WO2005042461A1 - Compound with amyloid affinity - Google Patents

Abstract

A novel technology capable of detection of amyloids, such as Aβ-protein occurring in Alzheimer disease, without the need for any special facilities. There is disclosed a styrylbenzene compound of the general formula (I). each of R1 and R2 independently is hydroxyl or carboxyl, and R3 is a fluorine or bromine atom. Necessarily when R3 is a bromine atom and optionally when R3 is a fluorine atom, at least one carbon atom among the carbon atoms constituting the carboxyls represented by R1 and R2 and the carbon atoms on α-, β-, Ϝ- and δ-positions is 13C. The compound of the formula (I) is not only capable of conducting fluorescent staining of amyloids but also functions as an amyloid-specific MRI contrast agent.

Description

 Specification

 Amyloid affinity compounds

 Technical field

 The present invention relates to a novel compound which belongs to the technical field of an in vivo test, and particularly has a affinity for amyloid involved in the onset and progress of Alzheimer's disease and the like, and is useful for the detection thereof.

 Background art

 [0002] The number of patients with Alzheimer's disease is said to be more than 1.5 million in Japan at present, and it is predicted that one out of every 10 elderly people will develop the disease 20 years later. The burden is increasing. The disease is hereditary, about 10%, and the remaining 90% are sporadic, with everyone at risk of developing the disease. It is characterized by the formation of senile plaques, neurofibrillary tangles, and atrophy of the brain. It is said that these organic changes have been progressing before clinical symptoms appear.

 [0003] At present, definitive diagnosis of Alzheimer's disease is based on histopathological examination of the postmortem brain.

 (Z. 5. Khachatunan, Arch.

Neurol., 1985, 42, 1097: Non-Patent Document 1), and Congo Red has been widely used as a tissue staining agent therefor. Congo Red has high affinity for amyloid β (sometimes abbreviated as Α) protein, a component of senile plaques, and can be selectively stained. In contrast, in vivo imaging probes for brain amyloid have recently appeared to capture the earliest neuropathological changes, the formation of senile plaques, before birth. Congo Red is a fluorescent molecule that has an affinity for the A protein, has a sulfone group in the molecule, and has high hydrophilicity, so it cannot cross the blood-brain barrier and cannot be used in vivo. Therefore, a low molecular compound of a hydrophobic with increased migration to the brain radionuclides (in ^{particular, "C, 13 N, 15} 0, 18 F) in labeled, PET (positron emission tomography) or SPECT ( Approaches to detection using computerized tomography with single-photon emitting nuclides have been studied, and thioflavin derivatives (eg, CA Mathis, et al, Bioorg. Med. Chem, Lett., 2002) have been used as probes for this in vivo imaging. , 12, 295: Non-Patent Document 2; MP Kung, et al., J. Mol. Neurosci., 2003,

 20, 15: Non-patent document 3; Z.—P. Zhuang, et al., J. Med. Chem., 2003, 46, 237: Non-patent document 4), etc. It also requires nuclear medicine facilities.

 [0004] A recently developed compound, BSB [(trans, trans) _1_bromo_2,5_bis_ (3-hydroxycarbonyl-2-hydroxy) styrylbenzene], recognizes the β-sheet structure of proteins. It has high affinity for β protein (Km = 0.4 M) and is expected to be a selective probe for diagnostic imaging of Alzheimer's disease because it fluorescently stains Aβ protein (DM Skovronsky et al., Proc. Natl. Acad. Sci., 2000, 97, 7609: Non-Patent Document 5). In the report by Non-Patent Document 5, BSB was intravenously administered to a model mouse of Alzheimer's disease, the mouse was sacrificed, and a brain specimen was stained after death. Good transfer to the brain was confirmed. When performing antemortem diagnosis with force, radiolabeling for detection by PET or SPECT is still necessary. BSB has also shown excellent staining results as a fluorescent stain for systemic amyloidosis (Y.

 Ando et al., Lab. Invest., 2003, in press .: Non-patent document 6).

