JPH0395166A - Isoxazolone derivative-containing ameliorant for cerebral function - Google Patents

Abstract

PURPOSE:To obtain the subject ameliorant, containing an isoxazolone derivative as an active ingredient, capable of activating mammalian nerve cells, promoting hypermnesia with low toxicity and effective against dysmnesia due to cerebral apoplexy, Alzherimer's diseases, head injuries, etc. CONSTITUTION:An ameliorant containing a compound expressed by formula I (R<1> is H or lower alkyl; R<2> is amino which may be protected; COR<3> is carboxyl which may be esterified; (n) is 0-3) as an active ingredient. In use, the aforementioned compound is mixed with a pharmaceutically acceptable carrier and used in a dosage form of tablet, pellet, injection, etc. Furthermore, the compound expressed by formula I which is the active ingredient is synthesized by reacting, e.g. a compound expressed by formula II (COOR<4> is esterified carboxyl group) with hydroxylamine and subjecting the resultant product to cyclizing reaction. The compound expressed by formula II is synthesized by using an epsilon-carboxyl-alpha-amino acid derivative and carbonyldiimidazole as starting raw materials.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel inxazolone derivative-containing brain function improving agent useful as a pharmaceutical.

Conventional technology With the rapid increase in the elderly population, the disease structure is also undergoing major changes. Among geriatric diseases, senile dementia is also socially important.
It is also one of the most important medical issues to consider. One of the medical measures against this senile dementia is the development of therapeutic drugs. As a treatment for senile dementia, ``C'' has been used as a cerebral circulation/metabolism improving agent and a drug that improves the function of neurotransmitters in the brain.

Problems to be Solved by the Invention However, the current situation is that none of the conventionally used drugs for treating senile dementia have a satisfactory clinical effect.

The present invention provides a drug that improves the functions of cerebral circulation and metabolism and intracerebral neurotransmission.

Means for Solving the Problems Another physiological finding for overcoming the above problems is that excitatory amino acids in the brain, particularly glutamate, play an important role in shaping memory. Glutamate receptors in the brain are mainly classified into three subtypes: NMDA (N-methyl-D-asbartate) type, Kiskare-Ito type, and Kainate type. Among these receptors, it is speculated that the action of glutamate on NMDA type receptors is particularly important for memory formation. This speculation is based on the phenomenon of long-term potentiation (long-term potentiation) in the hippocampus in the brain.
It is based on an important new medical finding that the stimulation of NMDA-type receptors by glutamate is involved in the mechanism by which glutamate potentiation occurs.

[Taylor, T. J. and Discen
na. Annual 0 Review●of●Neuroscience (P. ;゛Ann. Rev.Naurosci.
), l O : l 3 1 − 1 6 1 .
1 9 8 7 Cotman, C. W. and Mon
agham. D. T. ; Ann. Rev. Neur
osci. ．． l l:6 1-8 0.1 9 8 8
] However, since the involvement of other subtype receptors cannot be ruled out, the present inventors investigated the affinity for brain glutamate receptors including the three subtypes, activation of hippocampal neurons, and memory impairment. An experimental system was established to prove the effectiveness of the model.

Next, the present inventors succeeded in the chemical synthesis of an inxazolone derivative represented by the following formula. The present inventors have also discovered that the inxazolone derivative has a strong affinity for the above-mentioned glutamate receptor and is useful as a brain function improving agent.

That is, the present invention provides the following formula: Each represents an integer of ~3. ] or a salt thereof, and a brain function improving agent containing a compound represented by the formula (2) [wherein R1 is hydrogen or a lower alkyl group, R2 is an optionally protected amino group, COR3 represents a carboxyl group which may be esterified, and n represents an integer of O to 3. However, n is 2, R1 is hydrogen, and R
! Excludes compounds where is NH2 and COR3 is a carboxyl group. ] or a salt thereof.

Regarding the above formula (I), examples of the lower alkyl group represented by Rl include methyl, ethyl, probyl, isobrobyl, butyl, isobutyl, sec-butyl, ta
Examples include alkyl groups having about 1 to 4 carbon atoms such as rt-butyl, and methyl is particularly preferred.

As the protecting group for the optionally protected amino group represented by R2, those known as protecting groups for amino groups are used, such as lower (C+-S) alkanoyl (eg, acetyl, propionyl), benzoyl. 7 enyl lower grade (
C+-)alkoxycarbonyl (e.g. penzyloquinecarbonyl). Lower (CI-4) alkoxy carbonyl (
For example, acyl groups such as tert-ptoxycarponyl),
Examples include aralkyl groups such as benzyl and trityl, with tert-butoxy carbonyl being preferred.

Esterified I represented by COR'; Examples of the carpoxyl group include lower (C+-a) alkoxy such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, ingropoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl, etc. Examples include tonophenyl lower (CL-,)alkoxycarbonyl groups, penzyloxycarbonyl, α-phenethyloxycarbonyl, β-phenethyloxycarbonyl, phenylbutyloxycarponyl, phenylbutyloxycarbonyl, and tonophenyl lower (C L-,)alkoxycarbonyl groups. However, methoxycarbonyl is preferred.

Specific examples of the compounds of the present invention include the following compounds.

Table 1 The compound (I) of the present invention has an asymmetric carbon in the molecule, but R
Both the configuration and the S configuration are included in the present invention.

Examples of the salt of compound (I) include hydrochloride, hydrobromide. Sulfates, nitrates. Inorganic acid salts such as phosphates, e.g. acetates, tartrates, citrates, fumarates,
Organic acid salts such as maleate, toluenesulfonate, methanesulfonate; metal salts such as sodium salt, potassium salt, calcium salt, aluminum salt,
For example, triethylamine salt, guanidine salt. Examples include salts with bases such as ammonium salts, hydrazine salts, quinine salts, and cinunidine salts, but any pharmacologically acceptable salts may be used.

Compounds of the present invention (D is, for example, 2〇〇p1 [wherein R', R2, C O R'', n have the same meanings as above.

C○○R4 represents an esterified carboxyl group.

It can be produced by reacting a compound represented by the following with hydroxylamine or a salt thereof and subjecting it to a ring-closing reaction. Examples of the esterified carboxyl group represented by COOR' include the same carboxyl groups as described above for COR'. Preferred conditions for the ring-closing reaction include, for example, compound (II) in a water-containing solvent such as dioxane water, tetrahydrofuran water,
Alternatively, it is dissolved in an alcoholic solvent such as methanol or ethanol, and about 1 to 3 equivalents, preferably about 1.2 to 2.0 equivalents of hydroxylamine or its salt are added. The reaction temperature is preferably about O0C to the reflux temperature of the solvent, and the reaction time is preferably about 10 minutes to 5 hours. In this reaction, a base such as potassium carbonate, sodium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium hydroxide, potassium hydroxide, etc. can also be present in the reaction system.

