Ionic iridium (III) complex based on (+ 3, + 2, + 1)-[Ir (NCN / NNN) (CN) (R)] + / 2 + configuration and preparation

Abstract

The invention relates to an ionic iridium (III) complex based on (+ 3, + 2, + 1)-[Ir (NCN / NNN) (CN) (R)] < + / 2 + > configuration and a preparation method and application thereof, and the preparation method comprises the following steps: 1, reacting a tridentate ligand NCN / NNN with iridium chloride trihydrate in a specific solvent to obtain a first intermediate; 2, reacting the obtained first intermediate with a bidentate ligand HCN to obtain a second intermediate; and step 3, substituting the second intermediate with a monodentate cyanide ligand R to obtain a target product. The complex is efficient in synthesis method, has good photophysical properties, and has low cytotoxicity and high phototoxicity index for lung cancer cells, colon cancer cells and liver cancer cells, which shows that the complex has good application prospects in the field of metal anti-cancer drugs.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of medicine, and particularly relates to an ionic iridium (III) complex based on (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R) + / 2+ configuration and a preparation method and application thereof. BACKGROUND

[0002] Photoactivated chemotherapy (PACT) can significantly reduce the systemic toxicity of traditional chemotherapy due to its spatiotemporal controllability, and is an important research direction of precision medicine. Among numerous photoactivators, iridium (III) complexes exhibit unique advantages and have become a research hotspot in recent years. Compared with other metal complexes, iridium (III) complexes have excellent photo-physical properties: excellent light stability, high triplet excited state quantum yield, and long excited state lifetime, which enables them to efficiently generate cytotoxic singlet oxygen (1O2) through type II mechanism or reactive oxygen species (ROS) through type I mechanism, effectively inducing cancer cell apoptosis. In addition, their luminescence characteristics can be used for cell imaging, realizing integrated diagnosis and treatment. Current research focuses on designing new cyclometallated iridium (III) complexes, and modifying auxiliary ligands (such as N^N ligands) or main ligands to regulate their excitation wavelength, ROS production efficiency, and cell uptake capacity, in order to achieve excitation by visible light or even near-infrared light with stronger penetration.

[0003] However, the existing iridium-based PACT reagents still face severe challenges. The first problem is that the excitation wavelength is mostly in the ultraviolet or blue-green light region, with weak tissue penetration ability, which seriously limits its application in the treatment of deep solid tumors. Secondly, the dark toxicity of many complexes is still relatively high, and the phototoxicity index (PI) is insufficient, which poses potential systemic safety risks. In addition, there is a lack of active targeting to the tumor microenvironment, resulting in less than ideal selective enrichment. Therefore, there is an urgent need in the art to develop a new type of iridium (III) complex with red-shifted absorption spectrum, which can be effectively activated by longer wavelength (such as >600 nm) light, while having extremely low dark toxicity and higher phototoxicity index, to solve the key bottleneck in the prior art. SUMMARY

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present application is to provide an ionic iridium (III) complex based on (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R) + / 2+ configuration and a preparation method and application thereof, which improves the performance of the iridium (III) complex by modifying the molecular structure of the tridentate ligand, bidentate ligand, and monodentate ligand, so that the material has lower dark toxicity and higher phototoxicity index.

[0005] In order to achieve the above object, the technical scheme adopted by the present application is:

[0006] An ionic iridium (III) complex based on (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configuration, characterized in that, taking the metal-iridium as the light-emitting center, a tridentate ligand (N^C^N or N^N^N), a bidentate ligand (HC^N) and a monodentate cyanide ligand (R) are chelated with iridium metal to form, the general structure is as shown in formula 1:

[0007]

[0008] Among them, the ionic iridium (III) complex of (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configuration, the tridentate ligand (N^C^N or N^N^N) is various aromatic compounds with strong coordination ability and easy to introduce targeting groups for functionalization, among which the most representative is the structure containing terpyridine, which can be selected from one of the following structures.

