A pd-l1 protein degrader with silicon-containing group as a hydrophobic tag, preparation method, pharmaceutical composition and application thereof

Abstract

The application belongs to the field of chemical drugs, and discloses a PD-L1 protein degrading agent with a silicon-containing group as a hydrophobic tag, a preparation method, a pharmaceutical composition and application thereof. The structure of the PD-L1 protein degrading agent with the silicon-containing group as the hydrophobic tag is shown in formula I, the linker is a saturated aliphatic chain, an unsaturated aliphatic chain, a connecting structure composed of an aromatic ring and a saturated aliphatic chain, or a connecting structure composed of an aromatic ring and an unsaturated aliphatic chain; and R is a specific silicon-containing group as the hydrophobic tag. The application obtains the PD-L1 protein degrading agent with the silicon-containing group as the hydrophobic tag, the preparation process is simple and easy to implement, the obtained PD-L1 protein degrading agent has high liver microsomal metabolic stability, has considerable oral bioavailability, shows high treatment efficiency in in-vivo experiments, has certain inhibition effect on the proliferation of various tumor cells, and is suitable for the development of cancer drugs such as leukemia.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of chemical drugs, and particularly relates to a PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag, a preparation method, a pharmaceutical composition and application thereof. BACKGROUND

[0002] Immune checkpoint blocking antibodies targeting the programmed death 1 (PD-1) / programmed cell death ligand 1 (PD-L1) interaction have achieved considerable clinical success, and to date, the US Food and Drug Administration (FDA) has approved several monoclonal antibodies that block the interaction between PD-1 and PD-L1 immune checkpoint proteins. In addition, some small molecules targeting the PD-1 / PD-L1 interaction have been recently reported, such as macrocyclic peptides, peptides, peptidomimetics and non-peptide structures. However, certain inherent defects of antibody drugs, such as immune-related adverse events, poor pharmacokinetic (PK) properties, poor tumor tissue penetration, high production cost and the like, hinder their more extensive clinical application. In addition, the cytoplasmic region of PD-L1 is involved in intracellular signaling that promotes tumor cell proliferation, which indicates that the modulation of PD-1 / PD-L1 interaction by inhibitors alone may not be sufficient to achieve the desired anti-tumor efficacy. Therefore, the development of PD-L1 degraders can be an effective strategy.

[0003] A hydrophobic tag (Hyt) bifunctional molecule is composed of a target protein ligand, a linker and a hydrophobic group. By connecting a large and hydrophobic group to a small molecule that can bind to the target, such a double-headed molecule, after binding to the target, will be mistakenly considered by the intracellular protein repair mechanism as a misfolded part of the target protein, and then it can be folded by chaperone proteins and degraded by proteasomes. The hydrophobic group in the Hyt molecule is often small in molecular weight, and thus can have higher solubility and drugability. The research and development of degraders based on hydrophobic tags is still in the exploratory stage. On the one hand, there are fewer reported hydrophobic tag fragments, and there is still a lot of room for optimization in terms of degradation activity and physicochemical properties. On the other hand, the exact degradation mechanism has not been clearly defined. Therefore, exploring more hydrophobic fragments with high activity and excellent physicochemical properties and clarifying their corresponding degradation mechanisms are crucial for the development of hydrophobic tag fragments based on clinical applications.

[0004] The hydrophobic fragments used in the currently reported hydrophobic tag degraders include adamantane, menthol, norbornene, Boc arginine, carborane, fluorenyl and the like. However, these conventional hydrophobic tag degraders have relatively low degradation effect, poor liver microsomal metabolic stability, poor solubility and are difficult to be orally administered, and thus are difficult to be used for further treatment and development in the clinic. There is a need for the development of new hydrophobic tag degraders with better liver microsomal stability and oral administration to meet the clinical needs. SUMMARY

[0005] The present application aims to solve the problems of the prior art, and provide a PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag, which has high liver microsomal metabolic stability and can be orally taken, and a preparation method, a pharmaceutical composition and an application thereof. Based on this, the first aspect of the present application provides a PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag, which has the structure shown in formula I:

[0006]

[0007] In the formula, the linker is a saturated aliphatic chain, an unsaturated aliphatic chain, a connecting structure composed of an aromatic ring and a saturated aliphatic chain, or a connecting structure composed of an aromatic ring and an unsaturated aliphatic chain; R is a trimethylsilyl group, a triethylsilyl group, a tri-n-propylsilyl group, a triisopropylsilyl group, an isopropyldimethylsilyl group, a tert-butyldimethylsilyl group, a tert-butyldiphenylsilyl group, a cyclohexyldimethylsilyl group, a vinyl dimethylsilyl group, a trimethoxysilyl group, a triethoxysilyl group, a phenylvinylmethylsilyl group, or a triphenylsilyl group.

[0008] The present application provides a PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag. In the bifunctional molecule, the silicon-containing group is used as a hydrophobic tag, and the BMS-37 parent nucleus is used as a target protein ligand, thereby obtaining a protein degrader capable of effectively degrading PD-L1. The PD-L1 protein degrader prepared by the present application can effectively induce the degradation of PD-L1 in the human acute myeloid leukemia cell line kasumi-1 in a dose-dependent and time-dependent manner, has considerable liver microsomal stability and bioavailability, and exhibits excellent anti-cancer effect in vivo.

