Deerasirox derivative, nuclide marker and preparation method and application of deferasirox derivative and nuclide marker

Abstract

The invention discloses a deferasirox derivative, a nuclide marker as well as a preparation method and application of the deferasirox derivative. The deferasirox derivative is formed by connecting deferasirox residues, a linker and a marking group in a specific chemical form. The invention also provides a nuclide marker based on the compound structure. The compound and the nuclide marker can be enriched in inflammation or tumor focus tissues, especially can be specifically recognized by bacteria, and can accurately diagnose and locate early bacterial infection. The invention also provides an application of the nuclide marker in distinguishing bacterial infection and aseptic inflammation in living animals, and the nuclide marker has the advantages of simple and easily available marker, good stability, high specificity and the like, and is suitable for industrial production and clinical popularization.

Description

Technical Field

[0001] The present invention relates to the technical field of bacteria-targeted compounds and radiopharmaceuticals, and in particular to a deferasirox derivative, a radionuclide marker, and a preparation method and application thereof. Background Art

[0002] Infections with pathogenic bacteria are responsible for significant morbidity and mortality and therefore pose a major threat to human health. This situation is exacerbated by the rise of antimicrobial resistance, which has rendered existing treatments ineffective, while the pipeline of new antibiotics capable of breaking resistance remains scarce. Timely and accurate detection and localization of the infecting pathogen is essential to avoid unnecessary antibiotic use and to find appropriate, potentially life-saving treatments.

[0003] Positive bacterial culture from the suspected site (tissue and / or blood) is currently the gold standard for diagnosing specific bacterial infections. This approach has many limitations: (a) it can be invasive; (b) it cannot determine the extent of dissemination of the infection; (c) it lacks sensitivity, often resulting in negative results; (d) it is often identified only when it has reached the systemic stage; and (e) the time required to obtain results often leads to complications, including death. Molecular imaging can achieve specific, sensitive, and site-specific imaging of infection, especially radiotracer-based single-emission computed tomography (SPECT) and positron emission tomography (PET). Many nonspecific radiotracers have been used clinically to image infection. These probes (including [ 18 F]fluorodeoxyglucose ([ 18 F]FDG),[ 68 Ga] metabolite ([ 68 Ga]-Cirtrate)) targets secondary effects of infection, such as increased blood flow and vascular permeability, endothelial cell activation, or polymorphonuclear cell migration. However, it cannot distinguish bacterial infection from sterile inflammation.

[0004] Therefore, the development of bacteria-specific targeted molecular probes to distinguish between bacterial infection and sterile inflammation is a scientific problem that needs to be solved urgently. Recently, the development of pathogen-specific tracers has focused on specific bacterial pathways, including carbohydrate metabolism, bacterial folate biosynthesis, and bacterial-specific iron transport systems, bacterial cell wall components and selective binders, and substrates and antimicrobial peptides for intracellular bacterial proteins. However, no bacteria-specific targeted molecular probe has been approved for clinical use, and there is still room for optimization and improvement in probe sensitivity and pharmacokinetic properties.

[0005] Ferric ions (Fe 3+) is an essential micronutrient for the survival and replication of bacteria and fungi. It is involved in bacterial growth and biofilm formation. Bacteria and fungi secrete specific chelators, called siderophores, to capture Fe from the surrounding environment. 3+ , and the resulting Fe 3+ The complex is very stable and can be recognized, absorbed and internalized by the active transport proteins of bacteria, so the concentration of iron ions is high at the site of bacterial infection. 4-[3,5-bis(2-hydroxyphenyl)-1,2,4-triazol-1-yl]benzoic acid (deferasirox) is an FDA-approved Fe 3+ Complexing groups are used to treat iron overload. Recent studies have shown that deferasirox has significant antibacterial and antifungal activity. Its main mechanism of action is to compete for Fe in bacterial iron carriers. 3+ To inhibit the formation of bacterial cell wall and biofilm. Among the existing bacteria-targeted radioactive imaging agents, there is no molecular imaging probe constructed with deferasirox as the parent core structure and used for in vivo imaging. Summary of the invention

[0006] To overcome the above problems, the present invention uses deferasirox as a lead compound, obtains deferasirox derivatives and radionuclide markers thereof through structural optimization, and provides support for bacterial infection diagnosis through medical imaging, which helps to clinically distinguish bacterial infection from sterile inflammation, further reduce the abuse of antibiotics, and achieve the goal of precision medicine.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] The present invention provides a Deferasirox derivative, the structural formula of which is: R1-R2-R3;

[0009] Among them, R1 is

[0010] R2 is a linker selected from Linker Group 1 or Linker Group 2;

[0011] The linking group 1 is selected from any one of the following structures:

[0012]

[0013] Wherein, n and m are independently integers between 0 and 10; in the above structural formula, the left wavy line connects R1, and the right wavy line connects R3.

[0014] The linking group 2 is selected from any one of the following structures:

[0015]

[0016] Wherein, x and y are independently integers between 0 and 10; in the above structural formula, the left wavy line connects R1, and the right wavy line connects R3.

