JP2021102593A - New compound imaging tau - Google Patents

Abstract

To provide a compound having high specificity and selectivity to tau protein, namely, not binding to monoamine oxidase or the like, but capable of imaging selectively tau protein with excellent sensibility and contrast.SOLUTION: There is provided a pharmaceutical composition or a diagnostic composition containing a compound such as a compound shown by a following manufacturing method, a pharmaceutically acceptable salt or solvate thereof, or a compound labeled with radionuclides, a pharmaceutically acceptable salt or solvate thereof.SELECTED DRAWING: Figure 1

Description

The present invention relates to selective tau imaging probes. Specifically, the present invention relates to an imidazole [1,2-a] pyridineamine compound derivative, a pharmaceutical composition for diagnostic imaging containing the labeled compound, and a diagnostic imaging method using the labeled compound. Regarding.

Alzheimer's disease is the leading cause of dementia and is increasing with the aging of the population. Currently available therapeutic agents for Alzheimer's disease are symptomatic agents such as cholinesterase inhibitors and NMDA receptor antagonists, and there is no therapeutic agent capable of suppressing the progression of the disease.
The neuropathological features of Alzheimer's disease are amyloid plaque and neurofibrillary tangles in the brain. The former is composed mainly of amyloid β protein and the latter is composed of tau protein. Accumulation of these proteins is thought to lead to neuronal cell death and synaptic dysfunction, leading to cognitive dysfunction.

In the development of a fundamental therapeutic agent for Alzheimer's disease, a biomarker for detecting the accumulation of the above protein in the brain at the initial stage of the disease and monitoring the amount of the protein accumulated in the brain is required. Advances in molecular imaging technology using Positron Emission Tomography (PET) have enabled non-invasive imaging of amyloid β protein (amyloid PET). ^[11 C] PiB was initially developed as a radiopharmaceutical (PET probe) used for amyloid PET, and has been widely used mainly for research purposes. ^{In addition, drugs labeled with [18} F], which has a half-life longer than 11C (Flutemetamol, Fluoretapir, Fluorbetaben), have also been developed and introduced into clinical diagnosis.

Abnormal findings in amyloid PET are also frequently observed in elderly people with normal cognitive function. It is thought that there is a long interval of about 15 to 20 years from the start of accumulation of amyloid β protein in the brain to the appearance of clinical symptoms. Therefore, it is difficult to predict when the elderly will develop dementia with the amyloid PET examination alone. For accurate prognosis, it is necessary to track pathological changes after the accumulation of amyloid β protein.

The accumulated amount of amyloid β protein reaches a saturated state when dementia symptoms become apparent. Therefore, in order to accurately grasp the severity of patients after the onset of dementia, an index more strongly related to neurodegeneration is required instead of amyloid PET. Past pathological studies have shown that the intensity of neurodegeneration does not correlate with the accumulation of amyloid β protein and is closely related to the accumulation of tau protein. Therefore, bioimaging of tau protein is suitable for the purpose of accurately predicting the prognosis of patients with dementia and assessing its severity.

Clinical trials of anti-amyloid drugs have been conducted based on the amyloid hypothesis. However, the fact that even one drug has not yet been put into practical use suggests that it is difficult to control the pathological condition only by controlling the amyloid β protein. Tau protein is considered to be a factor that links the accumulation of amyloid β protein with neurodegeneration. Accumulation of amyloid β protein is thought to accelerate the progression of tau lesions from the medial temporal lobe to the cerebral cortex, leading to neurodegeneration through intracellular accumulation of tau. Tau protein is becoming more important as a therapeutic target for Alzheimer's disease in place of amyloid β, and tau imaging, which monitors the amount accumulated in the brain, plays a major role.

Neurofibrillary tangles are composed of tau protein Neurofibrillary tangles form a β-sheet structure as a secondary structure. Therefore, it has been considered that it can be detected non-invasively by a PET probe, similar to the β-sheet structure formed by amyloid β protein fibers. When a radiopharmaceutical is intravenously administered as a PET probe, the concentration of the compound reaching the brain in the brain is in the nanomolar concentration range. Therefore, a compound having high binding affinity and selectivity for tau protein fibers in the same concentration range is suitable as a probe.

Ten years after amyloid PET, multiple tau PET probes that image neurofibrillary tangles have been developed and are being evaluated clinically. The present inventors have found quinoline derivatives and benzimidazole derivatives as a group of fluorescent compounds having excellent stainability on tau protein lesions in patients with Alzheimer's disease, and have used quinoline derivatives as seeds to optimize binding to PHF tau and pharmacokinetics. We ^{have developed probes such as [18} F] THK5105, [ ¹⁸ F] THK5117, and [ ¹⁸ F] THK5351 (Patent Document 1, Non-Patent Documents 1 to 3, etc.). In addition, Kolb et al. Of Siemens broadly screened peripheral compounds of quinoline derivatives and benzimidazole derivatives, and succeeded in developing pyridoindole derivatives T807 and T808 as compounds having excellent binding selectivity to tau protein (non-patent documents). 4-6). From the results of clinical studies, T807, which has less defluorination and excellent visualization performance of lesions, has been selected as the final compound, and has been renamed to AV1451 and further to Flortaucipir, and clinical evaluation is underway. The NIRS Higuchi et al have broad binding to various tau pathology develops ^{[11 C]} PBB3 and ^{18 F-labeled} body, and advances the clinical application (Non-Patent Document 7). ^[18 F] RO6598948 developed by Roche is developed based on the chemical structure of T807, and its dynamic performance is improved by increasing water solubility (Non-Patent Document 8). ^[18 F] GTP1 developed by Genentech is a probe developed based on the chemical structure of T808, and has been improved so as to attenuate the defluorination observed in T808 (Non-Patent Document 9). ^[18 F] MK-6240 developed by Merck & Co., Ltd. has few off-target bindings, which will be described later, and can obtain an image having an extremely high SN ratio (Patent Document 3, Non-Patent Document 10). ^{Further, [18} F] PI-2620 developed by Pyramal Co., Ltd. is ^{also said to have less off-target binding like [18} F] MK-6240 (Patent Document 2 and Non-Patent Document 11). JNJ-067 developed by Janssen Pharma is also a tau-binding probe developed for the purpose of improving pharmacokinetics (Patent Document 4, Non-Patent Document 12). Some structures of each of the above compounds are shown below for reference.

Many of the early developed tau PET probes have off-target binding that does not derive from binding to tau protein. This is an obstacle to utilizing tau imaging as a biomarker for tau. THK5351 has strong binding in the basal ganglia in the absence of tau lesions, which is due to binding to monoamine oxidase B. When PET examination is performed before and after administration of selegiline, which is a monoamine oxidase B inhibitor, the binding of THK5351 is significantly reduced after administration of selegiline (Non-Patent Document 13). It is thought that it has an effect. Further, the binding of AV-1451 is not affected by the monoamine oxidase B inhibitor (Non-Patent Document 14), but it has been clarified that it binds to monoamine oxidase A (Non-Patent Document 15).

Although the THK5351 also has binding property to tau, it also has binding property to monoamine oxidase B. That is, binding selectivity to tau is low. In addition, monoamine oxidase B has a higher expression level in the brain than tau, and therefore requires higher binding selectivity and affinity. Similarly, AV1451 also has binding to monoamine oxidase A. Therefore, in order to quantify tau, it is necessary to eliminate binding to other targets such as monoamine oxidase (off-target binding) and develop a probe that exhibits binding specific to tau.

International Publication No. 2012-057312 International Publication No. 2018-015549 International Publication No. 2018-0071412 International Publication No. 2018-0155307 Okamura N, et al. : Novel 18F-labeled arylquinoline derivatives for nononive imagining of tau pathology in Alzheimer's disease. J Nucl Med. 2013 Aug; 54 (8): 1420-7. Harada R, et al. : [18F] THK-5117 PET for assisting neurofibrillary pathology in Alzheimer's disease. Eur J Nucl Med Mol Imaging. 2015 Jun; 42 (7): 1052-61. Harada R, et al. : 18F-THK5351: A novel PET radiotracer for imaging neurofibrillary pathology in Alzheimer's disease. J Nucl Med. 2016 Feb; 57 (2): 208-14. Chien DT, et al. : Early clinical PET imaging results with the novel PHF-tau radioligand [F-18] -T807. J Alzheimers Dis. 2013; 34 (2): 457-68. Xia CF, et al. : [18F] T807, a novel tau positron emission tomography imaging agent for Alzheimer's disease. Alzheimers Dement. 2013 Nov; 9 (6): 666-76. Chien DT, et al. : Early clinical PET imaging results with the novel PHF-tau radioligand [F18] -T808. J Alzheimers Dis. 2014; 38 (1): 171-84. Maruyama M, et al. : Imaging of tau pathology in a tauopathy model and in Alzheimer's patients competed to normal controls. Neuron. 2013 Sep 18; 79 (6): 1094-108. Gobbi LC, et al. : Identity of Three Novel Radiotracers for Imaging Aggregated Tau in Alzheimer's Disease with Positron Emission Tomography. J Med Chem. 2017 Sep 14; 60 (17): 7350-7370. Sanabria Bohorquez (with an acute accent on the fourth letter o) S, et al. : [18F] GTP1 (Genentech Tau Probe 1), a radioligand for detecting neurofibrillary tangle tau pathology in Alzheimer's disease. Eur J Nucl Med Mol Imaging. 2019 Sep; 46 (10): 2077-2089. Walji AM, et al. : Discovery of 6- (Fluoro- (18) F) -3- (1H-pyrrolo [2,3-c] pyridin-1-yl) isoquinoline-5-amine ([(18) F] -MK-6240) : A Positron Emission Tomography (PET) Imaging Agent for Fluorination of Neurofibrillary Targets (NFTs). J Med Chem. 2016 May 26; 59 (10): 4778-89. Seibyl J, et al. : First in human characterization of PI-2620, a next generation PET tracer for assessing tau in Alzheimer's disease and tauopathy. In: International Convention of Alzheimers and Parkinson's Disease. 2017 pp. 224. Kolb HC, et al. : PRE-CLINICAL CHARACTERIZATION OF THE NOVEL TAU PET LIGAND [18F] -JNJ'067. Alzheimer's and Dementia. 2017 July; 13 (7): P1069. Ng KP, et al. : Monoamine oxidase B inhibitor, selegiline, reduces 18F-THK5351 uptake in the human brain. Alzheimers Res Ther. 2017 Mar 31; 9 (1): 25 Hansen AK, et al. : MAO-B Inhibitors Do Not Block In Vivo Flortaucipir ([18F] -AV-1451) Binding. Mol Imaging Biol. 2018 Jun; 20 (3): 356-360 Hosteller ED, et al. : Preclinical characterization of 18F-MK-6240, a Promising PET Tracer for In vivo Neurofibrillary Tangles. J Nucl Med. 2016 Oct; 57 (10): 1599-1606.

An object of the present invention is to provide a compound having high specificity and selectivity for tau protein, that is, a compound capable of selectively imaging tau protein with good sensitivity and contrast without binding to monoamine oxidase or the like. And.

As a result of intensive studies in view of the above problems, the present inventors have high specificity and selectivity for tau protein, and they do not or hardly bind to monoamine oxidase, white matter components, etc. We have found a compound that has and can visualize tau protein with good sensitivity. We have also found a compound that can be used as a precursor of the compound. As a result, the present inventors have completed the present invention.

一般式（Ｉ−２）

一般式（Ｉ−３）

または一般式（Ｉ−４）

［各一般式中、
Ｘは、炭素（ＣＨ）または窒素（Ｎ）であり、
Ｒ^１、Ｒ^２およびＲ^３は、それぞれ独立して、水素、ハロゲン、低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲンおよびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）、−Ｏ−低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲンおよびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）または

であり、 環Ｙはアゼチジン環、ベンゼン環またはピリジン環を表し、
Ｒ^４は、ハロゲン、低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲンおよびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）、または−Ｏ−低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲンおよびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）であり、
Ｒ^１〜Ｒ^４は、何れか少なくとも１つがハロゲン、低級アルキル基（該アルキル基は、少なくとも１つのハロゲンで置換されている）、または−Ｏ−低級アルキル基（該アルキル基は、少なくとも１つのハロゲンで置換されている）である］
で示される化合物またはその医薬上許容される塩もしくは溶媒和物。That is, the present invention provides the following.
(1) General formula (I-1)

General formula (I-2)

General formula (I-3)

Or general formula (I-4)

[In each general formula,
X is carbon (CH) or nitrogen (N),
R ¹ , R ² and R ³ are independently substituted with hydrogen, halogen and lower alkyl groups, respectively (the alkyl groups are independently substituted with one or more substituents selected from halogen and hydroxy groups, respectively. (May be), -O-lower alkyl group (the alkyl group may be independently substituted with one or more substituents selected from halogen and hydroxy groups) or

The ring Y represents an azetidine ring, a benzene ring or a pyridine ring.
R ⁴ is halogen, lower alkyl group (the alkyl group each independently may be substituted with one or more substituents selected from halogen and hydroxy group), or -O- lower alkyl group (The alkyl groups may be independently substituted with one or more substituents selected from halogen and hydroxy groups).
In R ^{1 to} R ⁴ , at least one of them is a halogen, a lower alkyl group (the alkyl group is substituted with at least one halogen), or an -O- lower alkyl group (the alkyl group is at least one). It is replaced with halogen)]
A compound represented by (1) or a pharmaceutically acceptable salt or solvate thereof.