[0009] In the formula, the linker is a saturated aliphatic chain, an unsaturated aliphatic chain, a connecting structure composed of an aromatic ring and a saturated aliphatic chain, or a connecting structure composed of an aromatic ring and an unsaturated aliphatic chain. By selecting different types and lengths of ideal linkers, the purpose of not affecting the binding of the two proteins in space and maintaining their binding can be achieved. Based on this, in some more preferred embodiments, the structure of the PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag is shown in formula II or formula III:

[0010]

[0011] In the formula, m and n are independently selected from integers in the range of 1-9.

[0012] When the structure of the PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag is as shown in Formula IV, it can effectively induce the degradation of PD-L1 in a human acute myeloid leukemia cell line kasumi-1 in a dose-dependent and time-dependent manner, has considerable liver microsomal stability and bioavailability, and exhibits excellent anti-leukemia effect in vivo.

[0013]

[0014] The second aspect of the present application provides a preparation method of the above-mentioned PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag, when the structure of the PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag is as shown in Formula II, the preparation method is shown in Route I; when the structure of the PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag is as shown in Formula III, the preparation method is shown in Route II.

[0015] Route I: tert-butyl diphenylchlorosilane (compound B) and azidoethanol (compound A) are reacted under the action of imidazole to obtain intermediate C, compound D and compound E are reacted by Mitsunobu reaction to obtain intermediate F, then reduced amination reaction with different length of alkyne amine to obtain intermediates G1-G5, and then Click reaction of intermediate C and intermediates G1-G5 to obtain final products 1-5.

[0016]

[0017] Route II: compound B and compounds H1-H4 are reacted under the action of imidazole to obtain intermediates I1-I4, then reduced amination reaction with compound F to obtain final products 6-9.

[0018]

[0019] The preparation method of the present application is simple in route, the raw materials used are cheap and easy to obtain, and the overall yield of the reaction is high.

[0020] The above-mentioned PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag or a pharmaceutically acceptable salt thereof can be used for preparing a medicament for treating related cancers with PD-L1 abnormalities. The above-mentioned related cancers include leukemia, melanoma, lung cancer, gastric cancer, breast cancer, colorectal cancer, and pancreatic cancer. More preferably, the related cancer is leukemia.

[0021] The third aspect of the present application provides a pharmaceutical composition comprising the PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag or a pharmaceutically acceptable salt thereof (or, the PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag or a pharmaceutically acceptable salt thereof as the main active ingredient). In some preferred embodiments, the above-mentioned pharmaceutical composition can further comprise at least one of an excipient, a solvent and a pharmaceutical carrier. Among them, the excipient is at least one of gum arabic, sugar syrup, lanolin and starch; there is no incompatibility with the main drug, no side effects, no influence on the curative effect, not easy to deform, dry, mold, insect damage at room temperature, harmless to the human body, no physiological effect, no chemical or physical action with the main drug, no influence on the content determination of the main drug. The solvent can be water, glycerol or ethanol.

[0022] The present application has the following beneficial effects: the present application obtains a PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag, the preparation process is simple and easy to operate, the obtained PD-L1 protein degrader has high liver microsomal metabolic stability, has considerable oral bioavailability, shows high treatment effect in in vivo experiments, has certain inhibitory effect on the proliferation of various tumor cells, and is suitable for the development of cancer drugs such as leukemia. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The figure shows the effect of compound 1 concentration-dependent degradation of PD-L1 in human acute myeloid leukemia cell line kasumi-1; (A) is a Western Blot diagram, (B) is a DC 50 FIG.

[0024] Figure 2 The figure shows the effect of compound 1 time-dependent degradation of PD-L1 in human acute myeloid leukemia cell line kasumi-1. DETAILED DESCRIPTION

[0025] The concept and technical effects of the present application will be described clearly and completely in combination with the embodiments and the drawings below, so as to fully understand the purpose, scheme and effect of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0026] Example 1

[0027] A PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag (denoted as compound 1-5), the structures of which are respectively as shown below:

[0028]

[0029] The structures of the intermediate compounds A, compound B, compound C, compound D, compound E, compound F, propynylamine, but-3-yn-1-amine, pent-4-yn-1-amine, hex-5-yn-1-amine, hept-6-yn-1-amine, compounds G1-G5 used are shown below, respectively:

[0030]

[0031]

[0032] The specific preparation method is:

[0033] 1) Preparation of compound C:

[0034] Compound A (174 mg, 2.00 mmol) was dissolved in dichloromethane (12 mL) under ice bath, compound B (825 mg, 3.00 mmol) and imidazole (408 mg, 6.00 mmol) were added, respectively, after 30 minutes, the ice bath was removed, and stirred at room temperature overnight, then the solid was filtered out, the remaining organic phase was dried with anhydrous sodium sulfate, concentrated, and then compound C was obtained by silica gel flash column chromatography (petroleum ether: ethyl acetate = 60:1).

