BODIPY dye with annular structure as well as preparation method and application of BODIPY dye

Abstract

The invention discloses a BODIPY dye with an annular structure as well as a preparation method and application thereof, relates to the technical field of medical dyes, and solves the problems of stability of the BODIPY dye in an aqueous medium and safety in a living body. The preparation method comprises the following steps: dissolving a compound A and dicarboxylic acid in anhydrous dichloromethane, adding 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and a catalyst, carrying out a reaction under the protection of nitrogen, and carrying out silica gel column chromatography purification on a crude product to obtain the BODIPY dye with the cyclic structure. The amphipathy of the cyclic BODIPY formed by ester bonds or ether bonds is increased, so that the cyclic BODIPY forms nanoparticles in an aqueous solution, the BODIPY photosensitizer is delivered in a living body, the stability of the BODIPY photosensitizer in water is enhanced, the in-vivo circulation time is prolonged, the safety of the BODIPY photosensitizer in the living body is improved, and the integration of tumor diagnosis and treatment in the living body can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of medical dyes, and in particular to a BODIPY dye with a ring structure and a preparation method and application thereof. Background Art

[0002] BODIPY dyes, the full name of which is Boron-Dipyrromethene, are a class of organic dyes with special optical properties. Their molecular structure consists of two pyrrole rings connected by a quaternary boron bridge. BODIPY dyes have been widely used in biomarkers, photodynamic therapy (PDT), photothermal therapy (PTT) and fluorescence imaging due to their excellent optical properties, such as high quantum yield, good photostability, wide absorption band and narrow emission band.

[0003] However, most BODIPY dyes are hydrophobic and insoluble in biological media, which hinders their biomedical applications to some extent. One way to solve this problem is to prepare highly stable BODIPY water-dispersible nanoparticles (BODIPY NPs). The traditional method of preparing fluorescent nanoparticles is usually to physically encapsulate or chemically bond the dye to a polymer matrix or other nanoparticles. However, these methods have many problems. For example, due to the leakage of dyes from nanoparticles over time, the effective concentration of dyes at the tumor site may be insufficient, thereby reducing the efficacy of photodynamic therapy (PDT); due to the potential toxicity of the carrier, it causes damage to normal tissues and increases side effects during treatment; or due to batch-to-batch differences in the complex preparation process, the performance is unstable, affecting the consistency and predictability of the treatment effect.

[0004] Therefore, in the study of integrated diagnosis and treatment of tumors using BODIPY dye as photosensitizer-mediated photodynamic and photothermal therapy, its stability in aqueous media and safety in vivo are the key to this study. Summary of the invention

[0005] In order to improve the stability of BODIPY dye in water medium and the safety problem in organisms, the present invention provides a BODIPY dye with a ring structure and a preparation method and application thereof.

[0006] The technical solution of the present invention is as follows:

[0007] A BODIPY dye with a ring structure, the structural formula is as follows:

[0008]

[0009] Wherein, R1 is selected from H or CH3; R2 is selected from H, I or Br; R3 is selected from H, CH3 or C6H5; R4 is selected from

[0010] The present invention also provides a method for preparing a BODIPY dye having a ring structure, comprising dissolving a compound A and a dicarboxylic acid in anhydrous dichloromethane, adding 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and a catalyst, reacting under nitrogen protection, and purifying the crude product by silica gel column chromatography to obtain a BODIPY dye having a ring structure;

[0011] The structural formula of the compound A is as follows:

[0012]

[0013] Preferably, the dicarboxylic acid is selected from HOOC(C4H8)COOH, HOOCCH2S-SCH2COOH, HOOCCH2PhCH2COOH or HOOCCH2(OCH2CH2) n OCH2COOH;

[0014] Among them is HOOCCH2(OCH2CH2) n OCH2COOH is selected from polyethylene glycol derivatives of different molecular weights, and has different molecular weights, including 200, 400, 600, 800, 1000 Daltons and the like.

[0015] Preferably, the catalyst is 4-dimethylaminopyridine.

[0016] Preferably, the molar ratio of the compound A, dicarboxylic acid and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is 0.123:0.148:0.37.

[0017] Preferably, the reaction temperature is room temperature and the reaction time is 24 hours.

[0018] The present invention also provides an application of the BODIPY dye having a ring structure, specifically: application as a photosensitizer in the integrated diagnosis and treatment research of tumors using photodynamic and photothermal therapy.

[0019] Compared with the prior art, the specific beneficial effects of the present invention are:

[0020] The cyclic BODIPY formed by ester bonds or ether bonds of the present invention increases its amphiphilicity, making it very easy to self-assemble in aqueous solution to form nanoparticles with high stability. It can achieve in vivo delivery, enhance stability in water, prolong in vivo circulation time, increase its biocompatibility and safety in vivo, and realize its integration of tumor diagnosis and treatment in vivo.

