A pyrrolopyrozole derivative and its use

Abstract

The application discloses a D-A'-pi-A-pi-A'-D type diketopyrrolopyrrole derivative, which has the following structural general formula: The application provides a design and synthesis scheme of a D-A'-pi-A-pi-A'-D type diketopyrrolopyrrole derivative. 2000 By introducing an additional electron acceptor and a suitable pi bridge, a new type of small molecule photothermal agent with near-infrared region one absorption, near-infrared region two emission and high molar extinction coefficient is prepared. By wrapping the amphiphilic polymer DSPE-PEG

Description

Technical Field

[0001] This invention belongs to the field of biomedical engineering technology, specifically, it relates to a pyrrolopyrroledione derivative and its applications. Background Technology

[0002] Over the past few decades, cancer has become one of the most serious threats to human health. However, traditional treatments, including surgical resection, chemotherapy, and radiotherapy, cause immense suffering and severe side effects for patients. Therefore, the development of more efficient cancer treatments is urgently needed. As an emerging treatment method, photothermal therapy (PTT) utilizes photothermal agents to convert absorbed photon energy into heat energy to inhibit or ablate local tumors, and has rapidly developed due to its non-invasive nature and negligible drug resistance. To date, photothermal agents such as inorganic nanoparticles, organic small molecules, and organic polymers have been developed. Among them, organic small molecule photothermal agents have attracted much attention due to their excellent biocompatibility and well-defined structure. However, problems such as low molar extinction coefficient, poor photostability, and low photothermal conversion efficiency limit the further development of small molecule photothermal agents. Furthermore, small molecule photothermal agents with near-infrared II (NIR-II, 1000-1700 nm) emission can avoid interference from biological autofluorescence and reflect the photothermal treatment process in real time. However, there are currently few fluorescent dyes with strong near-infrared II fluorescence emission, and there is an urgent need to develop more high-performance dyes to achieve the goal of integrated tumor diagnosis and treatment.

[0003] Pyrrolopyrroledione derivatives possess advantages such as high molar extinction coefficients, good photostability, and easy structural modification, making them widely used in the development of small-molecule photothermal agents. Unfortunately, donor-acceptor-donor (DAD) type photothermal agents with pyrrolopyrroledione as the core have short absorption / emission wavelengths, making it difficult to meet the penetration depth requirements in in vivo experiments. Furthermore, the extremely strong hydrophobicity and overly planar structure of pyrrolopyrroledione derivatives pose a challenge of aggregation-induced quenching (ACQ) in in vivo fluorescence imaging. This strong intermolecular π-π interaction also restricts molecular vibrations, resulting in weak photoacoustic signals and low photothermal conversion efficiency. Therefore, developing novel pyrrolopyrroledione derivatives through rational molecular engineering strategies to simultaneously achieve strong near-infrared fluorescence / photoacoustic signals and high photothermal conversion efficiency is of great significance. Summary of the Invention

[0004] The first objective of this invention is to provide a novel pyrrolopyrrole dione derivative of the D-A'-π-A-π-A'-D type.

[0005] A second object of the present invention is to provide the use of the pyrrolopyrroledione derivative in the preparation of water-soluble nanoparticles for multimodal imaging-guided photothermal therapy.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a pyrrolopyrroledione derivative having the following general structural formula:

[0008]

[0009] The additional receptor is selected from one of the following structures:

[0010]

[0011] The π-bridge is selected from one of the following structures:

[0012]

[0013] m is selected from 0 to 10 (preferably 0, 1, 2, 3, 4, 5, 6, 7);

[0014] n is selected from 0 to 10 (preferably 0, 1, 2, 3, 4, 5, 6, 7).

[0015] Preferably, in the pyrrolopyrrole dione derivative, the π-bridge is selected from one of the following structures:

[0016]

[0017] Most preferably, the pyrrolopyrrole dione derivative is selected from one of the following structures:

[0018]

[0019]

[0020] A second aspect of the present invention provides the use of the pyrrolopyrroledione derivative in the preparation of water-soluble nanoparticles for multimodal imaging-guided photothermal therapy.

[0021] The application includes the following steps:

[0022] The pyrrolopyrrole dione derivative and the amphiphilic polymer DSPE-PEG are mixed in a mass ratio of 1:15 to 30 (preferably 1:20). 2000 The ultrasonic particles are dissolved in tetrahydrofuran solution. Under vigorous stirring, the prepared solution is slowly added dropwise to a weighing bottle containing deionized water. The mixture is stirred and dialyzed in deionized water for 1–24 hours to obtain stable nanoparticles, which are water-soluble nanoparticles used for multimodal imaging-guided photothermal therapy.

