A triarylamine photosensitizer that generates type III "reactive oxygen species"

Abstract

The present invention provides a triarylamine photosensitizer that generates type III "reactive oxygen species". The structural formula of the triarylamine photosensitizer is shown in formula (1). Under the irradiation of a white light source, the photosensitizer can generate reactive free radicals with oxidation ability, and the generated reactive free radicals have an oxidation ability comparable to that of type I and type II ROS. Moreover, since the participation of oxygen is not required, under normoxic and hypoxic conditions, the photosensitizer can efficiently oxidize DCFH and kill tumor cells under light irradiation, which is very important for preventing tumor recurrence and treating tumors. This can well avoid the "bottleneck" of PDT relying on oxygen, improve the treatment effect, completely solve the problems of poor deep phototherapy of tumors and poor tumor suppression effect, and promote the revolutionary development in the field of PDT.

Description

Technical Field

[0001] The present invention relates to a photosensitizer, and particularly to a triarylamine photosensitizer that generates type III "reactive oxygen species". Background Art

[0002] As a non-invasive treatment method, photodynamic therapy (PDT) has been widely popularized in personalized medicine. Compared with traditional chemotherapy, radiotherapy, and surgery, PDT has the advantages of minimal invasiveness, negligible drug resistance, and controllable selection of the treatment area.

[0003] Traditional PDT involves the administration of a photosensitizer, which is excited by a visible light source and generates reactive oxygen species (ROS) in the presence of oxygen, thereby oxidatively damaging tumor cells. Type-I ROS and Type-II ROS are two well-known types of ROS. Type-I ROS mainly generate oxygen free radicals, such as superoxide radicals (O2 ·－ ) or hydroxyl radicals ( · OH), etc., through the electron transfer or energy transfer between the excited state of the photosensitizer and oxygen. Type-II ROS generate singlet oxygen ( * (T1) and triplet oxygen ( 3 O2) through the electron spin exchange between the excited state of the photosensitizer 1 O2). The generation of both type-I and type-II ROS requires the participation of oxygen. Although type-I photosensitizers can reduce their dependence on oxygen through partial oxygen cycling, oxygen is still required. However, solid tumors exist in a hypoxic environment, which greatly limits the killing effect of photosensitizing drugs on tumor cells. Moreover, the lifespan of ROS is only 1 ns, and the reaction distance between ROS and substances in cells is only 100 nm, which causes them to lose their activity before destroying cells, thereby reducing the PDT efficiency. Summary of the Invention

[0004] To solve the above technical problems, the present invention discloses a triarylamine photosensitizer that generates type III "reactive oxygen species". After being irradiated by a white light source, the photosensitizer directly oxidizes cells and induces apoptosis without the participation of oxygen.

[0005] For this, the technical solution adopted by the present invention is as follows:

[0006] A triarylamine type III "reactive oxygen species" photosensitizer, the structural formula of which is shown in formula (1):

[0007]

[0008] Wherein, R1 is

[0009] R2 is

[0010] R3 is

[0011] The photosensitizer of this technical solution is different from the traditional PDT photosensitizer. This photosensitizer does not need to rely on oxygen to produce "active oxidizing substances". The photosensitizer is composed of a triarylamine structure. It can generate corresponding triarylamine free radicals through white light source excitation. The generated free radicals have an oxidative capacity equivalent to type I and type II ROS. Since oxygen is not required, the generated free radicals can directly and efficiently oxidize DCFH (a commercial oxidative stress indicator) and kill tumor cells under normoxic and hypoxic conditions. This is very important for preventing tumor recurrence and treating tumors, and provides a guiding ideology for the development of new "ROS" photosensitizer systems.

[0012] Under the irradiation of white light source, active free radicals with oxidative ability are generated, which can be used to directly oxidize tumor cells, thereby inducing cell apoptosis.

[0013] As a further improvement of the present invention, the triarylamine photosensitizer is a compound 1-ANB having a structural formula as shown in formula (2), a compound 2-ANB having a structural formula as shown in formula (3), or a compound 9-ANB having a structural formula as shown in formula (4).

