Photooxygenation catalyst compound and medicine containing the same

Abstract

[Problem] The present invention addresses the problem of developing a catalyst compound which has blood-brain barrier penetration properties and enables the oxygenation of amyloids in a body upon being irradiated with light from the outside of the body and providing a prophylactic and therapeutic agent for amyloid-related diseases using the catalyst compound. [Solution] It is found that a compound having such a framework that an azobenzene-like structure and boron together form a complex is useful as a novel biocatalyst which can selectively oxygenate an amyloid and can prevent the aggregation of the amyloid upon being irradiated with light while significantly reducing the molecular weight of the amyloid. It is also found that the compound can exhibit an oxygenation activity upon the irradiation with light having a longer wavelength which has high tissue penetration properties and has excellent blood-brain barrier penetration properties.

Description

[Technical field]

[0001] The present invention relates to a medicine for preventing or treating various diseases involving pathogenic amyloids. [Background technology]

[0002] In general, proteins fold to form specific native structures and perform vital functions, but on the other hand, they can misfold and aggregate (amyloidize) into fibrils rich in β-sheet structures. The aggregates (oligomers, protofibrils, and fibrils) produced during this amyloidization process are known to cause various functional disorders (such diseases are collectively called "amyloid diseases"), and more than 35 types of proteins have been identified as causative agents of amyloid diseases. Examples of such amyloids include tau protein, α-synuclein in Parkinson's disease, amylin in diabetes, transthyretin in systemic amyloidosis, and huntingtin in Huntington's disease.

[0003] On the other hand, Alzheimer's disease is a progressive neurodegenerative disease that causes brain atrophy and cognitive decline, and the number of patients is increasing year by year. Alzheimer's disease is also a type of amyloid disease, and its onset is thought to be related to neurotoxicity caused by aggregates formed by amyloid beta (Aβ), and so far, treatments targeting Aβ have been actively researched. Known therapeutic drugs and treatments targeting Aβ include inhibitors of the enzyme that produces Aβ from precursor proteins, Aβ decomposition enzyme promoters, immunotherapy, and Aβ aggregation inhibitors. However, these conventional treatments have problems such as side effects and low pharmacological effects, and have not yet been put to practical use. For this reason, the development of new methods that lead to safe and effective treatment of Alzheimer's disease is desired.

[0004] In response to this, the present inventors have been developing compounds that can reduce the aggregation and toxicity of Aβ through a photooxygenation reaction that adds oxygen atoms to Aβ (Non-Patent Documents 1 to 3, etc.). However, these compounds have a large molecular weight and therefore have low blood-brain barrier permeability, and therefore require the administration of the compounds into the brain by invasive procedures such as surgery, which poses practical problems. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Taniguchi, A. et al., Nat. Chem. 2016, 8, 974-982 [Non-Patent Document 2] Ni, J. et al., M. Chem 2018, 4, 807-820 [Non-Patent Document 3] Suzuki, T. et al., Chem. Commun. 2019, 55, 6165 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the problems of the conventional techniques, an objective of the present invention is to develop a catalytic compound that has blood-brain barrier permeability and enables oxygenation of amyloids in the body by external light irradiation, and to provide a drug for preventing and treating amyloid-related diseases using the same. [Means for solving the problem]

[0007] The present inventors conducted extensive research to solve the above problems and found that a compound having a skeleton in which an azobenzene-like structure and boron are complexed is useful as a novel in vivo catalyst that selectively oxygenates amyloids by irradiation with light and inhibits aggregation while significantly reducing the molecular weight. The inventors also found that the compound exhibits oxygenation activity by irradiation with long-wavelength light that has high tissue permeability, and has excellent permeability through the blood-brain barrier. These findings led to the completion of the present invention. Note that the term "oxygenation" is used herein to refer broadly to the reaction of oxidation, particularly the reaction of binding oxygen atoms.

[0008] That is, in one aspect, the present invention provides <1> A compound represented by the following formula (Ia) or (Ib) or a salt thereof: [ka] (In the formula, X and Y each independently represent an aromatic ring which may be the same or different; R 1 is a substituent selected from the group consisting of an optionally substituted amino group, an alkyl group, an alkoxy group, a sulfo group, a phosphate group, and a heteroaryl group having a hydrophilic substituent, and may be present at any position on X or Y; R 2 is a halogen atom, a selenium atom, or a haloalkyl group having 1 to 3 carbon atoms, and may be present at any position on Y or X; and R 3 is a halogen atom or a haloalkyl group having 1 to 3 carbon atoms; <2> The above, wherein X and Y are benzene rings or naphthalene rings. <1> or a salt thereof; <3> The above-mentioned compound represented by the following formula (IIa) or (IIb): <1> or a salt thereof, [ka] (In the formula, R 1 , R 2 , and R 3 is defined as in claim 1). <4> R 2 is a bromine atom, an iodine atom, or a selenium atom. <1> ~ <3> or a salt thereof; <5> R 3 is a fluorine atom or a fluoroalkyl group having 1 to 3 carbon atoms. <1> ~ <4> 10. The compound or salt thereof according to claim 9, <6> R 1 is represented by the following formula (a), <1> ~ <5> or a salt thereof according to any one of the following: [ka] (wherein the dashed line indicates a connection to X or Y; R 4 is a hydrogen atom, an alkyl group which may have a substituent, or an aromatic ring; R 5 each independently may be the same or different and is a hydrogen atom, an alkyl group which may have a substituent, or an aromatic ring; and n is an integer of 0 to 5; <7> A compound or a salt thereof selected from the group consisting of: [ka] (In the formula, Me represents a methyl group.) This provides:

