A water-soluble BODIPY photosensitizer and its preparation method and application

Abstract

The present invention belongs to the technical field of anti-tumor drug preparation, specifically relating to a water-soluble BODIPY photosensitizer, its preparation method, and applications. By modifying the BODIPY structure with a COX-2 targeting unit and a PEG chain, a nanoprobe, I-M-BDP, capable of self-assembly into an amphiphilic nanoprobe, is obtained. I-M-BDP exhibits specific affinity for tumor cells overexpressing COX-2 and good biocompatibility. Compared with the control compound M-BDP, it has better imaging and phototoxicity, and also demonstrates superior PDT in a tumor-bearing Balb / c mouse model. This is attributed to the specific enrichment of I-M-BDP in tumors, which increases the concentration of the photosensitizer in tumor tissue.

Description

Technical Field

[0001] The present invention belongs to the technical field of anti-tumor drug preparation, and particularly relates to a water-soluble BODIPY photosensitizer, a preparation method thereof, and application thereof in the preparation of anti-tumor targeted drugs. Background Art

[0002] Cancer remains the leading cause of death worldwide. Cancer treatment has always faced huge challenges. Traditional treatments have certain side effects. Therefore, it is urgent to study safe and effective cancer treatment strategies. Photodynamic therapy (PDT) is a very promising minimally invasive light therapy that has been used to treat various cancers. PDT has the advantages of tumor selectivity, repeated treatment and low drug resistance, and has attracted widespread attention. PDT is based on the production of cytotoxic reactive oxygen species (ROS) by photosensitizers (PS) after being excited by light of a specific wavelength, especially singlet oxygen ( 1 O2), thereby inducing tumor cell death. In recent years, organic molecules have been widely used in the field of photodynamic therapy due to their safety and easy modification. In addition, their photophysical and therapeutic properties can be precisely controlled by molecular structure. However, there are still many key issues to be solved in organic photosensitizers: (1) Lack of specificity. Due to the non-specific distribution of organic photosensitizers in the body, it is difficult to distinguish between tumor cells and normal cells, and tumor-specific treatment cannot be achieved; (2) Organic molecules themselves have poor water solubility and are prone to aggregation in aqueous solution, resulting in the inability to be transported to tumor tissue through the blood, and aggregation-induced fluorescence quenching (ACQ) will occur; (3) The excitation wavelength of traditional photosensitizers is short. Therefore, solving these problems is currently the key to improving the therapeutic effect of organic photosensitizers.

[0003] Studies have shown that the levels of certain enzymes are significantly increased in tumor cells. Capitalizing on this property, researchers have designed photosensitizers (PS) targeting these enzymes to improve the specificity of PS in cancer tissues. Cyclooxygenase-2 (COX-2) is remarkably overexpressed in various cancer types, such as gastric, colorectal, and pancreatic cancers. In contrast, COX-2 expression levels are relatively low in normal cells. As a prostaglandin-peroxisomal synthase, COX-2's high expression in tumor tissues and cells suggests a potential role in cancer progression. Its overexpression is associated with all stages of cancer and increases with cancer progression. Therefore, COX-2 has been developed as a fluorescent probe for distinguishing cancer cells from normal cells. However, there are few reports on improving the selectivity of photosensitizers by targeting COX-2. Indomethacin (IMC) is a commercially available nonsteroidal anti-inflammatory drug. IMC has been shown to bind to the large hydrophobic side pocket of the COX-2 homodimer. Therefore, IMC was selected as the specific recognition part of COX-2 imaging probe, and its dual targeting of tumors and subcellular targets has been verified. However, only a few photosensitizers have been developed and combined with IMC, mainly due to their weak absorbance in the long wavelength (near-infrared) region, resulting in low photodynamic therapy efficiency and insufficient affinity for tumor tissue.

[0004] Designing and synthesizing highly effective bio-based photosensitizers remains a challenging task due to the significant limitations of general photosensitizers in terms of light penetration, water solubility, and selectivity, and their performance is significantly affected in hypoxic environments. Typically, bio-based photosensitizers have poor hydrophilicity and are prone to aggregation, which results in the formation of large photosensitizer particles that are unable to effectively penetrate cell membranes, thereby affecting cellular uptake efficiency. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention uses indomethacin, N-(6-aminohexyl) tert-butyl carbamate, triethylene glycol monomethyl ether, 3,4,5-trihydroxybenzaldehyde, 2,4-dimethylpyrrole, methyl p-formylbenzoate and benzenesulfonyl chloride as main raw materials, and adopts a step-by-step synthesis method to synthesize N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide, 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde and 4-(5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4A water-soluble BODIPY photosensitizer (IM-BDP) is constructed by reacting PEG (1,2-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolan-10-yl) benzoic acid with a photosensitizer through Knoevenagel condensation and amidation. The water-soluble BODIPY photosensitizer utilizes the hydrophilicity of PEG and the tumor-specific targeting properties of indomethacin to achieve specific enrichment of the IM-BDP photosensitizer in tumor cells, thereby achieving specific tumor targeting.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A water-soluble BODIPY photosensitizer IM-BDP targeting cyclooxygenase-2. The photosensitizer IM-BDP is a spherical nanoparticle. Due to the introduction of a hydrophilic PEG chain into the BODIPY matrix and the coupling with the hydrophobic indomethacin, the IM-BDP self-assembles to form nanoparticles with good dispersion effect in water through hydrophilic and hydrophobic interactions. The molecular formula of the IM-BDP is: C 101 H 137 BClF2I2N5O 28 , the structural formula is as follows:

