Polymer contrast agent

Abstract

The invention provides a polymer contrast agent. The present invention pertains to a copolymer obtained by binding a chelating agent molecule to a copolymer X containing structural units represented by formulae (A), (B), and (C). [In the formula, R1, R2 and R3 may be the same or different and each represents a hydrogen atom or a C1-3 alkyl group; r4 represents a C1-3 alkyl group; r5 represents a hydrogen atom, a C1-18 alkyl group, a 3-to 8-membered cycloalkyl group which may have a substituent, an adamantyl group, a C6-18 aryl group which may have a substituent, or a 5-to 10-membered heteroaryl group which may have a substituent; x1, X2, and X3 may be the same or different and each represents an oxygen atom, a sulfur atom, or N-R7; r6 represents a hydrogen atom, a leaving group or a linking group; r7 represents a hydrogen atom or a C1-3 alkyl group; m represents an integer of 1 to 100; and n represents an integer of 0-3. ] # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a polymer contrast agent that can be used for nuclear magnetic resonance imaging, and more particularly to a polymer contrast agent containing a paramagnetic metal. Background Art

[0002] In recent years, research on drug delivery systems (DDS) has been actively conducted as a technology for effectively and safely delivering drugs to disease sites. Among them, as a technology that utilizes the structural characteristics of disease sites to improve the selectivity of drug aggregation, the demand for DDS using nanoparticles as drug delivery carriers is increasing.

[0003] Despite the innovative progress in treatment and diagnostic technology, cancer still accounts for a large proportion of deaths related to non-infectious diseases. As molecular targeted therapy using antibody drugs becomes more popular, the development of in vitro diagnostic agents for the purpose of examining genes related to malignant tumors is being actively promoted as a diagnostic agent for cancer. However, there are still cancers that are difficult to detect at an early stage, so it is hoped that various diagnostic methods will be used to further improve diagnostic accuracy.

[0004] Various imaging diagnostic techniques are known, but magnetic resonance imaging (MRI) is an excellent tomographic imaging method that is not affected by radiation exposure and has a high spatial resolution. The imaging method using MRI is roughly divided into contrast MRI using a contrast agent and pure MRI without a contrast agent. As a contrast agent in contrast MRI, gadolinium (Gd), which is a paramagnetic body, is mostly used. Since Gd is a metal of a rare earth element, it is highly toxic in the body, so a compound in which Gd is used as a coordination compound using a chelating agent is used.

[0005] In the identification of diseases using contrast-enhanced MRI, the contrast enhancement effect obtained by contrast media and its temporal changes are utilized.

[0006] Existing contrast agents diffuse rapidly throughout the body and are excreted after administration, so the time available for imaging is short, and it is difficult to obtain significant effects in imaging tumors other than the brain. Therefore, they are now used to obtain auxiliary data. In this context, sodium gadoxetate (sold as EOB-Primovist inj. Syringe., manufactured and sold by Bayer Pharmaceuticals) imparts a specific uptake effect on normal liver cells by converting the substituent of the chelating agent into an aromatic ring. Since this effect can prolong the retention time of the contrast agent in normal liver tissue, it can be used to identify liver tumors, but cannot be used to identify tumors of other organs. Due to the above situation, MRI contrast agents that can identify tumors of various organs on a large scale have not yet been put into practical use.

[0007] Under such circumstances, the development of pharmaceuticals using nanotechnology has been actively studied. In solid cancer tissues, since the structure of new blood vessels (tumor blood vessels) is not yet mature compared to normal blood vessels, intercellular spaces of about hundreds of nm are generated in the vascular endothelium, and the permeability of substances is high. It is known that through this structural feature, high molecular weight bodies containing nanoparticles selectively penetrate tumor blood vessels and accumulate in solid cancer tissues. Furthermore, in solid cancer tissues, the lymphatic system involved in the discharge of polymers is dysfunctional, so the infiltrated nanoparticles continue to be retained in the tissue (Enhanced permeability and retention effect, Enhanced permeability and retention effect, EPR effect). General low-molecular drugs leak out of blood vessels due to membrane permeation of vascular cells, so they are non-selectively distributed in tissues and do not accumulate in solid cancer tissues. According to the methodology of the EPR effect, the distribution of drug delivery using nanoparticles in tissues is controlled by the permeability of intercellular spaces of vascular endothelial cells, which will lead to an increase in the tissue selectivity of drug distribution for solid cancer. Therefore, the EPR effect has become a powerful academic basis for the development of nanotechnology-based pharmaceuticals (nanomedicines) targeting solid cancers.

[0008] It is believed that the drug delivery process in the EPR effect is via the blood flow, and the blood vessel leakage process of nanoparticles is passive. Therefore, in order to maximize the aggregation of nanoparticles in solid cancer, it is important to give the constituent components of the nanoparticles as drug delivery carriers a molecular design that can withstand long-term retention in the blood. Therefore, for drug delivery carriers, it is required to have the ability to avoid the following obstacles, that is, non-specific interactions with blood constituents; foreign body recognition of the reticuloendothelial system (RES) in the liver, spleen and lungs; glomerular filtration in the kidneys, etc. In addition, it is known that these obstacles can be overcome by optimizing the particle characteristics such as particle size or surface modification using biocompatible polymers. For example, the particle size of the drug delivery carrier is ideally greater than the threshold of kidney clearance, i.e., about 6nm, and less than 200nm that can be exempted from being recognized by RES.

[0009] In addition, the particle size of known drug delivery carriers also has an impact on the tissue permeability of disease sites. For example, a comparative study has been conducted on the anticancer activity of drug-encapsulated nanoparticles with a particle size of 30nm, 50nm, 70nm and 100nm that show equal retention in the blood, and it is known that the drug-encapsulated nanoparticles with a particle size of 30nm have a high therapeutic effect (non-patent literature 1) due to reaching the deep part of the disease site. Therefore, it is considered that the particle size of the nanoparticles used in drug delivery carriers targeted with solid cancer is preferably small as much as possible within the range of avoiding kidney clearance.

[0010] As nanoparticles for drug delivery carriers, methods using liposomes, emulsifiers or colloidal dispersions of nanoparticles, methods using biological raw materials such as albumin, methods using natural polymers such as natural polysaccharides, or methods using synthetic polymers have been developed. Among them, synthetic polymers can prepare nanoparticles with precisely controlled particle sizes by appropriately selecting monomers as constituent components and synthesis methods, so they can be widely used as constituent components of drug delivery carriers.

[0011] For example, the method of utilizing the amphiphilic block copolymer comprising a hydrophilic segment and a hydrophobic segment as a drug delivery carrier has been disclosed. The block copolymer spontaneously associates in an aqueous medium with intermolecular hydrophobic interactions, etc. as a driving force to form core-shell nanoparticles (polymer micelles). It is known that the inner package or low-molecular drug can be combined in the hydrophobic segment of the polymer micelle, and the obtained inner package drug polymer micelle shows higher stability in blood, and selectively aggregates in solid cancer due to the EPR effect, thus compared with the solution administration of low-molecular drugs, bringing higher anticancer activity (patent document 1). However, polymer micelles are the associations of multiple molecules, so the particle diameter of about 30nm is the lower limit that can be prepared. In addition, in the application of MRI contrast agents, methods have been developed using iron microparticles coated with polysaccharides (Non-patent Document 2), methods of encapsulating paramagnetic metal coordination compounds in liposomes (Patent Document 2), and methods of forming polymer micelles by combining paramagnetic metal coordination compounds with synthetic polymers (block copolymers) (Patent Document 3). However, in any of these methods, the lower limit of the particle size of nanoparticles is about 20 nm, and it is impossible to achieve fine size control of the particle size of about 10 nm to avoid the influence of renal clearance.

[0012] On the other hand, in the nanoparticles formed by the known synthetic polymer, the material (hereinafter referred to as single chain nanoparticle (SCNP)) that forms particles using chemical crosslinking, hydrophobic interaction, ionic bonding, etc. in the single chain as driving force forms small diameter nanoparticles with a particle diameter of less than 20nm (non-patent literature 3). Therefore, although the usefulness of SCNP as a drug delivery carrier is expected, the technology that can accurately control its particle diameter has not yet been found.

[0013] Prior art literature

[0014] Patent Literature

[0015] Patent Document 1: Japanese Patent No. 3270592

[0016] Patent Document 2: Japanese Patent No. 5883797

[0017] Patent Document 3: Japanese Patent No. 4892378

[0018] Non-patent literature

[0019] Non-patent document 1: H. Cabral et al., Nat. Nanotechnol. 6 815-823 (2011)

[0020] Non-patent document 2: Avnesh S. Thakor et al., J Nucl Med. 57, 1833-1837 (2016)

[0021] Non-patent document 3: Jose A. Pomposo, Single-Chain Polymer Nanoparticles: Synthesis, Characterization, Simulations, and Applications (2017) Summary of the invention

[0022] Technical problem to be solved by the invention

[0023] The technical problem to be solved by the present invention is to provide a new polymer contrast agent, and more specifically, to provide a polymer contrast agent for MRI that can identify tumors in various organs over a wide range.

[0024] Technical solutions for solving technical problems

[0025] The inventors of the present invention have conducted in-depth research to solve the above-mentioned technical problems and found that the terpolymer of acrylic acid derivatives forms SCNPs in water. In addition, in addition to being able to precisely control the particle size of SCNPs to a microscale of about 10nm below 20nm, a new polymer for drug delivery carriers with high tumor aggregation has been successfully created. In addition, the terpolymer derivatives in which contrast agent molecules are combined with SCNPs in which contrast agent molecules are carried on the polymer have also been successfully created. In addition, contrast agent molecules combined with SCNPs were applied to subcutaneous transplantation model mice of colorectal cancer, and the results confirmed excellent imaging ability.

[0026] The present invention relates to the following inventions.

[0027] [1] A copolymer in which chelating agent molecules are bonded to a copolymer X comprising structural units represented by the following formulae (A), (B) and (C) (hereinafter sometimes referred to as a chelating agent-bonded copolymer).

[0028]

[0029] [Where R1 , R 2 and R 3 Same or different, indicating hydrogen atoms or C 1-3 Alkyl; R 4 Represents C 1-3 Alkyl; R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; X 1 , X 2 and X 3 The same or different, representing oxygen atoms, sulfur atoms or NR 7 ; R 6 represents a hydrogen atom, a leaving group or a connecting group; R 7 Represents a hydrogen atom or C 1-3 Alkyl; m represents an integer of 1 to 100; n represents an integer of 0 to 3.]

[0030] [2] The copolymer according to [1] above, wherein the polymer X is a copolymer formed by polymerization of three monomers represented by the following general formulas (1) to (3).

[0031]

[0032] [Where R 1 , R 2 and R 3 Same or different, indicating hydrogen atoms or C 1-3 Alkyl; R 4 Represents C 1-3 Alkyl; R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; X 1 , X 2 and X 3 The same or different, representing oxygen atoms, sulfur atoms or NR 7 ; R 6 represents a hydrogen atom, a leaving group or a connecting group; R 7 Represents a hydrogen atom or C 1-3 Alkyl; m represents an integer of 1 to 100; n represents an integer of 0 to 3.]

[0033] [3] The copolymer according to [1] or [2], wherein R 1 A hydrogen atom.

[0034] [4] The copolymer according to any one of [1] to [3] above, wherein R 2 A hydrogen atom.

[0035] [5] The copolymer according to any one of [1] to [4] above, wherein R 3 A hydrogen atom.

[0036] [6] The copolymer according to any one of [1] to [5] above, wherein R 4 It is methyl.

[0037] [7] The copolymer according to any one of [1] to [6] above, wherein R 5 is a C which may have a substituent 6-18 Aryl.

[0038] [8] The copolymer according to any one of [1] to [7] above, wherein R 5 It is phenyl.

