BODIPY-based near-infrared heavy-atom-free photosensitizer and preparation method and application thereof

Abstract

The present invention discloses a BODIPY-based near-infrared heavy-atom-free photosensitizer, a preparation method and an application. The photosensitizer has a structure as shown in formula (I), which is a series of new structural small molecule compound photosensitizers with BODIPY dimer as the basic skeleton and without heavy atoms, with a maximum absorption wavelength of 700-800nm, low dark toxicity, long triplet lifetime, and high reactive oxygen generation capacity under near-infrared light excitation. It overcomes the defects of similar photosensitizer molecules with short absorption wavelengths, and the introduction of heavy atoms to improve photosensitivity while significantly reducing triplet lifetime and singlet oxygen yield in anoxic environments. Compared with the common photosensitizer molecule indocyanine green, it has lower dark toxicity and higher photostability, can significantly increase the applicability of photodynamic agents, and has a simple preparation method, high reaction efficiency, high yield, and good industrial application prospects;

Description

Technical Field

[0001] The invention belongs to the technical field of functional organic small molecules, and particularly relates to a BODIPY-based near-infrared heavy-atom-free photosensitizer and a preparation method and application thereof. Background Art

[0002] Photodynamic therapy (PDT) has the advantages of low invasiveness, high controllability, low toxicity and high spatiotemporal precision. It is a safe, efficient and low-cost cancer treatment technology and has been widely studied in the treatment of solid tumors, such as melanoma, skin cancer, esophageal cancer and lung cancer. The mechanism of PDT is that photosensitizers (PSs) react with oxygen and other substances under light excitation conditions to produce reactive oxygen species (ROS). Reactive oxygen species are highly reactive and can induce cell apoptosis or necrosis, microvascular closure and immune response, thereby curing diseases such as cancer. Among them, increasing the lifetime of the triplet excited state of photosensitizer molecules is a key factor in enhancing the efficiency of ROS generation.

[0003] BODIPY molecules have excellent photophysical and chemical properties. By introducing cyclization or appropriate substituents, their various properties can be precisely controlled. They are very potential photosensitizer candidates. BODIPY molecules need to be modified to have a strong ability to generate reactive oxygen. The most classic and commonly used strategy is to introduce heavy atoms. Commonly used heavy atoms include transition metal elements such as ruthenium, palladium, iridium, and platinum, as well as non-metallic heavy atom elements such as bromine and iodine. The heavy atom modification effect is stable and the principle is clear, but it also brings high costs, high dark toxicity and greatly shortened triplet lifetime. The ability to generate reactive oxygen is low, which seriously affects its application in the biomedical field. There is an urgent need to develop near-infrared heavy atom-free photosensitizers. Summary of the invention

[0004] In order to overcome the problems of cost, dark toxicity and low reactive oxygen generation capacity caused by the introduction of heavy atoms in BODIPY-based photosensitizer molecules in the prior art, the present invention provides a BODIPY-based near-infrared heavy atom-free photosensitizer and a preparation method and application. Such molecules have low dark toxicity, high reactive oxygen generation capacity under near-infrared light excitation, high photostability, high photothermal conversion efficiency and photothermal stability, and can significantly increase the applicability of photodynamic agents.

[0005] In a first aspect of the present invention, there is provided a BODIPY-based near-infrared heavy atom-free photosensitizer having a structure as shown in formula (I):

[0006]

[0007] in:

[0008] R1 is a substituted or unsubstituted C6-C10 aryl group;

[0009] R2 and R3 are each independently one of hydrogen, substituted or unsubstituted C6-C24 aryl, substituted or unsubstituted C3-C30 heteroaryl, and substituted or unsubstituted C6-C30 arylamine.

[0010] According to a specific embodiment of the present invention, R1 is a phenyl group substituted by a C1-C3 alkyl group, preferably a 2,4,6-trimethylphenyl group.

[0011] According to a specific embodiment of the present invention, R2 and R3 are each independently one of hydrogen, C6-C14 aryl, C4-C10 heteroaryl, C4-C10 heteroaryl substituted by C1-C6 alkyl, C10-C20 heteroaryl substituted by C6-C10 aryl, and C6-C18 arylamine; preferably one of hydrogen, phenyl, thienyl, dithienyl, dithienyl, benzothienyl, pyrrolidinyl, pyrrolidinyl substituted by C1-C6 alkyl, phenylthienyl, and triphenylamine.

[0012] According to a specific embodiment of the present invention, the photosensitizer is selected from any one of the structures shown in 1 to 10 below:

[0013]

[0014] The second aspect of the present invention provides a nanoparticle comprising the aforementioned photosensitizer.