[0008]

[0009] The present invention also provides a method for synthesizing the IM-BDP, the specific steps of which are as follows:

[0010] Under the conditions of acetic acid and piperidine, 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 Knoevenagel condensation of 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ was performed with dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid and 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde to give 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid; 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid then reacts with N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide under HATU conditions to undergo amidation reaction to finally obtain IM-BDP;

[0011]

[0012] The 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 The structural formula of 1-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid is:

[0013] The structural formula of the 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde is:

[0014]

[0015] The structural formula of the N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide is:

[0016]

[0017] Preferably, the 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid and 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde in a molar ratio of 1:2.5;

[0018] Preferably, the 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4 The molar ratio of 1-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid, N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide and HATU was 1:1.5:1.

[0019] Preferably, the synthesis method of the N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide is as follows:

[0020]

[0021] Under HATU catalysis and DIPEA conditions, tert-butyl N-(6-aminohexyl)carbamate and indomethacin are subjected to an amidation reaction (preferably, the molar ratio of indomethacin to tert-butyl N-(6-aminohexyl)carbamate is 5:7.5); then, under trifluoroacetic acid conditions, BOC removal is carried out to finally obtain N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide;

[0022] The N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide has a strong effect on COX-2 because COX-2 contains a hydrophobic cavity that interacts with indomethacin, allowing it to be firmly embedded in COX-2.

[0023] Preferably, the synthesis method of the 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde is as follows:

[0024] Triethylene glycol monomethyl ether and benzenesulfonyl chloride undergo a substitution reaction to obtain a sulfonylated product, and the sulfonylated product reacts with 3,4,5-trihydroxybenzaldehyde under a nitrogen atmosphere and weak base conditions (preferably, the molar ratio of the sulfonylated product to 3,4,5-trihydroxybenzaldehyde is 1:4) to ultimately obtain 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde;

[0025] The 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde molecule has three long ether chains and can form multiple hydrogen bonds with water molecules, so it has good water solubility.

[0026] Preferably, the 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 The synthesis method of 1-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid is as follows:

[0027] (1) In the presence of trifluoroacetic acid in a protective gas atmosphere, 2,4-dimethylpyrrole reacts with methyl paraformylbenzoate, DDQ is added and stirred to complete the reaction, and then triethylamine and boron trifluoride-ether complex are added to react to obtain methyl 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolin-10-yl)benzoate;

[0028] (2) In a protective gas atmosphere, under alkaline conditions, methyl 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrole [1,2-c: 2',1'-f][1,3,2]diazaborolidine indol-10-yl) benzoate was dissolved and refluxed to completely obtain 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolin-10-yl)benzoic acid; under iodic acid conditions, 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolidine indol-10-yl)benzoic acid reacts with iodine to give 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid;

[0029] Preferably, the molar ratio of the 2,4-dimethylpyrrole to methyl paraformylbenzoate and DDQ is 2:1:1; the 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolin-10-yl)benzoic acid to iodine and iodic acid in a molar ratio of 1:2.5:2;

[0030] The IM-BDP molecule contains indomethacin and multiple ether chains, which enable it to have good water solubility in aqueous solution and the ability to target COX-2 overexpressing cancer cells. It can also generate a large amount of ROS under light conditions and has a good PDT therapeutic effect.

[0031] Therefore, the present invention also provides the use of the above IM-BDP or the IM-BDP obtained by the above synthesis method in the preparation of COX-2 fluorescent probes or anti-tumor targeted drugs.

[0032] Compared with the prior art, the technical solution of the present invention has the following advantages and beneficial effects:

[0033] 1. The novel BODIPY photosensitizer designed and synthesized in the present invention is synthesized by convergent reaction. This method has the advantages of high yield, NIR (mainly in the first near-infrared NIR-I window, 650-900nm) fluorescence emission and excellent ROS generation performance, which is conducive to its application in the biomedical field.

[0034] 2. The novel amphiphilic small molecule (IM-BDP) designed and synthesized in the present invention has tumor cell targeting and self-assembly properties, and can self-assemble to form core-shell nanomicelles in aqueous solution.

[0035] 3. The average particle size of the IM-BDP photosensitizer micelles is 134 nm, and it has an EPR (high permeability and long retention) effect, which has great application potential in biological fields such as the preparation of drug carriers and controlled drug release.

[0036] 4. The present invention uses BODIPY as a photosensitizer matrix and modifies functional groups to synthesize a near-infrared, water-soluble BODIPY photosensitizer with tumor targeting capabilities. By coupling BODIPY with indomethacin to enhance the photosensitizer's targeting ability and introducing PEG chains to enhance its water solubility, a photosensitizer, IM-BDP, was obtained that has the ability to target tumor cells overexpressing cyclooxygenase (COX-2). Results showed that IM-BDP has good targeting ability and low cytotoxicity for tumor cells. The practical application of the IM-BDP-based PDT treatment platform was demonstrated using a breast cancer mouse model, with good results. Commonly used BODIPY photosensitizers are insoluble in water, while the photosensitizer containing PEG chains has good water solubility. Compared to commonly used polymer micelles, the molecules themselves can self-assemble into micelles, offering advantages such as non-toxicity, good biocompatibility, and diverse functionality. Furthermore, when encapsulating photosensitizers with amphiphilic polymers, the encapsulation content must be considered. By coupling indomethacin to the molecule, the molecule can be more targeted and retained in tumors, providing new research ideas for accurate visual tumor diagnosis and treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The IM-BDP synthesized in Example 1 1 H NMR spectrum;