[0014]

[0015] The present invention also discloses a method for preparing the above-mentioned triarylamine Type III "active oxygen" photosensitizer, which comprises the following steps:

[0016] 1-bromoanthracene, 1-naphthylaminobenzene and sodium tert-butoxide are added to a solvent, reacted for 30 minutes under nitrogen, Pd2(dba)3 and tri-tert-butylphosphine are added, refluxed at 120° C. or reacted at 120-130° C. for more than 20 hours, cooled to room temperature, and the solvent is removed by rotary evaporation. After washing, drying and purification, 1-ANB is obtained;

[0017] Alternatively, 2-bromoanthracene, 1-naphthylaminobenzene, and sodium tert-butoxide are added to a solvent, reacted for 30 minutes under nitrogen, and then Pd2(dba)3 and tri-tert-butylphosphine are added, reacted at 120° C. for 24 hours, cooled to room temperature, and the solvent is removed by rotary evaporation. After washing, drying, and purification, 2-ANB is obtained;

[0018] Alternatively, 9-bromoanthracene, 1-naphthylaminobenzene, and sodium tert-butoxide are added to a solvent, reacted under nitrogen for 30 minutes, and then Pd2(dba)3 and tri-tert-butylphosphine are added, reacted at 120°C for 24 hours, cooled to room temperature, and the solvent is removed by rotary evaporation. After washing, drying, and purification, 9-ANB is obtained.

[0019] As a further improvement of the present invention, the solvent is o-xylene, toluene, m-xylene or p-xylene.

[0020] As a further improvement of the present invention, purification is performed by using a flash column chromatography with PE / DCM=10 / 1.

[0021] The present invention also discloses the application of the above-mentioned triarylamine Type III "active oxygen" photosensitizer for preparing drugs for treating tumors.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The photosensitizer of the technical solution of the present invention is composed of a triarylamine structure, generates active free radicals with oxidizing ability under the irradiation of a white light source, and can generate active oxides without the participation of oxygen, and has an oxidizing ability equivalent to type I and type II ROS; and because it does not require the participation of oxygen, the free radicals generated by the light-irradiated photosensitizer can efficiently oxidize DCFH and kill tumor cells under normoxic and hypoxic conditions, which is very important for preventing tumor recurrence and treating tumors. In this way, the "bottleneck" of PDT's dependence on oxygen can be well avoided, the treatment effect can be improved, the problem of poor deep tumor phototherapy and tumor inhibition effect can be completely solved, and the revolutionary development of the PDT field can be promoted. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Example 4 of the present invention was prepared in a DMSO / PBS (v / v=1 / 99) mixed solvent and irradiated with a white light source (20 mw / cm 2 ), comparison of the changes in relative fluorescence intensity (I / I0) at 525 nm of 1-ANB / 2-ANB / 9-ANB (10 μM), DCFH (5 μM), a mixture of 1-ANB / 2-ANB / 9-ANB (10 μM) and DCFH (5 μM); where a) 1-ANB, b) 2-ANB, c) 9-ANB, and L represents light.

[0025] Figure 2 The present invention Example 5 contains 1-ANB / 2-ANB / 9-ANB (50 μM) in a DMSO / PBS mixed solvent (v / v = 1 / 99) and is irradiated with a white light source (20 mw / cm 2)The decomposition rate of ABDA, where A0 is the initial absorbance of ABDA at 380 nm and A is the final absorbance of ABDA at 380 nm.

[0026] Figure 3 is the EPR spectra of 1-ANB / 2-ANB / 9-ANB (1 mM) before and after being irradiated by white light (20 mW / cm 2 ) for 30 min in the mixed solvent of THF / PBS (v / v = 1 / 9) when DMPO (100 mM) is present in Example 6 of the present invention; wherein, a) 1-ANB, b) 2-ANB, c) 9-ANB.

[0027] Figure 4 is the EPR spectra of 1-ANB / 2-ANB / 9-ANB (1 mM) before and after being irradiated by white light (20 mW / cm 2 ) for 30 min in the mixed solvent of THF / methanol (v / v = 1 / 9) when DMPO (100 mM) is present in Example 6 of the present invention; wherein, a) 1-ANB, b) 2-ANB, c) 9-ANB.