[0035] Compound C was detected, and the detection results are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.72-7.66 (m, 4H), 7.41 (tt, J = 8.1, 5.7 Hz, 6H), 3.81 (dd, J = 5.5, 4.6 Hz, 2H), 3.29 (t, J = 5.0 Hz, 2H), 1.07 (s, 9H). 13 C NMR (100 MHz, CDCl3) δ 135.6, 133.1, 129.9, 127.8, 63.3, 53.2, 26.7, 19.1.

[0036] 2) Preparation of compound F:

[0037] Compound D (1.98 g, 10.0 mmol) and compound E (1.82 g, 10.0 mmol) were dissolved in tetrahydrofuran (30 mL) under ice bath, and triphenylphosphine (2.62 g, 10.0 mmol) was added, then diisopropyl azodicarboxylate (4.04 g, 20.0 mmol) was added dropwise to the reaction system, after the reaction was completed, it was diluted with water (50 mL) and extracted with ethyl acetate (3×50 mL), then the organic phase was combined and washed with saturated NaCl solution (50 mL), and the organic phase was dried with anhydrous sodium sulfate, concentrated, and the obtained crude product was purified by silica gel column chromatography (petroleum ether: ethyl acetate = 4:1) to obtain compound F.

[0038] Compound F was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.46 - 7.40 (m, 2 H), 7.40 - 7.32 (m, 5 H), 7.21 (ddt, J = 6.8, 2.2, 0.9 Hz, 1 H), 6.40 (s, 2 H), 5.15 (d, J = 0.9 Hz, 2 H), 3.89 (s, 6 H), 2.30 (s, 3 H).

[0039] 3) Preparation of compounds G1-G5:

[0040] Preparation of compound G1:

[0041] Compound F (362 mg, 1.00 mmol), acetic acid (60.1 mg, 1.00 mmol) were dissolved in dichloromethane (12 mL) under ice bath, and propargylamine (82.5 mg, 1.50 mmol) was added to the reaction system, after one hour, sodium cyanoborohydride (126 mg, 2.00 mmol) was slowly added, and then the reaction system was reacted at room temperature overnight, after the reaction was completed, it was diluted with water (10 mL) and extracted with dichloromethane (3 x 10 mL), then the organic phases were combined and dried with anhydrous sodium sulfate, and concentrated, and the obtained crude product was purified by silica gel column chromatography (petroleum ether: ethyl acetate = 2: 1) to obtain compound G1.

[0042] Compound G1 was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.46 - 7.40 (m, 2 H), 7.40 - 7.32 (m, 5 H), 7.21 (ddt, J = 6.8, 2.2, 0.9 Hz, 1 H), 6.40 (s, 2 H), 5.15 (d, J = 0.9 Hz, 2 H), 3.89 (s, 6 H), 2.30 (s, 3 H). 13 C NMR (100 MHz, CDC13) δ 161.7, 159.8, 143.2, 141.9, 134.8, 134.6, 130.5, 129.5, 128.4, 128.2, 127.0, 125.8, 101.6, 91.3, 76.3, 75.4, 69.5, 55.9, 39.8, 36.1, 16.3.

[0043] Preparation of compound G2:

[0044] Compound G2 was obtained by replacing compound propargylamine with compound but-3-yn-1-amine (104 mg, 1.50 mmol) according to the same method as that for preparing compound G1.

[0045] Compound G2 was tested and the results of the test are as follows:1 H NMR (400 MHz, CDC13) δ 7.52 - 7.20 (m, 8H), 6.27 (s, 2H), 5.10 (s, 2H), 4.26 (s, 2H), 3.87 (s, 6H), 3.04 (t, J = 7.3 Hz, 2H), 2.72 (d, J = 7.4 Hz, 2H), 2.27 (s, 3H), 2.09 (s, 1H). 13 C NMR (100 MHz, CDC13) δ 176.7, 162.1, 159.8, 143.1, 141.8, 134.6, 134.6, 130.5, 129.4, 128.4, 128.2, 127.0, 125.7, 99.4, 91.2, 79.1, 71.7, 69.5, 55.9, 44.6, 40.5, 23.0, 16.5, 16.3.

[0046] Preparation of compound G3:

[0047] Compound G3 was obtained by replacing compound propargylamine with compound pent-4-yn-1-amine (125 mg, 1.50 mmol) according to the same method as for preparing compound G1.

[0048] Compound G3 was detected, and the detection results are as follows: 1 H NMR (400 MHz, CDC13) δ 7.52 - 7.20 (m, 8H), 6.27 (s, 2H), 5.10 (s, 2H), 4.26 (s, 2H), 3.87 (s, 6H), 3.04 (t, J = 7.3 Hz, 2H), 2.72 (d, J = 7.4 Hz, 2H), 2.27 (s, 3H), 2.09 (s, 1H). 13 C NMR (100 MHz, CDC13) δ 176.7, 162.1, 159.8, 143.1, 141.8, 134.6, 134.6, 130.5, 129.4, 128.4, 128.2, 127.0, 125.7, 99.4, 91.2, 79.1, 71.7, 69.5, 55.9, 44.6, 40.5, 23.0, 16.5, 16.3.

