JP2779855B2 - Compound KS-505 and method for producing the same - Google Patents

Description

The present invention relates to a novel compound having a biological activity of microbial origin,
Pharmaceutically acceptable salts thereof, methods for their preparation, and
It relates to pharmaceutical compositions containing these.

2. Description of the Related Art It is well known that various microorganisms belonging to the genus Streptomyces, for example, have various valuable bioactive substance-producing abilities, but substances exhibiting a brain function improving action derived from microorganisms belonging to the genus Streptomyces are still unknown. unknown.

Problems to be Solved by the Invention The present invention is based on the finding that certain microorganisms discovered by the present inventors can produce a novel substance having a cerebral function improving action.

An object of the present invention is to provide a novel substance of microbial origin having a cerebral function improving action, a pharmaceutically acceptable salt thereof, a production method thereof, and a pharmaceutical composition containing the same.

Means for Solving the Problems The present invention provides a compound represented by the following formula (I) and a pharmaceutically acceptable salt thereof. Hereinafter, this compound is referred to as KS-505.

KS-505 is a novel compound and has a physiological activity, for example, an anti-amnesic effect. Therefore, KS-505 is used as an effective brain function improving agent for treating and preventing cerebral dysfunction such as amnesia and dementia. There is expected.

Next, the present invention belongs to the genus Streptomyces,
A microorganism having the ability to produce KS-505 or a mutant strain having the ability to produce KS-505 is cultured in a medium, the desired compound is accumulated in the culture, and the compound is collected from the culture. A method for producing compound KS-505 is provided.

Further, the present invention provides a pharmaceutical composition having an effect of improving brain function, comprising an effective amount of compound KS-505 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or excipient. I will provide a.

 Hereinafter, the present invention will be described in detail.

I) Physicochemical properties of KS-505 Properties: White powder, acidic substance F _AB Mass spectrum: m / z 1075 (M + H-H ₂ O) ⁺ [* 1] and 1115 (M + Na) ⁺ [* 2] High resolution F _AB mass spectrum: m / z1115.5903 [* 2] C 61 H 88 O 17 calcd 1115.5920 measured without added [Note * 1 ... salt as Na.

* 2: Measured by adding salt in the usual manner. Molecular formula: C ₆₁ H ₈₈ O ₁₇ ¹ H NMR spectrum: (400 MHz, 10 mg / 0.4 ml, CD ₃ OD solution) δ (ppm): 0.77 (s), 0.80 (br s), 1.05 (d),
1.10 (s), 1.37 (s), 1.52 (m), 1.83 (m), 2.31
(M), 2.45 (m), 2.79 (br t), 2.94 (dd), 3.34
(S), 3.52 (s), 3.61 (br s), 3.72 (m), 3.81
(D), 3.90 (d), 4.36 (d), 7.16 (d), 7.29 (d) ¹³ C NMR spectrum: (100 MHz, 10 mg / 0.4 ml, CD ₃ OD solution) δ (ppm); 11.4 (q) , 15.0 (q), 16.3 (q), 17.
4 (q), 18.2 (t), 18.7 (q), 18.9 (t), 20.2
(T), 20.9 (t), 22.0 (t), 22.6 (t), 23.0
(Q), 23.1 (q), 24.5 (q), 29.6 (t), 34.1
(T), 35.4 (t), 36.7 (t), 38.4 (t), 39.5
(S), 39.7 (t), 39.8 (s), 40.5 (s), 42.8
(S), 43.1 (s), 43.3 (d), 43.4 (t), 44.1
(T), 44.2 (s), 44.4 (d), 45.1 (t), 50.5
(S), 52.3 (q), 53.9 (d), 59.1 (d), 60.3
(T), 61.2 (q), 62.7 (d), 63.2 (t), 64.1
(D), 64.3 (d), 65.1 (d), 65.7 (d), 73.2
(D), 76.7 (d), 77.0 (d), 81.1 (s), 84.7
(D), 88.2 (d), 107.3 (d), 107.6 (s) and 108.0
(S), 122.0 (d), 123.5 (s), 125.4 (d), 126.0
(S), 142.6 (s) and 142.8 (s), 156.1 (s), 170.
2 (s), 172.4 (s), 174.9 (s), 177.7 (s) Infrared absorption spectrum: (KBr method) 3450, 2950, 1730, 1715, 1460, 1385, 1270, 1240, 1120, 1
045 cm ^-1 UV absorption spectrum: (λmax, methanol solution) 221 nm (log ε = 4.47), 308 nm (log ε = 3.36) Optical rotation: ▲ [α] ²⁵ _D ▼ = -63.5 ゜ (c0.1, methanol, (Measured immediately after dissolution) Melting point: gradually changes to brown, but does not show a clear melting point.

