JPH06239831A - New physiologically active cysfluoretin, its production and use thereof - Google Patents

Abstract

PURPOSE:To obtain a new physiologically active cysfluoretin having inhibitory activity against glutathione transferases with high specificity. CONSTITUTION:This physiologically active cysfluoretin is expressed by the formula. The compound has the following physicochemical properties: color and form: yellow powder; molecular formula: C25H27O8NS; molecular weight: 501 fast atom bombardment mass spectrometry (FAB-MS) (negative) m/z 500(M-H)<->; melting point: 114-116 deg.C; specific rotatory power: [alpha]<24>D-24 deg. (C 0.5, methanol); solubility: soluble in dimethyl sulfoxide, methanol, acetone and ethyl acetate and insoluble in water and a value of Rf in thin-layer chromatography: 0.20 obtained by using a thin layer of silica gel (Art. 5715 manufactured by Merck & Co., Inc.) and chloroform-ethyl acetate-acetic acid (60:35:5) as a developing solvent. This compound is prepared by culturing a microorganism, belonging to the genus Streptomyces and capable of producing the cysfluoretin, e.g. Streptomyces.sp. M+384-DF12 (FERM BP-3228) in a nutrient culture medium and then collecting the compound from the culture thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel physiologically active substance cisfluoretin having an anti-glutathione transferase activity, its production method and its use.

[0002]

Glutathione transferase is an enzyme localized in the cell membrane and cytoplasm. Inhibitors of cell membrane enzymes have been reported to have immunoregulatory effects [T. Aoyagi, "Protease inhibitor and biological co
ntrol ", Bioactive Metabolites from Microorganisms,
eds by ME Bushell and U. Graefe, No.403 ~
418, Elsevier Science Publishers BV, Amste
rdam, 1989]. Therefore, even an inhibitor of glutathione transferase is expected to have an immunomodulatory action. Furthermore, it has been reported that the membrane-bound glutathione transferase also functions as a leukotriene C ₄ synthase and is deeply involved in inflammation and allergic reaction [protein / nucleic acid / enzyme, Vol. 33, 1564-].
1573 (1988)]. Cytoplasmic glutathione transferase has been reported to be deeply involved in the resistance mechanism of anticancer drug-resistant tumor cells [cancer and chemotherapy,
16: 592-598 (1989)]. Glutathione transferase inhibitors include indomethacin and meclofenam acid.
ic acid) etc. have been reported [Biochemical and Biophy
sical Research Communications, Volume 112, 980
Pp. 985 (1983)].

[0003]

Glutathione transferase inhibitors such as indomethacin and meclophenanoic acid have low specificity for glutathione transferase. Therefore, an inhibitor having high specificity for glutathione transferase is desired. An object of the present invention is to provide a physiologically active substance having such highly specific glutathione transferase inhibitory activity, a method for producing the same, and a use thereof.

[0004]

Means for Solving the Problems The present invention will be summarized. The first invention of the present invention relates to a novel physiologically active substance cisfluoretin, which is represented by the following formula (I):

[Chemical 2] A physiologically active substance cisfluoretin or a pharmaceutically acceptable salt thereof, which is a compound represented by:

The physicochemical properties of cisfluoretin are as follows. Physicochemical properties of cisfluoretine (1) Color and shape: yellow powder (2) Molecular formula: C ₂₅ H ₂₇ O ₈ NS (3) Molecular weight: 501 FAB-MS (Negative) m /
z 500 (MH) ⁻ (4) Melting point: 114 to 116 ° C. (dec.) (5) Specific optical rotation: [α] ²⁴ _D −24 ° (C 0.5,
(Methanol) (6) Ultraviolet absorption spectrum: shown in FIG. 1 of the accompanying drawings. (7) Infrared absorption spectrum: shown in FIG. 2 of the accompanying drawings. (8) Hydrogen nuclear magnetic resonance spectrum: FIG. 3 of the accompanying drawings.
Shown in. (9) Carbon nuclear magnetic resonance spectrum: FIG. 4 of the accompanying drawings.
Shown in. (10) Solubility: dimethyl sulfoxide, methanol,
It is soluble in acetone and ethyl acetate, but insoluble in water. (11) Rf value of thin layer chromatography: 0.20 A thin layer of silica gel (Art. 5715 manufactured by Merck & Co.) was used.
Chloroform-ethyl acetate-acetic acid (6
0: 35: 5) was used. Cisfluoretin may be in the form of a pharmaceutically acceptable salt thereof, and examples of such salts include salts with alkali metals such as sodium, potassium and lithium and alkaline earth metals such as calcium. Can be mentioned.

