CN109776377B - Indoline compounds and preparation method and application thereof - Google Patents

Abstract

The invention belongs to the technical field of medicine, and discloses an indoline compound having the structure of general formula I, a preparation method and application thereof, wherein the substituents R ₁ , R ₂ , R ₃ , R ₄ and R ₅ have the properties given in the description. meaning. The indoline compounds and their stereoisomers, pharmaceutically acceptable salts or pharmaceutical compositions containing the compounds can be used to prepare and treat diseases related to PD-1/PD-L1 protein/protein interactions such as Drugs for various diseases such as cancer and viral infections.

Description

Indoline compounds and preparation method and application thereof

Technical field:

The invention belongs to the technical field of medicine, and relates to indoline compounds and a preparation method and application thereof, in particular to indoline compounds, their preparation methods and pharmaceutical compositions containing the compounds. The present invention also relates to the compounds and their stereoisomers and pharmaceutically acceptable salts in the preparation of medicines for treating diseases related to PD-1/PD-L1 signaling pathway, such as cancer, infectious diseases and autoimmune diseases the use of.

Background technique:

Immunotherapy is a hot field of tumor treatment in recent years, and was rated as the top ten scientific breakthroughs by "Science" in 2013. Programmed death 1 (PD-1) is a T cell surface receptor that when it binds to programmed death ligand 1 (PD-L1) produces a negative immunoregulatory signal, thereby inhibiting T cell activation , proliferation and the release of cytokines such as interleukin 2 (IL-2) and interferon gamma (IFN-γ) (Eur. J. Immunol., 2002, 32(3), 634-643.). A large number of studies have shown that the tumor microenvironment in the body can induce the up-regulation of PD-1 expression in infiltrating T cells, and at the same time, tumor cells highly express PD-L1, resulting in the continuous activation of PD-1/PD-L1-mediated signaling pathways, and tumor specificity. Sexual CD8+ T cell function is suppressed so that it cannot recognize or kill tumor cells, that is, tumor cells achieve immune escape. Therefore, targeted blocking of PD-1/PD-L1 protein/protein interaction can restore T cell function, allowing it to re-recognize and kill tumor cells.

Immunotherapy based on PD-1/PD-L1 has attracted much attention, and the PD-1/PD-L1 monoclonal antibodies that have been approved for marketing include Pembrolizumab of Merck, Nivolumab of Bristol-Myers Squibb, Avelumab of Merck, AstraZeneca Durvalumab, Roche's Atezolizumab, etc. The above monoclonal antibodies have shown significant efficacy in the treatment of various tumor types, and the approved indications include melanoma, non-small cell lung cancer, gastric cancer, urothelial cancer, etc. With the development of clinical research, monoclonal antibodies are expected to achieve breakthroughs in more indications.

Although monoclonal antibody drugs show advantages in clinical treatment, they also have obvious defects such as difficult preparation and purification, high production cost; easy to be decomposed by protease, short half-life; can not be taken orally, only by injection; the immunogen of monoclonal antibody Sex leads to serious toxic side effects. Compared with biological macromolecular drugs, the pharmacokinetic properties of small molecular compounds after chemical modification are controllable, and they also have greater space for exploration and optimization in terms of production technology and administration methods. Therefore, the development of small-molecule inhibitors targeting PD-1/PD-L1 protein/protein interactions is a feasible option for realizing immunotherapy.

At present, the development of small molecule PD-1/PD-L1 inhibitors is in the early stage. Curis’ PD-L1 inhibitor AC-170 is in clinical phase I, and the small molecule inhibitors of Bristol-Myers Squibb and Incyte are still in the preclinical research stage. Therefore, there is an urgent need to develop small-molecule PD-1/PD-L1 inhibitors with novel chemical structures.

The inventors designed and synthesized a series of new indoline compounds. The results of the activity study showed that these compounds can significantly inhibit the PD-1/PD-L1 protein/protein interaction.

Invention content:

The present invention provides the indoline compounds of general formula I and their stereoisomers and pharmaceutically acceptable salts,

in,

R ₁ is selected from unsubstituted or phenyl substituted with 1-3 R ₆ , or

R ₆ is independently selected from halogen, (C ₁ -C ₄ )alkyl, (C ₁ -C ₄ )alkoxy;

R ₂ and R ₃ are independently selected from hydrogen, halogen, hydroxyl, (C ₁ -C ₄ )alkyl, (C ₁ -C ₄ )alkoxy,

R ₉ is independently selected from cyano, mesyl, acetamido, carbamoyl;

R ₄ , R ₅ are independently selected from hydrogen, (C ₁ -C ₄ ) alkyl, (C ₃ -C ₈ ) cycloalkyl, hydroxy (C ₁ -C ₄ ) alkyl, amino (C ₁ -C ₄ ) ) alkyl, carbamoyl (C ₁ -C ₄ ) alkyl, aminosulfonyl (C ₁ -C ₄ ) alkyl, methanesulfonamido (C ₁ -C ₄ ) alkyl, carboxyl (C ₁ -C 4 ) alkyl ₄ ) alkyl, (C ₁ -C ₄ )alkoxycarbonyl (C ₁ -C ₄ ) alkyl, tetrahydropyran-4-yl; the (C ₁ -C ₄ ) alkyl, (C ₃ ) _-C8 )cycloalkyl, hydroxy( _C1 - _C4 )alkyl, amino( _C1 - _C4 )alkyl, carbamoyl( _{C1 - C4} )alkyl, aminosulfonyl(C1- C ₄ ) alkyl, methanesulfonamido (C ₁ -C ₄ ) alkyl, carboxy (C ₁ -C ₄ ) alkyl, (C ₁ -C ₄ )alkoxycarbonyl (C ₁ -C ₄ ) alkane base, tetrahydropyran-4-yl can be optionally substituted by 1-3 R ₇ ;

Or R ₄ , R ₅ and the nitrogen atoms connected to them together form a 3-7 membered nitrogen-containing heterocyclic ring, preferably a 5-6 membered nitrogen-containing heterocyclic ring; the nitrogen-containing heterocyclic ring contains 1-3 N , O or S heteroatom, preferably a 5-6 membered heterocyclic ring containing a nitrogen atom; the nitrogen-containing heterocyclic ring can be optionally substituted by 1-3 R ₈ ;

R ₇ is independently selected from hydrogen, halogen, hydroxy, carboxyl, amino, (C ₁ -C ₄ )alkyl, hydroxy(C ₁ -C ₄ )alkyl, (C ₁ -C ₄ )alkoxy (C ₁ ) -C ₄ ) alkyl, carboxy(C ₁ -C ₄ ) alkyl, (C ₁ -C ₄ )alkoxycarbonyl(C ₁ -C ₄ ) alkyl, (C ₁ -C ₄ ) acyl;

R ₈ is independently selected from hydrogen, hydroxyl, carboxyl, amino, carbamoyl, (C ₁ -C ₄ )alkyl, (C ₁ -C ₄ )alkoxy, (C ₁ -C ₄ )alkoxyformyl , hydroxy (C ₁ -C ₄ ) alkyl.

The present invention preferably relates to indoline compounds of general formula I and their stereoisomers and pharmaceutically acceptable salts,

in,

R ₁ is selected from unsubstituted or phenyl substituted with 1-3 halogens, methyl, methoxy, or is

R ₂ and R ₃ are independently selected from hydrogen, halogen, hydroxyl, methyl, ethyl, methoxy,

选自：

Selected from:

At the same time, the present invention also preferably relates to the indoline compounds of general formula I and their stereoisomers and pharmaceutically acceptable salts,

in,

R ₁ is selected from unsubstituted or phenyl substituted with 1-3 halogens, methyl, methoxy, or is

另一个选自氢、卤素、羟基、甲基、乙基、甲氧基；One of R ₂ and R ₃ is selected from

The other is selected from hydrogen, halogen, hydroxy, methyl, ethyl, methoxy;

选自：

Selected from:

The indoline compounds of the general formula I and their stereoisomers and pharmaceutically acceptable salts of the present invention are preferably selected from the following compounds, but these compounds do not mean any limitation to the present invention:

In addition, the present invention also includes prodrugs of the compounds of the present invention. Prodrugs of the compounds of the present invention are derivatives of general formula I, which themselves may be less active or even inactive, but after administration, are converted under physiological conditions (eg by metabolism, solvolysis or otherwise) into the corresponding biologically active form.

The above-mentioned indoline compounds of general formula I and their stereoisomers and pharmaceutically acceptable salts, the pharmaceutically acceptable salts include salts formed with inorganic acids, organic acids and alkali metal ions ; Described inorganic acid is selected from: hydrochloric acid, hydrobromic acid, hydrofluoric acid, sulfuric acid, phosphoric acid; Described organic acid is selected from: succinic acid, fumaric acid, maleic acid, lactic acid, malic acid, tartaric acid, lemon acid, methanesulfonic acid, ethanesulfonic acid or p-toluenesulfonic acid; the associated alkali metal ions are selected from lithium, sodium or potassium ions.