[0049] Preparation of compound G4:

[0050] Compound G4 was obtained by replacing compound propargylamine with compound hex-5-yn-1-amine (146 mg, 1.50 mmol) according to the same method as for preparing compound G1.

[0051] Compound G4 was detected, and the detection results are as follows: 1H NMR (400 MHz, CDC13) δ 7.48 - 7.40 (m, 2H), 7.40 - 7.31 (m, 5H), 7.21 (ddt, J = 6.8, 2.1, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.00 (d, J = 5.8 Hz, 2H), 3.90 (s, 6H), 2.76 (dt, J = 5.0, 4.3 Hz, 2H), 2.66 - 2.55 (m, 1H), 2.43 (td, J = 5.7, 3.0 Hz, 2H), 2.30 (s, 3H), 2.05 (t, J = 3.0 Hz, 1H), 1.67 - 1.43 (m, 4H).

[0052] Preparation of compound G5:

[0053] Compound hept-6-yn-1-amine (167 mg, 1.50 mmol) was used instead of compound propargylamine according to the same method as for the preparation of compound G1 to give compound G5.

[0054] Compound G5 was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.48 - 7.40 (m, 2H), 7.40 - 7.31 (m, 5H), 7.21 (ddt, J = 6.8, 2.1, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.00 (d, J = 5.8 Hz, 2H), 3.90 (s, 6H), 2.76 (dt, J = 5.0, 4.3 Hz, 2H), 2.66 - 2.55 (m, 1H), 2.43 (td, J = 5.7, 3.0 Hz, 2H), 2.30 (s, 3H), 2.05 (t, J = 3.0 Hz, 1H), 1.67 - 1.43 (m, 4H).

[0055] 4) Preparation of compound 1-5:

[0056] Preparation of compound 1:

[0057] G1 (92.3 mg, 0.230 mmol) and compound C (91.1 mg, 0.280 mmol) were dissolved in a t-BuOH / H20 (5 mL, 1:1) mixed solvent, CuS04·5H20 (18.6 mg, 0.116 mmol), sodium L-ascorbate (38.4 mg, 0.194 mmol) were added, and the reaction was allowed to proceed at room temperature overnight. After the completion of the reaction, CuS04·5H20 was removed by filtration, and the filtrate was concentrated in vacuo and separated by silica gel flash column chromatography (dichloromethane:methanol = 30:1) to obtain compound 1.

[0058] Compound 1 was tested and the results of the testing are as follows: 1 H NMR (400 MHz, CDC13) δ 7.64 - 7.17 (m, 19H), 6.25 (d, J = 11.2 Hz, 2H), 5.10 (d, J = 13.3 Hz, 2H), 4.56 - 4.38 (m, 2H), 4.26 (d, J = 18.6 Hz, 1H), 4.18 - 3.94 (m, 5H), 3.81 (d, J = 9.2 Hz, 6H), 2.28 (d, J = 7.4 Hz, 3H), 1.00 (s, 9H). 13 C NMR (100 MHz, CDC13) δ 143.1, 141.9, 135.5, 135.5, 135.0, 134.8, 134.5, 132.7, 130.5, 130.4, 130.1, 130.0, 129.4, 128.4, 128.4, 128.1, 128.0, 127.9, 127.0, 126.9, 125.7, 125.7, 91.3, 69.5, 62.5, 55.9, 29.8, 26.9, 26.8, 19.2, 16.3.

[0059] Preparation of Compound 2:

[0060] Compound G2 (95.6 mg, 0.230 mmol) was replaced for compound Gl following the same procedure as for the preparation of compound 1 to obtain compound 2.

[0061] Compound 2 was tested and the results of the testing are as follows: 1 H NMR (400 MHz, CDC13) δ 7.64 - 7.17 (m, 19H), 6.25 (d, J = 11.2 Hz, 2H), 5.10 (d, J = 13.3 Hz, 2H), 4.56 - 4.38 (m, 2H), 4.26 (d, J = 18.6 Hz, 1H), 4.18 - 3.94 (m, 5H), 3.81 (d, J = 9.2 Hz, 6H), 2.28 (d, J = 7.4 Hz, 3H), 1.00 (s, 9H). 13 C NMR (100 MHz, CDC13) δ 143.1, 141.9, 135.5, 135.5, 135.0, 134.8, 134.5, 132.7, 130.5, 130.4, 130.1, 130.0, 129.4, 128.4, 128.4, 128.1, 128.0, 127.9, 127.0, 126.9, 125.7, 125.7, 91.3, 69.5, 62.5, 55.9, 29.8, 26.9, 26.8, 19.2, 16.3.

[0062] Preparation of Compound 3:

[0063] Compound G1 was replaced with compound G3 (98.8 mg, 0.230 mmol) according to the same method as for the preparation of compound 1 to obtain compound 3.

