Amphiphilic eugenol-quaternary phosphonium salt hybrids and uses thereof

Abstract

The application discloses a series of eugenol-quaternary phosphonium salt conjugates and antibacterial application thereof. The series of compounds are obtained by introducing a quaternary phosphonium salt fragment on a phenolic hydroxyl group of eugenol as a leading compound, so that a series of eugenol-quaternary phosphonium salt conjugates are obtained, and the structural general formula is shown in the following formula (I). The series of compounds exhibit excellent antibacterial activity, and the inhibitory activity on common gram-positive bacteria such as staphylococcus aureus and enterococcus faecium and methicillin-resistant staphylococcus aureus is equivalent to that of vancomycin, a glycopeptide antibiotic. Through structural modification, the water solubility and antibacterial activity of eugenol are improved, and the hemolytic toxicity and cytotoxicity are relatively low. Therefore, the eugenol-quaternary phosphonium salt conjugate has the potential to be further developed as a new type of antibacterial drug.

Description

Technical Field

[0001] This invention belongs to the field of medicinal chemistry technology, and in particular relates to amphiphilic eugenol-quaternary phosphine salt hybrids and their applications. Background Technology

[0002] With the widespread use of broad-spectrum antibiotics, bacterial resistance has become an increasingly serious problem. Methicillin-resistant Staphylococcus aureus (MRSA) was first discovered in hospitalized patients in the 1960s (New England Journal of Medicine, 1968, 279, 441). MRSA can cause highly fatal fulminant invasive diseases such as pneumonia, osteomyelitis, and sepsis, exhibiting extremely high virulence and drug resistance (Nature Reviews Microbiology, 2009, 7, 629). Therefore, the development of novel antibiotics to combat MRSA infections has become an urgent need.

[0003] Eugenol, a natural product, possesses a variety of biological activities, including antioxidant, analgesic, antiplatelet, anti-allergic, and antibacterial effects, demonstrating broad pharmacological potential (International Journal of Food Properties, 2016, 19, 2156; Bioorganic Chemistry, 2019, 88, 102931). However, due to its poor water solubility and limited antibacterial activity, it is necessary to modify and refine its structure to further enhance its antibacterial efficacy and improve its drug-like properties. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an amphiphilic eugenol-quaternary phosphine salt hybrid and its applications. The amphiphilic eugenol-quaternary phosphine salt hybrid exhibits excellent inhibitory activity against Gram-positive bacteria such as Staphylococcus aureus and MRSA, and solves the problem of poor water solubility.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: In a first aspect, the present invention provides a compound having the structure described in general formula I: , in: R 1 Selected from C 1-6 Alkyl, phenyl, heteroaryl, fused cycloalkyl, heterofused cycloyl, 3-6 membered saturated cycloalkyl, 3-6 membered saturated heterocyclic; R 2 Selected from C 1-6 Alkyl, phenyl, heteroaryl, fused cycloalkyl, heterofused cycloyl, 3-6 membered saturated cycloalkyl, 3-6 membered saturated heterocyclic group; R 3 Selected from hydroxyl, amino, amide, guanidinyl, thiol, halogen, C 1-6 Alkyl, halogen-substituted C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 alkylamine group, C 1-6 Alkylthio, phenyl; R 4 Selected from hydrogen, hydroxyl, amino, amide, guanidinyl, mercapto, halogen, C 1-6 Alkyl, halogen-substituted C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 alkylamine group, C 1-6 Alkylthio, phenyl; R 5 Selected from hydrogen, hydroxyl, amino, amide, guanidinyl, mercapto, halogen, C 1-6 Alkyl, halogen-substituted C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 alkylamine group, C 1-6 Alkylthio, phenyl; n is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8; X is selected from fluorine, chlorine, bromine, iodine, trifluoroacetate, sulfate, hydrochloric acid, nitric acid, acetic acid, and formic acid.

[0006] Preferably, the eugenol-quaternary phosphine salt compound is selected from: , The solvates or deuterated compounds of the above compounds.

[0007] A pharmaceutical composition comprising the above-described compound or a solvate or deuterated compound thereof, and pharmaceutically acceptable excipients.

[0008] According to conventional methods, the pharmaceutical composition can be formulated into dosage forms such as powders, granules, tablets, capsules, suspensions, emulsions, syrups, sprays, etc., for oral administration, external use, suppositories, and sterile injectable solutions. The non-pharmaceutical active ingredients, such as carriers, excipients, and diluents that may be included, are well known in the art, and those skilled in the art can determine that they meet clinical standards.

[0009] Use of the above-mentioned compounds or their pharmaceutically acceptable salts or solvates or deuterated compounds in the preparation of antibacterial drugs.

[0010] The bacteria include Escherichia coli, Staphylococcus aureus, Bacillus thuringiensis, Bacillus subtilis, and Enterococcus faecalis.

[0011] It is evident that the above-described pharmaceutical compositions or formulations can be used to treat bacterial-related diseases.

[0012] In another aspect, the present invention provides an antibacterial method comprising administering to a subject a therapeutically effective amount of the aforementioned compound, pharmaceutical composition, or pharmaceutical preparation.