A compound in which COR3 in formula (I) is a carboxyl group,
For example, formula (III) [wherein COR'' represents an esterified carboxyl group, and R', R'' and n have the same meanings as above. It can also be produced by subjecting a compound represented by the following to a deprotection reaction. Examples of the esterified carboxyl group represented by "COR" include those similar to the carboxyl group described above for COR'. The deprotection reaction may be performed using an acid or base method depending on the type of the protecting group. In the case of using an acid, the acid may be selected depending on the type of protecting group and other conditions, but examples of the acid include hydrochloric acid, hydrogen bromide, hydrogen fluoride, hydrogen iodide, and methanesulfone. acid.p-}luenesulfonic acid,
Trifluoromethanesulfone LML phosphate. Formic acid, acetic acid,
In addition to trifluoroacetic acid, acidic ion exchange resins and the like are used. In the case of a method using a base, the base may be an alkali metal such as sodium or potassium, or calcium. hydroxides of alkaline earth metals such as magnesium,
In addition to inorganic bases such as carbonates, metal alkoxides, organic amines, organic bases such as quaternary ammonium salts, basic ion exchange resins, etc. are used. When a solvent is used in the above acid or base method, for example, water. methanol. Ethanol, ethyl acetate, chloroform, tetrahydrofuran, dioxane. Single pyridine, acetic acid, acetone, methylene chloride, etc. Alternatively, they can be used in combination. The reaction temperature is usually cooled or warmed, and the reaction time is about 30 minutes to 24 minutes.
It's time.

The compound in which R2 in formula (1) is an amino group is, for example, the formula (■) [wherein R2' represents a protected amino group, and R1,C
OR'', n has the same meaning as above. It can also be produced by subjecting the compound represented by 1 to a deprotection reaction.R
As a protecting group for the protected amino group represented by 2',
The same protecting groups as mentioned above for R2 can be mentioned. As for the deprotection reaction, depending on the type of the protecting group,
A method using an acid or a base can be selected as appropriate. In the case of using an acid, it varies depending on the type of protecting group and other conditions, but examples of the acid include hydrochloric acid. Hydrogen bromide. Hydrogen fluoride. Hydrogen iodide, methanesulfonic acid, p
monotoluenesulfonic acid, trifluoromethanesulfonic acid,
Sulfuric acid, phosphoric acid, formic acid. In addition to acetic acid, tri7fluoroacetic acid, etc., acidic ion exchange resins and the like are used.

In the case of a method using a base, it depends on the type of protecting group and other conditions, but as a base, for example, sodium,
In addition to inorganic bases such as hydroxides and carbonates of alkali metals such as potassium or alkaline earth metals such as calcium and magnesium, organic bases such as metal alkoxides, organic amines, and quaternary ammonium salts, as well as basic ions. Replacement resin etc. are used. When a solvent is used in the above acid or base method, for example, water. methanol. Ethanol, ethyl acetate. Chloroform, tetrahydro7rane, dioxane, pyridine, acetic acid, acetone, methylene chloride, etc. can be used singly or in combination. The reaction temperature is usually cooled to warm, and the reaction time is about 30 minutes to 24 hours.

That is, the types of protecting groups for amino groups and carpoxy groups, how to introduce them, and how to remove them after the desired reaction are well known, and in the present invention, You can follow it.

The compound of the present invention is 4,5-dihydro-5-okine-3
-Inxazolyl compound (V) may also exist.

The above formula (1) and formula (V) are tautomers, and exist in the form of either one or a mixture of the two depending on the conditions under which the substance exists.

The object compound (I) of the present invention thus obtained is separated and purified from the reaction mixture by conventional separation and purification methods such as extraction, concentration, neutralization, filtration, recrystallization, column chromatography, etc. It can be isolated by using means such as thin layer chromatography.

Compound (1) may exist in at least two stereoisomers. Naturally, both of these individual isomers and mixtures thereof are included within the scope of the present invention, and if desired, these isomers can also be produced individually by means known per se.

For example, starting compound CI[). (I[[) and (IV
), a single optical isomer of compound (I) can be obtained by carrying out the above reaction using a single isomer of each compound (I), and the raw material can also be a mixture of two or more isomers. In this case, this can be carried out using conventional separation methods such as optically active acids (e.g., cyanazulfonic acid, tartaric acid, dibenzoyltartaric acid, etc.), optically active bases (e.g., cinchonine, cinchonidine, quinine, quinidine, α-methylbenzylamine, etc.). , dehydroabietynoleamine, etc.) and various chromatography methods. It can also be separated into each isomer by separation means such as fractional recrystallization.

The starting material compound (I[) of the present invention can be easily produced, for example, by the following reaction.

[In the above reaction formula, the symbols have the same meanings as above. The compound (I ) is reacted with carbonyldiimidazole and then reacted with malonic acid monoester derivative magnesium salt (■) to obtain compound (■)'. In this reaction, compound (VI) is mixed with an organic solvent such as tetrahydrofuran, diethyl ether, n-hexane. Dissolved in acetonitrile or a mixture thereof at a temperature of about -1
At 0° C. to 50° C., preferably around room temperature, carbonyldiimidazole is added and maintained for about 10 minutes to 24 hours, preferably about 1 hour to 10 hours. Then, a magnesium salt represented by the formula (■) is added to the reaction solution, and the reaction is carried out at a reaction temperature of about 10°C to 50°C, preferably around room temperature, for about 1 hour to 48 hours, preferably about 10 hours to 24 hours. let

The compound (■)' thus obtained can be subjected to the deprotection reaction of the amino group as described above, if desired, to lead to (II).

As mentioned above, compound (I) and its salts activate nerve cells in mammalian animals (e.g., rats, monkeys, humans), promote memory improvement, and have low toxicity, making them useful as brain function improving agents. It is. In other words, the main target diseases are stroke and Alzheimer's disease, but head trauma. It is also useful for memory disorders (decline in intellectual function) caused by hydrocephalus and other causes.

When the compound of the present invention or a salt thereof is used as a brain function improving agent, the therapeutic agent can be obtained by mixing the compound or a salt thereof with a pharmacologically acceptable carrier. Effective preparations include tablets, pellets, 2 capsules, suppositories, liquids, and emulsions. It can be used in suspensions and other pharmaceutically suitable dosage forms.

For example, when manufacturing oral therapeutic agents, appropriate amounts of binders (e.g., hydroxypropylcellulose, hydroxypropylmethylcellulose, macrogol, etc.), disintegrants (e.g., starch, carboxymethylcellulose calcium, etc.), etc.), excipients (eg, lactose, starch, etc.), and lubricants (eg, magnesium stearate, talc, etc.).