[0015] The third aspect of the present invention provides the use of the aforementioned photosensitizer or nanoparticles in the preparation of photodynamic and photothermal combined therapy drugs for tumor tissue. Specifically, when the concentration of the photosensitizer compound is 0-1 mol / L, it can produce reactive oxygen species under irradiation with light of 600-1000 nm wavelength. The photosensitizer compound of the present invention overcomes the defects of photosensitizer molecules of similar structures in the prior art that need to introduce heavy atoms, allowing the photodynamic molecule to have less dark toxicity while producing sufficient reactive oxygen species.

[0016] In a fourth aspect of the present invention, a method for preparing the aforementioned photosensitizer is provided, comprising: a first reaction of a compound represented by formula A with copper halide to obtain a compound represented by formula A-1; a second reaction of the compound represented by formula A-1 with trans-(tributyltin)ethylene under an inert atmosphere to obtain a compound represented by formula B; a third reaction of the compound represented by formula B with copper halide to obtain a compound represented by formula B-1 or B-2; a fourth reaction of a compound represented by one of formulas B-1 or B-2 with at least one compound selected from an aromatic boronic acid compound, an aromatic organotin compound or a heterocyclic compound under an inert atmosphere to obtain a compound represented by formula (I), which is the aforementioned photosensitizer;

[0017] Wherein, X is a halogen, and R1 is a substituted or unsubstituted C6-C10 aryl group.

[0018] According to a specific embodiment of the present invention, the molar ratio of the compound represented by formula A to the copper halide is 1:5-15; the conditions of the first reaction include: the reaction solvent is acetonitrile, the reaction temperature is 75-85°C, and the reaction time is 1-3h.

[0019] According to a specific embodiment of the present invention, the molar ratio of the compound represented by formula A-1 to trans-(tributyltin)ethylene is 1:1-3; the conditions of the second reaction include: reacting in the presence of a palladium reagent and an organic phosphorus, the reaction solvent is toluene, or a mixed solvent of toluene and water, the reaction temperature is 80-120°C, and the reaction time is 0.5-2h; preferably, the palladium reagent is tris(dibenzylideneacetone)dipalladium, tetrakis(triphenylphosphine)palladium or tetrakis(triphenylphosphine)palladium; preferably, the organic phosphorus is tri(o-methylphenyl)phosphine.

[0020] According to a specific embodiment of the present invention, the molar ratio of the compound represented by formula B to the copper halide is 1:3-10; the conditions of the third reaction include: the reaction solvent is a mixed solvent of acetonitrile and dichloromethane, the reaction temperature is room temperature, and the reaction time is 1-3h; and / or, the molar ratio of the compound represented by one of formula B-1 or formula B-2 to a compound selected from an aromatic boronic acid compound, an aromatic organic tin compound or a heterocyclic compound is 1:1.5-3; the conditions of the fourth reaction include: reacting in the presence of a palladium reagent and a base, the reaction solvent is a mixed solvent of water and toluene, the reaction temperature is 100-120°C, and the reaction time is 1-3h; preferably, the palladium reagent is tris(dibenzylideneacetone)dipalladium, tetrakis(triphenylphosphine)palladium or tetrakis(triphenylphosphine)palladium.

[0021] The beneficial effects of the present invention are:

[0022] The present invention provides a series of new structural small molecule compound photosensitizers with BODIPY dimer as the basic skeleton and without heavy atoms. BODIPY dimer has an exciton coupling effect and has a significant ability to generate active oxygen. On this basis, different electron-donating and electron-withdrawing groups are introduced to form an electron "donor-acceptor-donor" (DAD) structure to form photosensitizer molecules. Such molecules have good stability and absorption spectrum in the near-infrared region, with a maximum absorption wavelength of 700-800nm, low dark toxicity, long triplet life, and high active oxygen generation ability under near-infrared light excitation. It overcomes the defects of similar photosensitizer molecules with short absorption wavelengths, and the introduction of heavy atoms to improve photosensitivity while significantly reducing triplet life and singlet oxygen yield in anoxic environments. Compared with the common photosensitizer molecule indocyanine green (ICG), it has lower dark toxicity and higher photostability, can significantly increase the applicability of photodynamic agents, and has a simple preparation method, high reaction efficiency, high yield, and good industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 For compound 2 1 H-NMR spectrum;

[0024] Figure 2 For compound 2 13 C-NMR spectrum;

[0025] Figure 3A is the normalized absorption spectrum of compound 2 in different solutions;

[0026] Figure 3B is the normalized fluorescence spectrum of compound 2 in different solutions under 750 nm excitation;

[0027] Figure 4A The dark toxicity test results of nanoparticles 2NPs on cells;

[0028] Figure 4B The dark toxicity test results of indocyanine green on cells;

[0029] Figure 5A Cytotoxicity test results for 4T1 cells stored in the dark and under laser irradiation;

[0030] Figure 5B The results of the cell phototoxicity test of nanoparticles 2NPs under laser irradiation;

