A visible light dithienylethylene switchable antibacterial agent and its preparation method and application

Abstract

The present invention belongs to the technical field of dithienylethene antibacterial agents, and provides a visible light dithienylethene switchable antibacterial agent, a preparation method thereof and an application thereof. The structural formula of the visible light dithienylethene switchable antibacterial agent of the present invention is #imgabs0##imgabs1# wherein, R1 is a chlorine atom, #imgabs2##imgabs3# R2 is #imgabs4# and n is 0, 1 or 2. The visible light dithienylethene switchable antibacterial agent prepared by the present invention has a clear structure and a high yield, up to 59%. It has good blue light and near-infrared light-controlled switching performance. Before and after blue light irradiation, the antibacterial activity against Escherichia coli can be regulated, and it can be used as a new type of switchable antibacterial agent in photopharmacological drugs. Moreover, the preparation method is simple and low in cost, and is suitable for large-scale application.

Description

Technical Field

[0001] The invention relates to the technical field of dithienylethylene antibacterial agents, and in particular to a visible light dithienylethylene switch type antibacterial agent and a preparation method and application thereof. Background Art

[0002] Bacterial resistance to traditional antibiotics is one of the most serious medical and health problems facing the world today. In the past few decades, millions of people around the world have been threatened by infectious diseases caused by bacteria, and with the emergence of multidrug-resistant bacteria, this health threat has become more severe, posing a huge challenge to clinical medicine.

[0003] Photopharmacology introduces molecular switches into drug molecules (or pharmacophores) to obtain light-controlled bioactive molecules. Before and after illumination, the molecular configuration and polarity will change to a certain extent, thus affecting its pharmacokinetic and pharmacodynamic properties, and ultimately leading to differences in the biological activities of the two optical isomers. Therefore, photopharmacology strategies are expected to achieve site-specific activation and deactivation of antibiotics, achieve the purpose of precise antibacterial treatment, avoid their large-scale accumulation in the body and the environment, and are expected to fundamentally solve the problem of antibiotic resistance.

[0004] The dithienylethylene molecular switch has gradually attracted widespread attention from scientists at home and abroad due to its excellent properties (large difference in the conjugated structure of the switch ring isomers, good thermal stability, high quantum yield, good fatigue resistance, fast light response speed, etc.). Its excellent properties are expected to make up for the shortcomings of azobenzene switch-type drugs. In recent years, research on switch-type drugs based on dithienylethylene units has been reported in the literature. However, its activity must be controlled by ultraviolet light, which seriously limits its further in vivo research and clinical application.

[0005] Visible light-controlled dithienylethylene molecular switches have attracted widespread attention due to their potential applications in super-resolution cell imaging and biomedicine. Therefore, introducing large conjugated dithienylethylene molecular switches into fluoroquinolone antibacterial drugs and developing a visible light-controlled switch-type antibacterial agent will help solve the key technical problems that limit the in vivo research and clinical application of traditional switch-type antibacterial agents in the field of photopharmacology. Summary of the invention

[0006] The purpose of the present invention is to provide a visible light dithienylethylene switch type antibacterial agent and a preparation method and application thereof in view of the deficiencies in the prior art.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0008] The present invention provides a visible light dithiophene ethylene switch type antibacterial agent, the structural formula of the visible light dithiophene ethylene switch type antibacterial agent is

[0009]

[0010] Wherein, R1 is a chlorine atom, or R2 is n is 0, 1 or 2.

[0011] The present invention also provides a method for preparing the visible light dithienylethylene switch type antibacterial agent, comprising the following steps:

[0012] Compound I, compound II, an organic solvent and an organic base are reacted, and the reaction solution is decompressed and purified in sequence to obtain a visible light dithienylethylene switchable antibacterial agent;

[0013] The structural formula of the compound I is Wherein, R1 is a chlorine atom,

[0014]

[0015] The structural formula of compound II Among them, R2 is n is 0, 1 or 2.

