Photo-activated carbonyl manganese (I) complex and preparation method and antibacterial application thereof
By synthesizing photoactivated manganese carbonyl (I) complexes and using white light to activate CO, the problem of combining photoactivated therapy with CO gas therapy in the prior art is solved, and the efficient antibacterial effect on Mycobacterium smegmatis is achieved.
Patent Information
- Application Number
- CN202510978786.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-16
- Publication Date
- 2025-08-15
- Estimated Expiration
- 2045-07-16
AI Technical Summary
The existing antibacterial methods are difficult to effectively combine photoactive therapy with CO gas therapy, and Mn-CORMs have problems with CO release rate and energy requirements in photochemical treatment.
A photoactivated manganese carbonyl (I) complex was designed to synthesize photoactivated ligands and complexes through specific steps, and use white light to release CO, combined with 4,4'-dimethoxy-4'-borate trianiline to participate in the reaction, expand the light response range, and achieve efficient CO release.
Under white light irradiation, the photo-activated manganese carbonyl (I) complex significantly releases CO, showing excellent antibacterial toxicity to Mycobacterium smegmatis, and the CO probe detects the production of CO under light, achieving targeted treatment for specific bacteria.
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Figure CN120484024A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of medicinal chemistry, and in particular to a photoactivated carbonyl manganese (I) complex, a preparation method thereof, and an application thereof in antibacterial treatment. Background Art
[0002] Antimicrobial photoactivation therapy is an emerging therapeutic approach that has attracted considerable attention in medicine in recent years. Recently, metal complexes have emerged as promising antibiotics and effective means of combating various bacterial infections. Concurrently, carbon monoxide (CO) gas therapy has also shown potential in antimicrobial research. Several metal-based CO-releasing molecules (CORMs) are compounds capable of releasing CO in response to specific stimuli, such as light or ultrasound. Therefore, the development of a metal complex capable of combining photoactivation therapy with CO gas therapy would be of great interest.
[0003] Compared to other heavy metal-based CORMs, Mn-CORMs offer several unique advantages in photochemotherapy. First, Mn-CO complexes exhibit a low-energy MLCT (metal-to-ligand charge transfer) transition. Second, Mn-CORMs can be activated by relatively low-energy visible light to release CO, facilitating photoactivated therapy. Furthermore, Mn-CORMs exhibit a rapid CO release rate, enabling more effective targeted therapy. To achieve a combined antibacterial strategy of photoactivated therapy and gas therapy, we designed a Mn-CORM that can photorelease CO and a ligand. Summary of the Invention
[0004] A photoactivated carbonyl manganese(I) complex, .
[0005] A method for preparing a photoactivated carbonyl manganese (I) complex comprises the following steps: S1. reacting 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole to obtain product 1; S2. reacting product 1 with 4,4'-dimethoxy-4''-triphenylamine borate to prepare a photoactivated ligand; S3. React Mn(CO)5Br with a photoactivated ligand to prepare a photoactivated carbonyl manganese (I) complex.
[0006] As an optimization, the following steps are included: S1. Preparation of product 1, the reaction is as follows: ; S2. Preparation of photoactivatable ligand, the reaction is as follows: ; S3. Preparation of photoactivated carbonyl manganese (I) complexes, reaction as follows: .
[0007] As an optimization, the following steps are included: S1. 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole were added to dry toluene, heated under reflux for 12-24 hours under a nitrogen atmosphere, cooled to room temperature, filtered, evaporated under reduced pressure, and separated and purified by silica gel column to obtain product 1; S2. Add product 1, 4,4'-dimethoxy-4''-triphenylamine borate, potassium carbonate, and (1,1'-bis(diphenylphosphino)ferrocene)palladium dichloride to a solvent, heat to a slight boiling point and reflux for 10-20 hours, distill under reduced pressure, and separate and purify by silica gel column to obtain a photoactivated ligand; S3. In a nitrogen atmosphere, in the dark, dissolve pentacarbonyl manganese bromide and silver trifluoromethanesulfonate in dry acetone, stir and reflux at 60°C for 2 to 6 hours, filter and collect the filtrate, add the photoactivated ligand to the filtrate, then add dry acetone, stir and reflux at 60°C for 2 to 6 hours, filter, wash with dry ether and dry to obtain a photoactivated carbonyl manganese (I) complex.
[0008] As an optimization, the molar ratio of 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole in S1 is 1:1; and the amount of toluene used is 10 to 20 times the total mass of 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole.
[0009] As an optimization, the eluent used for separation and purification by silica gel column in S1 and S2 is a mixture of dichloromethane and methanol in a mass ratio of 20:1.