In the present invention, "halogen" refers to fluorine, chlorine, bromine or iodine; "alkyl" refers to a straight-chain or branched alkyl group; "nitrogen-containing heterocycle" refers to a monocyclic or polycyclic ring containing a nitrogen atom. Ring systems, which are non-aromatic or aromatic.

The present invention can contain the indoline compounds of the above formula I, their stereoisomers and pharmaceutically acceptable salts as active ingredients, and can be mixed with pharmaceutically acceptable carriers or excipients to prepare a composition. The carriers or excipients include diluents, binders, wetting agents, disintegrants, lubricants, glidants and the like known in the art. Diluents include but are not limited to starch, dextrin, sucrose, glucose, lactose, mannitol, sorbitol, xylitol, calcium hydrogen phosphate, etc.; humectants include water, ethanol, isopropanol, etc.; binders include but are not Limited to starch slurry, dextrin, syrup, honey, glucose solution, acacia mucilage, gelatin slurry, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose, polyethylene glycol, etc.; disintegrants Including but not limited to dry starch, microcrystalline cellulose, low-substituted hydroxypropyl cellulose, cross-linked polyvinyl pyrrolidone, cross-linked sodium carboxymethyl cellulose, sodium carboxymethyl starch, sodium dodecyl sulfonate, etc.; Lubricants and glidants include, but are not limited to, talc, silica, polyethylene glycols, and the like.

The pharmaceutical composition of the present invention can be formulated into several dosage forms, including but not limited to injections, tablets, capsules, and the like.

The indoline compounds and their stereoisomers and pharmaceutically acceptable salts of the present invention can be used in combination with other active ingredients to achieve better therapeutic effects.

The present invention also provides the application of the indoline compounds of the general formula I, their stereoisomers and pharmaceutically acceptable salts in the preparation of medicines for preventing and/or treating diseases related to the PD-1/PD-L1 signaling pathway . The diseases related to the PD-1/PD-L1 signaling pathway are selected from cancer, infectious diseases, and autoimmune diseases. The cancer is selected from lung cancer, skin cancer, hematological tumor, glioma, digestive system tumor, breast cancer, lymphoma, nervous system tumor, and melanoma; the infectious disease is selected from bacterial infection and viral infection; The autoimmune disease described is selected from organ-specific, systemic autoimmune disease. Wherein, the organ-specific autoimmune diseases include chronic lymphocytic thyroiditis, hyperthyroidism, insulin-dependent diabetes mellitus, ulcerative colitis, acute idiopathic polyneuritis, and the systemic autoimmune diseases include Rheumatoid arthritis, systemic lupus erythematosus, systemic vasculitis, autoimmune hemolytic anemia.

The positive improvement effect of the present invention is that: the indoline compounds of the present invention have novel chemical structures, have high inhibitory activity on PD-1/PD-L1 interaction in in vitro studies, and can be used for cancer and other various Disease treatment and prevention.

The examples and preparations provided hereinafter further illustrate and illustrate the compounds of the present invention and methods for their preparation. It should be understood that the scope of the following examples and preparations do not limit the scope of the invention in any way.

The following synthetic schemes outline and describe the preparation of compounds of formula I of the present invention, all starting materials were prepared by the means described in these schemes, by methods well known to those of ordinary skill in the art of organic chemistry, or are commercially available. All final derivatives of the present invention are prepared by methods described in these schemes or by methods analogous thereto, which are well known to those of ordinary skill in the art of organic chemistry.

Route one:

(a) using 4-bromo-1H-indole and benzene, substituted benzene or heteroaromatic boronic acid or boronic acid ester as raw materials, obtain intermediate 2 through Suzuki coupling reaction;

(b) with intermediate 2 as raw material, under the action of reducing agent such as sodium cyanoborohydride, indoline intermediate 3 is obtained;

(c) take intermediate 3 and substituted benzoic acid as raw materials, and obtain intermediate 4 containing formyl group through amidation reaction under the condition of condensing agent;

(d) Using intermediate 4 as a raw material, condensation with amine compounds and reduction under the action of sodium cyanoborohydride or sodium triacetoxyborohydride to obtain the target compound of general formula I.

Route two:

(e) take the indoline intermediate 3 and the substituted benzoic acid as raw materials, and obtain the intermediate 5 containing chlorine or bromine through amidation reaction under the condition of the condensing agent;

(f) take intermediate 5 as raw material, obtain intermediate 6 through Suzuki coupling reaction with vinylboronic acid pinacol ester;

(g) with intermediate 6 as raw material, under the effect of oxidizing agent such as sodium periodate, obtain intermediate 4 containing formyl;

(h) Using intermediate 4 as a raw material, condensation with amine compounds and reduction under the action of sodium cyanoborohydride or sodium triacetoxyborohydride to obtain the target compound of general formula I.

Route three:

(i) using indoline intermediate 3 and substituted benzoic acid as raw materials, through amidation reaction under condensing agent conditions, obtain intermediate 7 containing hydroxyl and formyl;

(j) Using intermediate 7 as a raw material, under alkaline conditions, through nucleophilic substitution reaction with halogenated hydrocarbons to prepare intermediate 4;

(k) Using intermediate 4 as a raw material, condensation with an amine compound and reduction under the action of sodium cyanoborohydride or sodium triacetoxyborohydride to obtain the target compound of general formula I.

Route four:

(1) with intermediate 3 and substituted benzoic acid as raw material, make the intermediate 8 containing hydroxyl and chlorine or bromine through amidation reaction under condensing agent condition;

(m) using the intermediate 8 as a raw material, under alkaline conditions, with a halogenated hydrocarbon through a nucleophilic substitution reaction to prepare the intermediate 5;

(n) take intermediate 5 as raw material, and obtain intermediate 6 through Suzuki coupling reaction with vinylboronic acid pinacol ester;

(o) take intermediate 6 as raw material, make intermediate 4 containing formyl group under the action of oxidant such as sodium periodate;

(p) Using intermediate 4 as a raw material, condensation with an amine compound and reduction under the action of sodium cyanoborohydride or sodium triacetoxyborohydride to obtain the target compound of general formula I.

In the above scheme, the definitions of R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are as described in the claims. In intermediates 5 and 8, Y represents chlorine or bromine. The indoline compounds having the general formula I of the present invention can be prepared according to the above reaction scheme.

Detailed ways:

In the following examples, methods for preparing some of the compounds are depicted. It will be appreciated that the following methods, as well as other methods known to those of ordinary skill in the art, are applicable to the preparation of all compounds described herein. The examples are intended to illustrate rather than limit the scope of the invention.

Example 1: (4-(((2-hydroxyethyl)amino)methyl)phenyl)(4-phenylindolin-1-yl)formyl

Step 1: 4-Phenyl-1H-Indole

At room temperature, 4-bromo-1H-indole (10 g, 51.29 mmol), phenylboronic acid (6.26 g, 51.29 mmol), palladium tetrakistriphenylphosphine (1.78 g, 1.54 mmol), potassium carbonate (21.23 g, 153.94 mmol) was dissolved in a mixed solvent of dioxane and water (volume ratio 4:1, 250 mL). Under nitrogen protection, the temperature was raised to 60°C for 10 hours. Cooled to room temperature, suction filtered through a pad of celite, the filtrate was extracted with dichloromethane, the organic layer was washed with saturated brine, concentrated under reduced pressure, and separated by column chromatography to obtain 6.66 g of a white solid with a yield of 67.2%.

Step 2: 4-Phenylindoline

At room temperature, 4-phenyl-1H-indole (1.5 g, 7.77 mmol) was dissolved in glacial acetic acid (9 mL), sodium cyanoborohydride (1.47 g, 23.32 mmol) was slowly added, and the reaction was carried out at room temperature for 2 hours. Under ice bath, pH was adjusted to 9-10 with 40% NaOH solution, extracted with ethyl acetate, the organic layer was washed with saturated brine, concentrated under reduced pressure, and separated by column chromatography to obtain 1.08 g of white solid with a yield of 71.3%.

Step 3: 4-(4-Phenylindoline-1-formyl)benzaldehyde

At room temperature, 4-phenylindoline (0.1 g, 0.51 mmol), 4-formylbenzoic acid (0.08 g, 0.56 mmol), HATU (0.29 g, 0.76 mmol) were dissolved in DMF (5 mL), room temperature Stir for 20 min, add DIPEA (0.33 g, 2.56 mmol), and react at room temperature for 4 hours. The reaction solution was poured into water, a pale yellow solid was precipitated, stirred at room temperature for 20 min, suction filtered, and slurried with ether to obtain 0.149 g of a white solid with a yield of 89.5%.