として示される、（１）に記載の化合物またはその薬学的に許容される塩もしくは溶媒和物。
（６）放射性核種により標識された（１）〜（５）の何れかに記載の化合物、またはその薬学的に許容される塩もしくは溶媒和物。
（７）放射性核種が^３Ｈ、^１１Ｃ、^１４Ｃ、^１８Ｆ、^１２３Ｉ、^１２４Ｉまたは^１２５Ｉである、（６）に記載の化合物またはその薬学的に許容される塩もしくは溶媒和物。
（８）放射性核種が^１８Ｆである、（７）に記載の化合物またはその薬学的に許容される塩もしくは溶媒和物。
（９）放射性核種が^３Ｈまたは^１４Ｃである、（７）に記載の化合物またはその薬学的に許容される塩もしくは溶媒和物。
（１０）（１）〜（９）の何れかに記載の化合物またはその薬学的に許容される塩もしくは溶媒和物を含有する、医薬組成物。(2) The compound according to (1) or a pharmaceutically acceptable salt or solvate thereof, which is represented by the general formula (I-1) and R ^{3 is hydrogen.}
(3) The compound according to (1) or a pharmaceutically acceptable salt or solvate thereof, which is represented by the general formula (I-4) and in which R ² and R ^{3 are hydrogen.}
(4) The compound according to any one of (1) to (3) or a pharmaceutically acceptable salt or solvate thereof, which comprises at least one F or I as a halogen.
(5)

The compound according to (1) or a pharmaceutically acceptable salt or solvate thereof, which is shown as.
(6) The compound according to any one of (1) to (5) labeled with a radionuclide, or a pharmaceutically acceptable salt or solvate thereof.
(7) the radionuclide is ^{3 H, 11 C, 14 C} , 18 F, 123 I, 124 I or ¹²⁵ I, a compound or a pharmaceutically acceptable salt or solvate thereof according to (6).
(8) The compound according to (7) or a pharmaceutically acceptable salt or solvate thereof, wherein the radionuclide is ^{18 F.}
(9) The compound according to (7) or a pharmaceutically acceptable salt or solvate thereof, wherein the radionuclide is ³ H or ^{14 C.}
(10) A pharmaceutical composition containing the compound according to any one of (1) to (9) or a pharmaceutically acceptable salt or solvate thereof.

(11) A composition for diagnosing conformational diseases, which comprises the compound according to any one of (1) to (9) or a pharmaceutically acceptable salt or solvate thereof.
(12) A pharmaceutical composition for treating and / or preventing conformational diseases, which comprises the compound according to any one of (1) to (9) or a pharmaceutically acceptable salt or solvate thereof.
(13) A kit for synthesizing or producing the compound according to any one of (6) to (9) or a pharmaceutically acceptable salt or solvate thereof.
(14) A composition for detecting or staining a β-sheet structural protein containing the compound according to any one of (1) to (9) or a pharmaceutically acceptable salt or solvate thereof as an essential component. A thing or kit.
(15) The kit according to (13), which is for nuclear medicine diagnostic imaging.
(16) A conformational disease in a subject, characterized in that the compound according to any one of (6) to (9), or a pharmaceutically acceptable salt or solvate thereof is administered to the subject. Diagnostic method. (17) Treatment of conformational diseases in a subject, which comprises administering to the subject the compound according to any one of (1) to (9), or a pharmaceutically acceptable salt or solvate thereof. / Or preventive measures.
(18) A β-sheet structural protein in a sample, which comprises staining the sample with the compound according to any one of (1) to (9) or a pharmaceutically acceptable salt or solvate thereof. How to detect or stain.

または

（化７〜１０中、Ｘ、Ｒ^１、Ｒ^２、Ｒ^３は（１）に定義のとおりであり、Ｚはハロゲンを表す）の化合物と

の化合物を反応させる工程を含む、（１）に記載の化合物の製造方法。(19)

Or

(In Chemical formulas 7 to 10, X, R ¹ , R ² , and R ³ are as defined in (1), and Z represents a halogen).

The method for producing a compound according to (1), which comprises a step of reacting the compound of.

または

（化１２〜１５中、Ｘ、Ｒ^１、Ｒ^２、Ｒ^３は（１）に定義のとおりである）の化合物と

（化１６中、Ｚはハロゲンを表す）
の化合物を反応させる工程を含む、（１）に記載の化合物の製造方法。(20)

Or

^{With the compounds of (X, R 1} , R ² , R ³ are as defined in (1) in Chemical formulas 12 to 15)

(Z represents halogen in Chemical formula 16)
The method for producing a compound according to (1), which comprises a step of reacting the compound of.

一般式（ＩＩ−２）

一般式（ＩＩ−３）

または
一般式（ＩＩ−４）

［各一般式中、
Ｂｏｃはｔｅｒｔ−ブトキシカルボニル基であり、
Ｘは、炭素（ＣＨ）または窒素（Ｎ）であり、
Ｒ^１、Ｒ^２およびＲ^３は、それぞれ独立して、水素、ハロゲン、ＮＯ_２、低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲン、ＮＯ_２およびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）、−Ｏ−低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲン、ＮＯ_２およびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）または

であり、 環Ｙはアゼチジン環、ベンゼン環またはピリジン環を表し、
Ｒ^４は、ハロゲン、ＮＯ_２、低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲン、ＮＯ_２およびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）、または−Ｏ−低級アルキル基（該アルキル基は、それぞれ独立して、ハロゲン、ＮＯ_２およびヒドロキシ基から選択される１個以上の置換基で置換されていてもよい）であり、Ｒ^１〜Ｒ^４は、何れか少なくとも１つがＮＯ_２、低級アルキル基（該アルキル基は、少なくとも１つのＮＯ_２で置換されている）、または−Ｏ−低級アルキル基（該アルキル基は、少なくとも１つのＮＯ_２で置換されている）である］
で示される化合物またはその医薬上許容される塩もしくは溶媒和物。(21) General formula (II-1)

General formula (II-2)

General formula (II-3)

Or general formula (II-4)

[In each general formula,
Boc is a tert-butoxycarbonyl group
X is carbon (CH) or nitrogen (N),
R ¹ , R ² and R ³ are independently selected from hydrogen, halogen, NO ₂ and lower alkyl groups (the alkyl groups are each independently _{selected from halogen, NO 2} and hydroxy groups). (May be substituted with a substituent of), an —O— lower alkyl group, each of which is independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups.} May be) or

The ring Y represents an azetidine ring, a benzene ring or a pyridine ring.
R ⁴ is a halogen, NO ₂ , lower alkyl group (the alkyl groups may be independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups), or} -O-Lower alkyl groups (each of which may be independently substituted with one or more substituents selected from _{halogen, NO 2} ^{and hydroxy groups), R 1 to} R ⁴ Is at least one of NO ₂ , a lower alkyl group (the alkyl group is _{substituted with at least one NO 2} ), or an -O- lower alkyl group (the alkyl group is at least one NO ₂₎ . Has been replaced)]
A compound represented by (1) or a pharmaceutically acceptable salt or solvate thereof.

(22) A kit for preparing the labeled compound according to any one of (6) to (9), or a pharmaceutically acceptable salt or solvate thereof, according to at least (21). A kit containing a compound or a pharmaceutically acceptable salt or solvate thereof.

INDUSTRIAL APPLICABILITY According to the present invention, a compound having high specificity and selectivity for tau protein, having central translocation property, and capable of delineating tau with good sensitivity and a precursor thereof are provided, and tau protein is selectively imaged. be able to. In particular, the compound of the present invention has an advantage that tau protein can be clearly imaged as compared with the case of using a conventional compound because of its high specificity and selectivity for tau.

Further, according to the present invention, it is possible to perform image diagnosis of conformational diseases such as tauopathy, particularly image diagnosis using PET. Therefore, the present invention enables accurate diagnosis, effective treatment and prevention of conformational diseases such as tauopathy, especially Alzheimer's disease at an early stage.

It is an autoradiograph image of the compound of this invention using the Alzheimer's disease brain section. The present invention compounds using Alzheimer camphor sections of the basal nucleus ^region, a [3 H] autoradiographic images and various immunostaining THK-5351 (IHC, Immunohistochemistry) image. It is a comparison and histopathological staining image of the autoradiograph image of the compound of this invention, various tau PET tracers, and amyloid PET tracers. The image shown by Gallyas Braak shows the localization of tau lesions. It is a result of calculating the contrast ratio of gray matter and white matter of the autoradiography image of the compound of this invention and various tau PET tracers in FIG.

Hereinafter, the present invention will be described in detail.

As used herein, the term "lower alkyl group" means a linear or branched alkyl group having 1 to 6 carbon atoms, and specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, and the like. Butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isoamyl group, neopentyl group, isopentyl group, 1,1-dimethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 1,2- Dimethylpropyl group, hexyl group, isohexyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 2,2-dimethylbutyl Group, 1,3-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1,2,2-trimethylpropyl group, 1-ethyl- 2-Methylpropyl group and the like can be mentioned.

As used herein, the term "halogen" means fluorine, chlorine, bromine, and iodine.

In the present specification, "tau protein", "tau protein", and "tau" are synonymous.

When asymmetric carbon atoms are present in the compounds of the present invention, mixtures of isomers and their individual isomers are also included in the compounds of the present invention.

Further, for example, when one asymmetric carbon is present in the compound of the present invention, the optically active compound is generally synthesized from a mixture of isomers by selectively synthesizing each compound by asymmetric synthesis. It can be separated by a known method. A commonly known method of separating from the mixture includes, for example, separating each optical isomer by column chromatography.

As described above, the compound according to the present invention is represented by the general formulas (I-1), (I-2), (I-3) or (I-4). In order to more specifically disclose the compound according to the present invention, various symbols used in each general formula will be described with reference to specific examples.

In the general formula (I-1-4), X represents carbon or nitrogen. If carbon is selected, the carbon will be accompanied by one hydrogen and CH will replace X.

である。R ¹ , R ² and R ³ are independently substituted with hydrogen, halogen and lower alkyl groups, respectively (the alkyl groups are independently substituted with one or more substituents selected from halogen and hydroxy groups, respectively. (May be), -O-lower alkyl group (the alkyl group may be independently substituted with one or more substituents selected from halogen and hydroxy groups) or

Is.

Since R ¹ , R ² and R ³ are independent of each other, they can be freely selected without being influenced by each other. For example, R ^1, R ² and R ³ are all halogen and the same, or R ¹ is hydrogen, R ² is halogen, R ³ is a lower alkyl group, and R ^{1 to} R ³ are all different. Can be mentioned. In addition, it is naturally conceivable that some of them are the same, such as when ^{R 1} and R ² are hydrogen and R ^{3 is halogen.}

Even when the lower alkyl group or the -O- lower alkyl group is substituted with a plurality of substituents selected from the halogen and hydroxy groups, the plurality of halogen and / or hydroxy groups are independent of each other and therefore affect each other. The lower alkyl group or the —O— lower alkyl group can be freely substituted without receiving.

Ring Y represents an azetidine ring, a benzene ring or a pyridine ring. The tip of the wavy line of the bond extending from the ring Y indicates the connection to the other structure of the structure.

R ⁴ is halogen, lower alkyl group (the alkyl group each independently may be substituted with one or more substituents selected from halogen and hydroxy group), or -O- lower alkyl group (The alkyl groups may be independently substituted with one or more substituents selected from halogen and hydroxy groups).

に表される結合位置が好ましく、環Ｙがピリジン環の場合は、

に表されるような結合位置が好ましい。In the formula (I-1 to 4), point of attachment to the ring Y binding position and R ⁴ to other structures ring Y is not particularly limited, when the ring Y is azetidine ring,

The bond position represented by is preferable, and when the ring Y is a pyridine ring,

The bonding position as shown in is preferable.

In the compound represented by the formula (I-1 to 4) of the present invention, ^{at least one of R 1 to} R ⁴ is a halogen and a lower alkyl group (the alkyl group is substituted with at least one halogen). ), Or -O-lower alkyl group (the alkyl group is substituted with at least one halogen). The halogen is preferably fluorine (F) or iodine (I).

The ^{group selected as R 1} , R ² and R ³ is not particularly limited as long as it is within the scope of the present invention, but when the compound of the present invention is represented by the general formula (I-1), it is not particularly limited. , R ³ is preferably hydrogen, where ^{either R 1} or R ² is a halogen, an —O-lower alkyl group (the alkyl group is substituted with at least one halogen), chemical 23 (R ^4). Is a halogen) or the ^{group shown in Chemical formula 24 (R 4} is a halogen) and R ³ is hydrogen.

Similarly, when the compound of the present invention is represented by the general formula (I-2) or the general formula (I-3), it is preferable ^{that R 1} is halogen and R ^{2 is hydrogen.}

Similarly, when the compound of the present invention is represented by the general formula (I-4), ^{it is preferable that R 2} and R ³ are hydrogen, and R ¹ is an —O— lower alkyl group (the alkyl group is It is more preferred that it is substituted with at least one halogen) and that R ² and R ^{3 are hydrogen.}

Further, it is represented by the formulas (II-1), (II-2), (II-3) and (II-4), which are precursors of the compounds of the formulas (I-1 to 4) of the present invention. In order to more specifically disclose the compounds, various symbols used in each general formula will be described with specific examples.

