2.25(2C),119.76,119.65,116.30,110.07,67.10,43.20,30.16,24.58,12.90.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 21 H 22N2O3, 351.1703; found, 351.1712.17, Synthesis of target compound P15

[0070]

[0071] Following the synthesis method of P1, N-methylaniline was replaced with N-butylaniline to obtain P15 (white solid, 116 mg, 62.7%). 1 H NMR (400MHz, DMSO-d6) δ11.61(s,1H),7.80(d,J=9.6Hz,1H),7.44(t,J=7.6Hz,2H),7. 36(t,J=7.5Hz,1H),7.22(dd,J=16.3,8.2Hz,3H),7.12(d,1H),7.03(d,J=9.3Hz,1H),6 .47(d,J=9.5Hz,1H),3.88(t,J=6.3Hz,2H),3.61(t,J=7.3Hz,2H),2.11(t,J=7.2Hz,2 H),1.89(t,J=6.8Hz,2H),1.40–1.29(m,2H),1.25–1.20(m,2H),0.81(t,J=7.2Hz,3H). 13 C NMR(101MHz,DMSO-d6)δ170.70,161.53,153.24,142.28,139.79,133.27,129.65,128.33(2C),127.70,122.26,1 19.78(2C),119.67,116.32,110.08,67.09,47.92,30.13,29.41,24.62,19.43,13.70.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 23 H 26 N2O3,379.2016; found,379.2025.

[0072] 18. Synthesis of target compound P16

[0073]

[0074] Following the synthesis method of P1, N-methylaniline was replaced with N-propylaniline to obtain P16 (purple solid, 105 mg, 58.9%). 1H NMR (400MHz, DMSO-d6) δ11.60(s,1H),7.79(d,J=9.6Hz,1H),7.44(t,J=7.5Hz,2H),7.3 5(t,J=7.3Hz,1H),7.25(d,J=7.0Hz,2H),7.20(d,J=8.9Hz,1H),7.12(d,J=2.8Hz,1H), 7.03(dd,J=9.0,2.7Hz,1H),6.47(d,J=9.5Hz,1H),3.88(t,J=6.4Hz,2H),3.58(t,2H), 2.12(t,J=7.2Hz,2H),1.89(m,J=6.8Hz,2H),1.43–1.32(m,2H),0.80(t,J=7.4Hz,3H). 13 C NMR(101MHz,DMSO-d6)δ170.72,161.46,153.19,142.28,139.71,133.26,129.58,128.27(2C),127.64,122.2 3,119.72(2C),119.62,116.27,110.08,67.08,49.85,30.10,24.59,20.50,11.05.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 22 H 24 N2O3,365.1860; found,365.1866.

[0075] 19. Synthesis of target compound P17

[0076]

[0077] Following the synthesis method of P1, N-methylaniline was replaced with 3-iodo-N-methylaniline to obtain P17 (white solid, 120 mg, 53.1%). 1 H NMR (400MHz, DMSO-d6) δ11.60(s,1H),7.80(d,J=9.5Hz,1H),7.72(t,J=9.5Hz,2H),7.34(d,J=8.0Hz,1H),7.22(dd,J=8.4,5.0Hz,2H), 7.14(d,J=2.7Hz,1H),7.07(d,J=8.5Hz,1H),6.47(d,J=9.5Hz,1H),3.92(t,J=6.6Hz,2H),3.15(s,3H),2.20(s,2H),1.96–1.84(m,2H). 13C NMR(101MHz,DMSO-d6)δ171.66,161.47,153.20,145.20,139.73(2C),135.78,133.28,131.31,127.00, 122.25,119.75,119.64,116.30,110.11,94.95,67.06,36.86,29.76,24.49.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 19 IN2O3,463.0513; found,463.0522.

[0078] 20. Synthesis of target compound P18

[0079]

[0080] Following the synthesis method of P1, N-methylaniline was replaced with 4-methoxy-N-methylaniline to obtain P18 (white solid, 96 mg, 50.3%). 1 H NMR (400MHz, DMSO-d6) δ11.60(s,1H),7.79(d,J=9.5Hz,1H),7.21(d,J=8.6Hz,3H),7.12(d,J=2.7Hz,1H),7.04(dd,J=8.9,2.8Hz,1H),6. 95(d,J=8.7Hz,2H),6.47(d,J=9.5Hz,1H),3.88(t,J=6.4Hz,2H),3.76(s,3H),3.11(s,3H),2.14(t,J=7.2Hz,2H),1.89(m,J=6.7Hz,2H). 13 C NMR(101MHz,DMSO-d6)δ171.28,161.48,158.26,153.21,139.71,136.56,133.26,128.48(2C),122.24,11 9.74,119.63,116.27,114.73(2C),110.09,67.12,55.28,36.91,29.71,24.59.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 21 H 22 N2O4,367.1652; found,367.1662;.

[0081] 21. Synthesis of target compound P19

[0082]

[0083] Following the synthesis method of P1, N-methylaniline was replaced with N-ethylpyridine-3-amine to obtain P19 (yellow solid, 93 mg, 54.1%). 1 H NMR (400MHz, DMSO-d6) δ11.61 (s, 1H), 8.54 (d, J = 16.1Hz, 2H), 7.78 (t, J = 9. 6Hz,2H),7.49(dd,J=8.0,4.8Hz,1H),7.20(d,J=8.9Hz,1H),7.13(s,1H),7. 04(d,J=9.0Hz,1H),6.47(d,J=9.5Hz,1H),3.89(t,J=6.4Hz,2H),3.67(q,J= 7.2Hz,2H),2.11(t,J=7.1Hz,2H),1.97–1.85(m,2H),0.99(t,J=7.1Hz,3H). 13 C NMR(101MHz,DMSO-d6)δ170.55,161.48,153.19,149.49,148.69,139.74,138.51,136.11,133.28,124.4 0,122.26,119.75,119.64,116.30,110.07,67.02,43.31,30.26,24.47,12.83.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 21 N3O3,352.1656; found,352.1661.

[0084] 22. Synthesis of target compound P20

[0085]

[0086] Following the synthetic method of P1, N-methylaniline was replaced with 2-ethylaminopyridine to obtain P20 (white solid, 93 mg, 54.1%). 1H NMR (400MHz, DMSO-d6) δ11.61(s,1H),8.49(d,J=4.5Hz,1H),7.88(td,J=7.7,1.9Hz,1H),7. 80(d,J=9.5Hz,1H),7.42(d,J=8.0Hz,1H),7.33(dd,J=7.4,4.9Hz,1H),7.20(d,J=9.0Hz,1H) ,7.13(d,J=2.7Hz,1H),7.06(dd,J=9.0,2.8Hz,1H),6.47(d,J=9.4Hz,1H),3.92(t,J=6.4Hz ,2H),3.78(q,J=7.1Hz,2H),2.33(t,J=7.3Hz,2H),2.03–1.87(m,2H),1.03(t,J=7.1Hz,3H). 13 C NMR(101MHz,DMSO-d6)δ171.09,161.49,154.69,153.21,149.01,139.75,138.72,133.28,122.37,122.2 5,121.85,119.79,119.64,116.29,110.10,67.08,42.06,30.55,24.61,13.37.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 20 H 21 N3O3,352.1656; found,352.1665.

[0087] Example 2: Synthesis of compounds P21-P26

[0088] 1. Synthesis of intermediate M3

[0089]

[0090] 6-hydroxy-3,4-dihydro-2(1H)quinolinone (3.0 g, 0.019 mol) was dissolved in 70 mL of isopropanol, and DBU (8.6 mL, 0.057 mol) was added. Then, ethyl 4-bromobutyrate (3.2 mL, 0.022 mol) was added dropwise to the system. The mixture was refluxed at 85 °C for 5 h, and the reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M3 (pale yellow solid, 3.4 g, 66.40%).

