Targeted platelet-derived growth factor receptor beta inhibitor, radioactive probe and application

Abstract

The invention relates to a platelet-derived growth factor receptor beta (PDGFR beta) targeting inhibitor, a radioactive probe and application, and belongs to the field of nuclear medicine imaging agents and nuclide radiotherapy agents. The inhibitor is at least one of compounds shown in a formula I, and the radioactive probe is at least one of compounds shown in a formula II. The PDGFR beta targeting radioactive probe provided by the invention can specifically target a PDGFR beta high-expression tumor, and has good tumor uptake and rapid in-vivo metabolism properties. The targeted PDGFRbeta radioactive probe provided by the invention has a relatively good tumor ratio, can be rapidly metabolized and discharged out of a body through the kidney, and has an important clinical application value for early precise diagnosis and targeted radioactive treatment of PDGFRbeta positive tumors and screening of people benefitting an anti-angiogenesis treatment strategy.

Description

Technical Field

[0001] The invention relates to an inhibitor targeting platelet-derived growth factor receptor beta (PDGFRβ), a radioactive probe and application thereof, and belongs to the field of nuclear medicine imaging agents and radionuclide radiotherapy agents. Background Art

[0002] Platelet-derived growth factor receptor β (PDGFRβ) is a transmembrane receptor tyrosine kinase that can bind to platelet-derived growth factor family members such as PDGF-BB and PDGF-DD, initiate intercellular information transmission, increase mitotic activity, anti-apoptotic activity, actin reorganization and cell migration, and play an important role in angiogenesis. PDGFRβ is lowly expressed in most normal cells, but highly expressed in different tumors, and is associated with tumor progression (tumor cell migration, metastasis and proliferation, and angiogenesis), making it a potential target for the development of tumor imaging agents.

[0003] The tumor vascular system is an important factor affecting the efficacy of tumor treatment. Tumors not only obtain oxygen and nutrients from the host through new tumor blood vessels, but also continuously transmit metastatic cells to the host through new blood vessels, while releasing tumorigenic cytokines and angiogenic factors, which ultimately lead to tumor infiltration and migration. Tumor new blood vessels are different from normal blood vessels in structure and physiology. The tumor vascular system of most solid tumors develops rapidly, with large endothelial gaps, abnormal or missing basement membranes, abnormal pericyte morphology, and strong vascular permeability. Targeted therapy for receptors related to tumor angiogenesis has become a new method for tumor treatment in recent years. Overexpression of PDGFRβ is associated with abnormal angiogenesis, and therefore has become a potential marker for anti-angiogenic treatment strategies in vascular-rich tumor diseases such as liver cancer, glioblastoma, lung cancer, breast cancer, prostate cancer, and colorectal cancer.

[0004] Nuclear medicine positron emission tomography / computed tomography (PET / CT) is a radionuclide imaging technology that uses radioactive probes to non-invasively visualize tumor lesions and microenvironments at the molecular level. It has the advantages of real-time, dynamic, quantitative, high sensitivity, and high resolution. PET / CT uses radioactive probes to play multiple roles in early diagnosis, efficacy evaluation, and prognosis of tumors. At the same time, radioactive probes can use radioactive therapeutic nuclides to target and kill tumors, and have excellent clinical treatment value.

[0005] There have been many reports on the development of radioactive probes targeting PDGFRβ. Although the reported radioactive probes targeting PDGFRβ can image tumors, they have certain disadvantages: high nonspecific uptake in normal tissues (especially kidneys), resulting in high radioactive dose burden and damage; most probes are antibody probes, which have the disadvantage of high immunogenicity and cannot be used repeatedly. By modifying the structure of the compound, the in vivo metabolic properties of the probe can be improved and the nonspecific uptake of normal tissues can be reduced; the use of small molecule probes can overcome the shortcomings of antibody probes: compared with antibody probes, small molecule probes have the advantages of small molecular weight, good tumor permeability, fast non-target uptake and clearance, and low immunogenicity, and are the preferred choice for radioactive probe design. However, due to the great difficulty in the development of small molecule probes compared with peptide / antibody probes, there have been no reports of small molecule radioactive probes targeting PDGFRβ at home and abroad so far.

[0006] Therefore, taking PDGFRβ as the target, a specific small molecule inhibitor and radioactive probe targeting PDGFRβ are provided, and with the help of nuclear medicine PET / CT technology, early and accurate diagnosis, efficacy evaluation and prognosis assessment of patients with hypervascular tumor diseases can be achieved, as well as screening of people who benefit from anti-angiogenic treatment strategies. At the same time, radioactive probes are used to perform radionuclide targeted therapy on patients who cannot undergo surgical resection, which is of great value for the clinical diagnosis and treatment of hypervascular tumors (liver cancer, glioblastoma, lung cancer, breast cancer, prostate cancer and colorectal cancer). Summary of the invention

[0007] The purpose of the present invention is to provide a specific small molecule inhibitor and radioactive probe targeting PDGFRβ. For vascularized tumors (liver cancer, glioblastoma, lung cancer, breast cancer, prostate cancer and colorectal cancer) with high expression of PDGFRβ, the targeted PDGFRβ radioactive probe of the present invention is combined with PET / CT to achieve early accurate diagnosis of the disease, efficacy evaluation and prognosis evaluation, and screen the population benefiting from the anti-angiogenic treatment strategy; for patients with tumors that cannot be surgically removed, the targeted PDGFRβ small molecule inhibitor of the present invention is used to chelate radioactive therapeutic nuclides to achieve targeted radiotherapy, thereby improving the therapeutic effect. The present invention constructs a small molecule inhibitor and radioactive probe with high selectivity and high affinity for PDGFRβ by constructing a core targeting group and changing different connecting groups. It is verified by experiments that the small molecule targeted PDGFRβ inhibitor and radioactive probe constructed by the present invention have good specific targeted uptake and rapid in vivo metabolic properties for tumors with high expression of PDGFRβ, low nonspecific uptake in normal tissues, and rapid metabolism and excretion from the body through the kidneys, thereby obtaining a good tumor-to-body ratio.