In the compound represented by the formula (II-1 to 4) of the present invention, X is the same as the definition in the formula (I-1 to 4) and is as described above.

Boc represents a tert-butoxycarbonyl group.

である。In the compound represented by the formula (II-1 to 4) of the present invention, R ¹ , R ² and R ³ are independently hydrogen, halogen, NO ₂ and lower alkyl groups (the alkyl groups are each). Independently, it _{may be substituted with one or more substituents selected from NO 2} , halogen and hydroxy groups), -O-lower alkyl group (the alkyl groups are independently NO ₂ , NO 2, respectively. It may be substituted with one or more substituents selected from halogen and hydroxy groups) or

Is.

In the compound represented by the formula (II-1 to 4) of the present invention, the ring Y is the same as the definition in the formula (I-1 to 4) and is as described above.

R ⁴ is a halogen, NO ₂ , lower alkyl group (the alkyl groups may be independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups), or} -O-Lower alkyl groups, each of which may be independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups.}

に表される結合位置が好ましく、環Ｙがピリジン環の場合は、

に表されるような結合位置が好ましい。In formula (II-1 to 4), point of attachment to the ring Y binding position and R ⁴ to other structures ring Y is not particularly limited, when the ring Y is azetidine ring,

The bond position represented by is preferable, and when the ring Y is a pyridine ring,

The bonding position as shown in is preferable.

In the compound represented by the formula (II-1 to 4) of the present invention, at least one of ^{R 1 to} R ⁴ is replaced with _{NO 2} , and a lower alkyl group (the alkyl group is _{substituted with at least one NO 2).} ), Or -O-lower alkyl group (the alkyl group is substituted with _{at least one NO 2).}

The ^{group selected as R 1} , R ² and R ³ is not particularly limited as long as it is within the scope of the present invention, but when the compound of the present invention is represented by the general formula (II-1). It is ^{preferable that R 3} is hydrogen, and more preferably R ¹ is a lower alkyl group, R ² is NO ₂ and R ³ is hydrogen.

Similarly, when the compound of the present invention is represented by the general formula (II-2) or the general formula (II-3), it is preferable ^{that R 1} is NO ₂ and R ^{2 is hydrogen.}

Similarly, when the compound of the present invention is represented by the general formula (II-4), ^{it is preferable that R 2} and R ³ are hydrogen, and R ¹ is an —O— lower alkyl group (the alkyl group is It is more preferred that it is substituted with at least one NO ₂ ^{) and that R 2} and R ^{3 are hydrogen.}

The compound of formula (II-1) can be used as a synthetic precursor of the compound of formula (I-1), in particular as a synthetic precursor of the labeled compound of formula (I-1). Similarly, a compound of formula (II-2) is a compound of formula (I-2), a compound of formula (II-3) is a compound of formula (I-3), of formula (II-4). The compound can be used as a synthetic precursor of the compound of formula (I-4), in particular as a synthetic precursor of each labeled compound. Wherein conversion method from (II-1 to 4) of the compound to the corresponding compound of formula (I-1 to 4) are well known to those skilled in the art, for example, first recovery easy compound ^{(18 F,} etc. (Including the labeled compound) is synthesized as a primary product, and the product is reacted with the compound of the formula (II-1 to 4) to cause the corresponding compound of the labeled / unlabeled formula (I-1 to 4). Can be synthesized. In this case, since by-products other than the target product and non-radioactive impurities are usually contained after the completion of the synthesis, it is preferable to separate the target product by high performance liquid chromatography or the like.

Salts of the compounds of the present invention are also included in the present invention. The salt can be produced according to a conventional method using the compound represented by the formula (I-1 to 4) or (II-1 to 4) provided by the present invention.

Specifically, when the compound of the above formula (I-1 to 4) or (II-1 to 4) has a basic group such as an amino group or a pyridyl group in the molecule. Can be converted to the corresponding salt by treating the compound with an acid.

Further, when the compound of the present invention has an acidic group such as a carboxyl group in the molecule, it can be converted into a corresponding salt by treating the compound with a base. can do.

Examples of acid addition salts include inorganic acid salts (for example, hydrochlorides, sulfates, hydrobromates, phosphates, etc.) and organic acid salts (for example, acetates, trifluoroacetates, succinates, maleates, etc.). Examples thereof include acid salts, fumarates, propionates, citrates, tartrates, lactates, oxalates, methanesulfonates, p-toluenesulfonates, etc.). Examples of the base addition salt include alkali metal salts, alkaline earth metal salts, ammonium salts and the like. Further, these salts may be hydrates or may exist as solvates.

Functional groups such as amino, thiol, carboxyl and hydroxy groups present in the starting compounds and precursors that are converted to the compounds of the invention by the methods described herein are optionally common in preparative organic chemistry. It may be protected by conventional protective groups. Protected amino, thiol, carboxyl and hydroxy groups are converted to free amino, thiol, carboxyl and hydroxy groups under mild conditions without disrupting the molecular backbone or causing other undesired side reactions. It can be done.

The purpose of inserting the protecting group is to protect the functional group from unwanted reactions with the reaction components under the conditions used to carry out the desired chemical conversion. The need and selection of protecting groups for a particular reaction is known to those skilled in the art, the nature of the functional groups to be protected (hydroxy, amino, etc.), the structure of the molecule in which the substituent is a part. And depends on stability and reaction conditions. For example, examples of the hydroxy group protecting group include a THP group, a methoxymethyl group, and an Ac group. The protecting group is preferably one that is eliminated under acidic conditions.

As shown in Examples, the compounds of formulas (I-1 to 4) have high specificity and selectivity for tau protein, and also have high central migration.

High specificity and selectivity for tau protein means high binding to tau protein and little or no binding to other substances, particularly amyloid β, monoamine oxidase A, monoamine oxidase B. And binding to brain white matter components with little or no binding. Whether or not coupling has occurred can be visually determined by visually recognizing the imaging image. In addition, the degree of binding can be quantitatively expressed by the contrast ratio of the image. For example, in the Alzheimer's disease brain, it is known that tau protein accumulates in the gray matter nerve cell body. Therefore, an imaging image of the Alzheimer's disease brain. By calculating the contrast ratio between gray matter and white matter using, it is possible to quantitatively investigate how much non-specific / non-selective binding to white matter occurs. Further, with respect to tau protein, amyloid β, monoamine oxidase A, and monoamine oxidase B, for example, it is possible to investigate whether or not binding has occurred by a competitive binding test using a labeled ligand.

In the competitive binding assay, for tau protein, _{IC 50} is less than 1000 nM, preferably have a binding of about less than 100nM, and amyloid beta, monoamine oxidase A, for monoamine oxidase B, _{IC 50} is 100nM It can be said that the specificity and selectivity for tau protein are high if the non-binding property is larger, preferably larger than 1000 nM.

Due to the characteristics of the compound of the present invention, the compound of the formula (I-1 to 4) can be used as a probe for the protein to diagnose tauopathy, and the compound of the formula (I-1 to 4) can be used to diagnose the tauopathy. Can be treated and / or prevented. In particular, the compounds of formulas (I-1 to 4) are suitable for image diagnosis of tauopathy, particularly image diagnosis using PET. Therefore, the compounds of formulas (I-1-4) can be used for accurate diagnosis, effective treatment and prevention of conformational diseases such as tauopathy, especially Alzheimer's disease at an early stage.

Conformational diseases are diseases characterized in that structural abnormalities of proteins are involved in the onset, and there are various diseases characterized by the deposition of insoluble fibrillar proteins in various organs and tissues in the body. These diseases include Alzheimer's disease, Prion's disease, Levy's body disease, Parkinson's disease, Huntington's disease, bulbous spinal muscle atrophy, dentate nucleus / paleosphere Louis body atrophy, spinocerebellar degeneration, Machado- joseph disease, Amyotrophic Lateral Sclerosis (ALS), down's syndrome, pick's disease, FTDP-17 (Frontotemporal Dementia and Parkinsonism linked to Chromosome 17), LNTD (Limbic neurofibrillary Tangle Dementia), Sudanophilic Leukodystrophy, include amyloidosis like. In the present invention, conformational disease preferably means a disease (tauopathy) whose main symptom is the accumulation of tau protein in the brain. Tauopathy includes Alzheimer's disease, Pick disease, progressive supranuclear palsy (PSP) and the like.

In the diagnosis of tauopathy, the compound of the present invention can be used as a probe without labeling. For example, the biopsy sample may be contacted with the compound of the present invention to check for the presence or absence of stained portions. However, it is common to use labeled compounds of the invention as diagnostic probes for tauopathy.

Labels include those using fluorescent substances, affinity substances, enzyme substrates, radionuclides, etc., and probes labeled with radionuclides are usually used for diagnostic imaging of tauopathy. The compounds of the present invention can be labeled with various radionuclides by methods well known in the art. For ^{example, 3 H, 14 C, 35} S, 131 I etc. are radionuclides which have been used previously, are often used in vitro. The general requirements for diagnostic imaging probes and their detection means are in vivo diagnostic imaging, low patient damage (particularly non-invasive), high detection sensitivity, and appropriate half-life. The length is appropriate (labeled probe preparation time and diagnosis time are appropriate). Therefore, recently, positron emission tomography (PET) using γ-rays showing high detection sensitivity and substance permeability or computed tomography (SPECT) using γ-ray emitting nuclei has come to be used. .. Of these, PET is preferable because it detects two γ-rays emitted from positron-emitting nuclides in opposite directions by a coincidence counting method with a pair of detectors, and thus provides information with excellent resolution and quantification. .. For SPECT, the compounds of the invention can be labeled with γ-ray emitting nuclides such as ^99m Tc, ¹¹¹ In, ⁶⁷ Ga, ²⁰¹ Tl, ¹²³ I, ^{133 Xe. 99 m} Tc and ¹²³ I are commonly used for SPECT. For PET, the compounds of the invention can be labeled with positron emitting nuclides such as ¹¹ C, ¹³ N, ¹⁵ O, ¹⁸ F, ⁶² Cu, ⁶⁴ Cu, ⁶⁸ Ga, ^{76 Br.} Among also positron emitting nuclides half life is appropriate from the viewpoint of the labeled ^{easiness, 11 C, 13 N, 15} O, 18 F ^, more preferably ¹⁸ F and ¹¹ C ^are the ¹⁸ F Especially preferable. As is obvious to those skilled in the art, ^{m of 99 m} Tc indicates a metastable nuclear isomer.

The labeling position of the compound of the present invention in a radionuclide such as a positron emitting nuclide or a γ-ray emitting nuclide may be any position, and for example, the compound of the present invention is labeled ^{with 18 F.} In this case, a form in which ¹⁸ F is bonded to any position of ^{R 1 to} R ^{4 is preferable.} Further, for example, when a lower alkyl group substituted with one or more substituents selected from halogens and hydroxy groups is selected as ^{R 1 to} R ^{4 , 18} F is selected as the halogen contained in the alkyl groups. You may.

The radionuclide used in the compound according to the present invention is produced by a cyclotron or a generator. Those skilled in the art can select a production method and an apparatus according to the nuclide produced. The nuclides thus produced can be used to label the compounds of the invention.

Methods for producing labeled compounds labeled with these radionuclides are well known in the art. Typical methods include chemical synthesis methods, isotope exchange methods and biosynthesis methods. The chemical synthesis method has been widely used in the past, and is essentially the same as the usual chemical synthesis method except that a radioactive starting material is used. Various nuclides have been introduced into the compound by this method. Isotope exchange method, a ^{3 H,} 35 S, 125 ^I etc. in the compounds of simple structure transferred into compounds of complex structure, is a method of obtaining a compound of complex structure labeled with these radionuclides .. The biosynthesis method is a method ^{in which a compound labeled with 14} C, ³⁵ S or the like is given to cells such as microorganisms to obtain a metabolite into which these nuclides have been introduced.

Regarding the labeling position, the labeling can be introduced at a desired position by designing a synthesis scheme according to the purpose in the same manner as in ordinary synthesis. Such designs are well known to those of skill in the art.

^{Further, for example, when positron emitting nuclides such as 11} C, ¹³ N, ¹⁵ O, and ¹⁸ F having a relatively short half-life are used, the desired nuclide is obtained from a small cyclotron installed in a facility such as a hospital, and the above It is also possible to label a desired compound at a predetermined position by the method and immediately use it for diagnosis, examination, treatment and the like.

The desired nuclide can be introduced and labeled at a desired position of the compound of the present invention by a method known to those skilled in the art. Administration of the labeled compound of the present invention to a subject may be topical or systemic. The administration route includes injection or infusion into the abdominal cavity, vein, artery, or cerebrospinal fluid, and can be selected depending on the type of disease, the nuclei used, the compound used, the condition of the subject, and the factors of the test site. The compound of the present invention can be administered as a probe, and after a sufficient time has elapsed for binding and disintegration to tau protein, the test site can be examined by means such as PET and SPECT. These means can be appropriately selected according to factors such as the type of disease, the nuclide used, the compound used, the condition of the subject, and the test site.