Color reaction: Positive for each color reaction with anisaldehyde, sulfuric acid, iodine, bromocresol green, each color reaction with ninhydrin, dinitrophenylhydrazine, ferric chloride, aniline / phthalic acid, and Leydan-Smith reaction, dragen Negative Dorf reaction.

Solubility in solvents Soluble in methanol, dimethyl sulfoxide, ethyl acetate, basic water, poorly soluble in hexane, chloroform, acidic water.

KS-505 has a γ-hydroxy-γ-lactone type structure, and can have a chemically equivalent structure represented by the formula (II). In the solution, the two maintain an equilibrium relationship, but the mixing ratio varies depending on, for example, the acidity of the solvent.

In the following, when formula (I) is cited, formula (II) and a mixture of formula (I) and formula (II) shall be cited.

II) Salts of KS-505 KS-505 can be reacted with various organic or inorganic bases by known methods to obtain pharmaceutically acceptable salts. Examples of practical organic bases used for this purpose are methylamine, ethylamine, primary amines such as aniline,
Secondary amines such as dimethylamine, diethylamine, pyrrolidine, piperidine, morpholine and piperazine; and tertiary amines such as trimethylamine, triethylamine, N, N-dimethylaniline and pyridine. Examples of practical inorganic bases are alkali metals such as sodium and potassium, and alkaline earth metals such as magnesium and calcium.

 It should be noted that the method for producing this type of salt is well known.

For example, the structure of the sodium salt of KS-505 has the following formula (I
II).

The physicochemical properties of this sodium salt are as follows.

Properties: white powder, neutral substance.

Mass spectrum (SIMS): m / z1115 ( C 61 H 88 O 17 Na) + Molecular _{formula: C 61 H 85 O 17 Na} 3 1 H NMR spectrum: (400MHz, 7mg / 0.4ml, CD 3 OD solution) [delta] (ppm ); 0.78 (s), 0.81 (br s), 0.97 (d),
1.09 (s), 1039 (s), 1.52 (m), 1.88 (m), 2.27
(M), 2.48 (m), 2.72 (m), 2.94 (t), 3.35
(S), 3.53 (s), 3.64 (s), 3.73 (m), 3.80
(D), 3.92 (d), 4.40 (d), 7.05 (d), 7.43 (d) ¹³ C NMR spectrum: (100 MHz, 20 mg / 0.4 ml, D ₂ O solution) δ (ppm), 11.3 (q) , 14.8 (q), 15.9 (q), 17.
1 (q), 17.6 (t), 17.7 (t), 18.4 (q), 20.0
(T), 20.7 (t), 21,2 (t), 21.8 (t), 22.9 (q)
× 2, 24.9 (q), 29.3 (t), 32.7 (t), 33.4 (t), 3
4.8 (t), 36.0 (t), 36.3 (t), 37.8 (s), 38.8
(S), 39.1 (s), 39.2 (t), 42.1 (s) x 2,42.3
(T), 42.5 (s), 43.2 (d), 43.9 (d), 44.6
(T), 51.0 (s), 53.2 (q), 53.4 (d), 59.0
(D), 59.2 (t), 61.2 (q), 62.5 (d), 63.2
(D), 63.2 (t), 63.7 (d), 65.1 (d), 65.2
(D), 73.1 (d), 76.1 (d), 77.1 (d), 81.1
(S), 83.5 (d), 90.4 (d), 105.9 (d), 116.5
(D), 119.6 (s), 125.6 (s), 130.0 (d), 144.1
(S), 157.3 (s), 176.1 (s), 177.2 (s) x 2,182.
4 (s), 201.6 (s) Infrared absorption spectrum: (KBr method) 3430,2920,1715,1600,1570,1435,1380,1240,1040cm
^-1 UV absorption spectrum: (λmax, methanol solution) 216 nm (1 og ε = 4.15), 280 nm (1 og ε = 4.01) Melting point: gradually changes to brown, but does not show a clear melting point.

