Aromatic amino acid derivatives as lat1 inhibitors, and methods of making and using the same

Abstract

The application discloses an aromatic amino acid derivative as a LAT1 inhibitor, characterized in that the derivative comprises a compound as shown in a structural formula (I), or a stereoisomer thereof, or a pharmaceutically acceptable salt thereof; the aromatic amino acid derivative of the application can efficiently inhibit LAT1 activity, thereby inhibiting the activation of T cells, and relieving or treating immune-related diseases including cancer or inflammation caused by excessive activation of T cells.

Description

TECHNICAL FIELD

[0001] The present application relates to an aromatic amino acid derivative, in particular to an aromatic amino acid derivative as a LAT1 inhibitor, and to the preparation and use of the derivative. BACKGROUND

[0002] Transporters, as transmembrane proteins, facilitate the movement of substrates across biological membranes, and they regulate cellular uptake and / or efflux of different molecules, including ions, nutrients such as glucose, amino acids and lipids, and neurotransmitters, to maintain cellular homeostasis and function. Compared to normal cells, tumor cells require more nutrients and amino acids to support the high rate of protein synthesis and cellular metabolism, ultimately leading to rapid tumor cell growth, proliferation and survival. Therefore, tumor cells usually significantly upregulate the expression level of transporters to meet their excessive growth and proliferation needs, which makes inhibiting cancer-specific nutrient transporters an effective therapeutic strategy.

[0003] Among the numerous amino acid transporters significantly upregulated in cancer cells, LAT1 has attracted much attention from researchers due to its tumor-specific expression. LAT1 (L-type amino acid transport 1) mainly transports neutral and bulky amino acids into cells in a sodium-independent manner, and it is mainly expressed in the placenta, testis, ovary, and blood-brain barrier, glial cells in normal organisms. In addition, LAT1 is significantly overexpressed in cancer organisms and is highly tumor cell-specific. Numerous studies have shown that overexpression of LAT1 is associated with poor prognosis and survival in various cancers, such as breast cancer, prostate cancer, lung cancer, colorectal cancer, head and neck cancer, and glioma. Inhibition of LAT1 by small molecule inhibitors or gene knockout significantly reduces the uptake of key amino acids by tumor cells and effectively inhibits tumor cell proliferation. Therefore, inhibiting LAT1 to inhibit the uptake of key amino acids by tumor cells is a very promising anticancer strategy.

[0004] Immune cells also exhibit increased metabolic demand when activated, and activated T cells exhibit aggressive proliferation and massive cytokine production. LAT1 can transport amino acids required for T cell activation and also acts as a signal transduction molecule for T cell activation. Inhibition of LAT1 can inhibit T cell activation and effectively alleviate immune-related diseases caused by excessive T cell activation.

[0005] The most widely studied small molecule inhibitor of LAT1 is JPH-203, which is currently in the third phase of clinical trials for the treatment of advanced biliary tract cancer. JPH-203 has shown good antitumor effects in various mouse solid tumor models, with an IC 50The cell proliferation inhibition IC50 is 4.1 μM, showing good LAT1 inhibition activity and selectivity. In addition, JPH-203 shows good anti-inflammatory effect in various mouse inflammation models, and JPH-203 can effectively alleviate and inhibit the development and deterioration of various inflammations. However, the aniline group in the structure of the compound is easily acetylated in the liver in the human body, resulting in a decrease in activity and rapid excretion through bile, resulting in dose-limiting liver toxicity side effects in some subjects in clinical trials, so that the indications of JPH-203 are limited to biliary tract cancer. SUMMARY

[0006] The present application aims to provide an aromatic amino acid derivative as a LAT1 inhibitor with high safety and strong efficacy, and also provides a preparation method and application of the derivative.

[0007] Technical solution: The aromatic amino acid derivative as a LAT1 inhibitor of the present application comprises a compound as shown in structural formula (I) or a stereoisomer thereof or a pharmaceutically acceptable salt thereof:

[0008]

[0009] wherein R 1 is selected from H, halogen, OH, NH2, CN, C1-C6 alkyl, C2-C6 alkynyl, C2-C6 alkenyl, C3-C6 cycloalkyl, C6-C 10 aryl, 4-7-membered heterocyclyl or 5-10-membered heteroaryl; the OH, NH2, C1-C6 alkyl, C2-C6 alkynyl, C2-C6 alkenyl, C3-C6 cycloalkyl, C6-C 10 aryl, 4-7-membered heterocyclyl or 5-10-membered heteroaryl is substituted by R 1a , R 1a is selected from halogen, OH, NH2, CN, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylamino, -C(O)-C1-C6 alkyl or -S(O)2-C1-C6 alkyl.

[0010] R 2 , R 3 is selected from H or C1-C6 alkyl;

[0011] R 4 is selected from H or halogen;

[0012] R 5 is selected from H, halogen, OH, NH2, CN, C1-C6 alkyl, phenyl or 5-6-membered heteroaryl, and the OH, NH2, C1-C6 alkyl, phenyl or 5-6-membered heteroaryl is substituted by R 5a ; R 5aSelected from halogens, OH, NH2, CN, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylamino, phenyl, or 5-6 heteroaryl groups;

[0013] L is selected from -O-L1- or -NH-L1-, and L1 is selected from CH2 or

[0014] Ring A is selected from C6-C 10 Aryl, 5-10 heteroaryl or C3-C 12 cycloalkyl;

[0015] m and p are selected from 0, 1, 2, 3 or 4; n is selected from 0, 1, 2, 3, 4 or 5.

[0016] In the derivative structural formula, R 1 Selected from H, halogen, OH, NH2, CN, C1-C6 alkyl, C2-C6 alkynyl, or phenyl, wherein the OH, NH2, C1-C6 alkyl, C2-C6 alkynyl, or phenyl is R 1a Replace, R 1a Selected from F, CN, CH3, CF3, -COCH3 or -S(O)2CH3.

[0017] In the derivative structural formula, R 2 R 3 Selected from H or CH3.

[0018] In the derivative structural formula, R 4 Selected from H or Cl.

[0019] In the derivative structural formula, R 5 Independently selected from H, halogens, OH, CN, CH3, C(CH3)3, The OH, CN, CH3, R 5a Replace, R 5a Selected from halogens, C1-C6 haloalkyl groups, or phenyl groups.

[0020] Among them, ring A is selected from

[0021] Where m is 1, n is 1 or 2, and p is 2.

[0022] The derivatives include compounds of formula (II) or formula (III) or their stereoisomers or their pharmaceutically acceptable salts:

[0023]

[0024] Among them, R1 , R 2 , R 3 , R 4 , R 5 , L or ring A is as defined above.

[0025] wherein the derivative comprises a compound of formula (II-1) or formula (III-1) or a stereoisomer thereof or a pharmaceutically acceptable salt thereof:

[0026]

[0027] wherein R 1 , R 2 , R 3 , R 4 , R 5 , L or ring A is as defined above.

[0028] wherein the aromatic amino acid derivative or a stereoisomer thereof or a pharmaceutically acceptable salt thereof comprises the following structural formula:

[0029]

[0030]

[0031]

[0032] The aromatic amino acid derivative represented by the above formula (I) is prepared by the following method:

[0033]

[0034] A pharmaceutical composition comprising the aromatic amino acid derivative represented by the above formula (I) or a stereoisomer thereof or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable excipient.

[0035] Use of the aromatic amino acid derivative, or a stereoisomer thereof or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition thereof in the preparation of a medicament for preventing or treating a LAT1-mediated disease.

[0036] wherein the use for preventing or treating a LAT1-mediated disease comprises administering to a mammal in need of such treatment a therapeutically effective amount of the compound of formula (I) or a stereoisomer thereof or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition thereof.

[0037] wherein the LAT1-mediated disease is cancer or inflammation.

[0038] Invention Principle: Using L-tyrosine, a substrate with high affinity for LAT1, as the basic backbone, fragment derivatization was performed. By introducing different large-volume hydrophobic fragments, a series of small-molecule inhibitors with good LAT1 inhibitory activity were obtained. These inhibitors possess high LAT1 affinity and can effectively occupy the protein-binding cavity of LAT1, interfering with LAT1's transport of amino acids. These compounds effectively inhibit the uptake of key amino acids by tumor cells or activated T cells by inhibiting LAT1. Leucine, as a key signaling molecule for activating the intracellular mTOR signaling pathway, is inhibited when cellular uptake of leucine is suppressed, thereby inhibiting the growth and proliferation of tumor cells or activated T cells. Therefore, the aromatic amino acid derivatives of this invention can effectively inhibit the uptake of nutrients by tumor cells, causing tumor "starvation," and can be used for anti-tumor therapy. Simultaneously, these aromatic amino acid derivatives can effectively inhibit the proliferation and differentiation of activated T cells, alleviating immune-related diseases caused by excessive T cell activation.

[0039] Beneficial effects: Compared with the prior art, the present invention has the following advantages: The aromatic amino acid derivatives of the present invention have good drug-like properties and can efficiently and selectively inhibit LAT1, thereby inhibiting the uptake of amino acids by tumor cells or activated T cells and thus inhibiting cell growth and proliferation, effectively treating cancer or immune-related diseases; at the same time, due to the specific expression of LAT1 under this pathological condition relative to normal tissues, the aromatic amino acid derivatives of the present invention, as selective LAT1 inhibitors, can ensure good therapeutic effects while having high safety in inflammatory diseases. Detailed Implementation

[0040] The technical solution of the present invention will be further described below with reference to the embodiments.