[0009] In another aspect, the present invention also relates to medicaments and methods of treatment comprising the above compounds, more particularly <8> the above <1> ~ <7> A catalyst for oxygenating pathogenic amyloid, comprising the compound or a salt thereof according to any one of the above items (1) to (4). <9> the above <1> ~ <7> An agent for inhibiting pathogenic amyloid aggregation, comprising the compound according to any one of the above or a salt thereof; <10> the above <1> ~ <7> a pharmaceutical composition comprising the compound or salt thereof according to any one of the above and a pharma- ceutical acceptable carrier; <11> The above-mentioned drug is a preventive or therapeutic drug for a disease associated with pathogenic amyloid. <10> 4. A pharmaceutical composition according to claim 3 ; <12> The disease associated with pathogenic amyloid is Alzheimer's disease. <11> 4. A pharmaceutical composition according to claim 3 ; <13> The present invention relates to a method for producing a preventive or therapeutic agent for a disease involving pathogenic amyloid. <1> ~ <7> Use of a compound or a salt thereof according to any one of the above items (1) to (4). <14> the above <1> ~ <7> A method for preventing or treating a disease associated with pathogenic amyloid, comprising administering an effective amount of the compound or a salt thereof according to any one of the above items (1) to the patient; <15> the above <1> ~ <7> The method includes administering the compound or salt thereof according to any one of the above to a patient, and then irradiating the affected area of ​​the patient with light from outside the body. <14> and <16> The disease associated with pathogenic amyloid is Alzheimer's disease. <14> or <15> The method according to This provides: Effect of the Invention

[0010] According to the present invention, it is possible to provide a novel photooxygenation catalyst compound that has high catalytic activity for oxygenating pathogenic amyloid such as Aβ peptide by irradiation with long-wavelength light having high tissue permeability, and has excellent permeability through the blood-brain barrier. This makes it possible to suppress or reduce the aggregation and toxicity of pathogenic amyloid in the living body (in the brain, etc.) by a non-invasive method of administering the compound intravenously or the like and then irradiating the compound with light from outside the body. Therefore, the present invention makes it possible to prevent and treat diseases involving pathogenic amyloid by a minimally invasive method that has not been available in the past. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 shows MALDI-TOF MS spectra in the photooxygenation reaction of Aβ by the compound of the present invention. [Diagram 2] FIG. 2 is a graph showing the amount of oxygenated Aβ produced in the photooxygenation reaction of Aβ by the compound of the present invention. [Diagram 3] FIG. 3 is a graph showing peptide selectivity in photooxygenation reactions by the compounds of the present invention. [Figure 4]FIG. 4 is a graph showing a comparison of the amounts of oxygenated Aβ produced in Compound 2 and Comparative Example 1 in an Aβ oxygenation reaction. [Diagram 5] FIG. 5 shows (A) the change in the fluorescence spectrum of compound 2 in the presence and absence of aggregated Aβ; (B) the most stable structures of compound 2 in the ground and excited states optimized using density functional theory. [Figure 6] FIG. 6 shows the oxygenation sites in the photooxygenation reaction of Aβ by the compounds of the present invention. [Figure 7] FIG. 7 is a graph showing the inhibition of aggregation in the photooxygenation reaction of Aβ by the compounds of the present invention. [Figure 8] FIG. 8 shows the blood-brain barrier (BBB) ​​permeability of the compounds of the present invention and comparative examples (compounds 3 and 4). [Figure 9] FIG. 9 shows the results of photooxygenation of Aβ by the compound of the present invention in Alzheimer's disease model mice. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of the present invention will be described. The scope of the present invention is not limited to these descriptions, and other than the following examples, the present invention can be appropriately modified and implemented without departing from the spirit of the present invention.

[0013] 1.Definition In this specification, the term "halogen atom" means a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0014] In the present specification, the term "alkyl or alkyl group" may be any of linear, branched, and cyclic aliphatic hydrocarbon groups, or a combination thereof. The number of carbon atoms in the alkyl group is not particularly limited, but may be, for example, an alkyl group having 1 to 20 carbon atoms (C 1~20 ), 1 to 15 carbon atoms (C 1~15 ), 1 to 10 carbon atoms (C 1~10 In the present specification, the alkyl group may have one or more optional substituents. For example, C 1~8Alkyl includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neo-pentyl, n-hexyl, isohexyl, n-heptyl, n-octyl, etc. The substituent may include, but is not limited to, an alkoxy group, a halogen atom (which may be a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an amino group, a mono- or di-substituted amino group, a substituted silyl group, or an acyl. When an alkyl group has two or more substituents, they may be the same or different. The same applies to the alkyl portion of other substituents (e.g., an alkoxy group, an arylalkyl group, etc.) that contain an alkyl portion.