[0038] Figure 2 This is the MALDI-TOF MS spectrum of IM-BDP synthesized in Example 1;

[0039] Figure 3 The absorption and emission spectra of IM-BDP synthesized in Example 2 are shown;

[0040] Figure 4 TEM and DLS spectra of IM-BDP synthesized in Example 3;

[0041] Figure 5 This is a graph showing the ROS generation performance test results of IM-BDP in Example 4;

[0042] Figure 6 This is a graph showing the experimental results of cellular uptake of IM-BDP in Example 5;

[0043] Figure 7 The figure shows the results of the dark cytotoxicity and phototoxicity experiments of IM-BDP in Example 5; Figure 8 This is a graph showing the results of the tumor cell targeting inhibition experiment of IM-BDP in Example 5;

[0044] Figure 9 This is a diagram showing the results of the cell co-localization experiment of IM-BDP in Example 5;

[0045] Figure 10 This is a graph showing the results of the IM-BDP live-dead staining experiment in Example 5;

[0046] Figure 11 This is a graph showing the experimental results of the ROS production performance of IM-BDP in tumor cells in Example 5;

[0047] Figure 12 This is the result of the IM-BDP tumor-bearing mouse imaging experiment in Example 6;

[0048] Figure 13 This is a diagram showing the experimental results of IM-BDP treatment of tumor-bearing mice in Example 6. DETAILED DESCRIPTION

[0049] The applicant will now describe the technical solution of the present invention in detail with reference to specific embodiments and accompanying drawings, so that those skilled in the art can clearly understand the present invention. However, the following embodiments should not be interpreted in any way as limiting the scope of protection claimed in the claims of the present invention.

[0050] The reagents used in the following examples are all common commercially available products, and the purity level is all analytical grade.

[0051] In the following examples, the ratios between the liquids during extraction and elution refer to volume ratios.

[0052] Example 1: Synthesis of IM-BDP

[0053]

[0054] (1) Synthesis of Compound 1

[0055] Indomethacin (5 mmol), tert-butyl N-(6-aminohexyl)carbamate (7.5 mmol), and HATU (5 mmol) were added to a round-bottom flask, and DMF (20 mL) was added. N,N-diisopropylethylamine (DIPEA) (5 mmol) was added dropwise. The mixture was stirred at room temperature (25°C, the same below) overnight (overnight in the present invention specifically refers to 12 hours). The reaction was monitored by thin-layer chromatography (developing solvent: ethyl acetate / petroleum ether = 4:1, v / v). After the raw materials reacted completely, the reaction was stopped and extracted with a mixture of dichloromethane (50 mL) and water (dichloromethane / water = 1:10). The organic layer was collected and dried over anhydrous sodium sulfate. The solvent was removed by distillation under reduced pressure. The crude product was purified by silica gel column chromatography using dichloromethane as the eluent to obtain a light yellow solid, namely compound 1, with a yield of 55% in this step.

[0056] 1 H NMR(400MHz,Chloroform-d)δ7.71–7.63(m,2H),7.54–7.45(m,2H),6.93–6.83(m,2H),6.71(dd,J=9.0,2.5Hz,1H),5.77(s,1H),4.55(d ,J=6.9Hz,1H),3.83(s,3H),3.65(s,2H),3.20(q,J=6.7Hz,2H),3.10–2.95(m,2H),2.40(s,3H),1.31-1.42(m,13H),1.15-1.26(m,4H).

[0057] (2) Synthesis of compound 2-(N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide)

[0058] Compound 1 (1.77 mmol) and DMF (10 mL) were added to a round-bottom flask, and trifluoroacetic acid (18 mmol) was added dropwise. The mixture was reacted at room temperature for 30 min. The solvent was removed by distillation under reduced pressure from the reaction mixture. The crude product was purified by silica gel column chromatography using (dichloromethane / methanol = 1:50) as the eluent to obtain (N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide) as a white solid. The yield of this step was 85%. 1H NMR (600MHz, DMSO-d6) δ7.71–7.63(m,4H),7.12(d,J=2.6Hz,1H),6.93(d,J=9.0Hz,1H),6.71(dd,J=9.0,2.6Hz,1H),3.76(s,3H),3 .49(s,2H),3.05(q,J=6.6Hz,2H),2.78–2.72(m,2H),2.23(s,3H),1.48(q,J=7.5Hz,2H),1.39(q,J=7.1Hz,2H),1.26–1.24(m,4H).

[0059] (3) Synthesis of Compound 3

[0060] In a round-bottom flask, triethylene glycol monomethyl ether (60.9 mmol) was dissolved in 50 mL of tetrahydrofuran and stirred at 0°C in a cold trap. 30 mL of a 20% sodium hydroxide solution was added, and then a benzenesulfonyl chloride solution (12 g of benzenesulfonyl chloride dissolved in 50 mL of THF) was added dropwise under constant pressure. After 30 min of complete addition, the mixture was stirred at room temperature for 12 h, and the pH was adjusted to 7.0 with 3 mol / L hydrochloric acid. The mixture was extracted with 50 mL of dichloromethane. The organic layer was washed three times with deionized water (300 mL each time), dried over anhydrous sodium sulfate, filtered, and the filtrate was distilled under reduced pressure to give a pale yellow oily crude product. The product was purified by silica gel column chromatography using (petroleum ether / dichloromethane = 10 / 1) as eluent to give the sulfonylated product, i.e., compound 3, as a colorless oily liquid for standby use. The yield of this step was 54%. 1 H NMR(600MHz,Chloroform-d)δ7.85–7.80(m,2H),δ7.20–7.32(m,1H)7.05–6.99(m,2H),4.24–4.20(m,2H),3 .91–3.88(m,2H),3.77–3.74(m,2H),3.71–3.68(m,2H),3.67–3.64(m,2H),3.57–3.53(m,2H),3.38(s,3H).