[0064] Compound 3 was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.56 - 7.25 (m, 19H), 6.23 (s, 2H), 5.08 (s, 2H), 4.41 (t, J = 5.3 Hz, 2H), 4.17 (s, 2H), 3.97 (t, J = 5.2 Hz, 2H), 3.84 (s, 6H), 2.93 (t, J = 6.9 Hz, 2H), 2.81 (t, J = 7.0 Hz, 2H), 2.26 (s, 3H), 2.18 (t, J = 6.9 Hz, 2H), 1.00 (s, 9H). 13 C NMR (100 MHz, CDC13) δ 160.0, 143.2, 141.9, 135.5, 134.8, 134.7, 132.7, 130.6, 130.1, 129.5, 128.5, 128.2, 128.0, 127.0, 125.8, 91.2, 69.5, 62.7, 56.0, 52.5, 29.8, 26.8, 23.1, 19.2, 16.4.

[0065] Preparation of compound 4:

[0066] Compound G1 was replaced with compound G4 (102 mg, 0.230 mmol) according to the same method as for the preparation of compound 1 to obtain compound 4.

[0067] Compound 4 was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.56 - 7.25 (m, 19H), 6.23 (s, 2H), 5.08 (s, 2H), 4.41 (t, J = 5.3 Hz, 2H), 4.17 (s, 2H), 3.97 (t, J = 5.2 Hz, 2H), 3.84 (s, 6H), 2.93 (t, J = 6.9 Hz, 2H), 2.81 (t, J = 7.0 Hz, 2H), 2.26 (s, 3H), 2.18 (t, J = 6.9 Hz, 2H), 1.00 (s, 9H).

[0068] Preparation of compound 5:

[0069] Compound G1 was replaced with compound G5 (105 mg, 0.230 mmol) according to the same method as that for preparing compound 1 to obtain compound 5.

[0070] Compound 5 was detected, and the detection results are as follows: 1 H NMR (400 MHz, CDC13) δ 7.65 - 7.58 (m, 4H), 7.48 (s, 1H), 7.46 - 7.40 (m, 2H), 7.40 - 7.32 (m, 11H), 7.21 (ddt, J = 6.8, 2.2, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.31 (t, J = 4.1 Hz, 2H), 4.18 (t, J = 4.1 Hz, 2H), 4.00 (d, J = 5.8 Hz, 2H), 3.90 (s, 6H), 2.80 - 2.66 (m, 4H), 2.60 (tt, J = 5.7, 4.8 Hz, 1H), 2.30 (s, 3H), 1.80 (p, J = 8.0 Hz, 2H), 1.62 - 1.50 (m, 2H), 1.41 (pd, J = 7.5, 0.9 Hz, 2H), 1.03 (s, 9H).

[0071] Example 2

[0072] A PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag (denoted as compounds 6-9), the structures of which are respectively as shown below:

[0073]

[0074] The structures of the intermediate compounds H1-H4, compound B, compounds I1-I4, and compound F used are respectively as shown below:

[0075]

[0076] The specific preparation method is as follows:

[0077] 1) Preparation of compounds I1-I4:

[0078] Preparation of compound I1:

[0079] Compound H1 (150 mg, 2.00 mmol) was dissolved in dichloromethane (12 mL) under ice bath, compound B (825 mg, 3.00 mmol) and imidazole (408 mg, 6.00 mmol) were added respectively, after 30 minutes, the ice bath was removed, stirred overnight at room temperature, the solid was filtered out, the remaining organic phase was dried using anhydrous sodium sulfate, concentrated and then compound 11 was obtained by silica gel flash column chromatography (petroleum ether: ethyl acetate = 20: 1).

[0080] Compound 11 was detected, and the detection results were as follows: 1 H NMR (400 MHz, CDC13) δ 7.70 - 7.50 (m, 4H), 7.45 - 7.29 (m, 6H), 3.73 (t, J = 5.7 Hz, 2H), 2.93 (tt, J = 6.4, 5.5 Hz, 2H), 1.74 (p, J = 5.6 Hz, 2H), 1.48 (t, J = 6.4 Hz, 2H), 1.03 (s, 9H).

[0081] Preparation of compound 12:

[0082] Compound H1 was replaced by compound H2 (178 mg, 1.50 mmol) according to the same method for preparing compound 11 to obtain compound 12.

[0083] Compound 12 was detected, and the detection results were as follows: 1 H NMR (400 MHz, CDC13) δ 7.79 - 7.47 (m, 4H), 7.46 - 7.23 (m, 6H), 3.77 - 3.55 (m, 2H), 2.95 - 2.61 (m, 2H), 1.81 (t, J = 6.5 Hz, 2H), 1.70 - 1.40 (m, 4H), 1.03 (s, 9H).

[0084] Preparation of compound 13:

[0085] Compound H1 was replaced by compound H3 (206 mg, 1.50 mmol) according to the same method for preparing compound 11 to obtain compound 13.

[0086] Compound 13 was detected, and the detection results were as follows: 1 H NMR (400 MHz, CDC13) δ 7.80 - 7.49 (m, 4H), 7.53 - 7.21 (m, 6H), 3.67 (t, J = 6.0 Hz, 2H), 2.66 (tt, J = 6.5, 5.2 Hz, 2H), 1.78 (t, J = 6.5 Hz, 2H), 1.61 - 1.26 (m, 6H), 1.03 (s, 9H).