[0009]

[0010] Among them, the bidentate ligand (HC^N) selects the pyridine-thiophene structure with rich electrons, which is beneficial to improve the energy level of the highest occupied orbital (HOMO), thereby reducing the energy gap (E g ), so as to make the emission wavelength red shift, which can be selected from one of the following structures:

[0011]

[0012] Among them, the monodentate ligand selects the isocyanide compound, and the advantage of the aryl isocyanide ligand lies in the perfect combination of its "adjustable strong electron-donating property" and "moderate electron-accepting property", and it can be realized through the large space adjustability. It can be selected from one of the following structures:

[0013] An ionic iridium (III) complex based on (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configuration, characterized in that, the synthesis route is as follows:

[0014]

[0015] An ionic iridium (III) complex based on (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configuration, characterized in that, the preparation method comprises the following steps:

[0016] Step 1, preparation of bridged intermediate {[Ir(N^C^N)Cl(μ - Cl)]2}: in a mixed solvent of ethylene glycol monoethyl ether and deionized water, a mixture of tridentate ligand (N^C^N) and iridium chloride trihydrate is added, and placed under the condition of inert gas nitrogen, and the bridged intermediate {[Ir(N^C^N)Cl(μ-Cl)]2} is obtained at 110°C;

[0017] Step 2, preparation of neutral iridium (III) complex of [Ir(N^C^N)(C^N)(Cl)] type: in a toluene system, in the presence of silver trifluoromethanesulfonate, the bridged intermediate and the bidentate ligand (HC^N) are placed under the condition of inert gas nitrogen, and the neutral iridium (III) complex of [Ir(N^C^N)(C^N)(Cl)] type is obtained by reaction at 110°C;

[0018] Step 3, preparation of ionic iridium (III) complex of [Ir(N^C^N)(C^N)(R)] + type: in a methanol system, in the presence of silver trifluoromethanesulfonate, the neutral iridium (III) complex of [Ir(N^C^N)(C^N)(Cl)] type purified by silica gel column in the previous step is placed under the condition of inert gas nitrogen, and the ionic iridium (III) complex of [Ir(N^C^N)(C^N)(R)] + type is obtained by reaction at 65°C in the dark.

[0019] The molar ratio of the tridentate ligand (N^C^N) and iridium chloride trihydrate in step 1 is 1.1:1.

[0020] The molar ratio of the bridged intermediate and the bidentate ligand (HC^N) in step 2 is 1:2.5.

[0021] The molar ratio of the neutral iridium (III) complex of [Ir(N^C^N)(C^N)(Cl)] type and the monodentate cyanogen ligand R in step 3 is 1:2.5.

[0022] A method for preparing an ionic iridium (III) complex of (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R) + / 2+ type, characterized in that it comprises the following steps:

[0023] Step 1, preparation of intermediate {[Ir(N^N^N)Cl3]}: in ethylene glycol, a mixture of tridentate ligand (N^N^N) and iridium chloride trihydrate is added, and placed under the condition of inert gas nitrogen, and the intermediate {[Ir(N^N^N)Cl3]} is obtained by reaction in the dark at 160°C.

[0024] Step 2, preparation of [Ir(N^N^N)(C^N)(Cl)] + type ionic iridium (III) complex: in ethylene glycol, the intermediate {[Ir(N^N^N)Cl3]} and the bidentate ligand (HC^N) are placed under the condition of inert gas nitrogen at 180℃ in the dark to obtain the [Ir(N^C^N)(C^N)(Cl)] type neutral iridium (III) complex.

[0025] Step 3, preparation of [Ir(N^N^N)(C^N)(R)] 2+ type ionic iridium (III) complex: in a methanol system, in the presence of silver trifluoromethanesulfonate, the [Ir(N^N^N)(C^N)(Cl)] purified by silica gel column in the previous step is placed under the condition of inert gas nitrogen at 65℃ in the dark to obtain the [Ir(N^N^N)(C^N)(R)] type ionic iridium (III) complex. + type ionic iridium (III) complex and the monodentate cyanogen ligand R are placed under the condition of inert gas nitrogen at 65℃ in the dark to obtain the [Ir(N^N^N)(C^N)(R)] type ionic iridium (III) complex. 2+ type ionic iridium (III) complex.