[0061] (4) Synthesis of compound 4-(3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde)

[0062] 150 mL of N,N-dimethylformamide was added to a three-necked flask and nitrogen was passed through for 30 min. 3,4,5-trihydroxybenzaldehyde (7.85 mmol) was added thereto. Under nitrogen conditions, the sulfonylated product (31.41 mmol) obtained in step (3) and potassium carbonate (47.11 mmol) were added thereto, stirred evenly, heated to 90° C. for reaction for 24 h, cooled to room temperature, and extracted with 100 mL of dichloromethane. The organic layer was taken and washed three times with saturated sodium chloride aqueous solution (200 mL each time), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated by distillation under reduced pressure. The filtrate was purified by silica gel column chromatography using (petroleum ether / dichloromethane = 2 / 1) as eluent to obtain a light brown oily liquid - compound 4, which was set aside. 1 H NMR(600MHz,Chloroform-d)δ9.75(s,1H),7.07(s,2H),4.20(t,J=4.6Hz,2H),4.16(t,J=4.5Hz,4H),3.81(t,J=4.5Hz, 4H), 3.74 (d, J=4.7Hz, 3H), 3.69–3.63 (m, 6H), 3.58 (ddt, J=15.5, 10.7, 4.5Hz, 12H), 3.47 (q, J=4.4Hz, 6H), 3.31 (s, 9H).

[0063] (5) Synthesis of Compound 5

[0064] Under nitrogen, 2,4-dimethylpyrrole (6.25 mL, 60.96 mmol) and methyl p-formylbenzoate (5 g, 30.48 mmol) were added to a 1L three-necked flask. An appropriate amount of dichloromethane was added to dissolve the mixture. After stirring for 15 minutes, 0.4 mL of trifluoroacetic acid was added and the mixture was stirred thoroughly overnight at room temperature to obtain a mixed solution. Dichlorodicyanobenzoquinone DDQ (7 g, 30.48 mmol) was added to the mixture and stirred at room temperature for 4 hours. Triethylamine (76.2 mL, 60.96 mmol) was added and stirred for 20 minutes. Boron trifluoride-diethyl ether complex (76.2 mL, 60.96 mmol) was then added and the reaction was continued for 12 hours before stopping the reaction. The reaction solution obtained above was washed with saturated brine, and the organic phase was collected and concentrated by evaporation. The mixture was separated and purified by silica gel column chromatography using dichloromethane as eluent. The bright green fluorescent solution was collected and concentrated by evaporation to obtain a bright green solid, namely compound 5. The yield of this step was 17.17%. 1 H NMR (600MHz, Chloroform-d) δ8.18(d,J=7.8Hz,2H),7.41(d,J=7.8Hz,2H),5.99(s,2H),3.97(s,3H),2.56(s,6H),1.36(s,6H).

[0065] (6) Synthesis of Compound 6

[0066] Compound 5 (1 g, 2.6 mmol) was added to a three-necked flask containing methanol (150 mL) under nitrogen, and 15 mL of a 15% NaOH solution was added dropwise. The mixture was refluxed at 80°C for 4 hours. TLC (developing solvent: ethyl acetate / petroleum ether = 4:1, v / v) was used to monitor the reaction. The reaction was stopped after the starting materials had reacted completely. After cooling to room temperature, the solution was acidified by adding a 15% HCl solution and the pH was adjusted to 3-4, resulting in the precipitation of a solid. The mixture was filtered, and the filter cake was repeatedly washed with distilled water until the filtrate had a pH of 7. The product was dried to obtain a red crude product. The crude product was purified by silica gel column chromatography using chloroform / methanol = 95:5, v / v as the eluent to obtain a red solid, compound 6, with a yield of 93%. 1 H NMR (600MHz, DMSO-d6) δ8.14–8.06(m,2H),7.57–7.47(m,2H),6.20(s,2H),2.46(s,6H),1.33(s,6H).

[0067] (7) Compound 7 (4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid)

[0068] Under nitrogen, compound 6 (1 g, 3.08 mmol), iodine (1.95 g, 7.69 mmol), and ethanol (50 mL) were added to a round-bottom flask. Iodic acid (2.5 g, 6.11 mmol) was dissolved in water (5 mL) and added dropwise to the round-bottom flask with stirring at room temperature. The mixture was heated to 60°C and stirred for 1 h. The reaction was monitored by TLC (developing solvent: ethyl acetate / petroleum ether = 4:1, v / v). The reaction was stopped after the complete disappearance of the starting material spot. The mixture was extracted with a mixture of 100 mL of dichloromethane and 300 mL of water. The organic layer was collected, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using dichloromethane as the eluent to obtain a red solid, compound 7, with a yield of 60% in this step. 1 H NMR (600MHz, DMSO-d6) δ8.11(d,J=7.7Hz,2H),7.52(d,J=7.7Hz,2H),2.55(s,6H),1.33(s,6H).

