CN120208814B

CN120208814B - Adamantane modification-based antibacterial peptide mimics and application thereof

Info

Publication number: CN120208814B
Application number: CN202510275595.XA
Authority: CN
Inventors: 王凯荣; 苏洁; 贺宇航; 李敏
Original assignee: Lanzhou University
Current assignee: Lanzhou University
Priority date: 2025-03-10
Filing date: 2025-03-10
Publication date: 2025-11-11
Anticipated expiration: 2045-03-10
Also published as: CN120208814A

Abstract

This invention discloses an adamantane-modified antimicrobial peptide mimic and its applications. The invention involves amide condensation of Fmoc amino acids to obtain compounds with carboxyl-terminally protected adamantane-amine or Boc-protected fatty amines. Then, Fmoc groups are removed by piperidine to obtain a series of crude products containing adamantane-amine modification and intermediate compounds modified with Boc-protected fatty amines. The intermediate compounds are further modified with adamantane acid by amide condensation to obtain compounds with amino-terminally protected adamantane acid. Then, other protecting groups are cleaved by trifluoroacetic acid to obtain a series of adamantane acid-modified crude products. The crude products are purified to obtain the adamantane-modified peptide mimic. The adamantane-modified peptide mimic of this invention is used to prepare drugs for infectious diseases caused by susceptible and drug-resistant bacteria, exhibiting high antibacterial activity, low toxicity, and independence from traditional drug resistance mechanisms.

Description

Adamantane modification-based antibacterial peptide mimics and application thereof

Technical Field

The invention belongs to the field of pharmaceutical chemistry, and particularly relates to an adamantane-modified antibacterial peptide mimic and application thereof.

Background

In the 20 th century, the discovery and development of antibiotics was a key achievement in the medical field, significantly reducing the incidence of disease and mortality caused by bacterial infections. However, the widespread spread of bacteria that develop resistance to almost all antibiotics on the market, such that current treatments may fail, constitutes a serious risk. In addition, the evolution and spread of multi-drug resistant bacteria not only threatens human health, but also has become a major threat to global healthcare. Thus, there is an urgent need to explore and develop novel antibacterial agents to combat infections caused by drug-resistant bacteria.

Cationic antimicrobial peptides (CAMPs) are considered potential antimicrobial agents due to their broad-spectrum antimicrobial activity and unique membrane disruption patterns. CAMPs, present in almost all organisms, constitutes the first line of defense of the innate immune system. Most CAMPs exhibit antibacterial activity against various bacteria, fungi, protozoa and viruses. They generally employ amphiphilic structures in which hydrophilic and hydrophobic residues separate into opposing regions in the presence of solvents or interactions with cell membranes. For CAMPs, its mechanism of action involves interaction with the negative charge component of the bacterial cell membrane, resulting in increased cell permeability and ultimately cell death. Bacterial membranes are believed to be more negatively charged than mammalian membranes due to differences in the composition of bacterial cell membrane phospholipids, making AMPs selective for bacteria. Since AMPs are directed against bacteria that have specific binding sites, unlike traditional antibiotics, bacteria are less likely to develop resistance to them. AMPs appear to be promising candidates for antibacterial drugs, however, they suffer from several significant drawbacks in clinical use, such as potential toxicity to host cells, poor tissue distribution, and susceptibility to proteases. Furthermore, the high cost of synthesizing AMPs is another obstacle to their use as drug candidates.

Disclosure of Invention

To overcome the disadvantages and shortcomings of the prior art, a primary object of the present invention is to provide an antibacterial peptide mimetic based on adamantane modification.

It is another object of the present invention to provide the use of the above antibacterial peptide mimetic.

The invention is realized by the fact that the antibacterial peptide mimic is an adamantane modified peptidomimetic with a chemical structural formula shown in the following formula (I), or the antibacterial peptide mimic is a pharmaceutically acceptable salt of the adamantane modified peptidomimetic, a solvate of the pharmaceutically acceptable salt, or a stereoisomer, a tautomer or a complex of the adamantane modified peptidomimetic;

(I);

In formula (I), the R ₁ group is selected from 、、、Any one of them;

The R ₂ group is selected from 、、、、、、、、、、、、Any one of them;

The R ₃ group is selected from 、One of the following;

wherein m=2 or 4;n =1 or 2;p =0 to 4, and q=0 or 1.

Preferably, the adamantane modified peptoid is selected from any one of the following A1-A42;

。

Preferably, the pharmaceutically acceptable salts include salts with inorganic bases, salts with organic bases, salts with basic amino acids, salts with inorganic acids, salts with organic acids or salts with acidic amino acids.

Preferably, the salt of the inorganic base is selected from any one of ammonium salt, alkali metal salt and alkaline earth metal salt;

Preferably, the salt of the organic base is a salt of any one selected from cyclohexylamine, benzylamine, octylamine, ethanolamine, diethanolamine, diethylamine, triethylamine, ethylenediamine, procaine, morpholine, pyrroline, piperidine, N-ethylpiperidine, N-methylmorpholine and piperazine;

Preferably, the salt with a basic amino acid is a salt of a basic amino acid selected from any one of lysine, arginine, ornithine and histidine;

Preferably, the salt of the inorganic acid is selected from any one of hydrochloride, bromide, sulfate, phosphate and phosphate;

preferably, the salt of the organic acid is selected from any one of acetate, formate, propionate, lactate, citrate, fumarate, maleate, benzoate, tartrate, malate, methanesulfonate, ethanesulfonate, toluenesulfonate, and benzenesulfonate;

preferably, the salt with an acidic amino acid is a salt of an acidic amino acid selected from aspartic acid or glutamic acid.

Preferably, the alkali metal salt is sodium salt or potassium salt, and the alkaline earth metal salt is magnesium salt or calcium salt.

The invention further discloses application of the antibacterial peptide mimics in preparation of medicines for resisting bacterial or drug-resistant bacterial infection.

Preferably, the dosage form of the drug is selected from any one of oral preparation, injection, mucosal administration preparation and external preparation.

Preferably, the bacteria or drug resistant bacteria are selected from any one of drug resistant bacteria, gram positive bacilli, gram negative cocci, gram negative bacilli, klebsiella, enterobacteria, hafnia, enterobacteria, proteus, providencia, yersinia, gram negative bacteria, pseudomonas aeruginosa, strict anaerobe, mycoplasma and mycobacterium.

Aiming at the defects of the prior art, an innovative molecular structure is urgently needed, so that the advantages of the antibacterial peptide can be maintained, and the limitations of the antibacterial peptide can be avoided. In this case, small molecule antimicrobial peptide mimics that mimic AMPs structure have potential as potent antimicrobial agents. These mimics have a positive charge that facilitates interaction with negatively charged bacterial cell membranes or DNA. They exhibit hydrophilic and hydrophobic properties similar to AMPs, and resist enzymatic hydrolysis by avoiding peptide bonds recognized by proteases. In addition, they are easy to synthesize, are not affected by the traditional drug resistance mechanism, and are not easy to develop drug resistance common to traditional antibiotics. Based on this, the invention designs and synthesizes a series of small molecule cationic antibacterial peptide mimics by adding hydrophilic aliphatic diamine or hydrophobic adamantane on the amino or carboxyl terminal or side chain of amino acids such as phenylalanine, tryptophan, isoleucine, cysteine, methionine and lysine to enhance the amphiphilicity of the amino acids. Through the researches of antibacterial activity screening, antibacterial mechanism, bacterial drug resistance, stability, anti-biofilm property, treatment potential against infection caused by drug-resistant bacteria and the like, the antibacterial peptide mimics have good potential against drug-resistant bacteria infection and can be used for preparing drugs against bacterial or drug-resistant bacteria infection, wherein the bacteria are selected from drug-resistant bacteria (such as methicillin-resistant staphylococcus aureus and vancomycin-resistant enterococci), gram-positive bacteria (such as staphylococcus aureus, staphylococcus epidermidis, streptococcus (such as streptococcus agalactiae, enterococcus pneumoniae and streptococcus pyogenes)), gram-positive bacteria (such as bacillus anthracis, listeria monocytogenes and corynebacterium diphtheriae), gram-negative bacteria (such as neisseria gonorrhoeae) and gram-negative bacteria (such as escherichia coli, haemophilus influenzae, citrobacter (such as friendly citrobacter, polytrichum, and shigella), and shigella, and gram-positive bacteria (such as klebsiella, and oxygenobacteria), and bacteria (such as staphylococcus aureus, streptococcus, such as streptococcus, and pseudomonas, and garcina strain such as stenotrophomonas, and garcinia, and stenotrophomonas, and stena strain. In addition, the antibacterial spectrum includes Pseudomonas aeruginosa (e.g., pseudomonas aeruginosa and Mekkera) and strictly anaerobic bacteria such as Clostridium fragilis, pediococcus, streptococcus anaerobiosus and Clostridium, and Mycoplasma (e.g., mycoplasma pneumoniae, mycoplasma hominum and Mycoplasma urogenital tract), as well as Mycobacteria such as Mycobacterium tuberculosis.

Compared with the defects and shortcomings of the prior art, the invention has the following beneficial effects:

(1) According to the invention, amphipathy on a framework is changed in a mode of linking hydrophobic groups such as adamantane, fatty amine and the like and cationic groups on side chain mercapto groups of amino terminal, carboxyl terminal and cysteine of different amino terminals, so that adamantane modified peptoid for treating sensitive bacteria and drug-resistant bacteria infectious diseases is obtained;

(2) The antibacterial peptide mimic (adamantane modified peptidomimetic) can cause depolarization of cell membrane and damage the integrity of the cell membrane, can quickly sterilize, can inhibit formation of a biological membrane, has a certain biological membrane clearing activity, is not easy to induce bacterial drug resistance, has good activity of resisting gram positive bacteria, has good antibacterial activity on drug resistant bacteria such as methicillin-resistant staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE) and the like, can solve the problem of lack of drug resistant bacteria at present, has the functions of replacing or assisting the preparation of drugs for treating infectious diseases caused by various drug resistant bacteria by using antibiotics clinically at present, can be used for preparing drugs for treating infectious diseases caused by sensitive bacteria and drug resistant bacteria, and has high-efficiency antibacterial activity, low toxicity and is not influenced by traditional drug resistant mechanisms.

Drawings

FIG. 1 shows the hemolysis rate test of the adamantane modified peptidomimetics A8, A11, A19, A20, A25, A35 at a concentration of 100. Mu.g/mL on mouse red blood cells.

FIG. 2 shows cytotoxicity test of mouse fibroblast NIH 3T3 at concentrations of 100. Mu.g/mL of adamantane modified peptidomimetics A8, A11, A19, A20, A25, A35.

FIG. 3 is a kinetic determination of the sterilization of Staphylococcus aureus by adamantane modified peptidomimetics A8 and A11 at a concentration of 4 XMIC.

Fig. 4 shows that adamantane modified peptidomimetics A8 and a11 induce staphylococcus aureus resistance, with clinical antibiotic Amoxicillin used as a positive control.