[0016] Preferably, the organic solvent is one or more of N,N-dimethylformamide, acetone, acetonitrile, tetrahydrofuran, 1,4-dioxane, anhydrous ethanol and methanol.

[0017] Preferably, the organic base is one or more of triethylamine, pyridine, piperidine, diethylamine, trimethylamine, diisopropylethylamine, n-butylamine, n-propylamine, sodium tert-butoxide, potassium tert-butoxide, sodium methoxide and sodium ethoxide.

[0018] Preferably, the molar volume ratio of the compound I, compound II, organic base and organic solvent is 1 mmol:1 mmol:0.2-2 mmol:20-60 mL.

[0019] Preferably, the reaction temperature is 60-80° C., the reaction time is 14-18 h, and the reaction is carried out under a nitrogen atmosphere.

[0020] Preferably, the purification method is column chromatography purification.

[0021] Preferably, the filler for column chromatography purification is silica gel, and the mesh size of the silica gel is 200-300 meshes; the eluent for column chromatography purification is dichloromethane and methanol, and the volume ratio of dichloromethane to methanol is 1-20:1.

[0022] The present invention also provides the use of the visible light dithienylethylene switch type antibacterial agent in the preparation of photopharmacological drugs.

[0023] The beneficial effects of the present invention include the following:

[0024] 1) The visible light dithienylethylene switch-type antibacterial agent prepared by the present invention has a clear structure and a high yield of up to 59%, and has good blue light and near-infrared light-controlled switching performance. Before and after blue light irradiation, the antibacterial activity of Escherichia coli can be regulated, and can be used as a new switch-type antibacterial agent in photopharmacological drugs.

[0025] 2) The method for preparing the visible light dithienylethylene switchable antibacterial agent of the present invention is simple, low-cost, and suitable for large-scale application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The photochromic properties of the visible light dithienylethylene switchable antibacterial agent prepared in Example 1 are shown in Figure 1, wherein (a) is a graph showing the change of ultraviolet absorption with blue light irradiation, (b) is a graph showing the change of ultraviolet absorption with near-infrared light irradiation, (c) is a graph showing the anti-fatigue properties, and (d) is a graph showing the change of ultraviolet absorption in different solvents;

[0027] Figure 2 The graphs are fluorescence switch performance graphs of the visible light dithienylethylene switch type antibacterial agent prepared in Example 1, wherein (a) is a graph showing the change of fluorescence emission with blue light irradiation, (b) is a graph showing the change of fluorescence emission with near-infrared light irradiation, (c) is a graph showing the change of fluorescence emission in different solvents, and (d) is a graph showing the fluorescence attenuation in different solvents;

[0028] Figure 3 The diagram is a photo-controlled antibacterial performance diagram of the visible light dithienylethylene switchable antibacterial agent prepared in Example 1, wherein (a) is the minimum inhibitory concentration of the switchable antibacterial agent and norfloxacin before and after illumination, (b) is a growth curve diagram of Escherichia coli under in-situ blue light irradiation of the switchable antibacterial agent, and (c) is a growth curve diagram of Escherichia coli under in-situ near-infrared irradiation of the switchable antibacterial agent;

[0029] Figure 4 The diagrams are molecular docking diagrams of the switch ring isomers of the visible light dithienylethylene switchable antibacterial agent obtained in Example 1 and bacterial DNA gyrase, wherein (a) is the molecular docking diagram of the open ring isomer and the DNA gyrase (seen from the front), (b) is the molecular docking diagram of the open ring isomer and the DNA gyrase (seen from the back), (c) is the molecular docking diagram of the closed ring isomer and the DNA gyrase (seen from the front), and (d) is the molecular docking diagram of the closed ring isomer and the DNA gyrase (seen from the back). DETAILED DESCRIPTION

[0030] The present invention provides a visible light dithiophene ethylene switch type antibacterial agent, the structural formula of the visible light dithiophene ethylene switch type antibacterial agent is

[0031]

[0032] Wherein, R1 is a chlorine atom, or R2 is n is 0, 1, or 2

[0033] The present invention also provides a method for preparing the visible light dithienylethylene switch type antibacterial agent, comprising the following steps:

[0034] Compound I, compound II, an organic solvent and an organic base are reacted, and the reaction solution is decompressed and purified in sequence to obtain a visible light dithienylethylene switchable antibacterial agent;

[0035] The structural formula of the compound I is Wherein, R1 is a chlorine atom,

[0036]

[0037] The structural formula of compound II Among them, R2 is n is 0, 1 or 2.

