A Her2-targeted nuclide probe and its preparation method and application

Abstract

The present invention provides a Her2-targeted nuclide probe and a preparation method and application thereof, and relates to the technical field of nuclide probes. The Her2-targeted nuclide probe comprises a compound shown in formula I labeled with a radionuclide. The Her2-targeted nuclide probe of the present invention can be used as a diagnostic and therapeutic agent in lesions with high expression of Her2 protein in humans or animals, in particular as a tumor imaging agent and a radionuclide therapeutic drug. In animal experiments, the radioactive complex of the present invention has a high tumor / muscle ratio and has good application prospects. Formula I.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclide probes, and in particular to a Her2-targeted nuclide probe and a preparation method and application thereof. Background Art

[0002] Human epidermal growth factor receptor 2 (Her2) has become an attractive biomarker for imaging and treatment of solid tumors due to its upregulated expression in cancer cells. Although many radiopharmaceuticals have been developed for use in radiopharmaceutical therapies, most suffer from insufficient tumor uptake, insufficient tumor residence time, or off-target accumulation in healthy tissues, indicating the need for further improvement. To address this issue, fluorescence imaging methods have attracted widespread attention due to their high selectivity and sensitivity, relatively low cost, and non-invasiveness.

[0003] Lapatinib is an orally active drug used to treat breast cancer and other solid tumors. It is a dual tyrosine kinase inhibitor that interrupts the Her2 and epidermal growth factor receptor pathways, inhibits cell proliferation, and induces apoptosis of tumor cells. It is used to treat patients with advanced or metastatic breast cancer whose tumors overexpress Her2.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a Her2-targeted radionuclide probe and its preparation method and application. The present invention uses a strategy of enhancing the target affinity of chemical probes, utilizes the structural selectivity relationship of lapatinib, uses a covalent method to optimize the parent compound, obtains a new Her2-targeted radioactive ligand, and uses it for PET imaging. From its design, synthesis, and in vitro and in vivo evaluation, the Her2-targeted radionuclide probe exhibits superior properties to previous candidate drugs.

[0006] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0007] In a first aspect, the present invention provides a Her2-targeted nuclide probe, wherein the Her2-targeted nuclide probe comprises a compound of formula 1 labeled with a radionuclide:

[0008]

[0009] Formula 1;

[0010] in,

[0011] The L group is selected from NH or C=O;

[0012] The Y group is selected from any one of the following groups, The attachment site of the representative group:

[0013] ;

[0014] n is a positive integer selected from 1 to 10.

[0015] Preferably, the Her2 targeting nuclide probe includes a compound of formula I labeled with a radionuclide, including any one of the following compounds:

[0016]

[0017]

[0018] .

[0019] Preferably, the radionuclides include 68 Ga, 64 Cu, 86 Y. 89 Zr, 90 Y. 111 In, 123 I or 124 Any one of I, preferably 68 Ga.

[0020] In a second aspect, the present invention provides a method for preparing a Her2 targeting nuclide probe as described in the first aspect, the preparation method comprising:

[0021] (1) Lapatinib and compound PG-L-PEG 2n -COOH undergoes condensation reaction to obtain compound A; wherein the reaction formula is as follows:

[0022] ;

[0023] Wherein, PG represents a protecting group of a carboxyl group or an amino group, the L group is selected from NH or C=O, and n is selected from a positive integer between 1 and 10;

[0024] (2) Compound A is subjected to deprotection treatment to obtain compound B; wherein the reaction formula is as follows:

[0025] ;

[0026] Wherein, PG represents a protecting group of a carboxyl group or an amino group, the L group is selected from NH or C=O, and the L' group is selected from -NH 2 or -COOH, n is selected from a positive integer between 1 and 10;

[0027] (3) Compound B and a chelating agent are subjected to a condensation reaction, followed by a deprotection treatment or without a deprotection treatment, to obtain a compound represented by Formula I; wherein the reaction formula is as follows:

[0028] ;

[0029] Wherein, the chelating agent is selected from , or ;

[0030] (4) Radioactively labeling the compound represented by the formula I with a radioactive nuclide to obtain the Her2-targeting radionuclide probe.

[0031] Preferably, in step (1), the lapatinib and the compound PG-L-PEG 2n The molar ratio of -COOH is (0.5~2):1.

[0032] Preferably, the PG is a protecting group for a carboxyl group, and the protecting group for a carboxyl group is selected from t-Bu; the PG is a protecting group for an amino group, and the protecting group for an amino group is selected from Boc.

