Ring metal iridium complex carbon monoxide donor as well as preparation method and application thereof
By designing a cyclic iridium complex carbon monoxide donor, and utilizing iron ions and hydrogen peroxide activation, the controlled release and visual monitoring of carbon monoxide are achieved, solving the problems of poor stability and uncontrolled release in existing technologies, and improving the safety and controllability of treatment.
Patent Information
- Application Number
- CN202511790207.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-01
- Publication Date
- 2026-02-10
AI Technical Summary
Existing carbon monoxide donors are unstable, difficult to store, and their release is uncontrolled and cannot be monitored in real time, failing to meet the needs for safe and controllable disease treatment.
A cyclic metal iridium complex carbon monoxide donor was developed, which enables the controlled release of carbon monoxide through activation by intracellular iron ions and low concentrations of hydrogen peroxide, and allows for visual monitoring using fluorescence changes.
It enables controlled release and visual monitoring of carbon monoxide, improving the safety and controllability of the treatment process and helping to understand the disease process.
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Figure CN121494898A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of organometallic complexes, in particular to a cyclometalated iridium complex carbon monoxide donor, a preparation method and application thereof. BACKGROUND
[0002] Carbon monoxide in the environment is mainly due to incomplete combustion of fossil energy and other colorless, odorless toxic gases. This gas is difficult to react with other substances at room temperature, so it can remain in the environment for a long time. As one of the atmospheric pollutants, it has a great influence on animal and human health. Studies have shown that carbon monoxide has a certain effect on reducing blood pressure in vasodilation and hypertension. At the same time, carbon monoxide also has anti-inflammatory effects and plays a positive role in anti-apoptosis and cancer treatment. However, if endogenous carbon monoxide metabolism is abnormal, it will cause many pathological reactions. For example, hypertension, inflammatory response, heart failure, etc. Carbon monoxide has many positive and negative effects on the human body. In the body, there are at least two ways to produce endogenous carbon monoxide. The first is oxidation of organic molecules; 1) microsomal lipid peroxidation dependent on nicotinamide adenine dinucleotide phosphate (NADPH); 2) autoxidation of phenol and methane salt; 3) photoelectric oxidation of organic compounds. The second is produced by heme oxygenase catalytic metabolism. Heme oxygenase has three subtypes in mammals: HO-1, HO-2 and HO-3. Heme oxygenase catalyzes the oxygen addition reaction of the heme porphyrin ring, which makes the alpha-mid carbon bridge oxidize and break, generating the same proportion of carbon monoxide, BV and divalent iron ions.
[0003] Carbon monoxide, as an important signaling molecule in the human body, plays an important role in neural transmission and cancer treatment. In particular, abnormal carbon monoxide concentration in the body is related to the occurrence of many diseases. Therefore, a carbon monoxide donor that can safely and non-toxically release carbon monoxide is of great significance for cancer mechanism exploration and treatment, and visualization of the carbon monoxide release process helps to understand the process of carbon monoxide acting on diseases. The main carbon monoxide donors on the market are CORM-2 and CORM-3, but they have the disadvantages of poor stability, difficulty in storage, uncontrolled carbon monoxide release, poor cell uptake, etc., and cannot be monitored in real time using visual monitoring means to monitor the amount of carbon monoxide release, so the carbon monoxide release cannot be controlled. Therefore, it is necessary to develop a stable and controllable, safe and non-toxic carbon monoxide donor to meet the demand.
[0004] In view of the above defects, the present inventors have finally obtained the present application after long-term research and practice. SUMMARY
[0005] The present application aims to solve the problems of poor stability, poor storage, uncontrolled carbon monoxide release, poor cell uptake, and the inability to observe the carbon monoxide release process in real time, and to help doctors understand the process of carbon monoxide acting on diseases. Therefore, the present application provides a new cyclometalated iridium complex carbon monoxide donor, a preparation method and applications thereof. The cyclometalated iridium complex carbon monoxide donor prepared by the present application can be activated by intracellular iron ions and low content hydrogen peroxide, thereby releasing carbon monoxide at the lesion site, and as the carbon monoxide is released, the iridium complex fluorescence gradually increases, which can realize the visualization of diseases.