[0039] [9] The copolymer according to any one of [1] to [8], wherein R 6 A hydrogen atom.

[0040]

[10] The copolymer according to any one of [1] to [8] above, wherein R 6 The leaving group is a group represented by the following formula (4):

[0041]

[0042]

[11] The copolymer according to any one of [1] to [8] above, wherein R 6 The connecting group is a group selected from the following formulas (5) to (7):

[0043]

[0044]

[12] The copolymer according to any one of [1] to

[11] , wherein X 1 For oxygen atoms.

[0045]

[13] The copolymer according to any one of [1] to

[12] , wherein X 2 For oxygen atoms.

[0046]

[14] The copolymer according to any one of [1] to

[13] above, wherein X 3 For oxygen atoms.

[0047]

[15] The copolymer according to any one of [1] to

[14] above, wherein m is an integer of 4 to 22.

[0048]

[16] The copolymer according to any one of [1] to

[15] above, wherein n is 1.

[0049]

[17] The copolymer described in [1] to

[16] above, wherein the ratio of the structural units (A), (B) and (C) is 0.01 to 100 parts by mass of (B) and 0.1 to 100 parts by mass of (C) per 1 part by mass of (A).

[0050]

[18] The copolymer according to any one of [2] to

[16] above, which is obtained by polymerizing 0.01 to 100 parts by mass of the monomer (2) and 0.1 to 100 parts by mass of the monomer (3) relative to 1 part by mass of the monomer (1).

[0051]

[19] The copolymer according to any one of [1] to

[18] above, wherein the number average molecular weight is 5,000 to 150,000.

[0052]

[20] The copolymer according to any one of [1] to

[19] above, wherein the chelating agent molecule is a molecule having a residue represented by the following formula (a):

[0053]

[0054] [Where R 8 represents a hydrogen atom or a hydroxyalkyl group; R 9 and R 10 represents a hydrogen atom or -[(CH2) o -L-(CH2) p ]-*;X 4 represents oxygen atom, sulfur atom, NR 7 or -CH2-O-; Y and Y' represent a hydrogen atom, a methyl group or a hydroxyl group, or Y and Y' together represent an oxygen atom; L represents an arylene group, a cycloalkylene group, -SS-, -C(O)O-, -OC(=O)-, -C(=O)NH-, -NHC(=O)-, -NHC(=O)O-, -OC(=O)NH-, or a peptide bond containing 1 to 4 amino acid residues, * represents a bond with a copolymer, o and p independently represent integers of 0 to 10, wherein R 9 When it is a hydrogen atom, R 10 For -[(CH2) o -L-(CH2) p ]-*, R 9 For -[(CH2) o -L-(CH2) p ]-*, R 10 is a hydrogen atom.]

[0055]

[21] The copolymer as described in any one of [1] to

[19] above, wherein the chelating agent molecule is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), 1-(2-hydroxypropyl)-1,4,7,10-tetraazacyclododecane-1,2,3-triacetic acid (HP-DO3A), 10-[1,1,1-tris(hydroxymethyl)methyl]-1,4,7-tricarboxymethyl -1,4,7,10-tetraazacyclododecane (DO3A-butrol), 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid-10-(2-thioethyl)acetamide (DO3A-Thiol) or S-2-(4-aminobenzyl)-1,4,7,10-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA-p-NH2-Bn).

[0056]

[22] The copolymer according to any one of [1] to

[21] above, wherein the bonding between the chelating agent molecules and the copolymer X is covalent bonding or non-covalent bonding.

[0057]

[23] A polymer contrast agent comprising the copolymer described in any one of [1] to

[22] above and a paramagnetic metal (hereinafter sometimes referred to as a contrast agent molecule-bound copolymer).

[0058]

[24] The polymer contrast agent according to any one of [1] to

[23] above, wherein the paramagnetic metal is gadolinium or manganese.

[0059]

[25] An image diagnostic agent comprising the copolymer according to any one of [1] to

[22] and a paramagnetic metal.

[0060]

[26] The diagnostic imaging agent according to any one of [1] to

[23] above, wherein the paramagnetic metal is gadolinium or manganese.

[0061]

[27] A single-chain nanoparticle comprising the copolymer according to any one of [1] to

[22] above.

[0062]

[28] A pharmaceutical composition comprising the copolymer according to any one of [1] to

[25] above.

[0063]

[29] A single-chain nanoparticle comprising the polymer contrast agent described in

[23] or

[24] above.

[0064]

[30] A single-chain nanoparticle comprising the image diagnostic agent described in

[25] or

[26] above.

[0065] Effects of the Invention

[0066] As can be seen from the examples described below, the high molecular contrast agent formed by carrying contrast agent molecules on the SCNP obtained by the self-association of the copolymer of the present invention shows a time-dependent change in contrast ability in C26-transplanted cancer-bearing mice, and can therefore be used as an imaging diagnostic agent for malignant tumors. In addition, it has high contrast ability at low dosages, and therefore can provide an imaging diagnostic agent for malignant tumors that can take into account both enhancement of the effect and suppression of side effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 The copolymer obtained in Example 1 is measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0068] Figure 2 This is a diagram showing a chromatogram obtained by gel permeation chromatography (GPC) of the copolymer obtained in Example 1.

[0069] Figure 3 The copolymer obtained in Example 69 is measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0070] Figure 4 This is a diagram showing a chromatogram obtained by gel permeation chromatography (GPC) for the copolymer obtained in Example 69.

[0071] Figure 5 This is a graph showing the UV spectrum of the copolymer obtained in Example 98 measured using UV spectrometry (UV).

[0072] Figure 6 is the chelating agent-bound copolymer obtained in Example 106, measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0073] Figure 7 is the chelating agent-bound copolymer obtained in Example 134, measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0074] Figure 8 is the chelating agent-bound copolymer obtained in Example 142, measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0075] Fig. 9 is the chelate-binding copolymer obtained in Example 150, measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0076] Fig.10 is the chelating agent-bound copolymer obtained in Example 151, measured by nuclear magnetic resonance spectroscopy (NMR). 1 Figure 1 H-NMR spectrum.

[0077] Fig.11 This is a graph showing the particle size measurement results (scattered intensity distribution) of the Gd-DOTA-bound SCNPs obtained in Example 152 by dynamic light scattering (DLS).

[0078] Fig.12 This is a graph showing the time-dependent changes in the imaging ability of the Gd-DOTA-bound SCNP obtained in Example 152 in an imaging test of C26-transplanted cancer-bearing mice. DETAILED DESCRIPTION

[0079] Unless otherwise specified, the terms used in this specification are used with the meanings commonly used in the field. Hereinafter, the present invention will be described in more detail.

[0080] In this specification, the term "nanoparticle" refers to a structure having a particle size of 100 nm or less.

[0081] In this specification, "single-chain nanoparticles (SCNPs)" refer to nanoparticles formed by chemical crosslinking, hydrophobic interaction, ionic bonding, etc. within a single chain as a driving force. 20 nm or less also means a relatively small particle size in most nanoparticles.

[0082] In this specification, the "initiator" means an initiator for thermal radical polymerization such as an azo compound or a peroxide.

[0083] In the present specification, the "chain transfer agent" refers to a compound that causes a chain transfer reaction during radical polymerization, and is preferably a compound having a thiocarbonyl group.

[0084] In this specification, the term “C 1-3 The term "alkyl group" refers to a linear or branched alkyl group having 1 to 3 carbon atoms, and examples thereof include methyl, ethyl, n-propyl, and isopropyl.

[0085] In this specification, the term “C 1-18 The term "alkyl" refers to a linear or branched alkyl group having 1 to 18 carbon atoms, and examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl.

[0086] In the present specification, the term "3- to 8-membered cycloalkyl group which may have a substituent" means a cyclic alkyl group having 3 to 8 carbon atoms, and examples thereof include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. The substituent is not particularly limited, and examples thereof include halogen atoms, alkyl groups having 1 to 6 carbon atoms, alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, hydroxyl groups, alkoxy groups having 1 to 6 carbon atoms, amino groups, alkylamino groups having 1 to 6 carbon atoms, two alkylamino groups having 1 to 6 carbon atoms in which the alkyl groups are the same or different, thiol groups, alkylthio groups having 1 to 6 carbon atoms, carboxyl groups, alkoxycarbonyl groups having 1 to 6 carbon atoms, and carbamoyl groups.

[0087] In this specification, the term "C 6-18 "Aryl" means a monocyclic or condensed polycyclic aromatic hydrocarbon group, examples of which include phenyl, naphthyl, anthracenyl, phenanthrenyl, terphenyl, pyrene, In addition, the term "C optionally substituted" refers to 6-14 The term "aryl" means a monocyclic or condensed polycyclic aromatic hydrocarbon group, and examples thereof include phenyl, naphthyl, anthryl, phenanthryl, and the like. The substituent is not particularly limited, and examples thereof include halogen atoms, alkyl groups having 1 to 6 carbon atoms, alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, hydroxyl groups, alkoxy groups having 1 to 6 carbon atoms, amino groups, alkylamino groups having 1 to 6 carbon atoms, two alkylamino groups having 1 to 6 carbon atoms in which the alkyl groups are the same or different, thiol groups, alkylthio groups having 1 to 6 carbon atoms, carboxyl groups, alkoxycarbonyl groups having 1 to 6 carbon atoms, and carbamoyl groups.

[0088] In the present specification, the term "5- to 10-membered heteroaryl group which may have a substituent" means a 5- to 10-membered monocyclic aromatic heterocyclic group or a condensed aromatic heterocyclic group in which the atoms constituting the ring include, in addition to carbon atoms, 1 to 4 heteroatoms selected from nitrogen atoms, oxygen atoms and sulfur atoms. Examples of the monocyclic aromatic heterocyclic group include furanyl, thienyl, pyrrolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, imidazolyl, pyrazolyl, thiazolyl, oxazolyl, isoxazolyl, 1,3,4-thiadiazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, tetrazolyl and the like. Examples of the fused aromatic heterocyclic group include benzofuranyl, benzothienyl, quinoxalinyl, indolyl, isoindolyl, isobenzofuranyl, chromanyl, benzimidazolyl, benzothiazolyl, benzoxazolyl, quinolyl, isoquinolyl, etc. In addition, the term "6- to 10-membered heteroaryl group which may have a substituent" means a 6- to 10-membered monocyclic aromatic heterocyclic group or a fused aromatic heterocyclic group in which the atoms constituting the ring include, in addition to carbon atoms, 1 to 4 heteroatoms selected from nitrogen atoms, oxygen atoms, and sulfur atoms. Examples of the monocyclic aromatic heterocyclic group include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, etc. Examples of the condensed aromatic heterocyclic group include benzofuranyl, benzothienyl, quinoxalinyl, indolyl, isoindolyl, isobenzofuranyl, chromanyl, benzimidazolyl, benzothiazolyl, benzoxazolyl, quinolyl, isoquinolyl, etc. The substituent is not particularly limited, and examples thereof include halogen atoms, alkyl groups having 1 to 6 carbon atoms, alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, hydroxyl groups, alkoxy groups having 1 to 6 carbon atoms, amino groups, alkylamino groups having 1 to 6 carbon atoms, alkylamino groups having 1 to 6 carbon atoms, two alkylamino groups having 1 to 6 carbon atoms in which the alkyl groups are the same or different, thiol groups, alkylthio groups having 1 to 6 carbon atoms, carboxyl groups, alkoxycarbonyl groups having 1 to 6 carbon atoms, and carbamoyl groups.

[0089] In the present specification, examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0090] In the present specification, the "hydroxyalkyl group" refers to a linear or branched alkyl group having 1 to 3 carbon atoms in which one hydrogen atom is substituted with a hydroxy group, and examples thereof include a hydroxymethyl group, a hydroxyethyl group, and a hydroxypropyl group.