[0026] The molar ratio of the tridentate ligand (N^N^N) and iridium chloride trihydrate in step 1 is 1.1:1.

[0027] The molar ratio of the intermediate and the bidentate ligand (HC^N) in step 2 is 1:1.1.

[0028] The molar ratio of the [Ir(N^N^N)(C^N)(Cl)] in step 3 and the monodentate cyanogen ligand R is 1:2.5. + type ionic iridium (III) complex and the monodentate cyanogen ligand R are placed under the condition of inert gas nitrogen at 65℃ in the dark to obtain the [Ir(N^N^N)(C^N)(R)] type ionic iridium (III) complex.

[0029] A (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] type ionic iridium (III) complex based on + / 2+ Application of the (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] type ionic iridium (III) complex in anti-tumor, the anti-tumor activity of cells is tested by the traditional MTT colorimetric method to test the inhibition effect of tumor cells such as lung cancer cells, colon cancer cells and liver cancer cells.

[0030] The effective effects of the present application:

[0031] The (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] type ionic iridium (III) complex provided by the present application has the advantages of: + / 2+The method for preparing ionic iridium(III) complexes with the specified configuration is simple and efficient, and the prepared iridium(III) complexes exhibit good photostability. Furthermore, the iridium(III) complexes provided by this invention possess excellent antitumor properties, exhibiting low dark toxicity and high phototoxicity against lung cancer, colon cancer, and liver cancer cells, indicating significant potential for application in photoactivated therapy (PACT). Attached Figure Description

[0032] Figure 1 For neutral iridium(III) complexes of the [Ir(N^C^N)(C^N)(Cl)] type ([Ir(dpyb)(iqbt)(Cl)]) 1 HNMR spectrum;

[0033] Figure 2 =[Ir(N^C^N)(C^N)(R)] + Type Ionic Iridium(III) Complex (1a) 1 HNMR spectrum;

[0034] Figure 3 [Ir(N^N^N)(C^N)(Cl)] + Type Ionic Iridium(III) Complex ([Ir(tpy)(iqbt)(Cl)]) + )of 1 HNMR spectrum;

[0035] Figure 4 =[Ir(N^N^N)(C^N)(R)] 2+ Type ionic iridium(III) complex (1b) 1 HNMR spectrum;

[0036] Figure 5 =[Ir(N^C^N)(C^N)(R)] + Crystal structure diagram of the ionic iridium(III) complex (1a);

[0037] Figure 6 =[Ir(N^N^N)(C^N)(R)] 2+ Crystal structure diagram of the ionic iridium(III) complex (1b);

[0038] Figure 7 =[Ir(N^C^N)(C^N)(R)] + Type Ionic Iridium(III) Complexes (1a), [Ir(N^N^N)(C^N)(R)] 2+ Absorption spectrum of the ionic iridium(III) complex (1b) in dichloromethane;

[0039] Figure 8 [Ir(N^C^N)(C^N)(R)] + [Ir(N^N^N)(C^N)(R)] 2+ [Ir(N^N^N)(C^N)(R)] DETAILED DESCRIPTION

[0040] The technical solutions of the present application will be further illustrated by specific examples below, so as to more fully understand the content of the present application.

[0041] Example 1: The present example provides a method for preparing an ionic iridium (III) complex (1a) of the formula: + [Ir(N^N^N)(C^N)(R)] 2+ [Ir(N^N^N)(C^N)(R)]

[0042]

[0043] [Ir(N^C^N)(C^N)(R)] + The preparation method of the ionic iridium (III) complex (1a) of the formula:

[0044] Step 1, synthesis of bridged intermediate {[Ir(dpyb)Cl(μ-Cl)]2}: in a mixed solvent of ethylene glycol monoethyl ether and deionized water (v / v = 3:1), add iridium chloride trihydrate and tridentate ligand 1,3-bis(pyridin-2-yl)benzene dpyb in a molar ratio of 1:1.1. Then react at 110°C for 48 hours under the condition of inert gas nitrogen. After the reaction is completed, it is cooled to room temperature, saturated brine is added to the mixed solution, orange precipitate is precipitated, the filter cake is filtered and washed with deionized water, and is placed in a vacuum drying oven at 45°C for drying, to obtain a red mixture powder containing the bridged intermediate {[Ir(dpyb)Cl(μ-Cl)]2}, which is directly used for the next step experiment without further treatment.