[0038] In the present invention, the organic solvent is preferably one or more of N,N-dimethylformamide, acetone, acetonitrile, tetrahydrofuran, 1,4-dioxane, anhydrous ethanol and methanol.

[0039] In the present invention, the organic base is preferably one or more of triethylamine, pyridine, piperidine, diethylamine, trimethylamine, diisopropylethylamine, n-butylamine, n-propylamine, sodium tert-butoxide, potassium tert-butoxide, sodium methoxide and sodium ethoxide.

[0040] In the present invention, the molar volume ratio of compound I, compound II, organic base and organic solvent is preferably 1mmol:1mmol:0.2-2mmol:20-60mL, more preferably 1mmol:1mmol:0.5-1.5mmol:30-50mL, and more preferably 1mmol:1mmol:1mmol:40mL.

[0041] In the present invention, the reaction temperature is preferably 60-80°C, more preferably 65-75°C, more preferably 70°C; the reaction time is preferably 14-18h, more preferably 15-17h, more preferably 16h; the reaction is preferably carried out under a nitrogen atmosphere.

[0042] In the present invention, after the reaction is completed, the reaction solution is preferably cooled, and then the solvent is removed under reduced pressure. After that, the residue is dissolved in methanol, and a saturated aqueous solution of ammonium hexafluorophosphate is added dropwise. After a large amount of solid is precipitated, suction filtration, washing and drying are performed in sequence to purify the obtained solid; the cooling temperature is preferably room temperature; the vacuum degree of the reduced pressure is preferably 0.1 to 0.3 MPa, more preferably 0.15 to 0.25 MPa, and more preferably 0.2 MPa; the washing reagent is preferably distilled water, and the number of washings is preferably 2 to 4 times, and more preferably 3 times; the drying temperature is preferably 70 to 90° C., and more preferably 80° C., and the drying time is preferably 1 to 3 h, and more preferably 1.5 to 2.5 h, and more preferably 2 h.

[0043] In the present invention, the purification method is preferably column chromatography purification.

[0044] In the present invention, the filler for column chromatography purification is preferably silica gel; the mesh number of the silica gel is preferably 200-300 mesh, more preferably 240-260 mesh, and more preferably 250 mesh; the eluent for column chromatography purification is preferably dichloromethane and methanol, and the volume ratio of dichloromethane to methanol is preferably 1-20:1, more preferably 8-15:1, and more preferably 10:1.

[0045] The present invention also provides the use of the visible light dithienylethylene switch type antibacterial agent in the preparation of photopharmacological drugs.

[0046] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0047] The vacuum degree of filtration in the embodiment is 0.05 MPa.

[0048] Example 1

[0049] 0.5mmol 0.5mmo 0.75mmol piperidine and 10mL anhydrous ethanol reacted at 80℃ and nitrogen atmosphere for 16h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.1MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 80℃ for 2h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 200 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 3:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0050]