The dose of the compound of the present invention labeled with a radionuclide varies depending on the type of disease, the nuclide used, the compound used, the age, physical condition, sex, degree of disease, test site, and the like of the subject. In particular, it is necessary to pay sufficient attention to the exposure dose of the subject. For example, the radioactivity of the compounds of the invention labeled with positron emitting nuclides such as ¹¹ C, ¹³ N, ¹⁵ O, ^{18 F is typically 3.7 megabecquerels to 3.7 gigabecrels, preferably 18 megabecquerels to 740.} It is in the range of mega-becquerels.

The present invention provides a composition for diagnostic imaging of tauopathy, which comprises the compound of the present invention. The compositions of the invention include the compounds of the invention and pharmaceutically acceptable carriers. The compounds of the invention in the composition are preferably labeled. Although there are various labeling methods as described above, they are labeled with radionuclides (especially positron emitting nuclides such as ¹¹ C, ¹³ N, ¹⁵ O, and ^{18 F for PET) for in vivo diagnostic imaging applications.} Is desirable. The form of the composition of the present invention is preferably a form that can be injected or infused for the purpose. Therefore, the pharmaceutically acceptable carrier is preferably a liquid, and is preferably an aqueous solvent such as potassium phosphate buffer, physiological saline, Ringer's solution, distilled water, or polyethylene glycol, vegetable oil, ethanol, glycerin, dimethyl. There are, but are not limited to, non-aqueous solvents such as sulfoxide, propylene glycol and the like. The blending ratio of the carrier and the compound of the present invention can be appropriately selected depending on the application site, detection means, etc., but is usually 100,000: 1 to 2: 1, preferably 10,000: 1 to 10: It is a ratio of 1. Further, the composition of the present invention further comprises known antibacterial agents (eg, antibiotics, etc.), local anesthetics (eg, procaine hydrochloride, etc.), buffers (eg, Tris-hydrochloric acid buffer, Hepes buffer, etc.), and osmoregulators (eg, osmoregulatory agents). , Glucose, sorbitol, sodium chloride, etc.) and the like.

Furthermore, the present invention provides a kit for diagnostic imaging of tauopathy (including for diagnostic imaging of nuclear medicine) containing the compound of the present invention as an essential component. The kit contains, for example, the compounds of the present invention, solvents for dissolving them, buffers, osmotic pressure regulators, antibacterial agents, local anesthetics, etc., individually or in combination in their respective containers. It is a collection of things. The compounds of the present invention may be unlabeled or labeled. If unlabeled, the compounds of the invention can be labeled prior to use by conventional methods as described above.

Furthermore, since the compound of the present invention specifically binds to the tau protein, the tau protein in the specimen can be obtained by contacting the compound of the present invention with the sample specimen in vitro, either unlabeled or labeled. It can also be used for detection, quantification, etc. For example, the compound of the present invention may be used for tau protein staining of microscopic specimens, colorimetric quantification of tau protein in a sample, quantification of tau protein using a scintillation counter, and the like. Preparation of microscopic specimens and staining with the compounds of the present invention can be carried out by conventional methods known to those skilled in the art.

As described above, the compound of the present invention has high specificity and selectivity for tau protein. Therefore, the compound of the present invention is useful for, for example, research on tau protein-accumulating diseases or diagnosis before or after death, and is considered to be useful, for example, as a stain for neurofibrillary tangles in the brain of Alzheimer's disease patients. Staining of specimens, such as brain sections, using the compounds of the present invention can be performed by conventional methods known to those of skill in the art.

Therefore, according to the present invention, a composition for staining tau protein in a sample containing the compound of the present invention or a pharmaceutically acceptable salt or solvate thereof, and the compound of the present invention or a pharmaceutically acceptable product thereof. Kits for staining tau protein in samples are also provided, which include an acceptable salt or solvate as an essential component. Further, according to the present invention, there is also provided a method for staining tau protein in a sample, which comprises using the compound of the present invention or a pharmaceutically acceptable salt or solvate thereof. A suitable sample for these stains is a brain section.

As mentioned above, tau protein is known to be neurotoxic. Since the compound of the present invention specifically and selectively binds to tau protein, it prevents tau protein from interacting with each other to accumulate and aggregate, and suppresses its neuronal toxicity, thereby causing conformational diseases (for example, It is considered to be a therapeutic or preventive drug for (such as Alzheimer's disease).

The forms of diagnostic compositions and pharmaceutical compositions provided by the present invention, such as diagnostic agents, therapeutic agents and prophylactic agents, are not particularly limited, but liquid formulations are preferable, and injection formulations are particularly preferable. Since the compound of the present invention has high blood / brain barrier permeability as shown in Examples, the above-mentioned pharmaceutical composition can be prescribed and administered for intravenous injection or intravenous infusion. The preparation of such a liquid formulation can be carried out by a method known in the art. To prepare the solution, for example, the compound of the present invention is dissolved in a suitable carrier, water for injection, physiological saline, Ringer's solution, etc., sterilized with a filter or the like, and then filled in a suitable container, for example, a vial or ampoule. It is also possible to freeze-dry the solution and restore it to the solution again with a suitable carrier at the time of use. The preparation of the suspension can be carried out, for example, by sterilizing the compounds of the invention by exposing them to, for example, ethylene oxide, and then suspending them on a sterilized liquid carrier.

The dose of the compound of the present invention to a human subject for the purpose of diagnosing, treating, or preventing conformational diseases depends on the patient's medical condition, sex, age, body weight, etc., but is generally 70 kg in body weight. For adults, the daily dose is 0.1 mg to 1 g, preferably 1 mg to 100 mg, more preferably 5 mg to 50 mg. Treatment can be performed at a dose that takes a certain period of time, and the dose can be increased or decreased depending on the result.

The following shows typical examples of the compounds of the formulas (I-1 to 4) preferably used in the present invention.

Hereinafter, the present invention will be described in more detail with reference to production examples of the compounds of the present invention, production examples of intermediates, and test examples, but the present invention is not limited to these examples.

Preparation of Compounds of the Invention Here, all reagents used were commercially available without purification. As the medium pressure preparative liquid chromatography apparatus, an automatically set medium pressure preparative liquid chromatograph system (AI-580S) manufactured by Yamazen Corporation, HiFlash colon, and Universal color were used. The mass spectrum was measured by the EI method or the MALDI method using JEOL JMS-DX3030 (JEOL Ltd.), respectively. 1H-NMR was measured using JEOL ECA-600 (JEOL Ltd.) or Bruker AVANCE600 (Bruker), and all chemical shifts were based on tetramethylsilane (0 ppm) as an internal standard.

Method for producing compound 1

Step 1: Preparation of Compound 1-2 THF (3 mL) of Compound 1-1 (200 mg, 0.54 mmol), imidazo [1,2-a] pyridine-7-amine (108 mg, 0.81 mmol). _{) Add Pd 2} (dba) ₃ (19.5 mg, 0.02 mmol), Xant Phos (12.3 mg, 0.02 mmol) and K ₃ PO ₄ (221 mg, 1.04 mmol) to the suspension. After bubbling nitrogen for 5 minutes, the mixture was stirred at 80 ° C. for 24 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel NH2, elution solvent: ethyl acetate / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain a yellow solid compound 1-2 (crude product). 74.7 mg) was obtained.

Step 2: Preparation of Compound 1 A mixture of Compound 1-2 (74.7 mg), TBAF (0.2 mL) and THF (1 mL) was stirred at room temperature for 2 hours. After completion of the reaction, saturated brine was added and the reaction mixture was extracted with ethyl acetate. After drying over magnesium sulfate, the mixture is filtered, the filtrate is distilled off under reduced pressure, and the obtained residue is purified by flash chromatography (silica gel NH2, elution solvent: ethyl acetate / methanol 9/1) to form a white solid compound 1. (34 mg, 0.09
The total of mmol, step 1 and step 2 was 16%).
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 3.97-4.09 (3H, m), 4.43-4.60 (2H, m), 5.47 (1H, d, J = 4) .8 Hz), 6.96 (1H, d, J = 7.2 Hz), 7.05 (1H, d, J = 9.0 Hz), 7.25-7.2 9 (2H, m) , 7.36 (1H, s), 7.68-7.70 (2H, m), 8.02 (1H, d, J = 9.0 Hz), 8.35 (1H, d, J = 7) .8 Hz), 8.67 (1H, s), 9.54 (1H, s).
EI MS m / z = 352 [M] +

Method for producing compound 2

Preparation of Compound 2 In a THF (5 mL) suspension of Compound 2-1 (50 mg, 0.276 mmol), imidazo [1,2-a] pyridine-7-amine (53 mg, 0.4 mmol). , Pd ₂ (dba) ₃ (10 mg, 0.01 m mmol), Xant Phos (6.3 mg, 0.01 mmol), K ₃ PO ₄ (110 mg, 0.5 mmol) and bubbling nitrogen for 5 minutes. After that, the mixture was stirred at 80 ° C. for 15 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel NH2, elution solvent: ethyl acetate / methanol 9/1), the solvent was distilled off under reduced pressure, and compound 2 (15.8 mg, 15.8 mg, 0. 06 mmol) was obtained.
^{1 1} H NMR (600 MH _Z , DMSO-d ₆ ) δ 6.98 (1 H, d, J = 6.6 Hz), 7.12 (1 H, d, J = 9.0 Hz), 7.38 ( 1H, s), 7.49 (1H, td, J = 3.0, 9.0 Hz), 7.58 (1H, dd, J = 3.0, 9.0 Hz), 7.72 (1H) , S), 7.79 (1H, dd, J = 5.4, 8.7 Hz), 8.08 (1H, d, J = 9.0 Hz), 8.37 (1H, d, J =) 7.8 Hz), 8.68 (1H, s), 9.54 (1H, s).
EI MS m / z = 278 [M] +

Method for producing compound 3

Step 1: Preparation of Compound 3-2 2-Fluoroethyl tosylate (2-fluoroethyl tosylate) in a DMF (3 mL) suspension of Compound 3-1 (250 mg, 1.4 mmol) and potassium carbonate (684 mg, 4.9 mmol). 238 μL (1.4 mmol) was added, and the mixture was stirred at 70 ° C. for 2 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over magnesium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / n-hexane 1/4), and the solvent was distilled off under reduced pressure to prepare a white solid compound 3-2 (232 mg, 1). .0 mmol, 71%) was obtained.

Step 2: Preparation of Compound 3 Suspension of Compound 3-2 (232 mg, 1.0 mmol), imidazo [1,2-a] pyridine-7-amine (100 mg, 0.80 mmol) in THF (10 mL). To the solution _{, add Pd 2} (dba) ₃ (19.5 mg, 0.02 mmol), Xant Phos (12.3 mg, 0.02 mmol), K ₃ PO ₄ (221 mg, 1.04 mmol), and add nitrogen to 5 After bubbling for 1 minute, the mixture was stirred at 80 ° C. for 14 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silicanese NH2, elution solvent: ethyl acetate / methanol 9/1), and the solvent was distilled off under reduced pressure to give a PLC (elution solvent: chloroform / methanol 9/1). The solvent was evaporated under reduced pressure to give compound 3 (29 mg, 0.09 mmol, 11%) as a white-yellow solid.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 4.30 (2H, dt, J = 4.2, 30.6 Hz), 4.77 (2H, dt, J = 4.2, 30.6) Hz), 6.96 (1H, dd, J = 1.8, 7.8 Hz), 7.06 (1H, d, J = 9.0 Hz), 7.26 (1H, d, J = 3) .6 Hz), 7.30 (1H, dd, J = 2.4, 8.7 Hz), 7.37 (1H, s), 7.69-7.70 (2H, m), 8.01 (1H, d, J = 9.0 Hz), 8.35 (1H, d, J = 7.2 Hz), 8.67 (1H, d, J = 1.8 Hz), 9.55 (1H) , S).
EI MS m / z = 322 [M] +

Method for producing compound 4

Step 1: Preparation of Compound 4-2 2-Fluoropropyl tosylate (2-fluoropropyltosylate) in a DMF (3 mL) suspension of Compound 3-1 (233 mg, 1.3 mmol) and potassium carbonate (684 mg, 4.9 mmol). 300 mg (1.3 mmol) was added, and the mixture was stirred at 70 ° C. for 13 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over magnesium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / n-hexane 1/4), and the solvent was distilled off under reduced pressure to prepare a white solid compound 4-2 (184 mg 0.77). mmol) was obtained.