When manufacturing parenteral therapeutic agents, such as injections, isotonizing agents (e.g., glucose, D-sorbitol, D-mannitol, sodium chloride, etc.), preservatives (e.g., benzyl alcohol, chlorobutanol, Methyl benzoate, provil parahydroxybenzoate, etc.) and buffers (eg, phosphate buffer, sodium acetate buffer, etc.) are used.

Next, the method for administering the salt of the compound of the present invention will be described.

For example, the compound of the present invention or a salt thereof may be administered parenterally as an injection to the above-mentioned dairy animals subcutaneously, intravenously, or intramuscularly at approximately 0%
．． OL to 20 mg/kg/a, preferably about 0.1 to 5 mg/kg per day. Well;
Orally, the compound of the present invention or a salt thereof is prepared as a capsule, and the dose of the compound of the present invention is 0.02 to 100 mg.
/kg/day, preferably about 0.1 to 20mg/kg
Administer /day.

Examples Example 1 (S)-N-tart at room temperature in a stream of argon
-N,N'-Carponyldiimidazole (914mg.5.64mmol) was added to a solution of -butoxycarbonylaspartic acid α-methyl ester (1.17g.4.72mmol) in tetrahydrofuran (25d), and 6 Stir for hours. Magnesium salt of malonic acid monomethyl ester (1.21g, 4.70g) was added to the reaction solution.
mmof) was added and stirred at room temperature for 18 hours. The reaction solution was concentrated and dissolved in ethyl acetate (50 ml2), water was added, and insoluble matter was removed by filtration. The filtrate was extracted with ethyl acetate, and the extract was washed successively with IN hydrochloric acid, water, saturated aqueous sodium bicarbonate, water, and saturated brine, dried (sodium sulfate), and the solvent was distilled off. When the residue was subjected to silica gel column chromatography (2.5 cm x 40 cm; ethyl acetate-hexane-l:3→1:2-t;l), (S)-2-tert-ptoxylponylamino-4-oxo1 was obtained. .6-hexanedioic acid dimethyl ester (1.32 g.92%) was obtained as colorless prism crystals.

mp48-49℃ Elemental analysis value C 13H ztN O y calculated value C
51.48; H 6.98; N 4.62 Actual value C 51.34; H 7.12; N 4.
58I R y KB'CKQ-': 3390.
2990. 1750, 1720, 1680, ma
x 1510, 1440. 1370. 'H NMR (CDCQ3) δppm: 1.45 (
98, s). 3.10 (IH.dd, J-4.4.1
8.4Hz). 3.28 (IH, dd. J-4.4.
1.85Hz). 3.49 (2H.s). 3.74
(3H.s). 3.75 (3H, s). 4.45 (I
H, m), 5.47 (IH, m). Light intensity Ea]r
- 15-8° (c-0.57, methanol) in an argon stream (S) - 2-tert-butoxycarpo-
Nylamino-4-oxo 1,6-hexanedioic acid dimethyl ester (1.21g, 4.00mmol)
Hydroxylamine (
2 7 8mg. 4. 00 mmol) and sodium carbonate (212 mg, 2.00 mmol) were added, and the mixture was heated under reflux for 1 hour.

Insoluble materials were filtered off, the filtrate was concentrated, and the residue was subjected to silica gel column chromatography (2.5 cm x 40 cm).
; When subjected to ethyl acetate-hexane-2:141 ethyl-acetic acid e ethyl-methanol = 9:1), compound 1 (5 2
9 mg, 46%) was obtained as a pale yellow foam.

I R v n08tcm-': 3360, 299
Lj. 1800. 1740, 1710. maX 1510, 1440, 1370. 'H-NMR (CDCJ) δppm: 1.44 (9H
, s). 2.83 (IH, dd, J=15.7.8H
z), 3-01 (lH.dd, J-5.15Hz).
3.40 (l}I, d, J-23.4Hz), 3.6
9 (LH.d, J-23.4Hz). 3.81 (3H,
s), 4.61 (IH, m), 5.43 (IH, d
, J=7.8Hz). Add 0.5N sodium hydroxide (11.0m4) onto the compound (529mg, 1.85mmol),
Stirred at room temperature for 2 hours. After washing the reaction solution with ethyl acetate, the aqueous layer was separated and 1NIn acid was added to make it acidic (pH 2.7).
), saturated with sodium chloride, and extracted with ethyl acetate.

The extract was washed with saturated saline and dried (sodium sulfate). When the solvent was distilled off, compound 2 (465 mg, 9
2%) was obtained as a pale yellow foam.

I R y "tcm-': 3350, 2990,
1800, 1700, 1520, max 1370. 'H NMR (CDCl23) δppm: 1.44
(9H.s), 3.00 (2H, m), 3.44 (
IH, d, J=23.4Hz), 3.67(it{,
d, J=23.4Hz). 4-64 (LH.m),
5.46 (LH, d, J-6.8Hz). Compound 2 (4
6 5mg. 1. A 4N hydrogen chloride-dioxane (6%) solution was added to 71 mmol), and the mixture was stirred at room temperature for 1 hour. The solvent was distilled off, ethyl ether was added to the residue,
Decanted (3 times). The precipitate was dried to yield Compound 3 (318 mg, 85%) as a colorless powder.

I R y KBrcm-': 3410, 2980
, 1810, 1730. 1600, max 1505. 1440. 'H-NMR (DMSO-d6) δppm: 3.05
(2H, d, J=5.8Hz). 3.87 (0.5H
,'s). 4.30 (lH.m), 5.18 (0.
5H,s). 'H-NMR (D20) δppm: 3.18 (1H,
dd, J-16.6.6.7Hz). 3.29 (LH
, dd, J-16.6.5.4Hz), 4.42(I
H, dd, J = 6.7, 5.4Hz), 4.08 (I
H,s)-SI MS(m/z)l 7 3(M+H
)” Example 2 (R)-N-{ert-butoxycarponylaspartic acid α-methyl ester (1.
60 1g, 6.0 8mmo! N,N'-carponyldiimidazole (1.26 1 g. 7.7 8 mmol) was added to a solution of ) in tetrahydrofuran (34d) and stirred for 6 hours. Magunium salt of malonic acid monomethyl ester (1.674g.6.4
8 mmol) was added thereto, and the mixture was stirred at room temperature for 18 hours. After filtering the reaction solution, water was added and extracted with ethyl acetate. The extract was washed successively with IN hydrochloric acid, water, saturated aqueous sodium bicarbonate, water, and saturated brine, and then dried (sodium sulfate). When the solvent was distilled off and subjected to silica gel column chromatography (2-5 cm x 40 cm; ethyl acetate-hexane - 1:3 → 1:2 → 1:1), (R)-2 was obtained.
- tert-butoxycarponylamino-4-oxo 1,6-hexanionic acid dimethyl ester (1.4
5 4g. 79%) was obtained as colorless prismatic crystals.

