Application of biphenyl compound in resisting drug-resistant bacteria and product

Abstract

The invention belongs to the field of biological medicine, and particularly relates to application of a biphenyl compound in resisting drug-resistant bacteria and a product. The invention provides an application of 2, 4-dihydroxy-4 '-pentylbiphenyl and / or 3, 5-dihydroxy-4'-pentylbiphenyl in preparation of a product for resisting drug-resistant bacteria, and a preparation method of the 2, 4-dihydroxy-4 '-pentylbiphenyl. The result of the embodiment shows that compared with other antibiotics such as penicillin, ceftaroline fosamil, oxacillin and levofloxacin, the 2, 4-dihydroxy-4 '-pentylbiphenyl and / or the 3, 5-dihydroxy-4'-pentylbiphenyl can effectively inhibit various drug-resistant bacteria, and the effect is good. The 3, 5-dihydroxy-4 '-pentylbiphenyl can damage cell nucleuses by destroying cell membranes so as to achieve an antibacterial effect, and has a remarkable inhibition effect on MRSA (Methicillin-Resistant Staphylococcus Aureus). The 2, 4-dihydroxy-4 '-pentylbiphenyl and the 3, 5-dihydroxy-4'-pentylbiphenyl disclosed by the invention are used for resisting drug-resistant bacteria, can effectively inhibit or kill various drug-resistant bacteria, and have a good effect.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of biological medicine, and particularly relates to application of a biphenyl compound in resisting drug-resistant bacteria and a product. BACKGROUND

[0002] The abuse of antibiotics has led to the emergence of a large number of drug-resistant strains, resulting in an increasing use of antibiotics and a decreasing drug efficacy, and finally forming a vicious cycle. In recent years, the emergence of pan-drug resistant'superbugs' has brought unprecedented challenges to clinical treatment and infection prevention and control. Therefore, developing anti-infection strategies with innovation and sustainability has become a global consensus. However, the current traditional antibiotic research and development mode has problems such as insufficient motivation and long research and development cycle, and it is urgent to strengthen the research and development of antibacterial compounds capable of inhibiting drug-resistant strains.

[0003] Plantibactins are low-molecular-weight antibacterial compounds synthesized by plants themselves and accumulated in the body after the plants contact pathogenic microorganisms. Biphenyl plantibactins are mainly derived from Rosoideae plants such as apples (Malus domestica), pears (Pyrus communis) and Sorbus pohuashanensis, and the like, and are de novo synthesized when the plants are infected by pathogenic microorganisms. These biphenyl plantibactins have good antibacterial activity, and the structural design and synthesis of biphenyl plantibactin derivatives have become a new product research and development direction. 2,4-dihydroxy-4'-pentyl biphenyl and 3,5-dihydroxy-4'-pentyl biphenyl are two biphenyl plantibactin derivatives synthesized by Suzuki-Miyaura reaction, and the existing technology only reports that 2,4-dihydroxy-4'-pentyl biphenyl and 3,5-dihydroxy-4'-pentyl biphenyl have certain anti-invasive fungal activity and low cytotoxicity. SUMMARY

[0004] The application aims to provide application of 2,4-dihydroxy-4'-pentyl biphenyl and / or 3,5-dihydroxy-4'-pentyl biphenyl in preparing a product for resisting drug-resistant bacteria, and the 2,4-dihydroxy-4'-pentyl biphenyl and / or 3,5-dihydroxy-4'-pentyl biphenyl can effectively inhibit drug-resistant bacteria.

[0005] To solve the above technical problems, the application provides the following technical scheme.

[0006] The application provides application of 2,4-dihydroxy-4'-pentyl biphenyl and / or 3,5-dihydroxy-4'-pentyl biphenyl in preparing a product for resisting drug-resistant bacteria, the structural formula of the 2,4-dihydroxy-4'-pentyl biphenyl is shown as formula I, and the structural formula of the 3,5-dihydroxy-4'-pentyl biphenyl is shown as formula II.

[0007]

[0008] Preferably, the application form of 2,4-dihydroxy-4'-pentylbiphenyl also includes one or more of the pharmaceutically acceptable salt, crystal and salt crystal of 2,4-dihydroxy-4'-pentylbiphenyl.