[0017] L1 and L2 in the linking group 1 and the linking group 2 can be independently selected to be present or absent. For ease of understanding, an example is provided here to illustrate that when L1 does not exist, the -NH- connected to L1 is directly connected to R1; when L2 does not exist, -CO- is directly connected to -OH to form a carboxyl group.

[0018] When L1 is present, L1 can be independently selected from any one or a combination of the following amino acid fragments:

[0019]

[0020] Wherein, a, b and t are independently integers between 0 and 10; in the above structural formula, the imino terminal (-NH-) is connected to R1. When L1 is a combination of several fragments in the above amino acid fragments, the specific combination is: the carbonyl terminal (-CO-) of one amino acid fragment is connected to the imino terminal (-NH-) of another amino acid fragment, and the connection is cyclically connected to form a multi-fragment L1, and the groups to be linked at both ends of L1 are the imino terminal (-NH-) and the carbonyl terminal (-CO-), and the imino terminal (-NH-) is connected to R1.

[0021] When L2 is present, L2 can be independently selected from any one or a combination of the following amino acid fragments:

[0022]

[0023] Wherein, a, b and t are independently integers between 0 and 10; the carbonyl end (-CO-) in the above structural formula is connected to the hydroxyl end (-OH) in the first structural formula of linking group 1 and linking group 2. When L2 is a combination of several fragments in the above amino acid fragments, the specific combination method is: the carbonyl end (-CO-) of an amino acid fragment is connected to the imino end (-NH-) of another amino acid fragment, and the connection is cyclically connected to form a multi-fragment L2, and the groups to be linked at both ends of L2 are the imino end (-NH-) and the carbonyl end (-CO-), wherein the carbonyl end (-CO-) is connected to the hydroxyl end (-OH) in the first structural formula of linking group 1 and linking group 2.

[0024] R3 is a labeling group. When R2 is a linking group 1, R3 is selected from any one of a chelating structure 1 and a fluorescent group;

[0025] The chelate structure 1 comprises:

[0026]

[0027]

[0028] The fluorescent group includes:

[0029]

[0030] When R2 is a linking group 2, R3 is selected from any one of the following chelating structures 2:

[0031]

[0032] As a possible embodiment, further, when R1 in Formula I is When R3 is a different chelating structure and R2 is a different linker, the Deferasirox derivative includes the following structure:

[0033]

[0034]

[0035]

[0036]

[0037]

[0038] Based on the above, the present invention provides a method for preparing a Deferasirox derivative, which is as follows:

[0039] When R2 is linking group 1, the method for preparing the deferasirox derivative is method 1 or method 2;

[0040] The method 1 comprises the following steps:

[0041] Activating the carboxyl group of compound 1 to form compound 2 with a carboxyl activated ester;

[0042] Compound 2 is subjected to a first substitution reaction with compound 3 having an A1 protecting group to obtain compound 4;

[0043] The compound 4 is subjected to a deprotection reaction of the A1 protecting group to generate a compound 5;

[0044] Using an R3 active compound with an activated ester group, anhydride group or isothiocyanate group to carry out a second substitution reaction with compound 5 to obtain the deferasirox derivative;

[0045] The structural formulas of compounds 1 to 5 are as follows:

[0046]

[0047] The method 2 comprises the following steps:

[0048] A third substitution reaction is carried out using an R3 active compound having an activated ester group, anhydride group or isothiocyanate group and a compound 6 having an A2 protective group to obtain a compound 7;

[0049] The compound 7 is subjected to a deprotection reaction of the A2 protecting group to generate a compound 8;

[0050] Performing a fourth substitution reaction on compound 2 and compound 8 to obtain the deferasirox derivative;

[0051] The structural formulas of compounds 6 to 8 are as follows:

[0052]

[0053] The structure of the R3 active compound with an activated ester group, anhydride group or isothiocyanate group includes:

[0054]

[0055]

[0056] When R2 is linking group 2, the method for preparing the deferasirox derivative comprises the following steps:

[0057] The R3 active compound with a maleimide fragment is reacted with the compound 9 with a thiol group to obtain the compound 10;

[0058] Reacting compound 2 with compound 10 to obtain the deferasirox derivative;

[0059] The structural formulas of compounds 9 to 10 are as follows:

[0060]

[0061] The structure of the R3 active compound with maleimide fragment is shown below:

[0062]

[0063] The A1 protecting group and the A2 protecting group are selected from any one of a Boc protecting group, a DDE protecting group or a Fmoc protecting group.

[0064] Based on the above, the present invention also provides a nuclide-labeled deferasirox derivative, the structural formula of which is: R1-R2-R4, wherein R4 is a nuclide labeling group;

[0065] The nuclide-labeled deferasirox derivative R1-R2-R4 is obtained by a coordination reaction between the R3 chelating structure in the above-mentioned deferasirox derivative R1-R2-R3 and the nuclide.