FIG. 5 shows the effect of adamantane modified peptidomimetics A8 and A11 on the cell membrane potential of Staphylococcus aureus at concentrations of 1 XMIC, 2 XMIC and 4 XMIC, PBS was used as a negative control and 0.1% Triton X-100 was used as a positive control.

FIG. 6 shows the fluorescence intensity change of the adamantane modified peptidomimetics A8 and A11 after absorption by Staphylococcus aureus PI by flow cytometry, PBS was used as a negative control.

FIG. 7 is a photograph of fluorescence of Staphylococcus aureus after detection of adamantane modified peptidomimetics A8 and A11 by laser confocal microscopy and incubation with PI dye, PBS was used as a negative control.

FIG. 8 shows the destructive effect of adamantane modified peptidomimetics A8 and A11 on Staphylococcus aureus at a concentration of 4 XMIC as seen by biological freeze-dried transmission electron microscopy.

FIG. 9 shows inhibition of Staphylococcus aureus biofilm formation by adamantane modified peptidomimetics A8 and A11 at 1 XMIC, 2 XMIC and 4 XMIC concentrations.

Fig. 10 shows lung colony counts and lung tissue sections H & E staining results of mice after treatment of MRSA-infected mice with adamantane modified peptidomimetics A8 and a11, linezolid was used as a positive control.

FIG. 11 is H & E staining results of the number of mouse corneal colonies and corneal tissue sections after treatment of MRSA-infected mice with adamantane modified peptidomimetics A8 and A11, linezolid was used as a positive control.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

The instrument used in the invention comprises: circumferential decolorizing shaker (SK-O330, dalong Xinghuang laboratory instruments (Beijing), china), rotary evaporator (560-00000-00-0, heidolph, germany), time-of-flight mass spectrometer (Maxis G, bruker, germany), HPLC preparative chromatography (NU 3001, hanbang science, china), analytical chromatography (A02996, waters, USA), freeze dryer (CoolSafe-4,Gene Company Limited, china) constant temperature shaker (IS-RDD 3, suzhou Jiemen electronics Co., china), biosafety cabinet (BSC-1500 IIB2-X, jien Xinbeixi biotechnology Co., china), constant temperature incubator (LT-BIX 300M, lide ke (Shanghai) scientific instrument Co., ltd), desk top centrifuges (Thermo 75004250, sameidie technologies, USA), multifunctional enzyme labeling apparatus (FlexStation III, mevalonate instruments, USA), carbon dioxide cell incubator (CLM-170B-8-TC, taicaners high medical instruments, china), fluorescence microscope (U-LH 50HG, olympus, japan), micro nucleic acid protein meter (E113192, implen GmbH, germany), mouse laryngoscope and atomizer (yuanskadet biotechnology, china), tissue cryogrinder (JXFSPRP-CLN-48, shanghai information development, china), flow cytometry (NovoCyte Quanteon, agilent).

The reagents used were o-benzotriazole-N, N, N, N' -tetramethyl-Hexafluorophosphate (HBTU), 1-Hydroxybenzotriazole (HOBT), N, N-Diisopropylethylamine (DIPEA), trifluoroacetic acid (TFA) and Dichloromethane (DCM) were purchased from Sheen Siro technologies Co., ltd. N, N-Dimethylformamide (DMF) was supplied by BASF (Germany). Acetonitrile was supplied by Shanghai CINC high purity solvent Co., ltd (Shanghai, china). D, L-amino acids, available from Michael chemical technology Co. Diethyl ether, piperidine and hydrochloric acid were purchased from Shanxi Longjingji Inc. (China Shandong). Dimethyl sulfoxide (DMSO), 5,3- (4, 5-dimethylthiazole-2) -2, 5-diphenyltetrazolium bromide (MTT) was purchased from Tianjin light complex reagent Co. MH broth medium was purchased from Qingdao Gaokou Haibo Biotechnology Co., ltd, and PBS buffer was purchased from Wohai Weibull Biotechnology Co., ltd. TritonX-100 was purchased from Sigma Aldrich trade Co., ltd. RPMIDMEM Medium was purchased from Shanghai Dattschel Biotech Co. Fetal Bovine Serum (FBS) was purchased from Shanghai Dattschel Biotech Co. Pancreatin cell digests were purchased from beijing lanjiek technology limited. Agar powder was purchased from Beijing and Jie Ke technology Co.

Example 1

The synthetic routes of adamantane modified peptidomimetics A1, A3, A5, A7, A9, a11, a13, a15, a18, a28, 29, a31, a33, a35, a37, a39, a41 are as follows:

In a typical reaction, commercially available amino acids (0.5 mmol,1 eq), HOBT (0.6 mmol,81.08 mg,1.2eq), HBTU (0.6 mmol,227.54 mg,1.2eq) and DIPEA (1.2 mmol,155.1 mg,2.4eq) were added to DMF of 30 mL, and then amantadine solution (0.12 mmol) was added to react 3: 3 h at normal temperature in the above system, and the progress of the reaction was checked using a silica gel reaction plate, and after the completion of the reaction, 120 mL saturated saline and 60mL ethyl acetate were added to shake and wash the organic phase, and then the organic phase was washed with brine, dried over anhydrous sodium sulfate, and then the organic phase was evaporated under reduced pressure to obtain an intermediate product in a yield of 95% or more.

The intermediate obtained was not further treated, piperidine (1.5 mL), DBU (1.5 mL), tetrahydrofuran (47 mL) were added, the reaction was stirred for 1 hour, the solvent was stripped off under reduced pressure, and the addition of glacial diethyl ether was performed to give the crude product. If the above crude product has an unnecessary side chain protecting group, the crude product is dissolved by DCM, TFA and TIS are added for reaction for 3 hours at room temperature, and the final desired crude product is obtained.

Finally the final compound was obtained by further HPLC purification (see example 7 for details).

Example 2

The synthetic route for adamantane modified peptidomimetics a25, a26 is as follows:

in a typical reaction, commercially available amino acids (0.5 mmol,1 eq), HOBT (0.6 mmol,81.08 mg,1.2eq), HBTU (0.6 mmol,227.54 mg,1.2eq) and DIPEA (1.2 mmol,155.1 mg,2.4eq) were added to DMF of 30 mL, and adamantane methylamine solution (0.12 mmol) was added to react 3: 3 h at normal temperature in the above system, and the progress of the reaction was detected using a silica gel reaction plate.

After the completion of the reaction, 120 mL saturated saline and 60 mL ethyl acetate were added and washed with shaking, the organic phase was retained, then the organic layer was washed with saline, dried with anhydrous sodium sulfate, and then the organic phase was evaporated under reduced pressure to obtain an intermediate product in a yield of 95% or more.

Example 3

The synthetic route for adamantane modified peptidomimetics a21, a23 is as follows:

In a typical reaction, commercially available amino acids (0.5 mmol,1 eq), HOBT (0.6 mmol,81.08 mg,1.2eq), HBTU (0.6 mmol,227.54 mg,1.2eq) and DIPEA (1.2 mmol,155.1 mg,2.4eq) were added to DMF of 30 mL, and amantadine solution (0.12 mmol) was added thereto to react 3: 3 h at normal temperature in the above system, and the progress of the reaction was detected using a silica gel reaction plate. After the completion of the reaction, 120 mL saturated saline and 60 mL ethyl acetate were added and washed with shaking, the organic phase was retained, then the organic layer was washed with saline, dried with anhydrous sodium sulfate, and then the organic phase was evaporated under reduced pressure to obtain an intermediate product in a yield of 95% or more.

Example 4

The synthetic route for adamantane modified peptidomimetics a22, a24 is as follows:

In a typical reaction, commercially available amino acids (0.5 mmol,1 eq), HOBT (0.6 mmol,81.08mg,1.2eq), HBTU (0.6 mmol,227.54 mg,1.2eq) and DIPEA (1.2 mmol,155.1 mg,2.4eq) were added to DMF of 30mL, dissolved with stirring, and N-Boc-ethylenediamine (0.6 mmol,1.2 eq) was added to react 3 h with stirring at room temperature, and the progress of the reaction was checked using a silica gel reaction plate. After the completion of the reaction, 120 mL saturated saline and 60 mL ethyl acetate were added and washed with shaking, the organic phase was retained, then the organic layer was washed with saline, dried with anhydrous sodium sulfate, and then the organic phase was evaporated under reduced pressure to obtain an intermediate product in a yield of 95% or more.

The intermediate obtained was not further treated, piperidine (1.5 mL), DBU (1.5 mL), tetrahydrofuran (47 mL) were added, the reaction was stirred for 1 hour, the solvent was stripped off under reduced pressure, and the addition of glacial diethyl ether was performed to give the crude product. The obtained crude product was dissolved in DMF solution, 1.2eq adamantanecarboxylic acid and 1.5eq condensing agents HBTU, HOBT and 2eq DIPEA were added to the system and reacted at room temperature for 3h, the progress of the reaction was checked with a silica gel reaction plate, after completion of the reaction, extracted with saturated brine and EA, and the intermediate was obtained after spin-drying.

The intermediate obtained was stirred for 3h without further work-up, trifluoroacetic acid (8 mL), dichloromethane (20 mL) and TIS (200. Mu.L) were added, the solvent was removed under reduced pressure, and the desired product was precipitated by addition of glacial ethyl ether.

Example 5

The synthetic routes of adamantane modified peptidomimetics A2, A4, A6, A8, a10, a12, a14, a16, a17, a20, a27, a30, a32, a34, a36, a38, a40, a42 are as follows:

The intermediate obtained was not further treated, piperidine (1.5 mL), DBU (1.5 mL), tetrahydrofuran (47 mL) were added, the reaction was stirred for 1 hour, the solvent was stripped off under reduced pressure, and the intermediate was precipitated by addition of glacial diethyl ether. The obtained crude product was dissolved in DMF solution, 1.2eq adamantane acetic acid and 1.5eq condensing agents HBTU, HOBT and 2eq DIPEA were added to the system to react for 3h at room temperature, the progress of the reaction was checked with a silica gel reaction plate, and after the completion of the reaction, extracted with saturated brine and EA, and the intermediate was obtained after spin-drying.

The intermediate obtained was stirred for 3h without further work-up, with trifluoroacetic acid (8 mL), dichloromethane (20 mL) and TIS (200 μl), the solvent was removed under reduced pressure, and the target product was precipitated by addition of glacial ethyl ether, and finally the final compound was obtained by further HPLC purification.

The synthesis of adamantane modified peptoid A20 requires quaternary ammonium salt modification of the crude product of the previous step, dissolving the crude product of the previous step in methanol solution, adding a certain amount of MeI and KHCO ₃ to react at room temperature for 72: 72h, adding 120mL of water after solvent evaporation, washing with 60: 60 mL ethyl acetate in a shaking manner to retain an organic phase, washing the organic layer with saline, drying with anhydrous sodium sulfate, and evaporating the organic phase under reduced pressure to obtain the crude product A20.