[0009] The application form of 3,5-dihydroxy-4'-pentylbiphenyl also includes one or more of the pharmaceutically acceptable salt, crystal and salt crystal of 3,5-dihydroxy-4'-pentylbiphenyl.

[0010] Preferably, the product includes one or more of the pharmaceutical product, health product and disinfectant.

[0011] Preferably, the drug-resistant bacteria include one or more of methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, multi-drug resistant Enterococcus faecalis and multi-drug resistant Enterococcus faecium.

[0012] Preferably, the multi-drug resistant Enterococcus faecalis includes Enterococcus faecalis numbered as ATCC 29212; the multi-drug resistant Enterococcus faecium includes Enterococcus faecium numbered as ATCC 19434.

[0013] Preferably, the anti-drug-resistant bacteria includes inhibiting and / or killing drug-resistant bacteria.

[0014] The application provides an anti-drug-resistant bacteria product, wherein the effective component of the product includes 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl and pharmaceutically acceptable excipients; the structural formula of the 2,4-dihydroxy-4'-pentylbiphenyl is shown as formula I; the structural formula of the 3,5-dihydroxy-4'-pentylbiphenyl is shown as formula II,

[0015]

[0016] Preferably, the application form of 2,4-dihydroxy-4'-pentylbiphenyl also includes one or more of the pharmaceutically acceptable salt, crystal and salt crystal of 2,4-dihydroxy-4'-pentylbiphenyl.

[0017] The application form of 3,5-dihydroxy-4'-pentylbiphenyl also includes one or more of the pharmaceutically acceptable salt, crystal and salt crystal of 3,5-dihydroxy-4'-pentylbiphenyl.

[0018] Preferably, the dosage form of the product includes one or more of liquid agent, solid agent, semi-solid agent and gaseous agent.

[0019] Beneficial effects of the present invention: The present invention provides the application of 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl in the preparation of products against drug-resistant bacteria. Prior art reports indicate that 2,4-dihydroxy-4'-pentylbiphenyl and 3,5-dihydroxy-4'-pentylbiphenyl are effective against invasive fungi. The present invention has found that 2,4-dihydroxy-4'-pentylbiphenyl and 3,5-dihydroxy-4'-pentylbiphenyl are also effective against drug-resistant bacteria. Drug-resistant bacteria, also known as antibiotic-resistant bacteria, are bacteria that have developed resistance to antibacterial drugs (such as antibiotics) that could originally inhibit or kill them, and are therefore difficult to eradicate.

[0020] The results of the examples show that, compared with other antibiotics such as penicillin, cefuroxime azoxystrobin, oxacillin, and levofloxacin, 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl can effectively inhibit a variety of drug-resistant bacteria, with superior efficacy. 3,5-dihydroxy-4'-pentylbiphenyl achieves its antibacterial effect by disrupting the cell membrane and thereby damaging the cell nucleus, and MRSA exhibits a "quorum sensing" phenomenon after inhibition.

[0021] The 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl of the present invention can resist drug-resistant bacteria, have good application effects, and ensure future medical safety for humans. Attached Figure Description

[0022] Biphenyl compound Image of MRSA cell damage observed under a super-resolution microscope in the control group;

[0023] MRSA-1 Image of MRSA cell damage observed under a super-resolution microscope after 23 hours of treatment;

[0024] MRSA-2 The graph shows the change in the bactericidal effect of different concentrations of 3,5-dihydroxy-4'-pentylbiphenyl on MRSA over time. Detailed Implementation

[0025] This invention provides the use of 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl in the preparation of products for the treatment of drug-resistant bacteria.

[0026] The synthesis method of 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl described in the application is referred to the prior art Jianchuan Liu, Jian Yang, Shuxin Lei, Mingfan Wang, Yanni Ma, Rui Yang. Natural phytoalexins inspired the discovery of new biphenyls as potent antifungal agents for treatment of invasive fungal infections [J]. European Journal of Medicinal Chemistry, 2023, 261, 115842. https: / / doi.org / 10.1016 / j.ejmech.2023.115842.

[0027] The 2,4-dihydroxy-4'-pentylbiphenyl described in the application is denoted as biphenyl compound 23e, and the English name is: 4'-pentyl-[1,1'-biphenyl]-2,4-diol. The chemical formula of the 2,4-dihydroxy-4'-pentylbiphenyl described in the application is C 12 H 10 O2, and the structural formula is as shown in formula I.