 Non-patent document 1: Z.S.Khachaturian, Arch. Neurol., 1985, 42, 1097

 Non-patent document 2: CA Mathis, et al., Bioorg.Med.Chem, Lett., 2002, 12, 295 Non-patent document 3: MP Kung, et al., J. Mol. Neurosci., 2003, 20, 15

 Non-Patent Document 4: Z.-P. Zhuang, et al "J. Med. Chem., 2003, 46, 237

 Non-Patent Document 5: D.M.Skovronsky et al, Proc.Natl.Acad.Sci., 2000, 97, 7609 Non-Patent Document 6: Y.Ando et al., Lab.Invest., 2003, in press.

 Disclosure of the invention

 Problems to be solved by the invention

[0005] An object of the present invention is to establish a new technique that enables detection of amyloid such as A / 3 protein in Alzheimer's disease without requiring special equipment. Means for solving the problem

As a result of repeated studies, the present inventors have succeeded in developing a novel compound having BSB as a basic skeleton and having affinity for amyloid, and have derived the present invention. By virtue of the present invention, a styrylbenzene compound represented by the following general formula (I) is provided.

 [0007] [Formula 1]

[0008] In the formula (I), R and R are each independently a hydroxyl group or a carboxyl group. R

 123 is a fluorine atom or a bromine atom. When R is a bromine atom, R must be a fluorine atom

 3 3

 At the α-position, the γ-position, and the δ-position, and R and R

 At least one of the carbon atoms constituting the carboxy group of 12 is carbon-13.

 [0009] A preferred specific example of the compound represented by the formula (I) according to the present invention is a styrylbenzyl group represented by the formula (I), wherein R is a hydroxyl group, R is a carboxyl group, and R is a fluorine atom.

one two Three

 R is a hydroxyl group and R is a carboxy group in the formula (I)

 1 2

R is a bromine atom, and a styrylbenne in which the carbon atom at the _α- position and the -position is carbon-13

Three

 Powers of zen compounds include, but are not limited to, these.

 [0010] The compound of the above general formula (I) can fluorescently stain amyloid. Therefore, according to the present invention, there is provided a fluorescent dye for amyloid comprising the compound represented by the general formula (I). Is done.

 Further, the compound of the above general formula (I) can also be used as an MRI contrast agent having amyloid specificity. Therefore, according to the present invention, the compound represented by the general formula (I) An amyloid-specific MRI contrast agent is provided.

As is well known, the term amyloid used in the context of the present invention is a β-sheet structure (/ 3 folded structure) that leads to systemic amyloidosis or localized amyloidosis. The latter is representative of depositional proteins that also have secondary structural forces, and the latter, which belongs to focal amyloidosis, is due to the protein deposited on the brain of Alzheimer's disease patients as described above. The invention's effect

 [0012] The compound of the present invention represented by the formula (I) has a high affinity for amyloid similarly to conventionally known BSB and can fluorescently stain the protein, but is not limited thereto. It also functions as an MRI contrast agent with specificity for myloid.

 Brief Description of Drawings

 FIG. 1 shows a reaction scheme for synthesizing Example compounds (Compounds 1 and 9) of the present invention.

FIG. 2 shows a ¹⁹ F-NMR spectrum (A) of Compound 1 and a ¹³ C-NMR spectrum (B) of Compound 9.

 FIG. 3 shows the fluorescence spectra of compound 1, compound 9 and BSB.

 [Figure 4] Stained images of temporal cortical sections (fixed with ethanol) of postmortem brain of Alzheimer's disease patient, (A) stained with compound 1, (B) with compound 9, and (C) with BSB. Indicates the case.

 FIG. 5 is a stained image of a frontal cortical slice (fixed with ethanol) of a postmortem brain of an Alzheimer's disease patient, (A) showing a case stained with compound 1 and (B) showing a case stained with compound 9.

FIG. 6 shows an in vivo ¹⁹ F-MR brain image obtained when Compound 1 according to the present invention was administered to amyloid precursor protein transgenic mice.

FIG. 7 shows a ¹ H-MR brain image of a mouse brain which has been subjected to ¹⁹ F_MRI measurement and removed and fixed.