[0028] Figure 5 is the change of the relative fluorescence intensity (I / I0) at 525 nm of the mixture of 1-ANB / 2-ANB / 9-ANB (10 μM) and DCFH (5 μM) in the mixed solvents of DMSO / deoxygenated PBS and DMSO / common PBS under white light source irradiation (20 mW / cm 2 ) in Example 7 of the present invention; wherein, Hypoxia is deoxygenated PBS, Normoxia is common PBS; a) is the mixture of 1-ANB and DCFH, b) is the mixture of 2-ANB and DCFH, c) is the mixture of 9-ANB and DCFH.

[0029] Figure 6 is the change result of the relative fluorescence intensity (I / I0) at 525 nm of 1-ANB / 2-ANB / 9-ANB (10 μM), DCFH (5 μM), the mixture of 1-ANB / 2-ANB / 9-ANB (10 μM) and DCFH (5 μM) in the mixed solvent of methanol / DMSO / PBS under white light source irradiation (20 mW / cm 2 ) in Example 8 of the present invention; wherein, a) is 1-ANB, b) is 2-ANB, c) is 9-ANB.

[0030] Figure 7 is in the refined anhydrous and anaerobic toluene solution in Example 9 of the present invention, irradiated by white light for 20 min (100 mW / cm 2)EPR spectra of 1-ANB / 2-ANB / 9-ANB (10 -4 M) before and after; among them, a) is 1-ANB (10 -4 M), b) is 2-ANB (10 -4 M), c) is 9-ANB (10 -4 M).

[0031] Figure 8 is the EPR spectra of 1-ANB / 2-ANB / 9-ANB (10 -4 M) before and after being irradiated by white light (100 mw / cm -4 ) in the refined anhydrous and anaerobic toluene solution in Example 9 of the present invention when TEMPO (10 2 M) exists; among them, a) is 1-ANB (10 -4 M), b) is 2-ANB (10 -4 M), c) is 9-ANB (10 -4 M).

[0032] Figure 9 is the result of the cytotoxicity of different concentrations of 9-ANB on HepG2 under normal oxygen or hypoxic conditions with or without light source irradiation in Example 10 of the present invention, where a) is the comparison result under hypoxic conditions with or without light source irradiation, and b) is the comparison result under normal oxygen and hypoxic conditions with light source irradiation. Detailed implementation manners

[0033] The following further elaborates on the preferred embodiments of the present invention.

[0034] A triarylamine photosensitizer for generating Type III "reactive oxygen species", characterized in that its structural formula is as shown in Formula (1):

[0035]

[0036] Among them, R1 is

[0037] R2 is

[0038] R3 is

[0039] The following takes 1-ANB, 2-ANB, and 9-ANB as specific examples for introduction.

[0040] Example 1

[0041] A triarylamine Type III "reactive oxygen species" photosensitizer 1-ANB, whose structural formula is as shown in Formula (2):

[0042]

[0043] The specific synthesis route of the triarylamine compound is:

[0044]

[0045] The specific synthesis steps are as follows: o-xylene (80 mL) is added to a three-necked flask containing 1-bromoanthracene (2 g, 7.81 mmol), 1-naphthylaminobenzene (2 g, 7.81 mmol), sodium tert-butoxide (7.9 mmol, 0.8 g), and reacted for 30 min under nitrogen. o-xylene (10 mL) containing Pd2(dba)3 (2 mol%, 0.13 g) and tri-tert-butylphosphine (2 mol%, 0.026 g, 0.13 mL) is added thereto, and reacted at 120°C for 24 h. Cool to room temperature, remove o-xylene by rotary evaporation, add chloroform, wash with water, dry over anhydrous sodium sulfate, and remove all solvents by rotary evaporation. Further purification by rapid column chromatography (PE / DCM=9 / 1) gives the final product 1-ANB (1.3 g, 3.3 mmol), which is a yellow solid with a yield of 55%.