[0006] In order to achieve the above-mentioned purpose, the present application discloses a cyclometalated iridium complex carbon monoxide donor, which is a flavonoid phenylpyridine-4,7-diphenyl phenanthroline-iridium complex, and its structural formula is as follows:
[0007] .
[0008] The present application also discloses a preparation method of the cyclometalated iridium complex carbon monoxide donor, comprising the following steps:
[0009] S1, 4-(2-pyridyl)benzaldehyde and 2-hydroxyacetophenone are reacted with potassium hydroxide aqueous solution at room temperature in methanol as a solvent, then 10% hydrogen peroxide solution is added for ice bath reaction, and after filtration and drying, a light yellow solid is obtained, which is a flavonoid phenylpyridine, denoted as precursor 1;
[0010] S2, iridium trichloride and precursor 1 are reacted with ethylene glycol ethyl ether and water as solvents, and after the reaction is completed, the orange solid cyclometalated iridium complex precursor is obtained by filtration and drying, denoted as precursor 2;
[0011] S3, 4,7-diphenyl-1,10-phenanthroline and precursor 2 are reacted with dichloromethane and methanol as reaction solvents, and after the reaction is completed, the product, i.e. the cyclometalated iridium complex carbon monoxide donor, is obtained after rotary evaporation of the solvent, separation and purification. Compared with the conventional iridium complex purification method, this method does not require column chromatography and is simple and fast.
[0012] In the step S1, the molar ratio of 4-(2-pyridyl)benzaldehyde to 2-hydroxyacetophenone is 1:1, the volume ratio of methanol to potassium hydroxide aqueous solution is 20:1, and the concentration of potassium hydroxide aqueous solution is 1g / mL.
[0013] In the step S1, the room temperature reaction time is 24 h, and the ice bath time is 12 h.
[0014] In the step S2, the molar ratio of iridium trichloride to precursor 1 is 1:2, and the volume ratio of ethylene glycol ethyl ether to water is 3:1.
[0015] In step S2, the heating reaction temperature is 135 °C and the reaction time is 48 h.
[0016] In step S3, the molar ratio of 4,7-diphenyl-1,10-phenanthroline to precursor 2 is 3:1, and the volume ratio of dichloromethane to methanol solvent is 1:1.
[0017] In step S3, the heating reaction temperature is 70 °C and the reaction time is 24 h.
[0018] In step S3, the separation and purification are as follows: the reaction solution is distilled under reduced pressure and washed multiple times with petroleum ether. Compared with conventional iridium complex purification methods, this method does not require column chromatography and is simple and fast.
[0019] The synthesis route is as follows:
[0020]
[0021]
[0022]
[0023] The present invention also discloses the application of the above-mentioned cyclic metal iridium complex carbon monoxide donor in the controlled release and visualization of carbon monoxide.
[0024] This invention utilizes the mechanism that flavonoid phenylpyridine iridium complexes release carbon monoxide under reactive oxygen species stimulation, and their structural changes lead to enhanced fluorescence. A flavonoid phenylpyridine iridium complex was designed that can simultaneously monitor carbon monoxide release in real time and release it rapidly and efficiently. A key feature is that its fluorescence intensity increases with the gradual increase of hydrogen peroxide and ferrous ion concentrations, meaning the degree of structural change is related to the hydrogen peroxide concentration. This not only achieves controllable carbon monoxide release but also enables visualization.
[0025] The carbon monoxide release reaction is as follows:
[0026] .