[0023] A third aspect of the present invention provides the use of the water-soluble nanoparticles described above for multimodal imaging-guided photothermal therapy in the preparation of a medicament for treating breast cancer.

[0024] In a fourth aspect, the present invention provides the use of the pyrrolopyrroledione derivative in the preparation of a photothermal agent for multimodal imaging guidance.

[0025] By adopting the above technical solution, the present invention has the following advantages and beneficial effects:

[0026] This invention proposes a design and synthesis scheme for a class of D-A'-π-A-π-A'-D type pyrrolopyrroledione derivatives. By introducing additional electron acceptors and suitable π-bridges, novel small-molecule photothermal agents with near-infrared I absorption, near-infrared II emission, and high molar extinction coefficients are prepared. This is achieved using the amphiphilic polymer DSPE-PEG. 2000 Encapsulated into water-soluble nanoparticles, enabling photothermal therapy of solid tumors guided by near-infrared fluorescence imaging (FLI), photoacoustic imaging (PAI), and photothermal imaging (PTI).

[0027] This invention achieves strong near-infrared I absorption and near-infrared II fluorescence emission by introducing additional electron acceptors and a π-bridge with appropriate steric hindrance, which can be used for near-infrared II fluorescence imaging, photoacoustic imaging, and photothermal imaging.

[0028] In this invention, the introduction of additional acceptors can broaden the absorption spectrum of the dye, increase its molar extinction coefficient, and enhance its photostability. The introduction of π-bridges with appropriate steric hindrance can not only effectively suppress intermolecular π-π interactions and improve fluorescence quantum yield, but also provide space for molecular vibrations, thereby enhancing the intensity of its photoacoustic signal.

[0029] In this invention, compared with alkyl chain-modified fluorene structures, alkyl chain-modified cyclofluorene-thiophene structural units are more suitable as electronic π-bridges to improve the photophysical properties of D-A'-π-A-π-A'-D type pyrrolopyrrole dione derivatives.

[0030] The pyrrolopyrrole dione derivative BDB prepared in this invention exhibits a high molar extinction coefficient (1.25 × 10⁻⁶) in the near-infrared region at 730 nm. 5 Lmol -1 cm -1 ).

[0031] The BDB NPs prepared by this invention exhibit strong near-infrared II fluorescence emission intensity under 808 nm excitation, and can be used for near-infrared II fluorescence imaging.

[0032] The BDB NPs prepared by this invention exhibit strong photoacoustic signals under 700 nm excitation and can be used for photoacoustic imaging.

[0033] The BDB NPs prepared by this invention have a high photothermal conversion efficiency (43.8%) and can be used for photothermal imaging and photothermal therapy.

[0034] The BDB NPs prepared by this invention have better photostability than the commercial photothermal agent indocyanine green (ICG), making them a superior photothermal formulation.

[0035] The BDB NPs prepared in this invention can induce apoptosis in breast cancer cells through photothermal therapy under 808nm laser irradiation, with the apoptotic cell rate reaching as high as 83.6%.

[0036] The BDB NPs prepared by this invention have good biocompatibility and do not cause damage to the major organs (heart, liver, spleen, lungs, and kidneys) of mice. They inhibit the proliferation of solid breast cancer tumors in mice through precise photothermal therapy. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the proton NMR spectrum of compound BDB (using deuterated chloroform as the solvent).

[0038] Figure 2 This is a schematic diagram of the carbon NMR spectrum of compound BDB (using deuterated chloroform as the solvent).

[0039] Figure 3 This is a schematic diagram of the time-of-flight mass spectra of compound BDB.

[0040] Figure 4 This is a schematic diagram of the proton NMR spectrum of compound KDK (using deuterated chloroform as the solvent).

[0041] Figure 5 This is a schematic diagram of the carbon NMR spectrum of compound KDK (using deuterated chloroform as the solvent).

[0042] Figure 6 This is a schematic diagram of the time-of-flight mass spectrometry spectrum of compound KDK.

[0043] Figure 7 This is a schematic diagram of the normalized ultraviolet absorption spectra of compound BDB (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the absorbance.

[0044] Figure 8This is a schematic diagram of the normalized ultraviolet absorption spectra of compound KDK (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the absorbance.

[0045] Figure 9 This is a schematic diagram of the normalized fluorescence emission spectra of compound BDB (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the normalized fluorescence intensity.