[0051] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 51%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 1 H NMR (400MHz, DMSO) δ15.26(s,1H),9.56(s,1H),9.00(s,1H),8.87(d,J=6.4Hz,2H),8.18(d,J=5.6Hz,2H),8.10(d,J= 16.0Hz,1H),8.00(d,J=12.4Hz,1H),7.55(d,J=7.6Hz,2H),7.38(t,J=7.6Hz,2H),7.31(s,1H),7.24(s,1H),7.06(d, J=17.2Hz,1H),6.97(d,J=17.2Hz,1H),4.61(br,2H),4.50(t,J=6.4Hz,2H),3.91(br,2H),3.61(br,2H),3.35(br,4H ),3.28(br,4H),2.86-2.80(m,4H),2.05(s,3H),1.99-1.94(m,2H),1.92(s,3H),1.68(br,2H),1.43(t,J=6.8Hz,3H). 13 C NMR (100MHz, DMSO) δ176.67,166.52,153.31,149.36,144.47,139.97,139.60,137.87,137.57, 137.02,136.83,135.73,134.56,134.11,134.03,133.74,133.60,129.56,127.82,125.36,125 .27,124.71,123.79,121.36,112.03,111.87,107.69,107.17,100.00,59.41,59.26,55.17,51 .19,49.58,47.03,38.52,38.38,27.76,22.79,15.15,14.91,14.51.HRMS(ESI-TOF)m / z:[M-PF6 - ] + Calculate for C 48 H 50 FN4O3S2813.3303; found 813.3304.

[0052] Example 2

[0053] 0.5mmol 0.5mmol 0.75mmol pyridine and 15mL acetonitrile reacted at 75℃ and nitrogen atmosphere for 18h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.2MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 70℃ for 3h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 250 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 2:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0054]

[0055] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 59%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 1 H NMR(400MHz,DMSO)δ15.26(s,1H),9.53(s,1H),8.99(br,2H),8.88(br,1H),8.19 (br,1H),8.12–8.06(m,1H),8.01(br,1H),7.75(br,3H),7.52(s,1H),7.25(br,2H ),7.09–6.94(m,2H),4.62(br,2H),4.51(br,2H),3.93(br,2H),3.61(br,2H),3.3 3–3.15(m,8H),2.85(br,4H),2.00(d,J=43.6Hz,8H),1.68(br,2H),1.44(br,3H). 13 C NMR (101MHz, DMSO) δ176.65,166.59,153.17,152.16,149.10,144.46,139.86,137.88,137.72,1 37.63,137.30,137.11,136.04,135.40,134.42,134.14,133.46,127.70,126.75,126.53,125.70 ,123.78,123.32,121.43,111.87,111.50,107.57,106.42,100.00,59.77,49.55,48.31,38.54,3 8.50,38.43,38.41,38.27,22.80,15.14,14.83,14.76,14.57,14.48.HRMS(ESI-TOF)m / z:[M-PF6 - ] + Calculate for C 49 H49 F4N4O3S2881.3177; found881.3183.

[0056] Example 3

[0057] 0.5mmol 0.5mmol 1mmol diethylamine and 30mL tetrahydrofuran were reacted at 60℃ and nitrogen atmosphere for 18h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.3MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 90℃ for 1h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 300 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 8:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0058]

[0059] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 48%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 1 H NMR (400MHz, DMSO) δ15.27(s,1H),9.00(s,1H),8.88(d,J=6.3Hz,2H),8.18(br,1H),8.10(d,J=15.9Hz ,1H),7.99(br,2H),7.47(d,J=8.7Hz,2H),7.24(s,1H),7.16(s,1H),7.06(dd,J=37.9,17.7Hz,2H),6. 94(t,J=9.9Hz,2H),4.61(br,2H),4.50(br,2H),3.92(br,2H),3.77(s,3H),3.61(br,2H),3.32(br,8H ),2.93–2.71(m,4H),2.05(s,3H),2.01–1.94(m,2H),1.89(s,3H),1.68(br,2H),1.43(t,J=6.6Hz,3H). 13C NMR (100MHz, DMSO) δ176.66,166.54,159.13,154.45,151.97,149.36,149.28,144.49,144.46,1 39.95,139.61,139.04,137.92,137.58,136.99,136.64,135.83,134.50,133.54,132.84,126.80 ,126.63,123.78,123.40,121.34,119.80,114.92,111.87,107.65,55.67,49.58,47.07,38.76,3 8.53,38.37,28.17,27.86,22.80,15.16,14.98,14.89,14.81,14.44.HRMS(ESI-TOF)m / z:[M-PF6 - ] + Calculate for C 49 H 52 FN4O4S2843.3409; found 843.3404.