[0015] In the present specification, the term "alkoxy group" refers to a structure in which the alkyl group is bonded to an oxygen atom, and examples thereof include saturated alkoxy groups that are linear, branched, cyclic, or a combination thereof. Suitable examples include methoxy, ethoxy, n-propoxy, isopropoxy, cyclopropoxy, n-butoxy, isobutoxy, s-butoxy, t-butoxy, cyclobutoxy, cyclopropylmethoxy, n-pentyloxy, cyclopentyloxy, cyclopropylethyloxy, cyclobutylmethyloxy, n-hexyloxy, cyclohexyloxy, cyclopropylpropyloxy, cyclobutylethyloxy, and cyclopentylmethyloxy.

[0016] As used herein, the term "aromatic ring" refers to a monocyclic or condensed polycyclic conjugated unsaturated hydrocarbon ring structure, which may contain one or more heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.) as ring-constituting atoms.

[0017] In the present specification, the term "aryl or aryl group" may be either a monocyclic or condensed polycyclic aromatic hydrocarbon group, or may be an aromatic heterocycle containing one or more heteroatoms (e.g., oxygen, nitrogen, or sulfur atoms) as ring constituent atoms. In this case, it is called a "heteroaryl group" or a "heteroaromatic group". In either case of a monocyclic or condensed ring, the aryl may be bonded at any possible position. Non-limiting examples of monocyclic aryl include a phenyl group (Phe), a thienyl group (2- or 3-thienyl group), a pyridyl group, a furyl group, a thiazolyl group, an oxazolyl group, a pyrazolyl group, a 2-pyrazinyl group, a pyrimidinyl group, a pyrrolyl group, an imidazolyl group, a pyridazinyl group, a 3-isothiazolyl group, a 3-isoxazolyl group, a 1,2,4-oxadiazol-5-yl group, or a 1,2,4-oxadiazol-3-yl group. Non-limiting examples of fused polycyclic aryls include 1-naphthyl, 2-naphthyl, 1-indenyl, 2-indenyl, 2,3-dihydroinden-1-yl, 2,3-dihydroinden-2-yl, 2-anthryl, indazolyl, quinolyl, isoquinolyl, 1,2-dihydroisoquinolyl, 1,2,3,4-tetrahydroisoquinolyl, indolyl, isoindolyl, phthalazinyl, quinoxalinyl, benzofuranyl, 2,3-dihydrobenzofuran- Examples of the aryl group include 1-yl group, 2,3-dihydrobenzofuran-2-yl group, naphthyridinyl, dihydronaphthyridinyl, tetrahydronaphthyridinyl, imidazopyridinyl, pteridinyl, purinyl, quinolizinyl, indolizinyl, tetrahydroquinolizinyl, and tetrahydroindolizinyl, 2,3-dihydrobenzothiophen-1-yl group, 2,3-dihydrobenzothiophen-2-yl group, benzothiazolyl group, benzimidazolyl group, fluorenyl group, and thioxanthenyl group. In the present specification, the aryl group may have one or more optional substituents on the ring. Examples of the substituents include, but are not limited to, an alkoxy group, a halogen atom, an amino group, a mono- or di-substituted amino group, a substituted silyl group, or an acyl. When the aryl group has two or more substituents, they may be the same or different.The same applies to the aryl moiety of other substituents containing an aryl moiety (eg, an aryloxy group, an arylalkyl group, etc.). Examples include, but are not limited to, when the aryl group has two or more substituents, they may be the same or different.

[0018] In the present specification, "alkylamino" and "arylamino" refer to an amino group in which the hydrogen atom of the -NH2 group is substituted with one or two of the above alkyl or aryl groups. Examples include methylamino, dimethylamino, ethylamino, diethylamino, ethylmethylamino, benzylamino, etc.

[0019] In the present specification, when a functional group is defined as "optionally substituted", the type of the substituent, the substitution position, and the number of the substituent are not particularly limited, and when it has two or more substituents, they may be the same or different. Examples of the substituent include, but are not limited to, an alkyl group, an alkoxy group, a hydroxyl group, a carboxyl group, a halogen atom, a sulfo group, an amino group, an alkoxycarbonyl group, and an oxo group. These substituents may further have a substituent. Examples of such a substituent include, but are not limited to, a halogenated alkyl group.

[0020] 2. Compounds of the Invention The compound of the present invention has a skeleton in which an azobenzene-like structure and boron are complexed, and is represented by the following formula (Ia) or (Ib). [ka]

[0021] The difference between formula (Ia) and (Ib) is that in formula (Ia), R 1 is connected to X, and R 2 is linked to Y, whereas in formula (Ib) R 2 is connected to X, and R 1 is connected to Y.