[0031] Fig. 6A It is the ultraviolet absorption spectrum of the mixed toluene solution of compound 2 and 1,3-diphenylbenzisofuran changing with time under the condition of 808nm near-infrared light irradiation;

[0032] Figure 6Bis the fitted degradation spectrum of 1,3-diphenylbenzisofuran;

[0033] Fig. 7A is the UV absorption spectra of the aqueous solution of nanoparticle 2 at different times;

[0034] Figure 7B is a curve showing the absorbance of the aqueous solution of nanoparticle 2 changing with time;

[0035] Fig. 8A It is the fluorescence emission spectrum of the mixed aqueous solution of nanoparticle 2 and dichlorodihydrofluorescein changing with time under the condition of 808nm near-infrared light irradiation;

[0036] Figure 8B The ultraviolet absorption spectrum of the mixed aqueous solution of nanoparticle 2 and dichlorodihydrofluorescein changes with time under the condition of 808nm near-infrared light irradiation;

[0037] Fig.9A The photothermal heating curve of the DMSO solution of compound 2 changing with time under 808nm near-infrared light irradiation;

[0038] Fig. 9B It is a negative natural logarithm graph of the cooling time and the temperature in the cooling stage of the DMSO solution of compound 2 under 808nm near-infrared light irradiation;

[0039] Fig. 10A is the photothermal heating curve of the aqueous solution of nanoparticle 2 changing with time under 808nm near-infrared light irradiation;

[0040] Fig. 10B It is the negative natural logarithm graph of cooling time and temperature in the cooling stage of the aqueous solution of nanoparticles 2 under 808nm near-infrared light irradiation;

[0041] Fig.11A is the photothermal heating curve of the aqueous solution of ICG NPs under 808nm near-infrared light irradiation with time;

[0042] Fig. 11B It is the negative natural logarithm graph of the cooling time and the temperature in the cooling stage of the aqueous solution of ICG NPs under 808nm near-infrared light irradiation;

[0043] Fig. 12A The photothermal heating curves of ICG and 2NPs under 808 nm near-infrared light irradiation over time;

[0044] Fig. 12B This is the absorption spectrum of 2NPs before and after multiple 808nm near-infrared light irradiation. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Example 1 Synthesis of Compound 1

[0047] (1) Synthesis of Compound A

[0048]

[0049] Add 250 mL of water to a round-bottom flask, quickly add 6 mL of mesityleneformaldehyde, 8 mL of pyrrole, and 10 mL of 1 mol / L hydrochloric acid, stir at room temperature for 36 h, and then filter to obtain a black filter cake, which is the compound mesitylenedipyrromethene.

[0050] In a round-bottom flask, 3 g of isotrimethyldipyrromethene and 3 g of dichlorodicyanobenzoquinone (DDQ) were added, and 10 mL of triethylamine was added to dissolve the mixture. The mixture was stirred at room temperature for 1 h. Under ice bath conditions, 15 mL of boron trifluoride ether complex was added and the organic solvent was removed by vacuum distillation. After silica gel column chromatography, 2-3 g of a red solid was obtained, which was compound A.

[0051] (2) Synthesis of Compound A1

[0052]

[0053] In a round-bottom flask, add compound A (310 mg, 1 mmol, 1.0 eq), copper chloride dihydrate (1700 mg, 10 mmol, 10.0 eq), and acetonitrile (20.0 mL) respectively, and react at 80 ° C for 2 h. After the reaction solution is cooled to room temperature, pour the reaction solution into dichloromethane (30 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent is removed by vacuum distillation, and 150 mg of red solid is obtained by silica gel column chromatography, which is compound A-1.

[0054] (3) Synthesis of Compound B

[0055]

[0056] In a Shrek tube, add compound A-1 (69 mg, 0.2 mmol, 1.0 eq), tri(dibenzylideneacetone)dipalladium (6.9 mg), tri(o-methylphenyl)phosphine (9.0 mg), trans(tributyltin)ethylene (53 mL, 0.1 mmol, 0.5 eq), and 3 mL of toluene. React at 110°C for 1.5 h. After the reaction solution is cooled to room temperature, 60 mg of a blue solid is obtained by silica gel column chromatography, which is compound B.

[0057] (4) Synthesis of Compound B1

[0058]

[0059] In a round-bottom flask, compound B (644 mg, 1 mmol, 1.0 eq), cupric chloride dihydrate (1700 mg, 10 mmol, 10.0 eq), and CH3CN / DCM mixed solvent (V / V=1:1, 200.0 mL) were added respectively and reacted at room temperature for 2 h. The reaction solution was poured into water (250 mL) and rinsed with water (3×100 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 300 mg of a blue solid was obtained by silica gel column chromatography, which was compound B-1.