[0013] The beneficial technical effects of this invention are as follows: This invention provides an eugenol quaternary phosphine salt compound, which exhibits anti-proliferative activity against Gram-positive bacteria such as Staphylococcus aureus and Enterococcus faecalis. Through antibacterial tests, we found that the compound showed good efficacy against Gram-positive bacteria and methicillin-resistant Staphylococcus aureus, comparable to the positive control drug vancomycin, while its effect on Gram-negative bacteria such as Escherichia coli was generally weak. Furthermore, in the bactericidal kinetics test, we clearly observed that the antibacterial activity of the compound exhibited significant solubility and time dependence. Therefore, these results indicate that the eugenol quaternary phosphine salt compound provided by this invention is an antibacterial agent with good antibacterial activity and warrants further investigation.

[0014] Regarding the definition of terms used in this invention: Unless otherwise stated, the initial definitions provided for groups or terms herein apply to the groups or terms used throughout this specification; for terms not specifically defined herein, the meanings that a person skilled in the art would give them should be given based on the disclosure and context.

[0015] The minimum and maximum carbon atom content in hydrocarbon groups are indicated by a prefix, for example, the prefix C. a~b Alkyl groups refer to any alkyl group containing one to two carbon atoms. For example, C 1~6 Alkyl refers to a straight-chain or branched alkyl group containing 1 to 6 carbon atoms. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl and their various branched isomers.

[0016] "Alkoxy" refers to -O- (alkyl), where alkyl is defined as described above. Non-limiting examples of alkoxy groups include: methoxy, ethoxy, propoxy, and butoxy. Alkoxy groups can be optionally substituted or unsubstituted.

[0017] "Cycloalkyl" refers to a saturated or partially unsaturated monocyclic or polycyclic cyclic hydrocarbon substituent, wherein the cycloalkyl ring contains 3 to 20 carbon atoms, preferably 3 to 6 carbon atoms. Non-limiting examples of monocyclic cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cyclohexadienyl, etc.; polycyclic cycloalkyl groups include spirocyclic, fused, and bridged cycloalkyl groups. Cycloalkyl groups can be substituted or unsubstituted; when substituted, the substituent can be replaced at any usable connection point, preferably one or more of the following groups, independently selected from halogens, hydroxyl groups, oxo groups, cyano groups, amino groups, C6 groups, etc. 1-6 Alkyl, C 1-6 Alkoxy, 3- to 6-membered cycloalkyl, or 3- to 6-membered heterocycloalkyl, wherein the alkyl, alkoxy, cycloalkyl, or heterocycloalkyl may optionally be substituted with halogen, hydroxyl, nitro, cyano, or amino.

[0018] "Heterocycloalkyl" refers to a saturated or partially unsaturated monocyclic or polycyclic cyclic hydrocarbon substituent containing 3 to 20 ring atoms, one or more of which are selected from nitrogen, oxygen, or S(O). m (where m is an integer from 0 to 2) heteroatoms, but excluding the -OO-, -OS-, or -SS- ring portions, with the remaining ring atoms being carbon. Preferably, it contains 3 to 12 ring atoms, of which 1 to 4 are heteroatoms; more preferably, it contains 3 to 7 ring atoms. Non-limiting examples of "heterocyclic alkyl" include: , , wait.

[0019] The heterocyclic alkyl ring may be fused to an aryl or heteroaryl ring, wherein the ring attached to the parent structure is a heterocyclic alkyl ring, and non-limiting examples include: and wait.

[0020] Heterocyclic alkyl groups may be optionally substituted or unsubstituted. When substituted, the substituents are preferably one or more of the following groups, independently selected from halogens, hydroxyl groups, oxo groups, cyano groups, amino groups, and C4 groups. 1-6 Alkyl, C 1-6 Alkoxy, 3- to 6-membered cycloalkyl, or 3- to 6-membered heterocycloalkyl, wherein the alkyl, alkoxy, cycloalkyl, or heterocycloalkyl may optionally be substituted with halogen, hydroxyl, nitro, cyano, or amino.

[0021] "Aryl" refers to a 6- to 14-membered all-carbon monocyclic or fused polycyclic (i.e., a ring sharing adjacent carbon atom pairs) group having a conjugated π-electron system, preferably 6- to 12-membered, such as phenyl and naphthyl. The aryl ring may be fused to a heteroaryl, heterocycloalkyl, or cycloalkyl ring, wherein the ring connected to the parent structure is an aryl ring, and non-limiting examples include: , and .

[0022] The aryl group can be substituted or unsubstituted. When substituted, the substituent is preferably one or more of the following groups, independently selected from halogen, hydroxyl, oxo, nitro, cyano, C 1-6 Alkyl, C 1-6 Alkoxy, C 2-6 alkenyloxy group, C 2-6 Alkyne group, 3- to 6-membered cycloalkoxy group, 3- to 6-membered heterocycloalkoxy group, C 3-8 Cycloalkenyloxy, 5- to 6-membered aryl or heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Alkoxy, C 2-6 alkenyloxy group, C 2-6 The alkynyl group, 3 to 6 cycloalkoxy group, 3 to 6 heterocycloalkoxy group, 3 to 8 cycloalkenyl group, 5 to 6 aryl group, or heteroaryl group may be selected from one or more halogens, hydroxyl groups, cyano groups, amino groups, C6 groups, etc. 1-6 Alkyl or C 1-6 Alkyl-substituted.