[0033] Preferably, in step (1), the temperature of the condensation reaction is 30-40° C., and the time of the condensation reaction is 12-24 h.

[0034] Preferably, in step (1), the condensation reaction is carried out in a solvent selected from dimethyl sulfoxide and / or N,N -Dimethylformamide.

[0035] Preferably, in step (1), the condensation reaction is carried out under a protective gas atmosphere, and the protective gas is selected from nitrogen.

[0036] Preferably, in step (1), the condensation reaction is carried out in the presence of a condensing agent, and the condensing agent is selected from dipyrrolidino ( N -succinimidyloxy)carbonium hexafluorophosphate.

[0037] Preferably, in step (1), the PG-L-PEG 2n The molar ratio of -COOH to the condensing agent is 1:(1.2~2).

[0038] Preferably, in step (1), the condensation reaction is carried out in the presence of a base selected from N,N -Diisopropylethylamine.

[0039] Preferably, in step (1), the PG-L-PEG 2n The molar ratio of -COOH to base is 1:(0.5~5).

[0040] Preferably, in step (2), the reagent used for the deprotection treatment is trifluoroacetic acid.

[0041] Preferably, in step (2), the temperature of the deprotection treatment is 30-40° C., and the time of the deprotection treatment is 1-3 h.

[0042] Preferably, in step (3), the molar ratio of compound B to chelating agent is (0.5-2):1.

[0043] Preferably, in step (3), the temperature of the condensation reaction is 30-40° C., and the time of the condensation reaction is 12-24 h.

[0044] Preferably, in step (3), the condensation reaction is carried out in a solvent selected from dimethyl sulfoxide and / or N,N -Dimethylformamide.

[0045] Preferably, in step (3), the condensation reaction is carried out under a protective gas atmosphere, and the protective gas is selected from nitrogen.

[0046] Preferably, in step (3), the condensation reaction is carried out in the presence of a condensing agent, and the condensing agent is selected from dipyrrolidino ( N -succinimidyloxy)carbonium hexafluorophosphate.

[0047] Preferably, in step (3), the molar ratio of compound B to the condensing agent is 1:(1.2-2).

[0048] Preferably, in step (3), the condensation reaction is carried out in the presence of a base selected from N,N -Diisopropylethylamine.

[0049] Preferably, in step (3), the molar ratio of compound B to base is 1:(0.5-5).

[0050] Preferably, in step (3), the reagent used for the deprotection treatment is trifluoroacetic acid.

[0051] Preferably, in step (3), the temperature of the deprotection treatment is 30-40° C., and the time of the deprotection treatment is 1-3 h.

[0052] Preferably, in step (4), the radioactive labeling comprises the following steps:

[0053] The sodium acetate solution, the compound solution represented by Formula I and the radioactive nuclide solution are mixed and reacted to obtain the Her2 targeting nuclide probe.

[0054] Preferably, the volume ratio of the sodium acetate solution to the radionuclide solution is 1:1.

[0055] Preferably, the concentration of the sodium acetate solution is 1-3 M and the pH is 4.

[0056] Preferably, the concentration of the compound solution represented by formula I is 5×10 -6 M.

[0057] Preferably, the radioactivity of the radionuclide solution is 1-10 mCi.

[0058] Preferably, in step (4), the temperature of the radioactive labeling is 85-95° C., and the time of the radioactive labeling is 5-20 min.

[0059] In a third aspect, the present invention provides a use of the Her2 targeting radionuclide probe or its racemate, stereoisomer, or pharmaceutically acceptable salt as described in the first aspect in the preparation of an agent for tumor imaging.

[0060] Wherein, the tumor includes any one of liver cancer tumor, pancreatic cancer tumor, colon cancer tumor, gastric cancer tumor, breast cancer tumor or head and neck cancer tumor.

[0061] In a fourth aspect, the present invention provides a use of the Her2-targeted radionuclide probe or its racemate, stereoisomer, or pharmaceutically acceptable salt as described in the first aspect in the preparation of a reagent for identifying Her2-overexpressing tumors.