[0046] The results of the hydrogen nuclear magnetic resonance spectrum of the obtained product are: 1 H NMR (400MHz, CDCl3), δ (ppm): 8.64 (s, 1H, Ar-H), 8.45 (s, 1H, Ar-H), 8.13-8 .11(d,J=8.0Hz,1H,Ar-H),7.98-7.96(d,J=8.0Hz,1H,Ar-H),7.88-7.83(m,2 H,Ar-H),7.71-7.68(m,2H,Ar-H),7.47-7.29(m,7H,Ar-H),7.20-7.18(d,J= 8.0Hz,1H,Ar-H),7.13-7.10(t,J=4.0Hz,2H,Ar-H),6.89-6.78(m,3H,Ar-H). 13 C NMR (100MHz, CDCl3) δ (ppm) = 150.56, 145.18, 145.08, 135.35, 133.47, 131.76, 131.73, 130.45, 129.08, 129.06, 128.77, 128.59, 127. 92,127.02,126.37,126.20,126.16,125.97,125.80,125.56,125.45,125.01,124.49,124.15,123.78,120.95,120.87.HRMS(ESI)m / z calcd for C30 H 22 N[M+H] + : Theoretical value: 396.1747; actual value: 396.1764.

[0047] Example 2

[0048] A triarylamine Type III "active oxygen" photosensitizer 2-ANB, whose structural formula is as shown in formula (3):

[0049]

[0050] The specific synthesis route of the triarylamine compound is:

[0051]

[0052] The specific synthesis steps are as follows: o-xylene (80 mL) is added to a three-necked flask containing 2-bromoanthracene (3.1 g, 12 mmol), 1-naphthylaminobenzene (1.31 g, 6 mmol), sodium tert-butoxide (7.2 mmol, 0.7 g), and reacted for 30 min under nitrogen. o-xylene (10 mL) containing Pd2(dba)3 (0.5 mol%, 0.03 g) and tri-tert-butylphosphine (2 mol%, 0.0264 g, 0.12 mL) is added thereto, and reacted at 120°C for 24 h. Cool to room temperature, remove o-xylene by rotary evaporation, add chloroform, wash with water, dry over anhydrous sodium sulfate, and remove all solvents by rotary evaporation. Further purification by rapid column chromatography (PE / DCM=7 / 1) gives the final product 2-ANB (1.2 g, 3 mmol), which is a yellow solid with a yield of 50%.

[0053] The results of the hydrogen nuclear magnetic resonance spectrum of the obtained product are: 1 H NMR (400MHz, CDCl3), δ (ppm): 8.49-8.48 (d, J=4.0Hz, 1H, Ar-H), 8.24-8.19 (m, 3H, Ar-H), 8.07-8.03 (t, J=8.0Hz, 2H, Ar-H), 7 .91(s,1H,Ar-H),7.59-7.16(m,9H,Ar-H),7.06-7.03(m,2H,Ar-H),6.80-6.78(m,1H,Ar-H),6.63-6.59(t,J=8.0Hz,2H,Ar-H). 13C NMR (100MHz, CDCl3) δ (ppm) = 148.31, 145.59, 143.59, 135.45, 132.76, 132.32, 131.21, 130.81, 129.34, 129.20, 128.56, 128.29, 1 27.80,127.36,126.77,126.64,126.49,126.34,126.05,125.56,124.60,124.36,123.74,122.75,122.47,116.00.HRMS(ESI)m / z calcd for C 30 H 22 N[M+H] + : Theoretical value: 396.1747; Actual value: 396.1745.

[0054] Example 3

[0055] A triarylamine Type III "active oxygen" photosensitizer 9-ANB, whose structural formula is as shown in formula (4):

[0056]

[0057] The specific synthesis steps are as follows: o-xylene (80 mL) is added to a three-necked flask containing 9-bromoanthracene (3.1 g, 12 mmol), 1-naphthylaminobenzene (1.31 g, 6 mmol), sodium tert-butoxide (7.2 mmol, 0.7 g), and reacted for 30 min under nitrogen. o-xylene (10 mL) containing Pd2(dba)3 (2 mol%, 0.12 g) and tri-tert-butylphosphine (2 mol%, 0.0264 g, 0.12 mL) is added thereto, and reacted at 120°C for 24 h. Cool to room temperature, remove o-xylene by rotary evaporation, add chloroform, wash with water, dry over anhydrous sodium sulfate, and remove all solvents by rotary evaporation. Further purification by rapid column chromatography (PE / DCM=10 / 1) gives the final product 9-ANB (0.8 g, 2 mmol), which is a yellow solid with a yield of 34%.