 BEST MODE FOR CARRYING OUT THE INVENTION

The styrylbenzene compound of the present invention represented by the formula (I) can be synthesized by devising various reactions. FIG. 1 illustrates a preferred reaction scheme for synthesizing a styrylbenzene compound of the present invention. Briefly, as shown, as shown, OMe or --CO Me (Me is methyl Group) and a phosphonic acid-derived group _P (0) (OEt) (Et is an ethyl group) substituted at both ends with fluorine or bromine and substituted with benzaldehyde (compound indicated by 8 in Fig. 1) P-xylene-hi, hi-

 2

 The compound is reacted with the compound to form a distyrylbenzene structure serving as a skeleton (step d in FIG. 1), and then sequentially demethylated to obtain a compound of the formula (I).

In the formula (I), when R is a bromine atom, the carbon atom at the _α- position, the position, the γ-position, and the δ-position

 Three

And at least one of the carbon atoms constituting the carboxy group of R and R is carbon 13 ( ¹³ C). On the other hand, when R is a fluorine atom,

 Three

 At least one of the carbon atoms does not have to be carbon 13, i.e., the carbon atoms constituting the carboxyl group at the l-, j3-, γ- and δ-positions and the carboxyl group of R and R are ordinary carbon 12

 1 2

 May be used. The thus-obtained compound of the present invention represented by the formula (I) has an amyloid-specific MRI (magnetic resonance imaging) contrast agent having fluorine and Ζ or carbon 13 in the molecule and having specificity for amyloid. In this respect, it has features not found in the conventionally known BSB.

[0016] Furthermore, the compounds of the present invention represented by the formula (I) are, similarly to BSB, those having high affinity for amyloid by brain amyloid (protein) and systemic amyloidosis. Miloid can also be fluorescently stained. In this case, the formula (I) in which R is a fluorine atom is particularly

 Three

 In some cases, the fluorescence intensity is increased about twice as compared with BSB, in which the fluorescence intensity is high. This is understood because the compound (I) having a fluorine atom in the molecule has no fluorescence quenching due to the heavy atom effect as compared with BSB.

 Hereinafter, examples will be described in order to more specifically show the features of the present invention, but the present invention is not limited to these examples.

 Example 1

 Synthesis Example 1: As an example of the compound of the present invention represented by the formula (I), in the formula (I), R is a hydroxyl group,

 Is a carboxyl group, and R is a fluorine atom.

twenty three

 Synthesized. The operation in each step and the obtained product identification data are shown below in order.

 <Synthesis of Intermediate 3>

2,5-Dimethylaniline (10 g, 82 mmol) was suspended in water (30 ml), and concentrated hydrochloric acid (17 ml) was added little by little. After cooling to about 5 ° C, an aqueous solution of sodium nitrite (a solution of 7.0 g dissolved in 10 ml of water; lOlmmol) was added dropwise. The mixture was stirred for 1 hour as it was, and the insoluble material was separated by filtration. To the filtrate was added sodium borofluoride (11.0 g, 10 mmol), and the precipitated diazodium salt was collected by filtration. This was heated and decomposed, and the separated oil was purified by a silica gel column (hexane) to obtain 1.51 g (yield: 15%) of the desired product. Colorless oil. ^{J H NMR (CDCl): 5} 2.22 (s, 3H)ゝ2.30 (s, 3H),

 Three

6.79- 6.83 (m, 2H) ゝ 7.03 (t, J = 8.0Ηζ, 1Η); ¹⁹ F-NMR (CDC1): —118.5 ppm.

 Three

[0018] <Synthesis of Intermediate 4> Intermediate 3 (1.02 g, 8.2 mmol) was dissolved in chloroform (100 ml), and N-bromosuccinimide (3.1 g, 17.4 mmol) and 2,2,1-azobis (isobutyronitrile) (10 mg, 0.06 mmol) ) Was added and the mixture was heated under reflux for 100 minutes. After standing to cool, the pore-form layer was washed with water, dried (MgSO 4) and concentrated under reduced pressure

4 Hexane was added to the residue for crystallization. Yield 0.99 g (43% yield). White crystalline powder. 'Η NMR (CDCl): δ 4.43 (s, 2H), 4.49 (s, 2H), 7.08_7.41 (m, 3H); ¹⁹ F_NMR (CDC1): —

 3 3

115.9OTm; MS: m / z 281 (M + l).