[0066] Preferably, the nuclides include 18 F. 43 Sc, 44 Sc, 47 Sc, 51 Cr, 55 Co. 57 Co. 62 Cu, 64 Cu, 67 Cu, 67 Ga, 68 Ga, 72 As, 72 Se, 89 Zr, 86 Y. 89 Sr. 86 Y. 90 Y. 97 Such as 99m Tc, 105 Rh, 101m Rh, 109 Pd, 111 In, 119 Sb, 128 8. 139 La, 140 La, 142 Pr, 149 Pm, 149 Tb, 151 Tb, 151 Eu, 153 Eu, 169 Eu, 153 Sm, 152 Gd, 153 Gd, 157 Gd, 159 Gd, 161 Tb, 165 Dy, 166 Ho, 169 2. 175 Yb, 177 Lu, 186 Re, 188 Re, 197 Hg, 198 Au, 201 Tl, 203 Pb, 211 At 212 Pb, 212 Bi, 213 Bi, 223 Ra, 227 Th and 225 At least one of Ac.

[0067] Based on the above, the present invention also provides a method for preparing a radionuclide-labeled deferasirox derivative, which is prepared by a wet method or a freeze-drying method;

[0068] The wet preparation comprises the following steps:

[0069] Dissolving the deferasirox derivative and / or its pharmaceutically acceptable form in a solvent; then adding a radionuclide-containing solution, and reacting at room temperature to 110° C. for 10 to 30 minutes to obtain a radionuclide-labeled deferasirox derivative solution;

[0070] The freeze-drying preparation steps are as follows:

[0071] The deferasirox derivative and / or its pharmaceutically acceptable form is dissolved in a solvent, divided into freeze-drying containers, and sealed into freeze-dried medicine boxes after freeze-drying; a solvent is added to the freeze-dried medicine box to dissolve, and then a radionuclide-containing solution is added, and the reaction is carried out at room temperature to 110° C. for 10 to 30 minutes to obtain a radionuclide-labeled deferasirox derivative solution.

[0072] Furthermore, the pharmaceutically acceptable forms of the deferasirox derivatives include salts, stereoisomers, racemates, hydrates and solvates.

[0073] The present invention also provides a pharmaceutical composition, comprising an active ingredient and a pharmaceutically acceptable excipient;

[0074] The active components include the deferasirox derivatives and pharmaceutically acceptable forms thereof, and the radionuclide-labeled deferasirox derivatives and pharmaceutically acceptable forms thereof.

[0075] Furthermore, the pharmaceutically acceptable forms of the deferasirox derivative include salts, stereoisomers, racemates, hydrates and solvates;

[0076] The pharmaceutically acceptable forms of the nuclide-labeled deferasirox derivative include salts, stereoisomers, racemates, hydrates and solvates.

[0077] The present invention also proposes the use of the above-mentioned deferasirox derivatives and their pharmaceutically acceptable forms, the above-mentioned radionuclide-labeled deferasirox derivatives and their pharmaceutically acceptable forms, and the above-mentioned pharmaceutical compositions in the preparation of diagnostic and therapeutic agents or drugs for human or animal diseases. Furthermore, the diseases include tumors and their metastases, inflammation, and bacterial infections.

[0078] Among them, the diagnostic and therapeutic reagent or diagnostic and therapeutic drug can be used to distinguish between bacterial infection and aseptic inflammation sites; the diagnostic and therapeutic reagent or diagnostic and therapeutic drug is prepared into an injection and administered by intravenous injection; and medical imaging is used to provide support for the diagnosis of bacterial infection.

[0079] The beneficial effects of the present invention are as follows:

[0080] 1) The present invention creatively proposes to use the clinically used iron-removing agent 4-[3,5-bis(2-hydroxyphenyl)-1,2,4-triazol-1-yl]benzoic acid (deferasirox) as a broad-spectrum bacterial-specific recognition molecule, and on this basis, structural modification, optimization and radionuclide labeling are carried out to obtain a molecular imaging probe with excellent performance and suitable in vivo pharmacokinetic properties.

[0081] 2) The present invention proposes a type of nuclide-labeled deferasirox derivatives, whose coordination groups have the characteristics of strong labeling ability, short labeling time, high labeling yield, etc., which are conducive to commercial application and clinical promotion.

[0082] 3) The radionuclide-labeled deferasirox derivatives provided by the present invention can effectively detect Escherichia coli and Staphylococcus aureus infection areas in a mammalian model of bacterial infection, and effectively distinguish between live bacterial infection and sterile inflammation, providing an effective reference for clinical bacterial inflammation diagnosis, which is conducive to reducing the abuse of antibiotics and meets the needs of today's precision medicine.

[0083] 4) The Deferasirox derivative designed by the present invention introduces linking units such as amino acids between the targeting group and the coordination structure, which can increase the distance between the targeting group and the coordination structure to avoid mutual influence. At the same time, the linking structure of the present invention provides a good basis for regulating the lipid solubility of the molecule, which can improve the pharmacokinetic properties of the complex, accelerate its clearance rate in non-target tissues, increase the target / non-target ratio, enhance the affinity between the ligand and the receptor, and improve the lesion uptake of the radionuclide-labeled Deferasirox derivative, so that the imaging is clearer, and a better diagnostic effect is obtained, so that the application scope of the radionuclide-labeled Deferasirox derivative of the present invention is effectively expanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0085] Figure 1 It is the mass spectrum of the intermediate 1 of the compound in the present invention.