A second invention of the present invention relates to a method for producing a novel physiologically active substance cisfluoretin, which comprises culturing a cisfluoretin-producing bacterium belonging to the genus Streptomyces in a nutrient medium, This is a production method characterized in that the physiologically active substance cis-fluoretin represented by the above formula (I) is separated and collected.

One example of the cis-fluoretin-producing bacterium used in the present invention is an actinomycete isolated from the soil of Suginami-ku, Tokyo by the present inventors, which is MI384-DF1.
There are strains with the strain number of 2. MI384-DF
The mycological properties of the 12 strains are as follows.

1. Morphology MI384-DF12 strain extends aerial hyphae from basal hyphae branched under a microscope. Aerial aerial hyphae are usually straight, but have helical spore chains, counting spore chains of 20 or more. Pseudosporangium with a diameter of 1.5-6 microns as a characteristic morphology
To form. No limbus or sporangia are observed. The spore size is about 0.5-0.6 x 0.7-0.8 micron and the surface is smooth.

2. Regarding the description of the growth state color in various media, the standard shown in [] below is the color of Continer Corporation of America.
Harmony Manual (Container Corp)
"ation of America" color
Harmony manual) was used. (1) Sucrose / nitrate agar medium (27 ° C. culture) Growth was light brown [4 ng, Lt Brown] to dark tea [3 pn, Dk Brown], and aerial hyphae were not observed. Soluble dyes have a faint brownish tinge. (2) Glucose / asparagine agar medium (27 ° C. culture) Growth is light tea [3ie, Camel] to red tea [5ui,
Rosewood Brown] and aerial hyphae are not observed. Soluble dyes are slightly pink.

(3) Glycerin / asparagine agar medium (ISP-medium 5, 27 ° C. culture) On the growth of tea ash [4 ni, Spice Brown] to dark olive ash [1 po, Ebony], scattered white aerial mycelia To live. Soluble dyes are slightly pink. Developmental tone and soluble pigment is 0.05N-Na
Adds OH to give a green color, but 0.05N-HCl
Was not changed by the addition of. (4) Starch / inorganic salt agar medium (ISP-medium 4,
Culture at 27 ° C.) Brown ash [4 ni, Spice Brown] to dark brown [4
A cotton-like aerial hyphae grow on the growth of pn, Dk Brown]. Soluble dyes have a faint brownish tinge.
The color tone of development and the soluble pigment took on a green color by the addition of 0.05N-NaOH, but did not change by the addition of 0.05N-HCl.

(5) Tyrosine agar medium (ISP-medium 7, culture at 27 ° C.) The growth is grayish green tea [3 ni, Clove Brown] to dark tea [4 nl, Dk Brown], and aerial hyphae are not observed. Soluble dyes have a brownish tinge. (6) Nutrient agar medium (27 ° C. culture) Growth of light tea [3 ng, Yellow Maple]
No settling of gray taste tea [3 ni, Clove Brown] and aerial hyphae was observed. Soluble dyes have a brownish tinge. (7) Yeast-malt agar medium (ISP-medium 2, 2
Cultivation at 7 ° C. White cotton-like aerial hyphae are grown on the development of light yellow tea [2 pg, Must Gold] to light tea [2 ni, Must Brown]. No soluble dye is found.