[0041] All reagents used in this invention are commercially available. Compounds are prepared manually or... Software naming conventions were used; commercially available compounds adopted supplier catalog names. The structures of the compounds were determined using nuclear magnetic resonance (NMR) and / or mass spectrometry (MS). NMR shifts were measured in units of 10⁻¹⁰. -6 (ppm). The solvents used for NMR determination include deuterated dimethyl sulfoxide, deuterated chloroform, and deuterated methanol, with tetramethylsilane (TMS) as the internal standard. The eluent can be a mixture of two or more solvents, with the ratio being the volume ratio of each solvent. For example, "petroleum ether: ethyl acetate = 3:1" indicates that in the gradient elution process, the volume ratio of petroleum ether to ethyl acetate in the mixed eluent is 3:1.

[0042] Example 1: Compound LBS-1

[0043]

[0044] Step one: Dissolve the starting material 5-bromosalicylaldehyde (1 g, 5 mmol) and 4-fluorobenzyl bromide (0.98 g, 5.25 mmol) in 10 ml of acetone, then add potassium carbonate (1.38 g, 10 mmol), heat to reflux and stir for 5 h, monitor the reaction completion by TLC. Cool to room temperature, remove the potassium carbonate by suction filtration and concentrate the resulting filtrate under vacuum to give a light yellow oil. Add petroleum ether to slurry to give 5-bromo-2-((4-fluorobenzyl)oxy)benzaldehyde (white solid, 1.4 g, 94% yield). The product is used directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 14 H 11 BrFO2 + Calculated 308.9921, found 308.9930.

[0045] Step two: Dissolve 5-bromo-2-((4-fluorobenzyl)oxy)benzaldehyde (1 g, 3.2 mmol) in 10 ml of methanol, cool to 0-5 °C. Slowly add sodium borohydride (0.13 g, 3.5 mmol) at 0-5 °C, a large amount of gas is released during the dropwise addition, after the dropwise addition, raise the temperature to room temperature and react for 0.5 h. After the reaction is completed by TLC, adjust the pH of the mixture to 8-9 by adding saturated sodium bicarbonate solution, add dichloromethane and separate the organic phase. Extract the aqueous phase with dichloromethane twice, combine the organic phases, wash with saturated brine and dry over anhydrous sodium sulfate for 2 h. Concentrate the filtrate obtained by suction filtration under vacuum to give (5-bromo-2-((4-fluorobenzyl)oxy)phenyl)methanol (white solid, 1 g, 98% yield). The product is used directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 14 H 13 BrFO2 + Calculated 311.0078, found 311.0065.

[0046] Step three: Dissolve (5-bromo-2-((4-fluorobenzyl)oxy)phenyl)methanol (1 g, 3.2 mmol) in 10 ml dichloromethane, cool down to -10-0 °C. Slowly add phosphorus tribromide (0.95 g, 3.5 mmol) in dichloromethane solution at 0-5 °C, keep the temperature at -10 °C-0 °C during the addition. After the addition, let it warm up to room temperature for 1 h, monitor the reaction by TLC. Add saturated aqueous sodium bicarbonate solution to adjust the pH to 8-9, separate the organic phase. Extract the aqueous phase with dichloromethane twice, combine the organic phase, wash with saturated brine, dry over anhydrous sodium sulfate and concentrate, purify by silica gel column chromatography (petroleum ether: ethyl acetate = 5: 1) to give 4-bromo-2-(bromomethyl)-l-((4-fluorobenzyl)oxy)benzene (white solid, 0.8 g, yield 66.7%). HRMS (ESI): m / z (M+H) + .C 14 H 12 Br2FO + Calculated 374.9213, found 374.9199.

[0047] Step four: Dissolve the starting material L-tyrosine methyl ester (1 g, 5.1 mmol) in 20 ml acetic acid, slowly add sulfuryl chloride (1.7 g, 12.7 mmol) at room temperature, keep the temperature of the reaction solution at 25-35 °C. After the addition, let it react for 5 h, monitor the reaction by TLC. Cool down the reaction solution to 0-5 °C. Slowly add 8 M sodium hydroxide aqueous solution to adjust the pH to 7-8, a large amount of solid precipitates. Filter the solid and wash with a small amount of methanol to give (S)-2-amino-3-(3,5-dichloro-4-hydroxyphenyl)propanoic acid methyl ester (white solid, 0.8 g, yield 81%). Use it directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 10 H 12 Cl2NO3 + Calculated 264.0189, found 264.0192.

[0048] Step five: (S)-2-amino-3-(3,5-dichloro-4-hydroxyphenyl)propionic acid methyl ester (0.6 g, 2.2 mmol) was dissolved in 6 ml of methanol, di-tert-butyl dicarbonate (0.54 g, 2.5 mmol) and triethylamine (0.34 g, 3.4 mmol) were added at room temperature and stirred for 4 h. After TLC monitoring the reaction was complete, water and dichloromethane were added and the organic phase was separated. The aqueous phase was extracted twice with dichloromethane and the organic phases were combined. It was washed once with 1 N dilute aqueous hydrochloric acid, once with saturated brine, dried over anhydrous sodium sulfate and concentrated. After trituration with petroleum ether, (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4- hydroxyphenyl)propionic acid methyl ester was obtained as a white solid (0.74 g, 90% yield). It was used directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 15 H 20 Cl2NO5 + Calculated 364.0714, found 364.0708.

[0049] Step six: 4-bromo-2-(bromomethyl)-l-((4-fluorobenzyl)oxy)benzene (0.37 g, 1 mmol) and (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-hydroxyphenyl)propionic acid methyl ester (0.36 g, 1 mmol) were dissolved in 5 ml of N,N-dimethylformamide, cesium carbonate (0.65 g, 2 mmol) was added and the reaction was carried out at room temperature for 2 h. After TLC monitoring the reaction was complete, water and ethyl acetate were added and the organic phase was separated. The aqueous phase was extracted twice with ethyl acetate and the organic phases were combined. It was washed with saturated brine, dried over anhydrous sodium sulfate and concentrated, and (S)-3-(4-((5-bromo-2-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propionic acid methyl ester was obtained as a white solid (0.45 g, 68.7% yield) by silica gel column chromatography (petroleum ether: ethyl acetate = 4: 1). HRMS (ESI): m / z (M+H) + .C 29 H 30 BrCl2FNO6 + Calculated 656.0613, found 656.0610.

[0050] Step seven: (S)-3-(4-((5-bromo-2-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (0.4 g, 0.6 mmol) was dissolved in 4 ml tetrahydrofuran, 2M sodium hydroxide aqueous solution (0.6 ml, 1.2 mmol) was added slowly into the solution, the reaction was allowed to proceed at room temperature for 4 h. TLC monitoring reaction was complete, 2N dilute hydrochloric acid aqueous solution was added slowly to adjust pH to 2-3, water and dichloromethane were added, the organic phase was separated. The aqueous phase was extracted with dichloromethane twice, the organic phase was combined, washed with saturated brine, dried over anhydrous sodium sulfate and concentrated to give (S)-3-(4-((5-bromo-2-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (transparent oil, 0.37 g, yield 94.8%). It was used directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 28 H 28 BrCl2FNO6 + Calculated 642.0456, found 642.0455.

[0051] Step eight: (S)-3-(4-((5-bromo-2-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (0.3 g, 0.46 mmol) was dispersed in 4 ml 1,4-dioxane, and cooled to 0-5 °C. 4M hydrogen chloride solution in 1,4-dioxane (1.1 ml, 4.6 mmol) was added slowly dropwise, and the reaction was allowed to proceed at room temperature for 12 h. TLC monitoring reaction was complete, the solvent was removed by vacuum concentration. Ethyl acetate was added to make a slurry, and LBS-1, (S)-2-amino-3-(4-((5-bromo-2-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5- dichlorophenyl)propanoic acid (white solid, 0.18 g, yield 72%) was obtained by filtration. 1 H NMR (300 MHz, DMSO-d6): δ = 8.58 (br, 2H), 7.68 (d, J = 3 Hz, 2H), 7.57-7.46 (m, 5H), 7.25-7.12 (m, 3H), 5.12 (s, 2H), 5.02 (s, 2H), 4.24 (t, J = 6 Hz, 1H), 3.26-3.09 (m, 1H) ppm. HRMS (ESI): m / z (M+H) + .C 23 H 20 BrCl2FNO4 + Calculated 541.9932, found 541.9910.

[0052] Example 2-23 was prepared according to the procedures and routes described in Example 1.

[0053] Example 2: Compound LBS-2

[0054]

[0055] Example 2-23 was prepared according to the procedures and routes described in Example 1. 1 H NMR (300 MHz, DMSO-d6): δ = 8.58 (br, 2H), 7.60-7.58 (m, 2H), 7.57-7.54 (m, 1H), 7.53-7.48 (m, 2H), 7.46-7.43 (m, 3H), 7.39-7.36 (m, 1H), 7.17-7.14 (m, 4H), 6.98 (d, J = 6 Hz, 1H), 5.15 (s, 2H), 5.10 (s, 2H), 4.12 (t, J = 6 Hz, 1H), 3.31-3.20 (m, 1H) ppm. HRMS (ESI): m / z (M+H) + .C 29 H 25 Cl2FNO4 + Calculated 540.1140, found 540.1138.