mp48-49°C Elemental analysis value C I3H 2 1 N O y calculated value
C 51.48; H 6.98; N 4.62
Actual value C 51.38; H 6.96; N
4.65I R v KBrcm-': 3390.
2960. 1740, 1720, 1520, ma
x 1440, 1410. 1390. 'H NMR (CD(,Q3)δppm: 1.45
(9H, s), 3.10 (IH, dd, J-4.4.
18.4Hz), 3.28(IH, dd, J-4.4
, 18.4Hz). 3.49 (2H, s), 3.7
4 (3H, s), 3.75 (3H, s), 4.54 (
LH, m), 5.48 (LH, m). Light intensity [σ] 14.2° (c = 0.50, methanol) in argon stream (R)-2-tart-butoxycarponylamino-4-oxo 1,6-hexanionic acid dimethyl ester (910 mg) .3. Hydroxylamine hydrochloride (Ommol) in ethanol (23d) solution
209 mg, 3.00 mmol) and sodium carbonate (159 mg, 1.50 mmol) were added, and the mixture was heated under reflux for 1 hour. Insoluble matter was filtered off, and the filtrate was concentrated. The residue was subjected to silica gel column chromatography (2
．． 5cmX40cm; Ethyl acetate-hexane-2=1→
Compound 4 (402 mg.47%) was obtained as a pale yellow foam.

I R y “tcm-”: 3360.2
990, 1800, 1740. 1710.
max 1510, 1440, 1370. ' H N M R (C D C Qs) δppm
: 1.44 (9H, s). 2.87 (LH, dd,
J=]. 5.2, 7.8t{z). 3.01 (18,
dd, J-5.15.2Hz), 3.45(IH, d
, J=23.4Hz). 3.67 (IH, d, J -23.4/Hz), 3.81 (3t{,s) 4.
59 (LH, m). 5.41 (IH, d, J=7.8
Hz). 0 to compound 4 (402mg.1.40mmol)
．． 5N NaOH (8.4WLl2) was added and stirred at room temperature for 2 hours.

After washing the reaction solution with ethyl acetate, the aqueous layer was separated, acidified (pH 2.7) with IN hydrochloric acid, saturated with sodium chloride, and extracted with ethyl acetate. The extract was washed with saturated brine and dried (sodium sulfate). When the solvent was distilled off, compound 5 (
3 6 3mg. 95%) was obtained as a pale yellow foam.

I R y "tcm"-': 3350. 2980
．． 1800. 1700, 1510, max 1370. 'H NMR (CDCL) δppm: 1.44 (9
H, s), 3.00 (2H, m). 3.45 (LH
, d, J-23.4Hz). 3.67 (IH, d, J
=23.4Hz), 4.64(IH, m), 5.4
8 (IH, d, J=7.8Hz). Compound 5 (3 6
3mg, 1.33mrnol) was added with a 4N hydrogen chloride-dioxane (6tl2) solution, and the mixture was stirred at room temperature for L hours. The solvent was distilled off, ethyl ether was added to the residue, and the mixture was decanted (3 times). The precipitate was dried to yield compound 6 (233 mg, 80%) as a colorless powder.

I R I7KB'cm-': 3320, 297
0. 'l820, 1800. 1740, max 1620. 1500, 1380. 'HNM
R(DMSO da) δppm: 3.05 (2H,
d, J=5.8Hz). 3.87 (0.5H, s).
4-30 (lH.m). 5.17 (0.5H, s)
．． 'H-NMR (D20) δppm: 3.14 (LH,
dd, J-16.5, 6.6Hz). 3.25 (IH
．． dd, J-16.5, 5.4Hz). 4.31 (L
H, dd, J=6.6.5.4Hz), 4.79(I
H. s). S IMS(m/z)l 7 3(M+H)
“Example 3 (S)-N-tert- at room temperature in an argon stream
N,N'-carponyldiimidazole (1-0 5g, 6.4 8mmol) was added to a solution of ptoxycarbonylglutamic acid a-methyl ester (1-5 3g.5.8 7mmol) in tetrahydride a7 run (3M), Stirred for 6 hours. Magnesium salt of malonic acid monomethyl ester (1.67 g.6.45 m
mol) and stirred at room temperature for 16 hours. After filtering the reaction solution, water was added and extracted with ethyl acetate. The extract was washed successively with 1N hydrochloric acid, water, saturated aqueous sodium bicarbonate, water, and saturated brine, and then dried (sodium sulfate).

The solvent was distilled off and silica gel column chromatography 7E (
2.5cmx40cm; Ethyl acetate-hexane-l: 3
→t;2-1:l) gives (S)-2-tert-
Butoxyluponylamino-5-oxo-1,7-heptaniic acid dimethyl ester (1.125 g. 60%) was obtained as a colorless oil.

IR, neatCm-1, 3390, 2990
．． 1750. 1?20. 1520, max 1440. 1370. 'H-NMR (CDCf23) δppm: 1.43 (
9H,s). 2.05 (2H, m). 2.63 (2
H, t, J=6.3Hz), 3.44 (2H, s).
3.73 (6H, s). 4.22 (IH, m).
5.15(l}I.m). In Angol airflow (S) -
2-tert-butoxyluponylamino-5-
Oxo 1,7-heptanedioic acid dimethyl ester (7
5 6mg. 2.3 8 mmol) of ethanol (2M
) solution of hydroxylamine hydrochloride (1 6 7 mg,
2-40mmo+), sodium carbonate (127m
g. 1.20 mmol) was added thereto, and the mixture was heated under reflux for 1 hour. Insoluble materials were filtered off, the filtrate was concentrated, and the residue was subjected to silica gel column chromatography (2.5cm x 40c+n
When applied to ethyl acetate-hexane = m1:2 → 2:1 → ethyl acetate → ethyl acetate-methanol - wI9; 1), compound 7 (lO 2mg. 14%) was obtained as a pale yellow foamy substance. .

I R v neaLcm-': 3390, 2990
．． 1805.174 (L 1710, maX 1520, 1450, 1370. 'H-NMR (CDCf2,) δppm: 1.43 (
9H,s). 1.90-2.70 (48, m). 3
．． 39 (lH.d, J=26.3Hz). 3-52 (
IH, d, J = 26.3Hz), 3.73 (3H, s
), 4.31 (IH, m). 5.30 (IH, d,
J-8Hz) - Compound ヱ (6 5 5 mg, 2.1 8 mmol)
．． 5N sodium hydroxide (12.8m) was added and stirred at room temperature for 2 hours. After washing the reaction solution with ethyl acetate, the aqueous layer was separated, acidified (pH 2.7) with 1N hydrochloric acid, saturated with sodium chloride, and extracted with ethyl acetate. The extract was washed with saturated brine and dried (sodium sulfate). The solvent was evaporated to give compound 8 (575 mg, 92%) as a pale yellow foam.