Step 4: (4-(((2-Hydroxyethyl)amino)methyl)phenyl)(4-phenylindolin-1-yl)formyl (Example 1)

At room temperature, 4-(4-phenylindoline-1-formyl)benzaldehyde (0.08 g, 0.24 mmol) and glacial acetic acid (0.02 g, 0.33 mmol) were dissolved in methanol (5 mL), and stirred at room temperature for 0.5 hour, ethanolamine (0.07 g, 1.14 mmol) was added, and the reaction was carried out at room temperature for 5 hours. Sodium cyanoborohydride (0.08 g, 1.27 mmol) was added, and the reaction was carried out at room temperature for 10 hours. After the reaction was completed, methanol was evaporated, water was added, extracted with dichloromethane, washed with saturated brine, concentrated under reduced pressure, and separated by column chromatography to obtain 0.023 g of a pale yellow solid with a yield of 26.2%.

ESI-MS m/z: 373.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 7.61-7.20 (m, 11H), 7.09 (d, J=6.8 Hz, 1H), 4.53 (s,1H),4.00(t,J＝7.8Hz,2H),3.79(s,2H),3.49(t,J＝5.5Hz,2H),3.12(t,J＝8.0Hz,2H),2.60 (t, J=5.6Hz, 2H), 1.23(s, 1H).

According to the synthetic method of Example 1, using 4-(4-phenylindoline-1-formyl)benzaldehyde as a raw material, reacting with different amine compounds, and then reducing it with sodium cyanoborohydride to prepare and implement Compounds of Examples 2-3.

Example 2: N-(2-((4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 414.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 7.81 (s, 1H), 7.54 (d, J=7.8 Hz, 2H), 7.46 (dd , J＝11.5, 6.0Hz, 6H), 7.41–7.35(m, 1H), 7.29(s, 1H), 7.09(d, J＝7.0Hz, 1H), 4.00(t, J＝8.0Hz, 2H) ,3.76(s,2H),3.18–3.09(m,4H),2.56(t,J=6.4Hz,2H),1.79(s,3H),1.23(s,1H).

Example 3: (S)-(4-((2-(Hydroxymethyl)pyrrolidin-1-yl)methyl)phenyl)(4-phenylindolin-1-yl)formyl

ESI-MS m/z: 413.2 [M+H] ⁺ ;

Example 4: (4-(((2-hydroxyethyl)amino)methyl)-3-methylphenyl)(4-phenylindolin-1-yl)formyl

Step 1: (4-Bromo-3-methylphenyl)(4-phenylindolin-1-yl)formyl

4-Phenylindoline (0.09 g, 0.46 mmol), 4-bromo-3-methylbenzoic acid (0.1 g, 0.47 mmol), HATU (0.26 g, 0.68 mmol) were dissolved in dry DMF at room temperature (5 mL), stir evenly, add DIPEA (0.11 g, 0.92 mmol), and react at room temperature for 2 hours. The reaction solution was poured into cold water, stirred for 15 minutes, and suction filtered to obtain 0.16 g of a white solid with a yield of 90.2%.

Step 2: (3-Methyl-4-vinylphenyl)(4-phenylindolin-1-yl)formyl

At room temperature, (4-bromo-3-methylphenyl)(4-phenylindolin-1-yl)formyl (0.1 g, 0.26 mmol), vinylboronic acid pinacol ester (0.04 g, 0.26 mmol), [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride (0.02 g, 0.027 mmol), cesium carbonate (0.18 g, 0.55 mmol) in 1,4-bis In a mixed solvent of oxane/water (volume ratio 3:1, 8 mL), the reaction was carried out at 90° C. for 1.5 hours under nitrogen protection. The reaction solution was cooled to room temperature, 1,4-dioxane was evaporated, water was added to the system, and the mixture was extracted with ethyl acetate. 0.054 g of white solid was obtained by column chromatography, and the yield was 61.3%.

Step 3: 2-Methyl-4-(4-phenylindoline-1-formyl)benzaldehyde

(3-Methyl-4-vinylphenyl)(4-phenylindolin-1-yl)formyl (0.23 g, 0.68 mmol) was dissolved in 1,4-dioxane/ In the mixed solution of water (volume ratio 5:1, 10 mL), 2% OsO ₄ aqueous solution (1.3 mL) was quickly added, and after stirring for 5 minutes, sodium periodate (0.58 g, 2.7 mmol) was added, and the reaction was stirred at room temperature for 3 hours. . The reaction solution was poured into water, filtered with suction, and dried to obtain 0.21 of an off-white solid with a yield of 91.5%.

Step 4: (4-(((2-Hydroxyethyl)amino)methyl)-3-methylphenyl)(4-phenylindolin-1-yl)formyl (Example 4)

2-Methyl-4-(4-phenylindoline-1-formyl)benzaldehyde (0.08 g, 0.23 mmol) was dissolved in dry dichloromethane (5 mL), glacial acetic acid (0.02 g, 0.35 mmol) was stirred for 10 min, ethanolamine (0.056 g, 0.92 mmol) was added, and the reaction was stirred for 2 hours. Sodium triacetoxyborohydride (0.25 g, 1.18 mmol) was added to the reaction solution, and the reaction was continued at room temperature for 10 hours. Water was added to the reaction solution, the organic layer was evaporated to dryness, and 0.027 g of white solid was obtained by column chromatography with a yield of 30.2%.

ESI-MS m/z: 387.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 8.03 (s, 1H), 7.56–7.44 (m, 5H), 7.40 (s, 3H) ,7.28(s,1H),7.09(s,1H),3.99(m,2H),3.87(s,2H),3.58(s,2H),3.12(m,2H),2.76(s,2H), 2.37(s, 3H), 1.91(s, 1H).

According to the synthetic method of Example 4, using 2-methyl-4-(4-phenylindoline-1-formyl)benzaldehyde as a raw material, by reacting with different amine compounds, and then by triacetoxy The compounds of Examples 5-10 were prepared by reduction with sodium borohydride.

Example 5: N-(2-((2-Methyl-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 428.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 7.87 (s, 1H), 7.43 (d, J=52.1 Hz, 9H), 7.10 (s ,1H),4.00(s,2H),3.75(s,2H),3.20(s,2H),3.12(s,2H),2.65(s,2H),2.35(s,3H),1.82(s, 3H).

Example 6: 2-((2-Methyl-4-(4-phenylindoline-1-formyl)benzyl)amino)ethane-1-sulfonamide

ESI-MS m/z: 450.2 [M+H] ⁺ ;

Example 7: N-(2-((2-Methyl-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)methanesulfonamide

ESI-MS m/z: 464.2[M+H] ⁺ ;

Example 8: (S)-(4-((2-(Hydroxymethyl)pyrrolidin-1-yl)methyl)-3-methylphenyl)(4-phenylindolin-1-yl ) formyl

ESI-MS m/z: 427.2 [M+H] ⁺ ;

Example 9: (2-Methyl-4-(4-phenylindoline-1-formyl)benzyl)-L-proline

ESI-MS m/z: 441.2 [M+H] ⁺ ;

Example 10: (3-Methyl-4-(((tetrahydro-2H-pyran-4-yl)amino)methyl)phenyl)(4-phenylindolin-1-yl)formyl

ESI-MS m/z: 427.2 [M+H] ⁺ ;

Similar to the synthetic method of Example 4, using 4-phenylindoline as raw material, by amidation with 4-bromo-3-methoxybenzoic acid, Suzuki coupling of vinylboronic acid pinacol ester, sodium periodate Oxidation and reductive amination with sodium cyanoborohydride gave the compounds of Examples 11-20.

Example 11: (4-(((2-hydroxyethyl)amino)methyl)-3-methoxyphenyl)(4-phenylindolin-1-yl)formyl

ESI-MS m/z: 403.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 8.08 (s, 1H), 7.64–7.24 (m, 7H), 7.23–7.03 (m, 3H), 4.58(s, 1H), 4.12–3.96(m, 2H), 3.84(s, 3H), 3.79(s, 2H), 3.51(s, 2H), 3.15(dd, J=17.6, 10.1Hz ,2H),2.65(s,2H),1.25(s,1H).

Example 12: N-(2-((2-Methoxy-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 444.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 7.87 (s, 1H), 7.47 (dd, J=17.2, 5.9 Hz, 5H), 7.39 (dt, J=8.4, 4.3Hz, 1H), 7.30 (s, 1H), 7.19–7.14 (m, 2H), 7.11 (d, J=7.0Hz, 1H), 4.02 (t, J=8.0Hz, 2H), 3.84(s, 3H), 3.78(s, 2H), 3.18(dd, J=12.1, 6.1Hz, 2H), 3.14(t, J=8.1Hz, 2H), 2.63(t, J=6.2 Hz, 2H), 1.81(s, 3H), 1.24(s, 1H).