[0008] To achieve the above object, the first aspect of the present invention provides an inhibitor targeting PDGFRβ, wherein the inhibitor is at least one of the compounds shown in Formula I:

[0009]

[0010] Wherein, Chelator is a bifunctional chelating agent structure selected from any one of the following:

[0011]

[0012]

[0013]

[0014] L1 is Wherein, n1 is 0 or 1; L2 is a linking group selected from any one of the following:

[0015]

[0016] Wherein, n2 is an integer from 0 to 8;

[0017] L3 Wherein, n3 is 0 or 1.

[0018] Specifically, the inhibitor is preferably selected from one of the following inhibitors 1-3:

[0019]

[0020] The second aspect of the present invention provides a radioactive probe targeting PDGFRβ, wherein the radioactive probe is at least one of the compounds represented by Formula II:

[0021]

[0022] Wherein, the Chelate portion is a structure formed by chelating a radionuclide with a bifunctional chelating agent, and is selected from any one of the following:

[0023]

[0024]

[0025]

[0026] Wherein, M is a radionuclide, and the radionuclide is a diagnostic radionuclide or a therapeutic radionuclide; the diagnostic radionuclide is Al 18 F. 68 Ga,64 Cu, 44 Sc, 89 Zr, 86 Y. 90 Y. 99m Tc and 111 In at least one, the therapeutic radionuclide is 67 Cu, 177 Lu, 225 Ac, 211 At 212 Pb, 212 Bi, 213 Bi, 161 Tb, 111 In, 153 Sm, 186 Re and 188 At least one of Re;

[0027] L1 is Where n1 is 0 or 1;

[0028] L2 is a linking group selected from any of the following:

[0029]

[0030] Wherein, n2 is an integer from 0 to 8;

[0031] L3 Wherein, n3 is 0 or 1.

[0032] Specifically, the radioactive probe is preferably selected from one of the following radioactive probes 4-9:

[0033]

[0034]

[0035] The third aspect of the present invention provides the use of the above-mentioned radioactive probe in the preparation of a radioactive imaging diagnostic reagent or a radionuclide therapeutic reagent. The radioactive imaging diagnostic reagent is preferably an early detection reagent, efficacy evaluation reagent, prognosis judgment reagent, or anti-angiogenic therapy benefit screening reagent for PDGFRβ-high-expressing tumors; the radionuclide therapeutic reagent is preferably a therapeutic reagent for PDGFRβ-high-expressing tumors; the tumor is preferably a highly vascular tumor: liver cancer, glioblastoma, lung cancer, breast cancer, prostate cancer, and colorectal cancer.

[0036] The present invention provides inhibitors and radioactive probes containing a core targeting group and different linking groups, wherein the core targeting group is preferably an N-terminal group that selectively binds to PDGFRβ. 2-(4-(4-(5-aminopentyl)piperazin-1-yl)-3-methoxyphenyl)-N 4 -(1H-indazol-6-yl)-5-methylpyrimidine-2,4-diamine, the linking group is preferably The inhibitor and the radioactive probe both exhibit high targeting specificity and high binding affinity to PDGFRβ.

[0037] Beneficial effects:

[0038] The targeted PDGFRβ radioactive probe of the present invention has excellent radiochemical yield and radiochemical purity, as well as excellent in vitro stability, and has good specific targeted uptake and rapid in vivo metabolic properties for tumors with high PDGFRβ expression. The PDGFRβ radioactive probe provided by the present invention has low nonspecific uptake in normal tissues, is rapidly metabolized and excreted from the body by the kidneys, and obtains a good tumor-to-body ratio, and has important application value for early accurate diagnosis of hypervascular tumors (liver cancer, glioblastoma, lung cancer, breast cancer, prostate cancer, and colorectal cancer), screening of populations benefiting from anti-angiogenic therapy, and radioactive targeted therapy.

[0039] The present invention is described in detail below through the accompanying drawings and specific embodiments, but it is not intended to limit the protection scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1-1 to Figure 1-3 The mass spectra of inhibitors 1, 2 and 3 synthesized in Example 1 of the present invention;

[0041] Figure 2-1 to Figure 2-4 [ 68 Ga]Ga-1,[ 177 Radioactive HPLC and radioactive TLC diagrams of the labeling reaction solution of Lu]Lu-1;

[0042] Figure 3-1 to Figure 3-4 [ 68 Ga]Ga-2,[ 177 Radioactive HPLC and radioactive TLC diagrams of the labeling reaction solution of Lu]Lu-2;

[0043] Figure 4-1 to Figure 4-4 [ 68 Ga]Ga-3,[ 177 Radioactive HPLC and radioactive TLC images of the labeling reaction solution of Lu]Lu-3;

[0044] Figure 5 In Example 5 of the present invention, [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[68 HPLC profiles of the radioactivity of Ga]Ga-3 incubated in saline or mouse serum at 37°C for different time periods;

[0045] Figure 6 In Example 6 of the present invention, in the absence / presence of different PDGFRβ inhibitors, glioblastoma cells (U87MG cells, PDGFRβ positive) in vitro were tested for [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 uptake diagram (n=4);

[0046] Figure 7 In Example 7 of the present invention, [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Uptake of Ga]Ga-3 in tumor and normal tissues of U87MG tumor-bearing (PDGFRβ-positive) nude mice (n=4). DETAILED DESCRIPTION

[0047] Unless otherwise specified, the raw materials and reagents mentioned in the examples of the present invention are conventional raw materials and reagents available on the market, the test methods used are conventional methods used in the art, and the equipment and devices used are conventional equipment and devices in the art.