Step 2: Preparation of Compound 4 Suspension of Compound 4-2 (184 mg, 1.0 mmol), imidazo [1,2-a] pyridine-7-amine (135 mg, 0.80 mmol) in THF (10 mL). To the solution, t-BuXPhosPdG3 (61 mg, 0.08 m mmol) and t-BuONa (0.67 mL, 1.34 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silicanese NH2, elution solvent: ethyl acetate / methanol 9/1), the solvent was distilled off under reduced pressure, and further silica gel (elution solvent: chloroform / methanol 9/1) was used. The solvent was distilled off under reduced pressure to obtain Compound 4 (156.9 mg, 0.467 mmol, 60%) as a white-yellow solid.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 2.09-2.18 (2H, m), 4.14 (2H, t, J = 6.6 Hz), 4.62 (2H, dt, J = 5.4, 47.4 Hz), 6.99-7.02 (1H, m), 7.07 (1H, dd, J = 2.4, 9.0 Hz), 7.26-7 .28 (1H, m), 7.41 (1H, d, J = 4.8 Hz), 7.69 (1H, d, J = 9 Hz), 7.74 (1H, s), 8.03 (1H, d, J = 9.0 Hz) 8.38 (1H, d, J = 7.8 Hz), 8.72 (1H, d, J = 3.6 Hz), 9.66 (1H, d, J = 3.6 Hz) d, J = 17.4 Hz).
EI MS m / z = 336 [M] +

Method for producing compound 5

Step 1: Preparation of Compound 5-1 2-Fluoroethyl tosylate (2-fluoroethyl tosylate) in a DMF (3 mL) suspension of Compound 4-1 (310 mg, 1.4 mmol) and potassium carbonate (228 mg, 1.65 mmol). 238 μL (1.4 mmol) was added, and the mixture was stirred at 70 ° C. for 2 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over magnesium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / n-hexane 1/4), and the solvent was distilled off under reduced pressure to obtain compound 5-1 (121 mg, 0) as a white solid. .45 mmol, 32%) was obtained.

Step 2: Preparation of Compound 5 Suspension of Compound 5-1 (120 mg, 0.45 mmol), imidazole [1,2-a] pyridine-7-amine (87 mg, 0.65 mmol) in THF (10 mL). To the solution, t-BuXPhosPdG3 (35.7 mg, 0.045 m mmol) and t-BuONa (0.39 mL, 0.78 mmol) were added, nitrogen was bubbled for 5 minutes, and then the mixture was stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 5 (77.7 mg, 0.24) as a white-yellow solid. mmol, 53.7%) was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 4.31 (2H, dt, J = 3.0, 31.2 Hz), 4.78 (2H, dt, J = 3.6, 48.0) Hz), 6.76 (1H, d, J = 3.0, 12.0 Hz), 6.98 (1H, s), 7.14 (1H, dd, J = 2.4, 8.7 Hz) ), 7.28 (1H, d, J = 1.8 Hz), 7.33 (1H, dd, J = 1.8, 8.7 Hz), 7.37 (1H, s), 7.61 (1H, d, J = 1.2 Hz), 7.70 (1H, s), 7.76 (2H, t, J = 8.4 Hz) 8.35 (1H, d, J = 7.2) Hz), 8.82 (1H, s).
EI MS m / z = 321 [M] +

Method for producing compound 6

Preparation of Compound 6 A suspension of 2-fluoro-5-iodopyridine (112 mg, 0.5 mmol), Compound 2 (66.5 mg, 0.5 mmol) and cesium carbonate in DMF (4 mL) at 120 ° C. The mixture was stirred for 15 hours. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over magnesium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 6 (14.7 mg, 0.04) as a white-yellow solid. mmol, 8.8%) was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 6.83 (1H, d, J = 9.0 Hz), 7.01 (1H, d, J = 7.8 Hz), 7.54 (1H) , S), 7.82 (1H, s), 7.93 (1H, d, J = 7.8 Hz), 8.31 (1H, s), 8.43 (1H, d, J = 7. 8 Hz), 8.45 (1H, s) 9.82 (1H, s)
EI MS m / z = 321 [M] +

Method for producing compound 7

Step 1: Preparation of Compound 7-1 Dichloromethane of Compound 4-1 (617 mg, 2.78 mmol), (R)-(+) glycidol (184 μL, 2.78 mmol), triphenylphosphine (860 mg, 3.34 m mmol). 3 mL) Toluene solution of diethylazocarboxylate (1.5 mL, 3.34 mmol) was added dropwise to the suspension under ice-cooled stirring over 10 minutes, and the resulting mixture was ice-cooled for 1 hour and at room temperature 24. Stir for hours. The reaction mixture was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / n-hexane 7/3), the solvent was distilled off under reduced pressure, and compound 7-1 (509 mg) as a crude product was a white solid. Got

Step 2: Preparation of Compound _{7-2 7-1 (509mg), KHF 2} (214mg, 2.7mmol), Bu 4 N + H 2 F 3 - (551mg, 1.85mmol), dichlorobenzene (1 mL) The mixture was stirred at 120 ° C. for 7 hours. After completion of the reaction, the reaction mixture was made alkaline by adding an aqueous potassium carbonate solution under ice-cooling, and the reaction mixture was extracted with ethyl acetate. The organic layer was washed with water, dried with magnesium sulfate, filtered, the filtrate was evaporated under reduced pressure, and the obtained residue was purified by flash chromatography (eluting solvent: ethyl acetate / n-hexane 7/3). Compound 7-2 (142 mg, total of steps 1 and 2 17%) was obtained as a white solid.

Step 3: Preparation of Compound 7 In a suspension of Compound 7-2 (142 mg, 0.48 mmol), imidazo [1,2-a] pyridine-7-amine (92 mg, 0.7 mmol) in THF (5 mL). Pd ₂ (dba) ₃ (16 mg, 0.02 m mmol), Xant Phos (19 mg, 0.02 mmol), K ₃ PO ₄ (203 mg, 0.95 mmol) were added, nitrogen was bubbled for 5 minutes, and then at 80 ° C. for 18 hours. Stirred. The reaction mixture was allowed to cool to room temperature, saturated brine was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 7 (78 mg, 0.22 mmol, 46%) as a white-yellow solid. ) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 3.97-4.09 (3H, m), 4.43-4.57 (2H, m), 5.47 (1H, br), 6. 71 (1H, dd, J = 3.0, 7.2 Hz), 6.97 (1H, d, J = 1.8 Hz), 7.11 (1H, dd, J = 2.4, 9. 0 Hz), 7.27 (1H, J = 2.4 Hz), 7.30-7.32 (2H, m), 7.58 (1H, d, J = 1.8 Hz), 7.66 (1H, s), 7.73 (1H, d, J = 9.0 Hz), 8.33 (1H, d, J = 7.2 Hz), 8.69 (1H, s)

Method for producing compound 8

Preparation of Compound 8 In a suspension of 2,6-difluoropyridine (62 mg, 0.54 mmol), imidazo [1,2-a] pyridine-7-amine (108 mg, 0.81 mmol) in THF (8 mL). t-BuXPhosPdG3 (43.7 mg, 0.055 m mmol) and t-BuONa (0.48 mL, 0.96 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 8 (18.4 mg, 0.08 mmol) as a white solid. 15%) was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 6.49 (1H, dd, J = 3.0, 8.1 Hz), 6.78 (1H, d, J = 1.8, 7.8) Hz), 6.85 (1H, d, J = 1.8, 7.8 Hz), 7.37 (1H, s), 7.71 (1H, s), 7.74 (1H, dd, J) = 8.4, 16.8 Hz), 8.08 (1H, d, J = 1.2 Hz), 8.36 (1H, d, J = 6.6 Hz), 9.63 (1H, s) ).
EI MS m / z = 228 [M] +

Method for producing compound 9

Preparation of Compound 9 Suspension of 2-bromo-4-fluoropyridine (55 μL, 0.54 mmol), imidazo [1,2-a] pyridine-7-amine (108 mg, 0.81 mmol) in THF (8 mL) To the solution, t-BuXPhosPdG3 (43.7 mg, 0.055 m mmol) and t-BuONa (0.48 mL, 0.96 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 9 (45.6 mg, 0.20 mmol, 37) as a white solid. %) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.64 (1H, dd, J = 2.4, 6.9 Hz), 6.74-6.76 (1H, m), 6.86 ( 1H, d, J = 2.4, 6.9 Hz), 7.36 (1H, s), 7.70 (1H, s), 8.22 (1H, d, J = 1.8 Hz), 8.27 (1H, dd, J = 5.4, 6.9 Hz), 8.34 (1H, d, J = 7.2 Hz), 9.51 (1H, s).
EI MS m / z = 228 [M] +

Method for producing compound 10

Preparation of Compound 10 THF (8 mL) of 2-bromo-5-fluoropyridine (87.9 mg, 0.5 mmol), imidazo [1,2-a] pyridine-7-amine (108 mg, 0.81 mmol) To the suspension was added t-BuXPhosPdG3 (43.7 mg, 0.055 m mmol) t-BuONa (0.48 mL, 0.96 mmol), bubbling nitrogen for 5 minutes and then stirring at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 10 (24.5 mg, 0.1 mmol, 22) as a white solid. %) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.84 (1H, dd, J = 2.4, 6.9 Hz), 6.93 (1H, dd, J = 3.6, 9.3) Hz), 7.36 (1H, s), 7.59 (1H, td, J = 3.0, 8.7 Hz), 7.69 (1H, s), 8.22-8.23 (1H) , M), 8.33 (1H, d, J = 7.2 Hz), 9.49 (1H, s)
EI MS m / z = 228 [M] +

Method for producing compound 11

Step 1: Preparation of Compound 11-1 t-BuXPhosPdG3 in a suspension of 1,4-dibromobenzene (235.9 mg, 1 mmol), 3-fluoroazetidine hydrochloride (112 mg, 1 mmol) in THF (5 mL). (79.4 mg, 0.1 m mmol), t-BuONa (0.6 mL, 1.2 mmol) was added, nitrogen was bubbled for 5 minutes and then stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane 1/1), and the solvent was distilled off under reduced pressure to obtain a white solid compound 11-1 (46 mg, 0.2 mmol, 20%) was obtained.

Step 2: Preparation of Compound 11 Compound 11-1 (46 mg, 0.2 mmol), imidazo [1,2-a] pyridine-7-amine (40 mg, 0.3 mmol) in THF (5 mL) suspension. , T-BuXPhosPdG3 (15.9 mg, 0.1 m mmol) and t-BuONa (0.18 mL, 0.36 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 4/1), and the solvent was distilled off under reduced pressure to obtain compound 11 (8.6 mg, 0.03 mmol, 15) as a white solid. %) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 3.82-3.88 (2H, m), 4.10-4.16 (2H, m), 5.40-5.53 (1H, m) ), 6.53 (2H, d, J = 9.0 Hz), 6.62 (1H, d, J = 2.4 Hz), 6.89 (1H, dd, J = 1.8, 7. 5 Hz), 7.10 (2H, J = 9.0 Hz), 7.63 (1H, d, J = 2.4 Hz), 7.83 (1H, d, J = 1.8 Hz), 8.41 (1H, d, J = 7.2 Hz), 9.22 (1H, s).
EI MS m / z = 283 [M] +

Method for producing compound 12

Preparation of Compound 12 Suspension of 4-amino-2-fluoropyridine (31.3 mg, 0.28 mmol), 7-bromo-imidazole [1,2-a] pyridine (50 mg, 0.25 mmol) in THF (8 mL) liquid, Pd2 (dba) 3 (9.3 mg, 0.01mmmol), XantPhos (10.3 mg, 0.018mmmol), K 3 PO 4 (107.7mg, 0.51mmol) was added, at 80 ° C. The mixture was stirred for 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water and saturated brine, and extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 10/1), and the solvent was distilled off under reduced pressure to obtain compound 12 (15.5 mg, 0.067 mmol, 27) as a white solid. %) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.51 (1H, s), 6.76 (1H, dd, J = 1.8, 7.2 Hz), 6.90 (1H, d, J = 5.4 Hz), 7.21 (1H, d, J = 1.2 Hz), 7.43 (1H, s), 7.80 (1H, s), 7.90 (1H, d, s) J = 5.4 Hz), 8.45 (1H, d, J = 7.8 Hz), 9.36 (1H, s).
EI MS m / z = 228 [M] +

Method for producing compound 13

Preparation of Compound 13 Suspension of 5-amino-2-fluoropyridine (50 mg, 0.44 mmol), 7-bromo-imidazole [1,2-a] pyridine (80 mg, 0.41 mmol) in THF (4 mL) To the solution, Pd ₂ (dba) ₃ (14.8 mg, 0.016 m mmol), Xant Phos (16.4 mg, 0.028 m mmol), and K ₃ PO ₄ (181 mg, 0.85 mmol) were added, and 80 ° C. Was stirred for 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water and saturated brine, and extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 5/1), and the solvent was distilled off under reduced pressure to obtain compound 13 (15.9 mg, 0.069 mmol, 17) as a white solid. %) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.60 (1H, d, J = 6.6 Hz), 6.82 (1H, s), 7.11 (1H, d, J = 7. 8 Hz), 7.29 (1H, s), 7.65 (1H, s), 7.80 (1H, s), 8.01 (1H, s), 8.32 (1H, d, J = 7.8 Hz), 8.59 (1H, s).
EI MS m / z = 228 [M] +

Method for producing compound 14

_{Preparation of Compound 14 Pd 2} (Pd 2 (3 mL) suspension of 3-fluoroaniline (31 mg, 0.027 mmol), 7-bromo-imidazole [1,2-a] pyridine (50 mg, 0.25 mmol) in THF (4 mL). _{dba) 3 (9.3 mg, 0.01mmmol} ), XantPhos (10.3 mg, 0.018mmmol), K 3 PO 4 (113.1mg, 0.53mmol) and the mixture was stirred at 80 ° C. 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water and saturated brine, and extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 10/1), and the solvent was distilled off under reduced pressure to obtain compound 14 (10.3 mg, 0.045 mmol, 18) as a white solid. %) Was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.65 (1 H, d, J = 7.2 Hz), 6.90 (1 H, d, J = 11.4 Hz), 6.95-6 .98 (2H, m), 7.27-7.32 (2H, m), 7.68 (1H, s), 8.33 (1H, d, J = 7.8 Hz), 8.70 ( 1H, s).
EI MS m / z = 227 [M] +