[0010] As an optimization, the molar ratio of the product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene)palladium dichloride in S2 is 1:1:5:0.1; the solvent is a mixture of toluene and methanol in a volume ratio of 1:1, and the amount used is 10 to 20 times the total mass of the product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene)palladium dichloride.
[0011] As an optimization, the molar ratio of pentacarbonyl manganese bromide, silver trifluoromethanesulfonate and photoactivated ligand in S3 is 1:1:1; the amount of dry acetone used is 10 to 20 times the total mass of pentacarbonyl manganese bromide, silver trifluoromethanesulfonate and photoactivated ligand, and is used twice, half of which is used each time.
[0012] Application of photoactivated manganese(I) carbonyl complexes in the photoactivated production of carbon monoxide.
[0013] Antibacterial applications of photoactivated carbonyl manganese(I) complexes.
[0014] Compared with the prior art, the present invention has the following technical effects: The present invention incorporates 4,4'-dimethoxy-4''-triphenylamine borate into the reaction, increasing the light response range. This allows the carbonyl manganese(I) complex to produce CO under white light, as confirmed by the Hb assay. Furthermore, the UV-visible absorption spectrum changes significantly before and after illumination, suggesting the possibility of ligand release. In antibacterial experiments, the carbonyl manganese(I) complex exhibited excellent antimicrobial toxicity against Mycobacterium smegmatis, and CO production by Mn-ATA under illumination was also detected in M. smegmatis using the CO probe COP-2. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In the accompanying drawings, ATA represents a photoactivated ligand, and Mn-ATA represents a photoactivated manganese carbonyl (I) complex; Figure 1 Flow chart for the preparation of the photoactivated carbonyl manganese (I) complex of the present invention; Figure 2 H NMR spectrum of the photoactivated carbonyl manganese (I) complex of the present invention in DMSO-d6; Figure 3 Mass spectrum of the photoactivated carbonyl manganese (I) complex of the present invention in methanol / water as the mobile phase; Figure 4 The carbon spectrum of the photoactivated carbonyl manganese (I) complex of the present invention in deuterated chloroform; Figure 5 Changes in the UV-visible absorption spectrum of the photoactivated carbonyl manganese (I) complex of the present invention before and after irradiation in a DMSO / water system; Figure 6 The Hb method shows the CO signal generated by the photoactivated carbonyl manganese (I) complex under white light irradiation in the UV-visible absorption spectrum; Figure 7 The phototoxicity and dark toxicity of the photoactivated carbonyl manganese (I) complex of the present invention to Mycobacterium smegmatis; Figure 8 The phototoxicity and dark toxicity of the photoactivated carbonyl manganese (I) complex of the present invention to Escherichia coli; Figure 9 The phototoxicity and dark toxicity of the photoactivated carbonyl manganese (I) complex of the present invention to Staphylococcus aureus; Figure 10 The production of CO in cells after the photoactivated carbonyl manganese (I) complex of the present invention is irradiated with white light. DETAILED DESCRIPTION
[0016] To make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be described in detail below with reference to specific embodiments and comparisons. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0017] Unless otherwise specified, the equipment used in this example is conventional experimental equipment, the materials and reagents used are commercially available unless otherwise specified, and the experimental methods without special instructions are also conventional experimental methods.
[0018] Example 1 Synthesis of Photoactivated Carbonyl Manganese (I) Complex: S1. 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole were added to dry toluene, heated under reflux for 12 hours under a nitrogen atmosphere, cooled to room temperature, filtered, distilled under reduced pressure, and separated and purified on a silica gel column to obtain product 1; the molar ratio of the 2,2'-dipicolylamine to the 4,7-dibromo-2,1,3-benzothiadiazole was 1:1; the amount of toluene was 20 times the total mass of the 2,2'-dipicolylamine and the 4,7-dibromo-2,1,3-benzothiadiazole; S2. Add product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene) palladium dichloride to a solvent, heat to a slight boiling reflux for 12 hours, distill under reduced pressure and separate and purify by silica gel column to obtain a photoactivated ligand; the molar ratio of the product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene) palladium dichloride is 1:1:5:0.1; the solvent is a mixture of toluene and methanol in a volume ratio of 1:1, and the amount used is 20 times the total mass of the product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene) palladium dichloride; S3. In a nitrogen atmosphere, in the dark, dissolve pentacarbonyl manganese bromide and silver trifluoromethanesulfonate in dry acetone, stir and reflux at 60°C for 2 hours, filter and collect the filtrate, add a photoactivated ligand to the filtrate, add dry acetone, stir and reflux at 60°C for 2 hours, filter, wash with dry ether and dry to obtain a photoactivated carbonyl manganese (I) complex; the molar ratio of pentacarbonyl manganese bromide, silver trifluoromethanesulfonate and photoactivated ligand is 1:1:1; the amount of dry acetone used is 20 times the total mass of pentacarbonyl manganese bromide, silver trifluoromethanesulfonate and photoactivated ligand, and is used twice, with half of the acetone used each time.