[0021] The BODIPY dye provided by the present invention has a concise and clear structure, a simple synthesis method, and a low production cost; the BODIPY photosensitizer has a high molar extinction coefficient and has the advantage of adjustable spectrum. Due to the strong absorption in the visible light range, the requirements for the excitation light source are reduced, which is conducive to expanding the scope of clinical use of BODIPY photosensitizers and bringing higher social and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the H NMR spectrum of BODIPY-1;

[0023] Figure 2 is the electrospray ionization mass spectrum of BODIPY-1;

[0024] Figure 3 is the H NMR spectrum of BODIPY-2;

[0025] Figure 4 is the H NMR spectrum of BODIPY-4;

[0026] Figure 5 Matrix-assisted laser desorption time-of-flight mass spectrometry of BODIPY-4;

[0027] Figure 6 The toxicity graphs of BODIPY-2 nanoparticles to mouse breast cancer cells (4T1) under dark and light conditions (C, D) and to mouse normal fibroblasts (L929) under dark and light conditions (A, B);

[0028] Figure 7 The toxicity of BODIPY-3 nanoparticles to mouse breast cancer cells (4T1) under dark and light conditions;

[0029] Figure 8 The toxicity of BODIPY-4 nanoparticles to mouse breast cancer cells (4T1) under dark and light conditions. DETAILED DESCRIPTION

[0030] In order to make the technical solution of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the specification of the present invention. It should be noted that the following embodiments are only used to better understand the technical solution of the present invention and should not be understood as a limitation to the present invention.

[0031] Example 1.

[0032] In this example, compound A was synthesized by the following steps:

[0033] BODIPY (200 mg, 0.25 mmol) and p-hydroxybenzaldehyde (102 mg, 0.75 mmol) were dissolved in 30 mL of anhydrous DMF, acetic acid (100 μL) and piperidine (200 μL) were added, and the mixture was reacted at 80° C. for 20 min under nitrogen protection. The crude product was purified by silica gel column chromatography to obtain the product (Compound A).

[0034] Its synthetic route is as follows:

[0035]

[0036] Example 2.

[0037] In this example, BODIPY-1 is generated by reacting the compound A prepared in Example 1 with adipic acid in anhydrous dichloromethane.

[0038] The specific preparation process is as follows:

[0039] Compound A (100 mg, 0.123 mmol) and HOOC(C4H8)COOH (20 mg, 0.148 mmol) were dissolved in 50 mL of anhydrous dichloromethane, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl, 58 mg, 0.37 mmol) and 4-dimethylaminopyridine (DMAP, catalytic amount) were added, nitrogen was protected, and the reaction was carried out at room temperature for 24 h. The crude product was purified by silica gel column chromatography to obtain the product (BODIPY-1).

[0040] Its synthetic route is as follows:

[0041]

[0042] The H NMR spectrum of BODIPY-1 is shown in Figure 1 , electrospray ionization mass spectrometry results are shown in Figure 2 , which can prove the structure and purity of BODIPY-1.

[0043] Example 3.

[0044] In this example, BODIPY-2 is generated by reacting the compound A prepared in Example 1 with a dicarboxylic acid HOOCCH2S-SCH2COOH in anhydrous dichloromethane.

[0045] The specific preparation process is as follows:

[0046] Compound A (100 mg, 0.123 mmol) and HOOCCH2S-SCH2COOH (20 mg, 0.148 mmol) were dissolved in 50 mL of anhydrous dichloromethane, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl, 58 mg, 0.37 mmol) and 4-dimethylaminopyridine (DMAP, catalytic amount) were added, and the mixture was reacted at room temperature for 24 h under an inert gas atmosphere. The crude product was purified by silica gel column chromatography to obtain the product (BODIPY-2).

[0047] Its synthetic route is as follows:

[0048]

[0049] The H NMR spectrum of BODIPY-2 is shown in Figure 3 , the structure of BODIPY-2 can be proved.

[0050] Example 4.

[0051] In this example, BODIPY-3 is generated by reacting the compound A prepared in Example 1 with a dicarboxylic acid HOOCCH2PhCH2COOH in anhydrous dichloromethane.

[0052] The specific preparation process is as follows:

[0053] Compound A (100 mg, 0.103 mmol) and HOOCCH2PhCH2COOH (32 mg, 0.165 mmol) were dissolved in 50 mL of anhydrous dichloromethane, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl, 60 mg, 0.38 mmol) and 4-dimethylaminopyridine (DMAP, catalytic amount) were added, and the mixture was reacted at room temperature for 24 h under an inert gas atmosphere. The crude product was purified by silica gel column chromatography to obtain the product (BODIPY-3).