[0091] 2. Synthesis of intermediate M4

[0092]

[0093] M3 (5.0 g, 1.79 mmol) was added to THF / H2O (40:1, 60 mL), and LiOH solid (128 mg, 5.37 mmol) was slowly added. The mixture was stirred at room temperature for 4–6 h, and the reaction was monitored by TCL. After the reaction was complete, the organic solvent was evaporated to dryness, and the pH was adjusted to 2–4 with hydrochloric acid. The resulting solution was filtered and washed with water to obtain intermediate M4 (white solid, 4.2 g, 94.1%). 1 H NMR (400MHz, DMSO-d6) δ12.09(s,1H),9.88(s,1H),6.75(d,J=9.3Hz,2H),6.70(dd,J=8.5,2.7Hz, 1H),3.90(t,J=6.4Hz,2H),2.81(t,J=7.5Hz,2H),2.37(m,J=13.6,7.4Hz,4H),1.97–1.79(m,2H).

[0094] 3. Synthesis of target compound P21

[0095]

[0096] Intermediate M4 (0.40 mmol) was dissolved in 3.0 mL of DMF, and 0.2 mL of DIPEA (1.2 mmol) was added. Then, HATU (0.231 mg, 0.6 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylcyclohexylamine (86 μL, 0.6 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product, P21 (yellow solid, 48 mg, 34.8%). 1 H NMR(400MHz,Chloroform-d)δ9.76(s,1H),6.73(s,1H),6.62(s,2H),4.37(s,1H),3.90(s,2H),2.82(s,2 H),2.75(s,3H),2.45(d,J=39.8Hz,4H),2.03(s,2H),1.79–1.64(m,2H),1.54(s,3H),1.33–1.12(m,5H). 13CNMR(101MHz,Chloroform-d)δ171.96,171.77,154.79,130.98,124.81,116.45,114.18,113.12,67.51, 56.45,52.27,30.86,30.57,30.26,29.87,29.48,27.14,25.62,25.24,24.85.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 28 N2O3,345.2173; found,345.2178.

[0097] 4. Synthesis of target compound P22

[0098]

[0099] Following the synthetic method for the final product P21, N-methylcyclohexylamine was replaced with N-ethylcyclohexylamine to obtain P22 (pale yellow solid, 57 mg, 40.0%). 1 H NMR (400MHz, DMSO-d6) δ9.89 (s, 1H), 6.75 (d, J = 9.7Hz, 2H), 6.70 (d, J = 8.9Hz, 1H), 3.91 (q, J=6.0Hz,2H),3.57(d,J=11.8Hz,1H),3.20(dd,J=18.5,7.6Hz,2H),2.81(t,J=7.5Hz,2H), 2.46–2.33(m,4H),1.97–1.83(m,2H),1.72(d,J=13.1Hz,2H),1.61(d,J=13.7Hz,2H),1.50 (s,1H),1.45(d,J=12.3Hz,2H),1.23(s,3H),1.08(q,J=7.3Hz,2H),0.99(d,J=6.9Hz,1H). 13 C NMR(101MHz,DMSO-d6)δ170.38,169.72,153.72,131.68,124.82,115.76,114.00,112.92,67.04,56.00, 52.96,37.28,35.59,31.19,30.36,30.30,28.94,25.64,25.39,16.57,15.10.HRMS(ESI-TOF)m / z:[M+H] + calcdfor C 21 H 30N2O3,359.2329; found,359.2332.

[0100] 5. Synthesis of target compound P23

[0101]

[0102] Following the synthetic method for the final product P21, N-methylcyclohexylamine was replaced with 4-chloro-N-methylaniline to obtain P23 (pale yellow solid, 144 mg, 32.1%). 1 H NMR(400MHz,Chloroform-d)δ8.81(s,1H),7.36(d,J=8.1Hz,2H),7.10(d,J=8.2Hz,2H),6.72(d,J=9.2Hz,1H),6.62(s,2H),3 .88(t,J=6.0Hz,2H),3.24(s,3H),2.91(t,J=7.6Hz,2H),2.60(t,J=7.5Hz,2H),2.24(t,J=7.3Hz,2H),2.04(d,J=6.6Hz,2H). 13 C NMR(101MHz,Chloroform-d)δ172.43,171.76,154.94,147.20,142.61,130.80,130.13,12 8.85,125.09,116.40(2C),114.44(2C),113.18,67.23,37.47,31.55,30.68,25.76,25.18.

[0103] HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 21 ClN2O3,373.1313; found,373.1319.

[0104] 6. Synthesis of target compound P24

[0105]

[0106] Following the synthetic method for the final product P21, N-methylcyclohexylamine was replaced with N-methyltetrahydro-2H-pyran-4-amine to obtain P24 (white solid, 21 mg, 15.2%). 1H NMR(400MHz,Chloroform-d)δ9.63(d,J=8.6Hz,1H),6.73(d,J=8.3Hz,1H),6 .62(d,J=9.8Hz,2H),4.75–4.62(m,1H),4.00–3.89(m,4H),3.39(q,J=12.7,1 2.2Hz,2H),2.83(t,J=7.6Hz,4H),2.78(d,J=13.2Hz,3H),2.55–2.41(m,4H) ,2.11–1.99(m,2H),1.89–1.70(m,1H),1.69–1.62(m,1H),1.53–1.41(m,2H). 13 C NMR(101MHz,Chloroform-d)δ172.02,171.78,154.67,130.94,124.78,116.30,114.14,113.02,67 .34,67.19(2C),53.58,49.38,30.49,30.19,29.63,29.35,25.56,24.69.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 19 H 26 N2O4, 347.1965; found, 347.1972.7, Synthesis of target compound P25

[0107]

[0108] Following the synthetic method for the final product P21, N-methylcyclohexylamine was replaced with N-methylaniline to obtain P25 (white solid, 65 mg, 48.1%). 1 H NMR(400MHz, DMSO-d6)δ9.87(s,1H),7.44(t,J=7.5Hz,2H),7.35(d,J=7.5Hz,1H),7.33–7.27(m,2H),6.73(d,J=8.6Hz,1H),6.68(s,1H),6.6 2(dd,J=8.7,2.7Hz,1H),3.81(t,J=6.5Hz,2H),3.16(s,3H),2.80(dd,J=8.5,6.5Hz,2H),2.42–2.32(m,2H),2.15(s,2H),1.92–1.80(m,2H). 13C NMR(101MHz,DMSO-d6)δ171.05,169.68,153.58,143.89,131.66,129.70,129.59,127.30,124.76,11 5.69(2C),113.96,112.90(2C),66.90,36.82,30.33,29.78,25.06,24.62.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 20 H 22 N2O3,339.1703; found,339.1713.

[0109] 8. Synthesis of target compound P26

[0110]

[0111] Following the synthetic method for the final product P21, N-methylcyclohexylamine was replaced with N-methyl-p-fluoroaniline to obtain P26 (purple solid, 70 mg, yield 49.2%). 1 H NMR (400MHz, DMSO-d6) δ9.88(s,1H),7.40–7.32(m,2H),7.25(t,J=8.5Hz,2H),6.73(d,J=8.5Hz,1H),6.68(s,1H),6.62(d,J=8. 1Hz,1H),3.80(t,J=6.4Hz,2H),3.13(s,3H),2.80(t,2H),2.44–2.33(m,2H),2.12(t,J=7.4Hz,2H),1.85(q,J=7.2,6.7Hz,2H). 13 C NMR(101MHz,DMSO-d6)δ171.63,170.20,154.07,140.70,140.67,132.15,130.06125.2 6,116.97,116.75,116.20,114.42,113.37,67.34,37.31,30.82,30.25,25.55,25.08. 13 C NMR (101MHz, DMSO-d6) δ171.16,169.74,153.60,140.23,140.20,131.68,129.60 (d, J=24Hz),124.80,116.5 1,116.29,115.74(2C),113.96,112.90,66.88,36.85,30.35,29.78,25.09,24.62.HRMS(ESI-TOF)m / z:[M+H]+ calcd for C 20 H 21 FN2O3,357.1609; found,357.1615.