[0045] Step 2, synthesis of [Ir(dpyb)(iqbt)(Cl)] : Weighed { [Ir(dpyb)Cl(μ-Cl)]2} and bidentate ligand 1-(benzo[b]thiophen-2-yl)-isoquinoline Hiqbt (molar ratio = 1 :2.5) into a pressure tube, and added excess silver trifluoromethanesulfonate. Repeatedly vacuumed and filled with nitrogen gas three times with the bottle cap half-tightened, and added toluene when filling with nitrogen gas for the last time, then tightened the bottle cap. The pressure tube containing the reactants was placed in an oil bath pot at 110°C for 48 hours of reaction. After the reaction was completed, extraction was performed with dichloromethane, followed by purification through a silica gel column (v / v, DCM:PE = 4:1), to obtain an orange powder. We performed a nuclear magnetic resonance hydrogen spectrum test on it, as shown in Figure 1 , and the results were as follows: 1 HNMR (400MHz, CDC13) δ 10.14 (d, 1H), 9.19 (d, 1H), 8.03 (d, 1H), 7.88 (d, 2H), 7.81 (m, 4H), 7.72 (d, 1H), 7.61 (d, 1H), 7.52 (m, J = 6.1 Hz, 4H), 7.42 (t, 1H), 7.05 (t, 1H), 6.75 (q, 3H), 6.36 (d, 1H).

[0046] Step 3, synthesis of [Ir(dpyb)(iqbt)(CNAr dmp )] + (1a) : In a methanol solution, we added [Ir(dpyb)(iqbt)(Cl)] obtained in Step 2 and monodentate cyano ligand 2,6-dimethylphenyl isocyanide CNAr dmp (molar ratio = 1 :2.5). Under the condition of inert gas nitrogen, we reacted at 65°C for 24 hours in the dark. After the reaction was completed, we performed filtration and concentration, and separated and purified [Ir(dpyb)(iqbt)(CNAr dmp )] + (1a) through a silica gel column, using a mixture of dichloromethane and acetonitrile (v / v = 40:1-20:1) as the eluent. We performed a nuclear magnetic resonance hydrogen spectrum test on it, as shown in Figure 4 , and the analysis results were as follows: 1HNMR (400 MHz, CDC13) δ 9.38 (d, J = 6.1 Hz, 1H), 9.24 (d, J = 8.2 Hz, 1H), 8.19 - 8.14 (m, 1H), 7.98 (dd, J = 9.2, 7.1 Hz, 5H), 7.95 - 7.86 (m, 2H), 7.83 - 7.75 (m, 4H), 7.71 - 7.61 (m, 2H), 7.12 - 7.06 (m, 2H), 7.05 - 6.96 (m, 4H), 6.75 (t, J = 7.7 Hz, 1H), 5.97 (d, J = 8.2 Hz, 1H), 1.94 (s, 6H, -CH3).

[0047] [Ir(N^N^N)(C^N)(R)] 2+ The method for preparing the ionic iridium (III) complex (1b) of Formula I is as follows:

[0048] Step 1, synthesis of intermediate {[Ir(tpy)(Cl3)]}: in ethylene glycol solvent, add iridium chloride trihydrate and tridentate ligand 2,2':6',2"-terpyridine tpy in a molar ratio of 1:1.1. Then react under the condition of inert gas nitrogen at 160°C for 30 minutes in the dark. After the reaction is completed, it is lowered to room temperature, deionized water is added to the mixed solution, a red precipitate is precipitated, the filter cake is filtered and washed with deionized water, and then dried in a vacuum drying oven at 45°C to obtain red {[Ir(tpy)(Cl3)]}, which is directly used for the next step experiment without further treatment.