Example 6

The synthetic route for adamantane modified peptidomimetic a19 is as follows:

In a typical reaction, commercially available Fmoc-Cys (Dpm) -OH (0.5 mmol,1 eq), HOBT (0.6 mmol,81.08mg,1.2eq), HBTU (0.6 mmol,227.54 mg,1.2eq) and DIPEA (1.2 mmol,155.1 mg,2.4eq) were added to 30 mL of DMF and dissolved with stirring, N-Boc-butanediamine (0.6 mmol,1.2 eq) was added and the reaction was stirred at room temperature for 3h and the progress of the reaction was checked using a silica gel reaction plate. After the completion of the reaction, 120 mL saturated saline and 60 mL ethyl acetate were added and washed with shaking, the organic phase was retained, then the organic layer was washed with saline, dried with anhydrous sodium sulfate, and then the organic phase was evaporated under reduced pressure to obtain an intermediate product in a yield of 95% or more.

The intermediate obtained was not further worked up, piperidine (1.5 mL), DBU (1.5 mL), tetrahydrofuran (47 mL) were added, the solvent was removed under reduced pressure and the intermediate precipitated by addition of glacial diethyl ether. The obtained crude product was dissolved in DMF solution, 1.2eq adamantane acetic acid and 1.5eq condensing agents HBTU, HOBT and 2eq DIPEA were added to the system to react for 3h at room temperature, the progress of the reaction was checked with a silica gel reaction plate, and after the completion of the reaction, extracted with saturated brine and EA, and the intermediate was obtained after spin-drying.

EXAMPLE 7 purification preparation of adamantane-modified peptoids

And (3) separating and purifying the adamantane modified peptoid crude products synthesized in the examples 1-6 by a high performance liquid chromatograph. Specifically, the synthesized crude peptide mimetic sample was washed with diethyl ether to precipitate, and then the remaining diethyl ether was removed using a rotary evaporator, followed by dissolution of the precipitate and gradient elution purification using an acetonitrile (0.1% tfa)/water (0.1% tfa) system. And identifying the purified product by mass spectrum and freeze-drying to obtain the adamantane modified peptoid. The synthesized adamantane modified peptoid structure and nuclear magnetism are characterized as follows:

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.31 – 8.23 (m, 3H), 7.88 (dd, J = 51.4, 9.4 Hz, 1H), 7.40 – 7.20 (m, 5H), 4.22 (s, 1H), 3.42 (ddt, J = 15.8, 9.0, 6.9 Hz, 1H), 2.99 (t, J = 7.8 Hz, 2H), 1.96 – 1.88 (m, 2H), 1.85 – 1.77 (m, 2H), 1.65 – 1.54 (m, 4H), 1.46 (d, J = 11.4 Hz, 5H), 1.24 (d, J = 12.2 Hz, 1H), 1.15 (d, J = 11.1 Hz, 1H), 0.93 (d, J = 6.9 Hz, 2H), 0.68 (d, J = 6.9 Hz, 2H).¹³C NMR (101 MHz, DMSO-d₆) δ 167.05, 134.95, 129.51, 128.37, 127.03, 53.41, 52.77, 37.68, 37.24, 36.50, 35.35, 27.69, 13.95. for adamantane modified peptidomimetic A1 Compound molecular weight data theoretical molecular weight C ₂₁H₂₀N₂O [M+H]⁺ = 327.2401, mass Spectrometry molecular weight 327.2401. Compound purity by reverse phase high Performance liquid chromatography (RP-HPLC) was 95.02%.

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.19 (t, J = 5.7 Hz, 1H), 7.97 (d, J = 8.1 Hz, 1H), 7.87 (s, 3H), 7.25 (d, J = 5.8 Hz, 4H), 7.22 – 7.12 (m, 1H), 4.48 (ddd, J = 10.3, 8.1, 4.7 Hz, 1H), 3.33 – 3.24 (m, 2H), 3.03 (dd, J = 13.9, 4.8 Hz, 1H), 2.75 (dd, J = 13.8, 10.4 Hz, 1H), 2.55 (s, 1H), 1.85 – 1.74 (m, 5H), 1.58 (d, J = 12.6 Hz, 3H), 1.49 – 1.35 (m, 7H), 1.26 (dt, J = 12.3, 2.6 Hz, 3H).¹³C NMR (101 MHz, DMSO d₆) δ 172.12, 170.01, 137.89, 129.08, 127.92, 126.14, 54.00, 49.76, 41.81, 40.37, 38.34, 37.22, 36.31, 32.06, 27.93. for adamantane modified peptidomimetic A2 Compound molecular weight data theoretical molecular weight C ₂₃H₃₃N₃O₂ [M+H]⁺ = 384.2635, mass Spectrometry molecular weight 384.3535. Compound purity as determined by reverse phase high Performance liquid chromatography (RP-HPLC) was 100.00%.

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 11.05 (d, J = 2.5 Hz, 1H), 8.15 (d, J = 5.3 Hz, 3H), 8.04 (d, J = 9.4 Hz, 1H), 7.67 (d, J = 7.8 Hz, 1H), 7.35 (d, J = 8.0 Hz, 1H), 7.23 (d, J = 2.4 Hz, 1H), 7.13 – 7.05 (m, 1H), 7.05 – 6.98 (m, 1H), 4.08 (q, J= 6.6Hz, 1H), 3.48 (dt, J = 9.4, 5.7 Hz, 1H), 3.22 (dd, J = 14.4, 7.1 Hz, 1H), 3.04(dd, J = 14.4, 7.9 Hz, 1H), 1.82 – 1.77 (m, 3H), 1.56 (d, J = 12.1 Hz, 3H), 1.43 (d, J = 11.9 Hz, 3H), 1.25 (q, J = 12.3 Hz, 7H), 0.96 (d, J = 6.9 Hz, 3H).¹³C NMR (101 MHz, DMSO d₆) δ 167.68, 136.25, 126.92, 124.64, 121.08, 118.40, 111.40, 107.04, 52.77, 52.61, 37.61, 36.42, 35.34, 27.80, 27.59, 13.92. for adamantane modified peptidomimetic A3 molecular weight data theoretical molecular weight C ₂₃H₃₁N₃O [M+H]⁺ = 366.2566, mass spectrometry molecular weight 366.3206, compound purity 95.37% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 10.84 (d, J = 2.5 Hz, 1H), 8.17 (t, J = 5.8 Hz, 1H), 7.88 – 7.83 (m, 3H), 7.58 (d, J = 7.8 Hz, 1H), 7.31 (d, J = 8.1 Hz, 1H), 7.14 (d, J = 2.4 Hz, 1H), 7.08 – 7.02 (m, 1H), 6.97 (t, J = 7.4 Hz, 1H), 4.49 (ddd, J = 9.5, 7.5, 5.2 Hz, 1H), 3.29 (d, J = 5.9 Hz, 1H), 3.12 (dd, J = 14.6, 5.2 Hz, 1H), 2.92 (dd, J = 14.6, 9.5 Hz, 1H), 2.81 (q, J = 6.4 Hz, 2H), 1.85 (d, J = 12.5 Hz, 1H), 1.80 – 1.76 (m, 4H), 1.56 (d, J = 11.3 Hz, 4H), 1.46 – 1.37 (m, 6H), 1.33 – 1.27 (m, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 172.58, 170.13, 136.11, 127.13, 123.73, 120.76, 118.35, 118.12, 111.20, 109.92, 53.41, 49.70, 41.83, 38.39, 36.34, 32.15, 28.00, 27.94, 27.49. for adamantane modified peptidomimetic A4 molecular weight data theoretical molecular weight C ₂₅H₃₄N₄O₂ [M+H]⁺ = 423.2733, mass spectrometry molecular weight 423.2733, compound purity 97.44% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.04 (q, J = 9.4, 8.1 Hz, 3H), 7.92 (d, J = 9.3 Hz, 1H), 3.65 (q, J = 5.7 Hz, 1H), 3.55 (td, J = 9.1, 6.9 Hz, 2H), 1.95 (q, J = 3.2 Hz, 3H), 1.86 – 1.75 (m, 1H), 1.67 (d, J = 12.0 Hz, 3H), 1.58 (t, J = 12.3 Hz, 4H), 1.49 (dd, J = 13.9, 2.8 Hz, 6H), 1.12 (dtt, J = 18.2, 7.1, 4.1 Hz, 1H), 1.00 – 0.92 (m, 5H), 0.91 – 0.83 (m, 4H).¹³C NMR (101 MHz, DMSO-d₆) δ 167.20, 57.01, 56.40, 53.00, 37.95, 36.53, 35.29, 27.71, 23.76, 14.66, 14.06, 11.01. for adamantane modified peptidomimetic A5 Compound molecular weight data theoretical molecular weight C ₁₈H₃₂N₂O [M+H]⁺ = 293.2965, mass Spectrometry molecular weight 293.3183. Compound purity 96.87% as determined by reverse phase high Performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.18 (t, J = 5.7 Hz, 1H), 7.85 (s, 1H), 7.82 (d, J = 7.9 Hz, 3H), 3.36 – 3.21 (m, 2H), 2.83 (dq, J = 12.7, 6.3 Hz, 2H), 1.97 (d, J = 12.6 Hz, 1H), 1.94 – 1.84 (m, 4H), 1.77 – 1.61 (m, 4H), 1.61 – 1.37 (m, 11H), 1.12 (dt, J = 13.5, 7.7 Hz, 1H), 0.81 (dt, J = 7.4, 4.0 Hz, 7H).¹³C NMR (101 MHz, DMSO-d₆) δ 171.99, 170.39, 57.11, 49.42, 42.01, 38.36, 36.43, 36.19, 35.58, 32.32, 28.01, 24.48, 15.43, 10.71. for adamantane modified peptidomimetic A6 Compound molecular weight data theoretical molecular weight C ₂₀H₃₅N₃O₂ [M+H]⁺ = 350.2703, mass Spectrometry molecular weight 350.3603. Compound purity as determined by reverse phase high Performance liquid chromatography (RP-HPLC) was 100.00%.

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.37 – 8.15 (m, 3H), 8.12 (d, J = 9.2 Hz, 1H), 8.02 (d, J = 9.3 Hz, 1H), 3.99 – 3.91 (m, 1H), 3.54 (dt, J = 9.4, 6.4 Hz, 1H), 2.96 – 2.89 (m, 2H), 1.98 – 1.91 (m, 4H), 1.65 – 1.58 (m, 5H), 1.49 (s, 7H), 0.98 (dd, J = 6.9, 2.9 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 166.03, 54.11, 53.20, 37.83, 36.51, 35.36, 27.70, 25.29, 13.98. for adamantane modified peptidomimetic A7 Compound molecular weight data theoretical molecular weight C ₁₅H₂₆N₁OS [M+H]⁺ = 282.1805, mass Spectrometry molecular weight 283.1805. Compound purity by reverse phase high Performance liquid chromatography (RP-HPLC) was 95.67%.