<Synthesis of Intermediate 5>

 Intermediate 4 (0.99 g, 3.5 mmol) and triethyl phosphite (1.16

 g, 7.0 mmol) and heated at 160 ° C. for 4 hours. After completion of the reaction, the oil obtained by concentration under reduced pressure was purified by a silica gel column (methylene chloride: methanol = 95: 5 (v / v)) to give 1.18 g (yield: 85%) of the desired product. Colorless oil. 'Η NMR (CDCl): δ 1.23 _1.29 (m, 12H),

 Three

 3.11 (d, J = 20.3Hz, 2H) ゝ 3.17 (d, J = 20.6Hz, 2H), 3.98— 4.10 (m, 8H),

7.04 (d, J = 9.9Hz, lH), 7.27- 7.34 (m, 2H); 19 F- NMR (CDC1): -117.1 Rabbit m; MS:

 Three

m / z397 (M + l) ₀

<Synthesis of Intermediate 6>

 Intermediate 5 (1.18 g, 3.0 mmol) was dissolved in anhydrous methanol (5 ml), and compound 8 (1.16 g, 6.0 mmol) was added. After cooling to 0 ° C., a 28% sodium methoxide methanol solution (2 ml) was added dropwise, and the mixture was heated under reflux overnight. After cooling, the precipitate was collected by filtration. The obtained yellow solid was suspended in water (100 ml) and adjusted to about pH 3 with 1M hydrochloric acid. It was extracted with black-mouthed form, the black-mouthed form layer was washed with water, dried (MgSO 4), and concentrated to dryness. Silica gel column purification (clo form: vinegar

 Four

After 9: 1 ( _ν / ν)), 0.42 g (yield 30%) of the desired product was obtained. Yellow powder.

 NMR (CDCl): δ 3.93 (s, 6H), 3.94 (s, 6H), 6.94_7.26 (m, 8H), 7.55 (t, J = 7.9Hz, lH),

 Three

 7.61 (dd, J = 9.1,2.2Hz, lH), 7.64 (dd, J = 9.3,2.2Hz, lH), 7.97 (d, J = 2.2Hz, lH),

7.98 (d, J = 2.2 Hz, lH); ¹⁹ F-NMR (CDC1): — 118. lppm; MS: m / z 476 (M ⁺ ) ₀

 Three

 <Synthesis of Intermediate 7>

Intermediate 6 (0.42 g, 0.87 mmol) was dissolved in methylene chloride (50 ml) and cooled to -78 ° C. A 1.0 M boron tribromide-dichloromethane solution (9 ml, 9.0 mmol) was added dropwise, and the mixture was stirred at room temperature overnight. Cool in an ice bath, add water (30 ml), add about 10% methanol, add methylene chloride layer Was collected. Further, the aqueous layer was extracted with methylene chloride. The methylene chloride layers were combined, dried (MgSO 4), and concentrated under reduced pressure to obtain 0.39 g (yield 100%) of the desired product. Yellow powder.

 Four

 NMR (DMSO-d): δ 3.93 (s, 6H), 7.03 (d, J = 8.7Hz, lH), 7.04 (dJ = 8.5Hz, lH),

 7.15 (d, J = 16.5Hz, lH), 7.16 (dJ = 16.5Hz, lH), 7.36 (d, J = 16.5Hz, lH),

7.37 (d, J = 16.5 Hz, lH), 7.43-7.52 (m, 2H), 7.75-7.89 (m, 3H), 7.98 (s, 2H), 10.59 (s, 2H); ¹⁹ F-NMR ( DMSO_d): _118.6ppm.