[0023] "Heteroaryl" refers to a heteroaryl system comprising 1 to 4 heteroatoms and 5 to 14 ring atoms, wherein the heteroatoms are selected from oxygen, sulfur, and nitrogen. The heteroaryl group is preferably 6 to 12-membered, more preferably 5-membered or 6-membered. For example, non-limiting examples include: imidazolyl, furanyl, thiophene, thiazolyl, pyrazolyl, oxazolyl, isoxazolyl, pyrrole, tetrazolyl, pyridinyl, pyrimidinyl, thiadiazole, pyrazinyl, triazolyl, indazole, benzimidazolyl, etc. , , wait.

[0024] The heteroaryl ring may be fused to an aryl, heterocyclic alkyl, or cycloalkyl ring, wherein the ring connected to the parent structure is a heteroaryl ring, and non-limiting examples include: , and .

[0025] The heteroaryl group can be optionally substituted or unsubstituted. When substituted, the substituent is preferably one or more of the following groups, independently selected from halogens, hydroxyl groups, cyano groups, amino groups, C4 groups, etc. 1-6 Alkyl or C 1-6 Alkyl group.

[0026] "Halogen" refers to fluorine, chlorine, bromine, or iodine.

[0027] The term “independently” or “each independently” as used in this article means that, within a compound, the same or different values ​​can be chosen for a variable given in multiple instances.

[0028] Obviously, based on the above description of the present invention, and according to common technical knowledge and effective means in the field, various other modifications, substitutions or alterations can be made without departing from the basic technical concept of the present invention. Attached Figure Description

[0029] Figure 1 The inhibition zone experiment of the preferred target compound and positive control against Staphylococcus aureus is presented in this invention.

[0030] Figure 2 The inhibition zone experiment of the preferred target compound and positive control against Bacillus thuringiensis in this invention.

[0031] Figure 3 The inhibition zone experiment of the preferred target compound and positive control against Bacillus subtilis is presented in this invention.

[0032] Figure 4 The inhibition zone experiment of the preferred target compound and positive control against Enterococcus faecalis in this invention. Detailed Implementation

[0033] The following detailed embodiments further illustrate the above-described content of the present invention. However, this should not be construed as limiting the scope of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention.

[0034] The following embodiments better illustrate the content of the present invention. However, the present invention is not limited to the following embodiments.

[0035] Example 1 Preparation of intermediate compound 4g , 970 mg of 5 mmol of 4-allylphenol (5) and 15 mmol of 1,6-dibromohexane (3e) were dissolved in 10 mL of acetonitrile (99.9 vol%), and 2.07 g of 15 mmol of anhydrous potassium carbonate was added. The reaction mixture was refluxed at 80 °C. Thin-layer chromatography was monitored until the reaction was complete, and then the mixture was concentrated under reduced pressure. The residue was dissolved in 25 mL of ethyl acetate (99.5 vol%), washed successively with saturated ammonium chloride aqueous solution and saturated brine, and the organic layer was collected, dried over anhydrous sodium sulfate, filtered, and concentrated to give the crude product. Finally, the crude product was purified by silica gel column chromatography to give 1.1 g of compound (4 g), with a yield of 74.3%. Petroleum ether:ethyl acetate = 20:1 (v / v) was used as the eluent for the silica gel column.

[0036] The nuclear magnetic resonance (NMR) spectroscopy data of compound 4g are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.12 – 7.08 (m, 2H), 6.85 – 6.82 (m,2H), 5.99 – 5.92 (m, 1H), 5.08 – 5.03 (m, 2H), 3.96 – 3.92 (m, 2H), 3.44 –3.41 (m, 2H), 3.33 (d, J = 6.8 Hz, 2H), 1.92 – 1.88 (m, 2H), 1.81 – 1.77 (m, 2H), 1.57 – 1.49 (m, 4H). 13 C NMR (100 MHz, DMSO- d 6) δ 157.43, 137.90, 132.00, 129.46, 115.36,114.45, 67.73, 39.33, 33.77, 32.69, 29.13, 27.92, 25.31.

[0037] Example 2 Preparation of intermediate compound 4h , 388 mg and 2 mmol of 4-allyl-2,6-dimethoxyphenol (compound 6) and 6 mmol of 1,6-dibromohexane (compound 3e) were dissolved in 4 mL of acetonitrile. 828 mg and 6 mmol of anhydrous potassium carbonate were added, and the reaction mixture was refluxed at 80 °C. Thin-layer chromatography was monitored until the reaction was complete, then the mixture was concentrated under reduced pressure. The residue was dissolved in 20 mL of ethyl acetate and washed successively with saturated ammonium chloride aqueous solution and saturated brine. The organic layer was collected, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 572 mg of compound 4 h, with a yield of 80.3%. Petroleum ether:ethyl acetate = 20:1 (v / v) was used as the eluent for the silica gel column.

[0038] The nuclear magnetic resonance (NMR) spectra of compound 4h are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 6.40 (s, 2H), 6.00 – 5.93 (m, 1H), 5.14 – 5.07 (m, 2H), 3.96 – 3.92 (m, 2H), 3.82 (s, 6H), 3.44 – 3.40 (m, 2H), 3.35 – 3.32 (m, 2H), 1.90 – 1.87 (m, 2H), 1.77 – 1.73 (m, 2H), 1.52 – 1.48 (m, 4H). 13 C NMR (100 MHz, Chloroform- d ) δ 153.35, 137.23, 135.51, 115.92, 105.53, 73.09, 56.06, 40.49, 33.91, 32.78, 29.84, 27.93, 25.06.