[0028] The 3,5-dihydroxy-4'-pentylbiphenyl described in the application is denoted as biphenyl compound 23h, and the English name is 4'-pentyl-[1,1'-biphenyl]-3,5-diol. The chemical formula of the 3,5-dihydroxy-4'-pentylbiphenyl described in the application is C 12 H 12 O2, and the structural formula is as shown in formula II.

[0029]

[0030]

[0031] As an optional embodiment, the application form of the 2,4-dihydroxy-4'-pentylbiphenyl described in the application also includes one or more of the pharmaceutically acceptable salt, crystal and salt crystal of 2,4-dihydroxy-4'-pentylbiphenyl.

[0032] The application form of the 3,5-dihydroxy-4'-pentylbiphenyl described in the application also includes one or more of the pharmaceutically acceptable salt, crystal and salt crystal of 3,5-dihydroxy-4'-pentylbiphenyl.

[0033] As an optional embodiment, the dosage form of the product of the present application includes one or more than two of liquid agent, solid agent, semi-solid agent and gaseous agent. The present application does not have special limitations on the preparation method of the liquid agent, solid agent, semi-solid agent and gaseous agent, and conventional methods can be used.

[0034] The 2,4-dihydroxy-4'-pentyl biphenyl and / or 3,5-dihydroxy-4'-pentyl biphenyl of the present application can resist drug-resistant bacteria. As an optional embodiment, the drug-resistant bacteria of the present application include inhibiting and / or killing drug-resistant bacteria.

[0035] As an optional embodiment, the drug-resistant bacteria of the present application include one or more than two of methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, multi-drug resistant Enterococcus faecalis and multi-drug resistant Enterococcus faecium. In a specific embodiment of the present application, the application effect of 2,4-dihydroxy-4'-pentyl biphenyl and / or 3,5-dihydroxy-4'-pentyl biphenyl is verified by using multi-drug resistant Enterococcus faecalis numbered ATCC 29212, multi-drug resistant Enterococcus faecium numbered ATCC 19434, methicillin-resistant Staphylococcus epidermidis numbered ATCC 12228, MRSA numbered ATCC 43300 and two strains of MRSA disclosed in the prior art (https: / / doi.org / 10.1128 / spectrum.02430-22, i.e. Doi:10.1128 / spectrum.02430-22), a total of 6 strains.

[0036] The results of the examples show that 2,4-dihydroxy-4'-pentyl biphenyl and 3,5-dihydroxy-4'-pentyl biphenyl exhibit good activity against clinical drug-resistant bacteria, are effective against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE), multi-drug resistant Enterococcus faecalis (MREf) and multi-drug resistant Enterococcus faecium (MREF), the MIC value is lower than that of the positive control drug, and has potential for clinical application. The MIC value of 2,4-dihydroxy-4'-pentyl biphenyl and 3,5-dihydroxy-4'-pentyl biphenyl against bacteria is low, and the effect is better than that of penicillin, ceftaroline fosamil, oxacillin and levofloxacin. 3,5-dihydroxy-4'-pentyl biphenyl can damage the cell nucleus by destroying the cell membrane to achieve antibacterial effect, and MRSA will exhibit the phenomenon of "quorum sensing" after being inhibited.

[0037] As an optional embodiment, the product of the present application comprises one or more than two of a drug, a health product and a disinfectant. As an optional embodiment, the concentration of 2,4-dihydroxy-4'-pentylbiphenyl in the product is ≥10 μg / mL, and can also be 20-50 μg / mL, and more preferably 40 μg / mL. The concentration of 3,5-dihydroxy-4'-pentylbiphenyl in the product is ≥10 μg / mL, and can also be 20-45 μg / mL, and more preferably 40 μg / mL.

[0038] The results of the examples show that when the concentration of 3,5-dihydroxy-4'-pentylbiphenyl is 4×MIC, complete killing of MRSA can be achieved within 24 h (bacterial colony number ≤ detection limit represents complete killing).

[0039] The application concentration of 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl of the present application is preferably 2×MIC-4×MIC, and more preferably 4×MIC, so as to achieve a rapid and thorough sterilization effect. The preferred concentration is based on in vitro sterilization experiments, and the actual clinical concentration can be adjusted according to the PK / PD model.