 <Synthesis of Compound 1>

 Intermediate 7 (0.42 g, 0.94 mmol) was suspended in a 0.06 M aqueous potassium hydroxide solution (150 ml, 9.3 mmol) and heated under reflux for 4 hours. 6 M hydrochloric acid (10 ml) was added little by little to adjust the pH to about 2. After cooling, the precipitate was collected by filtration to obtain 0.23 g of the desired product (yield from intermediate 6: 64%). Yellow powder. mp294 ° CCdecomp.); ^

 NMR (DMSO-d): δ 6.95 (d, J = 8.5Hz, lH), 6.96 (dJ = 8.5Hz, lH), 7.12 (d, J = 16.2Hz, lH)

, 7.13 (d, J = 16.5Hz, lH), 7.33 (d, J = 16.5Hz, lH), 7.34 (d, J = 16.2Hz, lH),

 7.42-7.49 (m, 2H), 7.74_7.76 (m, lH), 7.79 (dJ = 8.8Hz, lH), 7.80 (dJ = 8.8Hz, lH),

7.98 (d, J = 2.2 Hz, lH), 8.00 (d, J = 2.2 Hz, lH); ¹⁹ F NMR (DMSO-d): -118.7 ppm (s); MS: m / z 419 (Ml); IR (KBr): 3430 (OH), 3025 (CO H) ゝ 1670 (C = O), 1210, 1190, 955cm

As shown in the above data and FIG. 2A, Compound 1 expresses a single large peak at −118.5 m in ¹⁹ F_NMR, and is capable of imaging with ¹⁹ F_NMR. It was confirmed that there was.

 Example 2

 Synthesis Example 2: As an example of the compound of the present invention represented by the formula (I), in the formula (I), R is a hydroxyl group, R is a carboxyl group, R is a bromine atom, Carbon at position 13

twenty three

 Was synthesized according to the scheme shown in FIG. The operation in each step and the identification data of the obtained product are shown below in order.

<Synthesis of Intermediate 8>

5_Formylsalicylic acid (22.0 g, 132.4 mmol) was dissolved in acetone (1.1 L) while heating, and potassium carbonate (36.5 g, 264.1 mmol) was added. Methyl iodide (253.4 g, 1.78 mol) was added for 2 hours. Divide every other The mixture was stirred at 50 ° C for 12 hours. After cooling, the solvent was distilled off, water (200 ml) was added, and the insoluble matter was collected by filtration. After recrystallization from ethanol (300 ml), 16.59 g (yield 65%) of the desired product was obtained. White needle crystals. 'Η NMR (CDCl): δ 3.93 (s, 3H), 4.06 (s, 3H), 7.12 (d, J = 8.7Hz, lH),

 Three

 8.03 (dd, J = 8.5, 2.2 Hz, lH), 8.33 (d, J = 2.1 Hz, lH), 9.92 (s, lH).

<Synthesis of Intermediate 11>

 Synthesis of complex ferrosenium 'tetrakis [3,5-bis (trifluoromethyl) phenyl] borate] f. (H. Kitagawa et al., Bull. Chem. Soc. Jpn., 2002,

75, 339), and was synthesized from ferrosenium 'tetrafluoroborate in a yield of 64%. Ferrosendium 'tetrakis [3,5_bis (trifluoromethyl) phenyl] borate (0.49 g, 0.46 mmol) and zinc oxide (0.84 g, 10.3 mmol) were dissolved in methylene chloride (5 ml), and bromine (1.65 g, 10.3 mmol), and the mixture was stirred at room temperature for about 1 hour. p-xylene α, α, ^13C (

 2

1.0 g, 9.2 mmol) was dissolved in methylene chloride (10 ml), cooled to -50 ° C, and the above solution was added dropwise. The mixture was changed to an ice bath and stirred for 1.5 hours. The ethyl acetate was dried and washed with saturated sodium thiosulfate. The ethyl acetate layer was washed with water, dried (MgSO 4), and the solvent was distilled off. The residue

 Four

 Purification (hexane) by a silica gel column gave 1.03 g (yield 59%) of the desired product. Colorless oil. ¾ NMR (CDCl): δ 2.28 (d, J = 127.0 Hz, 3H) ゝ 2.33 (d, J = 127.0 Hz, 3H),

 Three

6.99 (dd, J = 7.7,4.1Hz, lH), 7.09 (dd, J = 7.7,4.7Hz, lH), 7.34 (d, J = 4.4Hz, lH) ₀

<Synthesis of Intermediate 12>

 Intermediate 1 was synthesized by the same method as Intermediate 4 (yield 43%). White crystalline powder. NMR (CDCl): δ 4.41 (d, J = 154.0 Hz, 2H), 4.58 (d, J = 154.0 Hz, 2H),

 Three

 7.32 (ddd, J = 7.7, 4.7, 1.7 Hz, lH), 7.43 (dd, J = 7.7, 4.7 Hz, lH), 7.61 (dd, J = 5.5, 1.7 Hz, lH).