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.36 – 8.26 (m, 1H), 8.16 (d, J = 8.1 Hz, 1H), 8.06 (s, 3H), 4.31 (td, J = 7.6, 5.3 Hz, 1H), 3.32 (q, J = 6.2 Hz, 2H), 2.91 – 2.65 (m, 4H), 2.39 (t, J = 8.4 Hz, 1H), 1.98 (d, J = 12.7 Hz, 1H), 1.93 – 1.88 (m, 4H), 1.69 – 1.60 (m, 4H), 1.60 – 1.51 (m, 9H).¹³C NMR (101 MHz, DMSO-d₆) δ 170.47, 170.26, 55.17, 49.63, 42.01, 38.32, 36.42, 32.29, 28.02, 25.84. for adamantane modified peptidomimetic A8 molecular weight data theoretical molecular weight C ₁₇H₂₉N₃O₂S [M+H]⁺ = 340.2046, mass spectrometry molecular weight 340.2046, compound purity 95.99% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.19 (d, J = 5.3 Hz, 3H), 7.94 (d, J = 5.7 Hz, 1H), 7.92 (d, J = 6.0 Hz, 3H), 3.84 (s, 7H), 2.74 (dt, J = 11.1, 5.7 Hz, 2H), 1.76 – 1.64 (m, 5H), 1.60 – 1.54 (m, 5H), 1.48 (d, J = 14.5 Hz, 6H), 0.97 (dd, J = 11.1, 6.9 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 167.83, 52.73, 52.03, 38.44, 37.89, 36.54, 35.59, 30.78, 27.67, 26.38, 21.36, 13.96. for adamantane modified peptidomimetic A9 molecular weight data theoretical molecular weight C ₁₈H₃₃N₃O [M+H]⁺ = 308.2657, mass spectrometry molecular weight 308.2657, compound purity 98.75% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.15 (t, J = 5.8 Hz, 1H), 7.94 (d, J = 7.5 Hz, 1H), 7.89 (s, 3H), 7.82 (s, 3H), 4.11 (td, J = 8.5, 5.4 Hz, 1H), 3.33 – 3.25 (m, 2H), 2.84 (s, 2H), 2.74 (p, J = 5.4, 4.6 Hz, 2H), 1.96 – 1.83 (m, 6H), 1.64 (t, J 12.5 Hz, 5H), 1.58 – 1.51 (m, 10H), 1.40 – 1.19 (m, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 172.45, 158.42, 52.45, 49.55, 42.00, 38.62, 38.40, 36.41, 36.30, 32.27, 30.82, 28.00, 26.59, 22.36. for adamantane modified peptidomimetic A10 molecular weight data theoretical molecular weight C ₂₀H₃₆N₄O₂ [M+H] ⁺ = 365.2870, mass spectrometry molecular weight 365.2870, compound purity 99.03% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.15 (t, J = 5.8 Hz, 1H), 7.94 (d, J = 7.5 Hz, 1H), 7.89 (s, 3H), 7.82 (s, 3H), 4.11 (td, J = 8.5, 5.4 Hz, 1H), 3.33 – 3.25 (m, 2H), 2.84 (s, 2H), 2.74 (p, J = 5.4, 4.6 Hz, 2H), 1.96 – 1.83 (m, 6H), 1.64 (t, J = 12.5 Hz, 5H), 1.58 – 1.51 (m, 10H), 1.40 – 1.19 (m, 3H). ¹³C NMR (101 MHz, DMSO-d₆) δ 172.45, 158.42, 52.45, 49.55, 42.00, 38.62, 38.40, 36.41, 36.30, 32.27, 30.82, 28.00, 26.59, 22.36. for adamantane modified peptidomimetic A11 molecular weight data theoretical molecular weight C ₂₈H₃₆N₂OS [M+H] ⁺ = 449.2566, mass spectrometry molecular weight 449.2566, compound purity 95.74% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.16 (t, J = 5.8 Hz, 1H), 7.79 (d, J = 27.7 Hz, 3H), 7.39 – 7.30 (m, 10H), 6.75 – 6.65 (m, 1H), 5.34 (d, J = 9.0 Hz, 2H), 4.38 – 4.20 (m, 2H), 3.35 – 3.24 (m, 8H), 2.83 (q, J = 6.1 Hz, 3H), 2.58 (ddd, J = 16.0, 7.9, 3.4 Hz, 2H), 1.53 (dq, J = 11.2, 3.4 Hz, 4H), 1.42 (p, J = 5.5 Hz, 5H).¹³C NMR (101 MHz, DMSO-d₆) δ 172.22, 171.29, 158.22, 157.91, 156.94, 141.51, 141.32, 128.52, 128.03, 127.08, 53.93, 52.81, 52.59, 44.39, 38.58, 38.29, 36.33, 33.51, 25.24, 24.01. for adamantane modified peptidomimetic A12 molecular weight data theoretical molecular weight C ₃₀H₃₉N₃O₂S [M+H]⁺ = 506.2833, mass spectrometry molecular weight 506.3533, compound purity 98.44% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.31 (s, 3H), 8.18 (d, J = 9.3 Hz, 1H), 3.61 – 3.49 (m, 1H), 2.89 (dd, J = 14.0, 6.3 Hz, 1H), 2.79 (dd, J = 14.0, 7.4 Hz, 1H), 2.14 (s, 3H), 1.93 (t, J = 3.3 Hz, 3H), 1.68 – 1.56 (m, 7H), 1.49 (d, J = 3.6 Hz, 6H), 0.99 (d, J = 6.9 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 166.57, 52.89, 51.30, 37.78, 36.51, 35.69, 34.73, 27.71, 14.92, 13.89. for adamantane modified peptidomimetic A13 molecular weight data theoretical molecular weight C ₁₆H₂₈N₂OS [M+H]⁺ = 297.1962, mass spectrometry molecular weight 297.1962, compound purity 97.24% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.32 (t, J = 5.7 Hz, 1H), 8.06 (d, J = 7.9 Hz, 1H), 7.82 (s, 3H), 7.32 – 7.29 (m, 3H), 4.44 (q, J = 7.5 Hz, 1H), 3.82 – 3.68 (m, 2H), 3.31 (q, J = 6.5 Hz, 2H), 2.85 (q, J = 6.4 Hz, 2H), 2.74 (dd, J = 13.5, 6.5 Hz, 1H), 1.97 – 1.83 (m, 5H), 1.65 (d, J = 12.3 Hz, 3H), 1.62 – 1.48 (m, 9H).¹³C NMR (101 MHz, DMSO-d₆) δ 171.11, 170.20, 51.88, 49.61, 41.98, 38.33, 36.41, 36.39, 35.27, 32.30, 28.02, 14.97. for adamantane modified peptidomimetic A14 molecular weight data theoretical molecular weight C ₁₈H₃₁N₃O₂S [M+H] ⁺ = 354.2172, mass spectrometry molecular weight 354.2172, compound purity 100.00% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.35 (s, 3H), 8.18 (d, J = 9.4 Hz, 1H), 7.39 – 7.24 (m, 5H), 4.03 (td, J = 6.7, 3.6 Hz, 1H), 3.90 – 3.76 (m, 2H), 3.61 – 3.47 (m, 1H), 2.86 – 2.72 (m, 2H), 1.94 (dt, J = 10.2, 3.4 Hz, 3H), 1.67 (d, J = 11.8 Hz, 2H), 1.62 (d, J = 4.7 Hz, 2H), 1.57 (s, 2H), 1.49 (dd, J = 10.3, 5.9 Hz, 7H), 0.99 (dd, J = 11.9, 6.9 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 166.50, 137.78, 128.96, 128.41, 127.03, 53.21, 51.59, 37.76, 36.52, 35.73, 34.97, 32.24, 27.71, 14.02. for adamantane modified peptidomimetic A15 molecular weight data theoretical molecular weight C ₂₂H₃₂N₂OS [M+H]⁺ = 373.2250, mass spectrometry molecular weight 373.2250, compound purity 98.09% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 11.05 (d, J = 2.5 Hz, 1H), 8.15 (d, J = 5.3 Hz, 3H), 8.04 (d, J = 9.4 Hz, 1H), 7.67 (d, J = 7.8 Hz, 1H), 7.35 (d, J = 8.0 Hz, 1H), 7.23 (d, J = 2.4 Hz, 1H), 7.13 – 7.05 (m, 1H), 7.05 – 6.98 (m, 1H), 4.08 (q, J = 6.6 Hz, 1H), 3.48 (dt, J = 9.4, 5.7 Hz, 1H), 3.22 (dd, J = 14.4, 7.1 Hz, 1H), 3.04 (dd, J = 14.4, 7.9 Hz, 1H), 1.82 – 1.77 (m, 3H), 1.56 (d, J = 12.1 Hz, 3H), 1.43 (d, J = 11.9 Hz, 3H), 1.25 (q, J = 12.3 Hz, 7H), 0.96 (d, J = 6.9 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 167.68, 136.25, 126.92, 124.64, 121.08, 118.40, 111.40, 107.04, 52.77, 52.61, 37.61, 36.42, 35.34, 27.80, 27.59, 13.92. for adamantane modified peptidomimetic A16 molecular weight data theoretical molecular weight C ₂₄H₃₅N₃O₂S [M+H]⁺ = 430.2477, mass spectrometry molecular weight 430.2477, compound purity 100.00% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.34 (s, 3H), 8.17 (d, J = 9.3 Hz, 1H), 7.33 – 7.25 (m, 2H), 6.92 – 6.82 (m, 2H), 4.00 (t, J = 6.8 Hz, 1H), 3.78 (s, 2H), 3.72 (s, 3H), 3.54 (dq, J = 8.7, 6.7 Hz, 1H), 2.79 – 2.69 (m, 2H), 1.96 – 1.89 (m, 3H), 1.73 – 1.50 (m, 8H), 1.47 (d, J = 4.6 Hz, 5H), 1.00 (d, J = 6.9 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 166.54, 158.29, 130.13, 129.47, 113.72, 55.03, 52.82, 51.60, 37.76, 36.47, 35.74, 34.36, 32.14, 27.70, 13.92. for adamantane modified peptidomimetic A17 molecular weight data theoretical molecular weight C ₁₆H₂₈N₂OS [M+H]⁺ = 403.2343, mass spectrometry molecular weight 403.2343, compound purity 100.00% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.33 (t, J = 5.7 Hz, 1H), 8.05 (d, J = 7.9 Hz, 1H), 7.93 – 7.83 (m, 3H), 7.27 – 7.19 (m, 2H), 6.90 – 6.82 (m, 2H), 4.43 (td, J = 7.8, 6.5 Hz, 1H), 3.71 (d, J = 12.0 Hz, 6H), 3.37 – 3.27 (m, 2H), 2.86 (h, J = 6.1 Hz, 2H), 2.72 (dd, J = 13.5, 6.5 Hz, 1H), 1.94 (d, J = 12.6 Hz, 1H), 1.90 (dd, J = 6.5, 3.5 Hz, 3H), 1.69 – 1.51 (m, 13H).¹³C NMR (101 MHz, DMSO-d₆) δ 171.01, 170.18, 158.14, 130.00, 129.95, 113.68, 54.98, 51.98, 49.60, 42.00, 38.33, 36.40, 34.40, 32.49, 32.34, 28.03. for adamantane modified peptidomimetic A18 molecular weight data theoretical molecular weight C ₂₅H₃₇N₃O₃S [M+H]⁺ = 460.2588, mass spectrometry molecular weight 460.2558, compound purity 100.00% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.11 (t, J = 5.7 Hz, 1H), 7.97 (d, J = 8.4 Hz, 1H), 7.70 (d, J = 7.6 Hz, 3H), 7.46 – 7.38 (m, 4H), 7.32 (q, J = 7.7 Hz, 4H), 7.27 – 7.20 (m, 2H), 5.36 (s, 1H), 4.48 (q, J = 7.6 Hz, 1H), 3.06 (q, J = 6.5 Hz, 2H), 2.75 (h, J = 6.1 Hz, 2H), 2.59 (dd, J = 13.2, 6.7 Hz, 1H), 2.41 (dd, J = 13.2, 7.8 Hz, 1H), 1.93 – 1.83 (m, 5H), 1.63 (d, J = 12.1 Hz, 4H), 1.53 (d, J = 11.7 Hz, 10H), 1.49 – 1.38 (m, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 170.11, 158.18, 141.34, 128.48, 128.04, 127.07, 52.42, 51.69, 49.61, 41.98, 38.41, 37.89, 36.38, 33.66, 32.30, 28.02, 25.89, 24.33. for adamantane modified peptidomimetic A19 molecular weight data theoretical molecular weight C ₃₂H₄₃N₃O₂S [M+H]⁺ = 534.3155, mass spectrometry molecular weight 534.3955, compound purity 98.61% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 8.45 (t, J = 5.7 Hz, 1H), 8.09 (d, J = 7.9 Hz, 1H), 7.48 – 7.39 (m, 4H), 7.37 – 7.30 (m, 4H), 7.27 – 7.21 (m, 2H), 5.35 (s, 1H), 4.46 (q, J = 7.6 Hz, 1H), 3.50 (d, J = 6.2 Hz, 2H), 3.33 (t, J = 6.4 Hz, 2H), 3.05 (s, 9H), 2.63 (dd, J = 13.4, 6.7 Hz, 1H), 2.42 (dd, J = 13.3, 8.0 Hz, 1H), 1.93 – 1.82 (m, 5H), 1.61 (t, J = 13.0 Hz, 4H), 1.54 (d, J = 6.3 Hz, 9H).¹³C NMR (101 MHz, DMSO-d₆) δ 170.91, 170.08, 141.21, 128.53, 128.00, 127.14, 63.54, 52.59, 52.40, 51.69, 49.58, 41.99, 36.36, 33.32, 33.18, 32.29, 28.00. for adamantane modified peptidomimetic A20 molecular weight data theoretical molecular weight C ₃₃H₄₆N₃O₂S+ [M+H]⁺ = 548.3295, mass spectrometry molecular weight 548.3245, compound purity 99.47% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 6.50 (s, 1H), 3.79 (tt, J = 5.1, 3.5 Hz, 1H), 3.22 (dd, J = 7.8, 5.2 Hz, 1H), 3.08 (dd, J = 7.8, 5.2 Hz, 1H), 2.89 – 2.77 (m, 2H), 2.10 – 2.01 (m, 3H), 1.96 (d, J = 5.1 Hz, 6H), 1.78 (t, J = 6.4 Hz, 1H), 1.65 (t, J = 5.5 Hz, 6H). ¹³C NMR (101 MHz, DMSO-d₆) δ 173.06, 56.44, 51.08, 41.90, 36.29, 30.52, 29.75, 28.75. for adamantane modified peptidomimetic A21 molecular weight data theoretical molecular weight C ₁₃H₂₁N₂OS [M+H]⁺ = 255.1526, mass spectrometry molecular weight 255.1322, compound purity 99.77% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.59 (d, J = 8.1 Hz, 1H), 6.84 (t, J = 4.8 Hz, 1H), 4.45 (dt, J = 8.1, 4.2 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.28 (qdt, J = 14.8, 4.8, 4.0 Hz, 2H), 3.00 (tt, J = 6.3, 4.0 Hz, 2H), 2.88 (dd, J = 6.7, 4.2 Hz, 2H), 2.03 (hept, J = 5.5 Hz, 3H), 1.87 – 1.80 (m, 7H), 1.71 (d, J = 11.4 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 177.65, 173.69, 56.78, 42.27, 41.66, 38.69, 36.22, 30.22, 29.31, 28.37. for adamantane modified peptidomimetic A22 molecular weight data theoretical molecular weight C ₁₆H₂₇N₃O₂S [M+H]⁺ = 326.1897, mass spectrometry molecular weight 326.1823, compound purity 97.17% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.34 – 7.21 (m, 10H), 6.61 (s, 1H), 4.98 (t, J = 0.9 Hz, 1H), 3.94 (dt, J = 5.3, 3.6 Hz, 1H), 3.42 (dd, J = 8.0, 5.2 Hz, 1H), 3.30 (dd, J = 8.1, 5.1 Hz, 1H), 3.01 – 2.89 (m, 2H), 2.10 – 2.01 (m, 3H), 1.96 (d, J = 5.1 Hz, 6H), 1.65 (t, J = 5.4 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 172.01, 141.62, 128.67, 128.02, 127.89, 60.34, 55.04, 51.08, 41.90, 36.29, 34.61, 30.52, 29.75. for adamantane modified peptidomimetic A23 molecular weight data theoretical molecular weight C ₂₆H₃₂N₂OS [M+H]⁺ = 421.2308, mass spectrometry molecular weight 421.2301, compound purity 99.26% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.92 (d, J = 7.8 Hz, 1H), 7.34 – 7.21 (m, 10H), 7.06 (d, J = 9.7 Hz, 1H), 4.99 (t, J = 0.9 Hz, 1H), 4.45 (dt, J = 7.9, 4.3 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.28 (qdt, J = 14.8, 4.8, 4.0 Hz, 2H), 3.11 – 2.96 (m, 4H), 2.02 (dq, J = 11.1, 5.5 Hz, 3H), 1.85 (d, J = 5.2 Hz, 6H), 1.71 (d, J = 11.4 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 177.63, 172.19, 141.65, 128.67, 128.02, 127.89, 60.27, 55.65, 42.27, 41.66, 38.69, 36.22, 33.08, 30.22, 29.31. for adamantane modified peptidomimetic A24 molecular weight data theoretical molecular weight C ₂₉H₃₇N₃O₂S [M+H]⁺ = 492.2679, mass spectrometry molecular weight 492.2329, compound purity 96.16% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 6.72 (t, J = 6.4 Hz, 1H), 3.64 (tt, J = 6.2, 5.3 Hz, 1H), 3.08 (d, J = 6.5 Hz, 2H), 2.90 (tq, J = 6.8, 2.2 Hz, 2H), 2.83 (dd, J = 8.1, 6.2 Hz, 1H), 2.71 (dd, J = 8.1, 6.2 Hz, 1H), 2.51 (t, J = 6.8 Hz, 2H), 2.05 – 1.93 (m, 3H), 1.93 – 1.84 (m, 2H), 1.66 (t, J = 5.7 Hz, 6H), 1.50 (d, J = 5.1 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.95, 53.06, 49.78, 39.85, 39.78, 38.60, 37.97, 37.89, 35.57, 34.04, 30.37, 29.59, 29.54. for adamantane modified peptidomimetic A25 molecular weight data theoretical molecular weight C ₁₅H₂₇N₃O [M+H]⁺ = 266.2227, mass spectrometry molecular weight 266.2322. Purity of compound determined by reversed phase high performance liquid chromatography (RP-HPLC) is 97.23%.