[0060] Example 4

[0061] 0.5mmol 0.5mmol 1mmol trimethylamine and 10mL N,N-dimethylformamide reacted at 80℃ and nitrogen atmosphere for 16h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.1MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 80℃ for 2h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 300 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 3:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0062]

[0063] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 54%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 11H NMR (400 MHz, DMSO) δ 15.29 (s, 1H), 9.00 (s, 1H), 8.89 (d, J = 6.6 Hz, 2H), 8.19 (d, J = 6.3 Hz, 2H), 8.11 (d, J = 16.0 Hz, 1H), 7.99 (d, J = 12.7 Hz, 1H), 7.21 (s, 1H), 7.02 (dd, J = 33.5, 17.6 Hz, 2H), 6.89 (s, 1H), 4.62 (d, J = 6.5 Hz, 2H), 4.51 (t, J = 6.8 Hz, 2H), 3.91 (br, 2H), 3.63 (br, 2H), 3.29 (br, 8H), 2.88–2.66 (m, 4H), 2.04 (s, 3H), 2.03–1.94 (m, 2H), 1.84 (s, 3H), 1.68 (br, 2H), 1.43 (t, J = 7.1 Hz, 3H). 13 13C NMR (100 MHz, DMSO) δ 176.67, 166.53, 158.34, 153.28, 151.90, 149.37, 144.48, 139.97, 137.58, 137.54, 137.14, 137.01, 136.83, 135.39, 134.83, 134.50, 134.47, 133.59, 133.41, 127.79, 124.24, 123.81, 121.45, 107.66, 99.87, 49.58, 46.94, 38.33, 29.42, 27.89, 22.72, 20.48, 20.02, 15.08, 14.94, 14.89, 14.28, 11.35. HRMS (ESI-TOF) m / z: [M - PF6 - + calcd for C 42 H 45 ClFN4O3S2 771.2600; found 771.2601.

[0064] Example 5

[0065] Take 0.5 mmol 0.5 mmol ​0.8mmol diisopropylethylamine and 10mL acetone reacted at 75℃ and nitrogen atmosphere for 14h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.2MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 85℃ for 1.5h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 200 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 2:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0066]

[0067] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 56%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 1 H NMR (400MHz, DMSO) δ15.11(s,1H),9.52(s,1H),8.87(d,J=6.3Hz,2H),8.71(s,1H),8.19(d,J=6.2Hz,1H),8.10( d,J=15.7Hz,1H),8.00(d,J=12.8Hz,1H),7.61(d,J=7.4Hz,1H),7.55(d,J=7.5Hz,2H),7.38(t,J=7.5Hz,2H),7. 31(s,1H),7.25(s,1H),7.02(d,J=15.9Hz,2H),4.51(s,2H),3.92(s,2H),3.84(s,1H),3.63(s,2H),3.28(s,8H) ,2.83(s,4H),2.05(s,3H),1.98(s,2H),1.92(s,3H),1.68(s,2H),1.32(d,J=6.3Hz,2H),1.23(d,J=7.7Hz,2H). 13C NMR(101MHz,DMSO)δ176.89,166.29,154.58,153.36,152.10,148.78,144.44,144.13,144.03,140.00, 139.60,139.51,137.88,137.01,136.83,135.75,134.58,134.15,134.06,133.79,133.59,129.54,127 .79,125.28,124.70,123.80,121.33,120.05,119.97,111.85,111.63,107.56,107.40,59.26,55.25,5 1.10,46.92,38.51,38.38,36.41,27.92,22.82,20.46,15.11,14.48,8.09.HRMS(ESI-TOF)m / z:[M-PF6 - ] + calcdfor C 49 H 50 FN4O3S2825.3303; found825.3331.