[0046] Figure 10 This is a schematic diagram of the normalized fluorescence emission spectra of compound KDK (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the normalized fluorescence intensity.

[0047] Figure 11 denoted as the molar extinction coefficient of compound BDB in DMSO solution, where: the horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the molar extinction coefficient.

[0048] Figure 12 denoted as the molar extinction coefficient of compound KDK in DMSO solution, where: the horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the molar extinction coefficient.

[0049] Figure 13 BDB NPs (20 μM) were subjected to continuous laser irradiation for 10 min (808 nm, 0.8 W cm⁻¹). -2 The diagram illustrates the light stability assessment, where the horizontal axis represents the illumination time (in minutes) and the vertical axis represents the absorbance.

[0050] Figure 14 In vitro near-infrared II fluorescence imaging of BDB NPs at different concentrations (0 μM, 10 μM, 20 μM, 40 μM, 80 μM) under 808 nm excitation and 1100 nm filter.

[0051] Figure 15 This is a schematic diagram of in vitro photoacoustic imaging of BDB NPs at different concentrations (0 μM, 20 μM, 40 μM, 80 μM) under 700 nm excitation.

[0052] Figure 16 This is a schematic diagram showing the photothermal conversion efficiency of BDB NPs under 808nm laser irradiation.

[0053] Figure 17This is a schematic diagram of the photothermal cycling results of BDB NPs and ICG under 808nm laser irradiation.

[0054] Figure 18 This is a quantitative schematic diagram illustrating the induction of apoptosis in breast cancer cells (4T1 cells) by BDB NPs (20 μM) under 808 nm laser irradiation.

[0055] Figure 19 This is a schematic diagram illustrating the biocompatibility of BDB NPs in vivo. Detailed Implementation

[0056] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and should not be construed as limiting the scope of protection of the present invention.

[0057] Example 1

[0058] BDB Synthesis Route

[0059]

[0060] Bis(4-methoxyphenyl)amine (1.15 g, 5.0 mmol) and 4,7-dibromobenzo[c][1,2,5]thiadiazole (1.18 g, 6 mmol) were added to a 100 mL Schlenk tube, followed by t-BuONa (0.86 g, 9 mmol), Pd2(dba)3 (0.27 g, 0.3 mmol), P(t-Bu)3HBF4 (0.17 g, 0.6 mmol), and redistilled toluene (30 mL). The mixture was then stirred at 110 °C for 12 hours under an argon atmosphere. The solvent was removed by rotary evaporation, and the crude product was purified three times by extraction with a mixture of dichloromethane and water, collecting the organic phase. The crude product was then purified by column chromatography on silica gel using dichloromethane / petroleum (2:1, v / v) as the eluent to give 1.1 g of red solid as compound 1, in 50% yield. 1 H NMR (400MHz, CDCl3) δ7.53 (d, J = 8.1Hz, 1H), 6.94-6.88 (m, 4H), 6.77-6.72 (m, 5H), 3.72 (s, 6H). 13 C NMR (101MHz, CDCl3) δ156.28,154.62,149.89,141.02,140.80,132.65,128.44,126. 13,126.01,120.20,120.06,114.68,114.56,105.17,55.56,55.39.HRMS(m / z):Calcd for[M+Na]+ ,464.0044;Found,464.0037.

[0061]

[0062] Compound 1 (662 mg, 1.5 mmol), Pd(Ph3P)2Cl2 (40 mg, 0.06 mmol), and 25 mL of dry toluene were added to a 100 mL pre-dried Schlenk tube, and the mixture was stirred for 30 min under an argon atmosphere. Then, a toluene solution (15 mL) of tributyl(4,4-dihexyl-4H-cyclopentano[2,1-b:3,4-b']dithiophene-2-yl)stanane (1.5 mmol) was added to the reaction mixture, and the mixture was refluxed at 120 °C for 12 h. After cooling to room temperature, the solvent was removed by rotary evaporation. The crude product was then purified by column chromatography on silica gel using dichloromethane / petroleum (1:1, v / v) as the eluent to give compound 2 (619 mg, 58% yield) as a purple solid. 1 H NMR (400MHz, CDCl3) δ7.91(s,1H),7.68(d,J=7.9Hz,1H),7.19(d,J=4.9Hz,1H),7.04-6.94(m,6H ),6.85-6.80(m,4H),3.81(s,6H),1.94-1.84(m,4H),1.21-0.97(m,16H),0.80(t,J=6.8Hz,6H). 13 C NMR (101MHz, CDCl3) δ158.90,158.34,155.96,153.46,150.83,141.33,139.81,139.01,137.05,136.76,125.82,1 25.64,125.14,122.19,114.64,114.45,55.61,55.37,53.75,37.89,31.66,29.76,24.58,22.66.HRMS(m / z):Calcd for[M+H] + ,708.2752;Found,708.2745.