[0086] Figure 2 It is the mass spectrum of the compound intermediate 2 in the present invention.

[0087] Figure 3 It is the mass spectrum of the compound intermediate 3 in the present invention.

[0088] Figure 4 It is the NMR image of the intermediate 3 of the compound in the present invention.

[0089] Figure 5 It is the mass spectrum of the compound DFC2D in the present invention.

[0090] Figure 6 It is the mass spectrum of the compound DFC2F in the present invention.

[0091] Figure 7 It is the mass spectrum of the compound DFY1D in the present invention.

[0092] Figure 8 It is the mass spectrum of the compound DFA2D in the present invention.

[0093] Fig. 9 HPLC spectra of DFC2D, DFY1D and DFA2D.

[0094] Fig.10 for[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 HPLC spectrum of Ga]Ga-DFA2D.

[0095] Fig.11 DFX, DFC2D, DFY1D and DFA2D with different concentrations of Fe 3+ UV absorption change trend after complexation.

[0096] Fig.12 for[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 HPLC characterization of the stability of Ga]Ga-DFA2D in physiological saline and serum.

[0097] Fig.13 for[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 Uptake of Ga]Ga-DFA2D in Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and inactivated bacteria.

[0098] Fig.14 For DFC2F in Escherichia coli (E. coli) and transporter knockout E. coli (E. coli △

[0099] EntA / B) Bacterial fluorescence images.

[0100] Fig.15for[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 60-minute MicroPET imaging of Ga]Ga-DFA2D in the mouse acute muscle inflammation (right upper limb) caused by Staphylococcus aureus and LPS-induced sterile inflammation (left upper limb) models, dynamic time-uptake curves of the infection site and major organs.

[0101] Fig.16 for[ 68 Static MicroPET imaging of Ga]Ga-DFY1D in the mouse acute muscle inflammation (right upper limb) caused by Staphylococcus aureus or Escherichia coli and LPS-induced sterile inflammation (left upper limb) models, uptake of infection sites and major organs, and HE staining of isolated tissues.

[0102] Fig.17 for[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 Biodistribution results and target / non-target ratio of Ga]Ga-DFA3D at 30 minutes in the mouse acute muscle inflammation (right upper limb) induced by Staphylococcus aureus and LPS-induced sterile inflammation (left upper limb) models. DETAILED DESCRIPTION

[0103] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0104] Preparation Example 1: Preparation of Deferasirox Derivative DFC2D

[0105] The synthetic route of DFC2D is as follows:

[0106]

[0107] The specific steps include:

[0108] 1) Synthesis of intermediate 1

[0109] 4-[3,5-bis(2-hydroxyphenyl)-1,2,4-triazol-1-yl]benzoic acid, dicyclohexylcarbodiimide (DCC) and N-hydroxysuccinimide (NHS) were dissolved in an appropriate amount of N,N-dimethylformamide (DMF) solution at a molar feed ratio of 1:2.5:2, and reacted at room temperature overnight. The reaction progress was monitored by TLC. After the reaction was completed, the solvent was dried and the crude product was purified by silica gel column to obtain intermediate 1. The mass spectrum of intermediate 1 is shown in the attached figure. Figure 1 Shown: C 25 H 18 N4O6, theoretical molecular weight 470.12, mass-to-charge ratio (M / Z): [M+H] + 471.07.

[0110] 2) Synthesis of Intermediate 2

[0111] Intermediate 1 and compound, N-tert-butyloxycarbonyl-1,2-ethylenediamine and N,N-diisopropylethylamine (DIPEA) were dissolved in DMF solution at a molar ratio of 1:2:2, and reacted at room temperature overnight. The reaction progress was monitored by TLC. After the reaction was completed, the solvent was dried and the crude product was purified by silica gel column to obtain intermediate 2. The mass spectrum of intermediate 2 is shown in the attached figure. Figure 2 Shown: C 28 H 29 N5O5, theoretical molecular weight 515.22, mass-to-charge ratio (M / Z): [M+H] + 516.23.

[0112] 3) Synthesis of Intermediate 3

[0113] An appropriate amount of intermediate 2 was dissolved in methanol in a reaction flask, and then an appropriate amount of hydrochloric acid / dioxane mixed solution was slowly added to the reaction flask under ice bath conditions. The reaction solution was subjected to a reaction at room temperature to remove the amino protecting group, and the reaction was stirred until the reaction was complete. The solvent was removed under reduced pressure, and the target product compound intermediate 3 was purified by silica gel column. The mass spectrum and NMR of intermediate 3 are shown in the attached figures. Figure 3 and attached Figure 4 Shown: C 23 H 21 N5O3, theoretical molecular weight 415.16, mass-to-charge ratio (M / Z): [M+H] + 416.17.