[0048] Example 1: Preparation and characterization of PDGFRβ-targeted inhibitors 1, 2, and 3

[0049] Step 1: Preparation and characterization of targeted PDGFRβ inhibitor 1:

[0050] The synthetic route is as follows:

[0051]

[0052] The specific steps include:

[0053] (1) Synthesis of Compound 1:

[0054] Benzyl chlorocarbonate (680 mg, 4 mmol) was dissolved in ethyl acetate (15 mL), cesium carbonate (1630 mg, 5 mmol) was added, and the mixture was stirred at room temperature for 10 minutes. Tert-butyl 4-(4-amino-2-methoxyphenyl)piperazine-1-carboxylate (1228 mg, 4 mmol) dissolved in ethyl acetate (30 mL) was added dropwise to the solution. The reaction solution was stirred under reflux at 80° C. for 17 hours, filtered with diatomaceous earth, and evaporated under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography (dichloromethane / methanol=20 / 1, v / v) to obtain brown-yellow oily compound 1 (1320 mg, 2.99 mmol) with a yield of 74.8%.

[0055] Structural confirmation of compound 1: HRMS C 24 H 32 N3O5[M+H] + Theoretical molecular weight 442.2336, measured molecular weight 442.2322, Δ = -3.2741ppm;

[0056] (2) Synthesis of Compound 2:

[0057] Compound 1 (1320 mg, 2.99 mmol) was dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 30 minutes, and then evaporated under reduced pressure to remove the solvent. The compound 1 was dissolved in ethyl acetate (20 mL), and cesium carbonate (1304 mg, 4 mmol) was added. After stirring at room temperature for 10 minutes, tert-butyl (5-bromopentyl)carbamate (795 mg, 3 mmol) dissolved in ethyl acetate (30 mL) was added dropwise to the above solution. The reaction solution was refluxed and stirred at 80° C. for 48 hours, filtered with diatomaceous earth, and evaporated under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography (dichloromethane / methanol=20 / 1, v / v) to obtain a purple oily compound 2 (1415 mg, 2.69 mmol) with a yield of 89.7%.

[0058] Structural confirmation of compound 2: HRMS C 29 H 43 N4O5[M+H] + Theoretical molecular weight 527.3227, measured molecular weight 527.3211, Δ = -3.2188ppm;

[0059] (3) Synthesis of Compound 3:

[0060] Compound 2 (38 mg, 0.072 mmol) was dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 30 minutes, and then evaporated under reduced pressure to remove the solvent to obtain a brown oil; 5-(tert-butoxy)-5-oxo-4-(4,7,10-tris(2-(tert-butoxy)-2-oxoethyl)-1,4,7,10-tetraazacyclododec-1-yl)pentanoic acid (50 mg, 0.071 mmol) was dissolved in ultra-dry N,N-dimethylformamide (2 mL), stirred in an ice-water bath, 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU, 66 mg, 0.17 mmol) was added, and N,N '-Diisopropylethylamine (DIPEA, 54 mg, 0.42 mmol), after stirring in an ice-water bath for 30 minutes, the above brown oil dissolved in ultra-dry N,N-dimethylformamide (2 mL) was added dropwise, the reaction solution was stirred in an ice-water bath for 3 hours, extracted with ethyl acetate (30 mL×3), the organic phase was collected, washed with saturated brine (30 mL×2), the organic phase was collected, dried over anhydrous sodium sulfate, filtered, anhydrous sodium sulfate was removed, the filtrate was evaporated under reduced pressure to remove the solvent, and purified by silica gel column chromatography (dichloromethane / methanol=40 / 1, v / v) to obtain yellow oily compound 3 (59.6 mg, 0.054 mmol), yield: 75.7%;

[0061] Structural confirmation of compound 3: HRMS C 59 H 97 N8O 12 [M+H] + Theoretical molecular weight 1109.722, measured molecular weight 1109.7197, Δ = -2.1158ppm;

[0062] (4) Synthesis of PDGFRβ-targeted inhibitor 1:

[0063] Compound 3 (10.2 mg, 0.0092 mmol) was dissolved in methanol (5 mL), palladium carbon (0.5 mg, 0.0047 mmol) was added, and the mixture was stirred at room temperature for 1 hour under a hydrogen atmosphere. The mixture was filtered through celite and evaporated under reduced pressure to remove the solvent. The residue was dissolved in methanol (12 mL), and N-(2-chloro-5-methylpyrimidin-4-yl)-1H-indazole-6-amine (30 mg, 0.116 mmol) and trifluoroacetic acid (0.48 mL) were added. The mixture was stirred under reflux at 80° C. under a nitrogen atmosphere for 60 hours. The solvent was removed by rotary evaporation under reduced pressure. The residue was purified by high performance liquid chromatography (phase A: 0.1% trifluoroacetic acid in water, phase B: 0.1% trifluoroacetic acid in acetonitrile, 0-15 minutes: 0%-30% B, 15-17 minutes: 30%-0% B; 17-20 minutes: 0% B) yellow floccules were obtained, which were dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 8 hours, and then evaporated under reduced pressure to remove the solvent. The residue was purified by high performance liquid chromatography (phase A: 0.1% trifluoroacetic acid in water, phase B: 0.1% trifluoroacetic acid in acetonitrile, 0-15 minutes: 0%-30% B, 15-17 minutes: 30%-0% B; 17-20 minutes: 0% B) to obtain colorless flocculent inhibitor 1 (2.02 mg, 0.0021 mmol), yield: 22.6%, purity: >95%;

[0064] Structural confirmation of PDGFRβ-targeted inhibitor 1: HRMS C 47 H 68 N 13 O 10 [M+H] + Theoretical molecular weight 974.5206, measured molecular weight 974.5194, Δ = -1.2956ppm;