Example 13: 2-((2-Methoxy-4-(4-phenylindoline-1-formyl)benzyl)amino)ethane-1-sulfonamide

ESI-MS m/z: 466.2[M+H] ⁺ ;

Example 14: N-(2-((2-Methoxy-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)methanesulfonamide

ESI-MS m/z: 480.2 [M+H] ⁺ ;

Example 15: (2-Methoxy-4-(4-phenylindoline-1-formyl)benzyl)-D-serine

ESI-MS m/z: 447.2 [M+H] ⁺ ;

Example 16: (2-Methoxy-4-(4-phenylindoline-1-formyl)benzyl)-D-alanine

ESI-MS m/z: 431.2 [M+H] ⁺ ;

Example 17: (S)-3-Hydroxy-4-((2-methoxy-4-(4-phenylindoline-1-formyl)benzyl)amino)butanoic acid

ESI-MS m/z: 461.2[M+H] ⁺ ;

Example 18: (S)-(4-((2-(Hydroxymethyl)pyrrolidin-1-yl)methyl)-3-methoxyphenyl)(4-phenylindoline-1- group) formyl

ESI-MS m/z: 443.2 [M+H] ⁺ ;

Example 19: (2-Methoxy-4-(4-phenylindoline-1-formyl)benzyl)-L-proline

ESI-MS m/z: 456.2[M+H] ⁺ ;

Example 20: (3-Methoxy-4-(((tetrahydro-2H-pyran-4-yl)amino)methyl)phenyl)(4-phenylindolin-1-yl)methan Acyl

ESI-MS m/z: 443.2 [M+H] ⁺ ;

Similar to the synthetic method of Example 11, using 4-phenylindoline as raw material, through amidation with 4-bromo-3,5-dimethoxybenzoic acid, Suzuki coupling of vinylboronic acid pinacol ester, high Sodium iodate oxidation followed by reductive amination with sodium cyanoborohydride gave the compounds of Examples 21-23.

Example 21: (4-(((2-hydroxyethyl)amino)methyl)-3,5-dimethoxyphenyl)(4-phenylindolin-1-yl)formyl

ESI-MS m/z: 433.2 [M+H] ⁺ ;

Example 22: N-(2-((2,6-Dimethoxy-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 474.2 [M+H] ⁺ ;

Example 23: (S)-(4-((2-(Hydroxymethyl)pyrrolidin-1-yl)methyl)-3,5-dimethoxyphenyl)(4-phenylindoline -1-yl)formyl

ESI-MS m/z: 473.2 [M+H] ⁺ ;

Similar to the synthetic method of Example 4, using 4-phenylindoline as a raw material, by amidation with 4-bromo-3-chlorobenzoic acid, Suzuki coupling of vinylboronic acid pinacol ester, sodium periodate oxidation, The compounds of Examples 24 and 25 were prepared by reductive amination with sodium cyanoborohydride.

Example 24: (3-Chloro-4-(((2-hydroxyethyl)amino)methyl)phenyl)(4-phenylindolin-1-yl)formyl

ESI-MS m/z: 407.1 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 8.08 (s, 1H), 7.65 (s, 2H), 7.56 (d, J=6.6 Hz ,1H),7.47(d,J＝2.6Hz,4H),7.42–7.24(m,2H),7.11(d,J＝5.0Hz,1H),4.54(s,1H),4.01(s,2H) ,3.86(s,2H),3.50(d,J=4.4Hz,2H),3.13(t,J=7.3Hz,2H),2.63(s,2H),1.23(s,1H).

Example 25: N-(2-((2-Chloro-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 448.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 8.10 (s, 1H), 7.84 (s, 1H), 7.66 (s, 2H), 7.58 (s, 1H), 7.48(s, 4H), 7.37(d, J=39.1Hz, 2H), 7.13(s, 1H), 4.01(s, 2H), 3.84(s, 2H), 3.16(dd, J=15.6, 7.5Hz, 4H), 2.61(s, 2H), 1.81(s, 3H), 1.24(s, 1H).

Example 26: (3-Hydroxy-4-(((2-hydroxyethyl)amino)methyl)phenyl)(4-phenylindolin-1-yl)formyl

Step 1: 2-Hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde

At room temperature, 4-phenylindoline (1.51 g, 7.74 mmol), 4-formyl-3-hydroxybenzoic acid (1.31 g, 7.89 mmol) were dissolved in dichloromethane (20 mL), and EDCI (1.78 g) was added. g, 9.31 mmol), continue to react for 3h. The reaction solution was washed with water, washed with saturated brine, and evaporated to dryness to obtain 2.27 g of a pale yellow solid with a yield of 85.6%.

Step 2: (3-Hydroxy-4-(((2-hydroxyethyl)amino)methyl)phenyl)(4-phenylindolin-1-yl)formyl (Example 26)

Similar to the synthesis method of Example 1, 2-hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde was used as raw material, and it was prepared by reductive amination with ethanolamine by sodium cyanoborohydride.

ESI-MS m/z: 389.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 7.48 (d, J=4.1 Hz, 4H), 7.42-7.36 (m, 1H), 7.29 (s, 1H), 7.23 (d, J=7.6Hz, 1H), 7.16 (t, J=7.8Hz, 1H), 7.09 (d, J=7.1Hz, 1H), 6.96 (d, J=7.4Hz) ,1H),6.90(s,1H),6.77(t,J＝8.4Hz,1H),4.00(t,J＝8.0Hz,2H),3.92(s,2H),3.53(t,J＝5.6Hz ,2H),3.13(t,J＝8.1Hz,2H),2.65(t,J＝5.5Hz,2H),1.25(s,1H).

Similar to the synthetic method of Example 26, using 2-hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde as raw material, and N-(2-aminoethyl)acetamide through cyanoboron The compound of Example 27 was prepared by sodium hydride reductive amination.

Example 27: N-(2-((2-Hydroxy-4-(4-phenylindoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 430.2[M+H]+; 1H NMR (600MHz, DMSO-d ₆ ) δ 7.86(s, 1H), 7.48(d, J=4.2Hz, 4H), 7.39(dt, J=8.6, 4.4Hz, 1H), 7.29(s, 1H), 7.22(d, J=7.7Hz, 1H), 7.16(t, J=7.8Hz, 1H), 7.09(d, J=7.4Hz, 1H), 6.96(d, J＝7.4Hz, 1H), 6.90(s, 1H), 6.76(d, J＝8.3Hz, 1H), 4.00(t, J＝8.1Hz, 2H), 3.86(s, 2H), 3.18(dd, J＝12.2, 6.2Hz, 2H), 3.13(t, J＝8.2Hz, 2H), 2.60(t, J＝6.4Hz, 2H), 1.81(s, 3H), 1.24( s,1H).

Example 28: (4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(4-(((2-hydroxyethyl yl)amino)methyl)phenyl)formyl

Step 1: 4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)-1H-indole

At room temperature, 4-bromo-1H-indole (10 g, 51.29 mmol), 2-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)-4,4 ,5,5-tetramethyl-1,3,2-dioxaborolane (13.45g, 51.29mmol), tetrakistriphenylphosphine palladium (1.78g, 1.54mmol), potassium carbonate (21.23g, 153.94 mmol) was dissolved in a mixed solvent of dioxane and water (volume ratio 4:1, 250 mL). Under nitrogen protection, the temperature was raised to 60°C for 13 hours. Cooled to room temperature, suction filtered through a pad of celite, the filtrate was extracted with dichloromethane, the organic layer was washed with saturated brine, concentrated under reduced pressure, and separated by column chromatography to obtain 8.68 g of a white solid with a yield of 67.4%.

Step 2: 4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline

4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)-1H-indole (2 g, 7.97 mmol) was dissolved in glacial acetic acid (10 mL) at room temperature , Sodium cyanoborohydride (1.51 g, 23.90 mmol) was slowly added, and the reaction was carried out at room temperature for 3 hours. Under ice bath, the pH was adjusted to 9 with NaOH solution, extracted with dichloromethane, the organic layer was washed with saturated brine, the organic layer was evaporated and separated by column chromatography to obtain 1.42 g of a white solid with a yield of 70.4%.

Step 3: 4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)benzaldehyde

At room temperature, 4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline (0.5 g, 1.98 mmol), 4-formylbenzoic acid (0.33 g, 2.17 mmol) and HATU (1.13 g, 2.96 mmol) were dissolved in DMF (10 mL), stirred at room temperature for 20 min, added DIPEA (1.28 g, 9.88 mmol), and reacted at room temperature for 5 hours. The reaction solution was poured into water, a pale yellow solid was precipitated, stirred at room temperature for 30 min, suction filtered, and slurried with ether to obtain 0.70 g of a white solid with a yield of 92.5%.