[0040] The present application provides a product for resisting drug-resistant bacteria, and the effective components of the product comprise 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl and pharmaceutically acceptable excipients. The concentration of 2,4-dihydroxy-4'-pentylbiphenyl in the product of the present application has been discussed above, and will not be repeated here. The concentration of 3,5-dihydroxy-4'-pentylbiphenyl in the product of the present application has been discussed above, and will not be repeated here.

[0041] The dosage form of the product of the present application comprises one or more than two of a liquid agent, a solid agent, a semi-solid agent and a gaseous agent. The present application does not have special limitations on the preparation method of the liquid agent, the solid agent, the semi-solid agent and the gaseous agent, and a conventional method can be used.

[0042] In order to further illustrate the present application, the technical solutions provided by the present application are described in detail below in combination with the drawings and examples, but they should not be understood as limiting the scope of protection of the present application.

[0043] The strain information and source used in the following examples are shown in Table 1.

[0044] Table 1 Information and source of different strains

[0045]

[0046]

[0047] Note: MRSA is methicillin-resistant Staphylococcus aureus.

[0048] The corresponding literature name of https: / / doi.org / 10.1128 / spectrum.02430-22 is "Kaiyu Cui, Weifeng Yang, Zhiyuan Liu, Guijian Liu, Dongying Li, Yanan Sun, Gaiying He, Shuhua Ma, Yu Cao, Xuefan Jiang, Sylvie Chevalier, Pierre Cornelis, Qing Wei, Yi Wang. Chenodeoxycholic acid-Amikacin combination enhances eradication of Staphylococcus aureus [J]. Microbiology spectrum, 2023, 11(1): e0243022".

[0049] Staphylococcus epidermidis is MRSE, which is methicillin-resistant Staphylococcus epidermidis.

[0050] ATCC 29212 is multidrug-resistant Enterococcus faecalis (MREf);

[0051] ATCC 19434 is multidrug-resistant Enterococcus faecalis (MREf).

[0052] The trypsin soybean broth (TSB) was prepared by using a commercially available TSB medium, which was purchased from HuanKai Microorganism with the number 024051.

[0053] The brand of MHB medium is Solarbio, and the item number is M8556.

[0054] The synthesis method of biphenyl compound 23e (i.e. 2,4-dihydroxy-4'-pentylbiphenyl, abbreviated as 23e) and biphenyl compound 23h (i.e. 3,5-dihydroxy-4'-pentylbiphenyl, abbreviated as 23h) is described in the prior art (Jianchuan Liu, Jian Yang, Shuxin Lei, Mingfan Wang, Yanni Ma, Rui Yang. Natural phytoalexins inspired the discovery of new biphenyls as potent antifungal agents for treatment of invasive fungal infections [J]. European Journal of Medicinal Chemistry, 2023, 261, 115842. https: / / doi.org / 10.1016 / j.ejmech.2023.115842.)

[0055] The minimum inhibitory concentration (MIC) value determination of the biphenyl compounds described in the present application follows the standard document established by the American Clinical and Laboratory Standards Association (CLSI), and a systematic evaluation system is established by the micro-broth dilution method.

[0056] The biphenyl compound 23e, the biphenyl compound 23h, the ceftolozane, the oxacillin and the penicillin are all dissolved in DMSO (dimethyl sulfoxide) first, and then diluted in a trypticase soy broth medium.

[0057] Example 1

[0058] 1. Determination of the activity of the biphenyl compound 23e and the biphenyl compound 23h against clinically drug-resistant bacteria

[0059] Prepare a trypticase soy broth medium, calibrate the pH value to 7.3±0.1, activate the drug-resistant strain at 37°C with 120 rpm oscillation for 8h, wash the activated strain by centrifugation for 3 times, and adjust the concentration of the obtained bacterial suspension to 1×10 8 CFU / mL, and verify the accuracy by plate counting method.

[0060] Treatment 1 (MRSA-1 strain): in a sterile 96-well plate, add 100μL of MRSA-1 strain bacterial suspension to each well, and dilute the concentration of the added bacterial suspension to 1×10 6CFU / mL; 100 μL of biphenyl compound 23e solution was added to the first well to make the final concentration of biphenyl compound 23e in the well 640 μg / mL, and then 100 μL of the mixture was taken from the first well and added to the second well, and the dilution was performed in the same manner, so that the final concentration of biphenyl compound 23e in each well was 320 μg / mL, 160 μg / mL, 80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL, and 0.625 μg / mL, respectively.