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.34 – 7.21 (m, 10H), 6.74 (t, J = 6.4 Hz, 1H), 4.98 (t, J = 0.9 Hz, 1H), 3.92 (tt, J = 5.7, 4.2 Hz, 1H), 3.30 (dd, J = 7.9, 5.7 Hz, 1H), 3.20 (dd, J = 8.1, 5.7 Hz, 1H), 3.08 (d, J = 6.4 Hz, 2H), 3.04 – 2.91 (m, 2H), 2.05 – 1.95 (m, 3H), 1.66 (d, J = 11.4 Hz, 6H), 1.50 (d, J = 5.1 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 173.67, 141.62, 128.67, 128.02, 127.89, 60.32, 54.22, 49.77, 39.78, 37.89, 35.57, 34.68, 30.37, 29.54. for adamantane modified peptidomimetic A26 molecular weight data theoretical molecular weight C ₂₇H₃₄N₂OS [M+H]⁺ = 435.2465, mass spectrometry molecular weight 435.2411, compound purity 99.71% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.84 (d, J = 7.7 Hz, 1H), 7.05 – 6.99 (m, 3H), 6.75 – 6.69 (m, 2H), 6.14 (s, 1H), 4.43 (dt, J = 7.7, 6.6 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.35 – 3.20 (m, 2H), 3.07 – 3.00 (m, 3H), 3.00 – 2.95 (m, 1H), 2.07 (s, 2H), 2.00 (dtd, J = 10.9, 5.8, 5.0 Hz, 3H), 1.69 – 1.60 (m, 12H).¹³C NMR (101 MHz, DMSO-d₆) δ 173.59, 172.65, 156.46, 130.77, 128.87, 115.72, 55.42, 46.99, 42.27, 41.66, 40.65, 37.89, 37.44, 34.57, 30.45, 29.63. for adamantane modified peptidomimetic A27 molecular weight data theoretical molecular weight C ₂₃H₃₃N₃O₃[M+H]⁺ = 400.2595, mass spectrometry molecular weight 400.2493, compound purity 98.63% as determined by reverse phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.05 (dt, J = 8.6, 1.0 Hz, 2H), 6.75 – 6.69 (m, 2H), 6.38 (d, J = 7.7 Hz, 1H), 6.14 (s, 1H), 3.88 (p, J = 5.9 Hz, 1H), 3.57 (dq, J = 7.5, 5.2 Hz, 1H), 2.89 (dd, J = 5.9, 1.4 Hz, 2H), 2.53 (dd, J = 8.0, 6.0 Hz, 1H), 2.37 (dd, J = 8.0, 5.9 Hz, 1H), 2.02 (dq, J = 10.8, 5.4 Hz, 3H), 1.66 (t, J = 5.5 Hz, 6H), 1.57 (d, J = 5.2 Hz, 6H), 1.03 (d, J = 5.3 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.70, 156.84, 130.70, 127.25, 115.38, 54.93, 54.55, 39.55, 38.76, 37.65, 36.77, 35.29, 16.30. for adamantane modified peptidomimetic A28 molecular weight data theoretical molecular weight C ₂₁H₃₀N₂O₂[M+H]⁺ = 343.2380, mass spectrometry molecular weight 343.2236, compound purity 99.67% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 5.96 (d, J = 7.8 Hz, 1H), 3.57 (dq, J = 7.9, 5.2 Hz, 1H), 3.39 (td, J = 6.4, 5.6 Hz, 1H), 2.97 (dd, J = 7.7, 6.4 Hz, 1H), 2.89 (dd, J = 7.9, 6.4 Hz, 1H), 2.05 – 1.97 (m, 4H), 1.97 – 1.92 (m, 1H), 1.66 (td, J = 5.5, 4.0 Hz, 6H), 1.57 (d, J = 5.2 Hz, 6H), 1.03 (d, J = 5.3 Hz, 3H), 0.92 (d, J = 6.4 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 173.02, 58.32, 54.97, 39.62, 39.55, 38.84, 38.76, 36.77, 35.36, 35.29, 31.44, 18.69, 16.30. for adamantane modified peptidomimetic A29 molecular weight data theoretical molecular weight C ₁₇H₃₀N₂O [M+H]⁺ = 279.2431, mass spectrometry molecular weight 279.2456, compound purity 99.45% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.51 (d, J = 8.1 Hz, 1H), 6.74 (t, J = 4.6 Hz, 1H), 4.27 (dd, J = 8.1, 6.5 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.30 – 3.22 (m, 2H), 3.00 (tt, J = 6.3, 4.0 Hz, 2H), 2.12 – 2.02 (m, 3H), 2.02 – 1.96 (m, 3H), 1.69 – 1.60 (m, 12H), 0.89 (dd, J = 6.5, 2.1 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 173.13, 173.06, 58.61, 47.01, 42.33, 41.66, 40.65, 37.89, 34.57, 30.64, 30.45, 29.63, 18.95. for adamantane modified peptidomimetic A30 molecular weight data theoretical molecular weight C ₁₉H₃₃N₃O₂ [M+H]⁺ = 336.2646, mass spectrometry molecular weight 336.2596, compound purity 98.64% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 6.51 (d, J = 7.5 Hz, 1H), 3.97 (h, J = 5.3 Hz, 1H), 3.57 (dq, J = 7.5, 5.2 Hz, 1H), 3.09 (dd, J = 7.9, 5.5 Hz, 1H), 2.96 (dd, J = 7.9, 5.5 Hz, 1H), 2.02 (dq, J = 10.8, 5.4 Hz, 3H), 1.66 (td, J = 5.5, 4.1 Hz, 6H), 1.57 (d, J = 5.2 Hz, 6H), 1.33 (d, J = 5.1 Hz, 3H), 1.03 (d, J = 5.3 Hz, 3H). ¹³C NMR (101 MHz, DMSO-d₆) δ 174.22, 54.88, 50.47, 39.62, 39.55, 38.84, 38.76, 36.76, 35.36, 35.29, 18.25, 16.29. for adamantane modified peptidomimetic A31 molecular weight data theoretical molecular weight C ₁₅H₂₆N₂O[M+H]⁺ = 251.2118, mass spectrometry molecular weight 251.2165, compound purity 97.31% by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 7.35 (d, J = 7.3 Hz, 1H), 6.94 (t, J = 4.5 Hz, 1H), 4.36 (dq, J = 7.3, 6.1 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.29 – 3.19 (m, 2H), 3.00 (tt, J = 6.3, 4.0 Hz, 2H), 2.00 (ddd, J = 10.9, 5.8, 5.1 Hz, 5H), 1.69 – 1.60 (m, 13H), 1.32 (d, J = 6.0 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 173.17, 172.73, 50.42, 46.96, 42.29, 41.68, 40.65, 37.89, 34.57, 30.45, 29.63, 17.85. for adamantane modified peptidomimetic A32 molecular weight data theoretical molecular weight C ₁₇H₂₉N₃O₂ [M+H]⁺ = 308.2118, mass spectrometry molecular weight 308.2009, compound purity 99.40% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data :¹H NMR (400 MHz, DMSO-d₆) δ 6.34 (d, J = 7.7 Hz, 1H), 3.61 – 3.52 (m, 2H), 2.74 (dd, J = 8.0, 5.4 Hz, 1H), 2.55 (dd, J = 7.9, 5.5 Hz, 1H), 2.02 (dq, J = 10.8, 5.4 Hz, 3H), 1.77 – 1.63 (m, 7H), 1.59 – 1.48 (m, 8H), 1.03 (d, J = 5.3 Hz, 3H), 0.92 (dd, J = 7.1, 1.1 Hz, 6H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.97, 54.94, 52.43, 41.76, 39.62, 39.55, 38.84, 38.76, 36.76, 35.36, 35.29, 25.01, 22.40, 16.30. for adamantane modified peptidomimetic A33 molecular weight data theoretical molecular weight C ₁₈H₃₁N₂O[M+H]⁺ = 293.2587, mass spectrometry molecular weight 293.2519, compound purity 99.35% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data : ¹H NMR (400 MHz, DMSO-d₆) δ 7.38 (d, J = 7.1 Hz, 1H), 6.92 (t, J = 4.9 Hz, 1H), 4.30 – 4.23 (m, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.35 – 3.20 (m, 2H), 3.00 (tt, J = 6.3, 4.0 Hz, 2H), 2.07 (s, 2H), 2.00 (ddd, J = 10.9, 5.8, 5.1 Hz, 3H), 1.69 – 1.49 (m, 15H), 0.91 – 0.83 (m, 6H). ¹³C NMR (101 MHz, DMSO-d₆) δ 174.31, 172.80, 52.93, 46.99, 42.26, 41.68, 40.95, 40.65, 37.89, 34.57, 30.45, 29.63, 24.78, 22.40. for adamantane modified peptidomimetic A34 molecular weight data theoretical molecular weight C ₂₀H₃₅N₂O₂[M+H]⁺ = 350.2802, mass spectrometry molecular weight 350.2749, compound purity 97.25% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 6.26 (d, J = 7.7 Hz, 1H), 3.61 – 3.51 (m, 2H), 3.30 (dd, J = 7.9, 5.1 Hz, 1H), 2.93 (dd, J = 8.1, 5.1 Hz, 1H), 2.61 (dtd, J = 7.3, 5.5, 3.5 Hz, 2H), 2.01 (dt, J = 10.7, 5.4 Hz, 3H), 1.98 – 1.92 (m, 2H), 1.92 – 1.87 (m, 1H), 1.66 (t, J = 5.5 Hz, 6H), 1.57 (s, 6H), 1.03 (d, J = 5.3 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.64, 54.95, 53.39, 39.55, 38.76, 36.76, 35.29, 35.21, 22.43, 16.30. for adamantane modified peptidomimetic A35 molecular weight data theoretical molecular weight C ₁₆H₂₇N₂OS [M+H]⁺ = 297.1995, mass spectrometry molecular weight 297.1976, compound purity 99.67% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 7.91 (d, J = 7.0 Hz, 1H), 6.82 (t, J = 4.9 Hz, 1H), 4.27 (dt, J = 7.0, 4.9 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.28 (qdt, J = 14.7, 4.8, 3.9 Hz, 2H), 3.00 (tt, J = 6.3, 4.0 Hz, 2H), 2.60 (dtd, J = 6.9, 5.8, 3.8 Hz, 2H), 1.69 – 1.60 (m, 12H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.13, 172.77, 53.70, 46.99, 42.26, 41.68, 40.65, 37.89, 34.57, 33.77, 30.45, 29.63, 22.23. for adamantane modified peptidomimetic A36 molecular weight data theoretical molecular weight C ₁₈H₃₀N₃O₂S [M+H]⁺ = 354.2210, mass spectrometry molecular weight 354.2212, compound purity 99.24% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 6.26 (d, J = 7.5 Hz, 1H), 3.64 – 3.53 (m, 2H), 3.14 (dd, J = 7.9, 5.9 Hz, 1H), 3.00 – 2.91 (m, 2H), 2.85 (dd, J = 8.1, 5.9 Hz, 1H), 2.02 (dq, J = 10.8, 5.4 Hz, 3H), 1.80 – 1.72 (m, 4H), 1.66 (td, J = 5.5, 4.0 Hz, 6H), 1.61 – 1.51 (m, 8H), 1.03 (d, J = 5.3 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.76, 54.94, 54.00, 40.27, 39.62, 39.55, 38.84, 38.76, 36.76, 35.36, 35.29, 30.82, 27.67, 16.30. for adamantane modified peptidomimetic A37 molecular weight data theoretical molecular weight C ₁₇H₃₀N₃OS [M+H]⁺ = 294.2540, mass spectrometry molecular weight 294.2543, compound purity 99.34% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 7.82 (d, J = 7.5 Hz, 1H), 6.83 (t, J = 4.9 Hz, 1H), 4.32 – 4.24 (m, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.28 (qdt, J = 14.7, 4.7, 3.9 Hz, 2H), 3.04 – 2.89 (m, 4H), 2.07 (s, 2H), 2.00 (ddd, J = 10.9, 5.8, 5.1 Hz, 3H), 1.88 – 1.68 (m, 6H), 1.67 – 1.60 (m, 12H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.38, 172.77, 54.13, 46.99, 42.26, 41.68, 40.65, 40.48, 37.89, 34.57, 30.45, 29.63, 29.07, 27.11. for adamantane modified peptidomimetic A38 molecular weight data theoretical molecular weight C ₁₉H₃₃N₄O₂S [M+H]⁺ = 251.2755, mass spectrometry molecular weight 251.2613, compound purity 99.23% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 6.26 (d, J = 7.7 Hz, 1H), 3.64 – 3.53 (m, 2H), 2.93 – 2.87 (m, 2H), 2.82 (dd, J = 7.9, 6.0 Hz, 1H), 2.69 (dd, J = 8.0, 6.0 Hz, 1H), 2.51 (t, J = 6.8 Hz, 2H), 2.02 (dq, J = 10.8, 5.4 Hz, 3H), 1.91 (qd, J = 4.8, 3.8 Hz, 2H), 1.66 (td, J = 5.5, 4.0 Hz, 6H), 1.57 (d, J = 5.2 Hz, 6H), 1.03 (d, J = 5.3 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 175.04, 54.94, 52.98, 39.62, 39.55, 38.84, 38.76, 38.60, 36.76, 35.36, 35.29, 34.06, 16.30. for adamantane modified peptidomimetic A39 molecular weight data theoretical molecular weight C ₁₆H₂₈N₃OS[M+H]⁺ = 280.2383, mass spectrometry molecular weight 280.2423, compound purity 99.12% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 7.83 (d, J = 7.7 Hz, 1H), 6.82 (t, J = 4.9 Hz, 1H), 4.21 (dt, J = 7.7, 5.9 Hz, 1H), 4.08 (t, J = 6.3 Hz, 2H), 3.28 (qdt, J = 14.7, 4.8, 3.9 Hz, 2H), 3.04 – 2.91 (m, 4H), 2.80 (q, J = 6.6 Hz, 1H), 2.69 (q, J = 6.5 Hz, 1H), 2.11 – 2.01 (m, 3H), 2.01 – 1.96 (m, 3H), 1.96 – 1.90 (m, 1H), 1.69 – 1.60 (m, 12H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.70, 172.77, 53.36, 46.99, 42.26, 41.68, 40.65, 38.39, 37.89, 34.57, 32.74, 30.45, 29.63. for adamantane modified peptidomimetic A40 molecular weight data theoretical molecular weight C ₁₈H₃₁N₄O₂S [M+H]⁺ = 337.2598, mass spectrometry molecular weight 337.2513, compound purity 99.19% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 6.27 (d, J = 7.5 Hz, 1H), 3.66 – 3.53 (m, 2H), 3.16 (dd, J = 8.4, 5.3 Hz, 1H), 2.95 (td, J = 5.9, 2.9 Hz, 2H), 2.94 – 2.87 (m, 1H), 2.65 (dt, J = 7.3, 6.0 Hz, 1H), 2.58 (dt, J = 7.3, 5.9 Hz, 1H), 2.02 (dq, J = 10.8, 5.4 Hz, 3H), 1.66 (td, J = 5.5, 4.1 Hz, 6H), 1.57 (d, J = 5.2 Hz, 6H), 1.02 (d, J = 5.1 Hz, 3H).¹³C NMR (101 MHz, DMSO-d₆) δ 174.21, 54.93, 53.13, 42.75, 39.62, 39.55, 38.84, 38.76, 36.77, 35.36, 35.29, 16.31. for adamantane modified peptidomimetic A41 molecular weight data theoretical molecular weight C ₁₅H₂₆N₃OS [M+H]⁺ = 266.2227, mass spectrometry molecular weight 266.3213, compound purity 99.38% as determined by reversed phase high performance liquid chromatography (RP-HPLC).