[0068] Example 6

[0069] 0.5mmol 0.5mmol 0.7mmol sodium methoxide and 10mL methanol were reacted at 75℃ and nitrogen atmosphere for 14h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.1MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 80℃ for 2h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 300 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 1:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0070]

[0071] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 42%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 11H NMR (400 MHz, DMSO) δ 15.32 (s, 1H), 8.98 (br, 1H), 8.88 (br, 2H), 8.16 (br, 2H), 7.98 (br, 1H), 7.55 (s, 2H), 7.38 (s, 2H), 7.25 (br, 3H), 7.06 (d, J = 30.1 Hz, 3H), 4.60 (br, 2H), 4.47 (br, 2H), 3.55 (br, 2H), 3.20 (br, 8H), 2.84 (br, 4H), 2.35 (br, 2H), 2.04 (br, 5H), 1.92 (br, 3H), 1.56 (br, 2H), 1.42 (br, 4H), 1.34 (br, 3H). 13 13C NMR (100 MHz, DMSO) δ 176.66, 166.51, 153.20, 149.27, 144.42, 139.92, 139.60, 137.86, 137.60, 137.02, 136.83, 136.28, 136.08, 135.74, 134.49, 134.12, 134.05, 133.76, 133.51, 129.55, 128.74, 127.89, 127.81, 125.28, 124.70, 123.76, 121.37, 107.71, 99.91, 59.94, 55.69, 55.53, 49.62, 38.52, 38.39, 30.77, 25.57, 22.81, 17.90, 17.83, 15.12, 14.90, 14.62, 14.50. HRMS (ESI-TOF) m / z: [M - PF6 - + calcd for C 50 H 54 FN4O3S2 841.3616; found 841.3625.

[0072] Example 7

[0073] Take 0.5 mmol 0.5 mmol ​1mmol sodium ethoxide and 15mL anhydrous ethanol reacted at 80℃ and nitrogen atmosphere for 16h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.3MPa. Then the residue was dissolved in 3mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 75℃ for 2.5h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 300 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 1:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0074]

[0075] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 45%, and the nuclear magnetic resonance and mass spectrometry data are as follows: 1 H NMR(400MHz,DMSO)δ15.16(s,1H),8.86(s,2H),8.70(s,1H),8.16(br,1H),8.0 9(d,J=16.2Hz,1H),7.98(br,1H),7.54(br,2H),7.38(br,2H),7.27(d,J=22.9H z,3H),7.00(d,J=17.0Hz,3H),4.46(br,2H),3.84(br,1H),3.19(br,8H),2.83( br,4H),2.04(br,5H),1.92(br,5H),1.61(br,2H),1.33(br,6H),1.21(br,4H). 13 C NMR (100MHz, DMSO) δ176.88,166.36,153.19,152.17,151.29,148.65,144.43,139.90,139.60,137. 85,137.03,136.83,135.90,135.73,134.47,134.12,134.05,133.77,133.52,129.55,127.80,125.2 8,124.71,124.56,123.76,121.37,111.70,111.49,107.31,60.00,38.52,38.39,36.40,30.80,30. 31,30.00,29.49,29.41,26.39,25.63,25.57,22.81,15.11,14.49,8.08.HRMS(ESI-TOF)m / z:[M-PF6 - ] + Calculate for C 51 H54 FN4O3S2853.3616; found 853.3604.

[0076] Example 8

[0077] 0.5mmol 0.5mmol 0.9mmol piperidine and 15mL anhydrous ethanol reacted at 80℃ and nitrogen atmosphere for 16h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.1MPa. Then the residue was dissolved in 4mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 80℃ for 2h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 300 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 1:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0078]

[0079] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 43%.

[0080] Example 9

[0081] 0.5mmol 0.5mmol 0.9mmol piperidine and 15mL anhydrous ethanol reacted at 80℃ and nitrogen atmosphere for 16h. After the reaction solution was cooled to room temperature, the solvent was removed by decompression. The vacuum degree of decompression was 0.1MPa. Then the residue was dissolved in 4mL methanol, and saturated ammonium hexafluorophosphate aqueous solution was added dropwise. After a large amount of solid precipitated, it was filtered and washed with distilled water 3 times. After that, the solid was dried at 80℃ for 2h and purified by column chromatography. The filler for column chromatography purification was silica gel with a mesh number of 200 mesh, and the eluent was dichloromethane and methanol. The volume ratio of dichloromethane and methanol was 1:1, and a visible light dithiopheneethylene switch type antibacterial agent was obtained.