[0039] Example 3 Preparation of compound 1a , 149 mg of 0.5 mmol intermediate 4c and 184 μL of 0.75 mmol tributylphosphine (i.e., compound 7a) were dissolved in 1 mL of acetonitrile, and the reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to give 143 mg of compound 1a, with a yield of 57.17%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column.

[0040] The nuclear magnetic resonance (NMR) spectroscopy data of compound 1a are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 6.78 (d, J = 7.6 Hz, 1H), 6.70 – 6.67(m, 2H), 5.94 – 5.87 (m, 1H), 5.06 – 5.01 (m, 2H), 4.03 (t, J = 5.6 Hz, 2H),3.79 (s, 3H), 3.29 (d, J = 6.8 Hz, 2H), 2.63 – 2.55 (m, 2H), 2.45 – 2.37 (m,6H), 2.03 – 1.96 (m, 2H), 1.84 – 1.78 (m, 2H), 1.53 – 1.46 (m, 12H), 0.91 (t, J = 6.8 Hz, 9H). 13 C NMR (150 MHz, Chloroform- d ) δ 149.12, 146.17, 137.41, 133.28,120.60, 115.57, 113.40, 112.22, 67.80, 55.68, 39.66, 29.62, 29.52, 23.91,23.81, 23.69, 23.66, 19.18, 19.01,18.92, 18.89, 18.86, 18.69, 13.34.

[0041] Example 4 Preparation of compound 1b , 149 mg, 0.5 mmol intermediate 4c and 210 mg, 0.75 mmol tricyclohexylphosphine (i.e., compound 7b) were dissolved in 1 mL acetonitrile, and the reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. The crude product was finally purified by silica gel column chromatography to obtain 153 mg of compound 1b, with a yield of 52.9%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column.

[0042] The nuclear magnetic resonance (NMR) spectroscopy data of compound 1b are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 6.80 (d, J = 8.0 Hz, 1H), 6.70 – 6.66(m, 2H), 5.96 – 5.85 (m, 1H), 5.06 – 5.01 (m, 2H), 4.07 (t, J = 5.6 Hz, 2H), 3.78 (s, 3H), 3.29 (d, J = 6.8 Hz, 2H), 2.64 – 2.51 (m, 5H), 2.09 – 2.04 (m,2H), 2.00 – 1.96 (m, 6H), 1.90 – 1.85 (m, 8H), 1.78 (d, J = 12.8 Hz, 2H) 1.55 –1.36 (m, 12H), 1.29 – 1.22 (m, 4H). 13 C NMR (150 MHz, Chloroform- d ) δ 149.01, 146.21, 137.46, 133.01,120.59, 115.52, 113.15, 112.13, 67.31, 55.69, 39.65, 30.00, 29.82, 29.73,27.11, 27.08, 26.43, 26.35, 25.30,25.29, 19.61, 19.58, 15.38, 15.10.

[0043] Example 5 Preparation of compound 1c , 149 mg of 0.5 mmol intermediate 4c and 107 μL of 0.75 mmol dimethylphenylphosphine (i.e., compound 7c) were dissolved in 1 mL of acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 106 mg of compound 1c, with a yield of 48.6%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column chromatography.

[0044] The nuclear magnetic resonance (NMR) spectral data of compound 1c are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.95 – 7.90 (m, 2H), 7.66 – 7.56 (m,3H), 6.74 (d, J = 8.4 Hz, 1H), 6.66 – 6.64 (m, 2H), 5.95 – 5.84 (m, 1H), 5.05 –5.00 (m, 2H), 3.95 (t, J = 5.6 Hz, 2H), 3.72 (s, 3H), 3.27 (d, J = 6.8 Hz, 2H), 3.11 – 3.03 (m, 2H), 2.54 (s, 3H), 2.51 (s, 3H), 1.96 – 1.89 (m, 2H), 1.75 –1.68 (m, 2H). 13 C NMR (150 MHz, Chloroform- d ) δ 149.13, 146.22, 137.43, 134.18,134.16, 133.16, 131.34, 131.27, 130.03, 129.95, 120.56, 115.53, 113.60,112.26, 68.02, 55.68, 39.64, 29.35, 29.24, 23.23, 22.89, 18.82, 18.79, 8.68,8.32.

[0045] Example 6 Preparation of compound 1d , 149 mg of 0.5 mmol intermediate 4c and 140 μL of 0.75 mmol diphenylmethylphosphine (i.e., compound 7e) were dissolved in 1 mL of acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 128 mg of compound 1d, with a yield of 51.4%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column chromatography.

[0046] The nuclear magnetic resonance (NMR) spectra of compound 1d are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.89 – 7.84 (m, 4H), 7.70 – 7.66 (m,2H), 7.60 – 7.55 (m, 4H), 6.74 (d, J = 7.6 Hz, 1H), 6.66 – 6.63 (m, 2H), 5.94 –5.84 (m, 1H), 5.04 – 4.99 (m, 2H), 3.98 (t, J = 5.6 Hz, 2H), 3.64 (s, 3H), 3.49– 3.40 (m, 2H), 3.27 (d, J = 6.8 Hz, 2H), 2.80 (d, J = 13.6 Hz, 3H), 2.06 – 2.00 (m, 2H), 1.83 – 1.77 (m, 2H). 13 C NMR (150 MHz, Chloroform- d ) δ 148.99, 146.22, 137.39, 134.49,134.47, 133.07, 132.41, 132.35, 130.13, 130.05, 120.58, 119.62, 119.06,115.50, 113.40, 112.19, 68.10, 55.57, 39.60, 28.98, 28.88, 22.48, 22.14,19.36, 19.33, 8.32, 7.96.