[0062] Compared with the prior art, the present invention has the following beneficial effects:

[0063] (1) The present invention uses an organic total synthesis method to synthesize a series of Her2-targeted nuclide probes, and uses a PEG group to connect lapatinib with a chelating agent ligand of a specific structure, which can not only further improve its water solubility and enable it to be quickly cleared in normal tissues, but also quickly achieve a tumor-to-background signal ratio (TBR>1.5) that meets clinical needs;

[0064] (2) The series of Her2-targeted radionuclide probes synthesized by the present invention have good active targeting effects in identifying Her2-overexpressing tumors and have great development potential in the fields of tumor surgery and medical cell labeling. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0066] Figure 1 Provided for Example 1 68 HPLC chromatogram of Ga-LA-PEG2-NOTA.

[0067] Figure 2 Provided for Example 1 68 Mass spectrum of Ga-LA-PEG2-NOTA.

[0068] Figure 3 Provided for Example 2 68 High performance liquid chromatogram of Ga-LA-PEG2-DOTA.

[0069] Figure 4 Provided for Example 2 68 Mass spectrum of Ga-LA-PEG2-DOTA.

[0070] Figure 5 The Her2 targeting nuclide probe provided in Example 1 68 Liver tumor-specific targeting effect of Ga-LA-PEG2-NOTA. DETAILED DESCRIPTION

[0071] Unless otherwise defined herein, scientific and technical terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meaning and scope of the terms should be clear, however, in the case of any potential ambiguity, the definitions provided herein take precedence over any dictionary or external definitions. In this application, unless otherwise stated, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-limiting.

[0072] It should be noted that specific details are described in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0073] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0074] In a first aspect, the present invention provides a Her2-targeted nuclide probe, wherein the Her2-targeted nuclide probe comprises a compound of formula 1 labeled with a radionuclide:

[0075]

[0076] Formula 1;

[0077] in,

[0078] The L group is selected from NH or C=O;

[0079] The Y group is selected from any one of the following groups, The attachment site of the representative group:

[0080] ;

[0081] n is a positive integer selected from 1 to 10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and more preferably 2 to 4.

[0082] In the present invention, a new type of nuclide probe with the ability to target Her2 is designed and synthesized, namely, radionuclide-labeled LA-PEG-Y. Using lapatinib as a recognition group, PEG terminal modification is performed on the Her2 inhibitor, and PEG is connected to the chelating agent Y (NOTA, DOTA, DFO) to construct a new type of nuclide probe with the ability to target Her2, which can be specifically targeted for identifying Her2 overexpressing tumors. The nuclide probe obtained by the present invention can specifically identify Her2 overexpressing tumors and can be quickly cleared in normal tissues, thereby quickly achieving a tumor-to-background signal ratio (TBR>1.5) that meets clinical needs, and is used for preoperative tumor PET imaging.

[0083] Among them, lapatinib is an orally active drug used to treat breast cancer and other solid tumors. It is a dual tyrosine kinase inhibitor that interrupts the Her2 and epidermal growth factor receptor pathways. It is used to treat patients with advanced or metastatic breast cancer whose tumors overexpress Her2. It remains selective after being combined with a chelator. Lapatinib combined with a chelator shows significant targeting ability to Her2-overexpressing cancer cells but not normal cells, which has research value and can be used for the development of specific targeted radionuclide probes.

[0084] As an optional embodiment, when the L group is selected from NH, the Y group is selected from or .

[0085] As an optional embodiment, when the L group is selected from NH, C=O, the Y group .

[0086] As an optional embodiment, the Her2 targeting nuclide probe includes a compound of formula I labeled with a radionuclide, including any one of the following compounds:

[0087]

[0088]

[0089] .

[0090] As an optional embodiment, the radionuclide comprises 68 Ga, 64 Cu, 86 Y. 89 Zr, 90 Y. 111 In, 123 I or 124 Any one of I, preferably 68 Ga.

[0091] As a preferred embodiment, the radionuclide is 68 Ga.

[0092] In a second aspect, the present invention provides a method for preparing a Her2 targeting nuclide probe as described in the first aspect, the preparation method comprising:

[0093] (1) Lapatinib and compound PG-L-PEG 2n -COOH undergoes condensation reaction to obtain compound A; wherein the reaction formula is as follows:

[0094] ;

[0095] Wherein, PG represents a protecting group of a carboxyl group or an amino group, the L group is selected from NH or C=O, and n is selected from a positive integer between 1 and 10;

[0096] (2) Compound A is subjected to deprotection treatment to obtain compound B; wherein the reaction formula is as follows:

[0097] ;

[0098] Wherein, PG represents a protecting group of a carboxyl group or an amino group, the L group is selected from NH or C=O, and the L' group is selected from -NH 2 or -COOH, n is selected from a positive integer between 1 and 10;

[0099] (3) Compound B and a chelating agent are subjected to a condensation reaction, followed by a deprotection treatment or without a deprotection treatment, to obtain a compound represented by Formula I; wherein the reaction formula is as follows:

[0100] ;

[0101] Wherein, the chelating agent is selected from , or ;

[0102] (4) Radioactively labeling the compound represented by the formula I with a radioactive nuclide to obtain the Her2-targeting radionuclide probe.