[0060] (5) Synthesis of Compound 1

[0061]

[0062] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq), 4-boric acid triphenylamine (58 mg, 0.2 mmol, 2.0 eq), tetrakis(triphenylphosphine)palladium (12 mg, 0.01 mmol, 1.0 eq), and add toluene (5.0 mL), water (1 mL), and sodium carbonate (32 mg, 0.3 mmol, 3.0 eq) after excluding air. React at 110 ° C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 25 mg of blue-black solid was obtained by silica gel column chromatography, which is compound 1. 1H NMR(400MHz,Chloroform-d)δ7.98(d,J=8.7Hz,2H),7.91(d,J=16.2Hz,1H),7.7 9(t,J=8.1Hz,2H),7.36–7.28(m,4H),7.21(dd,J=7.5,1.8Hz,4H),7.14–7.07(m, 6H),6.97(d,J=3.6Hz,4H),6.71(d,J=4.5Hz,1H),6.65(d,J=4.6Hz,2H),6.54(t, J=4.3Hz,2H),6.43(dd,J=4.1,2.0Hz,1H),2.37(s,6H),2.13(d,J=16.1Hz,12H).

[0063] Example 2 Synthesis of Compound 2

[0064] Preparation steps of compound 2 (1) (2) (3) are prepared according to Example 1

[0065] (4) Synthesis of Compound B2

[0066]

[0067] In a round-bottom flask, compound B (644 mg, 1 mmol, 1.0 eq), cupric chloride dihydrate (1700 mg, 10 mmol, 10.0 eq), and CH3CN / DCM mixed solvent (V / V=1:1, 200.0 mL) were added respectively and reacted at room temperature for 2 h. The reaction solution was poured into water (250 mL) and rinsed with water (3×100 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 250 mg of a blue solid was obtained by silica gel column chromatography, which was compound B2.

[0068] (5) Synthesis of Compound 2

[0069]

[0070] In a Shrek tube, compound B2 (35 mg, 0.1 mmol, 1.0 eq), 4-boric acid triphenylamine (116 mg, 0.4 mmol, 4.0 eq), tetrakis(triphenylphosphine)palladium (12 mg, 0.01 mmol, 0.1 eq), sodium carbonate (32 mg, 0.3 mmol, 3.0 eq) were added respectively, and toluene (5.0 mL) and water (1 mL) were added after exhausting the air, and the mixture was reacted at 110°C for 2 h. The reaction solution was poured into dichloromethane (50 mL) and rinsed with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 23 mg of a blue-black solid was obtained by silica gel column chromatography, which was compound 2. 1H NMR (400MHz, CDCl3) δ7.95(d,J=8.9Hz,4H),7.81(s,2H),7.34-7.27(m,8H),7.20(d,J=7.4Hz,8H),7.12-7.05(m, 10H), 6.96 (s, 4H), 6.66 (d, J = 4.3Hz, 2H), 6.59 (d, J = 4.4Hz, 2H), 6.51 (d, J = 4.5Hz, 2H), 2.37 (s, 6H), 2.15 (s, 12H).

[0071] Example 3 Synthesis of Compound 3

[0072] Preparation steps of compound 3 (1) (2) (3) (4) are prepared according to Example 1

[0073] (5) Synthesis of Compound 3

[0074]

[0075] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq), tributyl (2-thienyl) tin (44 mg, 0.15 mmol, 1.5 eq), tri(dibenzylideneacetone) dipalladium (4.6 mg, 0.01 mmol, 0.1 eq), tri(o-methylphenyl)phosphine (6 mg, 0.03 mmol, 0.3 eq) respectively, and add toluene (5.0 mL) after exhausting the air. React at 110 ° C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 31 mg of blue-black solid was obtained by silica gel column chromatography, which is compound 3. 1 H NMR(600MHz, CDCl3) δ8.29(dd,J=3.9,1.0Hz,1H),7.94(d,J=16.2Hz,1H),7.84(d,J=18.0Hz ,2H),7.53(dd,J=5.0,1.0Hz,1H),7.23(dd,J=5.0,3.9Hz,1H),7.12(d,J=4.6Hz,1H),7.10(d ,J=4.5Hz,1H),6.97(s,4H),6.79(d,J=4.4Hz,1H),6.69(d,J=4.6Hz,1H),6.61(d,J=4.4Hz,1 H), 6.58 (t, J = 3.7Hz, 2H), 6.45 (dd, J = 4.1, 1.9Hz, 1H), 2.37 (s, 6H), 2.13 (d, J = 12.4Hz, 12H).

[0076] Example 4 Synthesis of Compound 4

[0077] Preparation steps of compound 4 (1) (2) (3) (4) Prepare according to Example 2

[0078] (5) Synthesis of Compound 4

[0079]

[0080] In a Shrek tube, compound B-2 (35 mg, 0.1 mmol, 1.0 eq), tributyl(2-thienyl)tin (87 mg, 0.3 mmol, 3 eq), tri(dibenzylideneacetone)dipalladium (9.2 mg, 0.02 mmol, 0.2 eq), and tri(o-methylphenyl)phosphine (12 mg, 0.06 mmol, 0.6 eq) were added respectively, and toluene (5.0 mL) was added after the air was expelled.