I R y neatcm"": 3350, 299
0, 1800, 1700, 1520, maX 1370. 'H-NMR (CD CQs) δppm: 1.
43 (9H, s), 1.90-2.80 (4H, m
). 3.43 (2H, s). 4.35 (IH, m)
．． 5.35 (LH, m). 4 to compound 8 (9 2 mg.0.3 2 1 mmol)
Add N hydrogen chloride monodioxane (6-) solution and stir at room temperature for 1
Stir for an hour. The solvent was distilled off, ethyl ether was added to the residue, and the mixture was decanted (3 times). The residue was dried to yield Compound 23 (53 mg.71%) as a colorless powder.

IRyKBrcm-': 3410. 2980.
1810. 1?30. 1600, maX 1505. 1440. 'H-NMR (DMSO-d,) δppm: 2.12
(2H, m), 2.61 (2H.m). 3.85 (0
．． 5H,s). 3.97 (IH, m). 5.08(
0.5H. s). 'H-NMR (D.O) δppm = 2.29 (2t{
, m). 2.75 (2H, dt, J-6.4, 3.0
Hz). 4.13(11{,t,J-6.4Hz).
4.81 (IH, s). SIMS (m/z) 1 7 8 (M+H)” Example 4 (R)-N-tert- at room temperature in an argon stream
A solution of butoxycarbonylglutamic acid σ-methyl ester (1-5 6g.5.9 8mmol) in tetrahydro7rane (30d) was added with N,N'-carponyldiimidazole Cl. 1 6g. 7.15 mmol) was added and stirred for 6 hours. Magnesium salt of malonic acid monomethyl ester (1.70 g; 6.58 mm
ol) was added and stirred at room temperature for 16 hours. The reaction solution is concentrated, dissolved in ethyl acetate (5072), water is added, and insoluble matter is filtered off. The filtrate was extracted with ethyl acetate, and the extract was mixed with 1N hydrochloric acid, water, saturated aqueous sodium bicarbonate, water,
After sequentially washing with saturated brine, it was dried (sodium sulfate). The solvent was distilled off and the residue was subjected to silica gel force column chromatography (2.5 cm x 4 Q cm; ethyl acetate-hexane = 1:3 → 1:2 → 1:1) to give (R) -
2-tert-butoxyluponylamino-5-
Oxo-1,7-heptanionic acid dimethyl ester (1
．． 3 0g. 68%) was obtained as a colorless oil.

IRvn8atcm-l: 3370, 298
0. 1750, 1720. 1520. maX 1440. 1370. 'H-NMR (CDC(11)δppm: 1
．． 45 (9H.s). 1.80-2.80 (4H,
m). 3.48(21{,s). 3.75 (6H,
s). 4.22 (IH, m), 5-14 (lH.m
)-In Angol air stream (R)-2-tert-butoxylponylamino-5-oxo 1.7-hebutanionic acid dimethyl ester (1.30g.4.08m
Hydroxylamine hydrochloride (284mg.4.09mmol) in ethanol (35l!l2) solution
l), sodium carbonate (2 1 6 mg.2 .0 4
mmol) and heated under reflux for 1 hour. Insoluble matter was filtered off, the filtrate was concentrated, and the residue was subjected to column chromatography using silica gel (2.5 cm x 40 cm; ethyl acetate-hexane = 1:2 → 2:l → ethyl acetate → ethyl acetate-methanol - 02 1), compound 9 (4 8
9mg. 40%) was obtained as a pale yellow foam.

l R vne"cm-'I 3370. 2980,
1800, 1750. 1710, max 1520. 1440. 1370. 'H-NMR
(CDOff.) δppm: 1.45 (9H, s).
1.902.80 (4H, m), 3.38 (IH, d
, J-26.3Hz), 3.52 (IH, d, J=2
6.3Hz). 3.73 (3H, s). 4.41 (
LH, m). 5.30 (LH, d, J-7.2Hz)
．． 0 to compound 9 (4 5 1 mg, 1.5 0 mmol)
．． Add 5N sodium hydroxide (9.0d) and stir at room temperature for 2 hours.
Stir for hours. After washing the reaction solution with ethyl acetate, the aqueous layer was separated, acidified (pH 2.7) with 1N hydrochloric acid, saturated with sodium chloride, and extracted with ethyl acetate. The extract was washed with saturated brine and dried (sodium sulfate).

When the solvent was distilled off, the compound 0 (3 7 8 mg.8 8
%) was obtained as a pale yellow foam.

I R y "tcm-'= 3350. 2990.
1800, 1700, 1520. max 1370. 'H-NMR (CD Ci23) δppm:
1.45 (9H, s). 1.90-2.70 (4H,
+n), 3.47 (2H.s), 4.41 (lH.s).
m). 5.23 (IH, d, J=6.8Hz). A 4N hydrogen chloride-dioxane (6-) solution was added to Compound 0 (350 mg. 1.22 mmol), and the mixture was stirred at room temperature for 1 hour. The solvent was distilled off, ethyl ether was added to the residue, and the mixture was decanted (3 times). The residue was dried to yield Compound 24 (291 mg.81%) as a colorless powder.

IRyKB'cm-': 3400, 2900
．． 1800, 1720. 1600, max 1490. 1440. 'H-NMR (DMS〇-aS) δppm: 2.12
(2H.m), 2.61 (2H, m), 3.85 (0
．． 51{,s), 3.94(lH,m), 5.08
(0.5H, s). 'H-NMR (D, O) δppm: 2.28 (2H,
m). 2.75 (2H, dt, J=6.4.3Hz)
．． 4. lO(IH,t,J-6.4Hz), 4.81
(LH,s). SI MS (m/z)l 3 7 (M+H)'' Example 5 (S) N-tert-ptoxylponylaspartic acid a-methyl ester (2.
70g, IO. N,N'-carponyldiimidazole (2.12g.13.09mmol) in tetrahydrofuran (60d) solution.
1) was added and stirred for 6 hours. Magnesium salt of 2-methylmalonic acid monomethyl ester (3.1
3g, l O. 9 l mmol) was added thereto, and the mixture was stirred at room temperature for 18 hours. The reaction solution was concentrated, dissolved in ethyl acetate (5M), water was added, insoluble matter was filtered, the filtrate was extracted with ethyl acetate, and the extract was mixed with IN hydrochloric acid, water, and saturated sodium bicarbonate IJ. After sequentially washing with water, water, and saturated brine, it was dried (sodium sulfate). The solvent was distilled off and column chromatography using silica gel 7E (2.5 cm x 40
cm; Ethyl acetate-hexane-l: 2-1: l-2
: When attached to l), (S) − 2 − tert
-butoxyluponylamino-5-methyl-4-oxo-1,6-hexanionic acid dimethyl ester (2.2
8g. 66%) was obtained as a colorless oil.