[0069] (8) M-BDP (4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4 Synthesis of 1,2-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid

[0070] 50 mL of anhydrous toluene was added to a three-necked flask and nitrogen was passed through for 30 minutes. Compound 7 (1 g, 1.6 mmol) was then added, followed by compound 4 (2.4 g, 4.03 mmol), followed by 1 mL of acetic acid, and finally 1 mL of piperidine. Under nitrogen protection, the mixture was heated to 120° C. and stirred overnight. The mixture was cooled to room temperature and extracted with a mixture of 100 mL of dichloromethane and 300 mL of water. The organic layer was dried over anhydrous sodium sulfate and the solvent was removed by distillation under reduced pressure. The crude product was purified by silica gel column chromatography using (dichloromethane / methanol = 20 / 1) as eluent to obtain 200 mg of a gray-green oily liquid, namely M-BDP, with a yield of 37% in this step. 1 H NMR(600MHz,Chloroform-d)δ7.91(d,J=16.5Hz,2H),7.41(d,J=16.5Hz,2H),7.32(s,3H),6.84(d,5H),4.23(t,J=5.5Hz,12 H),3.87(t,J=4.7Hz,8H),3.81(m,6H),3.78–3.70(m,12H),3.68–3.61(m,24H),3.54(dd,J=5.9,3.5Hz,12H),3.37(s,18H).

[0071] (9)IM-BDP synthesis

[0072] Compound M-BDP (1 mmol), compound 2 (1.5 mmol), and HATU (1 mmol) were placed in a round-bottom flask. 7 mL of DMF was added, and DIPEA (5 mmol) was added dropwise, followed by stirring at room temperature overnight. The reaction was monitored by thin-layer chromatography (developing solvent: ethyl acetate / petroleum ether = 4:1, v / v). After the starting materials had reacted completely, the reaction was stopped and extracted with a mixture of 100 mL of dichloromethane and 300 mL of water. The organic layer was dried over anhydrous sodium sulfate, and the solvent was removed by distillation under reduced pressure. The crude product was purified by silica gel column chromatography using dichloromethane as the eluent to obtain the compound, IM-BDP, as a green colloid. The yield for this step was 35%.

[0073] 1H NMR(600MHz,Chloroform-d)δ8.02(d,J=8.1Hz,2H),7.95(d,J=16.5Hz,2H),7.69–7.66(m,4H),7.49(dd,J= 9.2,2.0Hz,6H),6.85(s,5H),4.21(t,J=13.1,5.2Hz,12H),3.86(t,J=5.0Hz,11H),3.82–3.78(m,8H),3.72 (m,J=11.5,2.9Hz,12H),3.64(m,J=14.0Hz,24H),3.54(dd,J=15.0Hz,12H),3.39–3.33(s,18H),3.25(m,2H ),3.11(t,2H),2.40(s,3H),1.44(s,2H).CalcdforC101H137BClF2I2N5O28[M]+,2206.732; found,2206.32.

[0074] The molecular weight was determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and the actual molecular weight was 2206.327. Figure 2 , which is consistent with the theoretical value (theoretical molecular weight is 2206.732). 1 H NMR data ( Figure 1 ), proving that the IM-BDP photosensitizer was successfully synthesized.

[0075] Example 2: UV absorption and fluorescence spectroscopy characterization

[0076] The concentration of photosensitizer IM-BDP was prepared with deionized water to 1.0×10 -2 The photophysical properties of the photosensitizer were measured in 10 mM pH 7.4 PBS buffer. The photosensitizer was diluted to 10 μM before each spectral measurement. The photophysical properties of IM-BDP were characterized by UV-visible absorption spectroscopy and fluorescence spectroscopy. Figure 3 As shown in the figure, IM-BDP has a clear absorption peak at 665nm and the maximum emission wavelength of IM-BDP is around 720nm, which indicates that the photosensitizer has good absorption and emission in the near-infrared region.

[0077] Example 3: Material Characterization Experiment

[0078] The photosensitizer IM-BDP was prepared with deionized water to a concentration of 100 mM, and the sample morphology was characterized by transmission electron microscopy (TEM) and the sample particle size was measured by dynamic light scattering (DLS). Figure 4As shown in Figure 4A, the hydrodynamic mean particle size of IM-BDP determined by DLS is 134 nm. Similarly, the TEM image (4B) shows IM-BDP as uniformly spherical particles with a particle size of approximately 80-120 nm. The discrepancy between the TEM and DLS sizes may be due to shrinkage of the water layer during the drying process of the TEM sample.

[0079] Example 4: Photodynamic performance test

[0080] In vitro IM-BDP 1 The O2 production rate was tested using 1,3-diphenylisobenzofuran (DPBF) as a scavenger. The photodynamic properties of the compound were evaluated by UV-visible absorption spectroscopy. The photodynamic properties of the compound were evaluated by 660 nm laser (40 mW / cm 2 ) as the excitation source. The mixed aqueous solution containing IM-BDP (10 μM) and DPBF (50 μM) was transferred to a quartz cuvette and excited with a 660 nm (40 mW / cm 2 ) for a certain period of time, and the absorbance of DPBF at 418 nm was monitored, with a DPBF (50 μM) aqueous solution as a control. Figure 5 (A) and (C) Figure 5 (C), A0 is the original absorbance value of each group before laser irradiation). As the laser irradiation time increases, the absorption peak intensity of the DPBF solution with the addition of IM-BDP at 418 nm continues to decrease, while the absorption peak intensity of the DPBF solution without the addition of IM-BDP at 418 nm remains basically unchanged ( Figure 5 (B) and (C)), indicating that IM-BDP has singlet oxygen ( 1 O2) production capacity.