[0081] The reaction mixture was reacted at 110°C for 2 h. The reaction solution was poured into dichloromethane (50 mL) and rinsed with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by distillation under reduced pressure, and 32 mg of a black solid was obtained by silica gel column chromatography, which was compound 4. 1 HNMR(600MHz, CDCl3)δ8.27(d,J=3.8Hz,2H),7.90(s,2H),7.50(d,J=5.0Hz,2H),7.22(dd,J=5.1,3.8Hz,2H), 7.13(d,J=4.5Hz,2H),6.97(s,4H),6.76(d,J=4.4Hz,2H),6.58(t,J=4.7Hz,4H),2.38(s,6H),2.15(s,12H).

[0082] Example 5 Synthesis of Compound 5

[0083] Preparation steps of compound 5 (1) (2) (3) (4) are prepared according to Example 1

[0084] (5) Synthesis of Compound 5

[0085]

[0086] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq) and 2,4-dimethyl-3-ethylpyrrole (300 μL) respectively, expel the air and add toluene (5.0 mL). React at 80 °C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, remove the organic solvent by vacuum distillation, and obtain 23 mg of blue-black solid by silica gel column chromatography, which is compound 6. 1H NMR(600MHz,Chloroform-d)δ10.18(t,J=11.2Hz,1H),8.01–7.97(m,1H),7.76(d,J=16.2Hz,1H),7.67(d,J=16. 1Hz, 1H), 6.97 (d, J = 4.3Hz, 1H), 6.94 (d, J = 4.5Hz, 1H), 6.88 (d, J = 6.3Hz, 5H), 6.83 (d, J = 4.7Hz, 1H), 6.52 (d, J = 4. 7Hz,1H),6.44(dd,J=10.3,4.3Hz,2H),6.33(d,J=4.3Hz,1H),6.27(d,J=4.3Hz,1H),2.37(q,J=7.6Hz,2H),2.31( s,3H),2.29(d,J=3.6Hz,7H),2.24(s,3H),2.10(d,J=7.0Hz,2H),2.05(d,J=6.8Hz,12H),1.00(t,J=7.6Hz,3H),.

[0087] Example 6 Synthesis of Compound 6

[0088] Preparation steps of compound 6 (1) (2) (3) (4) Prepare according to Example 1

[0089] (5) Synthesis of Compound 6

[0090]

[0091] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq), phenylboronic acid (20 mg, 0.15 mmol, 1.5 eq), tetrakis(triphenylphosphine)palladium (5.8 mg) respectively, expel the air, add toluene (5.0 mL), water (1 mL), sodium carbonate (32 mg, 0.3 mmol, 3.0 eq). React at 110 °C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, remove the organic solvent by vacuum distillation, and obtain 25 mg of blue-black solid by silica gel column chromatography, which is compound 7. 1 H NMR (600MHz, CDCl3) δ8.01–7.97(m,2H),7.87(d,J=16.3Hz,1H),7.83(d,J=

[0092] 10.4Hz,2H),7.52–7.47(m,3H),7.09(d,J=4.6Hz,1H),7.06(d,J=4.6Hz,1H),6.98(s,2H),6.96(s,2H),6.67(d,J=4.3Hz,1H),6.65(d,J= 4.6Hz, 1H), 6.62 (t, J = 5.0Hz, 2H), 6.58 (d, J = 4.1Hz, 1H), 6.44 (dd, J = 4.1, 1.9Hz, 1H), 2.38 (s, 3H), 2.37 (s, 3H), 2.17 (s, 6H), 2.11 (s, 6H).

[0093] Example 7 Synthesis of Compound 7

[0094] Preparation steps of compound 7 (1) (2) (3) (4) Prepare according to Example 2

[0095] (5) Synthesis of Compound B-1-7

[0096]

[0097] In a Shrek tube, add compound B-2 (35 mg, 0.1 mmol, 1.0 eq), phenylboronic acid (13 mg, 0.1 mmol, 1 eq), tetrakis(triphenylphosphine)palladium (12 mg, 0.01 mmol, 1.0 eq) respectively, and then add toluene (5.0 mL), water (1 mL), and sodium carbonate (32 mg, 0.3 mmol, 3.0 eq) after exhausting the air. React at 110 °C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, remove the organic solvent by vacuum distillation, and obtain 10 mg of blue-black solid by silica gel column chromatography, which is compound B-1-8.