[0049] Step 2, synthesis of [Ir(tpy)(iqbt)(Cl)]: + In a pressure tube, weigh {[Ir(tpy)(Cl3)]} and bidentate ligand 1-(benzo[b]thiophen-2-yl)-isoquinoline Hiqbt (molar ratio = 1:1.1), and add excess silver trifluoromethanesulfonate. Repeat vacuum and nitrogen three times with the bottle plug half-tightened, and then add ethylene glycol during the last time of nitrogen filling, and then tighten the bottle plug. Place the pressure tube containing the reactants in an oil bath at 180°C for 24 hours. After the reaction is completed, add deionized water to precipitate an orange-red precipitate, filter and wash the filter cake with deionized water, and then purify by silica gel column chromatography (v / v, DCM:AC = 6:1) to obtain an orange-red powder. Perform nuclear magnetic resonance hydrogen spectrum test on it, as shown in Figure 3 the results are as follows: 1HNMR(400MHz,DMSO-d6)δ9.90(d,J=6.6Hz,1H),9.04(dd,J=13.7,8.9Hz,3H),8.79(d,J=8.1Hz ,2H),8.73(t,J=8.1Hz,1H),8.38–8.31(m,1H),8.18(td,J=7.9,1.5Hz,2H),8.12(d,J=6.6Hz,1 H),8.09–8.02(m,2H),7.94(d,J=8.0Hz,1H),7.80–7.72(m,2H),7.48(ddd,J=7.4,5.6,1.4Hz,2 H),7.26(ddd,J=8.1,7.1,1.1Hz,1H),6.97(ddd,J=8.2,7.1,1.1Hz,1H),5.99(d,J=8.0Hz,1H).

[0050] Step 3, [Ir(tpy)(iqbt)(CNAr dmp )] 2+ Synthesis of (1b): [Ir(tpy)(iqbt)(Cl)] obtained in step 2 was added to a methanol solution. + Monodentate cyanide ligand 2,6-dimethylphenylisocyanide CNAr dmp (Molar ratio = 1:2.5). The reaction was carried out at 65°C in the dark for 24 hours under inert nitrogen atmosphere. After the reaction was complete, the mixture was filtered and concentrated. The purified product was obtained by silica gel column chromatography using a mixed solvent of dichloromethane and acetone (v / v = 20:1-10:1) as the eluent, yielding [Ir(tpy)(iqbt)(CNAr]. dmp )] 2+ (1b). Perform proton nuclear magnetic resonance spectroscopy on it, such as... Figure 4 As shown, the analysis results are as follows: 1HNMR (400 MHz, DMSO-d6) δ 9.50 (d, J = 6.7 Hz, 1H), 9.19 (d, J = 8.4 Hz, 2H), 9.10 (m, 1H), 8.97 (d, J = 8.1 Hz, 1H), 8.93 (m, 2H), 8.42 (m, 1H), 8.34 (td, J = 7.9, 1.3 Hz, 2H), 8.18 (d, J = 6.6 Hz, 1H), 8.11 (t, J = 4.8 Hz, 4H), 8.00 (d, J = 8.0 Hz, 1H), 7.62 (ddd, J = 7.3, 5.5, 1.3 Hz, 2H), 7.31 (dt, J = 19.1, 7.7 Hz, 2H), 7.21 (d, J = 7.5 Hz, 2H), 6.95 (t, J = 7.7 Hz, 1H), 5.59 (d, J = 8.2 Hz, 1H), 1.98 (s, 6H, -CH3).

[0051] (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ Single crystal structure of ionic iridium(III) complex of configuration:

[0052] To determine the structural characteristics of ionic iridium(III) complex (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configuration in space, single crystal culture was carried out on 1a, 1b: dichloromethane was selected as a good solvent for single crystal culture of 1a, 1b; n-hexane and n-pentane were non-good solvents for 1a, 1b, respectively, and orange cuboid crystals and red cuboid crystals were obtained by natural evaporation. Single crystal data collected by X-ray single crystal diffractometer were analyzed by OLEX-2.15, and the crystal structure was drawn using diamond-4.0. The crystal structures of 1a, 1b are shown in Figure 5 , Figure 6 .