Solubility in solvent: soluble in water, methanol and dimethyl sulfoxide.

 The above data was measured with the following equipment.

NMR spectrum: Bruker (West Germany) AM-400 Mass spectrum: JEOL JMS-HX110 Hitachi M-80-B Infrared absorption spectrum: Shimadzu IR-27G Ultraviolet absorption spectrum: Hitachi 200-20 double Beam spectrophotometer Optical rotation: PerkinElmer (USA) model 141 Melting point: Yanagimoto Seisakusho Micro melting point apparatus Next, the Rf values of KS-505 thin-layer chromatography using various developing agents are shown in Table 1. Detection was performed by irradiation with ultraviolet light at 254 nm.

Development: room temperature, rising method. Deployment time: 15-40 minutes.

Acute toxicity of KS-505: Oral administration of sodium salt to ddy male mice (100
0 mg / kg). Intraperitoneal For administration LD ₅₀ =
It was 417.5 mg / kg.

III) Production method of KS-505.

KS-505 belongs to the genus Streptomyces, and cultivates a microorganism capable of producing KS-505 in a medium.
Is produced by accumulating and collecting these from the culture.

As the KS-505-producing microorganism, any microorganism may be used as long as it belongs to the genus Streptomyces and has a KS-505-producing ability. Streptomyces argenteol (Streptomyces argenteol) newly isolated from soil
us) A-2 strain (hereinafter referred to as A-2 strain).

 The bacteriological properties of the A-2 strain are as follows.

(1) Morphological characteristics The A-2 strain shows normal or vigorous growth on commonly used synthetic and natural media, and forms gray aerial hyphae. The base mycelium generally shows a pale yellow color, and no division of the hypha is observed.

The spores are formed in a simple branched spore stem from aerial hyphae in the form of ten or more long chains, and the form is spiral. The size of the mature spores is 0.7-0.9 μm × 1.0-1.1 μm, shows an oval or spherical shape, and its surface is smooth and without flagella. No sporangia is found.

(2) Growth state in various media Table 2 shows the growth state when cultured in various media at 28 ° C for 2 weeks. The color display is based on the Color Harmony Manual, Container Co.
rporation of America) According to the color classification by the 4th edition (1958, Chicago, USA), the color code is shown in parentheses after the color name.

(3) Physiological properties (a) Optimal growth temperature: 28 ° C to 35 ° C (b) Liquefaction of gelatin: no (c) Hydrolysis of starch: yes (d) Coagulation or peptonization of skim milk: no (e ) Melanoid pigment formation: None (f) Assimilation utilization of carbon source: Utilizes D-xylose, D-glucose, D-fructose, sucrose, L-rhamnose and D-mannitol. Does not utilize L-arabinose, i-insitol and raffinose.

The medium used was Pridham-Godlieb inorganic medium (ISP9).

(G) Decomposition of fibrin: none (h) Strain-optimal pH: 6.5-7.8 (i) Production of tyrosinase: none (4) Cell wall composition In the analysis of diaminopimelic acid by whole cell hydrolysis, only LL-diaminopimelic acid was found. was detected.

The mycelium is classified into the genus Streptomyces based on the spore chain formed on the aerial mycelium and the stereotype of diaminepimelic acid.

Next, the gray aerial mycelium, spiral spore chain, smooth spore surface, not producing melanin-like pigment, not producing soluble pigment or producing light yellow soluble pigment, which are characteristic of this strain, Considering the assimilation of resources,
Various known strains approved by the American Society of Bacteriology [International Journal.
Of Systematic Bacteriology (Int.J.Sy
st.Bacteriol.) 30 , 225 (1980)]. As a result, Streptomyces argenteolus can be mentioned as a closely related strain. This is in good agreement with the present strain except that Streptomyces argenteols assimilates L-arabinose and does not assimilate sucrose. As a result, this strain was named Streptomyces argenteolus A-2.

This strain was established on September 21, 1988 by the Institute of Microbial Industry and Technology, National Institute of Advanced Industrial Science and Technology, Japan, No. 2065 (FERM BP-206).
5) has been deposited.