[0058] The results of the hydrogen nuclear magnetic resonance spectrum of the obtained product are: 11H NMR (400 MHz, CDCl3), δ (ppm): δ 8.48 (s, 1H, Ar-H), 8.24 - 8.20 (t, J = 8.0 Hz, 3H, Ar-H), 8.05 - 8.03 (d, J = 8.0 Hz, 2H, Ar-H), 7.91 - 7.89 (d, J = 8.0 Hz, 2H, Ar-H), 7.59 - 7.57 (d, J = 8.0 Hz, 1H, Ar-H), 7.40 - 7.31 (m, 6H, Ar-H), 7.27 - 7.23 (m, 2H, Ar-H), 7.14 - 7.12 (d, J = 8.0 Hz, 2H, Ar-H), 7.53 - 7.39 (m, 4H, Ar-H), 7.31 - 7.27 (t, J = 8.0 Hz, 2H, Ar-H), 7.18 - 7.14 (t, J = 8.0 Hz, 1H, Ar-H), 7.06 - 7.03 (m, 3H, Ar-H) 6.80 - 6.76 (t, J = 8.0 Hz, 1H, Ar-H), 6.61 - 6.59 (d, J = 8.0 Hz, 2H, Ar-H). 13 13C NMR (100 MHz, CDCl3) δ (ppm) = 150.72, 142.84, 139.68, 135.35, 132.89, 130.94, 129.17, 129.13, 128.99, 128.31, 126.74, 126.69, 126.25, 125.86, 125.82, 125.65, 125.49, 125.16, 124.66, 123.00, 119.87, 118.54. HRMS (ESI) m / z calcd for C 30 H 22 N [M + H] + : Theoretical value: 396.1747; Measured value: 396.1749.

[0059] Example 4

[0060] Next, the photodynamic properties of compounds 1-ANB, 2-ANB, and 9-ANB in Examples 1 to 3 were analyzed. Using 2,7-dichlorodihydrofluorescein (DCFH, a commercial oxidative stress indicator) as an index, the ability to generate "reactive oxygen species" under white light irradiation was evaluated.

[0061] 1-ANB, 2-ANB, 9-ANB, and DCFH were respectively added to a DMSO / PBS (v / v = 1 / 99) mixed solvent and irradiated with a white light source (20 mw / cm 2)Under the following conditions, the changes in the relative fluorescence intensity (I / I0) at 525 nm of 10 μM 1-ANB / 2-ANB / 9-ANB, 5 μM DCFH, and the mixture of 10 μM 1-ANB / 2-ANB / 9-ANB (10 μM) and 5 μM DCFH are as Figure 1 shown. It can be seen that after exposure to white light for 5 min, the fluorescence intensities of the mixture of 1-ANB / 2-ANB / 9-ANB (10 μM) and 5 μM DCFH at 525 nm increased by 124, 151, and 170 times respectively, indicating the efficient generation of "reactive oxygen species". In the absence of the compound 1-ANB / 2-ANB / 9-ANB, for 5 μM DCFH or without light source irradiation, the fluorescence intensity at 525 nm hardly changed, indicating that the generation of "reactive oxygen species" requires the simultaneous presence of 1-ANB / 2-ANB / 9-ANB and light irradiation.