[0047] Example 7 Preparation of compound 1e , 162 mg, 0.6 mmol intermediate 4a and 236 mg, 0.9 mmol triphenylphosphine (i.e., compound 7d) were dissolved in 1.2 mL acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 134 mg of compound 1e, with a yield of 41.9%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column.

[0048] The nuclear magnetic resonance (NMR) spectral data of compound 1e are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.86 – 7.79 (m, 9H), 7.74 – 7.70 (m,6H), 6.57 – 6.55 (m, 3H), 5.91 – 5.84 (m, 1H), 5.04 – 4.99 (m, 2H), 3.84 (s,3H), 3.80 – 3.73 (m, 2H), 3.23 (d, J = 6.8 Hz, 2H), 2.99 – 2.93 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 147.38, 141.97, 137.66, 135.15,135.12, 133.68, 133.59, 132.01, 130.61, 130.48, 124.05, 121.79,118.41,117.56, 115.56, 110.79, 56.19, 39.76, 23.98, 23.15, 22.67.

[0049] Example 8 Preparation of compound 1f , 166 mg, 0.58 mmol intermediate 4b and 227 mg, 0.87 mmol triphenylphosphine (i.e., compound 7d) were dissolved in 1.2 mL acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 248 mg of compound 1f, with a yield of 78.3%. The silica gel column used dichloromethane:methanol = 20:1 (v / v) as the eluent.

[0050] The nuclear magnetic resonance (NMR) spectroscopy data of compound 1f are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.88 – 7.83 (m, 6H), 7.78 – 7.74 (m,3H), 7.69 – 7.66 (m, 6H), 6.85 (dd, J = 8.0, 2.8 Hz, 1H), 6.67 – 6.65 (m, 2H), 5.96 – 5.86 (m, 1H), 5.06 – 5.01 (m, 2H), 4.31 – 4.28 (m, 2H), 4.09 – 4.02(m, 2H), 3.78 (s, 3H), 3.29 (d, J = 5.6 Hz, 2H), 2.25 – 2.18 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 148.99, 145.90, 137.56, 134.93,134.90, 133.76, 133.67, 133.29, 130.44, 130.32, 120.80, 118.67,117.82,115.56, 113.99, 112.02, 67.82, 67.65, 55.73, 39.73, 23.09, 19.75, 19.23.

[0051] Example 9 Preparation of 1g of compound , 178 mg, 0.6 mmol intermediate 4c and 236 mg, 0.9 mmol triphenylphosphine (i.e., compound 7d) were dissolved in 1.2 mL acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 1 g of compound 192 mg, with a yield of 57.13%. The silica gel column used dichloromethane:methanol = 20:1 (v / v) as the eluent.

[0052] The nuclear magnetic resonance (NMR) spectra of 1g of compound are as follows: 1 H NMR (400 MHz, Chloroform-d ) δ 7.83 – 7.74 (m, 9H), 7.67 – 7.63 (m,9H), 6.78 – 6.76 (m, 1H), 6.70 – 6.64 (m, 2H), 5.95 – 5.89 (m, 1H), 5.08 –5.02 (m, 2H), 4.07 – 4.05 (m, 2H), 3.98 – 3.91 (m, 2H), 3.62 (s, 3H), 3.30(d, J = 6.4 Hz, 2H), 2.22 – 2.18 (m, 2H), 1.96 – 1.85 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 149.05, 146.40, 137.54, 134.91,133.71, 133.68, 133.61, 133.58, 133.07, 130.45, 130.33, 120.76, 118.75,118.71, 117.86, 115.60, 113.44, 113.41, 112.29, 68.12, 55.65, 39.72, 29.08,28.92,22.36, 21.86, 19.87.

[0053] Example 10 Preparation of compound 1h , 187 mg, 0.6 mmol intermediate 4f and 236 mg, 0.9 mmol triphenylphosphine (i.e., compound 7d) were dissolved in 1.2 mL of acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 149 mg of compound 1 h, with a yield of 43.26%. The silica gel column used dichloromethane:methanol = 20:1 (v / v) as the eluent.

[0054] The nuclear magnetic resonance (NMR) spectra of compound 1 h are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.83 – 7.73 (m, 9H), 7.68 – 7.63 (m, 6H), 6.72 (d, J= 8.0 Hz, 1H), 6.67 – 6.64 (m, 2H), 5.95 – 5.87 (m, 1H), 5.07 –5.1 (m, 2H), 3.92 – 3.89 (m, 2H), 3.83 – 3.77 (m, 2H), 3.71 (s, 3H), 3.29 (d, J = 6.8 Hz, 2H), 1.84 – 1.82 (m, 4H), 1.72 – 1.68 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 149.17, 146.57, 137.59, 134.93,134.91, 133.65, 133.55, 132.83,130.47, 130.34, 120.54, 118.70, 117.84,115.51,113.47, 112.25, 68.63, 55.79, 39.71, 28.52, 27.08, 26.92, 22.88,22.38, 22.34, 22.29.