[0112] Example 3 Synthesis of compound P27

[0113] 1. Synthesis of intermediate M5

[0114]

[0115] 6-hydroxy-3,4-dihydro-2(1H)quinolinone (100 mg, 0.6 mmol) was dissolved in 10 mL of isopropanol, and DBU (274 μL, 1.8 mmol) was added. Then, methyl (S)-2-(Boc-amino)-4-bromobutyrate (222 mg, 0.72 mol) was added dropwise to the system. The mixture was refluxed at 85 °C for 5 h, and the reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M5 (white solid, 93 mg, 40.0%). 1 H NMR (400MHz, Methanol-d4) δ6.81–6.76(m,2H),6.73(dd,J=8.7,2.5Hz,1H),5.02(m,J=12.5,6.2Hz,1H),4.29(m,J=10.0,4.5Hz,1H),4.01(p,J=5.9,5 .1Hz,2H),2.90(dd,J=8.5,6.6Hz,2H),2.52(dd,J=8.5,6.6Hz,2H),2.30–2 .20(m,1H),2.12–1.97(m,1H),1.42(d,J=2.1Hz,9H),1.25(d,J=6.6Hz,3H).

[0116] 2. Synthesis of intermediate M6

[0117]

[0118] M5 (93 mg, 0.25 mmol) was added to THF / H2O (40:1, 10 mL), and LiOH solid (23 mg, 1.0 mmol) was slowly added. The mixture was stirred at room temperature for 4–6 h, and the reaction was monitored by TLC. After the reaction was complete, the organic solvent was evaporated to dryness, and the pH was adjusted to 2–4 with hydrochloric acid. The resulting solution was filtered and washed with water to obtain intermediate M6 (white solid, 85 mg, 97.2%). 1¹H NMR (400MHz, DMSO-d⁶) δ 9.89 (s, ¹H), 7.16 (d, J = 8.2 Hz, ¹H), 6.78–6.73 (m, 2H), 6.70 (dd, J = 8.6, 2.7 Hz, 1H), 4.07 (m, J = 9.1, 4.6 Hz, 1H), 3.99–3.90 (m, 2H), 2.81 (t, J = 7.5 Hz, 2H), 2.39 (dd, J = 8.5, 6.5 Hz, 2H), 2.17–2.03 (m, ¹H), 2.01–1.85 (m, 1H), 1.36 (s, 9H). 3. Synthesis of intermediate M7

[0119]

[0120] Intermediate M6 (85 mg, 0.19 mmol) was dissolved in 3.0 mL of DMF, and 0.2 mL of DIPEA (1.2 mmol) was added. Then, 231 mg of HATU (0.6 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylcyclohexylamine (25.1 mg, 0.22 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product M7 (yellow solid, 38 mg, 69.0%).

[0121] 4. Synthesis of target compound P27

[0122]

[0123] Intermediate M7 (38 mg, 0.08 mmol) was dissolved in 3 mL of dichloromethane, and trifluoroacetic acid (59 μL, 0.8 mmol) was added. After stirring at room temperature for 1 h, the solvent was removed by concentration, diluted with water, and the pH was adjusted to 6-8 with sodium bicarbonate. The mixture was then extracted with ethyl acetate, dried over anhydrous sodium sulfate, and separated by column chromatography to obtain a yellow oil product P27 (26 mg, 78%). 1H NMR(400MHz, Methanol-d4)δ6.84–6.71(m,3H),4.39–4.27(m,1H),4.19–4.03(m,2H),4.01–3.90( m,1H),3.78–3.65(m,1H),2.94(s,1H),2.89(m,J=8.2,7.6,2.6Hz,2H),2.82(s,1H),2.51(dd,J=8. 4,6.8Hz,2H),2.11–1.99(m,1H),1.98–1.85(m,1H),1.85–1.74(m,2H),1.74–1.66(m,1H),1.62(d d,J=12.0,3.6Hz,2H),1.58–1.54(m,1H),1.54–1.44(m,1H),1.43–1.33(m,2H),1.18–1.10(m,1H). 13 C NMR(101MHz,Methanol-d4)δ176.19,173.45,156.00,132.50,126.64,117.42,115.26,114.19,65.91, 57.47,54.86,36.49,35.85,31.83,31.43(2C),30.76,29.79,28.25,26.48.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 29 N3O3,360.2282; found,360.2291.

[0124] Example 4 Synthesis of compound P28

[0125] 1. Synthesis of intermediate M8

[0126]

[0127] Compound 2,6-dihydroxyquinoline (100 mg, 0.6 mmol) was dissolved in 10 mL of isopropanol, and DBU (274 μL, 1.8 mmol) was added. Then, methyl (S)-2-(Boc-amino)-4-bromobutyrate (222 mg, 0.72 mmol) was added dropwise to the system. The mixture was refluxed at 85 °C for 5 h, and the reaction was monitored by TCL. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M8 (white solid, 90.0 mg, 39.0%). 1H NMR(400MHz, Methanol-d4)δ7.92(d,J=9.5Hz,1H),7.30(d,J=8.8Hz,1H),7.24–7.17(m,2H),7.00(d,J=8.3Hz,1H),6.61 (d,J=9.5Hz,1H),4.41–4.26(m,1H),4.18–4.08(m,2H),2.37–2.22(m,1H),2.15–2.03(m,1H),1.44(s,3H),1.41(s,9H).

[0128] 2. Synthesis of intermediate M9

[0129]

[0130] M8 (90 mg, 0.24 mmol) was added to THF / H2O (40:1, 10 mL), and LiOH solid (23 mg, 0.96 mmol) was slowly added. The mixture was stirred at room temperature for 4–6 h, and the reaction was monitored by TCL. After the reaction was complete, the organic solvent was evaporated to dryness, and the pH was adjusted to 2–4 with hydrochloric acid. The resulting solution was filtered and washed with water to obtain intermediate M9 (white solid, 85 mg, 97.2%). 1 H NMR (400MHz, DMSO-d6) δ12.57(s,1H),11.62(s,1H),7.83(d,J=9.6Hz,1H),7.23(d,J=8.9Hz,1H),7.19(t,J=3.4Hz,1H),7.17 –7.12(m,1H),6.48(d,J=9.5Hz,1H),4.16–4.07(m,1H),4.06–3.95(m,2H),2.23–2.09(m,1H),2.08–1.90(m,1H),1.36(s,9H).

[0131] 3. Synthesis of intermediate M10

[0132]

[0133] Intermediate M9 (85 mg, 0.19 mmol) was dissolved in 3.0 mL of DMF, and 0.2 mL of DIPEA (1.2 mmol) was added. Then, HATU (231 mg, 0.6 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylcyclohexylamine (25 mg, 0.22 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product, M10 (yellow solid, 37 mg, 69.0%). 1 H NMR (400MHz, Methanol-d4) δ7.92 (dd, J=9.5, 1.9Hz, 1H), 7.31 (dd, J=8.9, 5.4Hz, 1H), 7 .26–7.17(m,2H),6.61(dd,J=9.5,1.6Hz,1H),4.37–4.26(m,1H),4.20–4.02(m,2H),3.8 5(s,1H),3.00–2.79(m,3H),2.16(dd,J=13.4,6.5Hz,1H),2.01(m,J=14.4,9.5,5.1Hz, 1H),1.92–1.75(m,4H),1.69–1.54(m,5H),1.39(d,J=3.8Hz,9H),1.29(d,J=4.6Hz,1H).