[0062] Example 5

[0063] Using 9,10-anthracenediyl-bis(methylene)-di-dioic acid (ABDA, a commercial 1 O2 indicator) as an indicator to detect whether Type II ROS ( 1 O2) is generated during light irradiation. Specifically:

[0064] 1-ANB, 2-ANB, and 9-ANB were added to a DMSO / PBS mixed solvent (v / v = 1 / 99) at a concentration of 50 μM each, and the indicator ABDA was added. Then, under white light source irradiation (20 mw / cm 2 ), the decomposition rate of ABDA was detected. The results are as Figure 2 shown, Figure 2 where A0 is the initial absorbance of ABDA at 380 nm and A is the final absorbance of ABDA at 380 nm. The results show that when the solution containing 1-ANB / 2-ANB / 9-ANB and ABDA was irradiated for 5 minutes under light, the absorbance of ABDA hardly changed, indicating that no Type II ROS ( 1 O2) was generated.

[0065] Example 6

[0066] In this example, electron paramagnetic resonance (EPR) spectroscopy was used, and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO, a commercial O2 ·－ and · OH radical scavenger) was used as a spin trap for Type I ROS (O2 ·－ , ·OH) to confirm whether O2 ·－ and · OH were generated during light irradiation. Specifically:

[0067] In a mixed solvent of THF / PBS (v / v = 1 / 9), when DMPO (100 mM) is present, the EPR spectra of 1-ANB, 2-ANB, and 9-ANB (1 mM) before and after being irradiated by white light (20 mw / cm 2 ) for 30 min were detected, and the results are as Figure 3 shown. In a mixed solvent of THF / methanol (v / v = 1 / 9), when DMPO (100 mM) is present, the EPR spectra of 1-ANB, 2-ANB, and 9-ANB (1 mM) before and after being irradiated by white light (20 mw / cm 2 ) for 30 min were detected, and the results are as Figure 4 shown. As can be seen from Figure 3 and Figure 4 , when a solution containing 1-ANB / 2-ANB / 9-ANB and DMPO is irradiated with a white light source, the characteristic ESR signals of O2 ·－ and · OH are not captured, indicating that during the irradiation process, neither O2 ·－ nor · OH is generated.

[0068] According to the above test results, it can be seen that the "active oxides" generated by irradiating 1-ANB / 2-ANB / 9-ANB are not the commonly mentioned type I and type II ROS. That is, 1-ANB / 2-ANB / 9-ANB can generate "active oxides" with oxidation ability equivalent to that of type I and type II ROS under light irradiation without the participation of oxygen. To verify this conjecture, deoxygenated PBS and ordinary PBS were used as solvents respectively, and DCFH was used as an index to evaluate the generation ability of "active oxides" under hypoxic and normoxic conditions under white light irradiation.

[0069] Example 7

[0070] On the basis of Example 6, in this example, normal PBS and deoxygenated PBS were used as solvents respectively, and the oxidation effect of 1-ANB, 2-ANB, and 9-ANB (10 μM) on DCFH (5 μM) during white light (20 mw / cm 2 ) irradiation was detected. The results are as Figure 5 shown. It can be seen that whether in deoxygenated PBS or ordinary PBS solution, during the 5-min irradiation with a white light source, the degree of increase in fluorescence intensity at 525 nm is almost the same, that is, the generation ability of "active oxides" is almost the same. This shows that the process of generating "active oxides" by irradiating 1-ANB / 2-ANB / 9-ANB does not require the participation of oxygen.

[0071] Considering that the oxygen content in the aqueous solution is low and it is difficult to remove it completely, it was decided to replace PBS with methanol and re-evaluate the ability to generate "active oxides" under hypoxic and normoxic conditions under white light irradiation (at 25 °C and 101.325 KPa, the solubility of oxygen in water is 2.831 mL / 100 mL; the solubility of oxygen in methanol is 24.76 mL / 100 mL). See Example 8 for details. Example 8

[0072] 1-ANB, 2-ANB, and 9-ANB were added to 3 portions of methanol / DMSO / PBS mixed solvents (where methanol: 1980 μL; DMSO: 4 μL; PBS: 20 μL) such that the concentrations of 1-ANB, 2-ANB, and 9-ANB were 10 μM; and DCFH was added to one portion of methanol / DMSO / PBS mixed solvent (where methanol: 1980 μL; DMSO: 4 μL; PBS: 20 μL) such that the concentration of DCFH was 5 μM; in another three portions of methanol / DMSO / PBS mixed solvents (where methanol: 1980 μL; DMSO: 4 μL; PBS: 20 μL), mixtures of DCFH and 1-ANB, DCFH and 2-ANB, and DCFH and 9-ANB were added such that the concentration of DCFH in each portion was 5 μM, and the concentrations of 1-ANB, 2-ANB, and 9-ANB were 10 μM. Then the above samples were irradiated under a white light source (20 mw / cm 2 ) to obtain the change in the relative fluorescence intensity (I / I0) at 525 nm, and a deoxygenated methanol solution containing a mixture of DCFH and 1-ANB, DCFH and 2-ANB, and DCFH and 9-ANB was used as a control. The results are as Figure 6 shown.