[0065] like Figure 1-1 Shown is the high-resolution mass spectrum of the targeted PDGFRβ inhibitor 1;

[0066] Step 2: Preparation and characterization of targeted PDGFRβ inhibitor 2:

[0067] The synthetic route is as follows:

[0068]

[0069] The specific steps include:

[0070] (1) Synthesis of compound 4:

[0071] Compound 2 (275 mg, 0.65 mmol) was dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 30 minutes, and then evaporated under reduced pressure to remove the solvent to obtain a brown oil; 2,2-dimethyl-4-oxo-3,8,11,14-tetraoxa-5-azaheptadecan-17-oic acid (208 mg, 0.65 mmol) was dissolved in ultra-dry N,N-dimethylformamide (2 mL), stirred in an ice-water bath, 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU, 591 mg, 1.55 mmol) was added, and N,N'-diisopropylethylamine (DIPEA) was added dropwise. , 482 mg, 3.73 mmol), stirred in an ice-water bath for 30 minutes, and then the brown oil dissolved in ultra-dry N,N-dimethylformamide (2 mL) was added dropwise. The reaction solution was stirred in an ice-water bath for 4 hours, extracted with ethyl acetate (30 mL×3), and the organic phase was collected. The organic phase was washed with saturated brine (30 mL×2), and the organic phase was collected. Anhydrous sodium sulfate was added to dry the organic phase, and the organic phase was filtered to remove the anhydrous sodium sulfate. The filtrate was evaporated under reduced pressure to remove the solvent, and then purified by silica gel column chromatography (dichloromethane / methanol=30 / 1, v / v) to obtain yellow oily compound 4 (303.6 mg, 0.416 mmol), with a yield of 64.0%;

[0072] Structural confirmation of compound 4: HRMS C 38 H 60 N5O9[M+H] + Theoretical molecular weight 730.4385, measured molecular weight 730.4369, Δ = -2.2666ppm;

[0073] (2) Synthesis of Compound 5:

[0074] Compound 4 (52 mg, 0.071 mmol) was dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 30 minutes, and then evaporated under reduced pressure to remove the solvent to obtain a brown oil; 5-(tert-butoxy)-5-oxo-4-(4,7,10-tris(2-(tert-butoxy)-2-oxoethyl)-1,4,7,10-tetraazacyclododec-1-yl)pentanoic acid (50 mg, 0.071 mmol) was dissolved in ultra-dry N,N-dimethylformamide (2 mL), stirred in an ice-water bath, 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU, 66 mg, 0.17 mmol) was added, and N,N' was added dropwise. -diisopropylethylamine (DIPEA, 54 mg, 0.42 mmol), after stirring in an ice-water bath for 30 minutes, the above brown oil dissolved in ultra-dry N,N-dimethylformamide (2 mL) was added dropwise, the reaction solution was stirred in an ice-water bath for 7.5 hours, extracted with ethyl acetate (30 mL×3), the organic phase was collected, washed with saturated brine (30 mL×2), the organic phase was collected, dried with anhydrous sodium sulfate, filtered, anhydrous sodium sulfate was removed, the filtrate was evaporated under reduced pressure to remove the solvent, and purified by silica gel column chromatography (dichloromethane / methanol=30 / 1, v / v) to obtain yellow oily compound 5 (78.7 mg, 0.060 mmol), yield: 84.5%;

[0075] Structure confirmation of compound 5: HRMS C 68 H 114 N9O 16 [M+H] + Theoretical molecular weight 1312.8378, measured molecular weight 1312.8405, Δ = 2.0518ppm;

[0076] (3) Synthesis of PDGFRβ-targeted inhibitor 2:

[0077] Compound 5 (63.5 mg, 0.048 mmol) was dissolved in methanol (5 mL), palladium carbon (2.55 mg, 0.024 mmol) was added, and the mixture was stirred at room temperature for 1 hour under a hydrogen atmosphere. The mixture was filtered through celite and evaporated under reduced pressure to remove the solvent. The residue was dissolved in methanol (12 mL), and N-(2-chloro-5-methylpyrimidin-4-yl)-1H-indazole-6-amine (30 mg, 0.116 mmol) and trifluoroacetic acid (0.48 mL) were added. The mixture was stirred under reflux at 80° C. under a nitrogen atmosphere for 60 hours. The solvent was removed by rotary evaporation under reduced pressure. The residue was purified by high performance liquid chromatography (phase A: 0.1% trifluoroacetic acid in water, phase B: 0.1% trifluoroacetic acid in acetonitrile, 0-15 minutes: 0%-30% B, 15-17 minutes: 30%-0% B; 17-20 minutes: 0% B) yellow floccules were obtained, which were dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 8 hours, and then evaporated under reduced pressure to remove the solvent. The residue was purified by high performance liquid chromatography (phase A: 0.1% trifluoroacetic acid in water, phase B: 0.1% trifluoroacetic acid in acetonitrile, 0-15 minutes: 0%-30% B, 15-17 minutes: 30%-0% B; 17-20 minutes: 0% B) to obtain colorless flocculent inhibitor 2 (17.1 mg, 0.0145 mmol), yield: 30.3%, purity: >95%;

[0078] Structural confirmation of PDGFRβ-targeted inhibitor 2: HRMS C 56 H 84 N 14 O 14 [M+H] + Theoretical molecular weight 1177.6364, measured molecular weight 1177.6339, Δ = -2.1406ppm;

[0079] like Figure 1-2 Shown is the high-resolution mass spectrum of the targeted PDGFRβ inhibitor 2;

[0080] Step 3: Preparation and characterization of targeted PDGFRβ inhibitor 3:

[0081] The synthetic route is as follows:

[0082]

[0083] The specific steps include:

[0084] (1) Synthesis of Compound 6:

[0085] Compound 2 (158 mg, 0.3 mmol) was dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 30 minutes, and then evaporated under reduced pressure to remove the solvent to obtain a brown oil; 2,2-dimethyl-4-oxo-3,8,11,14,17,20,23-heptyloxy-5-azahexacan-26-oic acid (136 mg, 0.3 mmol) was dissolved in ultra-dry N,N-dimethylformamide (2 mL), stirred in an ice-water bath, 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU, 273.6 mg, 0.72 mmol) was added, and N,N'-diisopropylethylamine (D IPEA, 223 mg, 1.725 mmol), stirred in an ice-water bath for 30 minutes, then the brown oil dissolved in ultra-dry N,N-dimethylformamide (2 mL) was added dropwise, the reaction solution was stirred in an ice-water bath for 4 hours, extracted with ethyl acetate (30 mL×3), the organic phase was collected, washed with saturated brine (30 mL×2), the organic phase was collected, dried with anhydrous sodium sulfate, filtered, anhydrous sodium sulfate was removed, the filtrate was evaporated under reduced pressure to remove the solvent, and purified by silica gel column chromatography (dichloromethane / methanol=20 / 1, v / v) to obtain yellow oily compound 6 (221.6 mg, 0.257 mmol), yield: 85.7%;

[0086] Structure confirmation of compound 6: HRMS C 44 H 72 N5O 12 [M+H] + Theoretical molecular weight 862.5172, measured molecular weight 862.5151, Δ = -2.4347ppm;

[0087] (2) Synthesis of Compound 7:

[0088] Compound 6 (74 mg, 0.086 mmol) was dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 30 minutes, and then evaporated under reduced pressure to remove the solvent to obtain a brown oil; 5-(tert-butoxy)-5-oxo-4-(4,7,10-tris(2-(tert-butoxy)-2-oxoethyl)-1,4,7,10-tetraazacyclododec-1-yl)pentanoic acid (60 mg, 0.086 mmol) was dissolved in ultra-dry N,N-dimethylformamide (2 mL), stirred in an ice-water bath, 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU, 98 mg, 0.26 mmol) was added, and N,N' was added dropwise. -diisopropylethylamine (DIPEA, 90 mg, 0.70 mmol), after stirring in an ice-water bath for 30 minutes, the brown oil dissolved in ultra-dry N,N-dimethylformamide (2 mL) was added dropwise, the reaction solution was stirred in an ice-water bath for 8.5 hours, extracted with ethyl acetate (30 mL×3), the organic phase was collected, washed with saturated brine (30 mL×2), the organic phase was collected, dried over anhydrous sodium sulfate, filtered, anhydrous sodium sulfate was removed, the filtrate was evaporated under reduced pressure to remove the solvent, and purified by silica gel column chromatography (dichloromethane / methanol=30 / 1, v / v) to obtain yellow oily compound 7 (83.9 mg, 0.058 mmol), yield: 67.6%;

[0089] Structural confirmation of compound 7: HRMS C 74 H 125 N9O 19 [M+H] + Theoretical molecular weight 1444.9164, measured molecular weight 1444.9158, Δ = -0.4503ppm;

[0090] (3) Synthesis of PDGFRβ-targeted inhibitor 3:

[0091] Compound 7 (69.5 mg, 0.048 mmol) was dissolved in methanol (5 mL), palladium carbon (2.55 mg, 0.024 mmol) was added, and the mixture was stirred at room temperature for 1 hour under a hydrogen atmosphere. The mixture was filtered through celite, and the solvent was removed by rotary evaporation under reduced pressure. The residue was dissolved in methanol (12 mL), and N-(2-chloro-5-methylpyrimidin-4-yl)-1H-indazole-6-amine (30 mg, 0.116 mmol) and trifluoroacetic acid (0.48 mL) were added. The mixture was stirred under reflux at 80° C. under a nitrogen atmosphere for 60 hours. The solvent was removed by rotary evaporation under reduced pressure. The residue was purified by high performance liquid chromatography (phase A: 0.1% trifluoroacetic acid in water, phase B: 0.1% trifluoroacetic acid in acetonitrile, 0-15 minutes: 0%-30% B, 15-17 minutes: 30%-0% B; 17-20 minutes: 0% B) yellow floccules were obtained, which were dissolved in trifluoroacetic acid (5 mL), stirred at room temperature for 8 hours, and then evaporated under reduced pressure to remove the solvent. The residue was purified by high performance liquid chromatography (phase A: 0.1% trifluoroacetic acid in water, phase B: 0.1% trifluoroacetic acid in acetonitrile, 0-15 minutes: 0%-30% B, 15-17 minutes: 30%-0% B; 17-20 minutes: 0% B) to obtain colorless flocculent inhibitor 3 (8.89 mg, 0.0068 mmol), yield: 14.2%, purity: >95%;

[0092] Structural confirmation of PDGFRβ-targeted inhibitor 3: HRMS C 62 H 97 N 14 O 17 [M+H] + Theoretical molecular weight 1309.715, measured molecular weight 1309.7174, Δ = 1.7826ppm;

[0093] like Figure 1-3 Shown is the high-resolution mass spectrum of PDGFRβ-targeted inhibitor 3.