[0056] Example 3: Compound LBS-3

[0057]

[0058] Example 2-23 was prepared according to the procedures and routes described in Example 1. 1H NMR (300 MHz, DMSO-d6): δ = 8.55 (br, 2H), 7.58-7.55 (d, J = 9 Hz, 2H), 7.45 (s, 1H), 7.38 (d, J = 9 Hz, 2H), 7.15 (d, J = 3 Hz, 1H), 7.07 (d, J = 9 Hz, 1H), 6.96-6.91 (m, 1H), 5.11 (s, 2H), 5.04 (s, 2H), 4.23 (t, J = 6 Hz, 1H), 3.74 (s, 1H), 3.25-3.07 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 23 Cl2F3NO6 + Calculated 560.0850, found 560.0905.

[0059] Example 4: Compound LBS-4

[0060]

[0061] LBS-4, (2S)-2-amino-3-(3,5-dichloro-4-(l-(5-cyano-2-((4-fluorobenzyl)oxy)phenyl)ethoxy)phenyl)propanoic acid, was prepared using the same preparation method as LBS-1, with 2-acetyl-4-cyanophenol and 4-fluorobromobenzyl as starting materials, respectively. 1 H NMR (300 MHz, DMSO-d6): δ = 8.55 (br, 2H), 7.58-7.55 (d, J = 9 Hz, 2H), 7.45 (s, 1H), 7.38 (d, J = 9 Hz, 2H), 7.15 (d, J = 3 Hz, 1H), 7.07 (d, J = 9 Hz, 1H), 6.96-6.91 (m, 1H), 5.11 (s, 2H), 5.04 (s, 2H), 4.23 (t, J = 6 Hz, 1H), 3.74 (s, 1H), 3.25-3.07 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 22 Cl2FN2O4 + Calculated 503.0936, found 503.0939.

[0062] Example 5: Compound LBS-5

[0063]

[0064] Using 2-hydroxy-5-methoxybenzaldehyde and 3-(bromomethyl)-1,1'-biphenyl as starting materials, respectively, LBS-6, (S)-3-(4-((2-([1,1'-biphenyl]-3- ylmethoxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)-2-aminopropanoic acid, was prepared by the same method as LBS-1, as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.61 (br, 2H), 7.56-7.44 (m, 5H), 7.32 (d, J = 6 Hz, 1H), 7.15 (d, J = 3 Hz, 1H), 7.07 (d, J = 9 Hz, 1H), 6.96-6.92 (m, 1H), 5.15 (s, 1H), 5.05 (s, 1H), 4.23 (t, J = 6 Hz, 1H), 3.74 (s, 1H), 3.26-3.10 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 23 Cl2F3NO6 + Calculated 560.0850, found 560.0446.

[0065] Example 6: Compound LBS-6

[0066]

[0067] Using 2-hydroxy-5-methoxybenzaldehyde and 3-(bromomethyl)-1,1'-biphenyl as starting materials, respectively, LBS-6, (S)-3-(4-((2-([1,1'-biphenyl]-3- ylmethoxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)-2-aminopropanoic acid, was prepared by the same method as LBS-1, as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.61 (br, 2H), 7.56-7.44 (m, 5H), 7.32 (d, J = 6 Hz, 1H), 7.15 (d, J = 3 Hz, 1H), 7.07 (d, J = 9 Hz, 1H), 6.96-6.92 (m, 1H), 5.15 (s, 1H), 5.05 (s, 1H), 4.23 (t, J = 6 Hz, 1H), 3.74 (s, 1H), 3.26-3.10 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 30 H 28 Cl2NO5 + Calculated 552.1340, found 552.1335.

[0068] Example 7: Compound LBS-7

[0069]

[0070] Using the same preparation method as LBS-1 with 2-hydroxy-5- (trifluoromethoxy)benzaldehyde and 4-trifluoromethoxybenzyl bromide as starting materials, respectively, LBS-7, (S)-2-amino-3-(3,5-dichloro-4-((5- (trifluoromethoxy)-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared as a white solid. 1 HNMR (300 MHz, DMSO-d6): δ = 8.49 (br, 2H), 7.57-7.50 (m, 3H), 7.42-7.36 (m, 5H), 7.22 (d, J = 9 Hz, 1H), 5.18 (s, 2H), 5.05 (s, 2H), 4.18 (t, J = 7.5 Hz, 1H), 3.21-3.03 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + . 25 H 20 Cl2F6NO6 + Calculated 614.0567, found 614.0013.

[0071] Example 8: Compound LBS-8

[0072]

[0073] Using the same preparation method as LBS-1 with 2-hydroxy-5- (trifluoromethoxy)benzaldehyde and 4-trifluoromethoxybenzyl bromide as starting materials, respectively, LBS-7, (S)-2-amino-3-(3,5-dichloro-4-((5- (trifluoromethoxy)-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared as a white solid. 1 HNMR (300 MHz, DMSO-d6): δ = 8.49 (br, 2H), 7.57-7.50 (m, 3H), 7.42-7.36 (m, 5H), 7.22 (d, J = 9 Hz, 1H), 5.18 (s, 2H), 5.05 (s, 2H), 4.18 (t, J = 7.5 Hz, 1H), 3.21-3.03 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + . 25 H 22 Cl2F4NO5 +Calculated 562.0806, found 562.0904.

[0074] Example 9: Compound LBS-9

[0075]

[0076] Using the same preparation method as LBS-1, with 2-bromo-5-hydroxybenzaldehyde and 4-trifluoromethoxybenzyl bromide as starting materials respectively, LBS-9, (S)-2-amino-3-(4-((5-bromo-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a light yellow solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.61 (br, 2H), 7.68 (d, J = 3 Hz, 1H), 7.58-7.53 (m, 3H), 7.46 (s, 2H), 7.38 (d, J = 9 Hz, 2H), 7.13 (d, J = 9 Hz, 1H), 5.17 (s, 2H), 5.03 (s, 2H), 4.24 (t, J = 6 Hz, 1H), 3.26-3.09 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + . 24 H 20 BrCl2F3NO5 + Calculated 607.9849, found 609.6681.

[0077] Example 10: Compound LBS-10

[0078]

[0079] Using the same preparation method as LBS-1, with 2-methyl-5-hydroxybenzaldehyde and 4-trifluoromethoxybenzyl bromide as starting materials respectively, LBS-10, (S)-2-amino-3-(3,5-dichloro-4-((5-methyl-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.51 (br, 2H), 7.59-7.56 (m, 2H), 7.44 (s, 2H), 7.40-7.35 (m, 2H), 7.19-7.15 (m, 1H), 7.03 (d, J = 9 Hz, 1H), 5.14 (s, 2H), 5.02 (s, 2H), 4.24 (t, J = 6 Hz, 1H), 3.23-3.06 (m, 2H), 2.29 (s, 3H) ppm. HRMS (ESI): m / z (M+H) + .25 H 23 Cl2F3NO5 + Calculated 544.0900, found 544.1124.

[0080] Example 11: Compound LBS-11

[0081]

[0082] Using 2-hydroxy-5-methoxybenzaldehyde and 2-bromomethylquinoline as starting materials, respectively, LBS-11, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-2-(quinolin-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid, was prepared as a white solid using the same preparation method as LBS-1. 1 H NMR (300 MHz, DMSO-d6): δ = 8.75 (d, J = 9 Hz, 1H), 8.59 (br, 2H), 8.26 (d, J = 9 Hz, 1H), 8.17 (d, J = 6 Hz, 1H), 7.96 (t, J = 7.5 Hz, 1H), 7.86 (d, J = 9 Hz, 1H), 7.77 (t, J = 7.5 Hz, 1H), 7.43 (s, 2H), 7.17-7.11 (m, 2H), 6.96-6.92 (m, 1H), 5.51 (s, 2H), 5.14 (s, 2H), f 4.22 (s, 1H), 3.74 (s, 3H), 3.21-3,05 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 27 H 25 Cl2F2NO5 + Calculated 527.1136, found 527.1178.

[0083] Example 12: Compound LBS-12

[0084]

[0085] Using 2-hydroxy-5-methoxybenzaldehyde and 3-bromobenzyl bromide as starting materials, respectively, LBS-12, (S)-2-amino-3-(4-((2-((3-bromobenzyl)oxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a white solid using the same preparation method as LBS-1. 1H NMR (300 MHz, DMSO-d6): δ = 8.47 (br, 2H), 7.65 (s, 1H), 7.53 (d, J = 9 Hz, 1H), 7.54-7.31 (m, 4H), 7.14 (d, J = 3 Hz, 1H), 7.07 (d, J = 9 Hz, 1H), 6.96-6.92 (m, 1H), 5.09 (s, 2H), 5.05 (s, 2H), 4.21 (t, J = 7.5 Hz, 1H), 3.22-3.05 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 24 H 23 BrCl2NO5 + Calculated 554.0132, found 556.0124.