For culturing the microorganism used for the purpose of the present invention, a usual culturing method for a microorganism belonging to the genus Streptomyces can be used. As the medium, a natural medium or a synthetic medium containing a carbon source, a nitrogen source, an inorganic substance, and the like which can be assimilated by microorganisms can be used.

Examples of carbon sources include glucose, fructose, sucrose, lactose, starch, dextrin, mannose,
Maltose, molasses, carbohydrates such as mashed potato, citric acid, acetic acid, organic acids such as fumaric acid, alcohols such as methanol and ethanol, methane, ethane, hydrocarbons such as n-propane, amino acids such as glutamic acid or glycerol, Used alone or in combination with cottonseed oil and the like. Examples of the nitrogen source include ammonium salts such as ammonium chloride, ammonium sulfate, ammonium nitrate, and ammonium phosphate; amino acids such as aspartic acid, glutamine, cystine, and alanine;
Urea, malt extract, peptone, meat extract, yeast extract,
Dried yeast, corn steep liquor, soybean flour, cottonseed meal, soybean casein, casamino acid, Pharmamedia (Procter & Gamble, USA), Soluble
It is used alone or in combination with vegetable protein, vegetable and fruit juices, etc.

Examples of inorganic substances are potassium dihydrogen phosphate, disodium hydrogen phosphate, magnesium phosphate, magnesium sulfate,
Ferrous sulfate, manganese sulfate, cobalt sulfate, zinc sulfate,
It is used alone or in combination with ammonium molybdate, aluminum potassium sulfate, barium carbonate, calcium carbonate, cobalt chloride, magnesium chloride, potassium chloride, sodium chloride and the like.

If necessary, substances that promote or stabilize the growth of microorganisms, such as vitamins such as pantothenic acid or buffers such as 3- (N-morpholino) propanesulfonic acid, may be added to the medium.

If the microorganism requires certain substances for growth, it can add what is needed for growth.

The shaking culture method, particularly the aeration stirring culture method, is most suitable for the culture. The culturing temperature is 20 to 40 ° C, and most preferably 25 to 30 ° C. The pH of the medium is preferably about 6-8. When culturing is usually performed in liquid culture for 3 to 10 days, KS-505 accumulates in the culture solution and in the cells.

The isolation and purification of KS-505 from the culture after completion of the culture can be performed by a conventional method. Practical examples include extraction of cell components with solvents such as acetone and methanol, filtration, removal of cells by centrifugation, etc., distribution with an appropriate solvent system, adsorption resin, silica gel, modified silica gel, alumina, cellulose, diatomaceous earth, KS-505 can be isolated by column chromatography or thin-layer chromatography using magnesium silicate, gel filtration agent and the like.

A practical example of the isolation and purification of KS-505 from a culture is as follows.

The cells are removed by filtering or centrifuging the culture. The obtained filtrate or supernatant is passed through an adsorption resin, for example, Diaion HP-20 (manufactured by Mitsubishi Kasei) to adsorb the active substance. The eluate is then eluted with a suitable solvent such as methanol and the eluate is concentrated under reduced pressure. This concentrate is dissolved in a suitable solvent, for example, a mixed solvent of chloroform / methanol / ethanol / water (10: 4: 4: 1; volume ratio), and silica gel chromatography is performed using a mixed solvent having the same composition. If necessary, silica gel chromatography is repeated using a solvent system of the same or a different composition. After the fractions containing KS-505 are collected and concentrated under reduced pressure, KS-505 is extracted using a suitable water-immiscible solvent (eg, ethyl acetate) under acidic conditions. After concentrating the extract, the same silica gel chromatography as described above is repeated. The obtained crude KS-505 is dissolved in an acidic solvent such as a mixed solvent of methanol / water / acetic acid, and then subjected to preparative high performance liquid chromatography using a methanol / ammonium acetate buffer (7: 3 volume ratio). KS
-505 white powder is obtained. In addition, KS-5 in the above purification step
05 can be detected by performing thin layer chromatography using a silica gel plate containing a fluorescent agent and then irradiating with ultraviolet light at 254 nm.