[0134] 4. Synthesis of target compound P28

[0135]

[0136] Intermediate M10 (37 mg, 0.08 mmol) was dissolved in 3 mL of dichloromethane, and trifluoroacetic acid (59 μL, 0.8 mmol) was added. After stirring at room temperature for 1 h, the solvent was removed by concentration, diluted with water, and the pH was adjusted to 6-8 with sodium bicarbonate. The mixture was then extracted with ethyl acetate, dried over anhydrous sodium sulfate, and separated by column chromatography to obtain the yellow oil product P28 (25 mg, 78%). 1H NMR(400MHz, Methanol-d4)δ7.91(dd,J=9.5,2.8Hz,1H),7.30(dd,J=9.0,7.1Hz,1H),7.24–7.16( m,2H),6.61(dd,J=9.5,2.3Hz,1H),4.40–4.28(m,1H),4.27–4.17(m,1H),4.16–4.03(m,2H),3.79– 3.67(m,1H),2.89(d,J=47.8Hz,3H),2.19–2.05(m,1H),2.00–1.86(m,1H),1.86–1.70(m,2H),1.6 9–1.55(m,3H),1.53–1.43(m,1H),1.42–1.37(m,1H),1.34(d,J=7.1Hz,1H),1.28(d,J=8.1Hz,1H). 13 C NMR(101MHz,Methanol-d4)δ176.28,176.11,164.79,155.84,142.36,134.35,122.12,121.81,118.03,1 11.08,65.82,57.59,54.93,36.46,35.80,31.79,30.46,29.80,28.26,26.82.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 20 H 27 N3O3,358.2125; found,358.2129.

[0137] Example 5: Synthesis of Compound P29

[0138] 1. Synthesis of intermediate M11

[0139]

[0140] Compound 2,6-dihydroxyquinoline (600 mg, 3.72 mmol) was dissolved in 30 mL of isopropanol, and DBU (1.7 mL, 11.16 mmol) was added. Then, (2R,4R)-4-bromo-2-(methoxycarbonyl)tetrahydropyrrole-1-carboxylic acid-2-methylpropyl-2-yl ester (1341 mg, 4.37 mol) was added dropwise to the system. The mixture was refluxed at 85 °C for 5 h, and the reaction was monitored by TLC. After the reaction was complete, the solvent was removed by concentration, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M11 (white solid, 156 mg, 16.1%).1 ¹H NMR (400MHz, methanol-d⁴) δ 7.94 (d, J = 9.5Hz, 1H), 7.34 (d, J = 9.8Hz, 1H), 7.29–7.18 (m, 2H), 6.64 (d, J = 9.3Hz, 1H), 5.09 (s, 1H), 4.49–4.39 (m, 1H), 3.78 (d, J = 5.9Hz, 5H), 2.60 (dd, J = 23.7, 9.8Hz, 1H), 2.35–2.21 (m, 1H), 1.45 (d, J = 6.1Hz, 9H). 2. Synthesis of intermediate M12

[0141]

[0142] M11 (156 mg, 0.46 mmol) was added to THF / H2O (40:1, 10 mL), and LiOH solid (44 mg, 1.84 mmol) was slowly added. The mixture was stirred at room temperature for 4–6 h, and the reaction was monitored by TLC. After the reaction was complete, the organic solvent was evaporated to dryness, and the pH was adjusted to 2–4 with hydrochloric acid. The resulting solution was filtered and washed with water to obtain intermediate M12 (yellow solid, 136 mg, 79.1%). 1 H NMR (400MHz, DMSO-d6) δ11.66(s,1H),7.84(d,J=9.6Hz,1H),7.25(d,J=7.3Hz,2H),7.15(d,J=9.0Hz,1H),6.49(d,J=9. 6Hz, 1H), 4.99 (s, 1H), 4.21 (q, J = 8.1Hz, 1H), 3.69–3.56 (m, 2H), 2.20 (m, J = 13.8, 7.2, 6.5Hz, 2H), 1.36 (d, J = 5.7Hz, 9H).

[0143] 3. Synthesis of intermediate M13

[0144]

[0145] Intermediate M12 (136 mg, 0.36 mmol) was dissolved in 3.0 mL of DMF, and 0.2 mL of DIPEA (1.2 mmol) was added. Then, HATU (231 mg, 0.6 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylcyclohexylamine (25 mg, 0.22 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was monitored by TLC. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product, M13 (yellow solid, 96 mg, 57.1%). 1 H NMR (400MHz, Methanol-d4) δ7.98–7.84(m,1H),7.32(m,J=9.6,4.4Hz,1H),7.21(m,J=8.1,7.7,2.9Hz,2H),6 .61(dd,J=9.3,2.5Hz,1H),5.06(m,J=6.5,3.2Hz,1H),4.91(dd,J=16.4,8.3Hz,1H),4.33(m,J=12.3,3.6Hz, 1H), 3.78(s,2H), 3.04–2.82(m,3H), 2.67–2.47(m,1H), 2.22–2.06(m,1H), 1.81(d,J=12.1Hz,2H), 1.71–1.60(m,3H), 1.41(d,J=5.0Hz,9H), 1.28(d,J=6.3Hz,1H), 1.24–1.01(m,2H), 0.95–0.80(m,2H). 4. Synthesis of target compound P29

[0146]

[0147] Intermediate M13 (96 mg, 0.2 mmol) was dissolved in 3 mL of dichloromethane, and trifluoroacetic acid (149 μL, 2 mmol) was added. After stirring at room temperature for 1 h, the solvent was removed by concentration, diluted with water, and the pH was adjusted to 6-8 with sodium bicarbonate. The mixture was then extracted with ethyl acetate, dried over anhydrous sodium sulfate, and separated by column chromatography to obtain a colorless oil product P29 (53 mg, 70.0%). 1H NMR (400MHz, Methanol-d4) δ7.93(dd,J=9.5,2.4Hz,1H),7.33(dd,J=8.6,5.9Hz,1H),7.24(dd,J =10.9,8.4Hz,2H),6.62(dd,J=9.5,2.2Hz,1H),5.11(q,J=5.3,4.8Hz,1H),4.49–4.25(m,2H),3. 63–3.52(m,1H),3.26–3.15(m,1H),2.89(d,J=28.9Hz,3H),2.59–2.34(m,1H),2.18–1.97(m,1H) ,1.84(d,J=13.2Hz,2H),1.70–1.57(m,3H),1.51(m,J=10.9,6.8,3.5Hz,1H),1.45–1.14(m,4H). 13 C NMR(101MHz,Methanol-d4)δ173.23,164.77,154.32,142.31,142.28,134.44,122.66,122.20, 118.22,112.42,79.94,58.66,55.13,53.26,38.48,37.87,31.69,30.64,29.73,28.34,26.77. HRMS(ESI-TOF)m / z:[M+H] + calcd forC 21 H 27 N3O3,370.2125; found,370.2133.

[0148] Example 6 Synthesis of compound P30

[0149] 1. Synthesis of intermediate M14

[0150]

[0151] Following the synthetic method for intermediate M11, (2R,4R)-4-bromo-2-(methoxycarbonyl)tetrahydropyrrole-1-carboxylic acid-2-methylpropyl-2-yl ester was replaced with (2S,4R)-4-bromo-2-(methoxycarbonyl)tetrahydropyrrole-1-carboxylic acid-2-methylpropyl-2-yl ester to give a colorless liquid in 75.0% yield. 1H NMR (400MHz, Methanol-d4) δ7.91 (dd, J=9.5, 2.1Hz, 1H), 7.30 (dd, J=8.8, 2.0Hz, 1H ),7.14(d,J=2.3Hz,1H),7.11(m,J=8.9,2.5Hz,1H),6.62(d,J=9.5Hz,1H),5.14–5. 04(m, 1H), 4.54–4.46(m, 1H), 3.88–3.75(m, 1H), 3.75–3.70(m, 3H), 3.64(t, J = 11.7Hz, 1H), 2.64–2.53(m, 1H), 2.46–2.41(m, 1H), 1.45(d, J = 16.4Hz, 9H). 2. Synthesis of intermediate M15

[0152]

[0153] Following the synthesis method of intermediate M12, M11 was replaced with M14 to obtain a white solid with a yield of 77.0%. 1 HNMR(400MHz,DMSO-d6)δ12.51(s,1H),11.64(s,1H),7.82(d,J=9.5Hz,1H),7 .23(d,J=8.9Hz,1H),7.17(t,J=3.5Hz,1H),7.05(m,J=7.0,3.2Hz,1H),6.49( d,J=9.5Hz,1H),4.32–4.23(m,1H),3.74(m,J=11.3,4.8Hz,1H),3.41(dd,J=1 1.8,3.9Hz,2H),2.66–2.54(m,1H),2.26–2.12(m,1H),1.38(d,J=16.7Hz,9H).