[0063]

[0064] Compound 2 (707 mg, 1.0 mmol) and ultradry THF (15 mL) were added to a 50 mL Schlenk tube. The mixture was then cooled to -78 °C. n-BuLi (0.5 mL, 1.25 mmol) was added and stirring was maintained for 1 h. Then, Bu3SnCl (0.5 mL, 1.25 mmol) was added, and the mixture was heated to room temperature and stirred for 12 h. The reaction was quenched by adding an aqueous solution of NaCl. The solvent was removed under vacuum, and the crude product was purified three times by extraction with a mixture of dichloromethane and water, collecting the organic phase.

[0065] The combined organic phases were dried over anhydrous Na₂SO₄. After removing the solvent by rotary evaporation, they could be used directly without further purification.

[0066]

[0067] 3,6-bis(5-bromothiophene-2-yl)-2,5-bis(2-ethylhexyl)-2,5-dihydropyrrolo[3,4-c]pyrrolo-1,4-dione (162 mg, 0.24 mmol), Pd(Ph3P)2Cl2 (40 mg, 0.06 mmol), and 25 mL of redistilled toluene were added to a pre-dried Schlenk tube under an argon atmosphere, and the mixture was stirred at 50 °C for 30 min. Then, a toluene solution of compound 3 (15 mL, 0.75 mmol) was added to the reaction solution, and the mixture was refluxed at 120 °C for 12 h. After cooling to room temperature, the solvent was removed by rotary evaporation. The crude product was then purified by column chromatography on silica gel using dichloromethane / petroleum (2:1, v / v) as the eluent to give compound BDB as a deep blue solid (619 mg, yield 58%). NMR and mass spectrometry results are as follows. Figures 1-3 As shown, Figure 1 This is a schematic diagram of the proton NMR spectrum of compound BDB (using deuterated chloroform as the solvent). Figure 2 This is a schematic diagram of the carbon NMR spectrum of compound BDB (using deuterated chloroform as the solvent). Figure 3 This is a schematic diagram of the time-of-flight mass spectra of compound BDB. 1H NMR (400MHz, CDCl3) δ8.92(d,J=4.2Hz,2H),7.92(s,2H),7.71(d,J=7.9Hz,2H ),7.31(d,J=4.2Hz,2H),7.20(s,2H),7.01(t,J=9.3Hz,10H),6.86-6.81(m,8H ),4.09(t,J=7.8Hz,4H),3.81(s,12H),2.11-1.75(m,12H),1.42(d,J=6.8Hz,4 H),1.37-1.12(m,44H),0.92(dd,J=13.4,7.0Hz,12H),0.81(t,J=6.7Hz,12H). 13 C NMR (101MHz, CDCl3) δ156.28,154.62,149.89,141.02,140.80,132.65,128.44,126.13,126.01,120.2 0,120.06,114.68,114.56,105.17,55.56,55.39.TOF-MS(m / z):Calcd,1934.7566;Found,1934.7130.

[0068] Example 2

[0069] KDK Synthesis Route

[0070]

[0071] In a 100 mL Shrek tube, compound 1 (0.9 g, 2.04 mmol) and tetrakis(triphenylphosphine)palladium (118.35 mg, 0.1 mmol) were added, and the mixture was evacuated under argon protection. 25 mL of ultradry THF was added to a syringe. After heating to 60 °C, 2.39 mL of 4 M K₂CO₃ and 9,9-dihexylfluorene-7-bromo-2-borate pinacol ester (1.1 g, 2.04 mmol in 10 mL THF) were added, and the mixture was refluxed for 8 h. After the reaction was complete, the mixture was extracted three times with dichloromethane / saturated sodium chloride solution, and the organic phase was collected and evaporated to dryness, then dried over anhydrous magnesium sulfate. The product, compound 4, was eluted with DCM / PE (v / v = 1:1) as a deep red solid (974.32 mg, 61.8%). 1HNMR (400MHz, CDCl3) δ7.94(dd,J=7.9,1.5Hz,1H),7.87(s,1H),7.78(d,J=7.9Hz,1H),7.60(dd,J=7.8,5.8Hz,2H),7.47(dd,J=9.8,1.8Hz,2H),7.1 1-7.01(m,5H),6.87-6.81(m,4H),3.81(d,J=2.0Hz,6H),2.00(ddd,J=19. 8,13.7,9.7Hz,4H),1.11(dt,J=22.2,6.2Hz,14H),0.76(t,J=7.0Hz,8H). 13 C NMR (151MHz, CDCl3) δ155.98,153.45,141.38,140.00,139.83,136.87,129.98,128.50,128.00,127.94,126.18 ,125.82,123.50,121.14,121.04,120.72,119.73,114.54,55.47,40.25,29.68,23.78,22.58.HRMS(m / z):Calcd for[M] + ,773.2651;Found,773.2656.