[0073] It can be seen that, relative to DCFH, in a deoxygenated methanol solution, after 5 min of white light irradiation, the fluorescence intensities at 525 nm of 1-ANB, 2-ANB, and 9-ANB increased by 192, 190, and 483 times respectively, indicating the efficient generation of "active oxides". While in ordinary methanol, the fluorescence intensities at 525 nm only increased by 36, 75, and 18 times. This further shows that the generation of "active oxides" by irradiating 1-ANB / 2-ANB / 9-ANB does not require the participation of oxygen. Moreover, when the oxygen concentration is relatively high, it will quench the generated oxides and reduce the oxidation effect on DCFH (at 25 °C and 101.325 KPa, the solubility of oxygen in water is 2.831 mL / 100 mL; the solubility of oxygen in methanol is 24.76 mL / 100 mL).

[0074] Example 9

[0075] 1-ANB, 2-ANB, and 9-ANB were separately dissolved in refined anhydrous and anaerobic toluene. Under the excitation of a white light source, EPR was used to detect whether free radicals were generated every 2 min. The results are as Figure 7 shown. It can be seen that no signal of free radicals was detected until 20 min after the light source excitation. This may be because the generated free radicals have a short lifespan and cannot be captured by EPR.

[0076] In addition, 2,2,6,6-tetramethylpiperidine oxide (TEMPO, a commercial free radical scavenger) was used as a spin scavenger. TEMPO was added to the anhydrous and anaerobic toluene solutions of 1-ANB, 2-ANB, and 9-ANB respectively. Under light irradiation, EPR was used to detect whether free radicals were generated. The results are as Figure 8 shown. It can be seen that the free radicals generated by 1-ANB, 2-ANB, and 9-ANB in refined anhydrous and anaerobic toluene were captured. This result proves that in the solution state, the three compounds generated free radicals under white light source irradiation. The free radicals generated by light irradiation are similar to O2 ·－ and · OH. Due to the incomplete valence saturation and high energy of themselves, they are unstable and have a short lifespan, and it is difficult to be directly detected by EPR. However, due to their high energy, the free radicals generated by 1-ANB / 2-ANB / 9-ANB after light irradiation can directly oxidize DCFH without the participation of oxygen, showing the same oxidation performance as type I and type II ROS. Aniline is prone to generate free radicals under light irradiation, and the "active oxides" generated by 1-ANB / 2-ANB / 9-ANB after light irradiation are the corresponding aniline cation free radicals.

[0077] Based on the above results, the free radicals generated by the compounds shown in formula (1) (including 1-ANB / 2-ANB / 9-ANB, etc.) after light irradiation are called type III "reactive oxygen species (ROS)", and the compounds shown in formula (1) (including 1-ANB / 2-ANB / 9-ANB, etc.) are called type III "reactive oxygen species (ROS)" photosensitizers.

[0078] Example 10

[0079] In this example, MTT assay was used to evaluate the PDT effect of 9-ANB on HepG2 cells. Under normoxia and hypoxia conditions respectively, the HepG2 cell solution containing different concentrations of 9-ANB was irradiated with white light (20 mW / cm 2 ) for 30 min, and the condition without a light source was used as a control. The cytotoxicity results of HepG2 containing different concentrations of 9-ANB are as Figure 9 shown. It can be seen that the compound 9-ANB shows obvious cytotoxicity to HepG2 cells, and the half maximal inhibitory concentration (IC50 ) was 0.94 μM. More importantly, compound 9-ANB also exhibited good anti-tumor effects under hypoxic conditions (IC 50 = 1.01 μM). Without light irradiation, 9-ANB was not toxic to HepG2 cells under both normoxic and hypoxic conditions.