[0081] Select TEMP as 1 The O2 spin trap was further verified by electron paramagnetic resonance (EPR) spectroscopy. 1 O2 is produced. Figure 5 (D) shows the electron paramagnetic resonance signal (red line) and EPR signal (black line) of a mixed aqueous solution containing IM-BDP (1 mM) and TEMP (100 μM) after 660 nm laser irradiation. 1 O2 matches the characteristic paramagnetic adduct, indicating that the ROS generated is 1 O2.

[0082] Example 5: Evaluation of the therapeutic efficacy of IM-BDP at the cellular level

[0083] 4T1 cells (Pnosai, Wuhan; all other cells were purchased from the same company) were cultured in DMEM (1% penicillin / streptomycin and 10% fetal bovine serum) and incubated in a 37°C cell culture incubator with 5% CO2. Prior to fluorescence imaging, cells were seeded at an appropriate density into confocal microplates and incubated for 24 hours in a 37°C cell culture incubator with 5% CO2 to obtain a 4T1 cell suspension for the following assays.

[0084] Unless otherwise specified, the following cell cultures were all cultured at 37° C. in a cell culture incubator containing 5% CO 2 ; all culture media used were DMEM (1% penicillin / streptomycin and 10% fetal bovine serum).

[0085] IM-BDP cell uptake experiment: 4T1 cells were seeded into confocal microplates and incubated in a 37°C, 5% CO2 incubator for 24 hours. After the cells adhered, the microplates were washed with PBS (10mM pH=7.4 PBS buffer, the same below), and 1mL of culture medium containing 10μM IM-BDP was added for further incubation. Confocal imaging results of 4T1 cells were collected at different incubation times. Figure 6 As shown in the figure, as the incubation time increases, IM-BDP can be taken up by tumor cells, and the fluorescence intensity reaches the maximum value at 120min to 150min, which provides a reference for the incubation time of cells with materials during subsequent treatment.

[0086] IM-BDP cytotoxicity test: The phototoxicity and dark toxicity of IM-BDP were detected by CCK8 assay.

[0087] 4T1 cell suspension was cultured at 5×10 3 Cells were seeded into 96-well plates at a density of 100 μM / well and cultured in a cell culture incubator for 24 h. After the cells adhered, the culture medium was removed and IM-BDP solutions with concentrations of 0, 0.5, 1, 2.5, 5, and 10 μM were prepared with DMEM medium and 100 μL was added to each well. After incubation for 2 h, the cells were illuminated with a 660 nm laser (40 mW / cm 2 Each well was irradiated for 10 minutes and incubated for an additional 12 hours. The culture medium was aspirated, and 100 μL of fresh culture medium and 10 μL of CCK8 solution were added to each well. The cells were incubated in a 5% CO2 incubator for 1 hour, and the absorbance at 450 nm was recorded using a microplate reader. Cell viability was calculated according to the following equation:

[0088] Cell Viability (%) =

[0089] ((ODsample-ODbackground) / (ODcontrol-ODbackground))*100%;

[0090] ODsample: experimental group (culture medium containing cells, CCK8, IM-BDP);

[0091] ODcontrol: control group (culture medium containing cells, CCK8, and no IM-BDP);

[0092] ODbackground: blank group (culture medium without cells and IM-BDP, CCK8);

[0093] A control group was set up in the dark (-light, without laser irradiation).

[0094] The cell viability of 4T1 cells after incubation with different concentrations of IM-BDP (0-10 μM) for 2 h was determined using the CCK8 kit. Figure 7 As shown in Figure 2, under dark conditions (-light), as the concentration of the photosensitizer increases, when the concentration of IM-BDP reaches 10 μM, the cell survival rate is still above 90%, indicating good biocompatibility. 2 ) laser irradiation for 10 minutes. As the concentration of IM-BDP increased, the cell survival rate decreased. At a concentration of 10 μM, the survival rate of 4T1 cells dropped below 20%. This result demonstrates that IM-BDP can effectively kill tumor cells under laser irradiation. IM-BDP exhibits high phototoxicity and exhibits a significant inhibitory effect on tumor cell growth.

[0095] Cell-targeted inhibition experiment: cells were seeded in a small dish and placed in an incubator (37°C, 5% CO2) for 24 hours. After the cells attached, the dish was washed with PBS and then incubated with a medium containing 15 μM Aceclofenac for 2 hours. After that, the medium was aspirated and 1 mL of a medium containing 10 μM IM-BDP was added. The dish was placed in an incubator (37°C, 5% CO2) for 2 hours. After washing with PBS three times, confocal imaging was performed. Figure 8 As shown in the figure, the IM-BDP group, a control group that did not contain 15 μM aceclofenac and then incubated for 2 hours, showed a distinct fluorescence signal in various tumor cell types, while the fluorescence signal in normal cells was very weak and negligible. After treatment with the COX-2 inhibitor aceclofenac, the fluorescence signal in various cell types was also very weak. These results demonstrate that IM-BDP stains tumor cells well, is insensitive to normal cells, and that the fluorescence signal is generated only when it interacts with intracellular COX-2.