[0072]

[0073] Compound 4 (695.94 mg, 0.9 mmol) and tetrakis(triphenylphosphine)palladium (52.2 mg, 0.045 mmol) were added to a 100 mL Shrek tube under argon vacuum protection. 25 mL of ultradry THF was added to a syringe. After heating to 60 °C, 2 mL of 2MK₂CO₃ and 2,5-di(2-ethylhexyl)-3,6-di(5-boronic acid pinacol ester thienyl)-pyrrolopyrroledione (232.93 g, 0.3 mmol in 10 mL THF) were added, and the mixture was refluxed for 24 h. After the reaction was complete, the mixture was extracted three times with dichloromethane / saturated sodium chloride solution, and the organic phase was collected and evaporated to dryness, then dried over anhydrous magnesium sulfate. The product KDK was eluted with PE / EA (v / v = 5:1) as a blue solid (182.3 mg, 31.8%). NMR and mass spectrometry results are as follows. Figures 4-6 As shown, Figure 4 This is a schematic diagram of the proton NMR spectrum of compound KDK (using deuterated chloroform as the solvent). Figure 5 This is a schematic diagram of the carbon NMR spectrum of compound KDK (using deuterated chloroform as the solvent). Figure 6 This is a schematic diagram of the time-of-flight mass spectrometry spectrum of compound KDK. 1H NMR (400MHz, CDCl3) δ9.03(d,J=4.1Hz,2H),7.98(dd,J=7.9,1.3Hz,2H),7.92(s,2H),7.85(d,J=7.9Hz,2H ),7.78(d,J=7.9Hz,2H),7.71(dd,J=7.9,1.6Hz,2H),7.67-7.64(m,3H),7.63(s,1H),7.56(d,J=4.1Hz,2H) ,7.11-7.03(m,10H),6.89-6.82(m,8H),4.14(h,J=7.4Hz,4H),3.82(s,12H),2.05(ddt,J=19.7,12.9,6.0 Hz,10H),1.55-1.25(m,34H),1.13(dd,J=13.5,6.9Hz,14H),0.89(d,J=7.8Hz,6H),0.76(t,J=6.8Hz,18H). 13 C NMR (151MHz, CDCl3) δ161.85,155.99,155.06,150.92,150.65,141.40,139.78,137.02,128 .54,128.01,125.85,125.33,123.57,120.75,120.46,120.27,119.98,114.55,108.22,55. 49,55.40,50.90,45.98,40.31,39.32,36.35,31.49,30.43,29.71,28.67,28.58,23.88,23 .76,23.16,22.59,14.03,10.68,8.60.TOF-MS(m / z):Calcd,1910.9309;Found,1910.9446.

[0074] Example 3

[0075] UV absorption-fluorescence emission spectra of compounds BDB and KDK in different solvents

[0076] Prepare 10 mL of 10 μM THF solution of compounds BDB and KDK respectively. Add 30 μL of each solution to 2970 μL of hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide respectively, and perform UV-Vis absorption-fluorescence emission spectroscopy measurements. Figure 7-10 As shown, Figure 7This is a schematic diagram of the normalized ultraviolet absorption spectra of compound BDB (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the absorbance. Figure 8 This is a schematic diagram of the normalized ultraviolet absorption spectra of compound KDK (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the absorbance. Figure 9 This is a schematic diagram of the normalized fluorescence emission spectra of compound BDB (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the normalized fluorescence intensity. Figure 10 This is a schematic diagram of the normalized fluorescence emission spectra of compound KDK (10 μM) in n-hexane, toluene, tetrahydrofuran, chloroform, ethanol, N,N-dimethylformamide, and dimethyl sulfoxide. The horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the normalized fluorescence intensity.