[0086] Example 13: Compound LBS-13

[0087]

[0088] LBS-13, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-2-((3-(pyridin-3- yl)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared using the same preparation method as LBS-1, with 2-hydroxy-5-methoxybenzaldehyde and 3-(3- (bromomethyl)phenyl)pyridine as starting materials, respectively. 1 H NMR (300 MHz, DMSO-d6): δ = 9.22 (d, J = 3 Hz, 1H), 8.87 (d, J = 6 Hz, 1H), 8.75 (d, J = 9 Hz, 1H), 8.55 (br, 2H), 8.05-8.01 (m, 1H), 7.98 (s, 1H), 7.59 (d, J = 6 Hz, 2H), 7.42 (s, 2H), 7.15-7.12 (m, 2H), 6.97-6.93 (m, 1H), 5.18 (s, 2H), 5.07 (s, 2H), 4.23 (s, 1H), 3.74 (s, 3H), 3.22-3.05 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 29 H 27 Cl2N2O5 + Calculated 553.1292, found 553.1309.

[0089] Example 14: Compound LBS-14

[0090]

[0091] Using 2-hydroxy-5-methoxybenzaldehyde and 5-(3-(bromomethyl)phenyl)pyrimidine as starting materials, respectively, LBS-14, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-2-((3-(pyrimidin-5-yl)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared by the same method as LBS-1, white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 9.22 (s, 1H), 9.15 (s, 2H), 8.52 (br, 2H), 7.90 (s, 1H), 7.80-7.77 (m, 1H), 7.56-7.54 (m, 2H), 7.41 (s, 2H), 7.15-7.11 (m, 2H), 6.96-6.92 (m, 1H), 5.17 (s, 2H), 5.06 (s, 2H), 4.23 (s, 1H), 3.74 (s, 3H), 3.21-3.04 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 28 H 26 Cl2N3O5 + Calculated 554.1245, found 554.1431.

[0092] Example 15: Compound LBS-15

[0093]

[0094] Using 2-hydroxy-5-methoxybenzaldehyde and (3-bromoprop-1-yn-1-yl)benzene as starting materials, respectively, LBS-15, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-2-((3-phenylprop-2-yn-1-yl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared by the same method as LBS-1, brown solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.54 (br, 2H), 7.47 (s, 2H), 7.44-7.40 (m, 5H), 7.17-7.13 (m, 2H), 6.98-6.94 (m, 1H), 5.04 (s, 2H), 4.99 (s, 2H), 4.24 (t, J = 6 Hz, 1H), 3.74 (s, 3H), 3.24-3.07 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 26 H 24 Cl2NO5 + Calculated 500.1027, found 500.1011.

[0095] Example 16: Compound LBS-16

[0096]

[0097] Using the same preparation method as LBS-1 with 2-hydroxy-5-methoxybenzaldehyde and (3-bromoprop-1-yn-1-yl)pyridine as starting materials, respectively, LBS-16, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-2-((3-(pyridin-4-yl)prop-2-yn-1-yl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared as a brown solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.83 (d, J = 6 Hz, 2H), 8.59 (br, 2H), 7.80 (d, J = 6 Hz, 2H), 7.49 (s, 2H), 7.20-7.15 (m, 2H), 7.00-6.96 (m, 1H), 5.13 (s, 2H), 5.06 (s, 2H), 4.24 (s, 1H), 3.76 (s, 3H), 3.25-3.10 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 23 Cl2N2O5 + Calculated 501.0979, found 501.0966.

[0098] Example 17: Compound LBS-17

[0099]

[0100] Using the same preparation method as LBS-1 with 2-hydroxy-5-methoxybenzaldehyde and 1-(3-bromoprop-1-yn-1-yl)-4-tert-butylbenzene as starting materials, respectively, LBS-17, (S)-2-amino-3-(4-((2-((3-(4-(tert-butyl)phenyl)prop-2-yn-1-yl)oxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a brown solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.84 (d, J = 6 Hz, 2H), 8.55 (br, 2H), 7.81 (d, J = 6 Hz, 2H), 7.47 (s, 2H), 7.21-7.16 (m, 2H), 7.03-6.98 (m, 1H), 5.14 (s, 2H), 5.06 (s, 2H), 4.24 (s, 1H), 3.76 (s, 3H), 3.26-3.10 (m, 2H), 1.4 (s, 9H) ppm. HRMS (ESI): m / z (M+H) + .C30 H 32 Cl2NO5 + Calculated 556.1653, found 556.1644.

[0101] Example 18: Compound LBS-18

[0102]

[0103] Using the same preparation method as LBS-1, with 2-hydroxy-5-methoxybenzaldehyde and 3-(3-bromoprop-1-yn-1-yl)benzonitrile as starting materials respectively, LBS-18, (S)-2-amino-3-(3,5-dichloro-4-((2-((3-(3-cyanophenyl)prop-2-yn-1-yl)oxy)-5-methoxybenzyl)oxy)phenyl)propanoic acid, was prepared as a gray solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.55 (br, 2H), 7.93-7.88 (m, 2H), 7.77 (d, J = 9 Hz, 1H), 7.63 (t, J = 7.5 Hz, 1H), 7.48 (s, 2H), 7.20-7.14 (m, 2H), 7.00-6.96 (m, 1H), 5.05 (s, 2H), 5.04 (s, 2H), 4.24 (t, J = 7.5 Hz, 1H), 3.76 (s, 3H), 3.25-3.08 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 27 H 23 Cl2N2O5 + Calculated 525.0979, found 525.0890.

[0104] Example 19: Compound LBS-19

[0105]

[0106] Using the same preparation method as LBS-1, with 2-hydroxy-5-methoxybenzaldehyde and 1-benzyl-4-(bromomethyl)-1H-1,2,3-triazole as starting materials respectively, LBS-19, (S)-2-amino-3-(4-((2-((1-benzyl-1H-1,2,3-triazol-4-yl)methoxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a yellow solid. 1HNMR (300 MHz, DMSO-d6): δ = 8.21 (br, 1H), 7.36-7.29 (m, 8H), 7.16-7.11 (m, 2H), 6.90 (d, J = 9 Hz, 1H), 5.61 (s, 2H), 5.10 (s, 2H), 4.91 (s, 2H), 3.73 (s, 3H), 3.42 (s, 1H), 3.05 (s, 1H), 2.86 (s, 1H) ppm. HRMS (ESI): m / z (M+H) + .C 27 H 27 Cl2N4O5 + Calculated 557.1354, found 557.1445.

[0107] Example 20: Compound LBS-20

[0108]

[0109] Using 2-hydroxy-5-tert-butylbenzaldehyde and 4-fluorobenzyl bromide as starting materials, respectively, LBS-20, (S)-2-amino-3-(4-((5-(tert-butyl)-2-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared by the same method as LBS-1, as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.55 (br, 2H), 7.52-7.49 (m, 2H), 7.30 (s, 1H), 7.18-7.14 (m, 5H), 6.78 (d, J = 6 Hz, 1H), 5.51 (s, 2H), 5.23 (s, 2H), 4.23 (t, J = 7.5 Hz, 1H), 3.71 (s, 3H), 3.26-3.08 (m, 2H), 1.31 (s, 9H) ppm. HRMS (ESI): m / z (M+H) + .C 27 H 29 Cl2FNO4 + Calculated 520.1453, found 520.1399.

[0110] Example 21: Compound LBS-21

[0111]

[0112] Using 2-hydroxy-5-ethynylbenzaldehyde and 2-(bromomethyl)naphthalene as starting materials, respectively, LBS-21, (S)-2-amino-3-(3,5-dichloro-4-((5-ethynyl-2-(naphthalen-2- ylmethoxy)benzyl)oxy)phenyl)propanoic acid, was prepared by the same method as LBS-1, as a white solid. δ = 8.56 (br, 2H), 8.00 (d, J = 3 Hz, 1H), 7.84-7.73 (m, 3H), 7.54-7.44 (m, 3H), 7.41-7.36 (m, 2H), 7.16 (s, 2H), 6.94 (d, J = 6 Hz, 1H), 5.47 (s, 2H), 5.38 (s, 2H), 4.22 (t, J = 7.5 Hz, 1H), 3.24-3.06 (m, 2H), 3.12 (s, 1H) ppm. HRMS (ESI): m / z (M+H) 1 H NMR (300 MHz, DMSO-d6): δ = 8.56 (br, 2H), 8.00 (d, J = 3 Hz, 1H), 7.84-7.73 (m, 3H), 7.54-7.44 (m, 3H), 7.41-7.36 (m, 2H), 7.16 (s, 2H), 6.94 (d, J = 6 Hz, 1H), 5.47 (s, 2H), 5.38 (s, 2H), 4.22 (t, J = 7.5 Hz, 1H), 3.24-3.06 (m, 2H), 3.12 (s, 1H) ppm. HRMS (ESI): m / z (M+H) + .C 29 H 24 Cl2NO4 + Calculated 520.1077, found 520.1056.