IV) Pharmaceutical Composition The pharmaceutical composition according to the present invention comprises an effective amount of the compound KS-50
5 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or excipient. The present composition has an anti-amnestic effect as shown in the following test examples, and is expected to be effective for treatment and prevention of cerebral dysfunction such as amnesia and dementia.

The dose of the composition depends on the intended therapeutic effect, the method of administration,
It depends on the duration of treatment, age, weight, etc., but usually per adult / day by oral or parenteral (eg, injection, infusion, rectal administration by suppository, skin patch)
It is 0.01 to 100 mg / kg as KS-505. For administration, KS-5
05 can be used as it is, but generally, tablets,
Used as pills, powders, granules, capsules, suppositories, injections, and drops. The preparation of these drugs is well known.

The drug may contain, for example, various excipients, lubricants, binders, disintegrants, suspending agents, isotonic agents, emulsifiers, absorption promoters, and the like.

Examples of carriers used in pharmaceutical compositions are water, distilled water for injection, saline, glucose, fructose, sucrose, mannitol, lactose, starch, corn starch, cellulose, methylcellulose, carboxymethylcellulose, hydroxypropylcellulose. , Alginic acid, talc, sodium citrate, calcium carbonate, calcium hydrogen phosphate, magnesium stearate, urea, silicone resin, sorbitan fatty acid ester, glycerin fatty acid ester and the like.

The medicament can contain KS-505, for example, from 0.01 to 85% by weight.

The following examples and test examples illustrate the invention.

Example 1 Streptomyces argenteorus (St.
reptomyces argenteolus) A-2 (FERM-BP-2065) strain is used. As a seed medium, glucose 1.0 g / dl, soluble starch 1.0 g / dl, meat extract (Kyokuto Pharmaceutical Co., Ltd.) 0.3 g / dl,
A medium (pH 7.2) having a composition of 0.5 gmdl of yeast extract (manufactured by Daigo Kunitachi Chemical Co., Ltd.), 0.5 g / dl of peptone (manufactured by Difco), and 0.2 g / dl of calcium carbonate was used.

Inoculate the strain into a test tube containing 10 ml of seed medium,
Shaking culture was performed for a day. 4 ml of this culture solution was used as a seed medium 4
Inoculate 300 ml Erlenmeyer flask containing 0 ml
Shaking culture was performed for a day. Further, 40 ml of this culture was inoculated into 360 ml of a seed medium having the above composition, and cultured with shaking at 28 ° C. for 2 days. The seed culture solution 1.8 thus obtained was used for the fermentation medium 18 having the following composition.
Was inoculated into a 30 jar fermenter.

Composition of fermentation medium: glucose 0.5 g / dl, maltose 4.0 g / dl, 3- (N-
Morpholino) propanesulfonic acid 1.0 g / dl, magnesium sulfate heptahydrate 0.05 g / dl, soybean powder 1.5 g / dl, Pharmamedia (Procter & Gamble, USA) 1.5 g
/ dl, calcium carbonate 0.5g / dl (pH 7.0).

The culture was performed at 28 ° C. for 5 days under aeration and agitation (aeration amount: 1).
8 / min, rotation speed: 300 rpm).

After completion of the culture, the supernatant obtained by centrifugation (7000 rpm) of the culture solution was passed through a column 2 filled with adsorption resin Diaion HP-20 (manufactured by Mitsubishi Kasei Co., Ltd.),
After washing with 50% methanol and 10 methanol successively, elution was carried out with 10 methanol containing 1% ammonia. The methanol fraction containing 1% ammonia is collected and concentrated under reduced pressure to give a brown oil of about 2.7 gs. This brown oil was dissolved in 10 ml of a mixed solvent of chloroform / methanol / ethanol / water (10: 4: 4: 1) and filled with 500 ml of silica gel (Wakogel C-200, Wako Pure Chemical Industries, Ltd.) filled with a mixed solvent of the same composition. (Manufactured by Kogyo Co., Ltd.), supplied to the top of the column, developed using 1500 ml of a mixed solvent of the same composition, and then developed using 1000 ml of methanol.