[0077] from Figure 7 and Figure 9 As can be seen, with increasing solvent polarity, the maximum absorption and maximum emission wavelengths of compound BDB gradually red-shift. From... Figure 8 and Figure 10 As can be seen, with increasing solvent polarity, the maximum absorption wavelength of compound KDK gradually redshifts, while the fluorescence emission intensity decreases sharply. In DMSO solvent, compound BDB exhibits a maximum absorption wavelength of 730 nm and a maximum emission wavelength of 903 nm, and displays strong fluorescence emission in the near-infrared II region above 1000 nm. Compound KDK in DMSO solution has a maximum absorption wavelength of 632 nm and a maximum emission wavelength of 716 nm, and shows no fluorescence emission in the near-infrared II region. These results indicate that compound BDB has a longer absorption / emission wavelength compared to compound KDK, which is beneficial for its application in near-infrared fluorescence imaging.

[0078] Example 4

[0079] Molar extinction coefficients of compounds BDB and KDK

[0080] The absorbance of compounds BDB (1.25 μM, 2.5 μM, 3.75 μM, 5 μM, 6.25 μM, 7.5 μM) and KDK (1.25 μM, 2.5 μM, 3.75 μM, 5 μM, 6.25 μM, 7.5 μM) at different concentrations in DMSO solution was measured. The molar extinction coefficients of the compounds were then calculated. The results are shown below. Figure 11 and 12 As shown, Figure 11 denoted as the molar extinction coefficient of compound BDB in DMSO solution, where: the horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the molar extinction coefficient. Figure 12 The molar extinction coefficient of compound KDK in DMSO solution is given by: the horizontal axis represents the wavelength (in nanometers), and the vertical axis represents the molar extinction coefficient. The results show that the molar extinction coefficient of compound KDK in DMSO solution is 4.4 × 10⁻⁶. 5 L mol - 1 cm -1 The level is relatively low. However, compound BDB exhibits a molar extinction coefficient as high as 1.25 × 10⁻⁶ at 730 nm. 5 L mol -1 cm -1 It is far superior to existing DAD-type pyrrolopyrrole dione small molecule dyes.

[0081] Example 5

[0082] Preparation of BDB NPs

[0083] (1) Weigh 2 mg of compound BDB and 40 mg of amphiphilic polymer DSPE-PEG. 2000 (Purchased from Xi'an Ruixi Biotechnology Co., Ltd.), dissolved in 1 mL of tetrahydrofuran solution by ultrasonication. DSPE-PEG 2000 The structure is as follows:

[0084]

[0085] (2) Under vigorous stirring, slowly add the solution prepared in (1) dropwise into a 10 mL weighing bottle containing 4 mL of deionized water and stir for 20 min.

[0086] (3) Transfer the mixture in (2) to a dialysis bag and dialyze it in a large amount of deionized water for 24 hours to obtain stable nanoparticles BDB NPs.

[0087] Example 6

[0088] Photostability testing of BDB NP nanoparticles

[0089] Add 3 mL of BDB NP nanoparticles to a fully transparent cuvette, then use 808 nm (0.8 W cm⁻¹) for chromatography. -2 The nanoparticles were irradiated with a laser for 10 minutes. The UV-Vis absorption spectra of the BDB NP nanoparticles were measured every two minutes. The absorbance of the BDB NP nanoparticles at 650 nm was plotted, and the results are shown below. Figure 13As shown. Figure 13 BDB NPs (20 μM) were subjected to continuous laser irradiation for 10 min (808 nm, 0.8 W cm⁻¹). -2 The diagram illustrates the light stability assessment, where the horizontal axis represents the illumination time (in minutes) and the vertical axis represents the absorbance. Figure 13 The results show that BDB NPs have excellent photostability and can be used for higher power (0.8W cm⁻¹) applications. -2 Photothermal therapy under 808nm laser excitation.

[0090] Example 7

[0091] In vitro near-infrared II fluorescence imaging of BDB nanoparticles

[0092] Near-infrared II (NIIR) imaging of BDB NPs nanoparticle aqueous solutions at different concentrations (0 μM, 10 μM, 20 μM, 40 μM, 80 μM) in an EP tube was performed using an InGaAs camera under 808 nm excitation and an 1100 nm long-pass filter. With increasing BDB NPs nanoparticle concentration, the solution in the EP tube exhibited gradually enhanced NIIR fluorescence, as shown in the results. Figure 14 As shown. Figure 14 In vitro near-infrared II fluorescence imaging of BDB NPs at different concentrations (0 μM, 10 μM, 20 μM, 40 μM, 80 μM) under 808 nm excitation and 1100 nm filter. Figure 14 The results show that BDB NPs have excellent near-infrared II fluorescence imaging capabilities and have the potential for imaging solid tumors.