(8) Oatmeal agar medium (ISP-
Medium 3, culture at 27 ° C) Light gray [13cb, Pearl Gray] aerial hyphae grow slightly and sparsely on the development of light pink [5ba, Shell, Pink] to light yellow tea [21g, Must Tan]. . Soluble dyes are light pink. (9) Glycerin / nitrate agar medium (27 ° C. culture) Growth is pink [6ie, Redwood] to grayish red [6]
1 g, Dk Redwood], no aerial hyphae were observed. Soluble dyes are slightly pale pink. (10) Starch agar medium (27 ° C. culture) Growth light tea [3 ng, Yellow Maple]-
Dark brown [4Pn, DkBrown] and aerial hyphae are not observed. Soluble dyes are slightly pale pink. (11) Lime malate agar medium (27 ° C. culture) Growing thin olive [1le, Olive Yellow
w], aerial hyphae do not settle, and soluble dyes are not recognized.

(12) Cellulose (synthetic solution containing filter paper pieces, cultivated at 27 ° C.) After culturing for 3 weeks, no growth was observed. (13) Gelatin stab culture (15% simple gelatin medium, 20 ° C. culture; glucose / peptone / gelatin medium, 24 ° C. culture) In the case of simple gelatin medium, the growth is light tea, no aerial mycelium does not grow, and a soluble dye Has a brownish tinge. In the glucose-peptone-gelatin medium, the growth is pale yellow tea, aerial hyphae do not grow, and the soluble pigment has a brownish tinge. (14) Skim milk (37 ° C. culture) Growth is light tea, aerial hyphae do not grow, and soluble pigments are brown.

3. Physiological properties (1) Growth temperature range Yeast-starch agar medium (soluble starch 1.0
%, Yeast extract 0.2%, string agar 3.0%, p
H7.0), 20 ° C, 24 ° C, 27 ° C, 30 ° C,
Tested at 37 ℃ and 50 ℃, 20 ℃ and 24 ℃
It grew at ℃, 27 ℃, 30 ℃, 37 ℃, but the growth at 20 ℃ is very poor, it does not grow at 50 ℃. The optimum temperature for growth seems to be around 27 ° C to 30 ° C. (3) Liquefaction of gelatin (15% simple gelatin medium, 2
Culture at 0 ° C; glucose-peptone-gelatin medium, 27
C. Culturing) 15% simple gelatin medium did not show liquefaction, and glucose-peptone-gelatin medium showed weak liquefaction on the 21st day after culturing. Its action is weak.

(3) Hydrolysis of starch (starch
Inorganic salt agar and starch agar, both at 27 ° C
Cultivation) In any medium, water-decomposability is recognized on the 3rd day after culturing, and its action is moderate. (4) Coagulation and peptone conversion of skim milk (Skim milk, 37
C. Cultivation) Peptone formation begins about 6 days after the culture and completes around 13 days. Its action is moderate to strong. Coagulation
unacceptable.

(5) Production of melanin-like pigment (tryptone yeast broth, ISP-medium 1; peptone yeast iron agar medium, ISP-medium 6; tyrosine agar medium, ISP-medium 7; both at 27 ° C. ) Tryptone yeast broth (ISP-medium 1) and peptone yeast iron agar medium (ISP-medium 6) are positive, and tyrosine agar medium (ISP-medium 7) produces a slight melanin-like pigment. (6) Utilization of carbon source (Pridham-Gotrieve agar medium, ISP-medium 9, 27 ° C culture) L-arabinose, D-glucose, D-fructose, sucrose, inositol, and D-mannitol are used for growth. . Probably also utilizes D-xylose. Rhamnose, raffinose and lactose are not used.

(7) Dissolution of lime malate (lime malate agar medium, 27 ° C. culture) Negative. (8) Nitrate reduction reaction (0.1% potassium nitrate-containing peptone water, ISP-medium 8, 27 ° C. culture) Positive. (9) Decomposition of cellulose (synthesis solution with filter paper pieces added, 27 ° C)
Culture) Does not grow.