Step 4: (4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(4-(((2-hydroxyethyl )amino)methyl)phenyl)formyl (Example 28)

At room temperature, 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)benzaldehyde (0.08 g, 0.21 mmol), glacial acetic acid (0.02g, 0.31mmol) were dissolved in DMF (5mL), stirred at room temperature for 0.5 hours, added ethanolamine (0.06g, 1.04mmol), reacted at room temperature for 5 hours, added sodium cyanoborohydride (0.07g, 1.04 mmol), and reacted at room temperature for 10 hours. After the reaction was completed, the reaction solution was poured into water, extracted with dichloromethane, and separated by column chromatography to obtain 0.025 g of an off-white solid with a yield of 28.2%.

ESI-MS m/z: 431.2 [M+H] ⁺ ;

Synthesis similar to Example 28, using 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)benzaldehyde As starting material, the compound of Example 29 was prepared with N-(2-aminoethyl)acetamide under the reductive amination of sodium cyanoborohydride.

Example 29: N-(2-((4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl) Benzyl)amino)ethyl)acetamide

ESI-MS m/z: 472.2 [M+H] ⁺ ;

Example 30: (4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(4-(((2-hydroxyethyl yl)amino)methyl)-3-methylphenyl)formyl

Step 1: (4-Bromo-3-methylphenyl)(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl ) formyl

At room temperature, 4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline (0.9 g, 3.56 mmol), 4-bromo-3-methyl Benzoic acid (0.76 g, 3.56 mmol) and HATU (2.03 g, 5.33 mmol) were dissolved in anhydrous DMF (10 mL), stirred evenly, added DIPEA (0.92 g, 7.12 mmol), and reacted at room temperature for 3 hours. The reaction solution was poured into cold water, stirred for 15 minutes, and suction filtered to obtain 1.37 g of a white solid with a yield of 85.5%.

Step 2: (4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(3-methyl-4-vinylbenzene group) formyl

(4-Bromo-3-methylphenyl)(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1- yl)formyl (0.1 g, 0.22 mmol), vinylboronic acid pinacol ester (0.04 g, 0.26 mmol), [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride ( 0.016 g, 0.025 mmol) and cesium carbonate (0.14 g, 0.44 mmol) were dissolved in a mixed solvent of 1,4-dioxane/water (volume ratio 3:1, 8 mL), and reacted at 95 °C for 10 under nitrogen protection. Hour. The reaction solution was cooled to room temperature, 1,4-dioxane was evaporated, water was added to the system, extracted with dichloromethane, and 0.042 g of a white solid was obtained by column chromatography with a yield of 47.6%.

Step 3: 4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-methylbenzaldehyde

(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(3-methyl-4-vinyl) at room temperature Phenyl)formyl (0.2 g, 0.50 mmol) was dissolved in a mixed solution of 1,4-dioxane/water (volume ratio 5:1, 10 mL), and a 2% aqueous OsO ₄ solution (1.1 mL) was quickly added After stirring for 5 minutes, sodium periodate (0.43 g, 2.0 mmol) was added, and the reaction was stirred at room temperature for 5 hours. The reaction solution was poured into water, filtered with suction, and dried to obtain 0.19 g of an off-white solid with a yield of 95.5%.

Step 4: (4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(4-(((2-hydroxyethyl )amino)methyl)-3-methylphenyl)formyl (Example 30)

4-(4-(2,3-Dihydrobenzo[b][1,4]dioxin-6-yl)indoline-1-formyl)-2-methylbenzaldehyde (0.07g , 0.18 mmol) was dissolved in dry dichloromethane (5 mL), glacial acetic acid (0.016 g, 0.27 mmol) was added and stirred for 10 min, ethanolamine (0.055 g, 0.90 mmol) was added, and the reaction was stirred for 2 hours. Sodium triacetoxyborohydride (0.19 g, 0.90 mmol) was added to the reaction solution, and the reaction was continued at room temperature for 12 hours. Water was added to the reaction solution, the organic layer was evaporated to dryness, and 0.028 g of white solid was obtained by column chromatography with a yield of 34.4%.

ESI-MS m/z: 445.2 [M+H] ⁺ ;

Similar to the synthetic method of Example 30, 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2 - methylbenzaldehyde is used as raw material, and the compounds of Examples 31-35 are prepared by reductive amination with amine compounds through sodium cyanoborohydride.

Example 31: N-(2-((4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl) -2-Methylbenzyl)amino)ethyl)acetamide

ESI-MS m/z: 486.2 [M+H] ⁺ ;

Example 32: N-(2-((4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl) -2-Methylbenzyl)amino)ethyl)methanesulfonamide

ESI-MS m/z: 522.2 [M+H] ⁺ ;

Example 33: (4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-methylbenzyl base)-D-serine

ESI-MS m/z: 489.2 [M+H] ⁺ ;

Example 34: (4-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-methylbenzyl base)-D-alanine

ESI-MS m/z: 473.2 [M+H] ⁺ ;

Example 35: (S)-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indolin-1-yl)(4-((2 -(Hydroxymethyl)pyrrolidin-1-yl)methyl)-3-methylphenyl)formyl

ESI-MS m/z: 485.2 [M+H] ⁺ ;

Example 36: 3-((2-(((2-hydroxyethyl)amino)methyl)-5-(4-phenylindoline-1-formyl)phenoxy)methyl)benzyl Nitrile

Step 1: 3-((2-Formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)benzonitrile

2-Hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde (0.6 g, 1.75 mmol), 3-(bromomethyl)benzonitrile (0.41 g, 2.1 mmol) were mixed at room temperature ) and cesium carbonate (1.14 g, 3.5 mmol) were dissolved in DMF (10 mL), and the temperature was raised to 75° C. to react for 1.5 hours. The reaction solution was cooled to room temperature, poured into water, a white solid was precipitated, stirred at room temperature for 20 min, and suction filtered to obtain 0.65 g of a white solid with a yield of 81.2%.

Step 2: 3-((2-(((2-hydroxyethyl)amino)methyl)-5-(4-phenylindoline-1-formyl)phenoxy)methyl)benzonitrile (Example 36)

At room temperature, 3-((2-formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)benzonitrile (0.07 g, 0.15 mmol), glacial acetic acid ( 0.01 g, 0.167 mmol) was dissolved in dichloromethane (5 mL), stirred at room temperature for 0.5 hours, added ethanolamine (0.05 g, 0.82 mmol), reacted at room temperature for 3 hours, added sodium triacetoxyborohydride (0.16 g, 0.75 mmol) ) for 10 hours at room temperature. The reaction solution was washed with water, washed with brine, concentrated under reduced pressure, and separated by column chromatography to obtain 0.013 g of a white solid with a yield of 16.3%.

ESI-MS m/z: 504.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 8.01 (d, J=74.6 Hz, 2H), 7.83 (dd, J=13.5, 7.8 Hz ,2H),7.63(t,J＝7.7Hz,1H),7.48(d,J＝4.1Hz,5H),7.40(dd,J＝8.5,4.2Hz,1H),7.26(s,2H),7.17 (d, J=7.4Hz, 1H), 7.10(d, J=6.8Hz, 1H), 5.28(s, 2H), 4.53(s, 1H), 3.92(s, 2H), 3.83(s, 2H) ,3.51(s,2H),3.11(t,J=8.0Hz,2H),2.63(t,J=5.4Hz,2H),1.24(s,1H).

Synthesis similar to Example 36, using 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2 -methylbenzaldehyde is used as raw material, and (S)-piperidine-2-carboxylic acid is subjected to reductive amination with sodium cyanoborohydride to prepare the compound of Example 37.

Example 37: (S)-1-(2-((3-cyanobenzyl)oxy)-4-(4-phenylindoline-1-formyl)benzyl)piperidine-2- Formic acid

ESI-MS m/z: 572.3 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 8.02 (d, J=88.8 Hz, 2H), 7.82 (dd, J=13.6, 7.5 Hz ,2H),7.62(t,J＝7.4Hz,1H),7.50(dd,J＝26.4,5.2Hz,5H),7.40(d,J＝3.6Hz,1H),7.28(d,J＝28.8Hz ,2H),7.19(d,J=7.1Hz,1H),7.11(d,J=4.8Hz,1H),5.28(s,2H),3.94–3.83(m,3H),3.73(d,J= 14.4Hz, 1H), 3.24(s, 1H), 3.13–3.08(m, 2H), 2.95(s, 1H), 2.32(s, 1H), 1.81(s, 2H), 1.52(s, 3H), 1.42(s,1H).