[0091] In the present specification, the "arylene group" refers to a divalent aromatic hydrocarbon ring group having 6 to 10 carbon atoms, and examples thereof include a phenylene group and a naphthylene group.

[0092] In the present specification, the "cycloalkylene group" refers to a divalent cyclic saturated hydrocarbon group having 3 to 7 carbon atoms, and examples thereof include cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, and cycloheptylene.

[0093] In this specification, "contrast agent" refers to a compound administered into a living body for the purpose of improving the accuracy of image diagnosis, and is a drug used for MRI, computed tomography (CT), positron emission tomography (PET), single photon emission computed tomography (SPECT), ultrasonic image diagnosis, etc. These contrast agents are usually compounds (contrast agent molecules) in which various chelating agent molecules are coordinated with paramagnetic metals. The contrast agent molecules are carried on the copolymer by electrostatic interaction, hydrogen bonding, hydrophobic interaction or covalent bonding with the copolymer X of the present invention.

[0094] In the present specification, "chelating agent molecule" refers to a compound that forms a coordination compound by coordination bonding with a metal ion. The metal ion is preferably a paramagnetic metal ion.

[0095] In this specification, "pharmaceutical composition" refers to a composition consisting of a copolymer (hereinafter sometimes referred to as a chelating agent-bound copolymer or a contrast agent molecule-bound copolymer) obtained by binding a chelating agent molecule or a contrast agent molecule (supported by electrostatic interaction, hydrogen bonding, hydrophobic interaction or covalent bonding) to the copolymer X of the present invention and a carrier. As a mode of supporting the contrast agent molecule, when the contrast agent molecule-bound copolymer forms nanoparticles, the contrast agent molecule can be present on the surface of the particle, the contrast agent molecule can be encapsulated in the nanoparticle, or a combination of these modes.

[0096] One embodiment of the present invention is a copolymer in which a chelating agent molecule or a contrast agent molecule is bound to a copolymer X comprising structural units represented by the following formulae (A), (B) and (C) (chelating agent molecule-bound copolymer, contrast agent molecule-bound copolymer).

[0097]

[0098] [Where R 1 , R 2 and R 3 Same or different, indicating hydrogen atoms or C 1-3 Alkyl; R 4 Represents C 1-3 Alkyl; R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; X 1 , X2 and X 3 The same or different, representing oxygen atoms, sulfur atoms or NR 7 ; R 6 represents a hydrogen atom, a leaving group or a connecting group; R 7 Represents a hydrogen atom or C 1-3 Alkyl; m represents an integer of 1 to 100; n represents an integer of 0 to 3.]

[0099] In the copolymer X of the present invention, the structural unit (A) functions as a unit imparting hydrophilicity, and the structural unit (B) functions as a unit imparting hydrophobicity. In addition, the structural unit (C) functions as a scaffold for the effective ingredient (drug, contrast agent molecule) to be bound to the copolymer X, the chelating agent molecule-bound copolymer, or the contrast agent molecule-bound copolymer. The copolymer X, the chelating agent molecule-bound copolymer, or the contrast agent molecule-bound copolymer of the present invention has these three structural units, and thus has the property of forming SCNPs in water, and can precisely control the particle size of the formed SCNPs to a microscale of less than 20 nm, and functions as a drug delivery carrier with high tumor aggregation.

[0100] R in the structural unit (A) 1 Represents a hydrogen atom or C 1-3 The alkyl group is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom, an ethyl group or a propyl group, and is more preferably a hydrogen atom.

[0101] X 1 represents an oxygen atom, a sulfur atom or NR 7 , preferably an oxygen atom, a sulfur atom or NH, more preferably an oxygen atom.

[0102] m represents an integer of 1 to 100, preferably an integer of 3 to 100, and is preferably 3 to 80, more preferably 4 to 60, further preferably 4 to 40, and further preferably 4 to 22 from the viewpoint of imparting good hydrophilicity.

[0103] R 4 Represents C 1-3 More specifically, the alkyl group is a methyl group, an ethyl group, an n-propyl group or an isopropyl group, preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0104] R in the structural unit (B) 2 Represents a hydrogen atom or C 1-3 The alkyl group is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom, an ethyl group or a propyl group, and is more preferably a hydrogen atom.

[0105] X 2 represents an oxygen atom, a sulfur atom or NR 7 , preferably an oxygen atom, a sulfur atom or NH, more preferably an oxygen atom.

[0106] n represents an integer of 0 to 3, preferably an integer of 1 to 3, and more preferably 1.

[0107] R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 An aryl group or a 5- to 10-membered heteroaryl group which may have a substituent, but from the viewpoint of imparting hydrophobicity to the structural unit (B), C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; more preferably C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; more preferably C 1-18 Alkyl, 3-8 membered cycloalkyl, adamantyl or C 6-18 On the other hand, a 3- to 8-membered cycloalkyl group which may have a substituent, an adamantyl group, a C 6-14 Aryl or 6- to 10-membered heteroaryl group which may have a substituent. Here, the substituent is preferably one or more selected from the group consisting of a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, and an alkynyl group having 2 to 6 carbon atoms.

[0108] R in the structural unit (C) 3 Represents a hydrogen atom or C 1-3 An alkyl group is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom, an ethyl group or a propyl group, and is more preferably a hydrogen atom.

[0109] X 3 represents an oxygen atom, a sulfur atom or NR 7 , but is preferably an oxygen atom, a sulfur atom or NH, more preferably an oxygen atom.

[0110] R 6 represents a hydrogen atom, a leaving group or a linking group. The leaving group is a group that can be detached when the structural unit (C) is combined with a drug (contrast agent molecule) or a chelating agent molecule, and the linking group is a group that can be used for crosslinking when the structural unit (C) is combined with a drug (contrast agent molecule) or a chelating agent molecule. As these leaving groups or linking groups, preferably C which may have a substituent 1-18 Alkyl, 3- to 8-membered cycloalkyl which may have a substituent, C 7-19Aralkyl. Here, as a substituent, for example, there can be mentioned a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an amino group, an alkylamino group having 1 to 6 carbon atoms, two alkylamino groups having 1 to 6 carbon atoms in which the alkyl groups are the same or different, a thiol group, an alkylthio group having 1 to 6 carbon atoms, a carboxyl group, an alkoxycarbonyl group having 1 to 6 carbon atoms, a carbamoyl group, etc. As a linking group among these groups, a group having a functional group such as a hydroxyl group, an amino group, a thiol group, a carboxyl group, etc. as a substituent is preferred.

[0111] As R 6 Preferred specific examples of the leaving group include a group represented by the following formula (4).

[0112]

[0113] As R 6 Preferred specific examples of the linking group include groups selected from the following formulae (5) to (7).

[0114]

[0115] The copolymer X of the present invention is a copolymer having structural units shown in formulas (A), (B) and (C). The copolymer X may be a random copolymer or a block copolymer, preferably a random copolymer. The composition ratio of each structural unit in one molecule is preferably a ratio of 0.01 to 100 parts by mass of (B) and 0.1 to 100 parts by mass of (C) when (A) is 1 part by mass; more preferably, a ratio of 0.05 to 18 parts by mass of (B) and 0.1 to 20 parts by mass of (C) when (A) is 1 part by mass; particularly preferably, a ratio of 0.05 to 4 parts by mass of (B) and 0.1 to 16 parts by mass of (C) when (A) is 1 part by mass.

[0116] The degree of polymerization of the copolymer X of the present invention is not particularly limited, but the number average molecular weight is preferably 5,000 to 150,000, more preferably 8,000 to 150,000.

[0117] In the copolymer of the present invention, as described above, the monomer represented by the general formula (1) functions as a unit imparting hydrophilicity, and the monomer represented by the general formula (2) functions as a unit imparting hydrophobicity. In addition, the monomer represented by the general formula (3) functions as a scaffold for combining drugs with the copolymer. The monomer that functions as the hydrophobic unit represented by the general formula (2) can be exemplified by the monomer represented by the following formula.

[0118]

[0119]

[0120] In the general formula (1), R 1 Represents a hydrogen atom or C 1-3 An alkyl group is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom, an ethyl group or a propyl group, and is more preferably a hydrogen atom.

[0121] In the general formula (2), R 2 Represents a hydrogen atom or C 1-3 An alkyl group is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom, an ethyl group or a propyl group, and is more preferably a hydrogen atom.

[0122] In the general formula (3), R 3 Represents a hydrogen atom or C 1-3 An alkyl group is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom, an ethyl group or a propyl group, and is more preferably a hydrogen atom.

[0123] In the general formula (1), R 4 Represents C 1-3 Specifically, the alkyl group is a methyl group, an ethyl group, an n-propyl group or an isopropyl group, preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0124] In the general formula (1), X 1 represents an oxygen atom, a sulfur atom or NR 7 , but is preferably an oxygen atom, a sulfur atom or NH, more preferably an oxygen atom.

[0125] In the general formula (1), m represents an integer of 1 to 100, preferably an integer of 3 to 100, and preferably 3 to 80, more preferably 4 to 60, further preferably 4 to 40, further more preferably 4 to 22 from the viewpoint of imparting good hydrophilicity.

[0126] In the general formula (2), R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 The aryl group or the 5- to 10-membered heteroaryl group which may have a substituent is preferably C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent, more preferably C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 An aryl group or an optionally substituted 5- to 10-membered heteroaryl group, preferably a C 1-18 Alkyl, 3-8 membered cycloalkyl, adamantyl or C 6-18On the other hand, a 3- to 8-membered cycloalkyl group which may have a substituent, an adamantyl group, a C 6-14 Aryl or 6- to 10-membered heteroaryl group which may have a substituent. Here, the substituent is preferably one or more selected from the group consisting of a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, and an alkynyl group having 2 to 6 carbon atoms.

[0127] In the general formula (2), X 2 represents an oxygen atom, a sulfur atom or NR 7 , preferably an oxygen atom, a sulfur atom or NH, more preferably an oxygen atom.

[0128] In the general formula (2), n represents an integer of 0 to 3, preferably an integer of 1 to 3, and more preferably 1.

[0129] In the general formula (3), R 6 represents a hydrogen atom, a leaving group or a linking group. As these leaving groups or linking groups, preferably C 1-18 Alkyl, 3- to 8-membered cycloalkyl which may have a substituent, C 7-19 Aralkyl. Here, as a substituent, for example, there can be mentioned a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an amino group, an alkylamino group having 1 to 6 carbon atoms, two alkylamino groups having 1 to 6 carbon atoms in which the alkyl groups are the same or different, a thiol group, an alkylthio group having 1 to 6 carbon atoms, a carboxyl group, an alkoxycarbonyl group having 1 to 6 carbon atoms, a carbamoyl group, etc. As a linking group among these groups, a group having a functional group such as a hydroxyl group, an amino group, a thiol group, a carboxyl group, etc. as a substituent is preferred.

[0130] As R 6 Preferred specific examples of the leaving group include a group represented by the following formula (4).

[0131]

[0132] As R 6 Preferred specific examples of the linking group include groups selected from the following formulae (5) to (7).

[0133]

[0134] In the general formula (3), X 3 represents an oxygen atom, a sulfur atom or NR 7 , but is preferably an oxygen atom, a sulfur atom or NH, more preferably an oxygen atom.

[0135] The copolymer X of the present invention is formed by copolymerizing three monomers represented by general formulas (1) to (3). The copolymerization may be random copolymerization or block copolymerization, and is preferably formed by random copolymerization. Regarding the mixing ratio of the three monomers, it is preferred that 0.01 to 100 parts by mass of the monomer (2) and 0.1 to 100 parts by mass of the monomer (3) are polymerized when the mass part of the monomer (1) is set to 1, more preferably 0.05 to 18 parts by mass of the monomer (2) and 0.1 to 20 parts by mass of the monomer (3) are polymerized, and it is particularly preferred that 0.05 to 4 parts by mass of the monomer (2) and 0.1 to 16 parts by mass of the monomer (3) are polymerized.