[0096] Organelle colocalization experiment:

[0097] 4T1 cells were seeded in a small dish and placed in a (37°C, 5% CO2) incubator for 24 hours. After the cells attached, the dish was washed with PBS, 1 mL of culture medium containing 10 μM IM-BDP (or 10 μM M-BDP) was added, and the dish was placed in a (37°C, 5% CO2) incubator for 1 hour. The 4T1 cells were then treated with Golgi-Tracker Green for 30 minutes, washed three times with PBS, and imaged. Figure 9 As shown in the figure, the photosensitizer IM-BDP and Golgi-Tracker Green have good overlap, with the Pearson coefficient reaching 0.685, while the Pearson coefficient of M-BDP and Golgi-Tracker Green is only 0.210, which indicates that the Pearson coefficient of the photosensitizer IM-BDP is much larger than that of M-BDP, and IM-BDP can be preferentially distributed in the Golgi apparatus, laying the foundation for subsequent treatment.

[0098] Live and dead cell staining:

[0099] 4T1 cells treated with different conditions were stained for live and dead cells using the AM-PI Live / Dead Cell Staining Kit. Calcein-AM (green) and propidium iodide (PI) were used to detect live and dead cells, respectively.

[0100] 4T1 cells were seeded in a confocal microplate and cultured for 24 h. The culture medium was aspirated and 1 mL of 10 μM IM-BDP DMEM solution was added and incubated for 2 h. The cells were then illuminated with a 660 nm (40 mW / cm 2 Cells were irradiated with a laser for 10 minutes and cultured for an additional 12 hours. PBS (1 mL) containing AM (4 μM) and PI (6 μM) was added and the cells were stained for 20 minutes before confocal imaging. The following control groups were also established: IM-BDP (not irradiated with laser), light (irradiated with laser but without IM-BDP), and PBS (not irradiated with laser but without IM-BDP).

[0101] like Figure 10 As shown, the IM-BDP, light, and PBS control groups showed green fluorescence in the green channel and no significant red fluorescence in the red channel, indicating that cells remained viable after all three treatment conditions. However, after treatment with IM-BDP + light (laser irradiation), there was no significant green fluorescence in the green channel, but significant red fluorescence in the red channel. This indicates that IM-BDP can almost completely kill 4T1 cells under 660nm laser irradiation. These results demonstrate that cytotoxicity is maximized and therapeutic efficacy is optimal when IM-BDP is co-incubated with light and then treated.

[0102] Intracellular 1 O2 detection: DCFH-DA probe is used to detect intracellular 1 O2 was detected. 4T1 cells were treated with IM-BDP in DMEM (10 μM) for 2 h at 37°C and then illuminated with a 660 nm laser (40 mW / cm 2 ) irradiate the cells for 10 minutes and continue to culture for 12 hours. Aspirate the original culture medium, incubate with culture medium containing 20μM DCFH-DA for 30 minutes, wash three times with PBS and perform confocal imaging. Set up the following control groups: Control control group (no laser irradiation, no IM-BDP); IM-BDP+Aceclofenac+light treatment group (refer to the cell targeted inhibition experiment for Aceclofenac incubation for 2 hours, then add IM-BDP DMEM solution and incubate for 2 hours, then irradiate with 660nm 40mW / cm 2 Laser irradiation of cells for 10 min), light (laser irradiation, without IM-BDP), Aceclofenac (refer to the cell-targeted inhibition experiment for Aceclofenac incubation for 2 hours), and IM-BDP (without laser irradiation).

[0103] like Figure 11 As shown, in the control group, IM-BDP, Aceclofenac, light and IM-BDP+

[0104] The aceclofenac + light treatment group showed a very low green fluorescence signal, indicating that the amount of ROS generated during this process was negligible. However, when IM-BDP + light treatment was applied and irradiated with a 660nm laser, the 4T1 cells displayed bright green fluorescence, indicating that a large amount of ROS was generated during this process. These results indicate that IM-BDP can generate cell-damaging ROS under 660nm laser irradiation, further demonstrating that IM-BDP can kill tumor cells by generating ROS under light conditions.

[0105] Example 6: In vivo fluorescence imaging and photodynamic therapy

[0106] 4T1 cells (1×10 6 4T1 tumor-bearing mouse models were established by subcutaneously injecting 4T1 cells into the back of each mouse. When the tumor volume grew to about 100 mm 3 In vivo imaging was performed by injecting IM-BDP solution prepared with PBS into Balb / c mice bearing 4T1 tumors via tail vein injection. Figure 12As shown, 10 minutes after injection, fluorescence was observed in the tumor using an in vivo imaging device, indicating that the photosensitizer accumulated near the tumor. As injection time increased, fluorescence gradually increased, reaching a peak in the tumor, followed by a slow decline. The peak fluorescence intensity of IM-BDP was reached at 4 hours, indicating that 4 hours after injection is the optimal illumination time.