 <Synthesis of Intermediate 13>

 Synthesized from Intermediate 12 in the same manner as Intermediate 5 (94% yield). Yellow oil. 'Η NMR (CDCl): δ 1.25 (t, J = 7.1Hz, 12H), 3.08 (dd, J = 128.0,21.0Hz, 2H),

 Three

 3.37 (dd, J = 128.0,21.0Hz, 2H), 3.98-4.09 (m, 8H), 7.20_7.26 (m, lH), 7.39-7.43 (m, lH), 7.50-7.52 (m, lH) .

 <Synthesis of Intermediate 14>

Synthesized from Intermediate 13 in the same manner as Intermediate 6 (50% yield). Yellow powder. H NMR (CDCl): δ 3.93 (s, 6H), 3.94 (s, 6H), 6.94 (dd, J = 154.0, 16.0 Hz, lH),

6.98-7.14 (m, 4H), 7.43_7.45 (m, lH), 7.60-7.72 (m, 5H), 7.97 (s, lH), 7.98 (s, lH). As shown in the B above data and Figure 2, the compound 9 is expressed significant peaks at 124.8 Rabbit m and 125.5ppm in ¹³ C_NMR, contrast by ¹³ C_MRI (images in g) is possible Was confirmed. The peak around 40 m in B of FIG. 2 is the peak of the solvent (DMSO_d).

 Example 3

 Measurement of Fluorescence Properties: Fluorescence spectra were measured for Compound 1 synthesized in Example 1 and Compound 9 synthesized in Example 2, and BSB for comparison. The equipment used for the measurement is

 HITACHI F-4500. The measured concentrations were 1 μM each (in DMSO), and the wavelength of the excitation light was 390 nm.

 Figure 3 shows the measurement results. As shown in FIG. 3, the compounds 1 and 9 of the present invention express strong fluorescence at 511 nm and 521 nm like BSB. In particular, Compound 1, which has fluorine in the molecule, has about twice the fluorescence intensity as compared to BSB.

 Example 4

 [0031] Brain amyloid staining: Brain amyloid was stained using compound 1 synthesized in Example 1 and compound 9 synthesized in Example 2, and BSB for comparison.

Staining was performed according to the method described in Non-Patent Document 5 (DM Skovronsky et al., Proc. Natl. Acad. ScL, 2000, 97, 7609). That is, post-mortem brains of Alzheimer's disease patients (4 cases) were fixed in 150% NaCl-containing 70% ethanol or 10% neutral buffer in formalin (NBF), and 6-μμη paraffin sections were prepared by a conventional method. The sections were immersed in a 0.01% solution of compound 1, compound 9 or BSB in 50% ethanol for 30 minutes, and then immersed in a saturated aqueous solution of lithium carbonate. Washed with 50% ethanol and observed with a fluorescence microscope (V-excited UV light) FIGS. 4 and 5 show stained images (photographs) observed with a fluorescence microscope. FIG. 4 shows a stained image of a temporal cortex section fixed with ethanol, and FIG. 5 shows a stained image of a frontal cortex section (semi-connected slice) fixed with ethanol. The images in FIGS. 4 and 5 are actually color images, In order to clearly show the signs, traces of the fluorescent areas are shown below each photographic image. It is understood that the compounds 1 and 9 of the present invention have an affinity for the A / 3 protein constituting the senile plaque and selectively fluorescently stain the protein. FIG. 5 shows the same sample stained using Compounds 1 and 9, and the same number in the figure indicates that the sample is derived from the senile plaque in the same place.

 Example 5

 This Example shows that the compound of the present invention represented by the formula (I) functions as an amyloid-specific MRI contrast agent. Using compound 1 synthesized in Example 1 (hereinafter referred to as FSB in this example), MRI measurement was performed as follows.