[0098] (6) Synthesis of Compound 7

[0099]

[0100] In a Shrek tube, add compound B-1-8 (38 mg, 0.1 mmol, 1.0 eq), tributyl (2-thienyl) tin (44 mg, 0.15 mmol, 1.5 eq), tri (dibenzylideneacetone) dipalladium (4.6 mg, 0.01 mmol, 0.1 eq), tri (o-methylphenyl) phosphine (6 mg, 0.03 mmol, 0.3 eq) respectively. After exhausting the air, add toluene (5.0 mL). React at 110 ° C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation. After silica gel column chromatography, 37 mg of blue-black solid was obtained, which is compound 8.1 H NMR (600MHz, CDCl3) δ8.28–8.24(m,1H),7.98(dt,J=6.3,1.4Hz,2H),7.89(d,J=16.3Hz,1H),7 .83(d,J=16.2Hz,1H),7.52–7.44(m,4H),7.21(dd,J=5.1,3.8Hz,1H),7.12(d,J=4.6Hz,1H),7. 08(d,J=4.6Hz,1H),6.97(d,J=14.0Hz,4H),6.76(d,J=4.4Hz,1H),6.63(t,J=4.1Hz,2H),6.58( dd,J=9.9,4.3Hz,2H),6.55(d,J=4.5Hz,1H),2.38(d,J=10.5Hz,6H),2.18(s,6H),2.13(s,6H).

[0101] Example 8 Synthesis of Compound 8

[0102] Preparation steps of compound 8 (1) (2) (3) (4) Prepare according to Example 1

[0103] (5) Synthesis of Compound 8

[0104]

[0105] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq), tributyl (2-thienyl) tin (43 mg, 0.15 mmol, 1.5 eq), tri(dibenzylideneacetone) dipalladium (4.6 mg, 0.01 mmol, 0.1 eq), tri(o-methylphenyl)phosphine (6 mg, 0.03 mmol, 0.3 eq) respectively, and add toluene (5.0 mL) after exhausting the air. React at 110 ° C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 32 mg of black solid was obtained by silica gel column chromatography, which is compound 9. 1H NMR(600MHz, CDCl3)δ8.30(d,J=4.0Hz,1H),7.97(d,J=16.2Hz,1H),7.88–7.81(m,2H),7.68(d,J=7 .7Hz,2H),7.45(d,J=4.1Hz,1H),7.41(t,J=7.6Hz,2H),7.33(t,J=7.4Hz,1H),7.14(d,J=4.6Hz,1H) ,7.11(d,J=4.5Hz,1H),6.99-6.95(m,4H),6.83(d,J=4.5Hz,1H),6.70(d,J=4.6Hz,1H),6.62(d,J=4 .5Hz, 1H), 6.57 (d, J = 4.2Hz, 2H), 6.44 (dd, J = 4.1, 1.9Hz, 1H), 2.37 (s, 6H), 2.14 (d, J = 13.7Hz, 12H).

[0106] Example 9 Synthesis of Compound 9

[0107] Preparation steps of compound 9 (1) (2) (3) (4) Prepare according to Example 1

[0108] (5) Synthesis of Compound 9

[0109]

[0110] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq), 2,2'-bithiophene-5-boric acid (63 mg, 0.15 mmol, 1.5 eq), tetrakis(triphenylphosphine)palladium (6 mg) respectively, expel the air, add toluene (5.0 mL), water (1 mL), sodium carbonate (32 mg, 0.3 mmol, 3.0 eq). React at 110 ° C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 29 mg of blue-black solid was obtained by silica gel column chromatography, which is compound 11. 1H NMR(600MHz, CDCl3)δ8.14(d,J=4.1Hz,1H),7.88(d,J=16.2Hz,1H),7.80–7.73(m,2H), 7.23–7.19(m,3H),7.06(d,J=4.6Hz,1H),7.03(d,J=4.5Hz,1H),6.97(dd,J=5.1,3.6Hz, 1H),6.89(s,4H),6.71(d,J=4.4Hz,1H),6.61(d,J=4.6Hz,1H),6.53(d,J=4.5Hz,1H),6 .49(d,J=4.2Hz,2H),6.36(dd,J=4.1,1.9Hz,1H),2.29(s,6H),2.05(d,J=10.7Hz,12H).

[0111] Example 10 Synthesis of Compound 10

[0112] Preparation steps of compound 10 (1) (2) (3) (4) are prepared according to Example 1

[0113] (5) Synthesis of Compound 10

[0114]