Nuclear magnetic resonance spectroscopy data ：¹H NMR (400 MHz, DMSO-d₆) δ 7.68 (d, J = 7.1 Hz, 1H), 6.96 (t, J = 4.9 Hz, 1H), 4.19 (dt, J = 7.3, 3.7 Hz, 1H), 4.04 (t, J = 6.3 Hz, 2H), 3.35 – 3.20 (m, 2H), 3.04 – 2.85 (m, 6H), 2.07 (s, 2H), 2.00 (ddd, J = 10.9, 5.8, 5.1 Hz, 3H), 1.69 – 1.60 (m, 12H). ¹³C NMR (101 MHz, DMSO-d₆) δ 174.57, 173.07, 52.79, 46.99, 42.27, 41.84, 41.66, 40.72, 40.65, 37.89, 34.57, 30.45, 29.69, 29.63. ¹³C NMR (101 MHz, DMSO-d₆) δ 174.57, 173.07, 52.79, 46.99, 42.27, 41.84, 41.66, 40.72, 40.65, 37.89, 34.57, 30.45, 29.69, 29.63. for adamantane modified peptidomimetic A42 Compound molecular weight data theoretical molecular weight C ₁₇H₂₉N₄O₂S [M+H]⁺ = 323.2442, mass Spectrometry molecular weight 323.2413. Compound purity by reverse phase high Performance liquid chromatography (RP-HPLC) was 99.12%.