[0136] In addition, "solvates" coordinated with various solvents are also included in the copolymer X of the present invention. In the present specification, examples of "solvates" include hydrates and ethanolates. Any number of solvents may be coordinated with the copolymer X of the present invention.

[0137] The copolymer X of the present invention can be produced by various known methods. The production method is not particularly limited, and for example, it can be produced according to the basic polymer synthesis method described below.

[0138]

[0139] [wherein, R' represents a hydrogen atom or C 1-3 Alkyl, R" represents the above R 4 , R 5 or R 6 The groups shown.]

[0140] This reaction represents a step of making a chain transfer agent (II) and an initiator react with a monomer (I) to produce a polymer (III). This reaction can be carried out without a solvent, or in an alcohol such as methanol, ethanol, 1-propanol, 2-propanol; an ether such as diethyl ether, tetrahydrofuran, 1,4-dioxane; an aromatic hydrocarbon such as benzene, toluene, xylene; a halogenated hydrocarbon such as dichloromethane, chloroform, 1,2-dichloroethane; N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, acetonitrile, ethyl acetate, etc., preferably using an aromatic hydrocarbon such as toluene and xylene as a solvent. The chain transfer agent can use 2-(dodecylthiocarbonylthio)-2-methylpropionic acid (DDMAT), cyanomethyl dodecyl trithiocarbonate (CDTTC), 2-cyano-2-propyl dodecyl trithiocarbonate (CPDTTC), 4-cyano-4-[(dodecylsulfanyl-thiocarbonyl)sulfanyl]pentanoic acid (CDSPA), 2-(dodecylsulfanylthiocarbonylthio)-2-methylpropionic acid 3-azido-1-propanol ester (N3-CTA), etc., preferably DDMAT. When the chain transfer agent is used for polymerization, the copolymer X of the present invention adopts a structure obtained by partially combining a part or all of the structure of the chain transfer agent. When the copolymer X contains the structure of the chain transfer agent, the structure can be removed by an appropriate method. The initiator may be an azo polymerization initiator such as 2,2'-azobisisobutyronitrile (AIBN), 1,1'-azobis(cyclohexanecarbonitrile) (ACHN), 2,2'-azobis-2-methylbutyronitrile (AMBN), 2,2'-azobis-2,4-dimethylvaleronitrile (ADVN), dimethyl-2,2'-azobis(2-methylpropionate) (MAIB), etc., preferably AIBN. The reaction temperature is 0 to 300°C, preferably 0 to 150°C, more preferably 1 to 100°C; the reaction time is 1 minute to 48 hours, preferably 5 minutes to 24 hours. In this reaction, by reacting in the presence of monomers (I) of different structures, a copolymer X by random copolymerization can be produced.

[0141] The chelating agent bonded to the copolymer X is a molecule having a residue represented by the following formula (a).

[0142]

[0143] [Where R 8 represents a hydrogen atom or a hydroxyalkyl group; R 9 and R 10 represents a hydrogen atom or -[(CH2) o -L-(CH2) p ]-*;X 4 represents oxygen atom, sulfur atom, NR 7or -CH2-O-; Y and Y' represent a hydrogen atom, a methyl group or a hydroxyl group, or Y and Y' together represent an oxygen atom; L represents an arylene group, a cycloalkylene group, -SS-, -C(O)O-, -OC(=O)-, -C(=O)NH-, -NHC(=O)-, -NHC(=O)O-, -OC(=O)NH-, or a peptide bond containing 1 to 4 amino acid residues; * represents a bond with a copolymer; o and p independently represent an integer of 0 to 10, wherein R 9 When it is a hydrogen atom, R 10 For -[(CH2) o -L-(CH2) p ]-*, R 9 For -[(CH2) o -L-(CH2) p ]-*, R 10 is a hydrogen atom.]

[0144] Examples of the chelating agent include 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A), 1-(2-hydroxypropyl)-1,4,7,10-tetraazacyclododecane-1,2,3-triacetic acid (HP-DO3A), 10-[1,1,1-tris(hydroxymethyl)methyl]-1,4,7-tricarboxymethyl-1,4,7,10-tetraazacyclododecane (DO3A-butrol), 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A-butrol), and 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A-butrol). Azacyclododecane-N,N',N",N"'-tetraacetic acid mono-(N-hydroxysuccinimide) ester (DOTA-NHS), [(2S,5S,8S,11S)-4,7-bis-carboxymethyl-2,5,8,11-tetramethyl-1,4,7,10-tetraazacyclododec-1-yl]acetic acid (M4DO3A), [(2S,5S,8S,11S)-4,7,10-tris-carboxymethyl-2,5,8,11-tetramethyl-1,4,7,10-tetraazacyclododec-1-yl]acetic acid (M4DOTA), α,α',α ”,α”'-tetramethyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTMA), (R)-2-[(2S,5S,8S,11S)-4,7,10-tris-((R)-1-carboxyethyl)-2,5,8,11-tetramethyl-1,4,7,10-tetraazacyclododecane-1-yl]propanoic acid (M4DOTMA), 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid-10-(2-thioethyl)acetamide (DO3A-Thiol), S-2-(4-aminobenzyl)- 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (p-NH2-Bn-DOTA), 2-methyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (MCTA), diethylenetriaminepentaacetic acid (DTPA), 4-carboxy-5,8,11-tris(carboxymethyl)-1-phenyl-2-oxa-5,8,11-triazatridecane-13-oic acid (BOPTA), ethylenediaminetetraacetic acid (EDTA), 3,6,9,15-tetraazabicyclo[9.3.1] Pentadecane-1(15),11,13-triene-3,6,9-triacetic acid (PCTA12), 1,4,8,11-tetraazacyclotetradecane-N,N',N",N"'-tetraacetic acid (TETA), 1,4,7,10-tetraazacyclotridecane-N,N',N",N"'-tetraacetic acid (TRITA), 1,5,9,13-tetraazacyclohexadecane-N,N',N",N"'-tetraacetic acid (HETA), 10-phosphonomethyl-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (MPDO3A), N,N'-bis(2-hydroxybenzyl)-ethylenediamine-diacetic acid (HBED), N,N'-bis-(2-hydroxyphenylglycine)-ethylenediamine (EHPG), 2-[bis[2-[carboxymethyl-[2 -(2-methoxyethylamino)-2-oxoethyl]amino]ethyl]amino]acetate (DTPA-BMEA), N-[2-[bis(carboxymethyl)amino]-3-(4-ethoxyphenyl)propyl]-N-[2-[bis(carboxymethyl)-amino]ethyl]glycine (EOB-DTPA), N,N-bis[2-[bis(carboxymethyl)amino]-ethyl]-L-glutamic acid (DTPA-Glu), N,N-bis[2-[bis(carboxymethyl)amino]-ethyl]-L-lysine (DTPA-Lys), N,N-bis[2-[carboxymethyl[(methylcarbamoyl)methyl]amino]-ethyl]glycine (DTPA-BMA), or (+ / -)-trans-3,10,13,19-tetraazatricyclo[13.3.1.0. 4,9 ]Nodecan-1(19),15,17-triene-3,10,13-triacetic acid (cyclo-PCTA12), etc.

[0145] Examples of the paramagnetic metal ion include gadolinium ion, manganese ion, iron ion, nickel ion, cobalt ion, dysprosium ion, terbium ion and the like. Among them, gadolinium ion and manganese ion are preferred.

[0146] The contrast agent molecule-binding copolymer of the present invention is composed of a chelating agent-binding copolymer and a paramagnetic metal. As the contrast agent molecule, known MRI contrast agents can be used, preferably paramagnetic metal ions and coordination compound molecules of formula (a), more preferably Gd-DOTA, Gd-HP-DO3A, Gd-DO3A-butrol, Gd-DO3A-Thiol, Gd-DOTA-p-NH2-Bn, and particularly preferably Gd-DOTA.

[0147] The salt of the contrast agent molecule-bound copolymer of the present invention is not particularly limited as long as it is a pharmaceutically acceptable salt. Examples of such salts include alkali metal salts such as sodium salts and potassium salts, salts of calcium salts, magnesium salts and metals of Group IIA elements, organic amine salts such as phenethylamine salts, and ammonium salts.

[0148] When geometrical isomers or optical isomers exist in the contrast agent molecule binding copolymer of the present invention, mixtures or separated products of these isomers are also included in the scope of the present invention. Separation of isomers can be carried out by a common method.

[0149] The contrast agent molecule-bound copolymer of the present invention can be produced by various known methods. The production method is not particularly limited, and for example, it can be produced by the synthesis method described below.

[0150]

[0151] [Wherein, R', R", X 4 , Y, Y' or L represents the same group as above, and P1 or P2 represents a protecting group.]

[0152] This reaction represents a step of producing a chelating agent-bonded copolymer (VI) by reacting a linker (IV) and a chelating agent (V) with a copolymer (III) in a solvent or without a solvent, in the presence of a condensing agent, and in the presence or absence of a reaction accelerator.

[0153] The solvent is not particularly limited, and the reaction can be carried out in, for example, alcohols such as methanol, ethanol, 1-propanol, and 2-propanol, ethers such as diethyl ether, tetrahydrofuran, and 1,4-dioxane, aromatic hydrocarbons such as benzene, toluene, and xylene, halogenated hydrocarbons such as dichloromethane, chloroform, and 1,2-dichloroethane, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, acetonitrile, and ethyl acetate. Preferably, a non-protonic polar solvent such as tetrahydrofuran, dichloromethane, or N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, acetonitrile, and ethyl acetate is used.

[0154] The linking group is not particularly limited as long as it can link the copolymer and the chelating agent, and examples thereof include ethylenediamine, N-Boc-ethylenediamine, 1,3-propylenediamine, N-Boc-1,3-propylenediamine, 1,4-butylenediamine, N-Boc-1,4-butylenediamine, 1,5-pentanediamine, N-Boc-1,5-pentanediamine, 1,6-hexanediamine, N-Boc-1,6-hexanediamine, 1,7-heptanediamine, N-Boc-1,7-heptanediamine, 1,8-octanediamine, N-Boc-1,8-octanediamine, 1,9-nonanediamine, N-Boc-1,9-nonanediamine, 1,10-decanediamine, N-Boc-1,10-decanediamine, 2-aminoethanol, 2-(Boc -amino)-1-ethanol, 3-amino-1-propanol, 3-(Boc-amino)-1-propanol, 4-amino-1-butanol, 4-(Boc-amino)-1-butanol, 5-amino-1-pentanol, 5-(Boc-amino)-1-pentanol, 6-amino-1-hexanol, 6-(Boc-amino)-1-hexanol, 7-(Boc-amino)-1-heptanol, 8-(Boc-amino)-1-octanol, 9-(Boc-amino)-1-nonanol, 10-(Boc-amino)-1-decanol, glycolic acid, tert-butyl glycolate, 3-hydroxypropionic acid, tert-butyl 3-hydroxypropanoate, 4-hydroxybutyric acid, tert-butyl 4-hydroxybutyrate, cystamine, N-Boc-cystamine, 6-maleic acid N-succinimide imide caproic acid, N-succinimide 4-maleimidobutyric acid, N-succinimide 3-maleimidopropionic acid, N-succinimide 3-(2-pyridyldithio)propionic acid, N-succinimide 4-(N-maleimidomethyl)cyclohexanecarboxylic acid, N-succinimide, (S)-2-[(S)-2-amino-3-methylbutanamide]-N-[4-(hydroxymethyl)phenyl]-5-ureidopentanamide, [(S)-1-[[(S)-1-[[4-(hydroxymethyl)phenyl]amino]-1-oxo-5-ureidopentan-2-yl]amino]-3-methyl-1-oxobutan-2-yl]carbamic acid (9H-fluoren-9-yl)methyl ester, [(S)-1-[[(S)- allyl 1-[[4-(hydroxymethyl)phenyl]amino]-1-oxo-5-ureidopentan-2-yl]amino]-3-methyl-1-oxobutan-2-yl]carbamate, 6-(2,5-dioxo-2,5-dihydro-1H-pyrrolyl-1-yl)-N-[(S)-1-[[(S)-1-[[4-(hydroxymethyl)phenyl]amino]-1-oxo-5-ureidopentan-2-yl]amino]-3-methyl-1-oxobutan-2-yl]hexanamide, β-alanine, β-alanine tert-butyl ester, or pharmaceutically acceptable salts thereof, preferably N-Boc-ethylenediamine, 2-(Boc-amino)-1-ethanol, tert-butyl glycolate, and N-Boc-cystamine.