[0103] As an optional embodiment, the preparation method of the Her2 targeting nuclide probe comprises:

[0104] (1) Lapatinib and Boc-NH-PEG 2n -COOH undergoes condensation reaction to obtain compound A; wherein the reaction formula is as follows:

[0105] ;

[0106] (2) Compound A is subjected to deprotection treatment to obtain compound B; wherein the reaction formula is as follows:

[0107] ;

[0108] (3) Compound B and chelating agent Y-bis(tBu)ester are subjected to condensation reaction and then deprotection treatment to obtain a compound represented by formula I; wherein the reaction formula is as follows:

[0109] ;

[0110] Wherein, the chelating agent is selected from or .

[0111] As an optional embodiment, in step (1), the lapatinib and the compound PG-L-PEG 2nThe molar ratio of -COOH is (0.5~2):1, for example, it can be 1:1, 1:1.2, 1:1.25, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, etc.

[0112] As an optional embodiment, the PG is a carboxyl protecting group, and the carboxyl protecting group is selected from t-Bu (tert-butyl); the PG is an amino protecting group, and the amino protecting group is selected from Boc (tert-butyloxycarbonyl).

[0113] As an optional embodiment, in step (1), the temperature of the condensation reaction is 30-40°C, for example, it can be 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, etc., and the time of the condensation reaction is 12-24 h, for example, it can be 12 h, 14 h, 15 h, 16 h, 18 h, 20 h, 22 h, 24 h, etc.

[0114] As an optional embodiment, in step (1), the condensation reaction is carried out in a solvent selected from dimethyl sulfoxide and / or N,N -Dimethylformamide.

[0115] As an optional embodiment, in step (1), the condensation reaction is carried out under a protective gas atmosphere, and the protective gas is selected from nitrogen.

[0116] As an optional embodiment, in step (1), the condensation reaction is carried out in the presence of a condensation agent, and the condensation agent is selected from dipyrrolidino ( N -succinimidyloxy)carbonium hexafluorophosphate.

[0117] As an optional embodiment, in step (1), the PG-L-PEG 2n The molar ratio of -COOH to the condensing agent is 1:(1.2~2), for example, it can be 1:1.2, 1:1.25, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, etc.

[0118] As an optional embodiment, in step (1), the condensation reaction is carried out in the presence of a base selected from N,N -Diisopropylethylamine.

[0119] As an optional embodiment, in step (1), the PG-L-PEG 2nThe molar ratio of -COOH to the base is 1:(0.5~5), for example, it can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, etc.

[0120] As an optional embodiment, in step (1), after the condensation reaction is completed, a post-treatment step is also included:

[0121] The reaction solution obtained after the reaction in step (1) is extracted with a mixed solution of water and dichloromethane, and the lower dichloromethane phase is taken and spin-dried to obtain the compound A.

[0122] As an optional embodiment, in the mixed liquid, the volume ratio of water to dichloromethane is 1:(0.5~2), for example, it can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.85, 1:0.9, 1:0.95, 1:1, 1:1.05, 1:1.1, 1:1.15, 1:1.2, 1:1.4, 1:1.6, 1:1.8, 1:2, etc.

[0123] As an optional embodiment, in step (2), the reagent used for the deprotection treatment is trifluoroacetic acid.

[0124] As an optional embodiment, in step (2), the deprotection treatment includes: using trifluoroacetic acid and stirring, and spinning the trifluoroacetic acid to dryness to obtain the compound B.

[0125] As an optional embodiment, in step (2), the temperature of the deprotection treatment is 30-40°C, for example, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, etc., and the time of the deprotection treatment is 1-3 h, for example, 1 h, 1.2 h, 1.4 h, 1.6 h, 1.8 h, 2 h, 2.2 h, 2.4 h, 2.6 h, 2.8 h, 3 h, etc.

[0126] As an optional embodiment, in step (3), the molar ratio of compound B to the chelating agent is (0.5-2):1, for example, it can be 0.5:1, 0.6:1, 0.8:1, 1:1, 1.2:1, 1.4:1, 1.5:1, 1.6:1, 1.8:1, 2:1, etc.