[0082]

[0083] The yield of the visible light dithienylethylene switchable antibacterial agent prepared in this example is 37%.

[0084] The photochromic properties, light-controlled antibacterial properties and light-controlled antibacterial action mechanism of the visible light dithienylethylene switchable antibacterial agent prepared in Example 1 were studied and analyzed.

[0085] (1) Photochromic properties of the visible light dithienylethylene switchable antibacterial agent of Example 1

[0086] The visible light dithienylethylene switchable antibacterial agent was dissolved in dichloromethane, chloroform and dimethyl sulfoxide respectively to obtain a solution with a concentration of 20 μmol / L. Under the alternating excitation of blue light and near-infrared light, the photochromic properties of the visible light dithienylethylene switchable antibacterial agent were shown in the figure. Figure 1 As shown, (a) is the change of ultraviolet absorption with blue light irradiation, (b) is the change of ultraviolet absorption with near-infrared light irradiation, (c) is the anti-fatigue graph, and (d) is the change of ultraviolet absorption in different solvents; the fluorescence switching performance of the visible light dithienylethylene switch type antibacterial agent is shown in Figure 2 As shown, (a) is a graph showing the change of fluorescence emission with blue light irradiation, (b) is a graph showing the change of fluorescence emission with near-infrared light irradiation, (c) is a graph showing the change of fluorescence emission in different solvents, and (d) is a graph showing the fluorescence attenuation in different solvents. Figure 1 and Figure 2 It can be seen that the visible light dithienylethylene switchable antibacterial agent exhibits excellent photochromic properties in solvents of different polarities, with a fluorescence lifetime of 0.4 to 1.55 ns and a fluorescence quantum yield of 7 to 28%.

[0087] (2) The light-controlled antibacterial performance of the visible light dithienylethylene switchable antibacterial agent of Example 1

[0088] Using the standard microbroth dilution method, the in vitro minimum inhibitory concentrations (Escherichia coli and Staphylococcus aureus) of the positive reference drug norfloxacin and the visible light dithienylethylene switchable antibacterial agent before illumination were determined under the same conditions. The antibacterial agent molecules were then illuminated to achieve photostable state, and the minimum inhibitory concentration at photostable state was determined. The antibacterial agent molecules were then dissolved in dimethyl sulfoxide to obtain a solution with a concentration of 256 μg / mL, and then subjected to a light-controlled antibacterial experiment. The light-controlled antibacterial performance diagram is shown in the figure below. Figure 3 As shown, (a) is the minimum inhibitory concentration of the switch-type antimicrobial agent and norfloxacin before and after illumination, (b) is the growth curve of Escherichia coli under in-situ blue light irradiation of the switch-type antimicrobial agent, and (c) is the growth curve of Escherichia coli under in-situ near-infrared irradiation of the switch-type antimicrobial agent. Figure 3 It can be seen that for Escherichia coli, the in vitro antibacterial activity of the open-ring isomer of the visible light dithienylethylene switchable antibacterial agent is 4 times that of the closed-ring isomer. In addition, in the presence of Escherichia coli, the antibacterial experiment of the visible light dithienylethylene switchable antibacterial agent irradiated by near-infrared light in situ and its in vitro light-controlled antibacterial experiment showed the same experimental results. Therefore, the visible light dithienylethylene switchable antibacterial agent can be activated in situ by near-infrared light for use in the field of photopharmacological antibacterial.