[0061] Treatment 2 (MRSA-1 strain): 100 μL of MRSA-1 strain bacterial suspension was added to each well of a sterile 96-well plate, and the concentration of the bacterial suspension added was diluted to 1 x 10 6 CFU / mL; 100 μL of biphenyl compound 23e solution was added to the first well to make the final concentration of biphenyl compound 23e in the well 640 μg / mL, and then 100 μL of the mixture was taken from the first well and added to the second well, and the dilution was performed in the same manner, so that the final concentration of biphenyl compound 23e in each well was 320 μg / mL, 160 μg / mL, 80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL, and 0.625 μg / mL, respectively.

[0062] Treatment 3 (MRSA-2 strain): The same as treatment 1, except that the MRSA-1 strain bacterial suspension was replaced by the MRSA-2 strain bacterial suspension.

[0063] Treatment 4 (MRSA-2 strain): The same as treatment 2, except that the MRSA-1 strain bacterial suspension was replaced by the MRSA-2 strain bacterial suspension.

[0064] Treatment 5 (MRSA-3 strain): The same as treatment 1, except that the MRSA-1 strain bacterial suspension was replaced by the MRSA-3 strain bacterial suspension.

[0065] Treatment 6 (MRSA-3 strain): The same as treatment 2, except that the MRSA-1 strain bacterial suspension was replaced by the MRSA-3 strain bacterial suspension.

[0066] Positive reference 1 (ceftaroline fosamil): 100 μL of MRSA-1 strain bacterial suspension was added to each well of a sterile 96-well plate, and the concentration of the bacterial suspension added was diluted to 1 x 10 6CFU / mL; 100 μL of cefoperazone solution was added to the first well to make the final concentration of cefoperazone in the well 640 μg / mL, then 100 μL of the mixture was taken from the first well and added to the second well, and the dilution was repeated to make the final concentration of cefoperazone in the well 320 μg / mL, 160 μg / mL, 80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL and 0.625 μg / mL, respectively.

[0067] Positive reference 2 (cefoperazone): same as positive reference 1, the only difference is that the MRSA-1 strain suspension is replaced by the MRSA-2 strain suspension.

[0068] Positive reference 3 (cefoperazone): same as positive reference 1, the only difference is that the MRSA-1 strain suspension is replaced by the MRSA-3 strain suspension.

[0069] Positive reference 4 (oxacillin): same as positive reference 1, the only difference is that cefoperazone is replaced by oxacillin.

[0070] Positive reference 5 (oxacillin): same as positive reference 2, the only difference is that cefoperazone is replaced by oxacillin.

[0071] Positive reference 6 (oxacillin): same as positive reference 3, the only difference is that cefoperazone is replaced by oxacillin.

[0072] Blank control group: only 100 μL of sterilized trypticase soy broth medium was added.

[0073] Growth control group: 100 μL of sterilized trypticase soy broth medium was added, and the DMSO content was the same as that of the treatment group.

[0074] Each treatment group had three biological replicates, and the blank control group (sterilized medium), growth control group (no drug medium) and positive reference group (cefoperazone, oxacillin) were included simultaneously. After the addition was completed, the 96-well plate was transferred to a constant temperature and humidity incubator, and incubated at 37°C and 80% relative humidity for 24 hours. The results are shown in Table 2.

[0075] Table 2 MIC values (μg / mL) of biphenyl compounds 23e and 23h against three strains of MRSA

[0076] MRSA-3 Biphenyl compound 23e Biphenyl compound 23h Cefpirome Oxacillin 5 5 10 Biphenyl compound 10 5 10 Staphylococcus epidermidis 32 32 64 Penicillin 16 64 512

[0077] Treatment 7 (ATCC 12228 strain, referred to as strain 4): in a sterile 96-well plate, 100 μL of strain 4 suspension was added to each well, and the concentration of the added bacterial suspension was diluted to 1 x 106 CFU / mL; 100 μL of biphenyl compound 23e solution was added to the first well to make the final concentration of biphenyl compound 23e in the well 640 μg / mL, then 100 μL of the mixture was taken from the first well and added to the second well, and the dilution was repeated to make the final concentration of biphenyl compound 23e in each well 320 μg / mL, 160 μg / mL, 80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL and 0.625 μg / mL.