[0080] As can be seen from the above examples, the triarylamine radicals generated by irradiating compounds such as 1-ANB / 2-ANB / 9-ANB have an oxidation ability comparable to that of type I and type II ROS. Since the participation of oxygen is not required, the radicals generated by irradiating compounds such as 1-ANB / 2-ANB / 9-ANB can efficiently oxidize DCFH and kill tumor cells under both normoxic and hypoxic conditions. This is very important for preventing tumor recurrence and treating tumors, and there are extensive potential applications in the fields of photocatalysis, biomaterials, physical chemistry, and medicinal chemistry.

[0081] Furthermore, by analyzing the structures of 1-ANB / 2-ANB / 9-ANB compounds, it was found that due to the p-π conjugation of the lone pair electrons on the nitrogen atom with the three connected benzene rings in the triarylamine molecule, the triarylamine has a very low ionization potential and is very easy to form radicals under the conditions of light irradiation, oxidants, and electrolysis. The spin density of the triarylamine radical will be delocalized and can form resonance forms, and the spin density is mainly distributed at the ortho and para positions of the nitrogen and benzene rings. This makes the triarylamine radical have a certain stability and relatively high reactivity, and is prone to reactions such as oxidation, hydrogen abstraction, and disproportionation. By modifying the triarylamine molecule, an oxidized radical with better stability can be obtained, and then a new type of commercial radical oxidant can be developed. Common modification strategies include: introducing bulky groups to synthesize planar triarylamines with spin density delocalized throughout the molecule; introducing protecting groups at the para position of the benzene ring; introducing heteroatoms such as S, O, and N to reduce the spin density on the benzene ring in the triarylamine. Therefore, it can be seen that compounds with the structural formula shown in formula (1) can all achieve this function.

[0082] The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. Application of a triarylamine Type Ⅲ "reactive oxygen species" photosensitizer, characterized in that: For preparing a drug for treating tumors; the triarylamine Type III "active oxygen" photosensitizer is a compound 1-ANB with a structural formula as shown in formula (2), a compound 2-ANB with a structural formula as shown in formula (3), or a compound 9-ANB with a structural formula as shown in formula (4); 2. Use of the triarylamine Type III "reactive oxygen species" photosensitizer according to claim 1, characterized in that, The preparation method of the triarylamine Type III "active oxygen" photosensitizer comprises the following steps: 1-bromoanthracene, 1-naphthylaminobenzene and sodium tert-butoxide are added to a solvent, reacted for 30 minutes under nitrogen, Pd2(dba)3 and tri-tert-butylphosphine are added, refluxed at 120° C. or reacted at 120-130° C. for more than 20 hours, cooled to room temperature, and the solvent is removed by rotary evaporation. After washing, drying and purification, 1-ANB is obtained; Alternatively, 2-bromoanthracene, 1-naphthylaminobenzene, and sodium tert-butoxide are added to a solvent, reacted for 30 minutes under nitrogen, and then Pd2(dba)3 and tri-tert-butylphosphine are added, reacted at 120° C. for 24 hours, cooled to room temperature, and the solvent is removed by rotary evaporation. After washing, drying, and purification, 2-ANB is obtained; Alternatively, 9-bromoanthracene, 1-naphthylaminobenzene, and sodium tert-butoxide are added to a solvent, reacted under nitrogen for 30 minutes, and then Pd2(dba)3 and tri-tert-butylphosphine are added, reacted at 120°C for 24 hours, cooled to room temperature, and the solvent is removed by rotary evaporation. After washing, drying, and purification, 9-ANB is obtained.

3. Use of the triarylamine Type III "reactive oxygen species" photosensitizer according to claim 2, characterized in that: The solvent is o-xylene, toluene, m-xylene or p-xylene.

4. The use of the triarylamine Type III "active oxygen" photosensitizer according to claim 2, characterized in that: Purification was carried out by flash column chromatography with PE / DCM=10 / 1.

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