[0022] In the formula, X and Y are each independently an aromatic ring which may be the same or different, and are preferably a benzene ring or a naphthalene ring, and more preferably a benzene ring.

[0023] When both X and Y are benzene rings, the compound of the present invention has a structure in which an azobenzene is complexed with boron, and in a preferred embodiment, has a structure represented by the following formula (IIa) or (IIb). [ka]

[0024] In any of formulas (Ia), (Ib), (IIa) and (IIb), R 1 is a substituent selected from the group consisting of an optionally substituted amino group, an alkyl group, an alkoxy group, a sulfo group, a phosphate group, and a heteroaryl group having a hydrophilic substituent. 1 is preferably electron donating and hydrophilic to enhance the solubility of the compound of the present invention. The alkyl group and alkoxy group are preferably linear or branched C1-C 10 More preferably, it is a straight or branched C1 to C5 heteroaryl group. The heteroaryl group in the "heteroaryl group having a hydrophilic substituent" can be, for example, a thiophene or a selenophene; the hydrophilic substituent can be, for example, an amino group or a carboxyl group.

[0025] In the case of formula (Ia), R 1 may be present at any position on X, and in the case of formula (Ib), R 1 may be present at any position on Y. Preferably, R 1 can be linked to X or Y at the meta position relative to the N atom of the azo group, as shown in formulas (IIa) and (IIb).

[0026] In a more preferred embodiment, R 1can be an amino group represented by the following formula (a): [ka]

[0027] In formula (a), the dashed line indicates a connection to X or Y; 4 is a hydrogen atom, an alkyl group which may have a substituent, or an aromatic ring; R 5 are each independently the same or different and each independently represent a hydrogen atom, an alkyl group which may have a substituent, or an aromatic ring; and n is an integer of 0 to 5. 4 and R 5 are each independently the same or different and are a linear or branched C1 to C5 alkyl group, more preferably a methyl group. Also, n is preferably an integer of 1 to 3.

[0028] R 3 is a group capable of producing a heavy atom effect, and in any of formulas (Ia), (Ib), (IIa) and (IIb), is a halogen atom, a selenium atom or a haloalkyl group having 1 to 3 carbon atoms. 3 is preferably a bromine atom, an iodine atom, or a selenium atom; or a C1 to C3 alkyl bromide or alkyl iodide.

[0029] In the case of formula (Ia), R 2 may be present at any position on Y, and in the case of formula (Ib), R 2 may be present at any position on X. Preferably, R 2 can be linked to X or Y at the meta position relative to the N atom of the azo group, as shown in formulas (IIa) and (IIb).

[0030] R 3 In any of formulas (Ia), (Ib), (IIa) and (IIb), R is a halogen atom or a haloalkyl group having 1 to 3 carbon atoms. 3 is preferably a group exhibiting strong electron-withdrawing properties. Typically, R 3is preferably a fluorine atom or a fluoroalkyl group having 1 to 3 carbon atoms. The haloalkyl group may be a straight chain or a branched chain.

[0031] Specific examples of the compound of the present invention include compounds having the structures shown below (in each formula, Me represents a methyl group), but are not limited thereto. [ka]

[0032] The compounds of the present invention represented by the above formulas (Ia) and (Ib) may exist as salts. Examples of such salts include base addition salts, acid addition salts, and amino acid salts. Examples of base addition salts include metal salts such as sodium salts, potassium salts, calcium salts, and magnesium salts, ammonium salts, and organic amine salts such as triethylamine salts, piperidine salts, and morpholine salts. Examples of acid addition salts include mineral acid salts such as hydrochloride, sulfate, and nitrate, and organic acid salts such as carboxylate, methanesulfonate, paratoluenesulfonate, citrate, and oxalate. Examples of amino acid salts include glycine salts. However, the salts are not limited to these salts.

[0033] The compound of the present invention may have one or more asymmetric carbons depending on the type of the substituent, and may have stereoisomers such as optical isomers or diastereoisomers. Pure stereoisomers, any mixture of stereoisomers, racemates, etc. are all included in the scope of the present invention.

[0034] In addition, the compound of the present invention or a salt thereof may exist as a hydrate or solvate, and all of these substances are included in the scope of the present invention. The type of solvent that forms the solvate is not particularly limited, and examples of solvents that can be mentioned include water, ethanol, acetone, isopropanol, etc.

[0035] In the Examples of this specification, the production methods for representative compounds included in the compounds of the present invention are specifically shown, so that a person skilled in the art can easily produce any compound included in formulas (Ia) and (Ib) by referring to the disclosure of this specification and by appropriately selecting starting materials, reagents, reaction conditions, etc. as necessary. Typically, as shown in the Examples, a compound having an azobenzene-like skeleton as a starting material is reacted with a halogenated boric acid compound, and then R 1 Or R 2 The compound of the present invention can be obtained by appropriately introducing a substituent corresponding to the following:

[0036] 2. Pharmaceutical compositions containing the compounds of the present invention The compound of the present invention can catalyze the oxygenation reaction of pathogenic amyloid. The oxygenation reaction proceeds by adding oxygen atoms to amino acid residues in amyloid and oxidizing them by exciting the compound of the present invention with light irradiation. This makes it possible to inhibit and reduce the aggregation of pathogenic amyloid.