[0113] Example 22: Compound LBS-22

[0114]

[0115] Using 2-hydroxy-6-methoxybenzaldehyde and 3-bromobenzyl bromide as starting materials, respectively, LBS-22, (S)-2-amino-3-(4-((2-((3-bromobenzyl)oxy)-6-methoxybenzyl)oxy)-3,5- dichlorophenyl)propanoic acid, was prepared by the same method as LBS-1, as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.56 (br, 2H), 8.00 (d, J = 3 Hz, 1H), 7.84-7.73 (m, 3H), 7.54-7.44 (m, 3H), 7.41-7.36 (m, 2H), 7.16 (s, 2H), 6.94 (d, J = 6 Hz, 1H), 5.47 (s, 2H), 5.38 (s, 2H), 4.22 (t, J = 7.5 Hz, 1H), 3.24-3.06 (m, 2H), 3.12 (s, 1H) ppm. HRMS (ESI): m / z (M+H) + .C 24 H 23 BrCl2NO5 + Calculated 554.0132, found 556.0110.

[0116] Example 23: Compound LBS-23

[0117]

[0118] Using the same preparation method as LBS-1, LBS-23, (2S)-2-amino-3-(4-((2-(bicyclo[3.3.3]undecan-3-ylmethoxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a white solid, using 2-hydroxy-5-methoxybenzaldehyde and 1-(bromomethyl)adamantane as starting materials, respectively. 1 H NMR (300 MHz, DMSO-d6): δ = 8.44 (br, 2H), 7.16 (s, 2H), 6.88-6.86 (m, 1H), 6.81-6.75 (m, 2H), 5.15 (s, 2H), 4.20 (t, J = 7.5 Hz, 1H), 4.02 (s, 2H), 3.66 (s, 3H), 3.22-3.10 (m, 2H), 1.70-1.32 (m, 19H) ppm. HRMS (ESI): m / z (M+H) + .C 29 H 38 Cl2NO5 + Calculated 550.2122, found 550.2098.

[0119] Example 24: Compound LBS-24

[0120]

[0121] Step one: The starting material, 5-methoxysalicylaldehyde (1.5 g, 10 mmol), was dispersed in 20 ml acetic acid, and 2 ml concentrated nitric acid was added dropwise slowly. After the dropwise addition was completed, the reaction was allowed to proceed at room temperature for 6 h. TLC monitoring showed that the reaction was complete, and a large amount of yellow solid precipitated. The filter cake obtained by suction filtration was washed with methanol to obtain 2-hydroxy-5-methoxy-3-nitrobenzaldehyde (yellow solid, 1.2 g, yield 60.9%). Without further purification, it was directly used in the next step. HRMS (ESI): m / z (M+H) + .C8H8NO5 + Calculated 198.0397, found 198.0401.

[0122] The experimental methods of steps two to seven were the same as those of the preparation of LBS-1, and finally LBS-24, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-3-nitro-2-((4- (trifluoromethoxy)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was obtained as a yellow solid (0.3 g) through step seven. 1H NMR (300 MHz, DMSO-d6): δ = 8.47 (br, 2H), 7.71 (s, 1H), 7.57-7.54 (m, 3H), 7.44-7.37 (m, 4H), 5.19 (s, 2H), 5.12 (s, 2H), 4.19 (t, J = 6 Hz, 1H), 3.91 (s, 3H), 3.21-3.04 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 22 Cl2F3N2O8 + Calculated 605.0700, found 605.0689.

[0123] Example 25: Compound LBS-25

[0124]

[0125] Step one: (S)-methyl 2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((5- methoxy-3-nitro-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)phenyl)propanoate (1 g, 1.4 mmol) was dispersed in 20 ml of ethanol and 4 ml of water, and ammonium chloride (0.38 g, 6.9 mmol) was added. Iron powder (0.38 g, 6.9 mmol) was added under vigorous stirring, and the reaction was heated to reflux for 4 h. TLC monitoring showed that the reaction was complete, and the mixture was filtered on a Buchner funnel with celite pad while hot. The resulting filtrate was added to saturated aqueous sodium bicarbonate solution to adjust the pH to 8-9, and dichloromethane was added, and the organic layer was separated. The aqueous layer was extracted with dichloromethane twice, and the organic layers were combined. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated. The resulting residue was purified by silica gel column chromatography (petroleum ether: ethyl acetate = 3: 1) to give (S)-methyl 3-(4-((3-amino-5-methoxy-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoate (brown foamy solid, 0.6 g, yield 62.2%). HRMS (ESI): m / z (M+H) + .C 31 H 34 Cl2F3N2O8 + Calculated 689.1639, found 689.1622.

[0126] Step two: (S)-3-(4-((3-amino-5-methoxy-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (0.5 g, 0.7 mmol) was dissolved in 10 ml of methanol, 2M aqueous solution of lithium hydroxide (0.7 ml, 1.4 mmol) was added slowly dropwise and the reaction was allowed to proceed at room temperature for 3 h. TLC monitoring showed that the reaction was complete, 2N dilute aqueous hydrochloric acid was added slowly to adjust the pH to 4-5, water and dichloromethane were added, and the organic phase was separated. The aqueous phase was extracted twice with dichloromethane, and the combined organic phase was washed with saturated brine, dried over anhydrous sodium sulfate and concentrated to give (S)-3-(4-((3-amino-5-methoxy-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (yellow-brown oil, 0.45 g, yield 91.4%). It was used directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 30 H 32 Cl2F3N2O8 + Calculated 675.1483, found 675.1477.

[0127] Step three: (S)-3-(4-((3-amino-5-methoxy-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (0.4 g, 5.9 mmol) was dispersed in 8 ml of ethyl acetate and cooled to 0-5 °C. 4M hydrogen chloride ethyl acetate solution (1.5 ml, 59 mmol) was added slowly dropwise, and the reaction was allowed to proceed at room temperature for 20 h. TLC monitoring showed that the reaction was complete, and yellow-brown solid was precipitated. The solid was filtered, washed with a small amount of ethyl acetate and dichloromethane for 2-3 times, and dried to give LBS-26, (S)-2-amino-3-(4-((3-amino-5-methoxy-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid (yellow-brown solid, 0.27 g, yield 67.5%). 1 H NMR (300 MHz, DMSO-d6): δ = 8.90 (br, 2H), 8.45 (br, 2H), 7.88 (s, 1H), 7.76-7.67 (m, 3H), 7.39-7.31 (m, 4H), 5.15 (s, 2H), 5.10 (s, 2H), 4.21 (t, J = 6 Hz, 1H), 3.89 (s, 3H), 3.22-3.03 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H24 Cl2F3N2O6 + Calculated 575.0959, found 575.0885.

[0128] Example 26: Compound LBS-26

[0129]

[0130] Intermediate IV-1 was prepared using the same method as for the synthesis of intermediate I-9, starting from 2-hydroxy-5-nitrobenzaldehyde and 2-(bromomethyl)naphthalene, (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((2-(naphthalen-2-ylmethoxy)-5-nitrobenzyl)oxy)phenyl)propanoate.

[0131] Step one: (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((2-(naphthalen-2-ylmethoxy)-5-nitrobenzyl)oxy)phenyl)propanoate (1 g, 1.5 mmol) was dispersed in 20 ml of ethanol and 4 ml of water, and stirring was started after the addition of ammonium chloride (0.41 g, 7.6 mmol). Iron powder (0.42 g, 7.6 mmol) was added under vigorous stirring, and the reaction was allowed to proceed at reflux for 4 h. After the completion of the reaction was monitored by TLC, the mixture was filtered hot on a Buchner funnel over celite. The filtrate was added to saturated aqueous sodium bicarbonate solution to adjust the pH to 8-9, and dichloromethane was added. The organic layer was separated, and the aqueous layer was extracted twice with dichloromethane. The combined organic layers were washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by column chromatography on silica gel (petroleum ether: ethyl acetate = 1:1) to give (S)-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoate (brown foamy solid, 0.8 g, 85% yield). HRMS (ESI): m / z (M+H) + .C 33 H 35 Cl2N2O6 + Calculated 625.1867, found 625.1855.

[0132] Step two: (S)-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (0.7 g, 1.1 mmol) was dissolved in 10 ml of tetrahydrofuran, 2M sodium hydroxide aqueous solution (1.1 ml, 2.2 mmol) was added dropwise slowly. After the addition was completed, the reaction was stirred at room temperature for 3 h. TLC monitoring showed that the reaction was completed, 1N hydrochloric acid aqueous solution was added to adjust the pH to 3-4, dichloromethane was added, and the organic layer was separated. The aqueous phase was extracted with dichloromethane twice, washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated in vacuo to give (S)-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5-dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (yellowish oil, 0.65 g, yield 95.6%). It was used directly in the next step without purification. HRMS (ESI): m / z (M+H) + .C 32 H 33 Cl2N2O6 + Calculated value is 611.1711, measured value 611.1709.

[0133] Step three: (S)-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (0.61 g, 1 mmol) was dispersed in 10 ml of 1,4-dioxane, and the temperature was lowered to 0-5°C. 4M hydrogen chloride solution in 1,4-dioxane (2.5 ml, 10 mmol) was added dropwise slowly. After the addition was completed, the reaction was stirred at room temperature for 12 h. TLC monitoring showed that the reaction was completed, and the solvent was removed by vacuum concentration. Dichloromethane and isopropyl ether were added to make a slurry, and LBS-26, (S)-2-amino-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid was obtained by suction filtration (yellowish brown solid, 0.4 g, yield 68.9%). 1 H NMR (300 MHz, DMSO-d6): δ = 8.54 (br, 2H), 7.99-7.89 (m, 4H), 7.66 (d, J = 3 Hz, 1H), 7.60-7.52 (m, 3H), 7.45-7.40 (m, 3H), 7.32 (d, J = 9 Hz, 1H), 5.34 (s, 2H), 5.09 (s, 2H), 4.24 (t, J = 6 Hz, 1H), 3.22-3.04 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 27 H 25 Cl2N2O4 +Calculated 511.1186, found 511.1171.