[0078] Treatment 8 (ATCC 12228 strain, referred to as strain 4): same as treatment 7, the only difference is that biphenyl compound 23e is replaced by biphenyl compound 23h.

[0079] Positive control 7 (penicillin): same as treatment 7, the only difference is that biphenyl compound 23e is replaced by penicillin.

[0080] Positive control 8 (oxacillin): same as treatment 7, the only difference is that biphenyl compound 23e is replaced by oxacillin.

[0081] Blank control: only 100 μL of sterilized trypticase soy broth medium is added.

[0082] Growth control: 100 μL of sterilized trypticase soy broth medium is added, and the DMSO content is the same as that of the treatment group.

[0083] Each treatment group has three biological replicates, and the blank control (sterilized medium), growth control (no drug medium) and positive control (penicillin, oxacillin) are included simultaneously. After the addition of the sample is completed, the 96-well plate is transferred to a constant temperature and humidity incubator, and incubated at 37°C and 80% relative humidity for 24 hours. The results are shown in Table 3.

[0084] Table 3 MIC values of biphenyl compounds 23e and 23h for MRSE (μg / mL)

[0085] Oxacillin Biphenyl compound 23e 10 23h 10 Enterococcus faecalis 64 Enterococcus faecium 16

[0086] Treatment 9 (ATCC 29212, referred to as strain 5): in a sterile 96-well plate, 100 μL of strain 5 bacterial suspension was added to each well, and the concentration of the bacterial suspension was diluted to 1 x 10 6CFU / mL; 100 μL of the solution of biphenyl compound 23e was added to the first well to make the final concentration of biphenyl compound 23e in the well 640 μg / mL, then 100 μL of the mixture was taken from the first well and added to the second well, and the dilution was carried out in turn to make the final concentration of biphenyl compound 23e in each well 320 μg / mL, 160 μg / mL, 80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL and 0.625 μg / mL.

[0087] Treatment 10 (ATCC 29212, abbreviated as strain 5): the same as treatment 9, the only difference is that biphenyl compound 23e is replaced by biphenyl compound 23h.

[0088] Positive control 7 (penicillin): the same as treatment 9, the only difference is that biphenyl compound 23e is replaced by penicillin.

[0089] Positive control 8 (levofloxacin): the same as treatment 9, the only difference is that biphenyl compound 23e is replaced by levofloxacin.

[0090] Treatment 11 (ATCC 19434, abbreviated as strain 6): in a sterile 96-well plate, 100 μL of the bacterial suspension of strain 6 was added to each well, and the concentration of the bacterial suspension was diluted to 1 x 10 6 CFU / mL; 100 μL of the solution of biphenyl compound 23e was added to the first well to make the final concentration of biphenyl compound 23e in the well 640 μg / mL, then 100 μL of the mixture was taken from the first well and added to the second well, and the dilution was carried out in turn to make the final concentration of biphenyl compound 23e in each well 320 μg / mL, 160 μg / mL, 80 μg / mL, 40 μg / mL, 20 μg / mL, 10 μg / mL, 5 μg / mL, 2.5 μg / mL, 1.25 μg / mL and 0.625 μg / mL.

[0091] Treatment 12 (ATCC 19434, abbreviated as strain 6): the same as treatment 11, the only difference is that biphenyl compound 23e is replaced by biphenyl compound 23h.

[0092] Positive control 9 (penicillin): the same as treatment 11, the only difference is that biphenyl compound 23e is replaced by penicillin.

[0093] Positive control 10 (levofloxacin): the same as treatment 11, the only difference is that biphenyl compound 23e is replaced by levofloxacin.

[0094] Blank control: only 100 μL of sterilized trypticase soy broth medium was added.

[0095] Growth control: add 100 μL sterilized trypticase soy broth medium, with the same DMSO content as the treatment group.

[0096] Each treatment group was set up with three biological replicates, and blank control (sterilized medium), growth control (no drug medium) and positive reference group (penicillin and levofloxacin) were included simultaneously. After the addition was completed, the 96-well plate was transferred to a constant temperature and humidity incubator, and incubated statically at 37°C, 80% relative humidity for 24h.