[0154] 3. Synthesis of intermediate M16

[0155]

[0156] Following the synthesis method of intermediate M13, M12 was replaced with M15 to obtain a yellow solid with a yield of 56.2%. 1HNMR(400MHz, Methanol-d4)δ7.90(m,J=9.5,2.6Hz,1H),7.32–7.26(m,1H),7.21–7.13(m,2H),6.61(d,J=9.5Hz,1H),5.06(m,J =9.7,3.3Hz,1H),4.75(m,J=17.7,8.8,3.9Hz,1H),4.28(p,J=5.8,4.4Hz,1H),3.96(m,J=11.4,5.5Hz,1H),3.65(m,J=11.0,3.6 Hz, 1H), 2.84 (dd, J = 24.9, 7.1 Hz, 3H), 2.79–2.63 (m, 1H), 2.12–2.00 (m, 1H), 1.80 (m, J = 16.2, 15.2, 10.1 Hz, 3H), 1.63 (m, J = 12.3, 3.5 Hz, 2H), 1.58–1.48 (m, 1H), 1.47–1.40 (m, 9H), 1.39–1.32 (m, 2H), 1.28 (d, J = 6.3 Hz, 1H), 1.21–1.07 (m, 1H). 4. Synthesis of target compound P30

[0157]

[0158] Intermediate M16 (95 mg, 0.2 mmol) was dissolved in 3 mL of dichloromethane, and trifluoroacetic acid (149 μL, 2 mmol) was added. After stirring at room temperature for 1 h, the solvent was removed by concentration, diluted with water, and the pH was adjusted to 6-8 with sodium bicarbonate. The mixture was then extracted with ethyl acetate, dried over anhydrous sodium sulfate, and separated by column chromatography to obtain a colorless oil product P30 (57 mg, 72.9%). 1 H NMR (400MHz, Methanol-d4) δ7.90 (dd, J=9.5, 3.3Hz, 1H), 7.32–7.26 (m, 1H), 7.20–7. 13(m,2H),6.61(d,J=9.5Hz,1H),5.00(t,J=4.6Hz,1H),4.35–4.22(m,1H),4.16–4.02 (m,1H),3.43(dd,J=13.4,4.7Hz,1H),3.05–2.95(m,1H),2.85(d,J=16.2Hz,3H),2.7 1–2.62(m,1H),1.87(s,3H),1.72–1.54(m,4H),1.46–1.31(m,3H),1.21–1.10(m,1H). 13C NMR (101MHz, Methanol-d4) δ173.29,164.81,154.03,142.32,134.50,123.04,122.17,118.11,113.13,112. 91,79.67,58.98,55.20,53.71,38.42,37.79,31.64,30.44,29.58,28.34,26.80.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 21 H 27 N3O3,370.2125; found,370.2135.

[0159] Example 6 Synthesis of compound P31

[0160] 1. Synthesis of intermediate M17

[0161]

[0162] Following the synthetic method for intermediate M12, (2R,4R)-4-bromo-2-(methoxycarbonyl)tetrahydropyrrole-1-carboxylic acid-2-methylpropyl-2-yl ester was replaced with (2S,4S)-4-bromo-2-(methoxycarbonyl)tetrahydropyrrole-1-carboxylic acid-2-methylpropyl-2-yl ester to give a colorless liquid in 72% yield. 1 H NMR(400MHz,Chloroform-d6)δ12.48(s,1H),7.73(dd,J=9.8,6.3Hz,1H),7.43–7.3 6(m,1H),7.11(dd,J=9.0,2.6Hz,1H),6.95(t,J=2.9Hz,1H),6.72(dd,J=9.5,3.6Hz, 1H), 4.98–4.87(m,1H), 4.58–4.41(m,1H), 3.80(dd,J=12.0,3.8Hz,2H), 3.76(d,J=2.3Hz,3H), 2.63–2.50(m,1H), 2.31–2.16(m,1H), 1.43(d,J=9.1Hz,9H). 2. Synthesis of intermediate M18

[0163]

[0164] Following the synthesis method of intermediate M13, M11 was replaced with M17 to obtain a white solid with a yield of 73%. 1H NMR (400MHz, DMSO-d6) δ11.68(s,1H),7.85(s,1H),7.31–7.24(m,2H),7.16(dd,J=8.8,2.9Hz,1H),6.50(t,J=8.3Hz,1H),5.0 0(t,J=4.3Hz,1H),4.22(q,J=8.3Hz,1H),3.67(d,J=12.0Hz,2H),2.48–2.39(m,1H),2.27–2.14(m,1H),1.36(d,J=5.1Hz,9H).

[0165] 3. Synthesis of intermediate M19

[0166]

[0167] Following the synthesis method of intermediate M19, M12 was replaced with M18 to obtain a white solid with a yield of 56.6%. 1 HNMR(400MHz,Methanol-d4)δ7.94–7.88(m,1H),7.37–7.30(m,1H),7.25–7.18(m,2H),6. 65–6.59(m,1H),5.11–5.02(m,1H),4.95–4.87(m,1H),4.40–4.28(m,1H),3.78(q,J=2.9Hz ,2H),2.98–2.83(m,3H),2.65–2.51(m,1H),2.20–2.11(m,1H),1.90–1.76(m,3H),1.69–1. 60(m,3H),1.41(d,J=4.9Hz,9H),1.35–1.25(m,2H),1.20–1.12(m,1H),0.91–0.83(m,1H).

[0168] 4. Synthesis of target compound P31

[0169]

[0170] Intermediate M19 (90 mg, 0.2 mmol) was dissolved in 3 mL of dichloromethane, and trifluoroacetic acid (149 μL, 2 mmol) was added. After stirring at room temperature for 1 h, the solvent was removed by concentration, diluted with water, and the pH was adjusted to 6-8 with sodium bicarbonate. The mixture was then extracted with ethyl acetate, dried over anhydrous sodium sulfate, and separated by column chromatography to obtain a colorless oil product P31 (53 mg, 72%). 1H NMR(400MHz, Methanol-d4)δ7.92(dd,J=9.5,2.4Hz,1H),7.32(dd,J=8.7,6.3Hz,1H),7.27–7.16(m ,2H),6.62(dd,J=9.5,2.5Hz,1H),5.06(t,J=5.8Hz,1H),4.39–4.20(m,2H),3.56–3.43(m,1H),3.10 (d,J=12.5Hz,1H),2.88(d,J=32.3Hz,3H),2.52–2.27(m,1H),2.12–1.99(m,1H),1.83(d,J=13.0Hz, 2H),1.68–1.59(m,3H),1.54–1.46(m,1H),1.44–1.33(m,2H),1.29–1.26(m,1H),1.20–1.09(m,1H). 13 C NMR (101MHz, Methanol-d4) δ173.91, 164.80, 154.42, 142.36, 134.41, 122.70, 122.16, 118.22, 112.82, 112. 40,80.07,58.62,55.12,53.33,38.57,37.96,31.79,30.65,29.73,28.35,26.81.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 21 H 27 N3O3,370.2125; found,370.2131.

[0171] Example 9 Synthesis of compound P32

[0172] 1. Synthesis of intermediate M20

[0173]

[0174] Following the synthesis method for M2, a white solid, M20, was obtained with a yield of 97%. 1 H NMR (400MHz, DMSO-d6) δ9.57(s,1H),7.76(d,J=9.4Hz,1H),7.41(d,J=9.1Hz,1H),7.13–6. 98(m,2H),6.52(d,J=9.4Hz,1H),4.37(t,J=7.9Hz,2H),2.53(d,J=7.9Hz,1H),2.49(s,1H).