[0019] The obtained photoactivated carbonyl manganese (I) complex is a yellow powder and is characterized as follows Figures 2-4 shown. 1 H NMR (500 MHz, DMSO- d 6): 9.03 - 8.98 (m, 2H), 8.17 - 8.10 (m, 3H), 7.93 (d, J = 8.0 Hz,1H), 7.92 - 7.88 (m, 2H), 7.64 (dd, J = 7.9, 5.1 Hz, 4H), 7.14 - for C41H32MnN6O5S [M-OTf-]+: 775.15, found: 774.8.
[0020] Test Example 1 UV-visible absorption and emission spectra of photoactivated carbonyl manganese (I) complex: A DMSO / water solution (1% DMSO aqueous solution) containing 50 μM photoactivated ligand and photoactivated carbonyl manganese (I) complex was prepared, and the UV-visible absorption of the photoactivated ligand and photoactivated carbonyl manganese (I) complex in 1% DMSO aqueous solution was measured using a UV-visible absorption spectrometer (Shimadzu UV-3600PLUS); the emission spectrum of the photoactivated carbonyl manganese (I) complex in 1% DMSO aqueous solution was measured using a fluorescence spectrometer (Edinburgh FS5). The DMSO / water solution (1% DMSO aqueous solution) containing 50 μM photoactivated carbonyl manganese (I) complex was irradiated for different times, and its UV-visible absorption and emission spectra were measured respectively. As the photoactivation time increased, the UV-visible absorption of the photoactivated carbonyl manganese (I) complex gradually weakened, while the fluorescence gradually increased. This phenomenon indicates that after photoactivation, the ligand ATA in the complex fell off, resulting in weakened UV absorption and enhanced fluorescence. The UV-visible absorption and emission spectra were tested as shown below. Figure 5 shown.
[0021] Test Example 2: Determination of CO release of manganese (I) complex in solution by Hb method: In PBS, the release of CO was detected by measuring the conversion of hemoglobin (Hb) to carboxyhemoglobin (HbCO) using UV-visible absorption spectroscopy. Hemoglobin was completely dissolved in PBS (4.3 mol / L, 1 mL, pH 7.4) and then reduced with excess sodium sulfite (SDT, 3.5 mg) under a nitrogen atmosphere. 1 μM of photoactivated carbonyl manganese (I) complex was then added. After white light irradiation (14.18 W / cm²), the absorption spectrum of the solution was collected using a UV-visible absorption spectrometer. Two strong absorption bands were found at 420 nm and 432 nm, corresponding to HbCO and Hb, respectively. Figure 6 The absorption peak at 432 nm shifted to the peak at 420 nm, indicating that the photoactivated carbonyl manganese (I) complex released CO after illumination.
[0022] Test Example 3 MIC of Photoactivated Carbonyl Manganese (I) Complex 90 Determination of: The bacteria cultured overnight were dispersed in LB medium to a concentration of (6-8) × 10 5 CFU / mL. The photoactivatable ligand and the photoactivatable carbonyl manganese(I) complex were diluted in LB medium in a sterile 96-well plate. (1) For the dark-treated group, the bacteria were incubated with the photoactivatable ligand and the photoactivatable carbonyl manganese(I) complex in the dark (18 hours, 37°C). (2) For the experimental group, the bacteria were incubated with the photoactivatable ligand and the photoactivatable carbonyl manganese(I) complex (4 hours, 37°C) and then irradiated with white light (14.18 mW / cm², 30 minutes), followed by an additional 14 hours of incubation in the dark. The absorbance of all plates was measured at OD = 600 nm. The formula for the viability ratio (VR) can be expressed as the following function: VR (%) = (C-C0) / (C1-C0) × 100; Where C is the OD value of the photoactivatable ligand + white light or photoactivatable carbonyl manganese (I) complex white light treatment. C0 is the OD value of the negative control treatment. C1 is the OD value of the control group without photoactivatable ligand and photoactivatable carbonyl manganese (I) complex incubation. Figure 7 The dark toxicity and phototoxicity of the photoactivated carbonyl manganese (I) complex were 8.97 μM and 4.52 μM, respectively, showing good antibacterial toxicity. Figure 8 、 9 It was found that the photoactivated carbonyl manganese (I) complex had no obvious toxicity to Escherichia coli and Staphylococcus aureus.
[0023] It is shown that the product prepared in the example is only toxic to Mycobacterium smegmatis, but has no obvious toxicity to Escherichia coli and Staphylococcus aureus. This selective toxicity shows that our antibacterial substance has a targeted bactericidal property.