[0055] Example 11 Preparation of compound 1i , 196 mg (0.6 mmol) of 4 g of intermediate and 236 mg (0.9 mmol) of triphenylphosphine (i.e., compound 7d) were dissolved in 1.2 mL of acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 194 mg of compound 1i, with a yield of 54.97%. The silica gel column used dichloromethane:methanol = 20:1 (v / v) as the eluent.

[0056] The nuclear magnetic resonance (NMR) spectral data of compound 1i are as follows: 1 H NMR (400 MHz, Chloroform- d) δ 7.86 – 7.76 (m, 9H), 7.70 – 7.67 (m,6H), 6.77 – 6.75 (m, 1H), 6.69 – 6.66 (m, 2H), 5.98 – 5.88 (m, 1H), 5.08 –5.02 (m, 2H), 3.93 – 3.90 (m, 2H), 3.85 – 3.79 (m, 2H), 3.77 (s, 3H), 3.29(d, J = 6.8 Hz, 2H), 1.75 – 1.63 (m, 6H), 1.50 – 1.42 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 149.18, 146.71, 137.63, 134.93,134.90, 133.70, 133.60, 132.70, 130.49, 130.37, 120.52, 118.79, 117.92,115.51, 113.29, 112.27, 68.82, 55.86, 39.73, 30.02,29.86, 28.70, 25.50,22.88, 22.48, 22.44, 22.38.

[0057] Example 12 Preparation of compound 1j , 354 mg of 1 mmol intermediate (4 g) and 293 mg of 1.5 mmol of triphenylphosphine (i.e., compound 7d) were dissolved in 2 mL of acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 430 mg of compound 1j, with a yield of 69.78%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column chromatography.

[0058] The nuclear magnetic resonance (NMR) spectral data of compound 1j are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.83 – 7.75 (m, 9H), 7.70 – 7.66 (m, 2H), 6.76 (d, J= 8.8 Hz, 1H), 6.68 – 6.66 (m, 2H), 5.97 – 5.87 (m, 1H), 5.06 –5.01 (m, 1H), 3.90 (t, J = 6.8 Hz, 2H), 3.80 (s, 3H), 3.73 – 3.71 (m, 2H), 3.29(d, J = 6.8 Hz, 2H), 1.76 – 1.69 (m, 2H), 1.62 – 1.59 (m, 4H), 1.37 – 1.23 (m, 6H). 13 C NMR (100 MHz, Chloroform- d ) δ 149.17, 146.72, 137.58, 134.95,134.92, 133.58, 133.48, 132.55, 130.47, 130.35, 120.37, 118.65, 117.79,115.44, 113.08, 112.23, 68.94, 55.84, 39.66, 30.25, 30.09, 28.99, 28.91, 28.77, 25.67, 22.86, 22.51, 22.46, 22.37.

[0059] Example 13 Preparation of compound 1k , 139 mg, 0.5 mmol intermediate 5 and 197 mg, 0.75 mmol triphenylphosphine (i.e., compound 7d) were dissolved in 1 mL acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 205 mg of compound 1k, with a yield of 73.45%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column.

[0060] The nuclear magnetic resonance (NMR) spectroscopy data for compound 1k are as follows: 1 H NMR (400 MHz, Chloroform- d) δ 7.85 – 7.75 (m, 9H), 7.70 – 7.65 (m,6H), 7.04 – 7.02 (m, 2H), 6.75 – 6.73 (m, 2H), 5.94 – 5.86 (m, 1H), 5.03 –4.98 (m, 2H), 3.86 – 3.77 (m, 4H), 3.29 – 3.26 (m, 2H), 1.72 – 1.64 (m, 6H), 1.46 – 1.43 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 153.26,137.79, 134.95, 133.63,133.53, 131.82, 130.49, 130.36, 129.35, 118.67, 117.82, 115.27, 114.31,67.54, 39.22, 30.02, 29.86, 28.75, 25.59, 22.86, 22.50,22.36.

[0061] Example 14 Preparation of compound 1l , 134 mg, 0.4 mmol intermediate 6 and 157 mg, 0.6 mmol triphenylphosphine (i.e., compound 7d) were dissolved in 0.8 mL acetonitrile. The reaction mixture was stirred and refluxed at 110 °C. Thin-layer chromatography was monitored until the reaction was complete, followed by concentration under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to obtain 153 mg of compound 1l, with a yield of 61.87%. Dichloromethane:methanol = 20:1 (v / v) was used as the eluent for the silica gel column chromatography.

[0062] The nuclear magnetic resonance (NMR) spectroscopy data of compound 1l are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.81 – 7.74 (m, 9H), 7.68 – 7.64 (m,6H), 6.33 (s, 2H), 5.95 – 5.85 (m, 1H), 5.08 – 5.02 (m, 2H), 3.83 – 3.80 (m,2H), 3.75 – 3.68 (m, 8H), 3.27 (d, J= 6.8 Hz, 2H), 1.68 – 1.60 (m, 6H), 1.45 –1.43 (m, 2H). 13 C NMR (100 MHz, Chloroform- d ) δ 153.13, 137.08, 135.49, 135.20,134.93, 134.90, 133.57, 133.47, 130.45, 130.33, 118.61, 118.59, 117.76,117.74, 115.85, 105.32, 72.98,55.94, 40.37, 30.05, 29.89, 29.35, 25.30,22.87, 22.38, 22.34.