[0134] Example 27: Compound LBS-27

[0135]

[0136] Using the same method as for the preparation of LBS-26, starting from 2-hydroxy-5- nitrobenzaldehyde and 4-trifluoromethoxybenzyl bromide, LBS-27, (S)-2-amino-3-(4-((5- amino-2-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a brown solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.56 (br, 2H), 7.55 (d, J = 3 Hz, 1H), 7.59 (d, J = 6 Hz, 2H), 7.47 (s, 2H), 7.43-7.39 (m, 3H), 7.25 (d, J = 9 Hz, 1H), 5.21 (s, 2H), 5.06 (s, 2H), 4.26 (t, J = 6 Hz, 1H), 3.26-3.08 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + . 24 H 22 Cl2F3N2O5 + Calculated 545.0853, found 545.0908.

[0137] Example 28: Compound LBS-28

[0138]

[0139] Using the same method as for the preparation of LBS-26, starting from 2-hydroxy-5- nitrobenzaldehyde and 4-fluorobenzyl bromide, LBS-28, (S)-2-amino-3-(4-((5-amino-2-((4- fluorobenzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a red- brown solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.58 (br, 2H), 7.65 (d, J = 3 Hz, 1H), 7.53-7.41 (m, 5H), 7.28-7.19 (m, 3H), 5.16 (s, 2H), 5.03 (s, 2H), 4.26 (t, J = 6 Hz, 1H), 3.26-3.09 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + . 23 H 22 Cl2FN2O4 +Calculated 479.0936, found 479.0937.

[0140] Example 29: Compound LBS-29

[0141]

[0142] Step one: Dissolve (S)-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (0.5 g, 0.8 mmol) in 5 ml dichloromethane, cool down to 0-5 °C. Slowly drop in acetic anhydride (0.16 g, 0.96 mmol) under cooling. After drop completion, raise to room temperature and react for 1 h. TLC monitor reaction complete, add water and dichloromethane. Separate organic phase, water phase extract with dichloromethane twice. Combine organic phase, wash with saturated brine, dry over anhydrous sodium sulfate, then concentrate the obtained and purify with silica gel column (petroleum ether: ethyl acetate = 2: 1) to get (S)-3-(4-((5-acetylamino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (white solid, 0.45 g, yield 84.9%). HRMS (ESI): m / z (M+H) + .C 35 H 37 Cl2N2O7 + Calculated 667.1973, found 667.1966.

[0143] Step two: Dissolve (S)-3-(4-((5-acetylamino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (0.4 g, 0.59 mmol) in 5 ml tetrahydrofuran, slowly drop in 2M sodium hydroxide aqueous solution (0.6 ml, 1.18 mmol). After drop completion, react at room temperature for 3 h. TLC monitor reaction complete, add 1N hydrochloric acid aqueous solution to adjust pH to 2-3, add dichloromethane, separate organic layer. Water phase extract with dichloromethane twice, wash with saturated brine, dry over anhydrous sodium sulfate, then concentrate in vacuum to get (S)-3-(4-((5-acetylamino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (white solid, 0.65 g, yield 95.6%). Use directly in next step reaction without purification. HRMS (ESI): m / z (M+H) + .C 34 H 35 Cl2N2O7 + Calculated 653.1816, found 653.1811.

[0144] Step 3: (S)-3-(4-((5-acetylamino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (0.5 g, 0.76 mmol) was dissolved in 5 ml of 1,4-dioxane and cooled to 0-5 °C. 4M Hydrogen chloride in 1,4-dioxane (1.8 ml, 7.6 mmol) was added slowly dropwise. After the addition was complete, the reaction mixture was allowed to warm to room temperature and stirred for 12 h. The reaction was monitored by TLC and the solvent was removed by vacuum concentration. Dichloromethane and ethyl acetate were added and the mixture was filtered to give LBS-29, (S)-3-(4-((5-acetylamino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-amino propanoic acid (white solid, 0.31 g, 70.4% yield). 1 H NMR (300 MHz, DMSO-d6): δ = 9.97 (s, 1H), 8.43 (br, 2H), 7.97-7.87 (m, 4H), 7.79 (d, J = 3 Hz, 1H), 7.63-7.50 (m, 4H), 7.41 (s, 2H), 7.14 (d, J = 9 Hz, 1H), 5.27 (s, 2H), 5.03 (s, 2H), 4.24 (s, 1H), 3.18-2.99 (m, 2H), 2.03 (s, 3H) ppm. HRMS (ESI): m / z (M+H) + .C 29 H 27 Cl2N2O5 + Calculated 553.1292, found 553.1283.

[0145] Example 30: Compound LBS-30

[0146]

[0147] Using the same method as for the preparation of LBS-29, starting from 2-hydroxy-5- nitrobenzaldehyde and 4-fluorobenzyl bromide, LBS-30, (S)-3-(4-((5-acetylamino-2- ((4-fluorobenzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)-2-amino propanoic acid, was prepared as a white solid. 1H NMR (300 MHz, DMSO-d6): δ = 10.02 (s, 1H), 8.51 (br, 2H), 7.77 (d, J = 3 Hz, 1H), 7.65-7.61 (m, 1H), 7.52-7.45 (m, 4H), 7.22 (t, J = 9 Hz, 2H), 7.08 (d, J = 9 Hz, 1H), 5.08 (s, 2H), 4.99 (s, 2H), 4.26 (s, 1H), 3.24-3.06 (m, 2H), 2.04 (s, 3H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 24 Cl2FN2O5 + Calculated 521.1041, found 521.1028.

[0148] Example 31: Compound LBS-31

[0149]

[0150] Using the same method as for the preparation of LBS-29, with acetic anhydride replaced by methanesulfonic anhydride, starting from intermediate IV-2, (S)-2-amino-3-(3,5-dichloro-4-((5-(methanesulfonamido)-2-(naphthalen-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid, LBS-31, was prepared as a yellow solid. 1 H NMR (300 MHz, DMSO-d6): δ = 10.02 (s, 1H), 8.51 (br, 2H), 7.77 (d, J = 3 Hz, 1H), 7.65-7.61 (m, 1H), 7.52-7.45 (m, 4H), 7.22 (t, J = 9 Hz, 2H), 7.08 (d, J = 9 Hz, 1H), 5.08 (s, 2H), 4.99 (s, 2H), 4.26 (s, 1H), 3.24-3.06 (m, 2H), 2.04 (s, 3H) ppm. HRMS (ESI): m / z (M+H) + .C 28 H 27 Cl2N2O6S + Calculated 589.0962, found 589.1000.

[0151] Example 32: Compound LBS-32

[0152]

[0153] Step one: (S)-3-(4-((5-amino-2-(naphthalen-2-ylmethoxy)benzyl)oxy)-3,5- dichlorophenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid methyl ester (1 g, 1.6 mmol) was dissolved in 10 ml of N,N-dimethylformamide and warmed to 80 °C. Then the solution of formic acid (0.5 ml) and 37% formaldehyde solution (0.5 ml) in 5 ml of N,N-dimethylformamide was added dropwise. After the addition was completed, the reaction was allowed to proceed for 2 h. TLC monitoring showed that the reaction was complete. The pH was adjusted to 7-9 by adding saturated aqueous sodium bicarbonate solution. Ethyl acetate was added and the organic phase was separated. The aqueous phase was extracted twice with ethyl acetate. The combined organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by column chromatography on silica gel (petroleum ether: ethyl acetate = 4: 1) to give (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((5-(dimethylamino)-2- (naphthalen-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid methyl ester (off-white solid, 0.8 g, 80.5% yield). HRMS (ESI): m / z (M+H) + .C 35 H 39 Cl2N2O6 + Calculated 653.2180, found 653.2183.

[0154] Step two: (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((5-(dimethylamino)-2- (naphthalen-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid methyl ester (0.4 g, 0.6 mmol) was dissolved in 5 ml of methanol, and 2M aqueous sodium hydroxide solution (0.6 ml, 1.2 mmol) was added dropwise. After the addition was completed, the reaction was allowed to proceed for 4 h at room temperature. After TLC monitoring showed that the reaction was complete, the pH was adjusted to 3-4 by adding 1N aqueous hydrochloric acid solution. Dichloromethane was added and the organic layer was separated. The aqueous phase was extracted twice with dichloromethane. The combined organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated in vacuo to give (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((5-(dimethylamino)-2- (naphthalen-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid (white solid, 0.38 g, 97.5% yield). HRMS (ESI): m / z (M+H) + .C 34 H 37 Cl2N2O6 + Calculated 639.2024, found 639.2018.