[0115] In a Shrek tube, add compound B-1 (35 mg, 0.1 mmol, 1.0 eq), (thieno[3,2-B]thiophene-2-yl) tributyltin (64 mg, 0.15 mmol, 1.5 eq), tri(dibenzylideneacetone)dipalladium (4.6 mg, 0.01 mmol, 0.1 eq), tri(o-methylphenyl)phosphine (6 mg, 0.03 mmol, 0.3 eq) respectively. After exhausting the air, add toluene (5.0 mL). React at 110 ° C for 2 h. Pour the reaction solution into dichloromethane (50 mL) and rinse with water (3×50 mL). After drying with anhydrous sodium sulfate, the organic solvent was removed by vacuum distillation, and 26 mg of black solid was obtained by silica gel column chromatography, which is compound 12. 1H NMR(600MHz, CDCl3)8.55(s,1H),7.97(d,J=16.2Hz,1H),7.87(d,J=16.2Hz,1H),7.83(s,1 H),7.52(d,J=5.2Hz,1H),7.26(d,J=5.2Hz,1H),7.17(d,J=4.6Hz,1H),7.12(d,J=4.5Hz,1 H),6.97(d,J=2.0Hz,4H),6.81(d,J=4.4Hz,1H),6.70(d,J=4.6Hz,1H),6.61(d,J=4.5Hz,1 H),6.61–6.56(m,2H),6.45(dd,J=4.1,1.9Hz,1H),2.37(s,6H),2.14(d,J=14.3Hz,12H).

[0116] Example 11 Nanoparticle Preparation

[0117] Compound 2 (1 mg) and poloxamer F127 (100 mg) were weighed and dissolved in 5 mL of chloroform. A blue-black drug film was obtained by spin drying using a round-bottom flask. The round-bottom flask was heated to 70-80 ° C, 1 mL of PBS buffer was added and stirred rapidly to obtain a black suspension. After freeze-drying, a black powder was obtained, which is nanoparticle 2NPs, which can be used for photodynamic and photothermal combined therapy of tumor tissues.

[0118] Test Example 1 Basic Spectra of the Compounds of the Invention

[0119] This test example tests the absorption spectrum and fluorescence spectrum of the compound 2 of the present invention in various solvents. Figure 3A Normalized absorption spectra of compound 2 in different solutions. Figure 3B Normalized fluorescence spectra of compound 2 in different solutions under excitation at 750 nm.

[0120] Test Example 2 Dark toxicity of the compounds of the present invention to cells

[0121] In this test example, indocyanine green (ICG) was used as a positive control, and the CCK-8 method was used to evaluate the cytotoxicity of the nanoparticles 2NPs of the present invention at different concentrations on the mouse breast cancer cell line 4T1 in a dark environment. The test results are shown in Figure 4A , 4B .

[0122] Depend on Figure 4A , 4B The data show that nanoparticles 2NPs have lower dark toxicity and better biocompatibility than ICG at higher concentrations (≥30μM).

[0123] Experimental Example 3 Phototoxicity of the Compounds of the Invention to Cells

[0124] This experiment shows the photocytotoxicity of nanoparticles 2NPs by CCK-8 assay. 4T1 cells were kept in the dark (black) or irradiated with 808 nm laser for 10 min (red, 0.84 W cm -2 ). Test results are shown in Figure 5A , 5B .

[0125] Depend on Figure 5A , 5B The data show that the IC of nanoparticles 2NPs is 10 min under continuous 808 nm laser irradiation. 50 It is 15.4μM.

[0126] Test Example 4 Active oxygen generating ability of the compounds of the present invention

[0127] Weigh compound 2 (1-1.5 mg) and dissolve it in 2 mL of dichloromethane; then weigh 1,3-diphenylbenzisofuran (3-3.5 mg) and dissolve it in 2 mL of dichloromethane; then dilute with toluene to a molar concentration of 10 -5 mol / L (target compound) and 10 -5 mol / L (1,3-diphenylbenzisofuran) mixed solution, then irradiated with 808nm near-infrared light for 210s, tested the absorption spectrum every 30s, and observed the changes in the absorption signal corresponding to 1,3-diphenylbenzisofuran. The test results are shown in Fig. 6A , 6B .

[0128] Depend on Fig. 6A , 6B The data show that 1,3-diphenylbenzisofuran (416nm) continues to decrease, indicating that the compound of formula A can continuously produce active oxygen under 808nm wavelength light, and the degradation spectrum of 1,3-diphenylbenzisofuran was fitted based on this.

[0129] Test Example 5 Stability of the Nanoparticles of the Present Invention in Water

[0130] Weigh an appropriate amount of nanoparticles 2NPs and dissolve them in water, seal and store them, and measure their UV absorption spectra on days 0, 2, 4, 6, 8, 10, and 20. Record the changes in absorbance at the wavelength with the highest absorption and draw a curve. The test results are shown in Fig. 7A , 7B .

[0131] Depend on Fig. 7A , 7B The data show that there is still a large amount of nanoparticles 2NPs remaining in water after 20 days, indicating that nanoparticles 2NPs have good stability in water and can exist stably for a long time.

[0132] Test Example 6 Active oxygen generation ability of the nanoparticles of the present invention in water

[0133] Weigh 1 mg of 2NPS nanoparticles and dissolve them in 1 mL of water. Take an appropriate amount of solution and dilute it to 3 mL so that its absorbance at 808 nm is about 0.15 Abs. Add an appropriate amount of DCFH and use an optical power of 0.7 W cm -2 The UV absorption spectrum and fluorescence emission spectrum were recorded and plotted every 30 seconds. The test results are shown in Fig. 8A , 8B .