[0155] Furthermore, when the structure of the chelating agent includes a functional group capable of linking to the copolymer X, the copolymer and the chelating agent can be directly linked without the intermediary of a linking group.

[0156] The protecting groups represented by P1 and P2 are not particularly limited and can be selected by referring to, for example, the literature (Protective Groups in Organic Synthesis Fifth Edition, John Wiley & Sons, Inc.).

[0157] Examples of the condensing agent include dicyclohexylcarbodiimide (DCC), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (WSC-HCl), diisopropylcarbodiimide (DIPCDI), (1H-benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), (1H-benzotriazol-1-yloxy)tris(pyrrolidinyl)phosphonium hexafluorophosphate (PyBOP), 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazole (4,5-b) pyridine-3-oxide hexafluorophosphate (HATU), (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinyl carbocation hexafluorophosphate (COMU), chloro-N,N,N',N'-tetramethylformamidine hexafluorophosphate (TCFH), 1-[bis(dimethylamino)methylene]-1H-benzotriazole-3-oxide hexafluorophosphate (HBTU ), 1-[bis(dimethylamino)methylene]-1H-benzotriazole-3-oxide tetrafluoroborate (TBTU), 1-[bis(dimethylamino)methylene]-5-chloro-1H-benzotriazole-3-oxide hexafluorophosphate (HCTU), 1-[bis(dimethylamino)methylene]-5-chloro-1H-benzotriazole-3-oxide tetrafluoroborate (TCTU), or phosphonium salt-type or guanidinium salt-type reagents, among which 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride is preferred. salt (WSC-HCl), (1H-benzotriazol-1-yloxy)tris(pyrrolidinyl)phosphonium hexafluorophosphate (PyBOP), 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo(4,5-b)pyridine-3-oxide hexafluorophosphate (HATU), (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinylcarbocation hexafluorophosphate (COMU), chloro-N,N,N',N'-tetramethylformamidine hexafluorophosphate (TCFH).

[0158] Examples of the reaction accelerator include triethylamine, diisopropylethylamine, pyridine, lutidine, picolin, N,N-dimethylaminopyridine (DMAP), 1-methylimidazole, 2,2,6,6-tetramethylpiperidine (TMP), 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), N-methylmorpholine (NMM), 1,8-diazabicyclo[5.4.0]-7-undecene (DBD), and the like. U), 1-hydroxybenzotriazole (HOBt), 6-chloro-1-hydroxybenzotriazole (6-Cl-HOBt), 3,4-dihydro-3-hydroxy-4-oxo-1,2,3-benzotriazine (HOOBt), 1-hydroxy-7-azabenzotriazole (HOAt), etc. Among these, diisopropylethylamine, N,N-dimethylaminopyridine (DMAP), 1-methylimidazole, 2,2,6,6-tetramethylpiperidine (TMP), 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) are preferred.

[0159] The reaction temperature is 0° C. to 100° C., preferably 1° C. to 80° C., and the reaction time is 5 minutes to 1 week, preferably 2 hours to 3 days. In order to facilitate the reaction, the reaction can be carried out under a nitrogen gas stream or an argon gas stream.

[0160]

[0161] [Wherein, R', R", X 4 , Y, Y' or L represents the same group as above, and M represents a paramagnetic metal ion.]

[0162] This reaction represents a step of reacting a paramagnetic metal ion (M) with a chelating agent-binding polymer (VI) to produce a contrast agent molecule-binding copolymer (VII).

[0163] This reaction can be carried out in water, or in an alcohol such as methanol, ethanol, 1-propanol, 2-propanol, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, acetonitrile, ethyl acetate, etc., preferably in water. As paramagnetic metal ions, there is no particular limitation as long as they have coordination ability for the chelating agent, and Fe(2+), Fe(3+), Cu(2+), Ni(2+), Rh(2+), Co(2+), Cr(3+), Gd(3+), Eu(3+), Dy(3+), Tb(3+), Pm(3+), Nd(3+), Tm(3+), Ce(3+), Y(3+), Ho(3+), Er(3+), La(3+), Yb(3+), Mn(3+), Mn(2+), etc. can be used, and Gd(3+) and Mn(2+) are preferably used. The reaction temperature is 0 to 300°C, preferably 0 to 150°C, more preferably 1 to 100°C, and the reaction time is 1 minute to 48 hours, preferably 5 minutes to 24 hours.

[0164] The produced copolymers of the present invention in which the polymer X and contrast agent molecules are bound can be purified by separation and purification methods of polymers generally known in the field of polymer chemistry. Specifically, for example, the methods include extraction, recrystallization, salting out using ammonium sulfate or sodium sulfate, centrifugal separation, dialysis, ultrafiltration, adsorption chromatography, ion exchange chromatography, hydrophobic chromatography, normal phase chromatography, reverse phase chromatography, gel filtration, gel permeation chromatography, affinity chromatography, electrophoresis, countercurrent distribution, or a combination thereof.

[0165] The copolymer X and the contrast agent molecule-bound copolymer of the present invention can be used as carriers for delivering various drugs (contrast agents). For example, the pharmaceutical composition containing the contrast agent molecule-bound copolymer obtained by supporting (encapsulating) the contrast agent in the copolymer X of the present invention has high tumor aggregating ability as confirmed in the test examples described later, and can be used as a contrast agent and / or diagnostic agent for various cancers such as colorectal cancer, duodenal cancer, gastric cancer, pancreatic cancer, liver cancer, lung cancer, uterine cancer, ovarian cancer, brain tumors, etc.

[0166] When the copolymer of the present invention and the contrast agent molecule-combined copolymer are used as drug delivery carriers, the dosage and frequency of administration can be appropriately selected in consideration of the dosage form, the patient's age, weight, the nature or severity of the symptoms to be treated, etc. The dosage or frequency of administration is not limited. When the polymer containing the drug is intravenously injected by injection, it is preferred to administer 0.12 mg to 12,000,000 mg per adult (60 kg), for example, once, more preferably 1.2 mg to 1,200,000 mg, and particularly preferably 12 to 120,000 mg.

[0167] The pharmaceutical composition of the present invention can be manufactured by mixing the copolymer X of the present invention with a contrast agent molecule. In addition, the copolymer X of the present invention can be manufactured by mixing a chelating agent molecule and then mixing a paramagnetic metal. It is preferred to use the contrast agent molecule of the present invention in conjunction with the copolymer to manufacture single-chain nanoparticles, or to mix the contrast agent molecule after manufacturing the single-chain nanoparticles of the copolymer X of the present invention. The single-chain nanoparticles can be manufactured by a known method.

[0168] In the pharmaceutical composition of the present invention, the contrast agent molecules may be supported on the copolymer X or the contrast agent molecule-bound copolymer by electrostatic interaction, hydrogen bonding, hydrophobic interaction, or covalent bonding.

[0169] The administration route of the pharmaceutical composition of the present invention is preferably the most effective way for treatment, and can be administered in the form of oral administration preparations, injections, or non-oral administration preparations such as transdermal administration preparations, for example, preferably intra-arterial injection, intravenous injection, subcutaneous injection, intramuscular injection, intraperitoneal injection and other non-oral administration, more preferably intra-arterial injection and intravenous injection. The number of administrations should not be limited, for example, it can be listed as: an average of 1 to several administrations per week.

[0170] Various preparations suitable for the route of administration can be prepared by appropriately selecting pharmaceutical additives such as excipients, extenders, binders, wetting agents, disintegrants, lubricants, surfactants, dispersants, buffers, preservatives, solubilizers, antiseptics, flavoring agents, analgesics, stabilizers, isotonic agents, etc., which are commonly used in pharmaceutical preparations, and by conventional methods.

[0171] The preparation additives that can be included in the above-mentioned various preparations are not particularly limited as long as they are additives allowed in medicine. As the example of this preparation additive, it is possible to enumerate: purified water, water for injection, distilled water for injection, organic solvents allowed in medicine, collagen, polyvinyl alcohol, polyvinyl pyrrolidone, carboxyvinyl polymer, sodium alginate, water-soluble dextran, sodium carboxymethyl starch, pectin, xanthan gum, gum arabic, casein, gelatin, agar, glycerol, propylene glycol, polyethylene glycol, vaseline, paraffin, stearyl alcohol, stearic acid, human serum albumin, mannitol, sorbitol, lactose, etc. The additive used can be appropriately selected according to various preparations, and can be used alone or in combination.

[0172] In addition, the injection can also be prepared into a non-aqueous diluent (for example, polyethylene glycol, vegetable oils such as olive oil, alcohols such as ethanol, etc.), a suspending agent or an emulsion. The injection can be sterilized by filtering and sterilizing with a filter, or by using a bactericide. In addition, the injection can be manufactured into a form modulated when used. That is, a sterile solid composition can be prepared by freeze drying, etc., and dissolved in water for injection, distilled water for injection, or other solvents before use.

[0173] [Example]

[0174] The present invention will be described in more detail below using examples. These examples are provided for illustrative purposes and are not intended to limit the embodiments of the present invention.

[0175] [Example 1] Preparation of Poly[(Benzyl acrylate)-co-(Poly(ethylene glycol) methyl ether acrylate)-co-(1-ethoxyethyl acrylate)]

[0176] (1) Synthesis of 1-ethoxyethyl acrylate (EEA)

[0177] Under an argon atmosphere, weigh ethyl vinyl ether (28.725 mL), add phosphoric acid (50 mg) while cooling in an ice bath. Then, add acrylic acid (17.15 mL) and stir at room temperature for 48 hours. Add hydrotalcite (3 g) and stir for another 2 hours to terminate the reaction. After filtering with diatomaceous earth, remove the unreacted ethyl vinyl ether by evaporation. Add phenothiazine as a polymerization inhibitor in a manner to reach 500 ppm, and perform vacuum distillation with calcium hydroxide to purify (distillation temperature is 28-32°C). The obtained 1-ethoxyethyl acrylate is divided into a glass vial and stored at -30°C.

[0178] 13 C NMR (400MHz, CDCl3), δ, ppm: 15.29(-OCH2CH3), 21.16(-COOCH(CH3)), 64.98(-OCH2-), 96.73(-COOCH(CH3)), 128.84(CH2CH-), 131.43(CH2CH-), 166.00(-COO).