[0037] Therefore, in another aspect, the present invention relates to an oxygenation catalyst for pathogenic amyloid or an agent for inhibiting the aggregation of pathogenic amyloid, comprising the above-mentioned compound or a salt thereof. Furthermore, the present invention also relates to a pharmaceutical composition containing the above-mentioned compound or a salt thereof and a pharma- ceutically acceptable carrier.

[0038] The compound of the present invention is characterized by its excellent oxygenation activity against aggregated pathogenic amyloid. Although not necessarily bound by theory, as shown in the above formulas (Ia) and (Ib), the compound has a structure in which an azobenzene-like skeleton and boron are complexed, and therefore, in a single molecule state, the molecular structure is bent and the excited state is alleviated even when irradiated with excitation light. On the other hand, when the compound binds to aggregated amyloid and is in a dense intermolecular environment, the molecular structure change is suppressed, and singlet oxygen is generated, which can selectively oxygenate amyloid.

[0039] "Pathogenic amyloids" include, but are not limited to, amyloids such as amyloid beta (Aβ) peptide, amylin, transthyretin, α-synuclein, tau protein, and huntingtin, which are known to be involved in Alzheimer's disease, Parkinson's disease, diabetes, Huntington's disease, and systemic amyloidosis in animals, including humans.

[0040] For example, when Aβ peptide is oxidized by the compound of the present invention, it is sufficient that one or more of the 40 or 42 amino acid residues constituting the Aβ peptide are oxidized, but it is preferable that one or more amino acid residues selected from His and Met are oxidized. The oxidation is more preferably in the form of a hydroxyl group or an oxo group (oxide) being added to each amino acid residue. In the case of His, the oxidized form of the amino acid residue is presumed to have a structure in which the imidazole ring of the histidine residue is oxidized, that is, a dehydroimidazolone ring or a hydroxyimidazolone ring. In addition, in the case of Met, it is presumed that oxygen is added to the sulfur atom in the methionine residue.

[0041] The compound of the present invention preferably has a maximum absorption wavelength (λmax) in the range of 550 to 800 nm, and preferably can be excited at that wavelength. By having an absorption band on the long wavelength side, it can be excited by long wavelength light that has high biological permeability.

[0042] Moreover, the compound of the present invention preferably has a molecular weight of 300 to 550. By having such a relatively small molecular weight, it is possible to exhibit excellent permeability through the blood-brain barrier.

[0043] The pharmaceutical composition containing the compound of the present invention or its salt can be prepared by selecting an appropriate formulation according to the administration method, and using a pharma- ceutical acceptable carrier by various preparation preparation methods. Examples of the dosage form of the pharmaceutical composition containing the compound of the present invention as the main ingredient include tablets, powders, granules, capsules, liquids, syrups, elixirs, oily or aqueous suspensions, etc., as oral preparations.

[0044] Injectables may contain stabilizers, preservatives, and solubilizing agents, and a solution that may contain these agents may be placed in a container and then freeze-dried or otherwise processed into a solid preparation to be prepared just before use. A single dose may be placed in one container, or multiple doses may be placed in one container.

[0045] Examples of topical preparations include liquids, suspensions, emulsions, ointments, gels, creams, lotions, sprays, and patches.

[0046] Solid preparations contain pharma- ceutically acceptable additives together with the compound of the present invention, such as fillers, extenders, binders, disintegrants, dissolution promoters, wetting agents, lubricants, etc., which can be selected and mixed as necessary to prepare a formulation. Liquid preparations include solutions, suspensions, emulsions, etc., and may contain suspending agents, emulsifiers, etc. as additives.

[0047] When the compound of the present invention is used as a pharmaceutical for human use, the daily dose for an adult is in the range of 1 mg to 1 g, preferably 1 mg to 300 mg.

[0048] In a further aspect, the present invention also relates to a method for preventing or treating a disease associated with pathogenic amyloid, which comprises administering an effective amount of the compound or a salt thereof. The method preferably includes irradiating the affected area of ​​a patient with light from outside the body after administration of the compound or a salt thereof. As described above, the compound of the present invention can be excited by long-wavelength light that has high biological permeability, so that the aggregation and toxicity of pathogenic amyloid in a living body (such as in the brain) can be suppressed or reduced by a non-invasive method of irradiating the patient with light from outside the body after administration such as intravenous administration.

[0049] Specifically, the compound of the present invention or a salt thereof may be introduced into a living body or a cell, and light may be irradiated when the compound reaches the target site. Examples of the administration method into a living body include intramuscular injection, intravenous injection, topical administration, and oral administration.

[0050] Diseases associated with pathogenic amyloid include Alzheimer's disease, Parkinson's disease, diabetes, Huntington's disease, systemic amyloidosis, etc. in animals including humans. Typically, the disease associated with pathogenic amyloid is Alzheimer's disease. EXAMPLES

[0051] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0052] 1. Synthesis of the Compounds of the Invention A compound of the present invention ("Compound 2") was synthesized by the following procedure.