Example 38: 5-((2-(((2-hydroxyethyl)amino)methyl)-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine- 3-carbonitrile

Step 1: 5-((2-Formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-3-carbonitrile

2-Hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde (0.6 g, 1.75 mmol), 5-(chloromethyl)pyridine-3-carbonitrile (0.35 g) were mixed at room temperature , 2.3 mmol) and cesium carbonate (1.14 g, 3.5 mmol) were dissolved in DMF (10 mL), and the temperature was raised to 30° C. to react for 3 hours. The reaction solution was cooled to room temperature, poured into water, extracted with ethyl acetate, the organic layer was washed with saturated brine, and the solvent was evaporated to obtain 0.58 g of a pale yellow solid with a yield of 72.6%.

Step 2: 5-((2-(((2-hydroxyethyl)amino)methyl)-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-3 - Formonitrile (Example 38)

5-((2-Formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-3-carbonitrile (0.07 g, 0.15 mmol) was dissolved in DMF ( 5 mL), ethanolamine (0.03 g, 0.49 mmol) and glacial acetic acid (0.05 g, 0.83 mmol) were added to react at room temperature for 2 hours, and sodium cyanoborohydride (0.03 g, 0.48 mmol) was added to react at room temperature for 10 hours. The reaction solution was poured into water, extracted with ethyl acetate, washed with saturated brine, concentrated under reduced pressure, and subjected to column chromatography to obtain 0.0135 g of an off-white solid with a yield of 17.6%.

ESI-MS m/z: 505.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 9.01 (d, J=10.4 Hz, 2H), 8.44 (s, 1H), 7.51–7.46 (m, 5H), 7.40(dd, J=8.7, 4.3Hz, 1H), 7.30(s, 1H), 7.22–7.08(m, 3H), 6.76(t, J=8.8Hz, 1H), 5.33( s, 2H), 4.57(s, 1H), 3.95(t, J=7.1Hz, 2H), 3.86(s, 2H), 3.51(d, J=4.8Hz, 2H), 3.12(t, J=8.1 Hz,2H),2.65(s,2H).

Similar to the synthetic method of Example 38, using 5-((2-formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-3-carbonitrile as raw material, The compounds of Examples 39-42 were prepared by reductive amination with amine compounds through sodium cyanoborohydride.

Example 39: N-(2-((2-((5-Cyanopyridin-3-yl)methyleneoxy)-4-(4-phenylindoline-1-formyl)benzyl) Amino)ethyl)acetamide

ESI-MS m/z: 546.2 [M+H] ⁺ ; ¹ H NMR (600 MHz, DMSO-d ₆ ) δ 9.00 (d, J=11.1 Hz, 2H), 8.44 (s, 1H), 7.83 (s ,1H),7.48(d,J＝3.7Hz,5H),7.40(d,J＝4.2Hz,1H),7.29(s,2H),7.20(d,J＝7.1Hz,1H),7.11(d , J=5.4Hz, 1H), 5.32(s, 2H), 3.95(s, 2H), 3.82(s, 2H), 3.17(d, J=5.9Hz, 2H), 3.12(t, J=7.7Hz) ,2H),2.61(t,J=5.5Hz,2H),1.79(s,3H).

Example 40: (2-((5-Cyanopyridin-3-yl)methyleneoxy)-4-(4-phenylindoline-1-formyl)benzyl)-D-alanine

ESI-MS m/z: 533.2 [M+H] ⁺ ;

Example 41: (S)-5-((2-((2-(Hydroxymethyl)pyrrolidin-1-yl)methyl)-5-(4-phenylindoline-1-formyl) Phenoxy)methyl)pyridine-3-carbonitrile

ESI-MS m/z: 545.3 [M+H] ⁺ ;

Example 42: (2-((5-Cyanopyridin-3-yl)methyleneoxy)-4-(4-phenylindoline-1-formyl)benzyl)-L-proline

ESI-MS m/z: 559.2 [M+H] ⁺ ;

Example 43: 4-((2-(((2-hydroxyethyl)amino)methyl)-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine- 2-carbonitrile

Step 1: 4-((2-Formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-2-carbonitrile

2-Hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde (2 g, 5.83 mmol), 4-(bromomethyl)pyridine-2-carbonitrile (1.37 g, 7 mmol), Cesium carbonate (3.8 g, 11.66 mmol) was dissolved in DMF (15 mL), and the temperature was raised to 75° C. to react for 1.5 hours. The reaction solution was cooled to room temperature, poured into water, a white solid was precipitated, stirred at room temperature for 1 hour, and suction filtered to obtain 2.32 g of a white solid with a yield of 86.6%.

Step 2: 4-((2-(((2-hydroxyethyl)amino)methyl)-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-2 - Formonitrile (Example 43)

Similar to the synthetic method of Example 38, using 4-((2-formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-2-carbonitrile as raw material, It was prepared by reductive amination with ethanolamine by sodium cyanoborohydride.

ESI-MS m/z: 505.2 [M+H] ⁺ ;

Similar to the synthetic method of Example 38, using 4-((2-formyl-5-(4-phenylindoline-1-formyl)phenoxy)methyl)pyridine-2-carbonitrile as raw material, The compounds of Examples 44-47 were prepared by reductive amination with amine compounds through sodium cyanoborohydride.

Example 44: N-(2-((2-((2-Cyanopyridin-4-yl)methyleneoxy)-4-(4-phenylindoline-1-formyl)benzyl) Amino)ethyl)acetamide

ESI-MS m/z: 546.2 [M+H] ⁺ ;

Example 45: (2-((2-Cyanopyridin-4-yl)methyleneoxy)-4-(4-phenylindoline-1-formyl)benzyl)-D-alanine

ESI-MS m/z: 533.2 [M+H] ⁺ ;

Example 46: (S)-4-((2-((2-(Hydroxymethyl)pyrrolidin-1-yl)methyl)-5-(4-phenylindoline-1-formyl) Phenoxy)methyl)pyridine-2-carbonitrile

ESI-MS m/z: 545.3 [M+H] ⁺ ;

Example 47: (2-((2-Cyanopyridin-4-yl)methyleneoxy)-4-(4-phenylindoline-1-formyl)benzyl)-L-proline

ESI-MS m/z: 559.2 [M+H] ⁺ ;

Example 48: 3-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2- (((2-hydroxyethyl)amino)methyl)phenoxy)methyl)benzonitrile

Step 1: 4-(4-(2,3-Dihydrobenzo[b][1,4]dioxin-6-yl)indoline-1-formyl)-2-hydroxybenzaldehyde

At room temperature, 4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline (0.57 g, 2.24 mmol), 4-formyl-3-hydroxyl Benzoic acid (0.38 g, 2.29 mmol) was dissolved in anhydrous dichloromethane (10 mL), stirred evenly, EDCI (0.51 g, 2.69 mmol) was added, and the reaction was carried out at room temperature for 5 hours. The reaction solution was washed with water and saturated brine, and the solvent was evaporated to obtain 0.73 g of a pale yellow solid with a yield of 80.7%.

Step 2: 3-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-methyl Acylphenoxy)methyl)benzonitrile

At room temperature, 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-hydroxybenzaldehyde ( 0.39 g, 0.97 mmol), 3-(bromomethyl) benzonitrile (0.23 g, 1.16 mmol), and cesium carbonate (0.63 g, 1.94 mmol) were dissolved in anhydrous DMF (5 mL), and the temperature was raised to 75 °C and reacted for 2 hours . The reaction solution was cooled to room temperature, poured into cold water, stirred for 20 minutes, and filtered with suction to obtain 0.44 g of a white solid with a yield of 88.4%.

Step 3: 3-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl)-2-( ((2-hydroxyethyl)amino)methyl)phenoxy)methyl)benzonitrile (Example 48)

Similar to the preparation method of Example 36, 3-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl )-2-formylphenoxy)methyl)benzonitrile as raw material, and ethanolamine is prepared by reductive amination with sodium triacetoxyborohydride.

ESI-MS m/z: 562.2[M+H] ⁺ ;

Example 49: 5-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2- (((2-hydroxyethyl)amino)methyl)phenoxy)methyl)pyridine-3-carbonitrile

Step 1: 5-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-methyl Acylphenoxy)methyl)pyridine-3-carbonitrile

At room temperature, 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-hydroxybenzaldehyde ( 2g, 4.99mmol), 5-(chloromethyl)pyridine-3-carbonitrile (0.99g, 6.48mmol), cesium carbonate (3.25g, 9.98mmol) were dissolved in DMF (20mL), and the temperature was raised to 30°C for reaction 5 Hour. The reaction solution was poured into water, extracted with dichloromethane, the organic layer was washed with saturated brine, and the solvent was evaporated to obtain 1.97 g of an off-white solid with a yield of 76.5%.