[0179] (2) Synthesis of poly[(benzyl acrylate)-co-(poly(ethylene glycol) methyl ether acrylate)-co-(1-ethoxyethyl acrylate)]

[0180] 100 mg of 2-(dodecylthiothiocarbonylthio)-2-methylpropionic acid (DDMAT) was weighed and dissolved in 17.3 mL of toluene to prepare a DDMAT / toluene stock solution (DDMAT concentration was 5.78 mg / mL). Similarly, 22 mg of 2,2'-azobis(2-methylpropionitrile) (AIBN) was weighed and dissolved in 17.3 mL of toluene to prepare an AIBN / toluene stock solution (AIBN concentration was 1.27 mg / mL). In addition, 1.296 g of poly(ethylene glycol) methyl ether acrylate (mPEGA, the average value (n) of the number of repeats of ethylene glycol was 9), 0.394 g of benzyl acrylate (BnA), 0.039 g of 1-ethoxyethyl acrylate, 1.73 mL of the DDMAT / toluene stock solution, and 1.73 mL of the AIBN / toluene stock solution were added, and polymerization was carried out in an oil bath at 70°C. After 90 minutes, the polymerization was terminated, and the copolymer was recovered by reprecipitation or methanol dialysis of the reaction solution. The obtained copolymer was basically a viscous body, so regarding the reprecipitation method, the reaction solution was added dropwise to a centrifuge tube added with a poor solvent (hexane / ethyl acetate = 7 / 3 [v / v]), and recovered by centrifugation (2,000×g, 5 min). The above operation was repeated 3 times, and finally vacuum dried to obtain 1.223 g of poly[(benzyl acrylate)-co-(poly(ethylene glycol) methyl ether acrylate)-co-(1-ethoxyethyl acrylate)].

[0181] The obtained copolymer was measured by NMR. 1 H-NMR spectroscopy analysis of the polymerization degree and number average molecular weight (M n,NMR ), the results show that the degree of polymerization of mPEGA (n = 9) is 102, the degree of polymerization of BnA is 94, the degree of polymerization of EEA is 9, and the degree of polymerization of M n,NMR The molecular weight dispersion (M w / M n ), the result is 1.53.

[0182]

[0183] [Measurement equipment and conditions, etc.]

[0184] (1) 1 H-NMR measurement

[0185] Device: JNM-ECX400 (400MHz) / JEOL

[0186] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0187] Sample concentration: 20mg / mL

[0188] Measurement temperature: 25℃

[0189] Total times: 256 times

[0190] result: Figure 1

[0191] (2) GPC measurement

[0192] Equipment: HPLC-Prominence system / Shimadzu Corporation

[0193] Detector: RID-10A refractive index detector / Shimadzu Corporation

[0194] Column: TSKgelα-2500 column / Tosoh

[0195] (column size is 7.8 mm × 00 mm, particle size is 7 μm, and exclusion limit molecular weight is 5 × 10 3 )

[0196] TSKgelα-4000 column / Tosoh

[0197] (column size: 7.8 mm × 300 mm, particle size: 10 μm, exclusion limit molecular weight: 4 × 10 5 )

[0198] TSKgel Guard Column / Tosoh

[0199] Mobile phase: N,N-dimethylformamide (DMF) containing 10 mmol / L lithium bromide

[0200] Temperature: 40℃

[0201] Flow rate: 0.5mL / min

[0202] Sample concentration: 6mg / mL

[0203] Standard material: Poly(methyl methacrylate) Standard ReadyCal Kit, M p 800-2,200,000Da / SIGMA

[0204] result: Figure 2

[0205] [Table 1]

[0206]

[0207] [Examples 2 to 68]

[0208] The same method as in Example 1 was used by appropriately changing the types of monomers (mPEGA, BnA, EEA), feed amounts, reaction temperatures, and polymerization times, thereby producing polymers having different composition ratios or average molecular weights as shown in the following table.

[0209] [Table 2]

[0210]

[0211]

[0212] [Table 3]

[0213]

[0214]

[0215] [Example 69]

[0216] Preparation of poly[(benzyl acrylate)-co-(poly(ethylene glycol) methyl ether acrylate)-co-(acrylic acid)]

[0217] 110 mg of 2-(dodecylthiothiocarbonylthio)-2-methylpropanoic acid (DDMAT) was weighed and dissolved in 19.0 mL of toluene to prepare a DDMAT / toluene stock solution (DDMAT concentration was 5.78 mg / mL). Similarly, 25 mg of 2,2'-azobis(2-methylpropionitrile) (AIBN) was weighed and dissolved in 19.7 mL of toluene to prepare an AIBN / toluene stock solution (AIBN concentration was 1.27 mg / mL). In addition, 12.96 g of poly(ethylene glycol) methyl ether acrylate (mPEGA, the average value (n) of the number of repeats of ethylene glycol was 9), 3.50 g of benzyl acrylate (BnA), 0.78 g of 1-ethoxyethyl acrylate, 17.3 mL of the DDMAT / toluene stock solution, and 17.3 mL of the AIBN / toluene stock solution were added, and polymerization was carried out in an oil bath at 70°C. After 90 minutes, the polymerization was terminated, and the copolymer was recovered by reprecipitation or methanol dialysis of the reaction solution. The obtained copolymer was basically a viscous body, so regarding the reprecipitation method, the reaction solution was added dropwise to a centrifuge tube to which a poor solvent (hexane / ethyl acetate = 7 / 3 [v / v]) was added, and recovered by centrifugation (2,000×g, 5 min). The above operation was repeated 3 times, and finally vacuum dried. The obtained polymer was treated with 0.5N HCl at room temperature to eliminate the ethoxyethyl group, and 12.41g of poly[(benzyl acrylate)-co-(poly(ethylene glycol) methyl ether acrylate)-co-(acrylic acid)] was obtained.

[0218] The obtained copolymer was measured by NMR. 1 H-NMR spectroscopy analysis of the polymerization degree and number average molecular weight (M n,NMR ), the results show that the polymerization degree of mPEGA (n = 9) is 88, the polymerization degree of BnA is 75, the polymerization degree of EEA is 17, and the polymerization degree of M n,NMR The molecular weight dispersion (M w / M n ), the result is 1.51.

[0219]

[0220] [Measurement equipment and conditions, etc.]

[0221] (1) 1 H-NMR measurement

[0222] Device: JNM-ECX400 (400MHz) / JEOL

[0223] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0224] Sample concentration: 20mg / mL

[0225] Measurement temperature: 25℃

[0226] Total times: 256 times

[0227] result: Figure 3

[0228] (2) GPC measurement

[0229] Equipment: HPLC-Prominence system / Shimadzu Corporation

[0230] Detector: RID-10A refractive index detector / Shimadzu Corporation

[0231] Column: TSKgelα-2500 column / Tosoh

[0232] (column size: 7.8 mm × 300 mm, particle size: 7 μm, exclusion limit molecular weight: 5 × 10 3 )

[0233] TSKgelα-4000 column / Tosoh

[0234] (column size: 7.8 mm × 300 mm, particle size: 10 μm, exclusion limit molecular weight: 4 × 10 5 )

[0235] TSKgel Guard Column / Tosoh

[0236] Mobile phase: N,N-dimethylformamide (DMF) containing 10 mmol / L lithium bromide

[0237] Temperature: 40℃

[0238] Flow rate: 0.5mL / min

[0239] Sample concentration: 6mg / mL

[0240] Standard material: Poly(methyl methacrylate) Standard ReadyCal Kit, M p 800-2,200,000Da / SIGMA

[0241] result: Figure 4

[0242] [Table 4]

[0243]

[0244] [Examples 70 to 97]

[0245] The feed amounts of monomers (mPEGA, BnA, EEA) used in Example 69 and the polymerization time were appropriately changed, and the same method as in Example 69 was used to produce polymers having different composition ratios and average molecular weights as shown in the following table.

[0246] [Table 5]

[0247]

[0248] [Table 6]

[0249]

[0250] [Example 98]

[0251] Transformation of terminal structure of terpolymer

[0252] Weigh 7.00 g of the copolymer obtained in Example 69 and dissolve it in 70 mL of toluene. Add 11 mg of AIBN4 and 100 mg of lauroyl peroxide to the solution and stir overnight in a hot water bath at 80°C. After terminating the reaction by cooling in an ice bath, recover the copolymer by reprecipitation or methanol dialysis of the reaction solution. The obtained copolymer is basically a viscous body, so regarding the reprecipitation method, the reaction solution is added dropwise to a centrifuge tube to which a poor solvent (hexane / ethyl acetate = 7 / 3 [v / v]) is added, and recovered by centrifugation (2,000×g, 5 min). The above operation is repeated 3 times and finally vacuum dried to obtain 6.25 g of a terpolymer with a changed terminal structure.

[0253] The residual rate of the terminal structure of the obtained copolymer was evaluated based on the absorbance of the peak (wavelength: 309 nm) derived from the trithiocarbonate group in the UV spectrum measured using an ultraviolet-visible spectrophotometer and found to be 0.0%.

[0254]

[0255] [Measurement equipment and conditions, etc.]

[0256] (1) UV spectroscopy

[0257] Device: Hitachi Spectrophotometer U-9300 / Hitachi

[0258] Solvent: purified water

[0259] Sample concentration: 4 mg / mL

[0260] Measurement wavelength: 250~500nm

[0261] result: Figure 5

[0262] [Table 7]

[0263] Example Copolymers used Azo compounds used in the reaction The residual rate of terminal structure (%) 98 Embodiment 69 AIBN 0.0

[0264] [Examples 99 to 105]

[0265] The copolymers obtained in Examples 70 to 97 were synthesized in the same manner as in Example 98 by appropriately changing the type and feed amount of the azo compound, thereby synthesizing copolymers having different terminal structures as shown in the following table.

[0266] [Table 8]

[0267] Example Copolymers used Azo compounds used in the reaction The residual rate of terminal structure (%) 99 Embodiment 70 AIBN 0.0 100 Embodiment 74 AIBN 0.0 101 Embodiment 82 AIBN 0.0 102 Embodiment 92 AIBN 3.6 103 Embodiment 93 AIBN 0.0 104 Embodiment 82 MAIB 0.0 105 Embodiment 93 MAIB 0.0

[0268] [Example 106]

[0269] Synthesis of Chelating Agent-Bound Copolymers (Disulfide Bonds)

[0270] 650 mg of the copolymer obtained in Example 98 was weighed and dissolved in 13 mL of DMF, and 166 mg of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinyl carbonium cation hexafluorophosphate (COMU) and 66 μL of 2,2,6,6-tetramethylpiperidine (TMP) were added, and the mixture was stirred at room temperature for 3 hours. Then, 280 mg of Boc-cystamine hydrochloride was added, and the mixture was stirred at 30°C for 3 days. After the reaction solution was dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent was removed by reduced pressure distillation and vacuum drying, and the copolymer was recovered. The obtained copolymer was dissolved in 10 mL of a mixed solution of dichloromethane (DCM) and trifluoroacetic acid (TFA) [DCM / TFA=5 / 3 (v / v)], and stirred overnight at room temperature to perform deprotection. The reaction solution was purified by dialysis (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), and the solvent was removed by reduced pressure distillation and vacuum drying to recover the copolymer. 534 mg of the obtained copolymer was dissolved in 21 mL of DMF, 387 mg of DOTA-tri(tert-butyl ester), 289 mg of COMU and 114 μL of TMP were added, and stirred at 30°C for 3 days. The reaction solution was purified by dialysis (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), and the solvent was removed by reduced pressure distillation and vacuum drying to recover the copolymer. The obtained copolymer was dissolved in 32 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], and stirred at room temperature overnight to deprotect the carboxyl group, and then the solvent was removed by reduced pressure distillation and vacuum drying to obtain 557 mg of a chelating agent-bound copolymer (disulfide linking group).

[0271]

[0272] For the chelating agent-bound copolymer (disulfide linker) before deprotection of the carboxyl group, the 1 The number of chelating agents introduced per one molecule of the copolymer was analyzed by H-NMR spectroscopy and found to be 11 mol / mol.

[0273] [Measurement equipment and conditions, etc.]