I R y"Lcm-': 3380, 2990.
1740, 1720. 1500. max 1440. 1390, 1360. 'H-NMR
(CDCQ3) δppm: l-35 (3H, d, J-7
Flz). 1.45 (9H, s). 3.07 (0
．． 34H, dd, J-18.2, 4.4Hz). 3.1
4 (0.66H, dd, J-12.8, 4.4Hz).
3.24 (0.66H, dd, J=lO.8.4.4
Hz), 3.29 (0.34H, dd, J-18.4
．． 4Hz). 3.55 (IH.q.J-7Hz).
3.74 (3H, s). 3.75 (3H, s). 4
．． 53 (lH.n). 5.48 (IH, br d, J
-8Hz). In argon stream (S)-2-te
rt-Poxylponylamino-5-methyl-4-oxo1,6-hexaniic acid dimethyl ester (2.
28g. Hydroxylamine hydrochloride (499mg.7.18mmol) in ethanol (50d) solution.
l 8 mmol), sodium carbonate (3 8 1 mg,
3.59 mmol) was added thereto, and the mixture was heated under reflux for 1 hour. Insoluble materials were filtered off, the filtrate was concentrated, and the residue was subjected to silica gel column chromatography (2.5 cm x 40 cm; ethyl acetate-hexane - 2:1 -> ethyl acetate -> ethyl acetate - methanol = 9:1). Compound 1 1 (9 0
1mg. 42%) was obtained as a pale yellow foam.
child.

I R y"tcm-': 3370. 2980.
1790. 1740, 1710. max 1500, 1440. 1370. 'H-NMR (CD Off,) δppm: 1.36 (
1.5H, d, J-7.2Hz), 1.45(9H,
s). 1.76 (1-5H.s), 3.59 (0.
5H, q. J=7.21{z). 3.81 (3H, s)
．． 4.59 (IH, m), 5.43 (IH, br)
．． 0.5N NaOH (18mi2) was added to the compound supernatant (901mg, 3.00mmol), and the mixture was stirred at room temperature for 2 hours.

After washing the reaction solution with ethyl acetate, the aqueous layer was separated, acidified (pH 2.7) with IN hydrochloric acid, saturated with sodium chloride, and extracted with ethyl acetate. The extract was washed with saturated brine and dried (sodium sulfate). When the solvent is distilled off, compound 2
(739 mg, 86%) was obtained as a pale yellow foam.

I R y neatcm-': 3400, 298
0, 1710. 1620. 1510, max 1390. 'H-NMR (DMSO-d6) δppm: 1.36
(9H.s), 1.65 (3H.s), 2.85 (2H.s)
, d, J = 6.5Hz). 4.19 (IH, m),
7.21 (lH.d, J-8.6Hz). Compound 1 2
A 4N hydrogen chloride-dioxane (9-) solution was added to (739mg.2.58mmol) and stirred at room temperature for 1 hour. The solvent was distilled off, ethyl chloride was added to the residue,
Decant 3 times). The precipitate was dried to yield Compound 13 (582 mg, 69%) as a colorless powder.

I R y KBram-': 3320, 2970
, 1720, 1620, 1500, max +440. 'H-NMR (DzO) δppm = 1.79 (3Ls
). 3.22 (IH, dd. J-15.4.6.6H
z). 3.31 (IH, dd. J-15.6.6.6
}1z). 4-28 (IH.t.J-6.6Hz).
SIMS (m/z) 1 87 (M+H)” Example 6 (R)-N-tert at room temperature in an argon stream
-Butoxycarbonyl aspartic acid a-methyl ester (2-4 7 2 g. l O.Ommol) in tetrahydrofuran (60 ml) was added with N,N'-carponyl diimidazole (1.9 4 6 g. 1 2.0 mm).
ol) was added and stirred for 6 hours. Magnesium salt of 2-methylmalonic acid monomethyl ester (2.8
7g, IO. Ommol) was added thereto, and the mixture was stirred at room temperature for 17 hours. The reaction solution was concentrated, dissolved in ethyl acetate (50ml), water was added, insoluble materials were filtered, and the filtrate was extracted with ethyl acetate. The extract was washed successively with IN hydrochloric acid, water, saturated aqueous sodium bicarbonate, water, and saturated brine, and then dried (sodium sulfate). When the solvent was distilled off and subjected to silica gel column chromatography (2.5 cm x 40 cm; ethyl acetate-hexane-l:2→1:l→2:1), (R)-2-tert-butoxylponylamino-5-methyl was obtained. -4-Oxo-1,6-hexanionic acid dimethyl ester (2.81 g, 89%) was obtained as a colorless oil.

I R y neatam-': 3380. 298
0. 1750, 1720. 1500, max 1450, 1390. 1360. ' H - N M R (C D C I23) δp
pm: 1.35 (3H, d, J-7.2Hz), 1
．． 44 (9H, s). 3.07 (0.34H, dd,
J=18.2.4.4Hz). 3.15 (0.66H
, dd, J=13.4.4Hz). 3.24 (0.6
6H, dd, J=lO. 6.4.4Hz). 3.29
(0.34H.dd, J-18.4.4Hz). 3-
55 (IH, q, J=7.2Hz). 3.74 (6H
, s). 4.54(l}l.m), 5.49(IH
, br d, J-8Hz). In argon flow (R) -
Hydroxylamine hydrochloride (511 mg) was added to a solution of 2-tart-ptoxycarbonylamino-5-methyl-4-oxo1,6-hexanionic acid dimethyl ester (2.33 g.7.35 mmol) in ethanol (50 tl2). .7.35 mmol) and sodium carbonate (390 mg.3.68 mmol) were added, and the mixture was heated under reflux for 1 hour. Insoluble matter was filtered off, the filtrate was concentrated, and the residue was subjected to silica gel column chromatography (2
．． 5cmX40cm; Ethyl acetate-hexane-2=
Compound-14 (1.12 g.5 1%) was obtained as a pale yellow foam.

I R v neatam””: 3370. 298
0. 1750. 1720. 1500. maX 1450. 1430. 'H NMR (CDCL) δppm: 1.38 (1
．． 5H, d, J-7Hz). 1.45 (9H, s).
1.78 (1.5H, s). 3.59 (0.5H.
q. J=7Hz). 3.81 (3H, s). 4.6
1 (IH, m). 5.42 (IH, br). 0.5N NaOH (16mff) was added to Compound 4 (819mg.2.73mmol) and stirred at room temperature for 2 hours.