[0097] Each treatment group was set up with three biological replicates, and blank control (sterilized medium), growth control (no drug medium) and positive reference group (penicillin, oxacillin) were included simultaneously. After the addition was completed, the 96-well plate was transferred to a constant temperature and humidity incubator, and incubated statically at 37°C, 80% relative humidity for 24h. The results are shown in Table 4.

[0098] Table 4 MIC values of biphenyl compounds 23e and 23h against MREf and MREF (μg / mL)

[0099] Penicillin Levofloxacin Figures 1-2 23e 10 10 23h 10 10 Figures 1-2 128 128 Figure 1 8 8

[0100] According to Tables 2-4, biphenyl compounds 23e and 23h showed good activity against clinically resistant bacteria, and were effective against multiple clinically resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE), multi-drug resistant Enterococcus faecalis (MREf) and multi-drug resistant Enterococcus faecium (MREF), with low MIC values and potential for clinical application.

[0101] 2. Ultra-high resolution microscopic imaging system to observe bacterial morphology

[0102] Treatment group: the MRSA-1 bacterial solution in logarithmic growth phase was obtained by culturing the strain in MHB medium, and the viable cell count of the bacterial solution was adjusted to 5x10 6 CFU / ml, and 1 / 2 MIC of biphenyl compound 23h was added to the bacterial solution.

[0103] Blank group (control): only contains the bacterial solution obtained by culturing in MHB medium.

[0104] Both groups were cultured at 37°C, 220 rpm for 1h.

[0105] Nile red and DAPI were used for co-staining. The Nile red dye concentration in the bacterial solution was 10 pg / mL, and the DAPI dye concentration was 10 pg / mL. After incubation in the dark for 10 min, centrifugation was performed at 4°C and 3000 rpm for 10 min, and the supernatant was discarded. The bacterial cells were rinsed with PBS buffer for 3 times and resuspended. The bacterial solution was transferred to a glass slide and placed in a dark box. The sample was inverted on the sample stage of the ultra-high resolution microscopic imaging system (STEDYCON, Abberior), and a clear field was selected for photography. Each group had 3 biological replicates. ImageJ software was used to process the pictures with 300x300 pixels and 40 pixel / ul units. The results are shown in Figure 3 , Biphenyl compound Nile red is Nile red dye; DAPI refers to 4', 6-diamidino-2-phenylindole dihydrochloride dye; Merge represents superimposed field.

[0106] It can be seen that the Nile red fluorescence staining results show that the red fluorescence intensity of the cell membrane of the drug administration group is weaker than that of the control group, indicating that the biphenyl compound 23h can damage the cell membrane and reduce the lipid. The DAPI fluorescence staining results show that the blue fluorescence of the drug administration group is significantly weaker than that of the control group and the cell nucleus is deformed, indicating that the biphenyl compound 23h can damage the cell nucleus. In addition, before fluorescence staining, the cells in the control group were in a single dispersed state, but after treatment with 23h, the cells aggregated and several cells appeared simultaneously in the field of view. It can be seen that during the inhibition of the biphenyl compound, the cells aggregated. MRSA-1 The results show that the biphenyl compound 23h can damage the cell nucleus by destroying the cell membrane to achieve antibacterial effect, and the MRSA will exhibit a "quorum sensing" phenomenon after being inhibited.

[0107] 3. Time-kill curve

[0108] The dynamic killing process of the antibacterial product was observed, and the killing curve was drawn with time as the horizontal coordinate and the number of colonies as the vertical coordinate, so as to determine or compare the strength and speed of the antibacterial product, as well as the optimal antibacterial concentration.

[0109] Treatment 1: The strain was cultured in MHB medium to obtain the MRSA-1 bacterial solution in the logarithmic growth phase, and the viable cell number of the bacterial solution was adjusted to 5x10 5 CFU / ml. The biphenyl compound 23h was added to the bacterial solution, and the bacterial solution contained 1xMIC concentration of the biphenyl compound 23h.

[0110] Treatment 2: The strain was cultured in MHB medium to obtain the bacterial solution in the logarithmic growth phase, and the viable cell number of the bacterial solution was adjusted to 5x10 5CFU / ml, and the biphenyl compound 23h was added to the bacterial solution, and the concentration of the biphenyl compound 23h in the bacterial solution was 2xMIC.