[0107] Balb / c mice bearing 4T1 tumors were randomly divided into 6 groups: a) PBS group (100 μL); b) PBS (100 μL) + light group; c) M-BDP (5×10 -3 μM, 100 μL) group; d) IM-BDP (5×10 -3 μM, 100 μL); e) M-BDP (5×10 -3 μM, 100 μL)+light group; f) IM-BDP (5×10 -3 μM, 100 μL) + light group, the above “+ light” refers to 660 nm 200 mW / cm 2 Irradiate with laser for 15 minutes. Figure 13 As shown, in groups e) and f), 4 h after the tail vein injection of the material, the mice were continuously irradiated with light (660 nm 200 mW / cm 2 ) for 15 minutes. Mice were fed for another 14 days, and their body weight and tumor volume were monitored daily. After 14 days of treatment, the body weight of the mice showed a slow upward trend. Meanwhile, the tumor volume in the PBS, M-BDP, and PBS+light groups increased by approximately 5.5 times compared to the original tumor volume. The tumor volume in the IM-BDP group increased by approximately 4.5 times, the tumor volume in the M-BDP+light group increased by approximately 3.8 times, and the tumor volume in the IM-BDP+light group increased by approximately 0.3 times. This indicates that M-BDP has little inhibitory effect on tumor growth under 660nm laser irradiation, while IM-BDP effectively inhibits tumor growth under 660nm laser irradiation. This is because IM-BDP incorporates indomethacin, which interacts with the hydrophobic pocket of COX-2, allowing IM-BDP to accumulate in tumor tissue and remain intracellular for a long time without being metabolized. These properties of IM-BDP contribute to its significant tumor inhibitory effect. Therefore, IM-BDP has a good photodynamic effect.

[0108] The present invention prepares a photosensitizer, IM-BDP, that can target tumor cells for PDT treatment of tumors. IM-BDP is selective for tumor cells overexpressing COX-2 and produces 1O2 under a 660nm laser. In vitro cell confocal microscopy, cytotoxicity, and live-dead staining experiments demonstrate that IM-BDP can target tumor cells and exhibits excellent phototoxicity. IM-BDP can kill 4T1 cells at a rate of 84%. Furthermore, the therapeutic efficacy of IM-BDP in vivo was evaluated using tumor-bearing mice, demonstrating excellent tumor inhibition in these experiments. These experiments demonstrate that the IM-BDP photosensitizer, coupled with indomethacin, possesses tumor cell targeting and near-infrared light-induced PDT therapeutic properties.

Claims

1. A water-soluble BODIPY photosensitizer IM-BDP targeting cyclooxygenase-2, wherein the photosensitizer IM-BDP is a spherical nanoparticle, and the molecular formula of the IM-BDP is: C 101 H 137 BClF2I2N5O 28 , whose structural formula is shown in the following formula (1):

2. A method for synthesizing the IM-BDP according to claim 1, comprising the following steps: Under the conditions of acetic acid and piperidine, 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 Knoevenagel condensation of 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ was performed with dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid and 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde to give 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid; 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid then reacts with N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide under HATU conditions to undergo amidation reaction to finally obtain IM-BDP; The 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 The structural formula of 1,2-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid is formula (2): The structural formula of the 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde is formula (3): The structural formula of the N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide is formula (4):

3. The synthesis method according to claim 2, characterized in that The 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid and 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde in a molar ratio of 1:2.5; and / or The 4-[5,5-difluoro-2,8-diiodo-1,9-dimethyl-3,7-bis[(E)-3,4,5-tris[2-(2-(2-methoxyethoxy)ethoxy)ethoxy]phenyl]-5H-4λ 4 ,5λ 4 The molar ratio of 1-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolyl]benzoic acid, N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide and HATU was 1:1.5:

1.

4. The synthesis method according to claim 2, characterized in that The synthesis method of the N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide is as follows: Under HATU catalysis and DIPEA conditions, tert-butyl N-(6-aminohexyl)carbamate and indomethacin were subjected to amidation reaction; then, under trifluoroacetic acid conditions, de-BOC was carried out to finally obtain N-(6-aminohexyl)-2-(1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl)acetamide.

5. The synthesis method according to claim 2, characterized in that The synthesis method of the 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde is as follows: Triethylene glycol monomethyl ether and benzenesulfonyl chloride undergo a substitution reaction to obtain a sulfonylated product, which is then reacted with 3,4,5-trihydroxybenzaldehyde under a nitrogen atmosphere and a weak base to ultimately obtain 3,4,5-tris[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzaldehyde.

6. The synthesis method according to claim 2, characterized in that The 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 The synthesis method of 1-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaboryl]benzoic acid is as follows: (1) In the presence of trifluoroacetic acid in a protective gas atmosphere, 2,4-dimethylpyrrole reacts with methyl paraformylbenzoate, DDQ is added and stirred, and then triethylamine and boron trifluoride-ether complex are added to react to obtain methyl 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolin-10-yl)benzoate; (2) In a protective gas atmosphere, under alkaline conditions, methyl 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrole [1,2-c: 2',1'-f][1,3,2]diazaborolidine indol-10-yl) benzoate was dissolved and refluxed to completely obtain 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolin-10-yl)benzoic acid; under iodic acid conditions, 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolidine indol-10-yl)benzoic acid reacts with iodine to give 4-[5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 -dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolanyl]benzoic acid.

7. The synthesis method according to claim 6, characterized in that The molar ratio of the 2,4-dimethylpyrrole to methyl paraformylbenzoate and DDQ is 2:1:1; the 4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4λ 4 ,5λ 4 The molar ratio of 1,2-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborolin-10-yl)benzoic acid to iodine and iodic acid is 1:2.5:

2.

8. Use of the IM-BDP according to claim 1 or the IM-BDP obtained by the synthesis method according to any one of claims 2 to 7 in the preparation of a COX-2 fluorescent probe.

9. Use of the IM-BDP according to claim 1 or the IM-BDP obtained by the synthesis method according to any one of claims 2 to 7 in the preparation of anti-tumor targeted drugs.

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