[0155] Step three: (S)-2-((tert-butoxycarbonyl)amino)-3-(3,5-dichloro-4-((5-(dimethylamino)- 2-(naphthalen-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid (0.35 g, 0.5 mmol) was dispersed in 5 ml of 1,4-dioxane, and cooled to 0-5 °C. 4M hydrogen chloride solution in 1,4-dioxane (1.25 ml, 5 mmol) was added slowly dropwise, and the reaction was allowed to warm to room temperature for 15 h. TLC monitoring showed that the reaction was complete, and the solvent was removed by vacuum evaporation to give a colorless oil. Isopropyl ether was added to the slurry, and the product was filtered to give LBS-32, (S)-2-amino-3-(3,5-dichloro-4-((5-(dimethylamino)-2- (naphthalen-2-ylmethoxy)benzyl)oxy)phenyl)propanoic acid (pale yellow solid, 0.22 g, 75.9% yield). 1 H NMR (300 MHz, DMSO-d6): δ = 8.52 (br, 2H), 8.00-7.79 (m, 6H), 7.59-7.54 (m, 3H), 7.43 (s, 2H), 7.37 (d, J = 9 Hz, 1H), 5.37 (s, 2H), 5.11 (s, 2H), 4.24 (s, 1H), 3.20-3.02 (m, 8H), ppm. HRMS (ESI): m / z (M+H) + .C 29 H 29 Cl2N2O4 + Calculated 539.1499, found 539.1541.

[0156] Example 33: Compound LBS-33

[0157]

[0158] LBS-33 was prepared using the same method as LBS-32, with 2-hydroxy-5- nitrobenzaldehyde and 4-trifluoromethoxybromobenzene as starting materials, and was obtained as a pale yellow solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.52 (br, 2H), 8.00-7.79 (m, 6H), 7.59-7.54 (m, 3H), 7.43 (s, 2H), 7.37 (d, J = 9 Hz, 1H), 5.37 (s, 2H), 5.11 (s, 2H), 4.24 (s, 1H), 3.20-3.02 (m, 8H), ppm. HRMS (ESI): m / z (M+H) + .C 26 H 26 Cl2F3N2O5 +Calculated 573.1166, found 573.1282.

[0159] Example 34: Compound LBS-34

[0160]

[0161] Step one: 5-methoxy-2-nitro-benzaldehyde (1 g, 5.5 mmol) was dissolved in 10 ml of methanol, and cooled to 0-5 °C. Sodium borohydride (0.23 g, 6.1 mmol) was added slowly at 0-5 °C. A large amount of gas was released during the dropwise addition. After the dropwise addition was completed, the reaction was allowed to warm to room temperature and stirred for 0.5 h. TLC monitoring showed that the reaction was complete. Saturated sodium bicarbonate solution was added to adjust the pH of the mixture to 8-9. Dichloromethane was added and the organic phase was separated. The aqueous phase was extracted twice with dichloromethane. The combined organic phase was washed with saturated brine, dried over anhydrous sodium sulfate for 2 h. The filtrate was concentrated under vacuum to give (5-methoxy-2-nitrophenyl)methanol (yellow solid, 1 g, 99.1% yield). No purification was needed, and the product was used directly in the next step.

[0162] Step two: (5-methoxy-2-nitrophenyl)methanol (1 g, 5.5 mmol) was dissolved in 10 ml of methanol, and SnCl2(5.2 g, 27.6 mmol) was added. The reaction was brought to reflux and heated for 4 h. TLC monitoring showed that the reaction was complete. The reaction was cooled to room temperature. The reaction was slowly poured into a saturated aqueous sodium carbonate solution (30 ml), and dichloromethane was added. The mixture was then filtered through celite. The filter cake was washed with dichloromethane several times. The filtrate was collected and the organic phase was separated. The aqueous phase was extracted twice with dichloromethane. The combined organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under vacuum. Purification was performed by silica gel column chromatography (dichloromethane:methanol = 30:1) to give (2-amino-5-methoxyphenyl)methanol (brown foamy solid, 0.6 g, 71.3% yield).

[0163] Step three: (2-amino-5-methoxyphenyl)methanol (0.5 g, 3.2 mmol) and 4- (bromomethyl)-l-fluoro-2-(trifluoromethyl)benzene (0.42 g, 1.6 mmol) were added to 10 ml of N,N-dimethylformamide. Potassium carbonate (0.44 g, 3.2 mmol) was added, and the reaction was stirred at room temperature for 2 h. TLC monitoring showed that the reaction was complete. Water and ethyl acetate were added, and the organic phase was separated. The aqueous phase was extracted twice with ethyl acetate. The combined organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under vacuum. Purification was performed by silica gel column chromatography (petroleum ether: ethyl acetate = 1:1) to give (2-((4-fluoro-3-(trifluoromethyl)benzyl)amino)-5-methoxyphenyl)methanol (brown solid, 0.3 g, 57% yield).

[0164] The synthetic procedure of step four to step seven is the same as the preparation of LBS-1. Finally, LBS-34, (S)-2-amino-3-(3,5-dichloro-4-((2-((4-fluoro-3-(trifluoromethyl)benzyl)amino)-5-methoxybenzyl)oxy)phenyl)propanoic acid, was obtained via step seven as a brown solid, 0.05 g. 1 H NMR (300 MHz, DMSO-d6): δ = 8.52 (br, 2H), 7.81-7.89 (m, 2H), 7.54-7.49 (m, 1H), 7.39 (s, 2H), 7.14-7.09 (m, 2H), 6.98-6.84 (m, 1H), 5.16 (s, 2H), 4.41 (s, 2H), 4.24 (t, J = 4.5 Hz, 1H), 3.76 (s, 3H), 3.23-3.05 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 23 Cl2F4N2O4 + Calculated 561.0966, found 561.0896.

[0165] The compounds of Examples 35-37 were prepared according to the procedure and route described in Reference Example 34.

[0166] Example 35: Compound LBS-35

[0167]

[0168] Using 5-methoxy-2-nitro-benzaldehyde and 4-(trifluoromethoxy)benzyl bromide as the corresponding starting materials, LBS-35, (S)-2-amino-3-(3,5-dichloro-4-((5-methoxy-2-((4-(trifluoromethoxy)benzyl)amino)benzyl)oxy)phenyl)propanoic acid, was prepared according to the same procedure as LBS-34 as a brown solid. 1H NMR (300 MHz, DMSO-d6): δ = 8.66 (br, 2H), 7.55-7.50 (d, J = 9 Hz, 2H), 7.47 (s, 1H), 7.38 (d, J = 9 Hz, 2H), 7.16 (d, J = 3 Hz, 1H), 7.07 (d, J = 9 Hz, 1H), 6.96-6.90 (m, 1H), 5.15 (s, 2H), 4.46 (s, 2H), 4.25 (t, J = 4.5 Hz, 1H), 3.74 (s, 1H), 3.25-3.07 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 24Cl2F3N2O5 + Calculated 559.1009, found 559.1000.

[0169] Example 36: Compound LBS-36

[0170]

[0171] Using the same method as for the preparation of LBS-34, starting from 5- trifluoromethyl-2-nitro-benzaldehyde and 3-(bromomethyl)-1,1'-biphenyl, LBS-36, (S)-3-(4-((2-(([1,1'-biphenyl]-3-ylmethyl)amino)-5-(trifluoromethyl)benzyl)oxy)-3,5- dichlorophenyl)-2-aminopropanoic acid, was prepared as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.47 (br, 2H), 7.78 (s, 1H), 7.66-7.60 (m, 3H), 7.55-7.44 (m, 7H), 7.16-7.11 (m, 2H), 6.98-6.97 (m, 1H), 5.18 (s, 2H), 4.56 (s, 2H), 4.20 (t, J = 6 Hz, 1H), 3.22-3.06 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + . 30 H 26 Cl2F3N2O3 + Calculated 589.1286, found 589.1299.

[0172] Example 37: Compound LBS-37

[0173]

[0174] Using the same method as for the preparation of LBS-34, starting from 5- trifluoromethyl-2-nitro-benzaldehyde and 3-(bromomethyl)-1,1'-biphenyl, LBS-36, (S)-3-(4-((2-(([1,1'-biphenyl]-3-ylmethyl)amino)-5-(trifluoromethyl)benzyl)oxy)-3,5- dichlorophenyl)-2-aminopropanoic acid, was prepared as a white solid. 1H NMR (300 MHz, DMSO-d6): δ = 8.49 (br, 2H), 7.47 (s, 2H), 7.48-7.41 (m, 5H), 7.18-7.13 (m, 2H), 6.97-6.92 (m, 1H), 5.14 (s, 2H), 4.67 (s, 2H), 4.24 (t, J = 4.5 Hz, 1H), 3.64 (s, 3H), 3.26-3.08 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 26 H 25 Cl2N2O4 + Calculated 499.1186, found 499.1177.