[0053] [Synthesis of compound 1]: [ka]

[0054] To a solution of (E)-6,6'-(diazene-1,2-diyl)bis(3-bromophenol) (30 mg, 0.081 mmol, 1.0 equiv.) in THF (3.0 mL), CF3BF3K (57 mg, 0.32 mmol, 4.0 equiv.), TMSOTf (97.2 μL, 0.53 mmol, 6.7 equiv.), and DIPEA (68.8 μL, 0.40 mmol, 5.0 equiv.) were added, and the mixture was stirred at 60 °C overnight. After cooling, the mixture was concentrated and dissolved in CHCl and H2O. The mixture was extracted three times with CHCl, and the organic layer was washed with brine, dried over NaSO4, and concentrated. The resulting residue was purified by column chromatography on silica (hexane / CHCl= 3 / 1) to give compound 1 as a red solid (16.8 mg, 0.037 mmol, 46% yield). 1H NMR (CDCl3, 500MHz):δ= 7.70 (d, J = 4.5 Hz, 1H), 7.66 (d, J = 8.6 Hz, 1H), 7.42 (m, 2H), 7.33 (m, 1H), 7.26 (m, 1H); 13 C NMR (CDCl3, 126 MHz):δ= 162.1, 144.8, 139.3, 134,5, 132.7, 132.5, 132.4, 126.7, 126.3, 123.2, 119.9, 117.7; 11 B NMR (CDCl3, 126 MHz):δ= 0.30, 19 F NMR (CDCl3, 369 MHz):δ= -73.6.

[0055] [Synthesis of compound 2]: [ka]

[0056] To a solution of compound 1 (17 mg, 0.038 mmol, 1.0 equiv.) in 1,4-dioxane (0.50 mL), N,N,N'-trimethyl-1,3-propanediamine (5.6 μL, 0.038 mmol, 1.0 equiv.) was added, and the mixture was stirred at 100 °C for 1 h. After the reaction, the mixture was concentrated and dissolved in MeCN. Purification by HPLC gave compound 2 as a purple solid (13.1 mg, 0.0219 mmol, 58% yield as TFA salt). 1H NMR (CDCl3, 400MHz): δ = 7.54 (d, J = 9.6 Hz, 1H), 7.45 (d, J = 8.7 Hz, 1H), 7.25 (d, J = 1.4 Hz,1H), 7.12 (dd, J = 8.7 Hz, 1.4 Hz, 1H), 6.59 (dd, J = 9.6 Hz, 2.7 Hz, 1H), 6.25 (d, J = 2.7 Hz,1H), 3.65 (m, 2H), 3.21 (s, 3H), 3.09 (t, J = 8.2 Hz, 2H), 2.84 (s, 6H), 2.17 (quin, J = 8.2Hz, 2H); 13 C NMR (CDCl3, 99 MHz):δ = 158.1, 157.7, 149.5, 135.2, 135.1, 133.4, 125.4, 124.5, 118.1, 115.5, 109.6, 98.9, 54.8, 49.9, 43.0, 39.1, 23.0; 11 B NMR (CDCl3, 126 MHz):δ = 0.31, 19 F NMR (CDCl3, 369 MHz):=δ-74.6 (3F), -75.1 (3F); [M+H] + 485.1, found 484.9

[0057] As a comparative example, R 2 A compound not having a bromine atom at the position was synthesized. [ka]

[0058] To a solution of compound 2 (7.9 mg, 0.016 mmol, 1.0 equiv) in tBuOH (1.0 mL) was added HCOK (6.8 mg, 0.081 mmol, 5.0 equiv) and Pd(PPh) (5.7 mg, 0.0049 mmol, 0.3 equiv) and the solution was freeze-degassed three times. The mixture was then heated at 90 °C for 1 h. Volatiles were removed under reduced pressure. The resulting residue was dissolved in MeCN and purified by HPLC to give Comparative Example 1 as a purple solid (1.5 mg, 0.0029 mmol as the TFA salt, 18% yield). 1 H NMR (CD3CN, 500MHz): δ = 7.58-7.54 (m, 2H), 7.31 (dt, J = 8.0 Hz, 1.1 Hz, 1H), 7.03 (m, 2H), 6.78 (dd, J = 9.2 Hz, 2.3 Hz, 1H), 6.39 (d, J = 2.3 Hz, 1H), 3.66-3.59 (m, 2H), 3.20 (s, 3H), 3.07 (m, 2H), 2.76 (s, 6H), 2.06 (m, 2H); 13 C NMR (CDCl3, 126 MHz): δ= 158.2, 157.3, 149.3, 135.0, 134.8, 134.2, 132.4, 121.2, 114.9, 114.8, 109.1, 98.9, 55.0, 49.8, 43.1, 39.0, 23.1; 11 B NMR (CDCl3, 126 MHz):δ = -0.31, 19 F NMR (CDCl3, 369 MHz):δ= -74.4 (3F), -75.2 (3F); LRMS (ESI): m / z calcd for [M+H] + 407.2, found 407.0

[0059] 2. Oxidation of amyloid beta (Aβ) First, Aβ1-42 was prepared in situ from 26-O-acylisopeptide (commercially available from Peptide Institute, Inc.) according to the reference (Taniguchi, A.; Sasaki, D.; Shiohara, A.; Iwatsubo, T.; Tomita, T.; Sohma, Y.; Kanai, M. Angew. Chem. Int. Ed. 2014, 53, 1382).