Example 8 determination of in vitro antibacterial Activity of adamantane modified peptoids

And (3) performing in-vitro antibacterial activity measurement on the adamantane modified peptoids A1-A42 purified in the example 7. Strains used for the determination of the in vitro antibacterial activity of adamantane-modified peptidomimetics and control antibiotics were standard strains (including E.coli ATCC 25922, C.albicans ATCC 14053), staphylococcus aureus (S. Aureus ATCC 25923, MRSA ATCC 43300), bacillus subtilis ATCC 23875, staphylococcus epidermidis (S. EPIDERMIDIS ATCC 12228), enterococcus faecalis (E. FAECALIS ATCC 19433, VRE ATCC 51299) and enterococcus gallinarum (E. gallinarum ATCC 49573), all from the American type culture Collection.

The Minimum Inhibitory Concentration (MIC) values of the adamantane-modified peptidomimetics and control antibiotics for the tested strains were determined using standard double dilution methods recommended by the american society for clinical and laboratory standards (NCCLS). Briefly, an appropriate amount of bacterial (or fungal) stock was taken into fresh MH/SD medium and the stock was placed on a 37℃shaker and incubated overnight at 180 rpm. And (3) carrying out secondary transfer on the bacterial liquid, and continuously culturing for 4-5 hours in a shaking table to obtain bacteria in the logarithmic growth phase. Then 1X 10 ⁶ CFU/mL of bacterial liquid is added into a 96-well plate, 100 mu L of each well is added, and then 100 mu L of polypeptide (1-100 mu g/mL) with different concentrations twice as high as the final concentration is added into each well in a double dilution mode. The negative control was fresh medium, and three replicates were made for each concentration. After dosing, placing the 96-well plate into a 37 ℃ constant temperature and humidity incubator for culturing for 18-24 hours, and observing the result, wherein the concentration of the cyclopeptide antibiotic in the first transparent hole after the turbid hole is visible by naked eyes is recorded as the minimum antibacterial concentration of the cyclopeptide antibiotic, namely the MIC value of the cyclopeptide antibiotic to the bacterium, and the statistical result is shown in the following table 1:

TABLE 1 minimum inhibitory concentration MIC (μg/mL) of adamantane modified peptidomimetics A1-A42 for test bacteria

。

Example 9 measurement of hemolytic Activity on mammalian erythrocytes (HC ₅₀ > 100. Mu.g/mL)

The purified adamantane-modified peptidomimetics A1, A3, A7, A8, A11, A12, A19, A20, A21, A22, A23, A24, A25, A26, A27 and A36 of example 7 were incubated with mouse erythrocytes, and the hemolytic activity of the cyclopeptide antibiotic was evaluated by detecting the absorbance of the solution OD ₄₉₀ using a microplate reader.

Firstly, the whole blood 1200 rpm of the taken mice is centrifuged to remove supernatant from 5 min, 100% of erythrocytes are collected after PBS is washed, the erythrocytes are diluted to 8% and added into a 96-well plate, a to-be-detected peptoid solution with the concentration of 100 mug/mL is added and then placed into a cell incubator for co-incubation, after 1h, the 96-well plate 1500 rpm is centrifuged to 15 min, and then the supernatant is transferred into another 96-well plate, and OD ₄₉₀ is detected by an enzyme marker. Finally, the hemolysis rate of each peptoid is calculated according to the formula of hemolysis rate (%) = (experimental group OD ₄₉₀ -negative control group OD ₄₉₀)/(positive control group OD ₄₉₀ -negative control group OD ₄₉₀) x 100%.

As shown in FIG. 1, the hemolysis rate of adamantane modified peptoids A19 and A20 was more than 80%, and other peptoids were less toxic to erythrocytes. The hemolytic rate of the adamantane modified peptoid A8 is lower than 5%, and the hemolytic toxicity of A1, A2, A7, A11, A12, A21, A22, A23, A24, A25, A26, A27 and A36 is between 10% and 20%.

Example 10 cytotoxicity assay

Cytotoxicity of the purified adamantane-modified peptidomimetics A1, A3, A7, A8, A11, A12, A19, A20, A21, A22, A23, A24, A25, A26, A27 and A36 of example 7 on mouse fibroblast NIH 3T3 was determined.

Cell viability is defined as the amount of viable cells in a sample. Cytotoxicity assays are commonly used in drug screening to detect whether a test molecule has an effect on cell proliferation or exhibits a direct cytotoxic effect.

The well-living cell suspension was diluted to 5X 10 ⁴ cells/mL and then added to a 96-well plate with 100. Mu.L of the cell suspension per well. Culturing in a cell culture incubator for 24 h. Adding an adamantane modified peptoid solution to be detected, putting the cell culture box into the cell culture box for co-incubation for 24h hours, adding 5 mg/mL of MTT (methyl thiazolyl tetrazolium) 10 mu L into each hole, culturing for 3-5 hours in a dark place, discarding liquid in a 96-well plate, adding 150 mu L of dimethyl sulfoxide (DMSO) into each hole, oscillating for 15min, and measuring absorbance at 570 nm. Cell viability was calculated using the formula viability (%) = experimental OD ₅₇₀/control OD ₅₇₀ x 100%.

As shown in fig. 2, the survival rate of cells after the adamantane modified peptoids a19 and a20 act is lower than 60%, and other peptoids have weak toxicity to mouse fibroblasts. The cell survival rate after the A8 and the A11 are acted is higher than 90%, and the cell survival rate after the A1, the A2, the A7, the A12, the A21, the A22, the A23, the A24, the A25, the A26, the A27 and the A36 are acted is 70% -90%.

Example 11 bactericidal kinetics assay

The effect of the cyclopeptide antibiotic on the growth and proliferation of staphylococcus aureus s. Aureus ATCC 25923 was determined by Colony (CFU) counting, represented by the adamantane modified peptidomimetics A8 and a11 purified in example 7, and then plotted on the abscissa with the time interval as the abscissa and the logarithmic value of colony count per milliliter as the ordinate, to represent the bactericidal kinetics of the cyclopeptide antibiotic. Briefly, staphylococcus aureus at 1.0×10 ⁶ CFU/mL log phase concentration was added to 96-well plates, then added with cyclopeptide antibiotics (final concentration 4×mic), co-cultured at 37 ℃, and after appropriate bacterial solutions were taken out at equal intervals to dilute by appropriate multiples at 0 h, 1/6 h, 1/2 h,1 h,2 h,4 h,6 h,8 h, 100 μl of diluted bacterial solutions were evenly spread on MH solid medium with spreading bars, and colonies were counted after overnight incubation.

Figure 3 shows that at a 4×mic concentration, adamantane modified peptidomimetic A8 was able to kill bacteria within 2 hours and peptidomimetic a11 was able to kill bacteria within 6 hours, all demonstrating the ability to kill bacteria rapidly.

EXAMPLE 12 drug resistance assay

The adamantane modified peptidomimetics A8 and A11 purified in example 7 were selected for the following resistance assays. The potential of the cyclic peptide antibiotics to induce bacterial resistance was evaluated by measuring the minimum inhibitory concentration of the cyclic peptide antibiotics against staphylococcus aureus ATCC 25923 21 consecutive times. Briefly, staphylococcus aureus in log phase was diluted and added to a 96-well microtiter plate, its MIC was determined using a classical double dilution method, and the concentration of the first well where no turbidity was visible was recorded as initial MIC0. Then, the bacterial liquid in 1/2 ⨯ MIC0 well was used as the bacterial liquid for next MIC measurement, and the 1 st MIC was measured by the same method and designated as MIC1. Next, MIC values of the cyclic peptide antibiotics against staphylococcus aureus were continuously measured in the same manner, and were continuously measured for 21 times, which was designated MIC21. Finally, the generation of the resistance of bacteria induced by the cyclopeptide antibiotics is evaluated by plotting the number of times of measurement as an abscissa and the ratio of MIC value to MIC0 value of each measurement as an ordinate. Clinical antibiotics Amoxicillin were used as controls.

As shown in FIG. 4, in the bacterial resistance experiment carried out for 21 days, the MIC value of the adamantane modified peptoid A8 is 6.25-12.5 mug/mL, the MIC value of the adamantane modified peptoid A11 is 3.125-6.25 mug/mL, and the initial MIC is changed by 1-2 times, and the bacterial does not generate resistance.

The initial MIC of the amoxicillin group was 0.16 μg/mL, the MIC value was 8 times the initial value on day 7, the MIC value was 32 times the initial value on day 12, and the MIC value was 250 times the initial value on day 15.

EXAMPLE 13 Effect on bacterial cell membranes

The effect of the peptidomimetic on bacterial cell membrane was evaluated by detecting the disruption of cell membrane potential of staphylococcus aureus ATCC 25923 by adamantane modified peptidomimetic represented by A8 and a11 purified in example 7 and causing PI absorption by staphylococcus aureus.