[0089] (3) Causes of the difference in antibacterial activity of the visible light dithienylethylene switchable antibacterial agent before and after irradiation and the mechanism of light-controlled antibacterial action

[0090] According to the experimental results of the in vitro and in vivo antibacterial activity of the visible light dithiopheneethylene switchable antibacterial agent (the in vitro antibacterial activity of the open ring isomer of the visible light dithiopheneethylene switchable antibacterial agent is 4 times that of the closed ring isomer), the molecular docking technology (Docking) was used to calculate the interaction mode between the switch ring isomer of the visible light dithiopheneethylene switchable antibacterial agent and the bacterial DNA helicase (a type IIA topoisomerase) through the Sybyl X software (V2.0). The switch ring isomer of the visible light dithiopheneethylene switchable antibacterial agent was subjected to molecular docking experiments with the bacterial DNA helicase. The molecular docking diagram of the switch ring isomer of the visible light dithiopheneethylene switchable antibacterial agent and the bacterial DNA helicase is shown in the figure. Figure 4 As shown, (a) is the docking diagram of the ring-opening isomer and the DNA helicase molecule (seen from the front), (b) is the docking diagram of the ring-opening isomer and the DNA helicase molecule (seen from the back), (c) is the docking diagram of the ring-closing isomer and the DNA helicase molecule (seen from the front), and (d) is the docking diagram of the ring-closing isomer and the DNA helicase molecule (seen from the back). Figure 4 It can be seen that compared with the closed-ring isomer, the open-ring isomer of norfloxacin can be inserted into the double helix structure of DNA, which is beneficial to cutting DNA and thus inhibiting DNA replication.

[0091] The present invention studies and analyzes the photochromic properties, fluorescent switching properties, causes of differences in antibacterial activity before and after illumination, and light-controlled antibacterial properties of a visible light dithienylethylene switchable antibacterial agent, and finds that under alternating irradiation of blue light and near-infrared light, the visible light dithienylethylene switchable antibacterial agent exhibits excellent light switching properties, and can achieve regulation of the antibacterial activity of Escherichia coli. Specifically, for Escherichia coli, the in vitro antibacterial activity of the open-ring isomer of the visible light dithienylethylene switchable antibacterial agent is four times that of the closed-ring isomer, and the visible light dithienylethylene switchable antibacterial agent can be used as a new switchable antibacterial agent in photopharmacological drugs.

[0092] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A visible light dithienylethylene switchable antibacterial agent, characterized in that: The structural formula of the visible light dithienylethylene switchable antibacterial agent is Wherein, R1 is a chlorine atom, R2 is n is 0, 1 or 2.

2. The method for preparing the visible light dithienylethylene switch type antibacterial agent according to claim 1, characterized in that: The following steps are included: Compound I, compound II, an organic solvent and an organic base are reacted, and the reaction solution is decompressed and purified in sequence to obtain a visible light dithienylethylene switchable antibacterial agent; The structural formula of the compound I is Wherein, R1 is a chlorine atom, The structural formula of the compound II is Among them, R2 is n is 0, 1 or 2.

3. The preparation method according to claim 2, characterized in that: The organic solvent is one or more of N,N-dimethylformamide, acetone, acetonitrile, tetrahydrofuran, 1,4-dioxane, anhydrous ethanol and methanol.

4. The preparation method according to claim 3, characterized in that: The organic base is one or more of triethylamine, pyridine, piperidine, diethylamine, trimethylamine, diisopropylethylamine, n-butylamine, n-propylamine, sodium tert-butoxide, potassium tert-butoxide, sodium methoxide and sodium ethoxide.

5. The preparation method according to claim 3 or 4, characterized in that: The molar volume ratio of the compound I, the compound II, the organic base and the organic solvent is 1 mmol: 1 mmol: 0.2-2 mmol: 20-60 mL.

6. The preparation method according to claim 5, characterized in that: The reaction temperature is 60-80° C., the reaction time is 14-18 hours, and the reaction is carried out under a nitrogen atmosphere.

7. The preparation method according to claim 6, characterized in that: The purification method is column chromatography purification.

8. The preparation method according to claim 7, characterized in that: The filler for column chromatography purification is silica gel, and the mesh number of the silica gel is 200-300 meshes; the eluent for column chromatography purification is dichloromethane and methanol, and the volume ratio of dichloromethane to methanol is 1-20:

1.

9. Use of the visible light dithienylethylene switchable antibacterial agent according to claim 1 in the preparation of light-controlled antibacterial drugs.

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