[0093] Example 8

[0094] In vitro photoacoustic imaging of BDB nanoparticles NPs

[0095] Photoacoustic imaging of BDB NPs nanoparticle aqueous solutions at different concentrations (0 μM, 20 μM, 40 μM, 80 μM) in a capillary was performed under 700 nm excitation light using a photoacoustic imager. With increasing BDB NPs nanoparticle concentration, the solution in the capillary exhibited a gradually increasing photoacoustic signal, as shown in the results. Figure 15 As shown. Figure 15 This is a schematic diagram of in vitro photoacoustic imaging of BDB NPs at different concentrations (0 μM, 20 μM, 40 μM, 80 μM) under 700 nm excitation. Figure 15 The results show that BDB NPs have excellent photoacoustic imaging capabilities under near-infrared light excitation at 700 nm, and can be used for tumor imaging in spatial dimensions.

[0096] Example 9

[0097] Photothermal conversion efficiency and photothermal cycling tests of BDB nanoparticles

[0098] The photothermal conversion efficiency of BDB nanoparticles (40 μM) was tested in water. The test was conducted using 808 nm laser irradiation (0.8 W cm⁻¹). -2 )3 min, then cool to room temperature. The photothermal conversion efficiency (η) can be expressed by the formula η = [hs(T max -T Surr )-Q s ] / [I(1-10-A λ The result is obtained as follows: where h is the heat transfer coefficient, s is the container surface area, and Q is the heat transfer coefficient. s Let I represent the thermal change of water in this system, I be the laser power of the 808nm laser, and A be the thermal change of water. λ The absorbance of the BDB NPs nanoparticle solution at 808 nm is given. The unknown hs value is calculated using the formula hs = mC. water / τs is calculated, where m is the mass of the BDB NPs solution, and C water It is the specific heat capacity of the solution (C). water =4.2J g - 1 K -1 τs is the correlation time constant calculated based on linear time correlation data collected during the cooling period. t = -τslnθ, where θ is a dimensionless parameter called the driving force temperature. θ = (T – T) Surr ) / (T max –T Surr ), where T max and T Surr These are the highest steady-state temperature and the ambient temperature, respectively. The results are as follows: Figure 16 As shown, Figure 16 This diagram illustrates the photothermal conversion efficiency of BDB NPs under 808 nm laser irradiation. The results show that BDB NP nanoparticles in aqueous solution possess a photothermal conversion efficiency as high as 43.8%, significantly higher than that of the commercial photothermal agent indocyanine green (ICG) (<30%). Furthermore, at 808 nm (0.8 W cm⁻¹), [further details on the photothermal conversion efficiency are needed]. -2 The photothermal stability of BDB NP nanoparticles was evaluated under laser irradiation using five heat-cooling cycles. Each heating / cooling cycle lasted 3 minutes. The results are as follows: Figure 17 As shown, Figure 17This diagram illustrates the photothermal cycling results of BDB NPs and ICG under 808 nm laser irradiation. During five photothermal cycles, the BDB NP nanoparticles exhibited good photothermal stability. In contrast, the photothermal heating performance of the commercial photothermal agent ICG deteriorated with increasing cycle number. These results demonstrate the superiority of BDB NP nanoparticles as a novel photothermal formulation.

[0099] Example 10

[0100] BDB NP nanoparticles induce apoptosis in 4T1 breast cancer cells.

[0101] Take 1×10 5 4T1 cells in logarithmic growth phase were seeded in 6-well plates and incubated with BDB NP nanoparticles (20 μM) for 8 hours, followed by washing three times with PBS. The cells were then incubated using 808 nm (0.8 W cm⁻¹) nanoparticles. -2 Cells were collected 10 min after laser irradiation. They were then washed twice with pre-cooled PBS. The apoptosis rate of 4T1 cells was then detected using the Annexin V-FITC / PI apoptosis detection kit. The maximum excitation wavelength of FITC was 488 nm, and the maximum emission wavelength was 525 nm; FITC's green fluorescence was detected in the FL1 channel. The maximum excitation wavelength of the PI-DNA complex was 535 nm, and the maximum emission wavelength was 615 nm; PI's red fluorescence was detected in the FL2 or FL3 channel. A two-color scatter plot was generated using software analysis, with FITC on the x-axis and PI on the y-axis. The experimental results are shown below. Figure 18 As shown, Figure 18 This is a quantitative schematic diagram illustrating the induction of apoptosis in breast cancer cells (4T1 cells) by BDB NPs (20 μM) under 808 nm laser irradiation. The apoptosis rate of 4T1 cells treated with PBS / light / BDB NP nanoparticles alone was less than 15%, while the apoptosis rate of 4T1 cells in the experimental group treated with BDB NP nanoparticles combined with laser reached as high as 83.6%. This result indicates that BDB NP nanoparticles can effectively induce apoptosis in breast cancer cells through photothermal therapy, laying a solid foundation for photothermal therapy of solid tumors.