[0053] (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ Photophysical properties of ionic iridium(III) complex of configuration:

[0054] As shown in Figure 7 , the photophysical properties of ionic iridium(III) complex (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configuration (1a) and (1b) (10 -5M) Absorption peaks in CH2Cl2solution at 230, 262, 335, 432, 498 nm and 230, 276, 369, 460, 510 nm, respectively.

[0055] As shown in Figure 8 Figure 1, the ionic iridium(III) complexes of (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configurations (1a) and (1b) (10 -5 M) Maximum emission peaks in CH2Cl2solution at 650, 703 (sh) nm and 657, 718 (sh) nm, respectively.

[0056] (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ Cytotoxicity test of the ionic iridium(III) complexes of (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)]

[0057] The anti-tumor activity of the ionic iridium(III) complexes of (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configurations against human lung cancer cell line (A549), human colon cancer cell line (HCT116) and human liver cancer cell (BEL-7402). The ionic iridium(III) complexes of (+3, +2, +1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ configurations were dissolved in DMSO (less than 0.05%) and incubated with cells for 48 h, stained with 10% MTT for 6 h, and then 100 μL DMSO was added to dissolve the purple formic acid product. Finally, the absorbance value at 570 nm was determined by a microplate reader. The difference between the photodynamic cytotoxicity test and the above operation is that after the iridium(III) complexes were incubated with cells for 5 h, the plate cover was removed and irradiated with an incandescent lamp (380 nm-780 nm) for 45 min at room temperature, and then the incubation was continued for 48 h, and the subsequent operation was the same as above.

[0058] The anti-tumor activity of Examples 1a and 1b is as follows:

[0059] Table 1 is the crystal data and structure refinement of 1a and 1b:

[0060]

[0061]

[0062] Table 2 is the main bond length of 1a and 1b and bond angles (°)

[0063]

[0064] The above specific examples include only the preferred embodiments of the present application, and therefore, equivalent forms of replacement and several improvements made under the technical support of the present application should belong to the protection scope of the present application.

Claims

1. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ Ionic iridium(III) complexes with the following configuration are characterized by: Using metal-iridium as the luminescent center, it is formed by the chelation of tridentate ligands (N^C^N or N^N^N), bidentate ligands (HC^N), and monodentate cyanide ligands (R) with iridium metal, and its general structural formula is shown in Formula 1:

2. The method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] as described in claim 1 + / 2+ Ionic iridium(III) complexes with the following configuration are characterized by: The aforementioned tridentate ligands (N^C^N or N^N^N) are various aromatic compounds with strong coordination ability and easy to functionalize by introducing target groups. The most representative of these are structures containing terpyridine. One of the following structures is selected:

3. The method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] according to claim 1. + / 2+ Ionic iridium(III) complexes with the following configuration are characterized by: The aforementioned bidentate ligand (HC^N) is selected with an electron-rich pyridine-thiophene structure, which is beneficial for increasing the energy level of the highest occupied orbital (HOMO), thereby reducing the band gap (E). g This causes a red shift in the emission wavelength, and can be achieved by selecting one of the following structures:

4. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] as described in claim 1. + / 2+ Ionic iridium(III) complexes with the following configuration are characterized by: The monodentate ligand-selective isocyanate compound is selected from one of the following structures:

5. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ The method for preparing ionic iridium(III) complexes with the following configuration is characterized by, The synthesis route is as follows:

6. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ The method for preparing ionic iridium(III) complexes with the following configuration is characterized by, Includes the following steps: Step 1, prepare the bridging intermediate {[Ir(N^C^N)Cl(μ - [Ir(N^C^N)Cl(μ-Cl)]2}: In a mixed solvent of ethylene glycol monoethyl ether and deionized water, a mixture of tridentate ligand (N^C^N) and iridium chloride trihydrate is added, and the mixture is placed under inert nitrogen gas at 110 °C to obtain the bridging intermediate {[Ir(N^C^N)Cl(μ-Cl)]2}; Step 2, Preparation of [Ir(N^C^N)(C^N)(Cl)] type neutral iridium(III) complex: In a toluene system, in the presence of silver trifluoromethanesulfonate, the bridging intermediate and the bidentate ligand (HC^N) were placed under inert nitrogen gas and reacted at 110 °C to obtain the [Ir(N^C^N)(C^N)(Cl)] type neutral iridium(III) complex; Step 3, prepare [Ir(N^C^N)(C^N)(R)] + Ionic iridium(III) complexes: In a methanol system, in the presence of silver trifluoromethanesulfonate, the neutral iridium(III) complex of type [Ir(N^C^N)(C^N)(Cl)] purified by silica gel column chromatography in the previous step was reacted with a monodentate cyanide ligand R under inert nitrogen atmosphere at 65°C in the dark to obtain [Ir(N^C^N)(C^N)(R)]. + Ionic iridium(III) complexes with the following configuration.

7. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] according to claim 6. + / 2+ The method for preparing ionic iridium(III) complexes with the following configuration is characterized by, In step 1, the molar ratio of the tridentate ligand (N^C^N) and iridium chloride trihydrate is 1.1:1; in step 2, the molar ratio of the bridging intermediate and the bidentate ligand (HC^N) is 1:2.5; and in step 3, the molar ratio of the [Ir(N^C^N)(C^N)(Cl)] type neutral iridium(III) complex and the monodentate cyanide ligand R is 1:2.

5.

8. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ The method for preparing ionic iridium(III) complexes with the following configuration is characterized by, Includes the following steps: Step 1, Preparation of intermediate {[Ir(N^N^N)Cl3]}: Add a mixture of tridentate ligand (N^N^N) and iridium chloride trihydrate to ethylene glycol, and place it under inert nitrogen gas conditions, reacting at 160°C in the dark to obtain intermediate {[Ir(N^N^N)Cl3]}. Step 2, prepare [Ir(N^N^N)(C^N)(Cl)] + Ionic iridium(III) complexes: In ethylene glycol, the intermediate {[Ir(N^N^N)Cl3]} and the bidentate ligand (HC^N) are placed under an inert nitrogen atmosphere and reacted in the dark at 180°C to obtain neutral iridium(III) complexes of type [Ir(N^C^N)(C^N)(Cl)]. Step 3, prepare [Ir(N^N^N)(C^N)(R)] 2+ Type ionic iridium(III) complexes: In a methanol system, in the presence of silver trifluoromethanesulfonate, the [Ir(N^N^N)(C^N)(Cl)] purified by silica gel column chromatography in the previous step was... + The ionic iridium(III) complex reacted with a monodentate cyanide ligand R under inert nitrogen atmosphere at 65°C in the dark to yield [Ir(N^N^N)(C^N)(R)]. 2+ Ionic iridium(III) complexes with the following configuration.

9. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] according to claim 6. + / 2+ The method for preparing ionic iridium(III) complexes with the following configuration is characterized by, In step 1, the molar ratio of the tridentate ligand (N^N^N) and iridium chloride trihydrate is 1.1:1; in step 2, the molar ratio of the intermediate and the bidentate ligand (HC^N) is 1:1.1; in step 3, [Ir(N^N^N)(C^N)(Cl)] + The molar ratio of the ionic iridium(III) complex to the monodentate cyanide ligand R is 1:2.

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10. A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] according to claim 1. + / 2+ The method for preparing ionic iridium(III) complexes with the following configuration is characterized by, A method based on (+3,+2,+1)-[Ir(N^C^N / N^N^N)(C^N)(R)] + / 2+ Applications of ionic iridium(III) complexes in antitumor activity: The inhibitory effects on tumor cells such as lung cancer cells, colon cancer cells, and liver cancer cells were tested using the conventional MTT assay.

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