Step 2: 5-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl)-2-( ((2-hydroxyethyl)amino)methyl)phenoxy)methyl)pyridine-3-carbonitrile (Example 49)

5-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-formylbenzene Oxy)methyl)pyridine-3-carbonitrile (0.078g, 0.15mmol) was dissolved in DMF (5mL), ethanolamine (0.03g, 0.49mmol), glacial acetic acid (0.05g, 0.83mmol) were added, and the reaction was carried out at room temperature for 1 hour, sodium cyanoborohydride (0.03 g, 0.48 mmol) was added, and the reaction was carried out at room temperature for 15 hours. The reaction solution was poured into water, extracted with dichloromethane, washed with saturated brine, concentrated under reduced pressure, and subjected to column chromatography to obtain 0.0188 g of a white solid with a yield of 22.3%.

ESI-MS m/z: 563.2[M+H] ⁺ ;

Synthesis similar to Example 49, using 5-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-methan Acyl)-2-formylphenoxy)methyl)pyridine-3-carbonitrile was used as raw material, and the compounds of Examples 50-53 were prepared by reductive amination with amine compounds through sodium cyanoborohydride.

Example 50: N-(2-((2-((5-cyanopyridin-3-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b][1 ,4]Dioxan-6-yl)indoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 604.3 [M+H] ⁺ ;

Example 51: N-(2-((2-((5-cyanopyridin-3-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b][1 ,4]Dioxan-6-yl)indoline-1-formyl)benzyl)amino)ethyl)methanesulfonamide

ESI-MS m/z: 640.2 [M+H] ⁺ ;

Example 52: (S)-5-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl )-2-((2-(hydroxymethyl)pyrrolidin-1-yl)methyl)phenoxy)methyl)pyridine-3-carbonitrile

ESI-MS m/z: 603.3 [M+H] ⁺ ;

Example 53: (2-((5-Cyanopyridin-3-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b][1,4]dioxin -6-yl)indoline-1-formyl)benzyl)-L-proline

ESI-MS m/z: 617.2 [M+H] ⁺ ;

Example 54: 4-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxin-6-yl)indoline-1-formyl)-2- (((2-hydroxyethyl)amino)methyl)phenoxy)methyl)pyridine-2-carbonitrile

Step 1: 4-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-methyl Acylphenoxy)methyl)pyridine-2-carbonitrile

At room temperature, 4-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-hydroxybenzaldehyde ( 0.3g, 0.75mmol), 4-(bromomethyl)-2-cyanopyridine (0.19g, 0.97mmol), cesium carbonate (0.49g, 1.50mmol) were dissolved in anhydrous DMF (3mL), and reacted at 30°C 2 hours. The reaction solution was poured into cold water, stirred for 20 minutes, extracted with ethyl acetate three times, washed with saturated brine once, and evaporated to dryness to obtain 0.31 g of a pale yellow solid with a yield of 79.6%.

Step 2: 4-((5-(4-(2,3-Dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl)-2-( ((2-hydroxyethyl)amino)methyl)phenoxy)methyl)pyridine-2-carbonitrile (Example 54)

4-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-formylbenzene Oxy)methyl)pyridine-2-carbonitrile (0.08g, 0.15mmol) was dissolved in dry dichloromethane (5mL), glacial acetic acid (0.02g, 0.23mmol) was added and stirred for 10 minutes, ethanolamine (0.047g) was added. , 0.77 mmol), and the reaction was stirred for 2 hours. Sodium triacetoxyborohydride (0.16 g, 0.77 mmol) was added to the reaction solution, and the reaction was continued at room temperature for 15 hours. Water was added to the reaction solution, the organic layer was evaporated to dryness, and 0.029 g of white solid was obtained by column chromatography with a yield of 33.5%.

ESI-MS m/z: 563.2[M+H] ⁺ ;

Synthesis similar to Example 54 was performed with 4-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-methan Acyl)-2-formylphenoxy)methyl)pyridine-2-carbonitrile was used as raw material, and the compounds of Examples 55-59 were prepared by reductive amination with amine compounds through sodium cyanoborohydride.

Example 55: N-(2-((2-((2-cyanopyridin-4-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b][1 ,4]Dioxan-6-yl)indoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 604.3 [M+H] ⁺ ;

Example 56: (2-((2-Cyanopyridin-4-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b][1,4]dioxin -6-yl)indoline-1-formyl)benzyl)-D-alanine

ESI-MS m/z: 591.2 [M+H] ⁺ ;

Example 57: (S)-4-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-carboxyl )-2-((2-(hydroxymethyl)pyrrolidin-1-yl)methyl)phenoxy)methyl)pyridine-2-carbonitrile

ESI-MS m/z: 603.3 [M+H] ⁺ ;

Example 58: (2-((2-Cyanopyridin-4-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b][1,4]dioxin -6-yl)indoline-1-formyl)benzyl)-L-proline

ESI-MS m/z: 617.2 [M+H] ⁺ ;

Example 59: (2S,4S)-1-(2-((2-cyanopyridin-4-yl)methyleneoxy)-4-(4-(2,3-dihydrobenzo[b]) [1,4]Dioxan-6-yl)indoline-1-formyl)benzyl)-4-hydroxypyrrolidine-2-carboxylic acid

ESI-MS m/z: 633.2 [M+H] ⁺ ;

Example 60: N-(2-((2-((2-cyanopyridin-4-yl)methyleneoxy)-4-(4-(3,4-dimethoxyphenyl)indole Line-1-formyl)benzyl)amino)ethyl)acetamide

Step 1: 4-(3,4-Dimethoxyphenyl)indoline

According to the preparation method of 4-phenylindoline, 3,4-dimethoxyphenylboronic acid was used instead of phenylboronic acid.

Step 2: 4-(4-(3,4-Dimethoxyphenyl)indoline-1-formyl)-2-hydroxybenzaldehyde

Following the preparation of 2-hydroxy-4-(4-phenylindoline-1-formyl)benzaldehyde, substituting 4-(3,4-dimethoxyphenyl)indoline for 4-phenyl Indoline system.

Step 3: 4-((5-(4-(3,4-Dimethoxyphenyl)indoline-1-formyl)-2-formylphenoxy)methyl)pyridine-2-methyl Nitrile

According to 4-((5-(4-(2,3-dihydrobenzo[b][1,4]dioxan-6-yl)indoline-1-formyl)-2-formylbenzene Method for the preparation of oxy)methyl)pyridine-2-carbonitrile, substituting 4-(4-(3,4-dimethoxyphenyl)indoline-1-formyl)-2-hydroxybenzaldehyde 4-(4-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl) indoline-1-formyl)-2-hydroxybenzaldehyde obtained.

Step 4: N-(2-((2-((2-cyanopyridin-4-yl)methyleneoxy)-4-(4-(3,4-dimethoxyphenyl)indoline -1-Formyl)benzyl)amino)ethyl)acetamide (Example 60)

Synthesis similar to Example 54, using 4-((5-(4-(3,4-dimethoxyphenyl)indoline-1-formyl)-2-formylphenoxy)methyl ) pyridine-2-carbonitrile as raw material, and N-(2-aminoethyl)acetamide was subjected to reductive amination with sodium triacetoxyborohydride to prepare the compound of Example 60.

ESI-MS m/z: 606.3 [M+H] ⁺ ;

Similar to the synthetic method of Example 60, using substituted phenylboronic acid as raw material, through coupling with 4-bromoindoline Suzuki, 4-formyl-3-hydroxybenzoic acid condensation, 4-(bromomethyl)pyridine-2- Nucleophilic substitution of carbonitrile followed by reductive amination with N-(2-aminoethyl)acetamide via sodium triacetoxyborohydride gave the compounds of Examples 61-63.

Example 61: N-(2-((2-((2-cyanopyridin-4-yl)methyleneoxy)-4-(4-(3-methoxy-4-methylphenyl) Indoline-1-formyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 590.3 [M+H] ⁺ ;

Example 62: N-(2-((4-(4-(4-Chlorophenyl)indoline-1-formyl)-2-((2-cyanopyridin-4-yl)methyleneoxy yl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 580.3 [M+H] ⁺ ;

Example 63: N-(2-((2-((2-cyanopyridin-4-yl)methyleneoxy)-4-(4-(4-fluorophenyl)indoline-1-methyl Acyl)benzyl)amino)ethyl)acetamide

ESI-MS m/z: 564.2[M+H] ⁺ ;

Study on the biological activity of the compounds of the present invention

Homogenouse Time-Resolved Fluorescence (HTRF) assay was used to detect the ability of the compounds of the present invention to inhibit the interaction of PD-1/PD-L1. The detection kit was purchased from CisBio (CAT#63ADK000CPAPEG), which contains Anti-Tag1-Cyptate, Anti-Tag2-XL665/d2, Tag1-PD-L1, Tag2-PD-1, Dilution Buffer, Detection Buffer and other experiments required reagents.