[0094] Example 2: Radioactive probe targeting PDGFRβ 68 Ga]Ga-1,[ 177 Preparation and quality control of Lu-1 Step 1: Radioactive probe targeting PDGFRβ [ 68 Preparation and Quality Control of Ga]Ga-1

[0095] 68 The Ga radiolabeling route is as follows:

[0096]

[0097] The specific steps include:

[0098] Dissolve inhibitor 1 in dimethyl sulfoxide to prepare a 1 μg / μL labeled precursor solution. Take the labeled precursor solution (14 μL, 14 μg, 14 nmol) in a 10 mL vial and add sodium acetate buffer solution (80 μL). Use high-purity hydrochloric acid solution (6 mL, 0.6 M) to elute the germanium-68 / gallium-68 generator (iThemba) to obtain [ 68 Ga]GaCl3 hydrochloric acid solution, take [ 68 Ga]GaCl3 hydrochloric acid solution (0.3 mL, 2.5 mCi) was added to the above mixture, the reaction solution was mixed, heated at 95°C for 20 min and then cooled to room temperature. The radiochemical purity of the product was determined using a high performance liquid chromatograph with a radioactivity detector and a TLC scanner to obtain [ 68 Ga]Ga-1;

[0099] like Figure 2-1 As shown, it is [ 68 The radioactive HPLC chart of the reaction solution labeled with Ga]Ga-1 shows that [ 68 The retention time of Ga]Ga-1 was 9.42 min, and the radiochemical purity was ≥95%, which was 95.3%;

[0100] like Figure 2-2 As shown, it is [ 68 The radioactive TLC diagram of the reaction solution labeled with Ga]Ga-1 shows that [ 68 Ga]Ga-1R f is 0.6-1.0, radiochemical purity ≥95%, which is 95.0%;

[0101] Step 2: Targeting PDGFRβ radioactive probe 177 Preparation and quality control of Lu]Lu-1

[0102] 177 The Lu radiolabeling route is as follows:

[0103]

[0104] The specific steps include:

[0105] Dissolve inhibitor 1 in dimethyl sulfoxide to prepare a 1 μg / μL labeled precursor solution. Take the labeled precursor solution (14 μL, 14 μg, 14 nmol) in a 10 mL vial, add sodium acetate buffer solution (15 μL) and [ 177Lu]LuCl3 hydrochloric acid solution (0.4mL, 1mCi, 0.04M hydrochloric acid), the reaction solution was mixed, heated at 95℃ for 20min and then cooled to room temperature. The radiochemical purity of the product was determined using a high performance liquid chromatograph with a radioactivity detector and a TLC scanner to obtain [ 177 Lu]Lu-1;

[0106] like Figure 2-3 As shown, it is [ 177 The radioactive HPLC chart of the labeling reaction solution of Lu]Lu-1 shows that [ 177 Lu]Lu-1 had a retention time of 9.45 min and a radiochemical purity of ≥95%, which was 96.0%;

[0107] like Figure 2-4 As shown, it is [ 177 The radioactive TLC chart of the labeling reaction solution of Lu]Lu-1 shows that [ 177 Lu] Lu-1 R f The purity of the catalyst was 0.7-1.0, and the radiochemical purity was ≥95%, which was 97.0%.

[0108] Example 3: Radioactive probe targeting PDGFRβ 68 Ga]Ga-2,[ 177 Preparation and quality control of Lu-2 Step 1: Radioactive probe targeting PDGFRβ [ 68 Preparation and Quality Control of Ga]Ga-2

[0109] 68 The Ga radiolabeling route is as follows:

[0110]

[0111] The specific steps include:

[0112] Dissolve inhibitor 2 in dimethyl sulfoxide to prepare a 1 μg / μL labeling precursor solution. Take the labeling precursor solution (17 μL, 17 μg, 14 nmol) in a 10 mL vial and add sodium acetate buffer solution (80 μL). Use high-purity hydrochloric acid solution (6 mL, 0.6 M) to elute the germanium-68 / gallium-68 generator (iThemba) to obtain [ 68 Ga]GaCl3 hydrochloric acid solution, take [ 68Ga]GaCl3 hydrochloric acid solution (0.3 mL, 2.5 mCi) was added to the above mixture, the reaction solution was mixed, heated at 95°C for 20 min and then cooled to room temperature. The radiochemical purity of the product was determined using a high performance liquid chromatograph with a radioactivity detector and a TLC scanner to obtain [ 68 Ga]Ga-2;

[0113] like Figure 3-1 As shown, it is [ 68 The radioactive HPLC chart of the reaction solution labeled with Ga]Ga-2 shows that [ 68 The retention time of Ga]Ga-2 was 9.68 min, and the radiochemical purity was ≥95%, which was 97.3%;

[0114] like Figure 3-2 As shown, it is [ 68 The radioactive TLC diagram of the reaction solution labeled with Ga]Ga-2 shows that [ 68 Ga]Ga-2R f is 0.6-1.0, radiochemical purity ≥95%, which is 98.4%;

[0115] Step 2: Targeting PDGFRβ radioactive probe 177 Preparation and quality control of Lu]Lu-2

[0116] 177 The Lu radiolabeling route is as follows:

[0117]

[0118] The specific steps include:

[0119] Dissolve inhibitor 2 in dimethyl sulfoxide to prepare a 1 μg / μL labeled precursor solution. Take the labeled precursor solution (17 μL, 17 μg, 14 nmol) in a 10 mL vial, add sodium acetate buffer solution (15 μL) and [ 177 Lu]LuCl3 hydrochloric acid solution (0.4mL, 1mCi, 0.04M hydrochloric acid), the reaction solution was mixed, heated at 95℃ for 20min and then cooled to room temperature. The radiochemical purity of the product was determined using a high performance liquid chromatograph with a radioactivity detector and a TLC scanner to obtain [ 177 Lu]Lu-2;

[0120] like Figure 3-3 As shown, it is [ 177 The radioactive HPLC chart of the labeling reaction solution of Lu]Lu-2 shows that [ 177Lu]Lu-2 had a retention time of 9.55 min and a radiochemical purity of ≥95%, which was 95.9%;

[0121] like Figure 3-4 As shown, it is [ 177 The radioactive TLC chart of the labeling reaction solution of Lu]Lu-2 shows that [ 177 Lu] Lu-2 R f The purity of the catalyst was 0.6-1.0, and the radiochemical purity was ≥95%, which was 97.6%.