[0114] 4) Synthesis of DFC2D

[0115] Intermediate 3 and DOTA-NHS were dissolved in an appropriate amount of DMF according to a molar ratio of 1:1.5, and triethylamine was added. The mixture was reacted at 50°C for 4 hours. After the reaction, an appropriate amount of hydrochloric acid was added to acidify the mixture and then purified by high performance liquid chromatography (HPLC). The mobile phase conditions were as follows: semi-preparative column (250×10mm, 5μm, Thermo), phase A: water + 0.1% trifluoroacetic acid (TFA), phase B: acetonitrile + 0.1% TFA. Gradient elution conditions: 0-5min: 20%-28% phase B; 5-15min: 36% phase B; 15-20min: 36%-49% B; 20-25min: 49%-95% B; 25-40min: 20% phase B, flow rate: 3mL / min, UV wavelength: 254nm. The purified solution was dried in vacuo to obtain the target product. The mass spectrum of DFC2D is shown in the attached figure. Figure 5 Shown: C 39 H 47 N9O 10 , Theoretical molecular weight 801.34, mass-to-charge ratio (M / Z): [M+H] + :802.27. HPLC identification chart is attached Fig. 9 As shown in A, the chemical purity is greater than 95%.

[0116] Preparation Example 2: Preparation of Deferasirox Derivative DFC2F

[0117] The synthetic route of DFC2F is as follows:

[0118]

[0119] According to the preparation method of DFC2D, the corresponding deferasirox derivative DFC2F was obtained by replacing DOTA-NHS with FITC-SCN. The mass spectrum of DFC2F is shown in the attached figure. Figure 6 As shown:

[0120] C 44 H 32 The theoretical molecular weight of N6O8S is 804.20, and the mass-to-charge ratio (M / Z): [M+H]: 805.17.

[0121] Preparation Example 3: Preparation of Deferasirox Derivative DFY1D

[0122] The synthetic route of DFY1D is as follows:

[0123]

[0124] DFX-NHS and polypeptide fragment Y1D were dissolved in an appropriate amount of DMF solution at a molar ratio of 1:1.5, and triethylamine was added. The mixture was reacted at 50°C for 4 hours. After the reaction, an appropriate amount of hydrochloric acid was added for acidification and then purified by high performance liquid chromatography (HPLC). The mobile phase conditions were: semi-preparative column (250×10mm, 5μm, Thermo), phase A: water + 0.1% trifluoroacetic acid (TFA), phase B: acetonitrile + 0.1% TFA.

[0125] Gradient elution conditions: 0-25min: 20%-95% B phase: 20.1-25min: 95% B; 25.1-30min: 20% B phase, flow rate: 3mL / min, UV wavelength: 254nm. The purified solution was vacuum dried to obtain the target product. The mass spectrum of DFY1D is shown in the attached figure. Figure 7 Shown: DFY1D:C 49 H 61 N 11 O 16 Theoretical molecular weight 1059.43, mass-to-charge ratio (M / Z): [M+H] 1060.10. HPLC identification chart as attached Fig. 9 As shown in B, the chemical purity is greater than 95%.

[0126] Preparation Example 4: Preparation of Deferasirox Derivative DFA2D

[0127] The DFA2D synthesis route is as follows:

[0128]

[0129] According to the preparation method of DFY1D, the corresponding deferasirox derivative DFA2D was obtained by replacing the polypeptide fragment Y1D with A2D. The mass spectrum of DFA2D is shown in the attached figure. Figure 8 Shown: DFA2D:C 55 H 12 N 68 O 21 Theoretical molecular weight 1232.46, mass-to-charge ratio (M / Z): [M+H] + 1233.44. HPLC identification chart is attached Fig. 9 As shown in C, the chemical purity is greater than 95%.

[0130] Preparation Example 5: 68 Preparation of Ga-labeled Deferasirox Derivatives

[0131] 68 The Ga nuclide labeling process is as follows:

[0132] Wet method: about 37~3700MBq 68GaCl3 hydrochloric acid solution (eluted from the gallium germanium generator) is added to a centrifuge tube containing 0.5-2 mL acetic acid-acetate solution of DFC2D, DFY1D or DFA2D (20-200 μg), placed at room temperature to 100°C for reaction for 20 minutes, then cooled to room temperature, diluted with physiological saline or water for injection, and sterile filtered to obtain the labeled compound injection.

[0133] Lyophilization method: a certain amount of buffer and about 37-3700MBq 68 GaCl3 hydrochloric acid solution (eluted from the gallium germanium generator) is added to the freeze-dried medicine box containing DFC2D, DFY1D or DFA2D (20-200 μg), mixed and dissolved, placed at room temperature to 100°C for reaction for 20 minutes, then cooled to room temperature, diluted with physiological saline or water for injection, and sterile filtered to obtain the labeled compound injection.