Experimental steps: PD-1 recombinant protein and PD-L1 recombinant protein were diluted to 500nM and 50nM with Dilution Buffer, respectively. Dilute 4mM small molecule compounds dissolved in DMSO 20-fold to 200uM with Dilution Buffer. Four-fold serial dilutions were made with Dilution Buffer containing 5% DMSO. At the same time, dilute 600 uM of PD-1/PD-L1 inhibitor dissolved in DMSO by 20-fold to 30 uM with Dilution Buffer, and use four-fold gradient dilution with Dilution Buffer containing 5% DMSO. Add 2uL of diluted test compound, 4uL of diluted PD-1 and 4uL of diluted PDL-1 to 384 wells in sequence. Mix well and leave at room temperature for 15min. Dilute anti-Tag1-Eu ³⁺ (1:25) and anti-Tag2-XL665 (1:100) with Detection buffer. Then, equal volumes of the diluted detection reagents were mixed, and 10 μL of antibody mixture was added to each reaction well. The membrane was incubated at room temperature for 2 h. Fluorescence signal (320nm excitation, 665nm, 615nm emission) was detected with an ENVISION (Perkinelmer) instrument. Each compound was tested at 8-12 concentrations.

The activity results of compounds inhibiting PD-1/PD-L1 interaction are shown in Table 1.

Table 1 Activity range or _IC50 of the compounds of the present invention for inhibiting PD-1/PD-L1 interaction. The ranges are as follows: A = 1 nM - 100 nM; B = 100.01 nM - 1 μM; C = 1.01 μM - 20 μM.

The HTRF test results showed that the example compounds could significantly inhibit the PD-1/PD-L1 interaction at the molecular level. The compounds are expected to exhibit positive effects in the treatment of diseases related to PD-1/PD-L1 interaction.

Claims (18)

1. Indoline compounds of general formula I and pharmaceutically acceptable salts thereof,

wherein,

R₁selected from unsubstituted or substituted by 1-3R₆Substituted phenyl, or

R₆Independently selected from halogen, (C)₁-C₄) Alkyl, (C)₁-C₄) An alkoxy group;

R₂、R₃each independently selected from hydrogen, halogenHydroxy, (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxy radical,

R₉Independently selected from cyano, methanesulfonyl, acetamido, carbamoyl;

R₄、R₅independently selected from hydrogen, (C)₁-C₄) Alkyl, (C)₃-C₈) Cycloalkyl, hydroxy (C)₁-C₄) Alkyl, amino (C)₁-C₄) Alkyl, carbamoyl (C)₁-C₄) Alkyl, aminosulfonyl (C)₁-C₄) Alkyl, methanesulfonamide group (C)₁-C₄) Alkyl, carboxyl (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxycarbonyl (C)₁-C₄) Alkyl, tetrahydropyran-4-yl; said (C)₁-C₄) Alkyl, (C)₃-C₈) Cycloalkyl, hydroxy (C)₁-C₄) Alkyl, amino (C)₁-C₄) Alkyl, carbamoyl (C)₁-C₄) Alkyl, aminosulfonyl (C)₁-C₄) Alkyl, methanesulfonamide group (C)₁-C₄) Alkyl, carboxyl (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxycarbonyl (C)₁-C₄) Alkyl, tetrahydropyran-4-yl may optionally be substituted with 1-3R₇Substitution; r₄、R₅Not hydrogen at the same time;

or R₄、R₅And the nitrogen atom to which they are attached form a 3-to 7-membered nitrogen-containing heterocyclic ring; the nitrogen-containing heterocycle contains 1-3 heteroatoms of N, O or S; the nitrogen-containing heterocycle may be optionally substituted with 1 to 3R₈Substitution;

R₇independently selected from hydrogen, halogen, hydroxyl, carboxyl, amino and (C)₁-C₄) Alkyl, hydroxy (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxy (C)₁-C₄) Alkyl, carboxyl (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxy formyl radical(C₁-C₄) Alkyl, (C)₁-C₄) An acyl group;

R₈independently selected from hydrogen, hydroxy, carboxy, amino, carbamoyl, (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxy group, (C)₁-C₄) Alcoxyl formyl group and hydroxyl group (C)₁-C₄) An alkyl group.

2. Indoline compounds of the general formula I according to claim 1 and pharmaceutically acceptable salts thereof,

R₄、R₅independently selected from hydrogen, (C)₁-C₄) Alkyl, (C)₃-C₈) Cycloalkyl, hydroxy (C)₁-C₄) Alkyl, amino (C)₁-C₄) Alkyl, carbamoyl (C)₁-C₄) Alkyl, aminosulfonyl (C)₁-C₄) Alkyl, methanesulfonamide group (C)₁-C₄) Alkyl, carboxyl (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxycarbonyl (C)₁-C₄) Alkyl, tetrahydropyran-4-yl; said (C)₁-C₄) Alkyl, (C)₃-C₈) Cycloalkyl, hydroxy (C)₁-C₄) Alkyl, amino (C)₁-C₄) Alkyl, carbamoyl (C)₁-C₄) Alkyl, aminosulfonyl (C)₁-C₄) Alkyl, methanesulfonamide group (C)₁-C₄) Alkyl, carboxyl (C)₁-C₄) Alkyl, (C)₁-C₄) Alkoxycarbonyl (C)₁-C₄) Alkyl, tetrahydropyran-4-yl may optionally be substituted with 1-3R₇Substitution; r₄、R₅Not hydrogen at the same time;

or R₄、R₅And together with the nitrogen atom to which they are attached form a 5-6 membered nitrogen containing heterocyclic ring.

3. Indoline compounds of the general formula I and pharmaceutically acceptable salts thereof according to claim 1, wherein the nitrogen-containing heterocycle is a 5-6 membered heterocycle containing one nitrogen atom.

4. Indoline compounds of the general formula I according to any one of claims 1 to 3 and pharmaceutically acceptable salts thereof,

R₁selected from phenyl which is unsubstituted or substituted by 1 to 3 halogen, methyl, methoxy, or

5. Indoline compounds of the general formula I according to any one of claims 1 to 3 and pharmaceutically acceptable salts thereof,

R₂、R₃each independently selected from hydrogen, halogen, hydroxy, methyl, ethyl, methoxy,

6. Indoline compounds of the general formula I according to claim 4 and pharmaceutically acceptable salts thereof,

R₂、R₃each independently selected from hydrogen, halogen, hydroxy, methyl, ethyl, methoxy,

7. Indoline compounds of the general formula I according to any one of claims 1-3, 6 and pharmaceutically acceptable salts thereof,

R₂、R₃one of them is selected from

And the other is selected from hydrogen, halogen, hydroxyl, methyl, ethyl and methoxy.

8. Indoline compounds of the general formula I according to claim 4 and pharmaceutically acceptable salts thereof,

R₂、R₃one of them is selected from

And the other is selected from hydrogen, halogen, hydroxyl, methyl, ethyl and methoxy.

9. Indoline compounds of the general formula I according to claim 5 and pharmaceutically acceptable salts thereof,

R₂、R₃one of them is selected from

And the other is selected from hydrogen, halogen, hydroxyl, methyl, ethyl and methoxy.

10. The compound of any one of claims 1-3, 6, 8, 9, and pharmaceutically acceptable salts thereof, wherein,

selected from:

11. the compound of claim 4, and pharmaceutically acceptable salts thereof, wherein,

selected from:

12. the compound of claim 5, and pharmaceutically acceptable salts thereof, wherein,

selected from:

13. the compound of claim 7, and pharmaceutically acceptable salts thereof, wherein,

selected from:

14. a compound as described below and pharmaceutically acceptable salts thereof:

15. a pharmaceutical composition comprising as an active ingredient a compound according to any one of claims 1 to 14 and pharmaceutically acceptable salts, carriers or excipients thereof.

16. Use of a compound according to any one of claims 1 to 14, or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition according to claim 15, for the manufacture of a medicament for the prevention and/or treatment of diseases associated with the PD-1/PD-L1 signalling pathway.

17. The use according to claim 16, wherein the disease associated with the PD-1/PD-L1 signaling pathway is selected from the group consisting of cancer, infectious disease, and autoimmune disease.

18. The use according to claim 17, wherein the cancer is selected from the group consisting of lung cancer, skin cancer, hematological tumors, glioma, digestive system tumors, breast cancer, lymphoma, nervous system tumors, melanoma; the infectious diseases are selected from bacterial infection and viral infection; the autoimmune disease is selected from organ-specific, systemic autoimmune diseases; wherein the organ-specific autoimmune disease comprises chronic lymphocytic thyroiditis, hyperthyroidism, insulin-dependent diabetes mellitus, ulcerative colitis and acute idiopathic polyneuritis, and the systemic autoimmune disease comprises rheumatoid arthritis, systemic lupus erythematosus, systemic vasculitis and autoimmune hemolytic anemia.