[0111] Treatment 3: The bacterial solution was obtained by culturing the strain in MHB medium, and the viable cell count of the bacterial solution was adjusted to 5x10 5 CFU / ml, and the biphenyl compound 23h was added to the bacterial solution, and the concentration of the biphenyl compound 23h in the bacterial solution was 4xMIC.

[0112] Blank group: only containing the bacterial solution obtained by culturing in MHB medium.

[0113] Each group was set up with 3 biological replicates. Two groups were cultured at 37°C, and at 0h, 4h, 8h, 12h, and 24h, the bacterial suspension was taken out, diluted by 1:10, inoculated on LB plates, and incubated at 37°C for 24h, and the plates with 30-300 colonies were selected for counting.

[0114] The changes of the bactericidal effect of different concentrations of the biphenyl compound 23h on MRSA over time are shown in MRSA-2 MRSA-3 Biphenyl compound 23e Biphenyl compound 23h Cefpirome Oxacillin Biphenyl compound Staphylococcus epidermidis Penicillin Oxacillin Biphenyl compound Enterococcus faecalis Enterococcus faecium Penicillin Levofloxacin Figures 1-2 Figures 1-2 Figure 1 Figure 3 and Table 5. It can be seen that in the blank group, the number of MRSA-1 bacteria increased over time, reaching 8.5 Log 10 CFU / mL at 24h. At 1xMIC, the number of bacteria remained relatively stable. At 2xMIC, the number of bacteria gradually decreased, reaching nearly 2 Log 10 CFU / mL at 12h. At 4xMIC, the number of bacteria rapidly decreased, reaching nearly 2 Log 10 CFU / mL at 8h, indicating that the 4xMIC biphenyl compound had the strongest bactericidal effect on MRSA, and the number of bacteria was almost completely inhibited.

[0115] Table 5 Total number of MRSA colonies log 10 (CFU / mL)

[0116]

[0117] In summary, 2,4-dihydroxy-4'-pentyl biphenyl and 3,5-dihydroxy-4'-pentyl biphenyl can effectively inhibit a variety of clinically drug-resistant bacteria, and have good effects.

[0118] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application, not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, which are within the scope of protection of the present application.

Claims

1. Use of 2,4-dihydroxy-4'-pentylbiphenyl and / or 3,5-dihydroxy-4'-pentylbiphenyl in the preparation of a product against drug-resistant bacteria, wherein the 2,4-dihydroxy-4'-pentylbiphenyl has a structural formula as shown in Formula I; and the 3,5-dihydroxy-4'-pentylbiphenyl has a structural formula as shown in Formula II.

2. Use according to claim 1, characterized in that, The 2,4-dihydroxy-4'-pentylbiphenyl also includes one or more than two of a pharmaceutically acceptable salt, a crystal and a salt crystal of the 2,4-dihydroxy-4'-pentylbiphenyl. The 3,5-dihydroxy-4'-pentylbiphenyl also includes one or more than two of a pharmaceutically acceptable salt, a crystal and a salt crystal of the 3,5-dihydroxy-4'-pentylbiphenyl.

3. Use according to claim 1, characterized in that, The product includes one or more than two of a drug, a health care product and a disinfectant.

4. Use according to claim 1, characterized in that, The drug-resistant bacteria include one or more than two of methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, multi-drug resistant Enterococcus faecalis and multi-drug resistant Enterococcus faecium.

5. Use according to claim 4, characterized in that, The multi-drug resistant Enterococcus faecalis includes Enterococcus faecalis with an ATCC number of 29212.

6. Use according to claim 4, characterized in that, The multi-drug resistant Enterococcus faecium includes Enterococcus faecium with an ATCC number of 19434.

7. The use according to claim 1, characterized in that, The product against drug-resistant bacteria includes inhibiting and / or killing the drug-resistant bacteria.

8. A product against drug resistant bacteria, characterized in that, The product includes one or more than two of a liquid, a solid, a semi-solid and a gaseous dosage form.

9. The use according to claim 1, characterized in that, The product includes one or more than two of a liquid, a solid, a semi-solid and a gaseous dosage form. ​ 10. The product of claim 7, wherein ​

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