[0087] Preparation of compound I4:

[0088] Compound H4 (234 mg, 1.50 mmol) was replaced for compound H1 following the same procedure as for the preparation of compound I1 to obtain compound I4.

[0089] Compound I4 was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.68 - 7.51 (m, 4H), 7.47 - 7.10 (m, 6H), 3.68 (t, J = 6.0 Hz, 2H), 2.67 (tt, J = 6.5, 5.2 Hz, 2H), 1.78 (t, J = 6.5 Hz, 2H), 1.68 - 1.25 (m, 8H), 1.03 (s, 9H).

[0090] 2) Preparation of compounds 6-9:

[0091] Preparation of compound 6:

[0092] Compound F (181 mg, 0.500 mmol), acetic acid (30.0 mg, 0.500 mmol) were dissolved in dichloromethane (5 mL) under ice bath, compound I1 (235 mg, 0.750 mmol) was added to the reaction system, after one hour, sodium cyanoborohydride (63.2 mg, 1.00 mmol) was slowly added, then the reaction system was reacted at room temperature overnight, after the reaction was completed, it was diluted with water (8 mL) and extracted with dichloromethane (3 x 8 mL), then the organic phases were combined and dried over anhydrous sodium sulfate, concentrated, and the obtained crude product was purified by silica gel column chromatography (petroleum ether: ethyl acetate = 5: 1) to obtain compound 6.

[0093] Compound 6 was tested and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.68 - 7.51 (m, 4H), 7.47 - 7.10 (m, 6H), 3.68 (t, J = 6.0 Hz, 2H), 2.67 (tt, J = 6.5, 5.2 Hz, 2H), 1.78 (t, J = 6.5 Hz, 2H), 1.68 - 1.25 (m, 8H), 1.03 (s, 9H).

[0094] Preparation of compound 7:

[0095] Compound 7 was obtained by replacing compound II with compound I2 (246 mg, 0.750 mmol) according to the same method as for the preparation of compound 6.

[0096] Compound 7 was detected, and the detection results are as follows: 1 H NMR (400 MHz, CDC13) δ 7.68 - 7.57 (m, 4H), 7.46 - 7.40 (m, 2H), 7.40 - 7.32 (m, 11H), 7.21 (ddt, J = 6.8, 2.2, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.00 (d, J = 5.9 Hz, 2H), 3.90 (s, 6H), 3.71 (t, J = 5.7 Hz, 2H), 2.75 (q, J = 5.1 Hz, 2H), 2.60 (tt, J = 5.7, 4.8 Hz, 1H), 2.30 (s, 3H), 1.74 - 1.56 (m, 4H), 1.03 (s, 9H).

[0097] Preparation of compound 8:

[0098] Compound 8 was obtained by replacing compound II with compound I3 (256 mg, 0.750 mmol) according to the same method as for the preparation of compound 6.

[0099] Compound 8 was detected, and the detection results are as follows: 1 H NMR (400 MHz, CDC13) δ 7.68 - 7.57 (m, 4H), 7.46 - 7.40 (m, 2H), 7.40 - 7.32 (m, 11H), 7.21 (ddt, J = 6.8, 2.2, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.00 (d, J = 5.9 Hz, 2H), 3.90 (s, 6H), 3.71 (t, J = 5.7 Hz, 2H), 2.75 (q, J = 5.1 Hz, 2H), 2.60 (tt, J = 5.7, 4.8 Hz, 1H), 2.30 (s, 3H), 1.74 - 1.56 (m, 4H), 1.03 (s, 9H).

[0100] Preparation of compound 9:

[0101] Compound 9 was obtained by replacing compound II with compound I4 (267 mg, 0.750 mmol) according to the same method as for the preparation of compound 6.

[0102] Compound 9 was tested and the results are as follows: 1 H NMR (400 MHz, CDC13) δ 7.68 - 7.57 (m, 4H), 7.50 - 7.41 (m, 2H), 7.41 - 7.32 (m, 11H), 7.21 (ddt, J = 6.8, 2.2, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.00 (d, J = 5.8 Hz, 2H), 3.90 (s, 6H), 3.68 (t, J = 6.0 Hz, 2H), 2.72 (q, J = 5.2 Hz, 2H), 2.60 (tt, J = 5.7, 4.8 Hz, 1H), 2.30 (s, 3H), 1.65 - 1.47 (m, 4H), 1.41 - 1.29 (m, 4H), 1.03 (s, 9H).