[0122] Example 4: Radioactive probe targeting PDGFRβ 68 Ga]Ga-3,[ 177 Preparation and quality control of Lu-3 Step 1: Radioactive probe targeting PDGFRβ [ 68 Preparation and Quality Control of Ga]Ga-3

[0123] 68 The Ga radiolabeling route is as follows:

[0124]

[0125] The specific steps include:

[0126] Dissolve inhibitor 3 in dimethyl sulfoxide to prepare a 1 μg / μL labeling precursor solution. Take the labeling precursor solution (19 μL, 19 μg, 14 nmol) in a 10 mL vial and add sodium acetate buffer solution (80 μL). Use high-purity hydrochloric acid solution (6 mL, 0.6 M) to elute the germanium-68 / gallium-68 generator (iThemba) to obtain [ 68 Ga]GaCl3 hydrochloric acid solution, take [ 68 Ga]GaCl3 hydrochloric acid solution (0.3 mL, 2.5 mCi) was added to the above mixture, the reaction solution was mixed, heated at 95°C for 20 min and then cooled to room temperature. The radiochemical purity of the product was determined using a high performance liquid chromatograph with a radioactivity detector and a TLC scanner to obtain [ 68 Ga]Ga-3;

[0127] like Figure 4-1 As shown, it is [ 68 The radioactive HPLC chart of the reaction solution labeled with Ga]Ga-3 shows that [ 68 The retention time of Ga]Ga-3 was 9.54 min, and the radiochemical purity was ≥95%, which was 96.9%;

[0128] like Figure 4-2 As shown, it is [ 68The radioactive TLC diagram of the reaction solution labeled with Ga]Ga-3 shows that [ 68 Ga]Ga-3R f is 0.6-1.0, radiochemical purity ≥95%, 97.7%;

[0129] Step 2: Targeting PDGFRβ radioactive probe 177 Preparation and quality control of Lu]Lu-3

[0130] 177 The Lu radiolabeling route is as follows:

[0131]

[0132] The specific steps include:

[0133] Dissolve inhibitor 3 in dimethyl sulfoxide to prepare a 1 μg / μL labeled precursor solution. Take the labeled precursor solution (19 μL, 19 μg, 14 nmol) in a 10 mL vial, add sodium acetate buffer solution (15 μL) and [ 177 Lu]LuCl3 hydrochloric acid solution (0.4mL, 1mCi, 0.04M hydrochloric acid), the reaction solution was mixed, heated at 95℃ for 20min and then cooled to room temperature. The radiochemical purity of the product was determined using a high performance liquid chromatograph with a radioactivity detector and a TLC scanner to obtain [ 177 Lu]Lu-3;

[0134] like Figure 4-3 As shown, it is [ 177 The radioactive HPLC chart of the labeling reaction solution of Lu]Lu-3 shows that [ 177 Lu]Lu-3 had a retention time of 9.74 min and a radiochemical purity of ≥95%, which was 97.8%;

[0135] like Figure 4-4 As shown, it is [ 177 The radioactive TLC chart of the labeling reaction solution of Lu]Lu-3 shows that [ 177 Lu] Lu-3 R f The purity of the catalyst was 0.6-1.0, and the radiochemical purity was ≥95%, which was 98.4%.

[0136] Example 5: Targeting PDGFRβ 68 Ga labeled radioactive probe [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Study on the in vitro stability of Ga]Ga-3

[0137] The radiochemical purity of [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 (100 μL) was added to physiological saline (900 μL), incubated at 37°C, and samples were taken at 1 hour and 2 hours, respectively, and the radiochemical purity was detected using a high performance liquid chromatograph with a radioactivity detector; [Ga]Ga-3 with a radiochemical purity greater than 95% was added to the 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 (150 μL) was added to mouse serum (450 μL), incubated at 37°C, samples (100 μL) were taken at 1 and 2 h, acetonitrile (200 μL) was added to precipitate the protein, centrifuged at 14000 rpm for 5 min, the supernatant was taken, and the radiochemical purity was detected using a high performance liquid chromatograph with a radioactivity detector;

[0138] like Figure 5 As shown, in Example 5 of the present invention, [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 The radioactive HPLC graph of Ga]Ga-3 incubated in saline or mouse serum at 37°C for different time periods shows that [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 After incubation in saline or mouse serum at 37°C for 2 h, the retention time of Ga]Ga-3 did not change and the radiochemical purity remained ≥95%, indicating that [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 both have excellent in vitro stability.

[0139] Example 6: Targeting PDGFRβ 68 Ga labeled radioactive probe [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Study on the specific binding ability of Ga]Ga-3 with PDGFRβ protein

[0140] The radiochemical purity was greater than 95%. 68 Ga]Ga-1 or [ 68 Ga]Ga-2 or [ 68Ga]Ga-3 was added to serum-free DMEM culture medium to prepare a drug incubation solution of 28pmol / 1.5μCi / mL. Glioblastoma cells (U87MG cells, PDGFRβ positive) were cultured with serum-free DMEM culture medium for 10 6 cells / mL of cell suspension; for the uptake group, 1 mL of drug incubation solution and 1 mL of cell suspension were mixed in an EP tube and incubated at 37°C for 30 minutes; for the inhibition group, 1 mL of drug incubation solution (containing 8.4 μM PDGFRβ inhibitor (PDGFR-IN-1 or CP-673451)) and 1 mL of cell suspension were mixed in an EP tube and incubated at 37°C for 30 minutes; after the incubation, the EP tube was centrifuged at 1000 rpm / min for 4 minutes, the liquid was discarded, 1 mL of ice-cold PBS was added, vortexed and mixed, centrifuged at 1000 rpm / min for 4 minutes, the liquid was discarded, and the washing was repeated again; the EP tube was inserted into the soft tube, and the radioactivity count of the soft tube was determined using a γ counter; the total drug uptake by the cells was calculated as: radioactivity count of the soft tube / radioactivity count of 1 mL of drug incubation solution per tube × 100%, the unit is %ID / 10 6 cells;