[0175] 2. Synthesis of target compound P32

[0176]

[0177] Following the synthesis method of P1, replacing M2 with M20 yielded a yellow solid, P32, with a yield of 33.1%. 1 H NMR(400MHz,Chloroform-d)δ9.35(s,1H),7.59(d,J=9.5Hz,1H),7.42(d,J=9.1Hz,1H),7.21(d,J=9.1Hz,1H),7.09(s,1H),6.66(t,J=7.5Hz,1H),4.59( s,2H),4.39(d,J=10.7Hz,1H),2.80(d,J=20.1Hz,5H),1.75(d,J=10.9Hz,2H ),1.59(d,3H),1.45(d,J=12.2Hz,1H),1.32(s,3H),1.04(t,J=13.2Hz,1H). 13 C NMR(101MHz,Chloroform-d)δ170.52,162.22,152.89,139.51,132.48,122.25,121.26,120.51,115. 51,113.50,57.12,53.00,39.89,39.51,31.01,29.85,27.62,25.65,25.58.HRMS(ESI-TOF)m / z:[M+H] + calcd forC 19 H 24 N2O3,329.1860; found,329.1869.

[0178] Example 10 Synthesis of compound P33

[0179] 1. Synthesis of intermediate M21

[0180]

[0181] Following the synthesis method of M2, white solid M21 was obtained with a yield of 97%. 1 H NMR (400MHz, DMSO-d6) δ11.63(s,1H),7.82(d,J=9.4Hz,1H),7.23(d,J=8.9Hz,1H),7.19(s,1H),7.13(d,J=9.0H z,1H),6.48(d,J=9.4Hz,1H),3.98(t,J=6.3Hz,2H),2.28(t,J=7.2Hz,2H),1.80–1.69(m,2H),1.68–1.60(m,2H).

[0182] 2. Synthesis of target compound P33

[0183]

[0184] Following the synthesis method of P1, replacing M2 with M21 yields a yellow solid, which is P33, with a yield of 44.1%. 1 H NMR(400MHz,Chloroform-d)δ12.68(s,1H),7.73(d,J=9.5Hz,1H),7.38(d,J=9.0Hz,1H) ,7.12(d,J=8.9Hz,1H),6.96(s,1H),6.70(d,J=9.4Hz,1H),4.43(d,J=11.0Hz,1H),4.01 (s,2H),2.81(d,J=9.8Hz,3H),2.41(dd,J=19.3,8.8Hz,2H),2.01(s,1H),1.66(d,J=11. 5Hz, 2H), 1.55 (dd, J = 34.2, 11.4Hz, 2H), 1.36 (t, J = 11.6Hz, 2H), 1.08 (q, J = 13.2Hz, 1H). 13 C NMR(101MHz,Chloroform-d)δ172.21,164.29,154.71,140.64,133.20,121.76,120.79,120.60,117. 59,109.68,68.37,56.77,52.36,33.82,31.09,30.04,27.27,25.77,21.83.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 21 H 28 N₂O₃, 357.2173; found, 357.2177. Example 11 Synthesis of compounds P34-P36

[0185] 1. Synthesis of intermediate M22

[0186]

[0187] 5-Hydroxyindol-2-one (3.0 g, 0.201 mol) was dissolved in 70 mL of isopropanol, and DBU (3.4 mL, 0.242 mol) was added. Then, ethyl 4-bromobutyrate (4.6 g, 0.024 mol) was added dropwise to the system. The mixture was refluxed at 40 °C for 1 h, and the reaction was monitored by TCL. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M22 (1.0 g, 52.8%). 1 H NMR (400MHz, DMSO-d6) δ10.17(s,1H),6.84(t,J=1.5Hz,1H),6.74–6.66(m,2H),4.06(q,J=7.1Hz,2H) ,3.90(t,J=6.3Hz,2H),3.42(s,2H),2.43(t,J=7.3Hz,2H),1.97–1.88(m,2H),1.17(t,J=7.1Hz,3H).

[0188] 2. Synthesis of intermediate M23

[0189]

[0190] M22 (800 mg, 3.04 mmol) was added to THF / MeOH / H2O (3:2:1, 75 mL), and LiOH solid (292 mg, 12.2 mmol) was slowly added. The mixture was stirred at room temperature for 4–6 h, and the reaction was monitored by TCL. After the reaction was complete, the organic solvent was evaporated to dryness, and the pH was adjusted to 2–4 with hydrochloric acid. The resulting solution was filtered and washed with water to obtain M23 (yellow solid, 638 mg, 89.35%). 1 H NMR(400MHz,DMSO-d6)δ10.21(s,1H),6.84(s,1H),6.78–6.62(m,2H),3.88 (t,J=6.6Hz,2H),3.41(s,2H),2.24(t,J=7.3Hz,2H),1.87(q,J=6.8Hz,2H).

[0191] 3. Synthesis of target compound P34

[0192]

[0193] Intermediate M23 (150 mg, 0.63 mmol) was dissolved in 3.0 mL of LDMF, and 0.3 mL of DIPEA (1.9 mmol) was added. Then, 456 mg of HATU (1.2 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylaniline (81.36 mg, 0.72 mmol) was added, and the reaction was carried out at room temperature for 12 h, with TCL monitoring the reaction progress. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product, P34 (white solid, 75 mg, 36.14%). 1 H NMR (400MHz, Methanol-d4) δ6.95–6.87(m,1H),6.77(dd,J=3.0,1.4Hz,2H),4.41–4.29(m,1H),4.07–3.89(m,2H),3.48(d,J=1.1Hz,2H),2.85(d,J= 41.8Hz,3H),2.68–2.47(m,2H),2.10–1.98(m,2H),1.87–1.75(m,2H),1.7 2–1.52(m,4H),1.52–1.25(m,4H),1.14(m,J=14.7,13.1,6.6,3.0Hz,1H). 13 C NMR(101MHz,Methanol-d4)δ179.85,174.55,156.44,138.04,128.38,114.53,113.36,111.10,68 .79,58.26,54.34,31.80,31.30,30.78(2C),27.85,26.86(2C),26.72.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 19 H 26 N2O3,331.2016; found,331.2019.

[0194] 4. Synthesis of target compound P35

[0195]

[0196] Following the synthesis method of P34, N-methylaniline was replaced with N-ethylcyclohexylamine to obtain a white solid with a yield of 86%. 1H NMR(400MHz,Methanol-d4)δ6.89(d,J=5.5Hz,1H),6.77(d,J=3.8Hz,2H),3.9 7(q,J=6.2Hz,2H),3.76–3.57(m,1H),3.48(s,2H),3.38–3.30(m,2H),2.56(q ,J=7.6Hz,2H),2.15–1.96(m,2H),1.88–1.75(m,2H),1.73–1.60(m,3H),1.58 –1.44(m,2H),1.43–1.26(m,3H),1.19(t,J=7.2Hz,2H),1.11(d,J=7.1Hz,1H). 13 C NMR(101MHz,Methanol-d4)δ179.75,174.10,156.32,137.99,128.44,114.48,113.25,111.13,68.55,5 8.77,55.65,39.36,37.51,32.70,31.83,30.84,27.10,26.88,16.95,15.31.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 20 H 28 N2O3,345.2173; found,345.2180.

[0197] 5. Synthesis of target compound P36

[0198]

[0199] Following the synthesis method of P34, N-methylaniline was replaced with N-methyltetrahydro-2H-pyran-4-amine to give a white solid with a yield of 86%. 1 H NMR(400MHz, Methanol-d4)δ6.93–6.88(m,1H),6.78(dd,J=4.2,1.6Hz,2H), 4.46–4.33(m,1H),4.02–3.95(m,2H),2.91(d,J=7.7Hz,3H),2.81(s,1H),2.6 3–2.54(m,2H),2.28(s,2H),2.13(dd,J=12.1,2.5Hz,1H),2.11–2.01(m,4H) ,1.94–1.81(m,1H),1.81–1.70(m,1H),1.68–1.59(m,1H),1.59–1.54(m,1H). 13C NMR(101MHz,Methanol-d4)δ179.80,174.85,156.42,137.97,128.43,114.52,113.30,111.10 ,68.38(2C),55.24,51.63,37.51,30.72(2C),27.93,26.58,26.14.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 18 H 24 N2O4,333.1809; found,333.1812.