[0027] Compared with existing technologies, the advantages of this invention are as follows: the iridium complex in this invention can release carbon monoxide under the action of hydrogen peroxide and ferrous ions. Simultaneously, the structure of the iridium complex changes during the release of carbon monoxide, leading to a change in its fluorescence intensity. Therefore, the degree of release can be judged based on the change in fluorescence intensity, and the process can be stopped at any time, resulting in a high degree of controllability. Attached Figure Description
[0028] Figure 1 This is the mass spectrum of flavonoid phenylpyridine ligands;
[0029] Figure 2The spectral diagram of the flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex;
[0030] Figure 3 It is a flavonoid phenylpyridine ligand. 1 H NMR spectrum;
[0031] Figure 4 It is a hydroxyflavonoid phenylpyridine-diphenyl-o-phenanthroline-iridium complex. 1 H NMR spectrum;
[0032] Figure 5 The UV absorption (A) and fluorescence spectra (B) of the iridium complex in different solvents are shown.
[0033] Figure 6 The UV absorption (A) and fluorescence spectra (B) of iridium complexes stimulated by different concentrations of hydrogen peroxide are shown.
[0034] Figure 7 Mass spectrum of iridium complex after hydrogen peroxide catalysis;
[0035] Figure 8 Fluorescence spectra of ferrous sulfate (A) and hydrogen peroxide (B) at different concentrations reacting alone with iridium complexes;
[0036] Figure 9 The determination of carbon monoxide levels produced by iridium complexes under different concentrations of hydrogen peroxide stimulation. Detailed Implementation
[0037] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.
[0038] Example 1
[0039] Synthesis of carbon monoxide donor for flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex:
[0040] Weigh 2g of 4-(2-pyridyl)benzaldehyde and 1.34mL of 2-hydroxyacetophenone. Using 20mL of methanol as solvent, add 1mL of 1g / mL potassium hydroxide aqueous solution and react at room temperature for 24h. Then add 4mL of 10% hydrogen peroxide solution and react in an ice bath for 12h. After filtration and drying, a light yellow solid flavonoid phenylpyridine is obtained, denoted as precursor 1.
[0041] 164 mg of iridium trichloride and 300 mg of precursor 1 were weighed into a round-bottom flask. 15 mL of ethylene glycol ethyl ether and 5 mL of water were added as solvents. The mixture was heated at 135 °C for 48 h. After the reaction was complete, the mixture was cooled to room temperature and filtered to obtain an orange solid cyclic metallic iridium complex precursor, denoted as precursor 2.
[0042] 90 mg of 4,7-diphenyl-1,10-phenanthroline and 150 mg of precursor 2 were weighed into a round-bottom flask. 20 mL of dichloromethane and 20 mL of methanol were added as reaction solvents. The mixture was heated at 70 °C for 24 h. After the reaction was complete, the solvent was evaporated to dryness. The residue of 4,7-diphenyl-1,10-phenanthroline was removed by slurrying with petroleum ether, and then dried to obtain a pure orange-yellow solid, namely the flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex.
[0043] Mass spectrometry spectrum 1 The H NMR spectra are shown below. Figure 1 , Figure 2 and Figure 3 , Figure 4 As shown, flavonoid phenylpyridine ligands ( Figure 1 The theoretical molecular mass of is 315, while the actual molecular mass is 316. The flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex ( Figure 2 The theoretical molecular mass of ) is 1153, and the actual mass spectrum is 1153, which confirms that it is the correct synthetic product.
[0044] Example 2
[0045] UV absorption and fluorescence intensity of the carbon monoxide donor of the flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex in different solvents:
[0046] Weigh out the iridium complex solid and dissolve it in dimethyl sulfoxide to obtain a 10 mM iridium complex stock solution. Take 4 μL of the stock solution into a centrifuge tube, and dilute the iridium complex to a concentration of 40 μM by adding methanol, water, PBS, and acetonitrile, respectively. Transfer the liquid from the centrifuge tube to a 96-well black plate and perform fluorescence analysis using a microplate reader (immobilization excitation: 405 nm, emission start: 450 nm, stop: 700 nm, step: 2 nm). After detecting the fluorescence intensity, immediately transfer the liquid from the black plate to a transparent 96-well plate to test the UV absorption. See [link to microplate]. Figure 5 As shown.
[0047] The results are as follows Figure 5 As shown, the fluorescence intensity of the iridium complex is significantly enhanced in methanol and acetonitrile solvents, while the fluorescence intensity is almost the same in other solvents.