[0175] Example 38: Compound LBS-38

[0176]

[0177] Using the same preparation method as LBS-1, with 3-hydroxy-5-methoxybenzaldehyde and 4-trifluoromethoxybenzyl bromide as starting materials respectively, LBS-38, (S)-2-amino-3-(3,5-dichloro-4-((3-methoxy-5-((4-(trifluoromethoxy)benzyl)oxy)benzyl)oxy)phenyl)propanoic acid, was prepared as a white solid. 1 H NMR (300 MHz, DMSO-d6): δ = 8.45 (br, 2H), 7.61 (d, J = 9 Hz, 2H), 7.49 (s, 2H), 7.42 (d, J = 6 Hz, 2H), 6.80 (s, 1H), 6.72 (s, 1H), 6.63 (t, J = 6 Hz, 1H), 5.18 (s, 2H), 4.94 (s, 2H), 4.29 (s, 1H), 3.78 (s, 3H), 3.24-3.06 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 25 H 23 Cl2F3NO6 + Calculated 560.0850, found 560.0977.

[0178] Example 39: Compound LBS-39

[0179]

[0180] Using 3-hydroxy-5-methoxybenzaldehyde and 2-(bromomethyl)-1,1'-biphenyl as starting materials, respectively, LBS-39, (S)-3-(4-((3-([1,1'-biphenyl]-2-ylmethoxy)-5-methoxybenzyl)oxy)-3,5-dichlorophenyl)-2-aminopropanoic acid, was prepared as a white solid using the same method as LBS-1. 1 H NMR (300 MHz, DMSO-d6): δ = 8.59 (br, 2H), 7.68-7.62 (m, 3H), 7.58 (s, 1H), 7.51-7.37 (m, 7H), 7.16-7.10 (m, 2H), 6.88-6.84 (m, 1H), 5.17 (s, 2H), 5.01 (s, 2H), 4.22 (t, J = 6 Hz, 1H), 3.64 (s, 3H), 3.22-3.01 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 30 H 28 Cl2NO5 + Calculated 552.1340, found 552.1329.

[0181] Example 40: Compound LBS-40

[0182]

[0183] Using 3-hydroxy-5-nitrobenzaldehyde and 4-fluorobenzyl bromide as starting materials, LBS-40, (S)-2-amino-3-(4-((3-amino-5-((4-fluorobenzyl)oxy)benzyl)oxy)-3,5-dichlorophenyl)propanoic acid, was prepared as a brown solid using the same method as LBS-26. 1 H NMR (300 MHz, DMSO-d6): δ = 8.58 (br, 2H), 7.65 (d, J = 3 Hz, 2H), 7.18-7.15 (m, 4H), 6.48 (s, 1H), 6.43 (s, 1H), 6.18 (s, 1H), 5.16 (s, 2H), 5.11 (s, 2H), 4.22 (t, J = 4.5 Hz, 1H), 3.22-3.06 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 23 H 22 Cl2FN2O4 + Calculated 479.0936, found 479.0892.

[0184] Example 41: Compound LBS-41

[0185]

[0186] Using 5-methoxy-3-nitro-benzaldehyde and (3-bromoprop-1-yn-1-yl)benzene as the corresponding starting materials, LBS-41, (S)-2-amino-3-(3,5-dichloro-4-((3-methoxy-5-((3-phenylprop-2-yn-1-yl)amino)benzyl)oxy)phenyl)propanoic acid, was prepared as a light yellow solid by the same method as LBS-34. 1 H NMR (300 MHz, DMSO-d6): δ = 8.46 (br, 2H), 7.57 (s, 1H), 7.51-7.47 (m, 3H), 7.19-7.13 (m, 5H), 6.88-6.75 (m, 1H), 5.18 (s, 2H), 4.39 (s, 2H), 4.20 (t, J = 6 Hz, 1H), 3.71 (s, 3H), 3.22-3.06 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 26 H 25 Cl2N2O4 + Calculated 499.1186, found 499.1169.

[0187] Example 42: Compound LBS-42

[0188]

[0189] Using 5-methoxy-3-nitro-benzaldehyde and (3-bromoprop-1-yn-1-yl)benzene as the corresponding starting materials, LBS-41, (S)-2-amino-3-(3,5-dichloro-4-((3-methoxy-5-((3-phenylprop-2-yn-1-yl)amino)benzyl)oxy)phenyl)propanoic acid, was prepared as a light yellow solid by the same method as LBS-34. 1 H NMR (300 MHz, DMSO-d6): δ = 8.46 (br, 2H), 7.57 (s, 1H), 7.51-7.47 (m, 3H), 7.19-7.13 (m, 5H), 6.88-6.75 (m, 1H), 5.18 (s, 2H), 4.39 (s, 2H), 4.20 (t, J = 6 Hz, 1H), 3.71 (s, 3H), 3.22-3.06 (m, 2H) ppm. HRMS (ESI): m / z (M+H) + .C 24 H 21 Cl2F4N2O3 + Calculated 531.0860, found 531.0790.

[0190] Biological activity test

[0191] LAT1 inhibitory activity assay:

[0192] Leucine, as a transport substrate with high affinity for LAT1, can be used to evaluate the inhibitory activity of compounds against LAT1 through leucine transport experiments.

[0193] 1. Experimental Method:

[0194] (1) Cell Culture

[0195] (2) Plate preparation: 40,000 wells of 24-well plate, 37°C, 5% CO2 culture for 24 h;

[0196] (3) When the confluence of HEK-293T cells reaches 60%, the SLC7A5 plasmid is transfected into the cells using JetPrime transfection reagent according to the instructions. After 48 hours of transfection, the 24-well plate is removed from the incubator.

[0197] (4) Discard the culture medium in the plate, wash three times with a Na+-free Hank's solution preheated to 37°C (125mM choline chloride, 25mM Hpes, 4.8mM KCl, 1.2mM KH2PO4, 1.2mM MgSO4·7H2O, 1.3mM CaCl2, 5.6mM D-glucose, pH=7.4), and incubate at 37°C for 7 min;

[0198] (5) Add 250 μL of inhibitor solutions of different concentrations (10 mM compound stock solution containing 5 μM). 2 H-Leu's Na+-free Hank's solution was diluted to 20 μM and 2 μM and then in a water bath at 37°C for 15 minutes.

[0199] (6) After incubation, aspirate the liquid and wash the cells three times with cold, Na+-free Hank's solution. Add 200 μL of ultrapure water. Perform three freeze-thaw cycles at -80°C to scrape the cells into a 1.5 mL EP tube. After sonicating for 15 min, take 30 μL of the disrupted cell sample and add it to a 1.5 mL EP tube. Add 30 μL of diluent and 60 μL of internal standard solution, vortex for 2 min, and centrifuge at 12000 rpm for 10 min at 4°C. Transfer 60 μL of the supernatant to a vial for LC-MS / MS analysis. 2 H-Leu content.

[0200] 2. Data Analysis

[0201] The formula for calculating %Inhibition in the leucine transport experiment is: %Inhibition = [1 - (A_sample / A_max)] where: A_sample represents the concentration of leucine in the administered sample. 2 H-Leu content, A_max represents the H-Leu content in the blank sample.2 H-Leu content, and graphpad was used to fit the IC values of each compound to LAT1 50

[0202] Table 1, IC values of each compound to LAT1 50

[0203]

[0204]

[0205] A <1uM; 1uM < B < 100uM; C > 100uM.

[0206] This experiment reflects the inhibition level of LAT1 by evaluating the degree of inhibition of the amount of leucine uptake by cells. As shown in Table 1, the compounds LBS-1 to LBS-42 of the present application exhibit significant inhibitory activity against LAT1. Among them, the IC 50 values of compounds LBS-3, LBS-5 to 11, LBS-13 to 18, LBS-21 to 23, LBS-26 to 27 to LAT1 all reached below 1uM, showing more significant affinity to LAT1, and having potential for the treatment of cancer or immune diseases.​​

Claims

1. An aromatic amino acid derivative as a LAT1 inhibitor, characterized in that, The derivatives include compounds as shown in structural formula (I), their stereoisomers, or their pharmaceutically acceptable salts: ； Among them, R 1 Selected from H, halogen, OH, NH2, CN, C1-C6 alkyl, C2-C6 alkynyl, or phenyl, wherein the OH, NH2, C1-C6 alkyl, C2-C6 alkynyl, or phenyl is R 1a Replace, R 1a Selected from F, CN, CH3, CF3, -COCH3, or -S(O)2CH3; R 2 R 3 Selected from H or CH3; R 4 Selected from H or Cl; R 5 Independently selected from H, halogens, OH, CN, CH3, C(CH3)3, , , or The OH, CN, CH3, , , or R 5a Replace, R 5a Selected from halogens, C1-C6 haloalkyl groups, or phenyl groups; L is selected from -O-L1- or -NH-L1-, and L1 is selected from CH2 or ; Ring A is selected from , , , , , or m is 1, n is 1 or 2, and p is 2.

2. The aromatic amino acid derivative according to claim 1, characterized in that, The derivatives include those of formula ( ) or formula ( I) The compound or its stereoisomer or its pharmaceutically acceptable salt: ； Among them, R 1 R 2 R 3 R 4 R 5 L or ring A as defined in claim 1.

3. A method for preparing the aromatic amino acid derivative as a LAT1 inhibitor according to claim 1, characterized in that, It is prepared by the following synthetic route: 。 4. A pharmaceutical composition, characterized in that, It comprises an aromatic amino acid derivative of formula (I) as shown in claim 1, or a stereoisomer thereof, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable excipient.

5. The use of the aromatic amino acid derivative of claim 1 in the preparation of a medicament for the prevention or treatment of LAT1-mediated diseases.

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