[0274] (1) 1 H-NMR measurement

[0275] Device: JNM-ECX400 (400MHz) / JEOL

[0276] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0277] Sample concentration: 20mg / mL

[0278] Measurement temperature: 25℃

[0279] Total times: 256 times

[0280] result: Figure 6

[0281] [Table 9]

[0282]

[0283] [Examples 107 to 133]

[0284] For the copolymers obtained in Examples 69 to 105, the feed amounts of the linking group and the chelating agent were appropriately changed, and copolymers having different numbers of chelating agents introduced per copolymer molecule as shown in the table below were synthesized by the same method as in Example 106.

[0285] [Table 10]

[0286]

[0287] [Example 134]

[0288] Synthesis of Chelating Agent-Bound Copolymers (Amide Bond 1)

[0289] Weigh 400 mg of the copolymer obtained in Example 69, dissolve it in 16 mL of DMF, add 153 mg of COMU and 61 μL of TMP, and stir at room temperature for 3 hours. Then, add 58 mg of N-(tert-butoxycarbonyl)-1,2-ethylenediamine, and stir at 30°C for 3 days. After the reaction solution is dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent is removed by reduced pressure distillation and vacuum drying, and the copolymer is recovered. The obtained copolymer is dissolved in 16 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], and stirred at room temperature overnight to perform deprotection. After the reaction solution is dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent is removed by reduced pressure distillation and vacuum drying, and the copolymer is recovered. The copolymer obtained was dissolved in 28 mL of DMF, 96 mg of DOTA-tri(tert-butyl ester), 89 mg of COMU and 70 μL of TMP were added, and the mixture was stirred at 30°C for 3 days. The reaction solution was purified by dialysis (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), and the solvent was removed by reduced pressure distillation and vacuum drying to recover the copolymer. The copolymer obtained was dissolved in 16 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], and stirred at room temperature overnight to deprotect the carboxyl group, and the solvent was removed by reduced pressure distillation and vacuum drying to obtain 242 mg of a chelating agent-bound copolymer (amide bond 1).

[0290]

[0291] For the chelating agent-bound copolymer (amide bond 1) before deprotection of the carboxyl group, the 1 The number of chelating agents introduced per one molecule of the copolymer was analyzed by H-NMR spectroscopy and found to be 11 mol / mol.

[0292] [Measurement equipment and conditions, etc.]

[0293] (1) 1 H-NMR measurement

[0294] Device: JNM-ECX400 (400MHz) / JEOL

[0295] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0296] Sample concentration: 20mg / mL

[0297] Measurement temperature: 25℃

[0298] Total times: 256 times

[0299] result: Figure 7

[0300] [Table 11]

[0301]

[0302] [Examples 135 to 141]

[0303] For the copolymers obtained in Examples 71 to 78, the feed amounts of the linking group and the chelating agent were appropriately changed, and copolymers having different numbers of chelating agents introduced per copolymer molecule as shown in the table below were synthesized by using the same method as in Example 134.

[0304] [Table 12]

[0305]

[0306] [Example 142]

[0307] Synthesis of Chelating Agent-Bound Copolymers (Amide Bond 2)

[0308] Weigh 300 mg of the copolymer obtained in Example 98, dissolve in 15 mL of DMF, add 65 mg of COMU and 26 μL of TMP, and stir at room temperature for 3 hours. Then, add 114 mg of p-NH2-Bn-DOTA-tetra-tert-butyl ester, and stir at 30°C for 3 days. After the reaction solution is dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent is removed by reduced pressure distillation and vacuum drying to recover the copolymer. The obtained copolymer is dissolved in 32 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], stirred at room temperature overnight, and the carboxyl group is deprotected, and then the solvent is removed by reduced pressure distillation and vacuum drying to obtain 281 mg of a chelating agent-bound copolymer (amide bond 2).

[0309]

[0310] For the chelating agent-bound copolymer (amide bond 2) before deprotection of the carboxyl group, the 1 The number of chelating agents introduced per one molecule of the copolymer was analyzed by H-NMR spectroscopy and found to be 7 mol / mol.

[0311] [Measurement equipment and conditions, etc.]

[0312] (1) 1 H-NMR measurement

[0313] Device: JNM-ECX400 (400MHz) / JEOL

[0314] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0315] Sample concentration: 20mg / mL

[0316] Measurement temperature: 25℃

[0317] Total times: 256 times

[0318] result: Figure 8

[0319] [Table 13]

[0320]

[0321] [Examples 143 to 149]

[0322] For the copolymers obtained in Examples 69 to 97, the feed amounts of the linking group and the chelating agent were appropriately changed, and copolymers having different numbers of chelating agents introduced per copolymer molecule as shown in the table below were synthesized by the same method as in Example 142.

[0323] [Table 14]

[0324]

[0325] [Example 150]

[0326] Synthesis of Chelating Agent-Bound Copolymers (Ester Bond 1)

[0327] 400 mg of the copolymer obtained in Example 98 was weighed and dissolved in 7 mL of dichloromethane. 69 mg of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (WSC-HCl) and 44 mg of 4-(dimethylamino)pyridine (DMAP) were added, and the mixture was stirred at room temperature for 3 hours. Then, 183 μL of 2-(tert-butoxycarbonylamino)-1-ethanol was added, and the mixture was stirred at 30° C. for 3 days. After the reaction solution was dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent was removed by reduced pressure distillation and vacuum drying, and the copolymer was recovered. The obtained copolymer was dissolved in 16 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], and stirred at room temperature overnight to perform deprotection. The reaction solution was purified by dialysis (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), and the solvent was removed by reduced pressure distillation and vacuum drying to recover the copolymer. 350 mg of the obtained copolymer was dissolved in 7 mL of DMF, 118 mg of DOTA-tri(tert-butyl ester), 88 mg of COMU and 35 μL of TMP were added, and stirred at 30°C for 3 days. The reaction solution was purified by dialysis (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), and the solvent was removed by reduced pressure distillation and vacuum drying to recover the copolymer. The obtained copolymer was dissolved in 16 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], stirred at room temperature overnight, and the carboxyl group was deprotected, and the solvent was removed by reduced pressure distillation and vacuum drying to obtain 238 mg of a chelating agent-bound copolymer (ester bond 1).

[0328]

[0329] For the chelating agent-bound copolymer (ester bond 1) before deprotection of the carboxyl group, the 1 The amount of the chelating agent introduced per one molecule of the copolymer was analyzed by H-NMR spectroscopy and found to be 12 mol / mol.

[0330] [Measurement equipment and conditions, etc.]

[0331] (1) 1 H-NMR measurement

[0332] Device: JNM-ECX400 (400MHz) / JEOL

[0333] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0334] Sample concentration: 20mg / mL

[0335] Measurement temperature: 25℃

[0336] Total times: 256 times

[0337] result: Fig. 9

[0338] [Table 15]

[0339]

[0340] [Example 151]

[0341] Synthesis of Chelating Agent-Bound Copolymers (Ester Bond 2)

[0342] Weigh 400 mg of the copolymer obtained in Example 100, dissolve it in 7 mL of dichloromethane, add 69 mg of WSC-HCl and 44 mg of DMAP, and stir at room temperature for 3 hours. Then, add 111 μL of tert-butyl glycolate and stir at 30°C for 3 days. After the reaction solution is dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent is removed by reduced pressure distillation and vacuum drying, and the copolymer is recovered. The obtained copolymer is dissolved in 16 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)] and stirred at room temperature overnight to deprotect the carboxyl group. After the reaction solution is dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), the solvent is removed by reduced pressure distillation and vacuum drying, and the copolymer is recovered. The copolymer obtained was dissolved in 7 mL of DMF, and 174 mg of p-NH2-Bn-DOTA-tetra-tert-butyl ester, 88 mg of COMU and 35 μL of TMP were added, and stirred at 30°C for 3 days. The reaction solution was dialyzed and purified (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff: 3.5 kDa, external solution: methanol), and the solvent was removed by reduced pressure distillation and vacuum drying to recover the copolymer. The copolymer obtained was dissolved in 16 mL of a mixed solution of DCM and TFA [DCM / TFA=5 / 3 (v / v)], and stirred at room temperature overnight to deprotect the carboxyl group, and then the solvent was removed by reduced pressure distillation and vacuum drying to obtain 54 mg of a chelating agent-bound copolymer (ester bond 2).

[0343]

[0344] The chelate-bound copolymer (ester bond 2) before deprotection of the carboxyl group was measured by NMR. 1The number of chelating agents introduced per one molecule of the copolymer was analyzed by H-NMR spectroscopy and found to be 13 mol / mol.

[0345] [Measurement equipment and conditions, etc.]

[0346] (1) 1 H-NMR measurement

[0347] Device: JNM-ECX400 (400MHz) / JEOL

[0348] Solvent: Dimethyl sulfoxide-d6 containing 0.03% tetramethylsilane / Kanto Chemical

[0349] Sample concentration: 20mg / mL

[0350] Measurement temperature: 25℃

[0351] Total times: 256 times

[0352] result: Fig.10

[0353] [Table 16]

[0354]

[0355] [Example 152]

[0356] Preparation of Gd-DOTA-conjugated SCNPs

[0357] 500 mg of the chelating agent-bound copolymer obtained in Example 106 was dissolved in 50 mL of purified water and bubbled with argon for 20 minutes. After adding 313 mg of gadolinium chloride hexahydrate, the pH of the solution was adjusted to 6.5 using a 1N sodium hydroxide aqueous solution. The solution was stirred at 60°C for 3 hours to perform a coordination formation reaction between Gd and DOTA. Afterwards, dialysis purification was performed using purified water as an external liquid (dialysis membrane: Spectra / Por regenerated cellulose membrane 6, molecular weight cutoff value: 3.5 kDa, external liquid: purified water) to crudely purify free Gd. 8.5 mL of 10-fold concentration Dulbecco's phosphate buffer (D-PBS(-)) was added and stirred for 30 minutes to precipitate free Gd as phosphate. After filtering the solution with a filter (pore size 0.2 μm), it was dialyzed again with purified water to remove the salts contained in the buffer. The inner liquid of the obtained dialysis membrane was freeze-dried to obtain 356 mg of Gd-DOTA-bound SCNPs.

[0358] The number of Gd bound per molecule of the Gd-DOTA-bound SCNP copolymer obtained after purification was measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES), and the result was 9.4 mol / mol. In addition, the Z-average particle size and polydispersity index of the Gd-DOTA-bound SCNP dispersed in PBS were measured by dynamic light scattering (DLS), and the result was 9.3 nm (polydispersity index 0.15).

[0359] [Measurement equipment and conditions, etc.]

[0360] (1) ICP-AES measurement

[0361] Device: Sequential high-frequency plasma luminescence device ICPE-9000 / Shimadzu Corporation

[0362] Pre-treatment device: Microwave sample pre-treatment device ETHOS EASY / Milestone General

[0363] Measurement wavelength: 342nm

[0364] Standard solution: Gadolinium standard solution (Gd1000) for ICP analysis / Fujifilm Wako Pure Chemical Industries, Ltd.

[0365] Internal standard substance: Yttrium standard solution (Y1000) for ICP analysis / Fujifilm Wako Pure Chemical Industries, Ltd.

[0366] Sample concentration: 10 mg / mL (polymer conversion)

[0367] (2) DLS assay

[0368] Device: Zetasizer NanoZS / Malvern Instruments Ltd.

[0369] Measurement temperature: 25℃

[0370] Sample concentration: 10mg / mL

[0371] result: Fig.11

[0372] [Table 17]

[0373]

[0374] [Examples 153 to 198]

[0375] For the chelating agent-bound copolymers obtained in Examples 107 to 151, the type and feed amount of the paramagnetic metal were appropriately changed, and by using the same method as Example 152, contrast agent molecule-bound SCNPs having different paramagnetic metal binding numbers per copolymer molecule as shown in the table below were synthesized.