[0127] As an optional embodiment, in step (3), the temperature of the condensation reaction is 30-40°C, for example, it can be 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, etc., and the time of the condensation reaction is 12-24 h, for example, it can be 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, 24 h, etc.

[0128] As an optional embodiment, in step (3), the condensation reaction is carried out in a solvent selected from dimethyl sulfoxide and / or N,N -Dimethylformamide.

[0129] As an optional embodiment, in step (3), the condensation reaction is carried out under a protective gas atmosphere, and the protective gas is selected from nitrogen.

[0130] As an optional embodiment, in step (3), the condensation reaction is carried out in the presence of a condensation agent, and the condensation agent is selected from dipyrrolidino ( N -succinimidyloxy)carbonium hexafluorophosphate.

[0131] As an optional embodiment, in step (3), the molar ratio of compound B to the condensing agent is 1:(1.2-2), for example, it can be 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, etc.

[0132] As an optional embodiment, in step (3), the condensation reaction is carried out in the presence of a base selected from N,N -Diisopropylethylamine.

[0133] As an optional embodiment, in step (3), the molar ratio of compound B to base is 1:(0.5~5), for example, it can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, etc.

[0134] As an optional embodiment, in step (3), the reagent used for the deprotection treatment is trifluoroacetic acid.

[0135] As an optional embodiment, in step (3), the temperature of the deprotection treatment is 30-40°C, for example, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, etc., and the time of the deprotection treatment is 1-3 h, for example, 1 h, 1.2 h, 1.4 h, 1.6 h, 1.8 h, 2 h, 2.2 h, 2.4 h, 2.6 h, 2.8 h, 3 h, etc.

[0136] As an optional embodiment, in step (3), the deprotection treatment comprises: dropping the reaction solution obtained after the condensation reaction in step (3) into a trifluoroacetic acid solution, filtering and drying to obtain a compound represented by formula I.

[0137] As an optional embodiment, in step (4), the radioactive labeling comprises the following steps:

[0138] The sodium acetate solution, the compound solution represented by Formula I and the radioactive nuclide solution are mixed and reacted to obtain the Her2 targeting nuclide probe.

[0139] As an optional embodiment, the volume ratio of the sodium acetate solution to the radionuclide solution is 1:1.

[0140] As an optional embodiment, the concentration of the sodium acetate solution is 1~3 M, for example, it can be 1 M, 1.2 M, 1.5 M, 1.8 M, 2 M, 2.2 M, 2.5 M, 2.8 M, 3 M, etc., preferably 2 M, with a pH of 4.

[0141] As an optional embodiment, the concentration of the compound solution represented by Formula I is 5×10 -6 M.

[0142] As an optional embodiment, the radioactivity of the radionuclide solution is 1 to 10 mCi, for example, it can be 1 mCi, 2 mCi, 3 mCi, 4 mCi, 5 mCi, 6 mCi, 7 mCi, 8 mCi, 9 mCi, 10 mCi, etc., preferably 5 mCi.

[0143] As an optional embodiment, in step (4), the temperature of the radioactive labeling is 85-95°C, for example, it can be 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, etc., and the time of the radioactive labeling is 5-20 min, for example, it can be 5 min, 6 min, 8 min, 10 min, 12 min, 14 min, 15 min, 16 min, 18 min, 20 min, etc.

[0144] As a preferred embodiment, in step (4), the radioactive labeling specifically comprises the following steps:

[0145] A 5 mL EP tube was used as a reaction vessel, and 1 mL 2M pH = 4 sodium acetate solution, 10 μg of the compound solution represented by formula 1, and 1 mL 68 Ga radionuclide solution (5 mCi), the mixed leaves were heated to 90°C, reacted for 10 min, and the Her2-targeted nuclide probe was obtained. 68 Ga-LA-PEG 2n -Y.

[0146] In a third aspect, the present invention provides a use of the Her2 targeting radionuclide probe or its racemate, stereoisomer, or pharmaceutically acceptable salt as described in the first aspect in the preparation of an agent for tumor imaging.

[0147] The present invention relates to a Her2-targeted nuclide probe and its application, and specifically to a compound shown in formula I, or its precursor compound, isotope compound, salt or hydrate, wherein the compound is labeled with a radionuclide to obtain a class of Her2-targeted nuclide probes, which can be used as diagnostic and therapeutic reagents in Her2 protein-highly expressed lesions in humans or animals, in particular as tumor imaging agents and radionuclide therapeutic drugs. In animal experiments, the radioactive complex of the present invention has a high tumor / muscle ratio and has good application prospects.