1. Damage of adamantane modified peptoid to Staphylococcus aureus membrane potential

The destructive effect of adamantane-modified peptidomimetics on Staphylococcus aureus on the membrane potential of Staphylococcus aureus was determined by the DiOC2 (3) fluorescent probe method. Briefly, staphylococcus aureus ATCC 25923 was centrifuged at 5000 rpm for 10 minutes after 18 hours incubation at 37 ℃, the pellet was collected and washed three times with 10mM PBS (pH 7.4) containing 0.1% glucose, then resuspended to od600=0.5. Subsequently, an equal volume of 60. Mu.M DiOC2 (3) solution was added to the bacterial suspension and incubated at 37℃for 15 minutes in the absence of light. Then, bacterial suspensions (50 μl/well) containing DiOC2 (3) were added to 96-well microtiter plates, followed by 50 μl of different concentrations of cyclic peptide antibiotics (ranging from 1 to 8-fold MIC) and incubated for 30 minutes. Finally, fluorescence was detected for each well using a microplate reader (Synergy NEO2, agilent) with excitation wavelength 485 nm and two emission wavelengths 530 nm and 630 nm, respectively. 0.1% Triton X-100 was used as positive control and PBS was used as negative control.

As shown in fig. 5, adamantane-modified peptoids A8 and a11 destroyed the membrane potential of bacteria in a concentration-dependent manner, and were able to completely destroy the membrane potential of bacteria at a concentration of 4×mic.

2. Determination of the damage to the integrity of the bacterial cell membranes by adamantane-modified peptoids A8 and A11

The damage to bacterial cell membrane integrity by adamantane modified peptidomimetics was assessed by measuring the uptake of the fluorescent dye Propidium Iodide (PI) by staphylococcus aureus (ATCC 25923) following the action of a cyclopeptide antibiotic. Briefly, after overnight incubation of staphylococcus aureus at 37 ℃, the bacterial solution was centrifuged at 5000 rpm for 10 min, washed three times with PBS (10 mm, ph=7.4) and suspended to a concentration of 1 x 10 ⁹ CFU/mL. Subsequently, 100. Mu.L of the Staphylococcus aureus suspension was thoroughly mixed with an equal volume of the cyclopeptide antibiotic solution and incubated for 1 hour in a shaker at 37 ℃. Then, 10 μl PI (1 mg/mL) was added and incubated in the dark for 15 minutes for flow cytometry (NovoCyte Quanteon, agilent) analysis. Untreated groups served as negative controls, or PI (10. Mu.M) and Hoechst 33342 (10. Mu.M) were added 10. Mu.L each and incubated in the dark for 15 minutes for fluorescent inverted microscopy.

As shown in FIG. 6, the positive rate of PI detected by flow cytometry after treatment of adamantane modified peptidomimetics A8 and A11 at a concentration of 4 XMIC was greater than 90%, while the positive rate of PI was less than 10% for Staphylococcus aureus after PBS treatment. This suggests that adamantane modified peptidomimetics A8 and a11 are capable of disrupting the cell membrane of bacteria.

As shown in fig. 7, the staphylococcus aureus treated with adamantane modified peptoids A8 and a11 was able to observe a distinct red fluorescence, whereas the staphylococcus aureus treated with PBS was not able to detect a red fluorescence. This suggests that adamantane modified peptidomimetics A8 and a11 are capable of disrupting bacterial cell membranes, leading to PI entry into bacteria.

As shown in fig. 8, after 4×mic of adamantane-modified peptoids A8 and a11 treated staphylococcus aureus were co-incubated, the biological frozen transmission electron microscopy showed that staphylococcus aureus cells in the negative control group (0.9% NaCl) showed intact cytoplasmic membranes, while after treatment with adamantane-modified peptoids A8 and a11, bacterial cell membranes were destroyed and the outflow of the contents occurred. This further suggests that adamantane modified peptidomimetics A8 and a11 exert an antibacterial effect through a membrane disruption mechanism.

EXAMPLE 14 Activity assay for inhibiting Staphylococcus aureus biofilm production

In this example, the adamantane modified peptidomimetics A8 and A11 purified in example 7 were selected for the following measurement.

The formation of a biofilm of the cyclic peptide antibiotic against staphylococcus aureus (ATCC 25923) was determined using the crystal violet method. Briefly, staphylococcus aureus in the log phase with the concentration of 1.0X10 ⁶ CFU/mL is added into a 96-well plate, then adamantane modified peptidomimetic A8 and adamantane modified peptidomimetic A11 to be detected with the gradient concentration of 1 XMIC to 16 XMIC are respectively added, and the mixture is placed in a constant temperature bacterial incubator at 37 ℃ for standing incubation. After 24 hours, the 96-well plate was removed to remove surface plankton bacteria, after washing with PBS, fixation with methanol, staining with crystal violet solution 15 min, and determination of OD ₅₇₀ by dissolving crystal violet in biofilm with 95% ethanol. The biofilm formation inhibition rate (%) = [1- (experimental group OD ₅₇₀ -negative control group OD ₅₇₀)/(positive control group OD 570-negative control group OD ₅₇₀) ]. Times.100% was calculated according to the formula.

As shown in fig. 9, adamantane-modified peptoid A8 was able to inhibit formation of a staphylococcus aureus biofilm by about 50% at a concentration of 2×mic, and was able to completely inhibit formation of a biofilm at a concentration of 2×mic. The peptoid A11 can completely inhibit Staphylococcus aureus biofilm formation at a concentration of 1 XMIC.

EXAMPLE 15 in vivo antibacterial Activity assay

In vivo antibacterial activity assays were performed on the purified adamantane modified peptidomimetics A8 and A11 of example 7. A model of MRSA-infected mice keratitis and mice pneumonia was established and the therapeutic effect of adamantane-modified peptidomimetics A8 and a11 was examined in these animal models and evaluated.

1. Mouse keratitis model

Female Kunming mice were randomly assigned to untreated control, model, adamantane modified peptidomimetics A8, A11 and vancomycin treatment groups when the therapeutic potential of adamantane modified peptidomimetics was determined in the murine model of pneumonia. After anesthesia of mice in the model group, adamantane modified peptidomimetics A8, a11 and vancomycin treated groups, 25 μl of MRSA (ATCC 43300) bacterial suspension with OD ₆₀₀ of 0.35 was injected into the mouse trachea under visual guidance using a nebulizer needle. 2h and 12h post infection mice in the model group received intraperitoneal injection of physiological saline, and the treatment group was treated with 5mg/kg of adamantane modified peptidomimetics A8, A11 and linezolid (5 mg/kg) and vancomycin, respectively. 24 hours after infection, all mice were sacrificed, bacterial colony counts and H & E staining histological examination were collected and performed.

As shown in fig. 10, adamantane modified peptidomimetics A8 and a11 (5 mg/kg) were effective in reducing pulmonary bacterial load (colony loads of 2.30 x 10 ⁶ CFU/mL and 1.77 x 10 ⁶ CFU/mL, p < 0.001), respectively, comparable to vancomycin (5 mg/kg) treatment groups (colony loads of 8.05 x 10 ⁶ CFU/mL, p < 0.001) within 24 hours. H & E staining results show that the pulmonary alveoli of the adamantane modified peptidomimetic A8 and A11 treated groups are intact, no obvious inflammatory cell and capillary congestion is observed, which is similar to the pulmonary characteristics of linezolid and uninfected groups, while pulmonary alveoli wall capillary congestion of the model group can be used for observing inflammatory cell increase, while pulmonary alveoli wall thickening, pulmonary alveoli tissue reduction, capillary congestion of the model group can be used for observing inflammatory cell increase.

2. Model of mouse pneumonia

When the in vivo antibacterial activity of the peptoids was tested in the murine keratitis model, the Kunming mice were randomly divided into a negative control group, an adamantane modified peptoid A8 treatment group, an adamantane modified peptoid A11 treatment group, and a linezolid control group. After anesthetizing mice of the model group, the treatment group, and the linezolid control group, the cornea of the mice was scratched with a needle, and then infected with 10 μl of MRSA bacterial suspension to establish a keratitis model. 12 hours after infection, mice of the adamantane modified peptidomimetics A8, A11 and linezolid control group were treated with 10 μl of 1mg/mL adamantane modified peptidomimetics A8, A11 and linezolid, respectively, in multiple eye drops. Meanwhile, the model group received 10. Mu.L of 0.9% physiological saline each time. 8 hours after treatment, mice were sacrificed and their ocular tissues were collected for bacterial colony counts and H & E staining histological examination.

As shown in fig. 11, the model group showed an apparent load of eyeball bacteria after 8 hours of physiological saline treatment, the average colony load was 2.93×10 ⁷ CFU/mL, while the eyeball colony load after treatment with adamantane modified peptoids A8, a11 and linezolid was significantly reduced, and the average colony loads were 4.83×10 ⁶ CFU/mL、 7.05×10⁶ CFU/mL and 8.05×10 ⁶ CFU/mL, respectively. There was no significant difference (p > 0.5) between the aggregate loading of the adamantane modified peptoids A8 and a11 and the positive control linezolid group. H & E staining results show that the cornea of the model group is defective, a large amount of inflammatory cells are accumulated at the same time, while the adamantane modified peptoids A8, A11 and linezolid are used for treating the cornea, the corneal epithelial cells and basal lamina are complete, and the inflammatory cells are fewer.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. An antimicrobial peptide mimicry based on adamantane modification, characterized in that the antimicrobial peptide mimicry is a pharmaceutically acceptable salt of an adamantane-modified peptide;

The adamantane-modified peptide is selected from any one of the following A1 to A42;

;

The pharmaceutically acceptable salts include salts of inorganic bases, salts of organic bases, salts of basic amino acids, salts of inorganic acids, salts of organic acids, or salts of acidic amino acids.

2. The antimicrobial peptide mimicry as described in claim 1, wherein the inorganic base salt is selected from any one of ammonium salts, alkali metal salts, and alkaline earth metal salts;

The salt of the organic base is a salt of any one of the organic bases selected from cyclohexylamine, benzylamine, octylamine, ethanolamine, diethanolamine, diethylamine, triethylamine, ethylenediamine, morpholine, pyrroline, piperidine, N-ethylpiperidine, N-methylmorpholine, and piperazine.

The salt of the basic amino acid is a salt of any one of lysine, arginine, ornithine, and histidine.

The inorganic acid salt is selected from any one of hydrochloride, bromide, sulfate, phosphate, and phosphate ester;

The salt of the organic acid is selected from any one of acetate, formate, propionate, lactate, citrate, fumarate, maleate, benzoate, tartrate, malate, methane sulfonate, ethane sulfonate, toluene sulfonate, and benzene sulfonate;

The salt of the acidic amino acid is a salt of aspartic acid or glutamic acid.

3. The antimicrobial peptide mimicry according to claim 2, wherein the alkali metal salt is a sodium or potassium salt; and the alkaline earth metal salt is a magnesium or calcium salt.

4. The use of the antimicrobial peptide mimicry according to any one of claims 1 to 3 in the preparation of a medicament for treating bacterial infections.

5. The application as described in claim 4, wherein the dosage form of the drug is selected from any one of oral preparations, injections, and topical preparations.