Method for producing compound 15 (Example 1)

Step 1: Preparation of Compound 15-1 Dioxane of 5-bromo-4-fluoropyridin-2-amine (320 mg, 1.68 mmol), methylboronic acid (150 mg, 2.5 mmol): water (10: 1) In a (5 mL) suspension, [1,1-bis (diphenylphosphino) ferrocene] palladium (II) (137 mg, 0.17 m mmol), cesium carbonate (1364 mg, 4.18 mmol) was added at room temperature. In addition, the mixture was stirred at 115 ° C. for 23 hours in a nitrogen atmosphere. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water, saturated brine was added, and the mixture was extracted with ethyl acetate. The extract was dried over sodium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica gel, elution solvent: chloroform / methanol 20/1), and the solvent was distilled off under reduced pressure to obtain a yellow solid compound 15-1 (182 mg, 1.44 mmol, 86). %) Was obtained.
EI MS m / z = 126 [M] +

Step 2: Preparation of Compound 15 THF (4 mL) suspension of Compound 15-1 (160 mg, 1.27 mmol), 7-bromo-imidazole [1,2-a] pyridine (250 mg, 1.27 mmol). To, t-BuXPhosPdG3 (100 mg, 0.127 m mmol) and a THF solution of t-BuONa (1.27 mL, 2.54 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 18 hours. .. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water and saturated brine, and extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (NH2 silica gel, elution solvent: chloroform / methanol 20/1), and the solvent was distilled off under reduced pressure to obtain compound 15 (14 mg, 0.058 mmol, 5) as a white solid. %) Was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 2.12 (3H, s), 6.62 (1H, d, J = 11.4Hz), 6.81 (1H, d, J = 7.2) Hz), 7.33 (1H, s), 7.67 (1H, s), 8.14 (1H, d, J = 10.8 Hz) 8.18 (1H, s), 8.31 (1H) , D, J = 7.8 Hz), 9.35 (1H, s).
EI MS m / z = 242 [M] +

Method for producing compound 15 (Example 2)

Preparation of Compound 15 t-butanol of 2-bromo-4-fluoro-5-methylpyridine (190 mg, 1 mmol), imidazole [1,2-a] pyridine-7-amine (214 mg, 1.6 mmol) To the (10 mL) suspension, t-BuXPhosPdG3 (70 mg, 0.1 m mmol) and t-BuONa (192 mg, 2 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 2 hours. The reaction mixture was allowed to cool to room temperature, and the solvent was evaporated under reduced pressure. Ethyl acetate was added, the mixture was washed with water and saturated brine, and extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 4/1), and the solvent was distilled off under reduced pressure. The crude product was dissolved in chloroform / methanol 9/1 (50 mL), Quadrasil ^TM MP (2.5 g) was added, and the mixture was stirred and then filtered. The filtrate was washed with chloroform / methanol and purified again by flash chromatography (silica gel, elution solvent: chloroform / methanol 4/1). The solvent of the recovered fraction was distilled off under reduced pressure and then repurified by flash chromatography (ODS, elution solvent: methanol / 10 mM ammonium acetate, gradient), the solvent was distilled off under reduced pressure, and compound 15 (16. 4 mg, 0.067 mmol, 7%) was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 2.17 (3H, s), 6.62 (1H, d, J = 12.0 Hz), 6.82 (1H, d, J = 1. 8, 7.5 Hz), 7.34 (1H, s), 7.68 (1H, s), 8.14 (1H, d, J = 11.4 Hz) 8.18 (1H, d, J) = 1.8 Hz), 8.32 (1H, d, J = 7.8 Hz), 9.37 (1H, s).
EI MS m / z = 242 [M] +

Method for producing compound 16

Step 1: Preparation of Compound 16-1 1,2- of 2-amino-5-bromopyridine (420 mg, 2.42 mmol), 2-fluoropyridine-4-boronic acid (362 mg, 2.42 mmol) Dimethoxyethane: Tetrakis (triphenylphosphine) palladium (0) (279 mg, 0.24 m mmol), potassium carbonate (1003 mg, 7.26 mmol) in a suspension of water (50: 1) (10.2 mL). ) Was added, and the mixture was stirred at 80 ° C. for 18 hours under an argon atmosphere. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over sodium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane 9/1), the solvent was distilled off under reduced pressure, and compound 16-1 (453 mg, 0.239) as a white solid was distilled off. mmol, 99%) was obtained.
EI MS m / z = 189 [M] +

Step 2: Preparation of Compound 16 Compound 16-1 (450 mg, 2.3 mmol), 7-bromo-imidazo [1,2-a] pyridine (469 mg, 2.3 mmol) in THF (10 mL). Add XantPhos (96 mg, 0.17 m mmol), tris (dibenzylideneacetone) dipalladium (0) (80 mg, 0.087 mmol), and tripotassium phosphate (1060 mg, 4.99 mmol) to the turbid solution. In addition, argon was bubbled for 5 minutes and then stirred at 80 ° C. for 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, and the filtrate was washed with saturated brine and water, and then extracted with ethyl acetate. The extract was dried over sodium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica, elution solvent: chloroform / methanol, gradient 12 → 19%), the solvent was distilled off under reduced pressure, and then chromatography (silicaine NH2, elution solvent: chloroform / methanol) was performed. , Gradient 0 → 6%), and the solvent was evaporated under reduced pressure to give compound 16 (30 mg, 0.108 mmol, 4.5%) as a yellow solid.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.92 (1 H, dd, J = 1.8, 7.5 Hz), 6.99 (1 H, d, J = 9.0 Hz), 7 .37 (1H, s), 7.53 (1H, s), 7.70-7.71 (2H, m), 8.13 (1H, dd, J = 3.0, 8.7 Hz), 8.24 (1H, d, J = 5.4 Hz), 8.34 (1H, d, J = 1.2 Hz), 8.36 (1H, d, J = 7.2 Hz), 8. 83 (1H, d, J = 2.4 Hz), 9.68 (1H, s)
EI MS m / z = 305 [M] +

Method for producing compound 17

Step 1: Preparation of Compound 17-1 1,2- of 2-amino-5-bromopyridine (230 mg, 1.33 mmol), 2-fluoropyridine-5-boronic acid (362 mg, 1.45 mmol) Dimethoxyethane: in a suspension of water (50: 1) (30.6 mL), tetrakis (triphenylphosphine) palladium (0) (153 mg, 0.115 m mmol), potassium carbonate (551 mg, 3.45 mmol). ) Was added, and the mixture was stirred at 80 ° C. for 18 hours under an argon atmosphere. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane 9/1), and the solvent was distilled off under reduced pressure to obtain compound 17-1 (136.5 mg, 0) as a white solid. .722 mmol, 54%) was obtained.
EI MS m / z = 189 [M] +

Step 2: Preparation of Compound 17 Compound 17-1 (100 mg, 0.53 mmol), 7-bromoimidazo [1,2-a] pyridine (104 mg, 0.53 mmol) in THF (10 mL). In the turbid solution, XantPhos (22 mg, 0.038 m mmol), tris (dibenzylideneacetone) dipalladium (0) (18.7 mg, 0.02 mmol), tripotassium phosphate (242 mg, 1.14 mmol). ) Was added, and the nitrogen was bubbled for 5 minutes and then stirred at 80 ° C. for 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, and the filtrate was washed with saturated brine and water, and then extracted with ethyl acetate. The extract was dried over sodium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica gel, elution solvent: chloroform / methanol, 9/1), and the solvent was distilled off under reduced pressure to obtain compound 17 (39 mg, 0.128 mmol, 24) as a yellow solid. %) Was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 6.90 (1H, dd, J = 2.4, 7.5 Hz), 6.98 (1H, d, J = 8.4 Hz), 7 .26 (1H, dd, J = 3.0, 9.0 Hz), 7.35 (1H, s), 7.69 (1H, s), 7.99 (1H, dd, J = 3.0) , 8.4 Hz), 8.27 (1H, td, J = 3.0, 8.1 Hz), 8.33 (1H, d, J = 1.8 Hz), 8.34 (1H, d) , J = 7.8 Hz), 8.54 (1H, d, J = 2.4 Hz), 8.64 (1H, d, J = 2.4 Hz), 9.54 (1H, s)
EI MS m / z = 305 [M] +

Method for producing compound 18

Step 1: Preparation of Compound 18-1 1,2- of 2-amino-5-bromopyridine (200 mg, 1.15 mmol), 2-fluoropyridine-3-boronic acid (189 mg, 1.26 mmol) Dimethoxyethane: Tetrakis (triphenylphosphine) palladium (0) (153 mg, 0.115 m mmol), potassium carbonate (476 mg, 3.45 mmol) in a suspension of water (50: 1) (10.2 mL). ) Was added, and the mixture was stirred at 80 ° C. for 21 hours under an argon atmosphere. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over sodium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane 9/1), the solvent was distilled off under reduced pressure, and compound 18-1 (80 mg, 0.42) as a white solid was distilled off. mmol, 38%) was obtained.
EI MS m / z = 189 [M] +

Step 2: Preparation of Compound 18 Compound 18-1 (70 mg, 0.37 mmol), 7-bromo-imidazo [1,2-a] pyridine (73 mg, 0.37 mmol) in THF (10 mL). Add XantPhos (15 mg, 0.027 m mmol), tris (dibenzylideneacetone) dipalladium (0) (13 mg, 0.0138 mmol), and tripotassium phosphate (168 mg, 0.79 mmol) to the turbid solution. In addition, the nitrogen was bubbled for 5 minutes and then stirred at 80 ° C. for 17 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, and the filtrate was washed with saturated brine and water, and then extracted with ethyl acetate. The extract was dried over sodium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica, elution solvent: chloroform / methanol, gradient 13 → 20%), the solvent was distilled off under reduced pressure, and then chromatography (silicaine NH2, elution solvent: chloroform / methanol) was performed. , Gradient 0 → 4%), and the solvent was evaporated under reduced pressure to give compound 18 (23 mg, 0.076 mmol, 20%) as a yellow solid.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.92 (1 H, dd, J = 2.4, 7.5 Hz), 7.00 (1 H, d, J = 9.0 Hz), 7 .35 (1H, d, J = 1.2 Hz), 7.43-7.46 (1H, m), 7.70 (1H, s), 7.87-7.89 (1H, m), 8.13-8.16 (1H, m), 8.19 (1H, d, J = 4.8 Hz), 8.51 (1H, s), 9.58 (1H, s)
EI MS m / z = 305 [M] +

Method for producing compound 19

Step 1: Preparation of Compound 19-1 1,2- of 2-amino-4-bromopyridine (200 mg, 1.15 mmol), 6-fluoropyridine-4-boronic acid (189 mg, 1.26 mmol) Dimethoxyethane: Tetrakis (triphenylphosphine) palladium (0) (153 mg, 0.115 m mmol), potassium carbonate (476 mg, 3.45 mmol) in a suspension of water (50: 1) (10.2 mL). ) Was added, and the mixture was stirred at 80 ° C. for 24 hours under an argon atmosphere. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. After washing with water, the extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane 9/1), and the solvent was distilled off under reduced pressure to obtain compound 19-1 (231 mg, 0.722) as a white solid. mmol, quant) was obtained.
EI MS m / z = 189 [M] +

Step 2: Preparation of Compound 19 Compound 19-1 (52.8 mg, 0.28 mmol), 7-bromo-imidazole [1,2-a] pyridine (50 mg, 0.25 mmol) in THF (4 mL) suspension. To the turbid solution, t-BuXPhosPdG3 (20.2 mg, 0.025 m mmol) and t-BuONa (48.8 mg, 0.51 mmol) were added, nitrogen was bubbled for 5 minutes, and then the mixture was stirred at 50 ° C. for 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water, saturated brine was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica gel, elution solvent: chloroform / methanol 5/1), the solvent was distilled off under reduced pressure, and compound 19 (5.1 mg, 0.017 mmol, 6. 6%) was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 6.95 (1H, dd, J = 1.8, 6.3 Hz), 7.23 (1H, s), 7.26 (1H, dd, J = 1.8, 4.5 Hz), 7.40 (1H, s), 7.53 (1H, s), 7.67 (1H, d, J = 6.0 Hz), 7.73 ( 1H, s), 8.33 (1H, s), 8.37 (2H, d, J = 5.4 Hz), 8.40 (1H, d, J = 5.4 Hz), 9.64 ( 1H, s)
EI MS m / z = 305 [M] +