[0148] As an optional embodiment, the tumor includes any one of a liver cancer tumor, a pancreatic cancer tumor, a colon cancer tumor, a gastric cancer tumor, a breast cancer tumor or a head and neck cancer tumor.

[0149] As an optional embodiment, the present invention provides a liver cancer tumor development model and a method for establishing the same, which specifically includes the following steps: inoculating a Her2 high-expressing cell line human liver cancer into the armpit of a mouse, and injecting the Her2 radionuclide probe of the present invention via tail vein injection.

[0150] It should be noted that after the liver tumor imaging model was established, small animal PET imaging equipment was used to visualize liver tumors using small molecules.

[0151] In a fourth aspect, the present invention provides a use of the Her2-targeted radionuclide probe or its racemate, stereoisomer, or pharmaceutically acceptable salt as described in the first aspect in the preparation of a reagent for identifying Her2-overexpressing tumors.

[0152]

Term Explanation

[0153] As mentioned in the present invention, the term "pharmaceutically acceptable salt" means that the salt is not only physiologically acceptable to the subject, but also refers to a synthetic substance with pharmaceutical use value, such as a salt formed as an intermediate when performing chiral separation. Although the salt of this intermediate cannot be directly administered to the subject, the salt can play a role in obtaining the final product of the present invention.

[0154] As mentioned in the present invention, the pharmaceutically acceptable salt of the compound of formula I is a salt formed with a base or an alkali metal. The acid that forms a pharmaceutically acceptable salt with the compound of formula I includes an inorganic acid and an organic acid. More specifically, the alkali metal that forms a pharmaceutically acceptable salt with the compound of formula I includes but is not limited to lithium, sodium, potassium, magnesium, calcium, aluminum, zinc, etc.; the base that forms a pharmaceutically acceptable salt with the compound of formula I includes but is not limited to choline, diethanolamine, morpholine, etc.

[0155] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.

[0156] Example 1

[0157] This embodiment provides a Her2-targeted nuclide probe, which is a radioactive nuclide 68 Ga-labeled LA-PEG2-NOTA, the structural formula of the LA-PEG2-NOTA is as follows:

[0158]

[0159] The radionuclide 68 Ga-labeled LA-PEG2-NOTA (denoted as 68 The synthetic route of Ga-LA-PEG2-NOTA) is as follows:

[0160]

[0161] (1) Preparation of Compound A1:

[0162] Boc-NH-PEG 2 -COOH (263 mg, 1 mmol) was dissolved in 4 mL of DMF and stirred until completely dissolved. Then, dipyrrolidine ( N -succinimidyloxy)carbonium hexafluorophosphate (483 mg, 1.176 mmol), lapatinib (581 mg, 1 mmol) and DIEA (151 mg, 1.176 mmol) were added and stirred at 37 °C for 24 h. After the reaction, 20 mL of dichloromethane and 20 mL of water were added to the reaction system for extraction. The lower layer of the solution was collected and dried to obtain compound A1.

[0163] (2) Preparation of compound B1:

[0164] 4 mL of trifluoroacetic acid was added to compound A1, and the mixture was stirred at 37°C for 2 h. The solution was spin-dried to obtain compound B1.

[0165] (3) Preparation of the compound LA-PEG2-NOTA represented by formula I:

[0166] NOTA-bis(tBu)ester (415 mg, 1 mmol) was placed in a round-bottom flask and dissolved in 20 mL DMF. N -succinimidyloxy)carbonium hexafluorophosphate (483 mg, 1.176 mmol), DIEA (258 mg, 2 mmol), and compound B1 (726 mg, 1 mmol) were added and stirred at 37°C for 24 h. After the reaction, 20 mL of dichloromethane and 20 mL of water were added to the reaction system for extraction. The lower layer of the solution was collected and dried to obtain compound C1. Compound C1 was added to trifluoroacetic acid solution, stirred at 37°C for 2 h, filtered and dried to obtain compound LA-PEG2-NOTA shown in formula I.

[0167] (4) Radionuclide labeling:

[0168] Use a 5 mL EP tube as a reaction container, add 1 ml of 2M pH = 4 sodium acetate solution, 10 μg of the compound LA-PEG2-NOTA solution of Formula I, 1 mL 68 Ga solution (5 mCi), the mixture was heated to 90 °C and reacted for 10 min to obtain a Her2-targeted nuclide probe 68 Ga-LA-PEG2-NOTA.