After washing the reaction solution with ethyl acetate, the aqueous layer was separated and INm
The mixture was made acidic (pH 2.7) and saturated with sodium chloride, and then extracted with ethyl acetate. The extract was washed with saturated brine and dried (sodium sulfate). When the solvent is distilled off, compound 1
5 (490 mg.63%) was obtained as a pale yellow foam.

I R y "tcm-': 3370, 3250.
2980. 1710, 1620. max 1510, 1390. 'H-NMR (DMSO ds)
δppm: 1.36 (9H.s), 1.65 (3H.s)
s), 2.85 (2H, d.J = 6.5Hz), 4
．． 19 (IH, m). 7.22 (IH, d, J-8.6
Hz). Compound 5 (300mg. 1.05m
A 4N hydrogen chloride monodioxane (4-) solution was added to the mixture and stirred at room temperature for 1 hour. The solvent was distilled off, ethyl ether was added to the residue, and the mixture was decanted (3 times).
. When the precipitate is dried, the target compound 16 (250
mg, 72%) was obtained as a colorless powder.

I R y KB'cm-' 2 3450.
2980. 1720, 1640. 15
00. max 1380. 'H-NMR(D20)δppm
: 1.79 (3H, s), 3.23 (IH, dd,
J= 15.4.6.6Hz), 3.32(IH, d
d, J= 15.4.6.6Hz), 4.35(LH
, t, J=6.6Hz). S IMS (m/z) 1 8
7(M+H)” Example 7 (S)-N-tert at room temperature in an argon stream
-N,N'-carbonyldiimidazole (1-68 g. 10.36 mmol) was added to a solution of -butoxycarbonylglutamic acid a-methyl ester (2.26 g. 8.6 5 mmol) in tetrahydrofuran (50 ml2) and stirred for 6 hours. . Magnesium salt of 2-methylmalonic acid monomethyl ester (2.7 2 g, 8
．． 65++oyol) was added and stirred at room temperature for 18 hours. The reaction solution was concentrated, dissolved in ethyl acetate (50 ml), water was added, and insoluble matter was removed by filtration. The filtrate was extracted with ethyl acetate, and the extract was washed sequentially with IN hydrochloric acid, water, saturated aqueous sodium bicarbonate, water, and saturated brine, and then dried (i.
sodium chloride). The solvent was distilled off, and the residue was subjected to silica gel column chromatography (2.5 cm x 3 Q cm;
When added to ethyl acetate-hexane (l:2→1:l), (
S)-'2-tart-butoxylponylamino-6-methyl-5-oxo1.7-hebutanedioic acid
l-Methyl 7-ethyl ester (1.03g, 34%
) was obtained as a colorless oil.

I R v "tcm-': 3380. 2990,
1750. 1710. 1510. max 1445. 1360. 'H-NMR (CDCQ3) δppm: 1.27 (3H
,t,. 1;-7Hz), 1.34(3H,d,J-
7.2Hz). 1.44 (9H, s). 1.80-
2.90 (4H, m). 3.52 (lH.q.J-7
．． 2Hz). 3.75 (3H, s), 4.27 (LH
．． m). 5.11 (LH.m). In an argon stream (S
) -2-tart-butoxyluponylamino-6-methyl-5-oxo1.7-heptanionic acid
1-Methyl 7-ethyl ester (1.95g, 5.
Hydroxylamine hydrochloride (391mg.5.63mmol) in ethanol (39tf2) solution
l), sodium carbonate (298mg.2-81m
mol) and heated under reflux for 1 hour. Insoluble materials were filtered off, the filtrate was concentrated, and the residue was subjected to column chromatography using silica gel (2.5 cm x 40 cm; ethyl acetate-hexane-1:2→2:1-vinegar [ethyl→ethyl acetate-methanol-9). ;l), compound 1 7(
4 2 3mg. 24%) was obtained as a pale yellow foam.

IRuneaLcm-': 3380, 299
0. 1740. 1710. 1685, max 1510. 1440. 1380. 'H-NMR (CD (1.) δppm: 1.45 (9
H,s), 1.81 (3H.s). 1.80-2.
80 (4H.m). 3.78'(3H,s), 4.
21 (lH.T!). 5.30 (LH, d, J-7.
4Hz). Compound 17 (320mg, 1.0
0.5N sodium hydroxide (5.7d
) and stirred at room temperature for 2 hours. After washing the reaction solution with ethyl acetate, the aqueous layer was separated and acidified with 1N hydrochloric acid (pH 2.
7), saturated with sodium chloride, and then extracted with ethyl acetate.

The extract was washed with saturated saline and dried (sodium sulfate). When the solvent was distilled off, compound 1 8 (3 0 0
mg. 98%) was obtained as a pale yellow foam.

I R y neatc+n-': 3400, 29
80. 1725, 1690, 1520, max 1370. 'H NMR (CDCL) δppm: 1.46 (
9H,s), 1.79(3H,s), 1.90
-2.70 (4H, m), 4.25 (IH, m).
5.54 (IH, d.J-7.2Hz). Compound 18 (300mg, 1.0mmol)
A 4N hydrogen chloride monodioxane (6-) solution was added to the mixture, and the mixture was stirred at room temperature for 1 hour. The solvent was distilled off, ethyl ether was added to the residue, and the mixture was decanted (3 times). When the precipitate was dried, compound 9 (278mg.81%)
was obtained as a colorless powder.

I R y KBram-': 3350. 2900
, 1745. 1630. 1560. max 1500, 1210. 'H NMR (D20) δppm: 1.77 (3H
, s). 2.26 (2B, m). 2.81 (2H,
m), 4.08 (IH, m). S IMS (m/z)
20 1(M+H)” Example 8 (R)-N-tert-butoxycarbonylglutamic acid σ-methyl ester (
2.26g, 8.65mmol) in tetrahydrofuran (50ml2) was added N,N'-carbonyldiimidazole (1.68g, 10.36mmol).
) and stirred for 6 hours. Magnesium salt of 2-methylmalonic acid monomethyl ester (2.9 9
g. 9.50 mmol) was added thereto, and the mixture was stirred at room temperature for 18 hours. The reaction solution was concentrated, dissolved in ethyl acetate (50 ml), water was added, and insoluble matter was removed by filtration. The filtrate was extracted with ethyl acetate, and the extract was washed sequentially with IN hydrochloric acid, water, saturated sodium bicarbonate, water, and saturated brine, and then dried (
sodium sulfate). The solvent was distilled off, and the residue was subjected to silica gel column chromatography (2.5 cm x 40
cm; ethyl acetate-hexane-1:2→1:l-)
When subjected to
63%) was obtained as a colorless oil.