[0134] Depend on Fig. 8A , 8B The data show that the curve indicates that the nanoparticle 2NPS can stably produce reactive oxygen after 808nm laser irradiation and can be used as a potential photodynamic therapy drug.

[0135] Test Example 7 Photothermal performance test of the compound of the present invention

[0136] A DMSO solution of compound 2 with a concentration of 30 μM, an aqueous solution of 2NPS, and an aqueous solution of ICG were prepared, and an optical power of 0.97 W cm -2 ,808nm laser irradiation, measuring and recording its temperature every 20s, drawing the photothermal heating curve and the negative natural logarithm graph of cooling time and temperature in the cooling stage. The test results are shown in Fig.9A , 9B , 10A, 10B, 11A, 11B.

[0137] Depend on Fig.9A , 9B The data show that the photothermal conversion efficiency of 2 in DMSO is 66.2%. Fig. 10A , 10B The data show that the photothermal conversion efficiency of 2NPS in water is 69.4%. Fig.11A , 11B The data show that the photothermal conversion efficiency of ICG NPs in water is 28.5%. Compound 2 and its nanoparticles 2NPs have higher photothermal conversion efficiency than ICG.

[0138] A 30 μM aqueous solution of 2NPs was prepared using a light power of 0.97 W cm -2 ,808nm laser irradiation for a period of time, then stop irradiation and let it cool to room temperature, repeat several times, the test results are shown in Fig. 12A , 12B .

[0139] Depend on Fig. 12A , 12BThe data show that the heating curve of 2NPs has no obvious attenuation and has better photothermal stability than ICG.

[0140] The above results indicate that the photosensitizer has high photothermal conversion efficiency and high photothermal stability, and can be used as a potential photothermal therapy drug.

[0141] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

Claims

1. A BODIPY-based near-infrared heavy-atom-free photosensitizer, characterized in that: It has the structure shown in 2 below: 。 2. A nanoparticle, characterized in that: The nanoparticles contain the photosensitizer according to claim 1.

3. Use of the photosensitizer according to claim 1 or the nanoparticles according to claim 2 in the preparation of drugs for photodynamic and photothermal combined therapy of tumor tissues.

4. A method for preparing the photosensitizer according to claim 1, characterized in that: The preparation method comprises: The compound represented by formula A is subjected to a first reaction with copper halide to obtain a compound represented by formula A-1; Under an inert atmosphere, the compound represented by formula A-1 is subjected to a second reaction with trans-(tributyltin)ethylene to obtain a compound represented by formula B; The compound represented by formula B is subjected to a third reaction with copper halide to obtain a compound represented by formula B-2; Under an inert atmosphere, the compound represented by formula B-2 is subjected to a fourth reaction with 4-triphenylamine borate to obtain a compound represented by formula (I), which is the photosensitizer; Wherein, X is halogen and R1 is 2,4,6-trimethylphenyl.

5. The preparation method according to claim 4, characterized in that: The molar ratio of the compound represented by formula A to copper halide is 1:5-15; the conditions of the first reaction include: the reaction solvent is acetonitrile, the reaction temperature is 75-85°C, and the reaction time is 1-3 h.

6. The preparation method according to claim 4, characterized in that: The molar ratio of the compound represented by formula A-1 to trans-(tributyltin)ethylene is 1:1-3; the conditions of the second reaction include: reacting in the presence of a palladium reagent and an organic phosphorus, the reaction solvent is toluene, or a mixed solvent of toluene and water, the reaction temperature is 80-120°C, and the reaction time is 0.5-2h.

7. The preparation method according to claim 6, characterized in that: The palladium reagent is tris(dibenzylideneacetone)dipalladium or tetrakis(triphenylphosphine)palladium.

8. The preparation method according to claim 6, characterized in that: The organic phosphorus is tri(o-methylphenyl)phosphine.

9. The preparation method according to claim 4, characterized in that: The molar ratio of the compound represented by formula B to the copper halide is 1:3-10; the conditions of the third reaction include: the reaction solvent is a mixed solvent of acetonitrile and dichloromethane, the reaction temperature is room temperature, and the reaction time is 1-3 h; and / or, The molar ratio of the compound represented by formula B-2 to 4-triphenylamine borate is 1:1.5-3; the conditions of the fourth reaction include: reacting in the presence of a palladium reagent and a base, the reaction solvent is a mixed solvent of water and toluene, the reaction temperature is 100-120°C, and the reaction time is 1-3 h.

10. The preparation method according to claim 9, characterized in that: The palladium reagent is tris(dibenzylideneacetone)dipalladium or tetrakis(triphenylphosphine)palladium.

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