[0200] Example 12 Synthesis of compound P37

[0201] 1. Synthesis of intermediate M24

[0202]

[0203] 2,6-Dihydroxyquinoline (2.9 g, 0.019 mol) was dissolved in 70 mL of isopropanol, and DBU (8.6 mL, 0.057 mol) was added. Then, methyl 2-bromoethylbenzoate (3.1 mL, 0.022 mol) was added dropwise to the system. The mixture was refluxed at 85 °C for 5 h, and the reaction was monitored by TCL. After the reaction was complete, the system was diluted with water and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the product, intermediate M1. The crude product was directly added to the next step. The crude product (789 mg, 2.91 mmol) was added to THF / MeOH / H2O (3:2:1, 75 mL), and LiOH solid (360 mg, 8.73 mmol) was slowly added. The mixture was stirred at room temperature for 4-6 h, and the reaction was monitored by TCL. After the reaction was complete, the organic solvent was evaporated to dryness, hydrochloric acid was added to adjust the pH (2-4), the resulting system was filtered and washed with water, and finally a white solid M24 (510 mg, 71.4%) was obtained.

[0204] 2. Synthesis of target compound P37

[0205]

[0206] Intermediate M24 (140 mg, 0.62 mmol) was dissolved in 3.0 mL of LDMF, and 0.3 mL of DIPEA (1.9 mmol) was added. Then, 456 mg of HATU (1.2 mmol) was accurately weighed and added to the system. After stirring at room temperature for 5 min, N-methylaniline (81.36 mg, 0.72 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was monitored by TCL. After the reaction was complete, the system was diluted with water, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. Most of the solvent was removed by concentration, and the residue was separated by column chromatography to obtain the final product P37 (yellow solid, 38 mg, 20.76%). 1 H NMR(400MHz,Chloroform-d)δ12.78(s,1H),7.74(t,J=8.6Hz,1H),7.42–7.33(m,3H),7.31–7.27( m,1H),7.18(d,J=7.5Hz,1H),7.16–7.09(m,1H),7.03(dd,J=6.1,2.7Hz,1H),6.71(dd,J=9.5,2.7 Hz,1H),4.73–4.52(m,1H),4.41–4.10(m,2H),3.32–3.21(m,1H),3.07(q,J=7.3Hz,2H),3.02(s,1 H),2.67(s,2H),1.95–1.65(m,5H),1.55(s,2H),1.44(q,J=7.3,5.0Hz,2H),1.01(d,J=7.2Hz,1H). 13 C NMR(101MHz,Chloroform-d)δ171.09,164.34,154.33,140.73,137.91,137.51,134.13,133.22,130.56,128.92,126.99,126.06,1 25.53,121.67,120.60,117.56,109.81,68.58,58.33,52.36,33.29,31.38,29.78,27.19,25.70,25.16.HRMS(ESI-TOF)m / z:[M+H] + calcd for C 25 H 28 N2O3, 405.2173, found, 405.2173.

[0207] Example 13 Synthesis of compound P38

[0208] 1. Synthesis of intermediate M25

[0209]

[0210] 2-Bromo-3-pyridinecarboxaldehyde (150 mg, 0.749 mmol) and N-methylcyclohexylamine (128 mg, 1.127 mmol) were dissolved in 5 mL of toluene. [1,1-bis(diphenylphosphine)ferrocene]palladium dichloride (56 mg, 0.077 mmol), sodium tert-butoxide (14.4 mg, 0.150 mmol), and 1,1'-binaphthyl-2,2'-bisdiphenylphosphine (9.3 mg, 0.0149 mmol) were added. The mixture was refluxed at 110 °C for 4 hours under Ar protection. After the reaction was complete, the mixture was filtered through diatomaceous earth, the filtrate was diluted with water, extracted with ethyl acetate, dried over anhydrous sodium sulfate, concentrated under reduced pressure to remove the solvent, and separated by column chromatography to obtain a white solid product M25 (90 mg, 52%). 1 H NMR(400MHz,Chloroform-d)δ8.23–8.17(m,1H),7.72–7.65(m,1H),6.66–6.59(m,1H),4.05–3.96(m,1H),2.71(d,J=1.5Hz,3H),2. 48(d,J=1.5Hz,3H),1.84–1.75(m,4H),1.68–1.60(m,1H),1.49(qd,J=11.4,10.9,2.7Hz,2H),1.43–1.27(m,2H),1.17–1.04(m,1H).

[0211] 2. Synthesis of intermediate M26

[0212]

[0213] Intermediate M25 (90 mg, 0.62 mmol) was dissolved in 5 mL of acetic acid solution, and then added to 0.5 mL of acetic acid solution containing 33% HBr. 21 μL of liquid bromine (0.386 mmol) was added at 0 °C, and the reaction was carried out at 45 °C for 2 h. The reaction was monitored by TLC. After the reaction was complete, the system was diluted with water and saturated sodium bicarbonate solution, extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was removed by concentration to obtain crude product M26, which was used directly in the next reaction.

[0214] 3. Synthesis of target compound P38

[0215]

[0216] Intermediate M26 (60 mg, 0.193 mmol) was dissolved in DMF (4 mL), and 2,6-dihydroxyquinoline (26 mg, 0.161 mmol) and potassium carbonate (32 mg, 0.231 mmol) were added and reacted for 1 h. After the reaction was completed, the system was diluted with water, extracted with ethyl acetate, dried over anhydrous sodium sulfate, concentrated under reduced pressure to remove the solvent, and purified by column chromatography to give a yellow solid (20 mg, 98%). 1 H NMR(400MHz,Chloroform-d)δ12.54(s,1H),8.31–8.22(m,1H),7.86–7.79(m,1H ),7.72(d,J=9.5Hz,1H),7.38(d,J=8.9Hz,1H),7.22–7.15(m,1H),7.00(d,J=2. 7Hz,1H),6.74–6.64(m,2H),5.10(s,2H),4.23–4.08(m,1H),2.67(s,3H),1.78( d,J=10.5Hz,4H),1.65(d,J=12.6Hz,1H),1.54–1.38(m,3H),1.39–1.32(m,2H). 13 C NMR(101MHz,Chloroform-d)δ196.70,164.31,159.47,153.76,150.88,140.56,139.26,133.78,122.10,120.72, 120.54,117.89,117.81,112.56,110.62,71.76,59.32,34.54,29.98(2C),25.97(2C).HRMS(ESI-TOF)m / z:[M+H] + calcd for C 23 H 25 N3O3, 392.1969, found, 392.1973. Example 14: Study on the inhibitory activity of the target compound against phosphodiesterase type 3 (PDE3) enzyme.

[0217] Determination of required enzyme concentration: Prepare a series of enzyme solutions with gradient concentrations using Assay Buffer (2.0 mM magnesium chloride, 50 mM Tris 7.5, 1.0 mM DTT). Take 40 μL of each solution and add 60 μL of diluted substrate. For the negative control, use 40 μL of Assay Buffer instead of the enzyme solution. React at room temperature for 15 min. Add 200 μL of 0.2 M zinc sulfate solution and 200 μL of 0.2 M barium hydroxide solution to terminate the reaction. Centrifuge at 14000 rpm for 5 min, take 430 μL of the supernatant, transfer it to a scintillation tube containing 2.5 mL of scintillation fluid, vortex to mix thoroughly, and test using a scintillation analyzer.3 The enzyme concentration required for the assay is the one with a hydrolysis rate of 40%-70% for H]-cAMP.