[0102] Example 11

[0103] Biocompatibility testing of BDB NP nanoparticles

[0104] Balb / c mice were injected with BDB NP nanoparticles (100 μM, 150 μL) via tail vein injection. Eight days after administration, the mice were sacrificed, and their major organs (heart, liver, spleen, lung, and kidney) were dissected. The biocompatibility of the BDB NP nanoparticles was assessed using H&E staining. Experimental results are as follows: Figure 19As shown, Figure 19 This is a schematic diagram illustrating the in vivo biocompatibility of BDB NPs. As can be seen from the figure, at this dosage, the BDB NP nanoparticles did not cause significant damage to the major organs of mice, demonstrating their excellent biocompatibility.

[0105] Comparative Example 1

[0106] The DAD-type pyrrolopyrrole dione derivative T14 (structure shown below) has a maximum absorption wavelength of 610 nm, a maximum emission wavelength of 665 nm, and a molar extinction coefficient of 2.3 × 10⁻⁶. 4 L mol -1 cm -1 There is no absorption at 808 nm and no fluorescence emission in the near-infrared II region above 1000 nm (Z. Yang, X. Fan, H. Li, X. Li, S. Li, Z. Zhang, H. Lin, J. Qian, and J. Hua, Chem. Eur. J., 2021, 14240-14249.).

[0107]

[0108] The D-A'-π-A-π-A'-D type pyrrolopyrroledione derivative BDB of this invention has a maximum absorption wavelength of 730 nm, a maximum emission wavelength of 903 nm, and a molar extinction coefficient of 1.25 × 10⁻⁶ in DMSO solution. 5 L mol -1 cm -1 By introducing a phenylprophiadiazole unit as an additional electron acceptor and a long-chain cyclofluorene-thiophene as a π-bridge, the absorption spectrum of the dye is redshifted from the visible light region to the near-infrared I region, and the emission spectrum is redshifted from the near-infrared I region to the near-infrared II region, with the molar extinction coefficient increased by an order of magnitude. This significantly improves the depth of in vivo fluorescence and photoacoustic imaging, while also enhancing its potential for photothermal therapy of solid tumors. More importantly, this novel molecular engineering strategy provides a series of high-performance small-molecule photothermal formulations, which to some extent accelerates the clinical translation of photothermal therapy.

[0109] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A pyrrolopyrrole dione derivative, characterized in that, It has the following general structural formula: The additional receptor is selected from one of the following structures: The π-bridge is selected from one of the following structures: m is selected from 0 to 10; n is selected from 0 to 10.

2. The pyrrolopyrrole dione derivative according to claim 1, characterized in that, In the pyrrolopyrrole dione derivative, the π-bridge is selected from one of the following structures:

3. The pyrrolopyrrole dione derivative according to claim 2, characterized in that, The pyrrolopyrrole dione derivative is selected from one of the following structures:

4. The use of a pyrrolopyrroledione derivative according to any one of claims 1 to 3 in the preparation of water-soluble nanoparticles for multimodal imaging-guided photothermal therapy.

5. The application according to claim 4, characterized in that, The application includes the following steps: The pyrrolopyrrole dione derivative and the amphiphilic polymer DSPE-PEG were mixed at a mass ratio of 1:15 to 30. 2000 The ultrasonic particles are dissolved in tetrahydrofuran solution. Under vigorous stirring, the prepared solution is slowly added dropwise to a weighing bottle containing deionized water. The mixture is stirred and dialyzed in deionized water for 1–24 hours to obtain stable nanoparticles, which are water-soluble nanoparticles used for multimodal imaging-guided photothermal therapy.

6. The use of the water-soluble nanoparticles for multimodal imaging-guided photothermal therapy as described in claim 4 or 5 in the preparation of a medicament for treating breast cancer.

7. The use of a pyrrolopyrroledione derivative according to any one of claims 1 to 3 in the preparation of a photothermal agent for multimodal imaging guidance.

Images