 Amyloid precursor protein transgenic mouse (Tg2576.

Hsiao et al., Science, 274, 99 (1996)), anesthetized, and administer 20 μg / kg of PBS containing 0.2% FSB and 10% DMSO 500 μl via tail vein over 150 min. did. Three hours later, a ¹⁹ F-MRI scan of the mouse head was performed in vivo (with the mouse alive). ¹⁹ The brain image of F-MR is 3D-RARE (3D-RARE

 spin echo Rapid Acquisition with Relaxation Enhancement) / j: Oh, the MRI system for Bruker AVANCE 400WB imaging

 spectrometer (Bruker BioSpm

 GmbH).

The obtained brain image photograph of ¹⁹ F-MR is shown in FIG. 6 (1). Spots presumed to be senile plaques were detected as high signal areas in the ¹⁹ F-MR image (white spots in FIG. 6 (1)). Note that FIG. 6 (1) is actually a color image, and the spot-like portions are observed as clear red light-emitting portions. Fig. 6 (2) shows the photograph of Fig. 6 (1) by hand to facilitate understanding of Fig. 6 (1).

[0033] Further, as described above, brains were removed from mice ¹⁹ F-MRI scan, after overnight fixation in 4% paraformaldehyde, and embedded in 3% aqueous Agarosugeru, T2- emphasis RARE ^ -MR image Was obtained. The obtained ¹ H-MR brain image photograph is shown in FIG. 7 (1). In addition, FIG. 7 (2) shows a photograph of FIG. 7 (1) traced by hand to facilitate understanding of FIG. 7 (1). As shown in FIG. 7, the parts corresponding to FIG. 6 (indicated by arrowheads in FIGS. 6 and 7) can also be obtained by ^ -MRI. A T2-weighted image signal is obtained in the area shown in Fig. 6, and it is understood that the spot-like part shown in Fig. 6 is a senile plaque. Furthermore, it has been shown that ¹⁹ F-MRI in vivo can detect senile plaques with higher sensitivity than ¹ H-MRI of post-mortem brain depending on the part of the brain (for example, the circled part in FIG. 6). Furthermore, frozen brain was MRI measured as described above, 40 zm create a thick cryosections was observed intracerebral distribution of FSB by fluorescence microscopy, ¹⁹ F-MRI, as shown in FIG. 6 The abnormal part (spotted part) found in the above was found to have been detected as a result of the accumulation of FSB in lesions that could be morphologically confirmed as senile plaques.

Industrial applicability

 The compound of the present invention can be used as a fluorescent staining agent for amyloid derived from systemic amyloidosis and local amyloidosis, for example, in histopathological examination of amyloid-related diseases represented by Alzheimer's disease. it can.

 Furthermore, since the compound of the present invention also functions as an MRI contrast agent having amyloid specificity, as a simple method using MRI widely used in medical institutions, amyloid correlation such as Alheimer's disease can be used. It can also be used for prenatal diagnosis of disease.

Claims

Claims [1] A styrylbenzene compound represented by the following general formula (I).  [Chemical 1]

[In the formula (I), R and R are each independently a hydroxyl group or a carboxyl group;  1 2  Is a fluorine atom or a bromine atom, and whenever R is a bromine atom, R is a fluorine atom In the case of a 3 3 element, carbon atoms at the α-position, the γ-position, and the δ-position, and R and R  At least one of the carbon atoms constituting the carboxy group of 12 is carbon-13. ]  [2] In the formula (I), R is a hydroxyl group, R is a carboxyl group, and R is a fluorine atom.  one two Three  2. The styrylbenzene compound according to claim 1.  [3] In the formula (I), R is a hydroxyl group, R is a carboxy group, and R is a bromine atom.  one two Three  2. The styrylbenzene compound according to claim 1, wherein the carbon atoms at the 2- and / 3-positions are carbon-13.  [4] A fluorescent dye for amyloid, comprising the compound represented by the general formula (I) according to claim 1. [5] An amyloid-specific MRI contrast agent comprising the compound represented by the general formula (I) according to claim 1.