rR y0eatcm-': 3370. 2980
．． 1740, 1710. 1510, maX 1445. 1360. 'H-NMR (CDCQs) δppm: 1.27 (3H
, t. J-7Hz). 1.34 (38, d, J-7.
2Hz), 1.44 (9H.s). 1.80-2.
80 (4H, m). 3.52 (lH.q.J-7.2
Hz). 3.74 (3B, s). 4.25 (IH.m
). 5.10 (IH.I++). In an argon stream (R
)-2-tart-butoxycarbonylamino-
6-Methyl-5-1xo1.7-heptanionic acid l-
Methyl 7-ethyl ester (1.7 4g, 5.0
Hydroxylamine hydrochloride (350 mg.5.0 4 mmol) in ethanol (40 mg) solution.
), sodium carbonate (2 6 7 mg. 2.5 2 mm
ol) was added thereto, and the mixture was heated under reflux for 1 hour. Filter out insoluble matter,
The filtrate was concentrated, and the residue was subjected to column chromatography using silica gel (2.5 cm x 40 cm; ethyl acetate-hexane-J:2 2:l → ethyl acetate → ethyl acetate-methanol-9:l). and compound 1dan (4 7 4
mg, 30%) was obtained as a pale yellow foam.

I R y 0eatcN': 3380,2990+
1740, 1710, 1685, max 1510. 1440. 1360. ' H - N M R (C D C Qs) δpp
m: 1.46 (9H.s). 1.81(3H,s
). 1.80-2.80 (4H, m). 3.78 (
3H,s). 4.16 (LH, m). 5.42 (I
H, d, J-7.8Hz). Compound Shudan (4 70m
0.5N sodium hydroxide (9.0tg) was added to the solution (1.50mmol), and the mixture was stirred at room temperature for 2 hours. After washing the reaction solution with ethyl acetate, the aqueous layer was separated, acidified (pH 2.7) with IN hydrochloric acid, saturated with sodium chloride, and extracted with ethyl acetate. The extract was washed with saturated brine and dried (sodium sulfate). When the solvent is distilled off, compound i±(3
6 3mg. 81%) was obtained as a pale yellow foam.

I R y "tcn+-': 3300, 2970
, 1720. 1680. 1600. max 1510. 1440. 1370. 'H-NMR (CDC72s) δppm: 1.46 (
9H,s). 1.79 (3H, s). 1.80-2
．． 870 (4H, m). 4.25 (IH, m). 5
．． 52 (LH, d, J-7.6}1z). Compound main ±(3 6 3 mg. 1 .2 1 mmol
) was added with a 4N hydrogen chloride-dioxane (6all) solution, and the mixture was stirred at room temperature for 1 hour. The solvent was distilled off, and ethyl chloride was added to the residue, followed by decantation (3 times). When the precipitate is dried, compound 2 2 (3 5 5 mg.8
8%) was obtained as a colorless powder.

IR y KBrcm-': 3420. 2940
, 1720.1640. 1560, max 1500, 1250. 'H-NMR (D20) δppm: 1.77 (3H,
s), 2.26 (2H, Il1). 2.81 (2H
, m). 4.08 (1B, m). S [MS(m/z
)201(M+H)" The affinity of Test Example Compound (1) for glutamate receptors in the brain was investigated by the following method.

[Method] As mentioned above, receptors for excitatory amino-a (especially glutamate) in the brain are classified into three types: NMDA type, Quisqualate type, and Kainate type.

3H-CPP [3
− (2 = carboxypiperazin −
4-yl)propyl-1-phosph
'H-AMPA (DL-a - a
ynino-3-hydroxy-5-
Methylisoxazole-4-prop
ionic acid), and 3H-monokainate was used as the ligand for the receptor type receptor.

Crude synabular membrane specimens prepared from rat forebrain were washed four times with 50mM Tris-HCl buffer (pH 7.1).
Store frozen at -20°C until use.

On the day of the receptor binding experiment, thaw the frozen crude synabs membrane preparation and add 50mM}! The cells were suspended in JS hydrochloric acid buffer (pH 7.1) and incubated for 30 minutes at a constant temperature of 37°C. After incubation, centrifugation (48.
0 0 0
It was washed three times with Tris-HCl buffer and used for receptor binding experiments.

For NMDA receptor binding experiments, synaptic membrane preparations were treated with 10 nM sH-C in the presence and absence of the test compound.
50mM Tris-HCl buffer (pH 7.1, O
0C) for 15 minutes. Thereafter, the pellet containing the synaptic membrane obtained by centrifugation (18,000×g.IO minutes) was washed with 50 mM Tris-HCl buffer (pH 7.1), and 0.5-protosol ,New EnglandNu
(manufactured by C.Fear). When examining kissing force rates and binding to kainate receptors, synabular membrane preparations were treated with 5n in the presence or absence of the test compound.
50mM Tris-HCl buffer (pH 7.1) with M3H-AMPA (kiss force rate receptor) or 3H-Kainic acid (kainate receptor).
, O'C) for 90 minutes.

Afterwards, the incubation solution was mixed with Whatman (Wha)
Suction filtration was performed using a GF/B filter (manufactured by Whatman Corporation), the filter was washed three times with 50+nM Tris-HCl buffer (pH 7.1), and the radioactivity on the filter was measured by a conventional method. Binding to other than the receptor, i.e., non-specific binding, is the amount of binding in the presence of excess non-radioactive sodium L-glutamate (lmM), and the amount of specific binding is determined by subtracting the amount of non-specific binding from the total amount of binding. t;.

The 50% inhibitory concentration (I C.) of the test compound is 3H-C.
PP, 'H-AMPA, or "H-Kain"
It was determined as the concentration that inhibits the specific receptor binding of ic acid by 50%.

Table 2 shows the affinity of monosodium L-glutamate (hereinafter sometimes abbreviated as Glu-Na), a typical excitatory amino acid, and the compound for the above three subtype receptors. As is clear from Table 2, Gl
u-Na shows high affinity for three subtype receptors, and its IC. Values were 0.11-0.98 μM.

Compounds 1, Jodan, and 23 have affinity for kiss force rate type receptors (see margin below)

Claims (2)

[Claims] (1) Formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the formula, R^1 is hydrogen or a lower alkyl group, R^2
represents an optionally protected amino group, COR^3 represents an optionally esterified carboxyl group, and n is 0 to 3.
Indicate each integer. ] A brain function improving agent containing a compound represented by or a salt thereof. (2) Formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the formula, R^1 is hydrogen or a lower alkyl group, R^2
represents an optionally protected amino group, COR^3 represents an optionally esterified carboxyl group, and n is 0 to 3.
Indicate each integer. However, compounds in which n is 2, R^1 is hydrogen, R^2 is NH_2, and COR^3 is a carboxyl group are excluded. ] or its salt.