[0063] The following experimental examples demonstrate the beneficial effects of the compounds of this invention.

[0064] Experimental Example 1: Antibacterial Zone Experiment of the Compound of the Invention The inhibition zone was determined using the perforated diffusion method. The concentration of the test strain was first diluted to 1×10⁻⁶ with culture medium. 5 For each CFU / mL bacterial culture, 100 μL of the bacterial suspension was evenly spread onto the surface of a broth agar plate. The plate was allowed to stand for 5 minutes to allow the bacteria to absorb the suspension, and then wells were punched. A basal stock solution of 25000 μg / mL was prepared using sterile water. Before use, the stock solution was diluted to 250 μg / mL with culture medium. 50 μL of the solution was added to each well, and the plate was allowed to stand for 30 minutes to allow diffusion. The plate was then inverted and incubated at 37°C for 16-18 hours. The diameter of the transparent inhibition zone around each well was measured with calipers, accurate to 0.1 mm. Vancomycin (125 μg / mL) was used as a standard reference. Plates containing only culture medium (negative control) and plates inoculated only with the bacterial suspension (positive control) were also prepared to verify the reliability of the experimental system. Each test compound was tested in triplicate, with three replicates. Experiments showed that compounds 1e, 1f, 1g, 1h, and 1i all had certain inhibitory effects on Staphylococcus aureus, Enterococcus faecalis, Bacillus thuringiensis, and Bacillus subtilis, with compounds 1h and 1i exhibiting the best antibacterial activity.

[0065] Experimental Example 2: Determination of the minimum inhibitory concentration of the compound of the present invention The minimum inhibitory concentration (MIC) of the compound was determined by the microbroth dilution method, and the experimental procedure strictly followed the CLSI guidelines. The test strain concentration was diluted with culture medium to 1 × 10⁻⁶. 5The test compound was prepared as a basal stock solution using sterile water at a concentration of CFU / mL, and then diluted to 80 μg / mL with culture medium before use. The 80 μg / mL concentration of the test compound was then serially diluted in sterile centrifuge tubes (80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL, 0.625 μg / mL). Then, 90 μL of culture medium, 10 μL of bacterial suspension, and 100 μL of the serially diluted drug solution were added to each well of a 96-well plate sequentially. The plates were incubated at 37°C for 16-18 hours, and the results were recorded. Vancomycin was used as the standard reference drug in this experiment, and blank and negative controls were also included to ensure data reliability. Each test compound was tested in triplicate, with three replicates. Experimental results showed that compounds 1e, 1i, and 1k had the greatest inhibitory effect on Staphylococcus aureus, with MICs of 1.25 μg / mL, 1.25 μg / mL, and 0.625 μg / mL, respectively.

[0066] Experimental Example 3: Determination of the time-bactericidal dynamic curve of the compound of the present invention The dynamic bactericidal activity of the dominant compound was evaluated using the time-bactericidal curve method. Staphylococcus aureus was inoculated into broth (NB) medium and cultured at 37°C with shaking at 120 rpm until the logarithmic growth phase (1 × 10⁻⁶). 5 CFU / mL). Test compounds at concentrations of 4 × MIC and 8 × MIC were added, with vancomycin at 8 × MIC as a positive control and pure bacterial culture as a negative control. At specific time points (0h, 1h, 2h, 4h, 8h, 12h, 24h), 100 μL of sample was taken from the mixed culture medium and serially diluted 10-fold with physiological saline. Then, 100 μL of the diluted sample was plated onto BA plates. The plates were incubated at 37℃ for 16-18 hours, and the colony count (CFU / mL) was recorded on plates with a count between 30-300. Each sample was tested in triplicate, with three replicates. The method for calculating viable cell count is as follows: Viable bacteria count (CFU / mL) = Average colony count × Dilution factor × 10 (0.1 mL of sample dilution solution is used for plating) Experimental results showed that when the concentration of compound 1i was 10 μg / mL (8×MIC), compound 1i could kill Staphylococcus aureus within 8 hours, while the positive control vancomycin (8×MIC) could not completely kill the bacteria within 8 hours, and the bactericidal effect was lower than or equivalent to the bactericidal effect of compound 1i at the concentration of 8×MIC.

[0067] Experimental Example 4: Hemolytic Toxicity Test of the Compounds of the Invention Hemolytic activity was assessed using sterile human blood, with results expressed as HC. 50 This indicates the concentration of the compound that causes hemolysis in 50% of red blood cells. A 5% red blood cell suspension was prepared using sterile human red blood cells in PBS (1:19, v / v). The test compound was dissolved in PBS to prepare a basal stock solution of a specific concentration. The test compound was then serially diluted with PBS in sterile centrifuge tubes (25600 μg / mL, 12800 μg / mL, 6400 μg / mL, 3200 μg / mL, 1600 μg / mL, 800 μg / mL, 400 μg / mL, 200 μg / mL) for later use. Then, 450 μL of PBS, 25 μL of red blood cell suspension, and 25 μL of the serially diluted test solution were added sequentially to a new EP tube. The mixture was incubated at 37°C for 1 hour. After centrifugation at 4℃ and 2000 rpm for 5 minutes, 200 μL of the supernatant was added to a 96-well plate, and the absorbance (OD) of the supernatant at 540 nm was measured using a UV-Vis spectrophotometer. 540 This experiment included PBS as a negative control and 1% Triton X-100 as a positive control to ensure data reliability. The hemolysis rate was calculated as follows: Hemolysis rate (%) = (OD sample – OD negative control) / (OD positive control – OD negative control) × 100%.