Method for producing compound 20

Step 1: Preparation of Compound 20-1 Dioxane of 2-amino-4-bromopyridine (200 mg, 1.16 mmol), 6-fluoropyridine-3-boronic acid (345 mg, 2.45 mmol): water (10: 1) In a suspension of (8.8 mL), [1,1-bis (diphenylphosphino) ferrocene] palladium (II) (85.1 mg, 0.12 m mmol), cesium carbonate (947.3 mg, 2. 91 mmol) was added at room temperature, and the mixture was stirred at 115 ° C. for 24 hours under a nitrogen atmosphere. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water, saturated brine was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica gel, elution solvent: ethyl acetate / hexane 8/1), and the solvent was distilled off under reduced pressure to obtain a yellow solid compound 20-1 (166.7 mg, 0.88 mmol). , 75.2%).
EI MS m / z = 189 [M] +

Step 2: Preparation of Compound 20 Suspension of THF (4 mL) of Compound 20-1 (52.8 mg, 0.28 mmol), 7-bromo-imidazole [1,2-a] pyridine (50 mg, 0.25 mmol). To the turbid solution, t-BuXPhosPdG3 (20.2 mg, 0.025 m mmol) and t-BuONa (48.8 mg, 0.51 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 24 hours. .. The reaction mixture was allowed to cool to room temperature, filtered through Celite, the filtrate was washed with water, saturated brine was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (silica gel, elution solvent: chloroform / methanol 5/1), and the solvent was distilled off under reduced pressure to obtain compound 20 (11.2 mg, 0.036 mmol) as a yellow solid. 14.5%) was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 6.93 (1H, d, J = 7.8 Hz), 7.14 (1H, s), 7.19 (1H, d, J = 5. 4 Hz), 7.34 (1H, d, J = 9.0 Hz), 7.38 (1H, s), 7.71 (1H, s), 8.29-8.36 (4H, m) , 8.59 (1H, s), 9.55 (1H, s)
EI MS m / z = 305 [M] +

Method for producing compound 21

Step 1: Preparation of Compound 21-1 In a suspension of 2-chloro-5-hydroxypyridine (148 mg, 1.14 mmol) in N, N-dimethylformamide (DMF) (8 mL), potassium carbonate (236. 9 mg (1.71 m mmol) was added, and after stirring for 10 minutes, 2-fluoroethyl-4-methylbenzenesulfonate (261.6 mg, 1.20 mmol) dissolved in 1 mL DMF was added, and the temperature was 70 ° C. Was stirred for 2 hours. The reaction mixture was allowed to cool to room temperature, water was added, the mixture was extracted with ethyl acetate, washed with saturated brine, dried over magnesium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: hexane / ethyl acetate, 2/1), and the solvent was distilled off under reduced pressure to obtain compound 21-1 (93.5%) as a white solid. Got
EI MS m / z = 175 [M] +

Step 2: Preparation of Compound 21 22-1 (37.5 mg, 0.28 mmol), imidazole [1,2-a] pyridine-7-amine (213 mg, 1.6 mmol) in THF (4 mL) To the suspension, t-BuXPhosPdG3 (22.4 mg, 0.028 m mmol) and t-BuONa (0.3 mL, 0.59 mmol) were added, nitrogen was bubbled for 5 minutes, and then at 50 ° C. for 24 hours. Stirred. The reaction mixture was allowed to cool to room temperature, diluted with ethyl acetate, and filtered through Celite. Saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol, gradient 7 → 15%), and the solvent was distilled off under reduced pressure to obtain compound 21 (31.8%) as a white solid. Obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 4.24 (2H, dd, J = 3.6, 30.0 Hz), 4.71 (2H, dd, J = 3.6, 30.0) Hz), 6.89-6.92 (2H, m), 7.39-7.43 (2H, m), 7.72 (1H, s), 8.02 (1H, s), 8.26 (1H, s), 8.34 (1H, s), 9.43 (1H, s)
EI MS m / z = 272 [M] +

Method for producing compound 22

Step 1: Preparation of Compound 22-1 Copper iodide (4 mL) in dimethyl sulfoxide (4 mL) suspension of 2,6-dibromonaphthalene (283 mg, 1 mmol), 3-fluoroazetidine hydrochloride (112 mg, 1 mmol). 19 mg, 0.1 m mmol), [(2,6-dimethylphenyl) amino] (oxo) acetic acid (38.6 mg, 0.2 mmol) was added, nitrogen was bubbled for 5 minutes, and then stirred at 90 ° C. for 18 hours. did. The reaction mixture was allowed to cool to room temperature, water was added, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane 3/7), and the solvent was distilled off under reduced pressure to obtain compound 22-1 (124 mg, 0.44) as a white solid. mmol, 20%) was obtained.

Step 2: Preparation of Compound 22 Suspension of Compound 22-1 (124 mg, 0.44 mmol), imidazo [1,2-a] pyridine-7-amine (89 mg, 0.66 mmol) in THF (8 mL). To the turbid solution, t-BuXPhosPdG3 (35 mg, 0.04 m mmol) and t-BuONa solution (0.78 mL, 0.39 mmol) were added, nitrogen was bubbled for 5 minutes, and the mixture was stirred at 50 ° C. for 18 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol 9/1), and the solvent was distilled off under reduced pressure to obtain compound 22 (65.5 mg, 0.19 mmol) as a white solid. , 43%).
1H NMR (600 MHz, DMSO-d ₆ ) δ 3.89-3.95 (2H, m), 4.18-4.24 (2H, m), 6.65 (1H, dd, J = 1. 8, 7.8 Hz), 6.71 (1H, s), 6.82 (1H, dd, J = 2.4, 9.0 Hz), 6.92 (1H, s), 7.25 ( 1H, dd, J = 1.8, 9.0 Hz), 7.28 (1H, s), 7.51 (1H, s), 7.62-7.68 (3H, m), 8.29 (1H, d, J = 7.2 Hz), 8.51 (1H, s)
EI MS m / z = 332 [M] +

Method for producing compound 23

Step 1: Preparation of Compound 23-1 4-nitro-2-aminopyridine (77.7 mg, 0.56 mmol), 7-bromo-imidazo [1,2-a] pyridine (100 mg, 0.51 mmol) ) To a suspension of THF (4 mL) was added t-BuXPhosPdG3 (40.3 mg, 0.051 m mmol) and t-BuONa (97.6 mg, 1.02 mmol), and nitrogen was bubbled for 5 minutes. Later, it was stirred at 50 ° C. for 24 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, and eluted with a chloroform solution containing 10% methanol. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by chromatography (NH2 silica gel, elution solvent: chloroform / methanol 50/1), the solvent was distilled off under reduced pressure, and the yellow solid compound 23-1 (9.2 mg, 0. 036 mmol, 7.07%) was obtained.
EI MS m / z = 255 [M] +

Step 2: Preparation of Compound 23 Triethylamine (0.033 mL, 0.23 m mmol), N, N in a dichloromethane (3 mL) suspension of Compound 21-1 (6 mg, 0.023 mmol) at 0 ° C. -Dimethyl-4-aminopyridine (4.3 mg, 0.0012 mmol) was added, and the mixture was stirred for 10 minutes, then di-tert-butyl dicarbonate (51.3 mg, 0.23 mmol) was added, and the mixture was added at room temperature for 24 hours. Stirred. Water was added to the reaction mixture, and the mixture was extracted with chloroform. The extract was washed with water, washed with saturated brine, dried over magnesium sulfate, filtered, and the filtrate was evaporated under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: ethyl acetate / hexane, 7/1), the solvent was distilled off under reduced pressure, and the yellow solid compound 23 (4.1 mg, 0. 012 mmol, 55.1%) was obtained.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ 1.40 (9H, s), 6.83 (1H, d, J = 7.8 Hz), 7.41 (1H, s), 7.56 (1H, s), 7.88 (1H, d, J = 5.4 Hz), 7.93 (1H, s), 8.49 (1H, s), 8.52 (1H, d, J = 7.2 Hz), 8.56 (1H, d, J = 5.4 Hz)
EI MS m / z = 355 [M] +

Method for producing compound 24

Step 1: Preparation of Compound 24-1-1 2-bromo-5-methyl-4-nitropyridine (217 mg, 1 mmol), imidazo [1,2-a] pyridine-7-amine (213 mg, 1.6 mmol) To a suspension of THF (10 mL), t-BuXPhosPdG3 (79.4 mg, 0.1 m mmol) and t-BuONa (1 mL, 2 mmol) were added, nitrogen was bubbled for 5 minutes, and then at 50 ° C. The mixture was stirred for 20 hours. The reaction mixture was allowed to cool to room temperature, filtered through Celite, saturated brine was added to the filtrate, and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel, elution solvent: chloroform / methanol, gradient 7 → 15%), and the solvent was distilled off under reduced pressure to obtain compound 24-1 (67.7 mg) as an orange solid. , 0.25 mmol, 25%).

Step 2: Preparation of Compound 24 Triethylamine (65 mg, 0.25 mmol), di-tert-butyl dicarbonate (213 mg, 1.6 mmol) in a dichloromethane (5 mL) suspension of compound 24-1 (65 mg, 0.25 mmol). 0.278 mL, 2.0 m mmol) and N, N-dimethyl-4-aminopyridine (4.4 mg, 0.036 mmol) were added, and the mixture was stirred at room temperature for 18 hours. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The extract was dried over sodium sulfate, filtered, and the filtrate was distilled off under reduced pressure. The obtained residue was purified by flash chromatography (silica gel NH ₂ , elution solvent: ethyl acetate / hexane, gradient 73/27 → 94/6%), and the solvent was evaporated under reduced pressure to produce a yellow solid compound 24. (20 mg, 0.05 mmol, 20%) was obtained.
^{1 1} H NMR (600 MHz, DMSO-d ₆ ) δ 1.39 (9H, s), 2.41 (3H, s), 6.80 (1H, dd, J = 2.4, 6.9 Hz) , 7.35 (1H, s), 7.54 (1H, s), 7.91 (1H, s), 8.23 (1H, s), 8.45 (1H, s) 8.50 (1H) , D, J = 7.2 Hz).
EI MS m / z = 369 [M] +

Next, a synthesis example of the labeled compound of the present invention will be shown, but the present invention is not limited thereto.
¹⁸ F in by irradiating labeled compound 9 of the manufacturing cyclotron HM12 (Sumitomo Heavy Industries) ^[18 O] was 12eV proton beam isotopic purity of 98% or more of the acceleration in H2 O ¹⁸ F ^- to produce the. Subsequently, the solution was passed through an anion exchange resin (MAX cartridge) ^{to capture 18} F ⁻ on the resin, and 20 mM K222. It was eluted with KHCO3-methanol solution. Similarly, ^{50 μL (392 MBq) of 18} F ^- containing KHCO ₃ -methanol solution was placed in a brown vial, and He gas was sprayed at 85 ° C. to dry it. A DMSO solution of compound 21 (3 mg / mL, 50 μL) was added to the reaction vial and reacted at 150 ° C. for 10 minutes. The temperature was returned to room temperature, water (200 μL) was added, and the mixture was reacted at 100 ° C. for 10 minutes. After returning to room temperature, semi-prepared high performance liquid chromatography (column: Inertsil Sustain C18 (7.6 × 150 mm), mobile phase: acetonitrile / 20 mM phosphate buffer, pH 7.5 = 70/30, flow velocity: 2.0 mL Purification was carried out by applying (/ min, wavelength: 254 nm). Radioactive peaks with a retention time of 9-10 minutes were collected, diluted with 15 mL of distilled water and passed through a Sep-Pak Plus Light tC18 cartridge. It was washed with 10 mL of distilled water and eluted with 0.5 mL of ethanol. Compound 9 labeled ^{with 18} F with a radiochemical purity of 99% was obtained.

Similar to the preparation of compound 15 labeled with ^{18 F, 50 μL (743 MBq) of 18} F ^- containing KHCO ₃ -methanol solution was placed in a brown vial, sprayed with He gas at 85 ° C., and dried. A DMSO solution of compound 21 (3 mg / mL, 50 μL) was added to the reaction vial and reacted at 150 ° C. for 10 minutes, then returned to room temperature, water (200 μL) was added and reacted at 100 ° C. for 10 minutes. After returning to room temperature, semi-prepared high performance liquid chromatography (column: Inertsil Sustain C18 (7.6 × 150 mm), mobile phase: acetonitrile / 20 mM phosphate buffer, pH 7.5 = 70/30, flow velocity: 3.0 mL Purification was carried out by applying (/ min, wavelength: 254 nm). Radioactive peaks with a retention time of 9-10 minutes were collected, diluted with 15 mL of distilled water and passed through a Sep-Pak Plus Light tC18 cartridge. It was washed with 10 mL of distilled water and eluted with 0.5 mL of ethanol. Compound 15 labeled ^{with 18} F with a radiochemical purity of 98% was obtained.

Further, a test example relating to the performance of the compound of the present invention will be described.