The obtained liquid was collected and concentrated under reduced pressure to obtain 1.5 g of a brown oily substance. This brown oil was dissolved in 4 ml of a mixed solvent of chloroform / methanol / ethanol / water (10: 4: 4: 1) and filled with a mixed solvent of the same composition.
The mixture was supplied to the upper end of a 0 ml silica gel (Wakogel C-200, manufactured by Wako Pure Chemical Industries, Ltd.) column and developed using a mixed solvent having the same composition. The eluate was collected in 10 ml portions, and from the active fraction 17
No. 42 was collected and concentrated under reduced pressure to give about 460 mg of a brown oil. The brown oil was suspended in about 50 ml of 10% methanol, adjusted to pH 2 with 2N hydrochloric acid, and extracted three times with 400 ml each of ethyl acetate. The ethyl acetate layers were collected and concentrated to dryness under reduced pressure to obtain 266 mg of a brown solid.

This brown solid was dissolved in 1 ml of a mixed solvent of chloroform / methanol / ethanol / water (10: 4: 4: 1), and then filled with 50 ml of silica gel (Wakogel C-300, Wako Pure Chemical Industries, Ltd.) filled with a mixed solvent of the same composition. (Manufactured by Kogyo Co., Ltd.) and supplied to the upper end of a column and developed using a mixed solvent having the same composition. 5m eluate
Fractions 13 to 25 containing KS-505 were collected and concentrated under reduced pressure to obtain about 256 mg of a light brown solid. After dissolving this light brown solid in 1 ml of a mixed solvent of chloroform / methanol / ethanol / water (10: 4: 4: 1), a row bar column (Lichroprep Si60; size B) equilibrated with a mixed solvent of the same composition , Merck).

The mixture was developed with 1000 ml of a mixed solvent of the same composition, and then developed with 900 ml of a mixed solvent of chloroform / methanol / ethanol / water (10: 4: 4: 2). 10 ml of eluate eluted with a mixed solvent of chloroform / methanol / ethanol / water
Fractions 14 to 34 containing KS-505 were collected and concentrated to dryness to obtain 56 mg of a pale yellow powder.

28 ml of a mixture of methanol / water / acetic acid
And subjected to preparative high performance liquid chromatography repeatedly under the following conditions.

Equipment: LC6A system (Shimadzu Corporation) Column: Novapack _C18 (O) was used for radial packs (8φ × 10mm) using a pressure column separation system RCM 8 × 10.
DS4 μm) [both are trade names, manufactured by Waters (USA)].

Eluent: methanol / 0.2M ammonium acetate buffer (p
H7.0) = 7: 3 Sample amount: 1 mg / time Flow rate: 3.0 ml / min A fraction with a retention time of 3 to 4.3 minutes was collected, concentrated under reduced pressure, and lyophilized to obtain 40 mg of a white powder. Was.
This was dissolved in 1N hydrochloric acid (20 ml) and extracted three times with 60 ml of ethyl acetate each time. The organic layers were combined, washed with brine, dried over magnesium sulfate, and the solvent was distilled off under reduced pressure to obtain 33 mg of KS-505 white powder.

The detection of KS-505 during the purification process was performed by using a silica gel plate containing a fluorescent agent [Shirakagel 60F ₂₅₄ plate, Alto 5715 (manufactured by Merck)] and chloroform / methanol /
Thin layer chromatography was performed using a solvent system of ethanol / water (10: 4: 4: 2), and then irradiation with ultraviolet light of 254 nm was performed.

Example 2 96 mg of KS-505 obtained in Example 1 and sodium hydrogen carbonate 2
2 mg and 15 ml of water, and then freeze-dried to obtain K
101 mg of the sodium salt of S-505 was obtained.

Example 3 Tablet KS-505 100 g Lactose 35 g Corn starch 18 g Carboxymethylcellulose Calcium 10 g 10% hydroxypropylcellulose solution (50 g) was added to the above mixture and kneaded. The kneaded liquid is granulated with an extrusion granulator equipped with a 1.0 mm basket, and magnesium stearate (2 g) is added to obtain granules for tableting. 100 mg of KS-505 is contained in one preparation (170 mg) by a conventional method. 8 mm diameter tablets.

Example 4 Capsule KS-505 50 g Lactose 75 g Potato starch 38 g was mixed with 10% hydroxypropylcellulose solution (50 g) and kneaded. Granulation was performed in the same manner as in Example 3, and magnesium stearate (2 g) was added to obtain a capsule containing 50 mg of KS-505 in one capsule (170 mg) by a conventional method.