[0141] like Figure 6 As shown in Example 6 of the present invention, in the absence / presence of different PDGFRβ inhibitors, U87MG cells (PDGFRβ positive) in vitro [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 The figure shows the uptake of Ga]Ga-3 (n=4). It can be seen that in the absence of PDGFRβ inhibitor, U87MG cells with high expression of PDGFRβ were significantly inhibited by [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 The uptake of Ga]Ga-3 is high, indicating that [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 have excellent binding affinity with PDGFRβ protein; in the presence of excessive PDGFRβ inhibitors (PDGFR-IN-1 or CP-673451), U87MG cells are sensitive to [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 The uptake of Ga]Ga-3 was significantly inhibited (P less than 0.001), indicating that [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68The binding of Ga]Ga-3 to U87MG cells is a specific binding to PDGFRβ protein. 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 has good specific binding ability with PDGFRβ protein.

[0142] Example 7: Targeting PDGFRβ 68 Ga labeled radioactive probe [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Study on the Biodistribution of Ga]Ga-3

[0143] Female BALB / c nude mice (4 weeks old) were implanted with 10 6 U87MG cells (PDGFRβ positive) were raised in a specific pathogen-free environment for 4-5 weeks. After the tumor diameter reached 8-10 mm, they were used for the experiment. U87MG tumor-bearing nude mice were randomly divided into 4 / group; 68 Ga]Ga-1 or [ 68 Ga]Ga-2 or [ 68 Ga]Ga-3 was added to physiological saline to prepare a radioactive preparation of 1.4nmol / 75μCi / 150μL. The radioactive preparation (150μL) was injected into U87MG tumor-bearing nude mice via the tail vein. The nude mice were anesthetized and killed at 10 minutes, 30 minutes, and 60 minutes. The tumor and other tissues of interest were removed and weighed. The radioactivity count was measured using a γ counter, and the percentage of injected dose per gram of tissue (%ID / g) was calculated. The radioactive probe [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 In vivo PDGFRβ targeting, tumor uptake, and tissue distribution metabolism of Ga]Ga-3;

[0144] like Figure 7 As shown, in Example 7 of the present invention, [ 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 The uptake diagram of the radioactive probe [Ga]Ga-3 in the tumor and normal tissues of U87MG tumor-bearing (PDGFRβ-positive) nude mice (n=4). 68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 Ga]Ga-3 both rapidly target PDGFRβ-highly expressed tumors, with excellent tumor uptake. Except for the excretory organs (kidneys), the tumor is the site of the highest radioactivity concentration; the radioactive probe [68 Ga]Ga-1,[ 68 Ga]Ga-2,[ 68 The uptake of Ga]Ga-3 in normal tissues is low and they are metabolized and excreted from the body relatively quickly through the kidneys.

[0145] The above experimental results indicate that the PDGFRβ-targeted radioactive probe provided by the present invention can specifically target tumors with high PDGFRβ expression, has good tumor uptake and rapid in vivo metabolic properties, can be rapidly metabolized and excreted from the body through the kidneys, and achieves a good tumor-to-target ratio.

[0146] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. An inhibitor targeting platelet-derived growth factor receptor β, characterized in that: The inhibitor is at least one of the compounds shown in Formula I: Wherein, Chelator is a bifunctional chelating agent structure selected from any one of the following: L1 is Where n1 is 0 or 1; L2 is a linking group selected from any of the following: Wherein, n2 is an integer from 0 to 8; L3 Wherein, n3 is 0 or 1.

2. A radioactive probe targeting platelet-derived growth factor receptor β, characterized in that: The radioactive probe is at least one of the compounds shown in Formula II: Wherein, the Chelate portion is a structure formed by chelating a radionuclide with a bifunctional chelating agent, and is selected from any one of the following: Wherein, M is the radionuclide; L1 is Where n1 is 0 or 1; L2 is a linking group selected from any of the following: Wherein, n2 is an integer from 0 to 8; L3 Wherein, n3 is 0 or 1.

3. The radioactive probe targeting platelet-derived growth factor receptor β according to claim 2, wherein: M is a radionuclide, which is a diagnostic radionuclide or a therapeutic radionuclide; the diagnostic radionuclide is Al 18 F. 68 Ga, 64 Cu, 44 Sc, 89 Zr, 86 Y. 90 Y. 99m Tc and 111 In at least one, the therapeutic radionuclide is 67 Cu, 177 Lu, 225 Ac, 211 At 212 Pb, 212 Bi, 213 Bi, 161 Tb, 111 In, 153 Sm, 186 Re and 188 At least one of Re.

4. The inhibitor targeting platelet-derived growth factor receptor β according to claim 1, wherein the inhibitor is selected from one of the following inhibitors 1-3:

5. The radioactive probe targeting platelet-derived growth factor receptor β according to claims 2 and 3, wherein the radioactive probe is selected from one of the following radioactive probes 4-9:

6. Use of the radioactive probe described in any one of claims 2, 3 and 5 in the preparation of a radioactive imaging diagnostic reagent or a radionuclide therapeutic reagent, wherein the radioactive imaging diagnostic reagent is preferably an early detection reagent, efficacy evaluation reagent, prognosis judgment reagent or anti-angiogenic therapy beneficiary population screening reagent for tumors with high platelet-derived growth factor receptor β expression; the radionuclide therapeutic reagent is preferably a therapeutic reagent for tumors with high platelet-derived growth factor receptor β expression; the tumor is preferably a highly vascular tumor: liver cancer, glioblastoma, lung cancer, breast cancer, prostate cancer and colorectal cancer.

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