[0054] Its synthetic route is as follows:

[0055]

[0056] Example 5.

[0057] In this example, the compound A prepared in Example 1 and the dicarboxylic acid HOOCCH2(OCH2CH2) n OCH2COOH reacts in anhydrous dichloromethane to generate BODIPY-4.

[0058] The specific preparation process is as follows:

[0059] Compound A (40.6 mg, 0.05 mmol) and HOOCCH2 (OCH2CH2)n OCH2COOH (20 mg, 0.05 mmol) was dissolved in 50 mL of anhydrous dichloromethane, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl, 48 mg, 0.25 mmol) and 4-dimethylaminopyridine (DMAP, catalytic amount) were added, and the reaction was carried out at room temperature under an inert gas atmosphere for 48 hours. After the reaction was completed, the product (BODIPY-4) was purified by column chromatography.

[0060] Its synthetic route is as follows:

[0061]

[0062] The H NMR spectrum of BODIPY-4 is shown in Figure 4 , matrix-assisted laser desorption time-of-flight mass spectrometry Figure 5 , which can prove the structure and purity of BODIPY-4.

[0063] Effect example.

[0064] MTT assay was used to evaluate the antitumor activity of cyclic BODIPY-2:

[0065] Mouse breast cancer cells (4T1 cells) and fibroblasts (L929 cells) were inoculated in 96-well plates and cultured until the cells adhered to the wall. Different concentrations of BODIPY-2 nanoparticles (0-20 μM) were added to the culture dish, and each well was illuminated for 5 minutes after incubation for 4 hours, and then cultured for 24 hours, and then MTT (20 ml / well) was added. After 4 hours, the culture medium in each well was removed and DMSO (150 μL / well) was added. Finally, the cells were shaken for 3 minutes, and the absorbance at 492 nm was measured with an enzyme marker to calculate the relative survival rate of the cells. Each group of experiments was repeated at least three times.

[0066] The experimental results are shown in Figure 6 The results showed that under light-free conditions, BODIPY-1 and BODIPY-2 exhibited good biocompatibility; under light conditions, a lower concentration of BODIPY-2 (10 μM) could eliminate tumor cells without damaging normal cells.

[0067] The same procedure was used to evaluate the antitumor activity of cyclic BODIPY-3 and BODIPY-4. Figure 7 The cytotoxicity of BODIPY-3 under illumination and non-illumination conditions was studied. The results showed that it was basically non-toxic under non-illumination conditions, but under illumination conditions, it could kill tumor cells at 20 μM. Figure 8 The cytotoxicity of BODIPY-4 under illumination and non-illumination conditions was studied. The results showed that it was basically non-toxic under non-illumination conditions, but it could kill tumor cells at 60 nM under illumination conditions.

[0068] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A BODIPY dye having a ring structure, characterized in that: The structural formula is as follows: Wherein, R1 is selected from H or CH3; R2 is selected from H, I or Br; R3 is selected from H, CH3 or C6H5; R4 is selected from 2. A method for preparing a BODIPY dye having a ring structure, characterized in that: Dissolve compound A and dicarboxylic acid in anhydrous dichloromethane, add 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and a catalyst, react under nitrogen protection, and purify the crude product by silica gel column chromatography to obtain a BODIPY dye with a ring structure; The structural formula of the compound A is as follows:

3. The method for preparing the BODIPY dye having a ring structure according to claim 2, characterized in that: The dicarboxylic acid is selected from HOOC(C4H8)COOH, HOOCCH2S-SCH2COOH, HOOCCH2PhCH2COOH or HOOCCH2(OCH2CH2) n OCH2COOH.

4. The method for preparing the BODIPY dye having a ring structure according to claim 2, characterized in that: The catalyst is 4-dimethylaminopyridine.

5. The method for preparing the BODIPY dye having a ring structure according to claim 2, characterized in that: The molar ratio of the compound A, dicarboxylic acid and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is 0.123:0.148:0.

37.

6. The method for preparing the BODIPY dye having a ring structure according to claim 2, characterized in that: The reaction temperature is room temperature and the reaction time is 24 hours.

7. A use of the BODIPY dye having a ring structure as claimed in claim 1 or the BODIPY dye having a ring structure prepared by the preparation method according to any one of claims 2 to 6, characterized in that: It is used as a photosensitizer in the integrated diagnosis and treatment of tumors using photodynamic and photothermal therapy.

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