[0048] Example 3
[0049] Fluorescence and UV absorption spectra of the flavonoid phenylpyridine-4,7-diphenyl-1,2-phenanthroline-iridium complex under hydrogen peroxide stimulation:
[0050] Weigh out the iridium complex and prepare a 10 mM stock solution using dimethyl sulfoxide (DMSO) as the solvent. Take 4 μL of the stock solution into a centrifuge tube, add 10 μL of DMSO to aid dissolution, add 25 μL of a 1 mM ferrous sulfate aqueous solution, and then add 0, 2, 4, 6, 8, and 10 μL of a 10 mM hydrogen peroxide solution, respectively. Finally, add ultrapure water to bring the volume to 1 mL and incubate at 37 ℃ for 2.5 h. Transfer the liquid from the centrifuge tube to a 96-well black plate and perform fluorescence analysis using a microplate reader (immobilization excitation: 405 nm, emission start: 450 nm, stop: 700 nm, step: 2 nm). After detecting the fluorescence intensity, immediately transfer the liquid from the black plate to a transparent 96-well plate to test the UV absorption. See [link to microplate]. Figure 6 As shown.
[0051] The results are as follows Figure 6 As shown, the fluorescence intensity of the iridium complex increases with increasing hydrogen peroxide concentration, while the UV absorption at 450 nm shows a decreasing trend. This indicates that hydrogen peroxide, with the assistance of ferrous ions, can catalyze structural changes in the iridium complex. Figure 1 , Figure 2 and Figure 7 This further demonstrates that the structure of the iridium complex changed under the catalysis of ferrous ions and hydrogen peroxide.
[0052] Example 4
[0053] Fluorescence spectra of ferrous sulfate and hydrogen peroxide reacting alone with iridium complexes at different concentrations:
[0054] Weigh out the iridium complex and prepare a 10 mM stock solution using dimethyl sulfoxide (DMSO) as the solvent. Take 4 μL of the stock solution into a centrifuge tube, add 10 μL of DMSO to aid dissolution, and then add 0, 5, 10, 20, 30, 40, and 50 μL of 1 mM ferrous sulfate aqueous solution, respectively. Finally, add ultrapure water to bring the volume to 1 mL and incubate at 37 ℃ for 2.5 h. Transfer the liquid from the centrifuge tube to a 96-well black plate and perform fluorescence analysis using a microplate reader (immobilization excitation: 405 nm, emission start: 450 nm, stop: 700 nm, step: 2 nm). See [link to microplate reader]. Figure 8 (A).
[0055] Take another 4 μL of the stock solution and place it in a centrifuge tube. Add 10 μL of dimethyl sulfoxide to aid dissolution. Then add 0, 5, 10, 20, 30, 40, and 50 μL of 10 mM hydrogen peroxide solution, respectively. Finally, add ultrapure water to bring the volume to 1 mL and incubate at 37 ℃ for 2.5 h. Transfer the liquid from the centrifuge tube to a 96-well black plate and perform fluorescence analysis using a microplate reader (immobilization excitation: 405 nm, emission start: 450 nm, stop: 700 nm, step: 2 nm). See [link to microplate reader]. Figure 8 (B).
[0056] The results are as follows Figure 8 As shown, under conditions where the concentrations of ferrous ions and hydrogen peroxide were changed individually, the fluorescence intensity of the flavonoid phenylpyridine-4,7-diphenyl-1,2-phenanthroline-iridium complex remained almost unchanged, compared to... Figure 6 (B) further illustrates that single ferrous ions and hydrogen peroxide cannot cause changes in the structure of iridium complexes, thereby producing carbon monoxide.