[0024] Test Example 4 Detection of CO in cells using photoactivated carbonyl manganese (I) complexes: Under white light irradiation, the release of carbon monoxide (CO) from the bacterial cells by the photoactivated carbonyl manganese (I) complex was monitored using a COP-1 fluorescent probe (500 μM stock solution prepared in DMSO). COP-1 is a switchable fluorescent probe for CO detection. 8 CFU / mL) were treated with a photoactivated carbonyl manganese(I) complex (2.5 μM) for 4 hours and washed with PBS. Subsequently, the bacteria were incubated with 10 μM COP-1 for 30 minutes in the dark and then exposed to white light irradiation (14.18 mW / cm², 30 minutes). The bacteria were immediately imaged by confocal microscopy. COP-1 was excited at 488 nm and emission light was collected at 530 ± 30 nm. Figure 10 The experiment found that the bacteria in the drug-treated light group showed green fluorescence, indicating that the photoactivated carbonyl manganese (I) complex in the bacteria released CO after illumination.
[0025] Finally, it should be noted that the above embodiments and experimental examples are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.
Claims
1. A photoactivated carbonyl manganese (I) complex, 。 2. A method for preparing the photoactivated carbonyl manganese (I) complex according to claim 1, characterized in that: The following steps are involved: S1. reacting 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole to obtain product 1; S2. reacting product 1 with 4,4'-dimethoxy-4''-triphenylamine borate to prepare a photoactivated ligand; S3. React Mn(CO)5Br with a photoactivated ligand to prepare a photoactivated carbonyl manganese (I) complex.
3. The method for preparing a photoactivated carbonyl manganese (I) complex according to claim 2, characterized in that: The following steps are involved: S1. Preparation of product 1, the reaction is as follows: ； S2. Preparation of photoactivatable ligand, the reaction is as follows: ； S3. Preparation of photoactivated carbonyl manganese (I) complexes, reaction as follows: 。 4. The method for preparing a photoactivated carbonyl manganese (I) complex according to claim 2, characterized in that: The following steps are involved: S1. 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole were added to dry toluene, heated under reflux for 12-24 hours under a nitrogen atmosphere, cooled to room temperature, filtered, evaporated under reduced pressure, and separated and purified by silica gel column to obtain product 1; S2. Add product 1, 4,4'-dimethoxy-4''-triphenylamine borate, potassium carbonate, and (1,1'-bis(diphenylphosphino)ferrocene)palladium dichloride to a solvent, heat to a slight boiling point and reflux for 10-20 hours, distill under reduced pressure, and separate and purify by silica gel column to obtain a photoactivated ligand; S3. In a nitrogen atmosphere, in the dark, dissolve pentacarbonyl manganese bromide and silver trifluoromethanesulfonate in dry acetone, stir and reflux at 60°C for 2-6 hours, filter and collect the filtrate, add the photoactivated ligand to the filtrate, then add dry acetone, stir and reflux at 60°C for 2-6 hours, filter, wash with dry ether and dry to obtain a photoactivated carbonyl manganese (I) complex.
5. The method for preparing a photoactivated carbonyl manganese (I) complex according to claim 4, characterized in that: The molar ratio of 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole in S1 is 1:1; the amount of toluene used is 10 to 20 times the total mass of 2,2'-dipicolylamine and 4,7-dibromo-2,1,3-benzothiadiazole.
6. The method for preparing a photoactivated carbonyl manganese (I) complex according to claim 4, characterized in that: The eluent used for separation and purification by silica gel column in S1 and S2 is a mixture of dichloromethane and methanol.
7. The method for preparing a photoactivated carbonyl manganese (I) complex according to claim 4, characterized in that: The molar ratio of the product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene)palladium dichloride in S2 is 1:1:5:0.1; the solvent is a mixture of toluene and methanol in a volume ratio of 1:1, and the amount used is 10 to 20 times the total mass of the product 1, 4,4'-dimethoxy-4''-boric acid triphenylamine, potassium carbonate and (1,1'-bis(diphenylphosphino)ferrocene)palladium dichloride.
8. The method for preparing a photoactivated carbonyl manganese (I) complex according to claim 4, characterized in that: The molar ratio of pentacarbonyl manganese bromide, silver trifluoromethanesulfonate and photoactivated ligand in S3 is 1:1:1; the amount of dry acetone used is 10 to 20 times the total mass of pentacarbonyl manganese bromide, silver trifluoromethanesulfonate and photoactivated ligand, and is used twice, half of which is used each time.
9. Use of the photoactivated carbonyl manganese (I) complex according to claim 1 in photoactivation to produce carbon monoxide.
10. Use of the photoactivated carbonyl manganese (I) complex according to claim 1 in antibacterial applications.