[0068] The selectivity index (SI) is determined by HC. 50 It is determined by dividing by the MIC value (μg / mL) of Staphylococcus aureus.

[0069] Experimental results show that compound 1i has low hemolytic activity (HC). 50 >1280 μg / mL) and good membrane selectivity (SI>1024).

[0070] Experimental Example 5: Cytotoxicity Experiment of the Compound of the Invention The cytotoxicity of the compound against RAW264.7 macrophages was assessed using the CCK-8 assay, and results are expressed as cell viability (%). RAW264.7 cells in logarithmic growth phase were prepared into 1×10⁶ cells using DMEM medium containing 10% FBS. 5Cell suspension was prepared at a concentration of 100 μL / mL. The test compound 1i was dissolved in serum-free DMEM to prepare a basal stock solution of a specific concentration. The test compound was then serially diluted with serum-free DMEM in sterile centrifuge tubes to (16 μM, 32 μM, 64 μM, 128 μM, 256 μM, 512 μM) for later use. In 96-well plates, 100 μL of cell suspension was added to each well, with an equal volume of sterile PBS added to the edge wells to eliminate edge effects. The 96-well plates were incubated at 37°C with 5% CO2 for 24 h until cells adhered and covered approximately 80% of the well bottom. The old culture medium was discarded, and the cells were gently washed 1-2 times with pre-warmed sterile PBS, discarding all PBS. 100 μL of the serially diluted test solution was added to each well, with three replicates for each concentration. A blank control group (serum-free DMEM only) and a negative control group (cells added, but no drug added) were also set up. The plates were returned to the incubator and incubated for another 24 h. After culture, discard the old drug-containing culture medium, gently wash the cells 1-2 times with pre-warmed sterile PBS, and discard the PBS; add 100 μL of a mixture of 10 μL CCK-8 reagent and 90 μL serum-free DMEN to each well, gently tap the plate wall to mix, avoiding the formation of air bubbles; incubate at 37℃ and 5% CO2 for 1-2 h, and measure the absorbance (OD) of each well at 450 nm using a microplate reader. 450 ).

[0071] Cell viability is calculated as follows: Cell viability (%) = (OD sample – OD blank control) / (OD negative control – OD blank control) × 100% Experimental results showed that compound 1i had low cytotoxicity to macrophages (RAW264.7), and the survival rate of macrophages was still as high as 84.67% when the drug concentration was 128 μmol / L.

[0072] Table 1 shows the minimum inhibitory concentrations (MICs) of all target compounds and positive controls against test bacteria and their HCl concentrations against human erythrocytes in this invention. 50 value.

[0073] Table 1

[0074] Table 2 shows the cytotoxicity experiments of all target compounds and positive control drugs of this invention on RAW264.7 macrophages.

[0075] Table 2

[0076] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An amphiphilic eugenol-quaternary phosphine salt hybrid, characterized in that, The structure of the compound is shown in Formula I: ， in: R 1 Selected from C 1-6 Alkyl, phenyl, heteroaryl, fused cycloalkyl, heterofused cycloyl, 3-6 membered saturated cycloalkyl, 3-6 membered saturated heterocyclic group; R 2 Selected from C 1-6 Alkyl, phenyl, heteroaryl, fused cycloalkyl, heterofused cycloyl, 3-6 membered saturated cycloalkyl, 3-6 membered saturated heterocyclic group; R 3 Selected from hydroxyl, amino, amide, guanidinyl, thiol, halogen, C 1-6 Alkyl, halogen-substituted C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 alkylamine group, C 1-6 Alkylthio, phenyl; R 4 Selected from hydrogen, hydroxyl, amino, amide, guanidinyl, mercapto, halogen, C 1-6 Alkyl, halogen-substituted C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 alkylamine group, C 1-6 Alkylthio, phenyl; R 5 Selected from hydrogen, hydroxyl, amino, amide, guanidinyl, mercapto, halogen, C 1-6 Alkyl, halogen-substituted C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 alkylamine group, C 1-6 Alkylthio, phenyl; n is selected from 0, 1, 2, 3, 4, 5, 6, 7, 8; X is selected from fluorine, chlorine, bromine, iodine, trifluoroacetate, sulfate, hydrochloric acid, nitric acid, acetic acid, and formic acid.

2. The amphiphilic eugenol-quaternary phosphine salt hybrid according to claim 1, characterized in that: The compound is selected from: 。 3. A solvate or deuterated compound of the compound according to any one of claims 1-2.

4. A pharmaceutical composition comprising a compound according to any one of claims 1-3 or a solvate or deuterated compound of the compound according to claim 3, and pharmaceutically acceptable excipients.

5. Use of the compound of any one of claims 1-4, or a pharmaceutically acceptable salt thereof, or a solvate or deuterated compound of the compound of claim 4, in the preparation of an antibacterial drug.

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