Competitive binding test for tau, amyloid, monoamine oxidase (hereinafter also referred to as MAO) -B, MAO-A Alzheimer's disease (hereinafter also referred to as AD) The binding affinity for tau contained in the brain is Alzheimer's disease brain (hereinafter also referred to as AD). Braak Stage VI) and a labeled ligand ^[3 H] MK-6240, binding affinity for amyloid β to be included in the AD brain with Alzheimer's disease brain (Braak stage VI) a labeled ligand ^[18 F] Florbetaben, for MAO-B binding affinity recombinant MAO-B (Sigma Aldirch, M7441 , St. Louis, MO) and labeled ligand ^[3 H] THK-5351, the binding affinity for MAO-a recombinant MAO-a (Sigma Aldirch, Competitive binding tests were performed using M7316, St. Louis, MO) and a labeled ligand [ ^{18 F] Fluoroethyl oxidase.} To the reaction solution, a labeled ligand, a test compound, AD brain or MAO protein, and 200 μL were added and reacted at room temperature. Transfer the reaction solution to a MultiScreen HTS 96-well 0.65 μm filtration plate (Millipore, Billerica, MA), perform B / F separation with a MultiScreen HTS Vacum Manifold, wash with Dulvecco's SA PBS, 0.1% Was done. ^[3 H] compound of binding of 2mL against filter Scintillation fluid (Emulssifer-Safe; Perkin Elemer, Boston, MA) After incubation, the beta counter (LS6500 liquid scintillation counter, Beckman Counter , Brea, CA) was used Was measured. ¹⁸ binding of F-labeled compound was determined using a gamma counter (AccFLEX γ7000, ALOKA). IC ₅₀ values were calculated using Graph Pad Prism Version 7 (GraphPad SoftWare , San Diego, CA).
As the comparative compounds in this test, THK-5351, AV-1451 and JNJ-067, which are known as compounds having binding property to tau, were used. THK-5351 and AV-1451 were prepared based on the related contents among the patent documents and non-patent documents listed as prior art documents. As JNJ-067, the one purchased from ASTA TECH was used.

(result)
Tau of the compound of the present invention, amyloid beta, _{IC 50} values for MAO-B are shown in Table 1. _{The unit of IC 50} in Table 1 is nM. As is well known, means that the high binding affinity lower number of IC ₅₀ of less, which means that low binding affinity as numerical an IC ₅₀ is high. Although JNJ-067 of the comparative compound shows a high binding affinity for tau, _{IC 50} value indicates a 58.9nM against MAO-B. On the other hand, all of the above compounds of the present invention have remarkably high binding properties to tau as compared with amyloid β and MAO-B. That is, it has excellent binding selectivity for tau.

また、本発明化合物はＭＡＯ−Ａに対しても結合性を示さなかった（表２、ＩＣ_５０の単位はｎＭ）。Ｆｌｕｏｒｏｅｔｈｙｌ ｈａｒｍｉｎｅは比較化合物の１つであり、ＭＡＯ−Ａを計測するＰＥＴトレーサーとして広く知られている。

In addition, the compound of the present invention did not show binding property to MAO-A (Table 2, _{the unit of IC 50} is nM). Fluoroethyl harmine is one of the comparative compounds and is widely known as a PET tracer for measuring MAO-A.

Calculation of Contrast Ratio in In vitro Autoradiography and Autoradiography Images for Human Autoradiograph Brain 12 μm sliced frozen sections of Alzheimer's disease autoradiography brain (Braak stage VI) were dried at room temperature and then combined with PBS. Wetting was performed for 30 minutes, and Pre-incubation was performed with PBS and 1% BSA for 30 minutes. ¹⁸ F PBS of a labeled compound, 1% BSA solution (370 kBq / mL) was added dropwise to sections were reacted for 30 minutes at room temperature. In order to investigate the possibility of off-target binding to MAO-A and MAO-B, the same study was conducted in the presence of Clorigline (MAO-A inhibitor) and Rasagiline (MAO-B inhibitor) (1 μM). The sections were then soaked twice in PBS for 5 minutes and then in PBS for 5 minutes and washed. After the sections were dried at room temperature, they were exposed to an imaging plate (GE Healthcare, BAS-MS2025), and images (spatial resolution 25 μm × 25 μm) were obtained with an FLA-9500 imaging analyzer (GE Healthcare). Adjacent sections were immunostained with MAO-B (Sigma Aldrich), AT8 tau (Innogenetics), and 6F / 3D β-amyloid (DAKO) antibodies and compared with the tracer binding distribution. This test was ^{also carried out for [18} F] JNJ-067, [ ¹⁸ F] PI-2620, [ ¹⁸ F] AV-1451, and [ ¹⁸ F] THK-5351 as comparative compounds. Each comparative compound was prepared based on the related documents among the patent documents and the non-patent documents listed as prior art documents. In addition, the contrast ratio of various tracers in the temporal lobe brain section of Alzheimer's disease is measured by measuring the radioactivity count of gray matter and white matter using ImageQuant TL (GE Healthcare), and the gray matter value is divided by the white matter value. It was calculated by.

(result)
The results of autoradiography are shown in FIGS. 1, 2 and 3.
¹⁸ The present invention specific binding of compounds 9 and 15 were labeled with F is, Clorygline (MAO-A inhibitors), since it does not change with rasagiline (MAO-B inhibitor), selectively coupled to tau ( Figure 1).
To ^[3 H] of THK-5351 is also coupled to the basal ganglia (putamen) containing ^{MAO-B, 18} F-labeled compounds ^{9, 18} F-labeled compound 15 cerebral cortex (Shimakai) only It showed a laminar-like binding pattern and was consistent with the pattern of immunostaining of tau (Fig. 2).
^{The results of autoradiography of 18} F-labeled compound 9, ¹⁸ F-labeled compound 15, various tau PET tracers, and amyloid PET tracer are shown in FIG. The result of calculating the contrast ratio between gray matter and white matter is shown in FIG. The second generation tau tracers [ ¹⁸ F] PI-2620, [ ¹⁸ F] JNJ-067, and the first generation tau PET tracers [ ¹⁸ F] AV-1451, [ ¹⁸ F] THK-5351 while accumulation in white matter is observed, and visualization of tau in ^{[18 F]} labeled compounds 9, ^{18 F-labeled} compound 15 contrast accumulation in white matter with excellent almost without. The ratio of the accumulation of gray matter and white matter, known tau PET tracers while a less than 3 was ^{18 F-labeled} compounds 9, ^{18 F-labeled} compound 15 in 20 or more. That is, it is considered that the compound of the present invention can visualize tau lesions with higher sensitivity than the existing tau PET tracer. In addition, it showed an accumulation distribution different from ^{that of [18} F] Florbetaben and [ ³ H] PiB, which are amyloid PET tracers.

In normal mice, the present compounds 9 and 15 Pharmacokinetics evaluation labeled with ^{18 F
Physiological saline (740 kBq) containing compounds 9 and 15 of the present invention labeled with 18} F was administered to male ICR mice (6 weeks old) by tail intravenous injection, and after a predetermined time had elapsed, after a predetermined time had passed. At multiple different time points, cervical dislocation was performed under isoflurane anesthesia, each organ including the brain was removed, and the weight and radioactivity of each organ were measured with a gamma counter (AccuFLEX γ7000, manufactured by ALOKA). The evaluation of radioactivity accumulation was based on the ratio of radioactivity per unit weight of tissue to total administered radioactivity (% infusion dose / tissue g;% ID / g). It was carried out with 4 animals in a group. For comparison, [ ¹⁸ F] THK-5351 and [ ¹⁸ F] AV-1451 were also carried out in the same manner.

(result)
Table 3 shows the profile of pharmacokinetic properties in mice. ^The compound 15 of the present invention labeled with 18 F was transferred to the brain immediately after administration (the amount taken up in the brain 2 minutes after administration was 4% ID / g or more), and then was immediately washed out. Compared with the dynamics of THK-5351 and AV-1451, which are the first generation tau tracers, the brain uptake ratio of 2 minutes / 60 minutes is excellent. Therefore, it is considered possible to detect tau with high sensitivity in vivo.

Since the compound of the present invention has high specificity and selectivity for tau protein, has central migration, and can visualize tau with good sensitivity, for example, early detection of conformational diseases such as Alzheimer's disease, It is useful for diagnosis, treatment and prevention, and is also useful for the development of diagnostic agents and therapeutic agents for these diseases, preventive agents, and research on these diseases.

Claims (22)

General formula (I-1)

General formula (I-2)

General formula (I-3)

Or general formula (I-4)

[In each general formula,
X is carbon (CH) or nitrogen (N),
R ¹ , R ² and R ³ are independently substituted with hydrogen, halogen and lower alkyl groups, respectively (the alkyl groups are independently substituted with one or more substituents selected from halogen and hydroxy groups, respectively. (May be), -O-lower alkyl group (the alkyl group may be independently substituted with one or more substituents selected from halogen and hydroxy groups) or

The ring Y represents an azetidine ring, a benzene ring or a pyridine ring.
R ⁴ is halogen, lower alkyl group (the alkyl group each independently may be substituted with one or more substituents selected from halogen and hydroxy group), or -O- lower alkyl group (The alkyl groups may be independently substituted with one or more substituents selected from halogen and hydroxy groups).
In R ^{1 to} R ⁴ , at least one of them is a halogen, a lower alkyl group (the alkyl group is substituted with at least one halogen), or an -O- lower alkyl group (the alkyl group is at least one). It is replaced with halogen)]
A compound represented by (1) or a pharmaceutically acceptable salt or solvate thereof. ^{The compound according to claim 1, wherein R 3} is hydrogen, which is represented by the general formula (I-1), or a pharmaceutically acceptable salt or solvate thereof. The compound according to claim 1, or a pharmaceutically acceptable salt or solvate thereof, which is represented by the general formula (I-4) and in which R ² and R ^{3 are hydrogen.} The compound according to any one of claims 1 to 3, or a pharmaceutically acceptable salt or solvate thereof, which comprises at least one F or I as a halogen.

The compound according to claim 1 or a pharmaceutically acceptable salt or solvate thereof. The compound according to any one of claims 1 to 5, labeled with a radionuclide, or a pharmaceutically acceptable salt or solvate thereof. Radionuclides are ³ H, ¹¹ C, ¹⁴ C, ¹⁸ F, ¹²³ I, ¹²⁴ I
Or ¹²⁵ I, the compound of claim 6 or a pharmaceutically acceptable salt or solvate thereof. The compound according to claim 7, wherein the radionuclide is ¹⁸ F, or a pharmaceutically acceptable salt or solvate thereof. The compound according to claim 7, wherein the radionuclide is ³ H or ¹⁴ C, or a pharmaceutically acceptable salt or solvate thereof. A pharmaceutical composition containing the compound according to any one of claims 1 to 9 or a pharmaceutically acceptable salt or solvate thereof. A composition for diagnosing conformational diseases, which comprises the compound according to any one of claims 1 to 9 or a pharmaceutically acceptable salt or solvate thereof. A pharmaceutical composition for treating and / or preventing conformational diseases, which comprises the compound according to any one of claims 1 to 9 or a pharmaceutically acceptable salt or solvate thereof. A kit for synthesizing or producing the compound according to any one of claims 6 to 9 or a pharmaceutically acceptable salt or solvate thereof. A composition or kit for detecting or staining a β-sheet structural protein, which comprises the compound according to any one of claims 1 to 9 or a pharmaceutically acceptable salt or solvate thereof as an essential component. .. The kit according to claim 13, which is used for nuclear medicine diagnostic imaging. A method for diagnosing a conformational disease in a subject, which comprises administering the compound according to any one of claims 6 to 9 or a pharmaceutically acceptable salt or solvate thereof to the subject. Treatment and / or prevention of conformational disease in a subject, characterized in that the compound according to any one of claims 1 to 9 or a pharmaceutically acceptable salt or solvate thereof is administered to the subject. Method. Detecting or detecting a β-sheet structural protein in a sample, characterized in that the sample is stained with the compound according to any one of claims 1 to 9 or a pharmaceutically acceptable salt or solvate thereof. How to dye.

Or

(In Chemical formulas 7 to 10, X, R ¹ , R ² , and R ³ are as defined in claim 1, and Z represents a halogen).

The method for producing a compound according to claim 1, which comprises a step of reacting the compound of the above.

Or

With the compound of (X, R ¹ , R ² , R ³ are as defined in claim 1 in Chemical formulas 12 to 15)

(Z represents halogen in Chemical formula 16)
The method for producing a compound according to claim 1, which comprises a step of reacting the compound of the above. General formula (II-1)

General formula (II-2)

General formula (II-3)

Or general formula (II-4)

[In each general formula,
Boc is a tert-butoxycarbonyl group
X is carbon (CH) or nitrogen (N),
R ¹ , R ² and R ³ are independently selected from hydrogen, halogen, NO ₂ and lower alkyl groups (the alkyl groups are each independently _{selected from halogen, NO 2} and hydroxy groups). (May be substituted with a substituent of), an —O— lower alkyl group, each of which is independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups.} May be) or

The ring Y represents an azetidine ring, a benzene ring or a pyridine ring.
R ⁴ is a halogen, NO ₂ , lower alkyl group (the alkyl groups may be independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups), or} -O-Lower alkyl group, each of which may be independently substituted with one or more substituents selected from _{halogen, NO 2 and hydroxy groups.}
In R ^{1 to} R ⁴ , at least one of them is NO ₂ , a lower alkyl group (the alkyl group is _{substituted with at least one NO 2} ), or an -O- lower alkyl group (the alkyl group is at least one. It is replaced by one NO _2)]
A compound represented by (1) or a pharmaceutically acceptable salt or solvate thereof. A kit for preparing the labeled compound according to any one of claims 6 to 9, or a pharmaceutically acceptable salt or solvate thereof, and at least the compound according to claim 21 or. A kit containing the pharmaceutically acceptable salt or solvate.

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