[0103] Comparative Example 1

[0104] Compound 10 is a non-silicon-containing group hydrophobic tag comparative example. Its structure is shown below:

[0105]

[0106] Its synthetic route is as follows:

[0107]

[0108] The structures of the intermediate compounds J, compound K, compound L, and compound G1 used are as follows:

[0109]

[0110] The specific preparation method is as follows:

[0111] 1) Preparation of compound L:

[0112] Compound K (456 mg, 3.00 mmol) was dissolved in tetrahydrofuran (15 mL) at 0°C, followed by the addition of sodium hydride (180 mg, 4.50 mmol, the content of sodium hydride used was 60%), after stirring at this temperature for ten minutes, compound J (1.45 g, 6.00 mmol) was added, and the reaction was carried out at room temperature overnight. After the reaction was completed, ethyl acetate (40 mL) was added, and the organic phase was washed with saturated brine (20 mL). The organic phase was dried using anhydrous sodium sulfate, concentrated, and the obtained crude product was purified by silica gel column chromatography (petroleum ether: ethyl acetate = 20: 1) to obtain compound L.

[0113] Compound L was tested and the results are as follows: 1H NMR (400 MHz, CDC13) δ 3.68 (t, J = 6.8 Hz, 2H), 3.41 (t, J = 6.7 Hz, 2H), 2.32 (dt, J = 10.8, 5.3 Hz, 3H), 2.11 (d, J = 5.1 Hz, 6H), 1.70 (t, J = 5.6 Hz, 6H).

[0114] 2) Preparation of compound 10:

[0115] Compound 10 was obtained according to the same method as for the preparation of compound 1, replacing compound C with compound L (62.0 mg, 0.280 mmol).

[0116] Compound 10 was tested, and the results of the test are as follows: 1 H NMR (400 MHz, CDC13) δ 7.57 (s, 1H), 7.46 - 7.40 (m, 2H), 7.40 - 7.33 (m, 5H), 7.21 (ddt, J = 6.8, 2.1, 0.9 Hz, 1H), 6.28 (s, 2H), 5.15 (d, J = 0.9 Hz, 2H), 4.33 (t, J = 4.0 Hz, 2H), 4.31 - 4.24 (m, 1H), 4.14 (dd, J = 10.4, 5.9 Hz, 4H), 3.90 (s, 6H), 3.80 (t, J = 4.0 Hz, 2H), 2.30 (s, 3H), 2.11 (hept, J = 5.5 Hz, 3H), 1.81 - 1.63 (m, 12H).

[0117] Compound performance test

[0118] 1) Western blotting was applied to evaluate the ability of the PD-L1 protein degraders with silicon-containing groups as the hydrophobic tag (PD-L1 protein degraders 1-9 prepared in Examples 1-2) and the PD-L1 protein degrader with non-silicon-containing groups as the hydrophobic tag comparative example (PD-L1 protein degrader 10 prepared in Comparative Example 1) to degrade PD-L1 in human acute myeloid leukemia cell line kasumi-1, and the concentration of each compound was 0.1 μM and 1 μM. The degradation efficiency results are shown in Table 1, and the IC 50 The evaluation was performed, and the results are shown in Table 1.

[0119] Table 1 PD-L1 degradation efficiency of compounds in human acute myeloid leukemia cell line kasumi-1 and IC 50

[0120]

[0121]

[0122] From Table 1, it can be seen that each compound has a certain ability to degrade PD-L1, and is better than the PD-L1 protein degrading agent comparative compound 10 with a non-silicon-containing group as a hydrophobic tag. Compound 1 is the most excellent, and compound 1 is selected for further degradation effect evaluation. Human acute myeloid leukemia cell line kasumi-1 is selected, and eight concentration gradients of 0, 0.15, 0.3, 0.6, 1.25, 2.5, 5, and 10 μM are set to determine whether the compound can degrade PD-L1 in a concentration-dependent manner. The results are shown in Table 2. Figure 1 The results show that compound 1 can degrade PD-L1 in human acute myeloid leukemia cell line kasumi-1 in a concentration-dependent manner, and the degradation DC 50 is 0.51 μM.

[0123] Human acute myeloid leukemia cell line kasumi-1 is selected, and six time gradients of 0, 3, 6, 9, 12, and 24 h are set to determine whether the compound can degrade PD-L1 in a time-dependent manner. The results are shown in Table 3. Figure 2 The results show that compound 1 can degrade PD-L1 in human acute myeloid leukemia cell line kasumi-1 in a time-dependent manner.

[0124] 2) The liver microsomal metabolic stability of compound 1 is evaluated. Compound 10 with a non-silicon-containing group as a hydrophobic tag is used as a comparison, and Diclofenac is used as a positive control.

[0125] The specific method for evaluating the stability of liver microsomal metabolism is as follows: the liver microsomes are taken out from the -80°C refrigerator and placed on a 37°C water bath constant temperature oscillator for pre-warming incubation for 3 min, and then thawed for use. Then a certain amount of NADPH is weighed, and a proper amount of magnesium chloride solution is added to dissolve into a 2 mM solution for use. The incubation system mixture solution (without NADPH) is prepared according to the composition ratio of the experimental incubation system (3 mM MgCl2-PB solution, 1 μM test compound, 0.5 mg / mL liver microsomes), and is divided into 40 μL / tube. The 0 min sample is added with 240 μL of internal standard working precipitant, and then 40 μL of NADPH solution (40 μL of magnesium chloride solution is added to the negative control group), and the other samples are added with 40 μL of NADPH solution to start the reaction (40 μL of magnesium chloride solution is added to the negative control group), and then incubated at 37°C for 5 min, 15 min, 30 min and 60 min, and then 240 μL of internal standard precipitant is added, and 40 μL of NADPH solution is added to the positive control group to start the reaction, and then incubated at 37°C for 5 min and 15 min, and then 240 μL of internal standard precipitant is added. All the samples are vortexed and centrifuged to take 150 μL of supernatant, and then vortexed after adding 150 μL of water, and then subjected to LC-MS / MS sample analysis. It is found by analysis and calculation that compound 1 shows clearance efficiency in two species of humans and mice, and is significantly stable in the PD-L1 protein degradation agent comparative example 10 with a non-silicon group as a hydrophobic tag, and the results are shown in Table 2.