[0169] The structure was characterized by high performance liquid chromatography and mass spectrometry, and the results of structure determination are as follows:

[0170] like Figure 1 As shown, 68 The purity of Ga-LA-PEG2-NOTA is: 96.05%.

[0171] like Figure 2 As shown, LCMS (ESI): m / z: Chemical Formula: C 47 H 56 CIF 8 O 12 S, [M+H]found 1010.85, [M+2H]found 506.3.

[0172] Example 2

[0173] This embodiment provides a Her2-targeted nuclide probe, which is a radioactive nuclide 68 Ga-labeled LA-PEG2-DOTA, the structural formula of the LA-PEG2-DOTA is as follows:

[0174]

[0175] The radionuclide 68 Ga-labeled LA-PEG2-DOTA (denoted as 68 The synthetic route of Ga-LA-PEG2-DOTA) is as follows:

[0176]

[0177] (1) Preparation of compound A1: the same as in Example 1.

[0178] (2) Preparation of compound B1: the same as in Example 1.

[0179] (3) Preparation of Compound C2: The difference from Example 1 is that NOTA-bis(tBu)ester is replaced by an equimolar amount of DOTA-bis(tBu)ester to prepare Compound C2.

[0180] (4) Radionuclide labeling: The difference from Example 1 is that the LA-PEG2-NOTA solution of the compound represented by Formula I is replaced by an equal mass of LA-PEG2-DOTA solution to prepare a radionuclide probe targeting Her2. 68 Ga-LA-PEG2-DOTA.

[0181] The structure was characterized by high performance liquid chromatography and mass spectrometry, and the results of structure determination are as follows:

[0182] like Figure 3 As shown, 68 The purity of Ga-LA-PEG2-DOTA is: 93.253%.

[0183] like Figure 4 As shown, LCMS (ESI): m / z: Chemical Formula: C 51 H 63 CIF 9 O 14 S, [M+H]found 1112.55, [M+2H]found 557.25.

[0184] Application Example 1

[0185] This application example provides an application of a Her2-targeted radionuclide probe in the specific identification of liver cancer.

[0186] The Her2 high-expressing cell line HepG2 and the Her2 low-expressing cell line MDA-MB-231 were inoculated in the axilla of Balb / c nude mice, and 1 nmol of the Her2-targeted nuclide probe provided in Example 1 was injected into the tail vein of each mouse. 68 Ga-LA-PEG2-NOTA molecule and small animal PET / CT in vivo imaging system were used to evaluate the effectiveness of diagnosing liver cancer.

[0187] Figure 5 The Her2 targeting nuclide probe provided in Example 1 68 The liver tumor-specific targeting effect of Ga-LA-PEG2-NOTA. Figure 5 As shown, 1 h after injection, HepG2 tumor-bearing mice showed high radioactivity signals in the tumor area, while the surrounding normal tissues 68 Ga-LA-PEG2-NOTA was gradually metabolized and reached the clinical imaging requirement TBR after 1 hour. MDA-MB-231 tumor-bearing mice had no radioactive signals in the tumor area. This shows that 68 Ga-LA-PEG2-NOTA has good specificity in identifying Her2-overexpressing tumors.

[0188] In summary, the present invention aims to provide a near-infrared fluorescent probe and its preparation method and application, which can actively target Her2, can be quickly cleared in normal tissues, and stay in the tumor site for a long time, so as to achieve the effect of in vivo diagnosis. It has a good active targeting effect when identifying liver cancer. This probe retains the water solubility of the dye and the specificity for tumor cells. It has great development potential in the fields of tumor surgery and medical cell labeling.

[0189] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A Her2 targeting radionuclide probe, characterized in that: The Her2 targeting nuclide probe comprises a compound of formula 1 labeled with a radionuclide: Formula 1; The radionuclide is 68 Ga.