Example 5 Soft Capsules 10 g of KS-505 was dissolved in 100 g of soybean oil, and the resulting solution was poured into capsules by a conventional method.
A soft capsule containing 10 mg of KS-505 per g) was prepared.

Test Example Anti-amnesic effect test of KS-505.

The effect of KS-505 on learning behavior was examined using a step-through type, one-trial passive avoidance behavior of musk (ddy, male, weight: 24-28 g, 15 animals per group) as an index. KS-505
Used a sodium salt, and physiological saline without KS-505 was used as a control.

The light-dark box apparatus used for the test consisted of a 15 × 9 × 11 cm light room and a 15 × 14 × 18 cm dark room illuminated by a 4 W white fluorescent lamp, and the two rooms were separated by a 3 × 3 cm guillotine door. Have been. The floor in each room is a stainless steel grid floor that allows a weak current to flow from the dark room floor.

KS-505 sodium salt 5, 20, or 50 as test drug
20 μg of physiological saline containing μg was injected into the left ventricle of each test animal using a two-stage needle, and an acquisition test was performed 30 minutes later by the following method. Put the mouse in the light room,
Ten seconds later, the door was opened. Immediately after the limbs of the mouse completely entered the dark room, electricity was supplied to the floor grid and foot shock (Fo) was detected.
An ot shock (0.18 mA, 2000 V for 2 seconds) was applied and immediately removed. Mice that took more than 60 seconds to enter the darkroom from the lightroom were removed from subsequent processing. Immediately after the acquisition attempt, shock shock (25mA, 2.5ms, 2000V)
For amnesia. Twenty-four hours after the amnesia treatment, the mice were placed in a bright room, and ten seconds later, the latency from when the door was opened to when the mice completely entered the dark room was measured. The maximum measurement time was 600 seconds. The latency of mice that took more than 600 seconds was calculated as 600 seconds.

As can be seen from the results shown in Table 3, 5 μg of sodium salt of KS-505 against amnesia due to electroconvulsive shock.
A significant amnesic inhibitory effect was observed in the group administered. Control group I was a group without amnesia treatment without administration of KS-505, control group II was a group with amnesia treatment without administration of KS-505,
Test group III-V is a group to which KS-505 was administered and amnesic treatment was performed.

Effect of the Invention A novel compound KS-505 obtained by culturing a new strain Streptomyces argenteols A-2 has the structure of formula (I). This compound has an anti-amnesic effect and is expected to be useful as a brain function improving agent.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C12R 1: 465) (C12P 33/00 C12R 1: 465) (72) Inventor Toru Yasuzawa 1-2-Imaikecho, Sakai-shi, Osaka 3 (72) Inventor Hiroshi Saito 3-9-13 Nakamachi, Machida City, Tokyo (72) Inventor Hiroshi Sano 7-19-16 Tamagawa Gakuen, Machida City, Tokyo (72) Inventor Shizuo Shiozaki 2162 Harada, Fuji City, Shizuoka Prefecture 9 (72) Inventor Katsuichi Shuto 1-15-19 Fuyodai, Mishima City, Shizuoka Prefecture (58) Fields investigated (Int. Cl. ⁶ , DB name) BIOSIS (DIALOG) WPI (DIALOG) REGISTERY (STN) CA (STN) )

Claims (10)