[0126] Table 2: Stability of liver microsomal metabolism

[0127]

[0128]

[0129] The oral bioavailability of compound 1 is evaluated.

[0130] The specific method for evaluating the oral bioavailability is as follows: after the rats are fasted overnight, three are administered by gavage (10 mg / kg), and three are administered by tail vein (1 mg / kg), and then blood is taken at 5 min, 15 min, 30 min, 1 h, 2 h, 4 h, 6 h and 8 h, and then placed in pre-heparin sodium tubes, and then vortexed to mix the blood and heparin sodium, and then centrifuged (4°C, 3000 rpm, 10 min) to obtain plasma, and then 50 μL of plasma sample is taken, and then 50 μL of diluent (50% methanol / water) and 250 μL of methanol precipitant are added, and then vortexed and centrifuged (4°C, 12000 rpm, 10 min), and then the supernatant is filtered and stored for LC-MS / MS detection. The results (Table 3) show that compound 1 has good oral bioavailability of 14.6%.

[0131] Table 3: Kinetic parameters

[0132]

[0133] From Table 2 and the evaluation results of oral bioavailability, it can be seen that the present application is optimized in terms of hydrophobic tag type and linker type, etc., and the selected compound 1 can exert higher metabolic stability and in vivo bioavailability.

[0134] 3) In vivo pharmacodynamics PD experiment was evaluated in a xenograft model, and the mice received a single oral dose of compound 1 (10 mg / kg). The mice were euthanized at the designated time points (0 hours, 6 hours, 12 hours, 24 hours, 48 hours and 72 hours) after oral administration, and the tumor tissues were harvested for Western blotting analysis. The data are shown in Table 4, and the results show that compound 1 significantly reduces PD-L1 expression within 6 hours, and the effect lasts up to 48 hours. These findings indicate that the degrading agent 1 can maintain the PD-L1 degradation effect in vivo for a long time.

[0135] Table 4 PD data

[0136]

[0137] 4) In vivo pharmacodynamic evaluation of compound 1, human acute myeloid leukemia cell line kasumi-1 cells were selected to establish a mouse model.

[0138] Subcutaneous tumor-bearing model: Kasumi-1 cell suspension was mixed with Matrigel and injected subcutaneously into NU / NU mice. When the average diameter of the tumor reached 3 mm, it was randomly divided into a control group (5), an oral administration of compound 1 group 1 (5mpk, 5, daily administration), and an oral administration of compound 1 group 2 (10mpk, 5, daily administration). After 18 days, the body weight of the mice in the administration groups and the control group showed no significant fluctuations, and the mice showed no significant abnormalities, indicating that compound 1 was safe. The tumor weight and tumor volume of the mice in the administration groups were significantly lower than those in the control group, and the tumor inhibition rate ((1-tumor weight of administration group / tumor weight of control group)*100%) is shown in Table 5. The results show that compound 1 has a strong in vivo therapeutic effect.

[0139] Table 5 TGI of Kasumi-1 cell xenograft model

[0140]

[0141] The above is only a preferred embodiment of the present application, and the present application is not limited to the above-described embodiments, as long as the same means achieve the technical effects of the present application, it should belong to the protection scope of the present application. The technical solutions and / or embodiments within the protection scope of the present application can have various modifications and changes.

Claims

1. A PD-L1 protein degrader using a silicon-containing group as a hydrophobic tag, characterized in that: Its structure is shown in Formula II or Formula III: Formula II; Formula III; wherein m and n are independently selected from integers ranging from 1 to 9.

2. The PD-L1 protein degrader with a silicon-containing group as a hydrophobic tag according to claim 1, characterized in that Its structure is shown in Formula IV: Formula IV.

3. Use of the PD-L1 protein degrader comprising a silicon-containing group as a hydrophobic tag or a pharmaceutically acceptable salt thereof according to claim 1 or 2 in the preparation of a medicament for treating a cancer associated with PD-L1 abnormality, wherein the cancer is leukemia.

4. A pharmaceutical composition, characterized in that The PD-L1 protein degrader comprising a silicon-containing group as a hydrophobic tag according to claim 1 or 2, or a pharmaceutically acceptable salt thereof.

5. The pharmaceutical composition according to claim 4, characterized in that Pharmaceutically acceptable excipients are also included.

6. The pharmaceutical composition according to claim 5, characterized in that The excipient is at least one of gum arabic, syrup, lanolin and starch.

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