[0060] As described in the above reference, Aβ1-42 isopeptide (200 μM in 0.1% aqueous trifluoroacetic acid), angiotensin IV (200 μM in water), [Tyr 8 ]-Substance P (200 μM in water), leuprorelin acetate (200 μM in water), and somatostatin (200 μM in water) were diluted in 100 mM phosphate buffer or phosphate-buffered saline (PBS; pH 7.4) to a final peptide concentration of 20 μM (pH 7.4). For Aβ1-42, the solutions were incubated at 37 °C for 3 h.

[0061] Compound 2 or Comparative Example 1 (2 mM in dimethyl sulfoxide) was added to each solution. The mixture containing Compound 2 (or Comparative Example 1) at a final concentration of 40 μM was irradiated with a light-emitting diode (LED) (λ = 595 nm) at 37 °C. The output of the 595 nm LED light source was 10 mW, and the light irradiation was performed at a distance of about 5 cm from the sample. A corresponding reaction sample without light irradiation was also prepared as a control. The reaction was monitored and analyzed using MALDI-TOF MS. If necessary, the reaction solution was desalted with ZipTip U-C18 (Millipore Corporation) before MS analysis. The degree of oxygenation is shown as the oxygenation intensity ratio (%) = (sum of MS peak intensities of n [O] adducts) / (sum of MS peak intensities of remaining starting material and n [O] adducts) x 100. Figure 1 shows the obtained MALDI-TOF MS spectrum. Figure 2 shows the amount of oxygenated Aβ produced.

[0062] As shown in Figure 2, it was found that the oxygenation reaction of aggregated Aβ proceeded smoothly by irradiation with 595 nm light. In addition, the results of evaluating selectivity using off-target peptides containing tryptophan, tyrosine, histidine, methionine, etc. are shown in Figure 3. As a result, under conditions in which the reaction proceeded with a 73% yield with Aβ, the yield remained below 4% with other peptides, indicating that compound 2 promotes the oxygenation reaction of Aβ with high selectivity.

[0063] In addition, a comparison of the Aβ oxygenation reaction between Compound 2 and Comparative Example 1 is shown in FIG. 4. As a result, R 2 Compound 2 having a bromine atom at position R 2 It was found that the oxygenation activity was significantly higher than that of Comparative Example 1, in which the position of the catalyst was a hydrogen atom. Note that "Cont" in the figure shows the results when only light was irradiated without adding a catalyst.

[0064] 3. Oxygenation of other amyloids Photooxygenation was also carried out in the same manner as in 2. above on amylin, α-synuclein, and insulin, which are amyloids with a cross-β-sheet structure. As a result, oxygenation proceeded even on these aggregated peptides, suggesting that compound 2 recognizes and reacts with the cross-β-sheet structure.

[0065] 4. Analysis of the excited state of compound 2 Next, the mechanism of the excited state of compound 2 was investigated. Figure 5(A) shows the results of measuring the change in the fluorescence spectrum of compound 2 in the presence and absence of aggregated Aβ. As a result, it was revealed that compound 2 exhibits fluorescence only in the presence of aggregated Aβ. Furthermore, it was confirmed that singlet oxygen is generated only in the presence of aggregated Aβ. These results suggest that the binding of compound 2 to aggregated Aβ promotes the generation of singlet oxygen via fluorescence emission and intersystem crossing.

[0066] To investigate the structural cause of this behavior, the structures of compound 2 in the ground and excited states were optimized using density functional theory (DFT) calculations. As shown in Figure 5(B), in the ground state, the dihedral angle of the CNNC of the azobenzene structure is 164°. o In the excited state, the dihedral angle is 149. o It was predicted that the structure of compound 2 is slightly bent. These results suggest that this bent structure is involved in the relaxation of the excited state of compound 2 in solution, and that compound 2 binds to aggregated Aβ, suppressing its movement and thereby exerting Aβ-selective oxygenation activity.

[0067] 5. Identification of Oxygenation Sites Glu-C (Sigma, 1 / 50 volume) dissolved in water was added to the oxygenation reaction mixture in step 2 above, incubated at 37°C for 12-16 hours, and the oxygenation sites in Aβ were analyzed using LC / MS / MS. As shown in Figure 6, it was confirmed that oxygenation occurred at the positions of histidine and methionine residues.