[0218] Assay for the inhibitory activity of the test compound against the enzyme: Take 2.0 μL of the test compound in DMSO solution and add it to 58 μL of diluted substrate, mix thoroughly; add 2.0 μL of ciproamide in DMSO solution for the positive control. Then add 40 μL of enzyme solution with a suitable hydrolysis range, and add 40 μL of Assay Buffer instead of enzyme solution for the negative control. React at room temperature for 15 min. The reaction is terminated as above. Take 430 μL of the supernatant and transfer it to a scintillation tube containing 2.5 mL of scintillation solution, mix thoroughly, and then measure using a scintillation analyzer. The inhibitory activity of the compound against the enzyme is expressed as the half-maximal inhibitory concentration (IC50). 50 The positive control drug was siloxane, and the results are shown in Table 1.

[0219] Table 1. Results of the inhibitory activity test of 2-hydroxy-6-alkoxyquinoline compounds against PDE3 enzyme.

[0220]

[0221]

[0222] As shown in the table, at a concentration of 100 nM, most compounds exhibit good inhibitory activity against the target protein, with inhibition rates ranging from 30% to 100%. Among them, the preferred compounds P1, P6, and P28 show superior inhibitory activity against the target protein PDE3 compared to the positive control drug milrinone, making them potent PDE3 inhibitors.

[0223] Example 15: Water solubility test of compound P28 and ciloxamide

[0224] Accurately weigh 0.0012 g of compound P28, completely dissolve it in 1.0 mL of HPLC-grade methanol, and prepare solutions with concentrations of 1.2, 0.6, 0.3, 0.15, and 0.075 mg / mL, respectively. Inject the standard sequentially using the same sampling method to establish a standard curve as shown below. Figure 1 As shown. The linear fitting function is: f(x)=1.92090e+006x+0

[0225] P28 was dissolved in distilled water until the solution was saturated. After injection using the same injection method, the peak area was substituted into the fitted curve, and the water solubility of compound P28 was found to be 26.667 mg / mL.

[0226] Accurately weigh 0.0027 g of ciloxamide and completely dissolve it in 1.0 mL of HPLC-grade methanol to prepare solutions with concentrations of 2.7, 1.4, 0.7, 0.35, and 0.175 mg / mL, respectively. Inject the standard solutions sequentially using the same sampling method to establish a standard curve as shown below. Figure 2 As shown. The linear fitting function is: f(x)=y=6.44184e+006x+0

[0227] Ciproamide was dissolved in distilled water until the solution was saturated. After injection using the same injection method, the peak area was substituted into the fitted curve, and the water solubility of ciproamide was found to be 0.866 mg / mL.

[0228] from Figure 1 and Figure 2 As can be seen from the present invention, the novel series of compounds P28 obtained after structural optimization of ciloxamide has excellent water solubility, with a water solubility of 26.667 mg / mL, which is significantly better than the water solubility of ciloxamide (0.866 mg / mL).

[0229] Example 16: Study on the liver microsomal stability of compound P28

[0230] Liver microsomes were incubated at 37°C for 10 min in 0.1 M PBS buffer (pH 7.4, final concentration 0.5 mg / mL), cofactor MgCl2 (final concentration 5 mM), the analyte (final concentration 1 μM), cosolvent (0.01% DMSO), and 0.005% Bovin serum albumin (BSA). NADPH (final concentration 1 mM) was added at the start of the reaction. Samples were aliquoted at 0, 7, 17, 30, and 60 min, and the reaction was terminated by adding acetonitrile (cooled to 4°C). After centrifugation (4000 rpm, 5 min), LC-MS / MS analysis was performed. The results of the liver stability test are shown in Table 2.

[0231] Table 2. Results of the test on the stability of compound P28 in rat liver microsomes.

[0232] compound <![CDATA[Hepatic microsomal stability, half-life t 1 / 2 (min)]]> P28 49.1 Ciproamide 11.0

[0233] Therefore, the novel series of compounds P28 obtained by structural optimization of cilamide in this invention has a liver microsomal stability half-life of 49.1 min, which is significantly better than the 11.0 min of the positive compound cilamide.

[0234] Example 17: Pharmacokinetic Study of Compound P28 in Rats

[0235] Rats were administered compound P28 via gavage and intravenous injection, respectively. The plasma concentration over time was observed, and the corresponding pharmacokinetic parameters and absolute bioavailability were estimated. The determination process and results are as follows:

[0236] (1) Measurement process

[0237] Six rats were randomly divided into two groups, receiving P28 intravenously and by gavage, respectively. In the intravenous injection group, blood samples (approximately 0.25 mL) were collected via the jugular vein at 5 min, 15 min, 30 min, 1 h, 2 h, 4 h, 6 h, 8 h, and 24 h after administration. The concentration of LWDJ-2414 in rat plasma samples was determined using LC-MS / MS, and pharmacokinetic parameters were calculated using WinNolin software.

[0238] (2) Measurement results

[0239] Following a single intravenous injection of 2.5 mg / kg P28 and gavage administration of 5 mg / kg P28 in rats, the main pharmacokinetic parameters after intravenous administration were: C max The concentration was 2147 ng / mL, T max It is 0.0833h, T 1 / 2 The AUC is 3.39h. 0-t The concentration was 1598 hr*ng / mL, and the AUC was... 0-∞ The concentrations were 1611 hr*ng / mL, Vz was 8340 mL / kg, Cl was 1603 mL / hr / kg, and MRT was... 0-t For 1.33 hours, MRT 0-∞ The duration of administration was 1.52 h. The main pharmacokinetic parameters for gavage administration were: C max The concentration was 906 ng / mL, T max For 0.250h, T 1 / 2 The AUC is 3.11h. 0-t 2170 hr*ng / mL, AUC 0-∞ 2246hr*ng / mL, MRT 0-t For 3.21 hours, MRT 0-∞ The duration of action was 3.69 h, and the oral bioavailability was 69.7%. Test parameters are shown in Table 3, and the blood drug concentration curve is shown in... Figure 3 , Figure 4 As shown.

[0240] Table 3. Results of in vivo pharmacokinetic studies of P28 in rats

[0241]

[0242] Therefore, the novel series of compounds P28 obtained by structural optimization of siloxane in this invention have good oral bioavailability (69.7%).

[0243] The above results demonstrate that the 2-hydroxy-6-alkoxyquinoline compounds of this invention exhibit good inhibitory activity against phosphodiesterase type 3 (PDE3), excellent water solubility, liver microsomal stability, and oral bioavailability, fully illustrating the good drug-like properties of this class of 2-hydroxy-6-alkoxyquinoline compounds. Therefore, the 2-hydroxy-6-alkoxyquinoline compounds of this invention have broad application potential as inhibitors of phosphodiesterase type 3.

[0244] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A 2-hydroxy-6-alkoxyquinoline compound, characterized in that, The 2-hydroxy-6-alkoxyquinoline compounds have the following structure (I) or (II): （I）， （Ⅱ）； Where R1 and R2 are each independently selected from C 1～6 Non-substituted alkyl, cyclohexyl; m is 1; n is 1; X is -CH=CH-; Y is -C(O)-; Z is -N-.

2. The 2-hydroxy-6-alkoxyquinoline compound as described in claim 1, characterized in that, R1 and R2 are each independently selected from methyl, ethyl, propyl, isopropyl, butyl, and cyclohexyl.

3. A pharmaceutically acceptable salt of a 2-hydroxy-6-alkoxyquinoline compound as described in any one of claims 1 to 2.

4. Use of the 2-hydroxy-6-alkoxyquinoline compound as described in any one of claims 1 to 2 or the pharmaceutically acceptable salt as described in claim 3 in the preparation of an inhibitor, medicament, or pharmaceutical composition for the prevention, treatment, or adjunctive treatment of diseases related to PDE3 activity or expression.

5. The use as described in claim 4, characterized in that, The diseases described are immune and inflammatory diseases related to PDE3 activity or expression levels.

6. The use as described in claim 4, characterized in that, The diseases associated with PDE3 activity or expression levels are heart failure, myocardial infarction, arrhythmia, and bronchodilation.

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