[0134] If the radiochemical purity is less than 95%, purification is required. The purification steps are as follows: Take a Sep-Pak C18 separation column and activate it by eluting it with 10 mL of anhydrous ethanol and 10 mL of water. Dilute the labeled solution with 10 mL of water and load it onto the separation column. Rinse the separation column with water to remove unreacted 68 Ga ions, and then washed with ethanol solution to obtain 68 The Ga-labeled complex is purified by blowing nitrogen to remove the organic solvent, and then diluted with physiological saline and sterile filtered to obtain the labeled compound injection.

[0135] As attached Fig.10 As shown, 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D or [ 68 Ga]Ga-DFA2D was sampled for HPLC analysis and identification. The HPLC system was as follows: reverse phase C18 analytical column (4.6×250 mm), elution gradient: 0-15 minutes: 20% acetonitrile (0.1% TFA) and 80% water (0.1% TFA) increased to 85% acetonitrile (0.1% TFA) and 15% water (0.1% TFA), 15-20 minutes 85% acetonitrile (0.1% TFA) and 15% water (0.1% TFA) changed to 20% acetonitrile (0.1% TFA) and 80% water (0.1% TFA), flow rate was 1 mL / min. The retention time of the radiolabeled target complex was about 11.91 minutes ([ 68 Ga]Ga-DFC2D), 10.47 minutes ([ 68 Ga]Ga-DFY1D), 11.02 minutes ([ 68 Ga]Ga-DFA2D), with a radiochemical purity greater than 95%.

[0136] Example 1: Fe3+ Complexation experiment

[0137] Deferasirox (DFX), DFC2D, DFY1D and DFA2D compounds were dissolved in an appropriate amount of DMSO to obtain a concentration of 1 mM, and then diluted with deionized water to 15 μM. FeCl3 was diluted with water and prepared to concentrations of 15, 10, 5, and 2.5 μM. Equal volumes of compounds were incubated with FeCl3 solution at 37°C for 3 hours. After the incubation, the UV absorption was measured.

[0138] As attached Fig.11 As shown in the figure, the UV absorption peaks and change trends of DFC2D, DFY1D and DFA2D after complexing with iron ions are similar to those of DFX, proving that these compounds can complex with Fe 3+ Effective complexation.

[0139] Example 2: In vitro stability test

[0140] Will[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D or [ 68 Ga]Ga-DFA2D was placed in physiological saline medium at room temperature for different periods of time, and samples were taken for analysis by HPLC.

[0141] Will[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D or [ 68 Ga]Ga-DFA2D was incubated with serum at room temperature for different time periods, acetonitrile was added to remove protein, the supernatant solution was centrifuged and sampled for analysis by HPLC. 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 The HPLC identification results of the physiological saline and in vitro serum stability of Ga]Ga-DFA2D are shown in the attached Fig.12 As shown, it shows that it still maintains a high stability (>95%) in physiological saline or in vitro serum system for 2 hours.

[0142] Example 3: Determination of lipid-water distribution coefficient (logP)

[0143] 100 μL of the diluted radionuclide-labeled deferasirox derivative was added to a centrifuge tube containing a mixture of 0.9 mL PBS and 1 mL n-octanol. After vortexing for 3 minutes, the tube was centrifuged at 9000 rpm for 5 minutes. 100 μL of liquid was taken from each of the aqueous phase and the n-octanol phase and the radioactivity was counted by a γ-counter. The experiment was repeated three times and the average value was taken. The logP calculation formula is:

[0144] P=I有机相 / I 水相

[0145] Among them, I 有机相 represents the radioactive count measured in the organic phase, I 水相 Represents the radioactive count measured in the aqueous phase. By calculation, the lipid-water distribution coefficient of each radiolabeled targeting probe is finally determined. The results are shown in Table 1 below. The measured labeled compounds are hydrophilic.

[0146] Table 1

[0147] Labeled compounds LogP <![CDATA[[ 68 Ga]Ga-DFC2D]]> -1.39 <![CDATA[[ 68 Ga]Ga-DFY1D]]> -2.06 <![CDATA[[ 68 Ga]Ga-DFA2D]]> -2.69

[0148] Example 4: Bacterial targeting specificity verification

[0149] The concentration is about 37 kBq / mL [ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D or [ 68 Ga]Ga-DFA2D was incubated with Escherichia coli (E.coli), Staphylococcus aureus (S.aureus) and inactivated bacteria (HK), and the incubation was terminated at different time points (15, 30, 60, and 90 minutes). The free probe solution was removed and washed three times with pre-cooled saline. Finally, the counts were measured on a γ counter. Fig.13 As shown, the probe can be specifically recognized by live bacteria, while inactivated bacteria cannot take up the probe, with a statistically significant difference ***P<0.001.

[0150] The deferasirox analog (DFC2F) coupled with the fluorescent dye FITC was co-incubated with normal E. coli and E. coli with iron transport receptor knockout (ΔENA / B). Fig.14 It can be seen that the wild-type E. coli emits green fluorescence due to the uptake of DFC2F, while the E. coli with the transport receptor knocked out does not have the ability to uptake DFC2F, which further proves that Deferasirox is a bacteria-specific recognition molecule.