[0376] [Table 18]

[0377]

[0378]

[0379] [Comparative Example 1]

[0380] Preparation of Gadoterate Diglucamide (Magnescope) Solution

[0381] To 4.6 mL of PBS was added 0.4 mL of 10 mL of gadoterate dimeglumine 38% intravenous injection solution (Guerbet Japan Co., Ltd.) to prepare a PBS solution with a Gd content of 0.5 mol / L.

[0382] [Test Example 1] Relaxation Energy Measurement

[0383] The Gd-DOTA-bound SCNP obtained in Example 152 was prepared at Gd ion concentrations of 1, 0.5, 0.25, 0.125, 0.0625, and 0.03125 mmol / L in PBS, and the longitudinal relaxation time (T1 time) and transverse relaxation time (T2 time) were measured. Based on the obtained T1 time and T2 time, the longitudinal relaxation energy (r1) and transverse relaxation energy (r2) were calculated by equations 1 and 2, respectively, and the results were 13.1 and 15.9.

[0384] The T1 time and T2 time of the gadoterate dimeglumine solution (Comparative Example 1) were measured by the same procedure as above. Based on the obtained T1 time and T2 time, r1 was 4.1 and r2 was 4.9.

[0385] [Measurement equipment and conditions, etc.]

[0386] [Measurement device]

[0387] Permanent magnet type 1 Tesla magnetic resonance imaging (MRI) device (1.0 Tesla, ICON, Bruker Bisospin, Ettlingen, Germany)

[0388] [condition]

[0389] Longitudinal relaxation energy measurement (r1):

[0390] Inversion recovery spin echo

[0391] (RARE sequence, TR / TE=20000 / 17msec, RARE factor=4, inversion time=45, 100, 200, 400, 800, 1600, 3200, 6400, 8000, 10000, 120000msec, FOV=3.84×3.84cm, matrix size=64×64, number of slices=1, slice thickness=3mm, NEX=1, scan time=5min 20sec per scan)

[0392] [condition]

[0393] Transverse relaxation energy measurement (r2)

[0394] Multi-echo spin echo

[0395] (Reference measurement: MSME sequence, TR=15000msec, TE=40, 80, 120, 160, 200…3072msec or 10240msec (256step), FOV=3.84×3.84cm, matrix size=64×64, number of slices=1, slice thickness=3mm, NEX=1, scan time=16min 00sec)

[0396] Formula 1 Definition of relaxation energy r1

[0397] 1 / T1=1 / T1 0 +r1×[Gd]

[0398] [where T1 represents the longitudinal relaxation time in water in the presence of contrast agent (s), T1 0 represents the longitudinal relaxation time in water (in the absence of contrast agent) (s), r1 represents the longitudinal relaxation energy (mS -1 s -1 ), and [Gd] represents the concentration of Gd ions contained in the contrast agent (mmol / L)]

[0399] Formula 2 Definition of relaxation energy r2

[0400] 1 / T2=1 / T2 0 +r2×[Gd]

[0401] [where T2 represents the longitudinal relaxation time in water in the presence of contrast agent (s), T2 0 represents the longitudinal relaxation time in water (in the absence of contrast agent) (s), and r2 represents the transverse relaxation energy (mS -1 s -1 ), and [Gd] represents the concentration of Gd ions contained in the contrast agent (mmol / L)]

[0402] [Test Example 2] Angiography Test

[0403] Mouse colon cancer cell line C26 was subcutaneously transplanted into female nude mice (BALB / c-nu / nu, 4 weeks old; Japan SLC (Strain)), and the resulting cancer-bearing model was used for imaging experiments.

[0404] Mouse colorectal cancer cell line C26 subcultured in a CO2 incubator was suspended in liquid culture medium (Double's modified Eagle's medium-high glucose, Sigma-Aldrich) at a cell number of 1×10 6 The nude mice were injected subcutaneously with 50 μL of the drug. After the nude mice were fed for about 10 days, the average tumor volume grew to about 200 mm 3 The Gd-DOTA obtained in Example 152 was combined with SCNP for caudal vein administration, and angiography was performed immediately after administration, 1 hour later, 2 hours later, and 24 hours later. For comparison, a gadoterate dimeglumine solution (Comparative Example 1) was used and administered in the same manner. The dosage of each drug was calculated as 0.4 mmol / kg in terms of Gd.

[0405] The temporal changes in imaging ability are shown in Fig.12 . In the case of Gd-DOTA combined with SCNP, the contrast enhancement effect was confirmed just after administration, reaching a peak 2 hours after administration and lasting until 24 hours later. On the other hand, in the case of gadoteric acid meglumine solution (Comparative Example 1), the contrast enhancement effect was confirmed just after administration, but it weakened to the same level as before administration 1 hour after administration. In addition, the contrast enhancement effect of the gadoteric acid meglumine solution just after administration is weaker than the contrast enhancement effect of Gd-DOTA combined with SCNP 2 hours after administration. The above results show that Gd-DOTA combined with SCNP and gadoteric acid meglumine solution have a better contrast effect.

[0406] [Measurement equipment and conditions, etc.]

[0407] [Measurement device]

[0408] Permanent magnet type 1 Tesla magnetic resonance imaging (MRI) device (1.0 Tesla, ICON, Bruker Bisospin, Ettlingen, Germany)

[0409] [condition]

[0410] T1-weighted images:

[0411] Spin echo method (MSME sequence, TR / TE=400 / 10 msec, FOV=3.84×3.84 cm, matrix size=256×256, number of slices=1, slice thickness=3 mm, NEX=10, scan time=17 min 4 sec).

Claims

1. A copolymer obtained by bonding a chelating agent molecule to a copolymer X comprising structural units represented by the following formulae (A), (B) and (C), wherein: In the formula, R 1 , R 2 and R 3 Same or different, indicating hydrogen atoms or C 1-3 Alkyl; R 4 Represents C 1-3 Alkyl; R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; X 1 , X 2 and X 3 The same or different, representing oxygen atoms, sulfur atoms or NR 7 ; R 6 represents a hydrogen atom, a leaving group or a connecting group; R 7 Represents a hydrogen atom or C 1-3 An alkyl group; m represents an integer of 1 to 100; and n represents an integer of 0 to 3.

2. The copolymer according to claim 1, characterized in that: The polymer X is a copolymer formed by polymerization of three monomers represented by the following general formulas (1) to (3), In the formula, R 1 , R 2 and R 3 Same or different, indicating hydrogen atoms or C 1-3 Alkyl; R 4 Represents C 1-3 Alkyl; R 5 represents hydrogen atom, C 1-18 alkyl, 3- to 8-membered cycloalkyl which may have a substituent, adamantyl, C 6-18 Aryl or 5- to 10-membered heteroaryl which may have a substituent; X 1 , X 2 and X 3 The same or different, representing oxygen atoms, sulfur atoms or NR 7 ; R 6 represents a hydrogen atom, a leaving group or a connecting group; R 7 Represents a hydrogen atom or C 1-3 An alkyl group; m represents an integer of 1 to 100; and n represents an integer of 0 to 3.

3. The copolymer according to claim 1 or 2, characterized in that: R 1 A hydrogen atom.

4. The copolymer according to claim 1 or 2, characterized in that: R 2 A hydrogen atom.

5. The copolymer according to claim 1 or 2, characterized in that: R 3 A hydrogen atom.

6. The copolymer according to claim 1 or 2, characterized in that: R 4 It is methyl.

7. The copolymer according to claim 1 or 2, characterized in that: R 5 is a C which may have a substituent 6-18 Aryl.

8. The copolymer according to claim 1 or 2, characterized in that: R 5 It is phenyl.

9. The copolymer according to claim 1 or 2, characterized in that: R 6 A hydrogen atom.

10. The copolymer according to claim 1 or 2, characterized in that: R 6 The leaving group is a group represented by the following formula (4):

11. The copolymer according to claim 1 or 2, characterized in that: R 6 The connecting group is a group selected from the following formulas (5) to (7):

12. The copolymer according to claim 1 or 2, characterized in that: X 1 For oxygen atoms.

13. The copolymer according to claim 1 or 2, characterized in that: X 2 For oxygen atoms.

14. The copolymer according to claim 1 or 2, characterized in that: X 3 For oxygen atoms.

15. The copolymer according to claim 1 or 2, characterized in that: m is an integer from 4 to 22.

16. The copolymer according to claim 1 or 2, characterized in that: n is 1.

17. The copolymer according to claim 1, characterized in that: The ratio of the structural units (A), (B), and (C) is 0.01 to 100 parts by mass of (B) and 0.1 to 100 parts by mass of (C) per 1 part by mass of (A).

18. The copolymer according to claim 2, characterized in that: The monomer (2) is prepared by polymerizing 0.01 to 100 parts by mass of the monomer (2) and 0.1 to 100 parts by mass of the monomer (3) with respect to 1 part by mass of the monomer (1).

19. The copolymer according to claim 1 or 2, characterized in that: The number average molecular weight is 5000 to 150000.

20. The copolymer according to claim 1 or 2, characterized in that: The chelating agent molecule is a molecule having a residue represented by the following formula (a): In the formula, R 8 represents a hydrogen atom or a hydroxyalkyl group; R 9 and R 10 represents a hydrogen atom or -[(CH2) o -L-(CH2) p ]-*;X 4 represents oxygen atom, sulfur atom, NR 7 or -CH2-O-; Y and Y' represent a hydrogen atom, a methyl group or a hydroxyl group, or Y and Y' together represent an oxygen atom; L represents an arylene group, a cycloalkylene group, -SS-, -C(O)O-, -OC(=O)-, -C(=O)NH-, -NHC(=O)-, -NHC(=O)O-, -OC(=O)NH-, or a peptide bond containing 1 to 4 amino acid residues; * represents a bond with a copolymer; o and p independently represent an integer of 0 to 10, wherein R 9 When it is a hydrogen atom, R 10 For -[(CH2) o -L-(CH2) p ]-*, R 9 For -[(CH2) o -L-(CH2) p ]-*, R 10 A hydrogen atom.

21. The copolymer according to claim 1 or 2, characterized in that: The chelating agent molecule is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), 1-(2-hydroxypropyl)-1,4,7,10-tetraazacyclododecane-1,2,3-triacetic acid (HP-DO3A), 10-[1,1,1-tris(hydroxymethyl)methyl]-1,4,7-tricarboxymethyl-1,4,7,10-tetraazacyclododecane (DO3A-butrol), 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid-10-(2-thioethyl)acetamide (DO3A-Thiol) or S-2-(4-aminobenzyl)-1,4,7,10-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA-p-NH2-Bn).

22. The copolymer according to claim 1 or 2, characterized in that: The binding of the chelating agent molecules to the copolymer X is covalent binding or non-covalent binding.

23. A polymer contrast agent, characterized in that: The invention comprises the copolymer according to claim 1 or 2 and a paramagnetic metal.

24. The polymer contrast agent according to claim 23, characterized in that: The paramagnetic metal is gadolinium or manganese.

25. An image diagnostic agent, characterized in that: The invention comprises the copolymer according to claim 1 or 2 and a paramagnetic metal.

26. The image diagnostic agent according to claim 25, wherein: The paramagnetic metal is gadolinium or manganese.

27. A single-chain nanoparticle, characterized in that: The copolymer comprising claim 1 or 2.

28. A pharmaceutical composition, characterized in that: The copolymer comprising claim 1 or 2.

29. A single-chain nanoparticle, characterized in that: The copolymer comprising claim 1 or 2.

30. A single-chain nanoparticle, characterized in that: Comprising the polymer contrast agent according to claim 23.

31. A single-chain nanoparticle, characterized in that: A diagnostic imaging agent comprising the agent according to claim 25.

Images