(57) [Claims] 1. A compound KS-505 represented by the formula (I) and a pharmaceutically acceptable salt thereof. 2. A pharmaceutically acceptable salt comprising a methylamine salt, an ethylamine salt, an aniline salt, a dimethylamine salt,
The compound according to claim 1, which is a diethylamine salt, a pyrrolidine salt, a piperidine salt, a morpholine salt, a piperazine salt, a trimethylamine salt, a triethylamine salt, an N, N-dimethylaniline salt, a pyridine salt, a sodium salt, a potassium salt, a magnesium salt, or a calcium salt. salt. 3. The sodium salt according to claim 2, which is represented by the formula (III). 4. A microorganism belonging to the genus Streptomyces and having the ability to produce the compound KS-505 represented by the formula (I) is cultured in a medium, and the desired compound is accumulated in the culture. Compound KS-505 characterized by being collected
Manufacturing method. 5. The method according to claim 4, wherein the microorganism is Streptomyces argenteolus A-2 (Miyako Kenjo No. 2065). 6. The method according to claim 4, wherein the cells are cultured at a temperature of 20-40 ° C. and a pH of 6-8 for 3-10 days. 7. The method according to claim 4, which is recovered by column chromatography. 8. A pharmaceutical composition for improving brain function, comprising an effective amount of compound KS-505 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier or excipient. 9. A compound obtained by cultivating KS-505, which is capable of producing compound KS-505.
omyces argenteolus) A pure culture of A-2 (Microtechnical Research Institute No. 2065) or a mutant strain of the above microorganism having the ability to produce KS-505. 10. Streptomyces argenteols A
A compound having a cerebral function-improving activity, and a pharmaceutically acceptable salt thereof, which are produced by culturing No.-2 (Microtechnological Research Institute No. 2065) and have the following properties. Form: white powder, acidic substance F _AB mass spectrum: m / z1075 (M + H -H 2 O) + [* 1] and ^{1115 (M + Na) + [} * 2] High resolution F _AB mass spectrum: m / z1115.5903 [ _{* 2] C 61 H 88 O} 17 calcd 1115.5920 measured without added [Note * 1 ... salt as Na. * 2: Measured by adding salt in the usual manner. Molecular formula: C ₆₁ H ₈₈ O ₁₇ ¹ H NMR spectrum: (400 MHz, 10 mg / 0.4 ml, CD ₃ OD solution) δ (ppm): 0.77 (s), 0.80 (br s), 1.05 (d), 1.10
(S), 1.37 (s), 1.52 (m), 1.83 (m), 2.31
(M), 2.45 (m), 2.79 (br t), 2.94 (dd), 3.34
(S), 3.52 (s), 3.61 (br s), 3.72 (m), 3.81
(D), 3.90 (d), 4.36 (d), 7.16 (d), 7.29 (d) ¹³ C NMR spectrum: (100 MHz, 10 mg / 0.4 ml, CD ₃ OD solution) δ (ppm); 11.4 (q) , 15.0 (q), 16.3 (q), 17.4
(Q), 18.2 (t), 18.7 (q), 18.9 (t), 20.2
(T), 20.9 (t), 22.0 (t), 22.6 (t), 23.0
(Q), 23.1 (q), 24.5 (q), 29.6 (t), 34.1
(T), 35.4 (t), 36.7 (t), 38.4 (t), 39.5
(S), 39.7 (t), 39.8 (s), 40.5 (s), 42.8
(S), 43.1 (s), 43.3 (d), 43.4 (t), 44.1
(T), 44.2 (s), 44.4 (d), 45.1 (t), 50.5
(S), 52.3 (q), 53.9 (d), 59.1 (d), 60.3
(T), 61.2 (q), 62.7 (d), 63.2 (t), 64.1
(D), 64.3 (d), 65.1 (d), 65.7 (d), 73.2
(D), 76.7 (d), 77.0 (d), 81.1 (s), 84.7
(D), 88.2 (d), 107.3 (d), 107.6 (s) and 108.0
(S), 122.0 (d), 123.5 (s), 125.4 (d), 126.0
(S), 142.6 (s) and 142.8 (s), 156.1 (s), 170.
2 (s), 172.4 (s), 174.9 (s), 177.7 (s) Infrared absorption spectrum: (KBr method) 3450, 2950, 1730, 1715, 1460, 1385, 1270, 1240, 1120, 1045c
m ^-1 UV absorption spectrum: (λmax, methanol solution) 221 nm (log ε = 4.47), 308 nm (log ε = 3.36) Optical rotation: ▲ [α] ²⁵ _D ▼ = -63.5 ゜ (c0.1, methanol, (Measured immediately after dissolution) Melting point: gradually changes to brown but does not show a clear melting point. Color reaction: Positive for each color reaction with anisaldehyde, sulfuric acid, iodine, bromocresol green, each color reaction with ninhydrin, dinitrophenylhydrazine, ferric chloride, aniline / phthalic acid, and Leydan-Smith reaction, dragen Negative Dorf reaction. Solubility in solvents Soluble in methanol, dimethyl sulfoxide, ethyl acetate, basic water, poorly soluble in hexane, chloroform, acidic water.