[0068] 6. Examination of Aβ aggregation inhibitory effect To verify the inhibitory effect of compound 2 on Aβ aggregation, a thioflavin-T assay was performed. The assay was performed as described in the above reference, with the reaction mixture (10 μL) (20 μM Aβ species, 2 μM compound 2, 0.1 M phosphate) added to a 1.25 μM thioflavin-T solution (400 μL). The thioflavin-T solution used was prepared by adding a 50 μM thioflavin-T aqueous solution (10 μL, ThT was purchased from Sigma-Aldrich, Inc.) to a 50 mM glycine-NaOH buffer (396 μL, pH 8.5). The fluorescence intensity of the solution (400 μL) was measured at room temperature with an excitation wavelength of 440 nm and an emission wavelength of 480 nm. The fluorescence intensity was measured with a spectrofluorophotometer RF-5300PC (Shimadzu Corporation) using a rectangular quartz cell (3 mm path length). As a fluorescence standard, 50 μM calcein in 100 mM phosphate buffer (pH 7.4) (400 μL, calcein purchased from Dojindo Laboratories) was used.

[0069] As a result, as shown in Figure 7, the inhibition of Aβ aggregation was confirmed by the photooxygenation reaction of Compound 2 by light irradiation. In Figure 7, "Cat" means Compound 2, and "Light" means light irradiation.

[0070] 7. Blood-brain barrier (BBB) ​​permeability Using mice, the amount present in the brain after intravenous administration of the catalyst was evaluated, and the BBB permeability of compound 2 was measured. In addition, as a comparative example, the same measurement was performed for compounds 3 and 4, which are conventional photooxygenation catalysts. Compound 3 is a compound disclosed in Non-Patent Document 2 (Ni, J. et al., Chem 2018, 4, 807-820), and compound 4 is a compound disclosed in Non-Patent Document 3 (Suzuki, T. et al., Chem. Commun. 2019, 55, 6165).

[0071] As a result, as shown in FIG. 8, compound 2 of the present invention exhibited a sufficiently high BBB permeability compared to the conventional compounds 3 and 4, and 1.55% of the administered amount was recovered from the brain 60 minutes after administration.

[0072] 8. In vivo photooxygenation reaction Compound 2 was administered to Alzheimer's disease model mice and exposed to light from outside the body to evaluate the oxygenation activity of compound 2. Compound 2 (1.0 mM, 0.2 mL, 10% DMSO, 15% Kolliphor EL, and 75% 1 * PBS) was administered intravenously to the mice. After 60 minutes, the mice were irradiated with 600 nm LED light for 10 minutes. This procedure was repeated five times over five days, and samples derived from the mouse hippocampus were evaluated by Western blotting.

[0073] The results are shown in Figure 9. As a result, in the mice administered the catalyst and exposed to light (lanes 1-3), a dimer, which is thought to be a product of oxygenation, was strongly detected compared to the mice administered only the catalyst (lanes 4-6). This result indicates that compound 2 promotes the photooxygenation of Aβ in an in vivo system.

Claims

1. A compound represented by the following formula (Ia) or (Ib) or a salt thereof: 【Chemistry 1】 (wherein X and Y are both benzene rings; R １ is a group represented by the following formula (a) and may be present at any position on X or Y: 【Chemistry 2】 In formula (a), the dashed line indicates a connection to X or Y; R 4 is a hydrogen atom, an optionally substituted alkyl group, or an aromatic ring; R 5 may be the same or different and each independently is a hydrogen atom, an optionally substituted alkyl group, or an aromatic ring; n is an integer of 0 to 5; R ２ is a halogen atom and may be present at any position on Y or X; and R ３ is a halogen atom or a haloalkyl group having 1 to 3 carbon atoms.

2. The compound according to claim 1, represented by the following formula (IIa) or (IIb), or a salt thereof: 【Chemistry 2】 (In the formula, R １ , R ２ , and R ３ is defined as in claim 1).

3. R ２ The compound or salt thereof according to claim 1 or 2, wherein is a bromine atom or an iodine atom.

4. R ３ The compound or salt thereof according to any one of claims 1 to 3, wherein is a fluorine atom or a fluoroalkyl group having 1 to 3 carbon atoms.

5. A compound or a salt thereof selected from the group consisting of: 【Chemistry 4】 (In the formula, Me represents a methyl group.)

6. A catalyst for the oxygenation of pathogenic amyloid, comprising the compound according to any one of claims 1 to 5 or a salt thereof.

7. An agent for inhibiting pathogenic amyloid aggregation, comprising the compound according to any one of claims 1 to 5 or a salt thereof.

8. A pharmaceutical composition comprising the compound according to any one of claims 1 to 5 or a salt thereof and a pharma- ceutically acceptable carrier.

9. The pharmaceutical composition according to claim 8, which is a preventive or therapeutic drug for a disease associated with pathogenic amyloid.

10. The pharmaceutical composition of claim 9, wherein the pathogenic amyloid-associated disease is Alzheimer's disease.

11. Use of the compound or a salt thereof according to any one of claims 1 to 5 for the manufacture of a prophylactic or therapeutic agent for a disease involving pathogenic amyloid.

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