2. A method for preparing a Her2 targeting nuclide probe according to claim 1, characterized in that: The preparation method comprises: (1) Lapatinib and compound PG-L-PEG 2n -COOH undergoes condensation reaction to obtain compound A; wherein the reaction formula is as follows: ； Wherein, PG represents a protecting group of an amino group, the L group is selected from NH, and n is 1; (2) Compound A is subjected to deprotection treatment to obtain compound B; wherein the reaction formula is as follows: ； Wherein, PG represents a protecting group of an amino group, the L group is selected from NH, the L' group is selected from -NH2, and n is 1; (3) Compound B and a chelating agent are subjected to a condensation reaction and then to a deprotection treatment to obtain a compound represented by Formula I; wherein the reaction formula is as follows: ； Wherein, the chelating agent is selected from ; L group is selected from NH, L' group is selected from -NH2, n is 1; Y group is ； (4) Mixing the sodium acetate solution, the compound solution represented by Formula I and the radioactive nuclide solution, and reacting them to obtain the Her2-targeted nuclide probe.

3. The method for preparing the Her2 targeting nuclide probe according to claim 2, characterized in that: In step (1), the lapatinib and the compound PG-L-PEG 2n -COOH molar ratio (0.5~2):1; and / or, the PG is a protecting group of an amino group, and the protecting group of the amino group is selected from Boc; And / or, in step (1), the temperature of the condensation reaction is 30-40°C, and the time of the condensation reaction is 12-24 h; And / or, in step (1), the condensation reaction is carried out in a solvent selected from dimethyl sulfoxide and / or N,N - dimethylformamide; And / or, in step (1), the condensation reaction is carried out under a protective gas atmosphere, and the protective gas is selected from nitrogen; And / or, in step (1), the condensation reaction is carried out in the presence of a condensing agent, and the condensing agent is selected from dipyrrolidino ( N -succinimidyloxy)carbonium hexafluorophosphate; And / or, in step (1), the PG-L-PEG 2n The molar ratio of -COOH to the condensing agent is 1:(1.2~2); And / or, in step (1), the condensation reaction is carried out in the presence of a base, and the base is selected from N,N -diisopropylethylamine; And / or, in step (1), the PG-L-PEG 2n The molar ratio of -COOH to base is 1:(0.5~5).

4. The method for preparing the Her2 targeting nuclide probe according to claim 2, characterized in that: In step (2), the reagent used for the deprotection treatment is trifluoroacetic acid; And / or, in step (2), the temperature of the deprotection treatment is 30-40° C., and the time of the deprotection treatment is 1-3 h.

5. The method for preparing the Her2 targeting nuclide probe according to claim 2, characterized in that: In step (3), the molar ratio of compound B to chelating agent is (0.5-2):1; And / or, in step (3), the temperature of the condensation reaction is 30-40°C, and the time of the condensation reaction is 12-24 h; And / or, in step (3), the condensation reaction is carried out in a solvent selected from dimethyl sulfoxide and / or N,N - dimethylformamide; and / or, in step (3), the condensation reaction is carried out under a protective gas atmosphere, wherein the protective gas is selected from nitrogen; And / or, in step (3), the condensation reaction is carried out in the presence of a condensation agent, and the condensation agent is selected from dipyrrolidino ( N -succinimidyloxy)carbonium hexafluorophosphate; And / or, in step (3), the molar ratio of compound B to the condensing agent is 1:(1.2-2); And / or, in step (3), the condensation reaction is carried out in the presence of a base, and the base is selected from N,N -diisopropylethylamine; And / or, in step (3), the molar ratio of compound B to the base is 1: (0.5~5); And / or, in step (3), the reagent used for the deprotection treatment is trifluoroacetic acid; And / or, in step (3), the temperature of the deprotection treatment is 30-40° C., and the time of the deprotection treatment is 1-3 h.

6. The method for preparing the Her2 targeting nuclide probe according to claim 2, characterized in that: In step (4), the volume ratio of the sodium acetate solution to the radionuclide solution is 1:1; And / or, the concentration of the sodium acetate solution is 1-3 M and the pH is 4; And / or, the concentration of the compound solution represented by formula I is 5×10 -6 M; and / or, the radioactivity of the radionuclide solution is 1 to 10 mCi; And / or, in step (4), the reaction temperature is 85-95° C., and the reaction time is 5-20 min.

7. Use of the Her2 targeting nuclide probe or a pharmaceutically acceptable salt thereof according to claim 1 in the preparation of a reagent for tumor imaging; in, The tumor is selected from any one of liver cancer tumors, pancreatic cancer tumors, colon cancer tumors, gastric cancer tumors, breast cancer tumors or head and neck cancer tumors.

8. Use of the Her2-targeted radionuclide probe or a pharmaceutically acceptable salt thereof according to claim 1 in the preparation of a reagent for identifying Her2-overexpressing tumors.

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