[0151] Example 5: MicroPET / CT imaging of acute muscle inflammation model mice

[0152] Six-week-old female Balb / c mice (weighing about 20 g) were selected and 100 μL of bacteria (10 -7 CFU), and an appropriate amount of LPS was injected into the left upper limb. About 9.25MBq[ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D or [ 68Ga]Ga-DFA2D, MicroPET imaging was performed at different time points and regions of interest (ROI) were delineated on the whole-body decay-corrected images obtained by scanning, and the probe distribution values ​​were calculated.

[0153] As attached Fig.15 As shown, the present invention provides 68 Ga-labeled Deferasirox Derivatives [ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 Ga]Ga-DFA2D exhibits different metabolic patterns in mice. 68 Ga]Ga-DFC2D is metabolized by the liver and kidneys, and the radioactive signal is high in the kidneys. 68 Ga]Ga-DFA2D is mainly metabolized by the kidneys, but radioactive signals are present at the site of bacterial infection. 68 Ga]Ga-DFY1D has obvious uptake at the bacterial infection site, less uptake at the sterility verification site or other normal tissues, and a high ratio of target to non-target. At 30 minutes after the radioactive probe injection, [ 68 Ga]Ga-DFC2D, [ 68 Ga]Ga-DFY1D and [ 68 The uptake of Ga]Ga-DFA2D at the infection site of Staphylococcus aureus was 3.40±0.13, 4.45±0.28 and 3.20±0.07%ID / g, respectively.

[0154] As attached Fig.16 As shown in [ 68 At the 30-minute time point of Ga]Ga-DFY1D imaging, the probe uptake at the sites of Staphylococcus aureus and Escherichia coli infection was 4.75%ID / g and 2.83%ID / g, respectively, the muscle uptake was 0.61%ID / g, and the uptake at the site of sterile inflammation was 1.22%ID / g. The ratios of the bacterial infection site to the sterile inflammation site were 3.89 (Staphylococcus aureus / sterile myositis) and 2.32 (Escherichia coli / sterile myositis), respectively, while the ratios of the bacterial infection site to normal muscle were 7.79 (Staphylococcus aureus / normal muscle) and 4.64 (Escherichia coli / normal muscle).

[0155] Comprehensive attachment Fig.15 and Fig.16 As shown, 68 Ga]Ga-DFY1D has good pharmacokinetic properties and a high target-to-non-target ratio, and can diagnose bacterial infections in vivo and effectively distinguish between bacterial infections and aseptic inflammation.

[0156] Example 6: Biodistribution experiment in muscle inflammation model mice

[0157] Six-week-old female Balb / c mice (weighing about 20 g) were selected and 100 μL of bacteria (10 -7 CFU), and an appropriate amount of Freund's adjuvant LPS was injected into the left upper limb. About 0.74MBq of radionuclide-labeled Deferasirox derivatives were injected through the tail vein of mice. 45 minutes after the injection, the mice were decapitated and killed (3 mice). The blood, brain, heart, liver, lung, kidney, intestine, spleen, muscle, bone and other organs and tissues of interest were taken, weighed and measured for radioactivity counts. The results were expressed as the percentage of uptake dose per gram of tissue or organ (%ID / g). Fig.17 As shown, similar to the results of PET imaging, the probe [ 68 Ga]Ga-DFY1D had the highest uptake at the site of bacterial infection, a high target to non-target ratio, and low uptake in non-target organs.

[0158] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A deferasirox derivative, characterized in that: The structural formula of the Deferasirox derivative is: R1-R2-R3; Among them, R1 is R2 is a linker selected from Linker Group 1 or Linker Group 2; The linking group 1 is selected from any one of the following structures: Wherein, n and m are independently integers between 0 and 10; The linking group 2 is selected from any one of the following structures: Wherein, x and y are independently integers between 0 and 10; L1 and L2 in the linking group 1 and the linking group 2 can be independently selected to be present or absent; When L1 is present, L1 can be independently selected from any one or a combination of the following amino acid fragments: Wherein, a, b and t are independently integers between 0 and 10; When L2 is present, L2 can be independently selected from any one or a combination of the following amino acid fragments: Wherein, a, b and t are independently integers between 0 and 10; R3 is a labeling group. When R2 is a linking group 1, R3 is selected from any one of a chelating structure 1 and a fluorescent group; The chelate structure 1 comprises: The fluorescent group includes: When R2 is a linking group 2, R3 is selected from any one of the following chelating structures 2:

2. A method for preparing the deferasirox derivative according to claim 1, characterized in that: The preparation method is as follows: When R2 is linking group 1, the method for preparing the deferasirox derivative is method 1 or method 2; The method 1 comprises the following steps: Activating the carboxyl group of compound 1 to form compound 2 with a carboxyl activated ester; Compound 2 is subjected to a first substitution reaction with compound 3 having an A1 protecting group to obtain compound 4; The compound 4 is subjected to a deprotection reaction of the A1 protecting group to generate a compound 5; Using an R3 active compound with an activated ester group, anhydride group or isothiocyanate group to carry out a second substitution reaction with compound 5 to obtain the deferasirox derivative; The structural formulas of compounds 1 to 5 are as follows: The method 2 comprises the following steps: A third substitution reaction is carried out using an R3 active compound having an activated ester group, anhydride group or isothiocyanate group and a compound 6 having an A2 protective group to obtain a compound 7; The compound 7 is subjected to a deprotection reaction of the A2 protecting group to generate a compound 8; Performing a fourth substitution reaction on compound 2 and compound 8 to obtain the deferasirox derivative; The structural formulas of compounds 6 to 8 are as follows: The structure of the R3 active compound with an activated ester group, anhydride group or isothiocyanate group includes: When R2 is linking group 2, the method for preparing the deferasirox derivative comprises the following steps: The R3 active compound with a maleimide fragment is reacted with the compound 9 with a thiol group to obtain the compound 10; Reacting compound 2 with compound 10 to obtain the deferasirox derivative; The structural formulas of compounds 9 to 10 are as follows: The structure of the R3 active compound with maleimide fragment is shown below: The A1 protecting group and the A2 protecting group are selected from any one of a Boc protecting group, a DDE protecting group or a Fmoc protecting group.

3. A radionuclide-labeled deferasirox derivative, characterized in that: Its structural formula is: R1-R2-R4, wherein R4 is a nuclide labeling group; The nuclide-labeled deferasirox derivative R1-R2-R4 is obtained by a coordination reaction between the R3 chelate structure in the deferasirox derivative R1-R2-R3 as claimed in claim 1 and the nuclide.

4. The nuclide-labeled deferasirox derivative according to claim 3, characterized in that: The nuclides include 18 F. 43 Sc, 44 Sc, 47 Sc, 51 Cr, 55 Co. 57 Co. 62 Cu, 64 Cu, 67 Cu, 67 Ga, 68 Ga, 72 As, 72 Se, 89 Zr, 86 Y. 89 Sr. 86 Y. 90 Y. 97 Such as 99m Tc, 105 Rh, 101m Rh, 109 Pd, 111 In, 119 Sb, 128 8. 139 La, 140 La, 142 Pr, 149 Pm, 149 Tb, 151 Tb, 151 Eu, 153 Eu, 169 Eu, 153 Sm, 152 Gd, 153 Gd, 157 Gd, 159 Gd, 161 Tb, 165 Dy, 166 Ho, 169 2. 175 Yb, 177 Lu, 186 Re, 188 Re, 197 Hg, 198 Au, 201 Tl, 203 Pb, 211 At 212 Pb, 212 Bi, 213 Bi, 223 Ra, 227 Th and 225 At least one of Ac.

5. A method for preparing a nuclide-labeled deferasirox derivative as claimed in claim 3 or 4, characterized in that: Prepared by wet method or freeze-drying method; The wet preparation comprises the following steps: Dissolving the deferasirox derivative and / or its pharmaceutically acceptable form as claimed in claim 1 in a solvent; then adding a solution containing a nuclide, and reacting at room temperature to 110° C. for 10 to 30 minutes to obtain a nuclide-labeled deferasirox derivative solution; The freeze-drying preparation steps are as follows: The deferasirox derivative and / or its pharmaceutically acceptable form as claimed in claim 1 is dissolved in a solvent, divided into freeze-drying containers, and sealed into freeze-dried medicine boxes after freeze-drying; a solvent is added to the freeze-dried medicine box to dissolve, and then a radionuclide-containing solution is added, and the reaction is carried out at room temperature to 110° C. for 10 to 30 minutes; and a radionuclide-labeled deferasirox derivative solution is obtained.

6. The method for preparing the nuclide-labeled deferasirox derivative according to claim 5, characterized in that: The pharmaceutically acceptable forms of the deferasirox derivatives include salts, stereoisomers, racemates, hydrates and solvates.

7. A pharmaceutical composition, characterized in that comprising active ingredients and pharmaceutically acceptable excipients; The active ingredients include the deferasirox derivatives and pharmaceutically acceptable forms thereof as described in claim 1, and the radionuclide-labeled deferasirox derivatives and pharmaceutically acceptable forms thereof as described in claim 3 or 4.

8. The pharmaceutical composition according to claim 7, characterized in that The pharmaceutically acceptable forms of the deferasirox derivatives include salts, stereoisomers, racemates, hydrates and solvates; The pharmaceutically acceptable forms of the nuclide-labeled deferasirox derivative include salts, stereoisomers, racemates, hydrates and solvates.

9. Use of the deferasirox derivatives and pharmaceutically acceptable forms thereof as described in claim 1, the radionuclide-labeled deferasirox derivatives and pharmaceutically acceptable forms thereof as described in claim 3 or 4, and the pharmaceutical composition as described in claim 7 or 8 in the preparation of diagnostic and therapeutic reagents or drugs for human or animal diseases.

10. The use according to claim 9, characterized in that: The diseases include tumors and their metastases, inflammation, and bacterial infections.

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