[0057] Example 5
[0058] Determination of carbon monoxide levels produced by the flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex under different concentrations of hydrogen peroxide stimulation:
[0059] Weigh out the iridium complex and prepare a 10 mM stock solution using dimethyl sulfoxide (DMSO) as the solvent. Take 4 μL of the stock solution into a centrifuge tube, add 10 μL of DMSO to aid dissolution, then add 25 μL of a 1 mM ferrous sulfate aqueous solution and 10 μL of a 1 mM palladium chloride solution. Next, add 0, 2, 4, 6, 8, 10, and 20 μL of a 10 mM hydrogen peroxide solution, respectively. Add ultrapure water to bring the volume to 1 mL and incubate overnight at 37 °C. Then add 1 μL of a 10 mM carbon monoxide fluorescent probe stock solution and incubate at 37 °C for 4 h. Transfer the liquid from the centrifuge tube to a slit-slit quartz dish and perform fluorescence analysis using a fluorescence scanner (fixed excitation: 560 nm, emission start: 600 nm, stop: 900 nm, step size: 2 nm).
[0060] The results are as follows Figure 9 As shown, with the assistance of ferrous ions, the fluorescence intensity of the CO fluorescent probe at 700 nm increases with the increase of hydrogen peroxide concentration, indicating that the amount of CO produced by the flavonoid phenylpyridine-4,7-diphenyl-1,2-phenanthroline-iridium complex is gradually increasing.
[0061] The above description is merely a preferred embodiment of the present invention and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.
Claims
1. A cyclic metal iridium complex carbon monoxide donor, characterized in that, Its full name is flavonoid phenylpyridine-4,7-diphenyl-o-phenanthroline-iridium complex, and its structural formula is shown below: 。 2. A method for preparing the cyclic metal iridium complex carbon monoxide donor as described in claim 1, characterized in that, Includes the following steps: S1, 4-(2-pyridyl)benzaldehyde and 2-hydroxyacetophenone were reacted with potassium hydroxide aqueous solution in methanol at room temperature, and then reacted with 10% hydrogen peroxide solution in an ice bath. After filtration and drying, a light yellow solid was obtained, which is the flavonoid phenylpyridine, denoted as precursor 1. S2, Iridium trichloride and precursor 1 were reacted with ethylene glycol ethyl ether and water as solvents by heating. After the reaction was completed, the mixture was filtered and dried to obtain an orange solid cyclic metal iridium complex precursor, denoted as precursor 2. S3, 4,7-diphenyl-1,10-phenanthroline and precursor 2 were reacted with dichloromethane and methanol as solvents under heating. After the reaction was completed, the solvent was removed by rotary evaporation. 100 mL of petroleum ether was added to the reaction flask, and the mixture was sonicated for 10 min. After the solid product was fully dispersed in the petroleum ether, it was filtered using a Buchner funnel to remove the petroleum ether, thereby removing unreacted 4,7-diphenyl-1,10-phenanthroline. The dispersion and filtration were repeated 5 times. The filter cake was then dried in a 75 °C oven to obtain the product, namely the cyclic metal iridium complex carbon monoxide donor.
3. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S1, the molar ratio of 4-(2-pyridyl)benzaldehyde to 2-hydroxyacetophenone is 1:1, the volume ratio of methanol to potassium hydroxide aqueous solution is 20:1, and the concentration of potassium hydroxide aqueous solution is 1 g / mL.
4. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S1, the reaction time at room temperature is 24 hours and the ice bath time is 12 hours.
5. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S2, the molar ratio of iridium trichloride to precursor 1 is 1:2, and the volume ratio of ethylene glycol ethyl ether to water is 3:
1.
6. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S2, the heating reaction temperature is 135 °C and the reaction time is 48 h.
7. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S3, the molar ratio of 4,7-diphenyl-1,10-phenanthroline to precursor 2 is 3:1, and the volume ratio of dichloromethane to methanol solvent is 1:
1.
8. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S3, the heating reaction temperature is 70 °C and the reaction time is 24 h.
9. The method for preparing a cyclic metal iridium complex carbon monoxide donor as described in claim 2, characterized in that, In step S3, the separation and purification are as follows: the reaction solution is distilled under reduced pressure, and the product is obtained by washing it multiple times with petroleum ether.
10. The application of the cyclic metal iridium complex carbon monoxide donor as described in claim 1 in the controlled release and visualization of carbon monoxide.