Summarizing the above properties, MI384-D
The F12 strain, by its morphology, elongates aerial hyphae with helix formation and a characteristic pseudosporangium. 20 spore chains
Counting more than one, the surface is smooth. In various media,
Growth is light to dark brown with pink color on certain media. Although aerial hyphae are not often observed, white aerial hyphae are established in ISP-mediums 2, 3, 4, and 5. The soluble pigment may be pinkish or brownish depending on the medium. The formation of melanin-like pigments is positive, the proteolytic activity is moderate, and the water degradability of starch is also moderate.

The 2,6-diaminopimelic acid contained in the cell wall was LL-type. From these properties, M
The I384-DF12 strain is Streptomyces ( Strep)
It is considered to belong to the group of Searching for closely related known strains revealed the following two as having the pseudospores characteristic of the MI384-DF12 strain. That is, the Streptomyces paradox ( Str
eptomyces paradocus , Inter
national Journal of System
magic Bacteriology, 36, 57
Pp. 3-576, 1986; Systematic a
nd Applied Microbiology; 8
Vol. 61-64, 1986) and Streptomyces Vitaminophilus ( Streptomyces).
Vitaminophilus , Internet
onal Journal of System
cBacterology, 36 volumes, 573-576
P., 1986; Systematic and Ap.
plied Microbiology, 8 volumes, 61-
64, 1986; International J.
individual of Systematic Bacte
riology, 33, 557-564, 1983.
Year). Among them, it was distinguished from Streptomyces vitaminophilus in vitamin requirement. M
I384-DF12 to Streptomyces sp. ( S
treptomyces sp. ) MI384-DF1
It was identified as 2.

The MI384-DF12 strain was applied for deposit at the Institute of Microbial Science and Technology of the Agency of Industrial Science and Technology, and on February 8, 1990, it was entrusted as Microorganism Research Institute No. 11270. 1991
Transferred to the international deposit under the Budapest Treaty on 18th of March, and the Micromachine Research Institute No. 3228 (FERM BP-322
The accession number of 8) is assigned.

The MI384-DF12 strain is likely to change its properties as seen in the case of other actinomycetes. For example, even if it is a mutant strain (spontaneous or inducible) derived from the MI384-DF12 strain, a transfusion or a gene recombinant, all Streptomyces strains having the ability to produce cisfluoretine are of the present invention. It can be used in manufacturing methods.

In the production method of the present invention, the above-mentioned bacteria are cultured in a medium containing nutrients that can be utilized by ordinary microorganisms. As the carbon source, glucose, starch syrup, dextrin, sucrose, starch, molasses, animal / vegetable oil and the like can be used. As a nitrogen source, soybean flour, wheat, wheat germ, corn steep liquor, cottonseed meal, meat extract, peptone,
Yeast extract, ammonium sulfate, sodium nitrate, urea, etc. can be used. In addition, it is effective to add inorganic salts capable of producing sodium, cobalt, chlorine, sulfuric acid, phosphoric acid, and other ions, if necessary. Further, an organic substance and an inorganic substance that help the growth of the bacterium and promote the production of the physiologically active substance cisfluoretin can be appropriately added.

As the culture method, a culture method under aerobic conditions,
The submerged culture method is particularly suitable. The appropriate temperature for culturing is 15
The temperature is ˜37 ° C., but in most cases, culturing is performed at 26˜30 ° C. The production of the physiologically active substance cis-fluoretin differs depending on the medium and culture conditions, but the maximum accumulation is usually reached within 1 to 10 days in both shaking culture and tank culture. When the amount of the physiologically active substance cisfluoretin accumulated in the culture reaches a maximum, the culture is stopped and the target substance is isolated and purified from the culture medium.

When cis-fluoretin obtained from the present invention is collected from a culture solution, it can be extracted and purified by appropriately combining ordinary separation means utilizing its properties. Cisfluoretin is present in both culture filtrate and cells. The culture filtrate can be extracted with a water-immiscible organic solvent such as ethyl acetate. The cells can be extracted with an organic solvent such as methanol or acetone, the extract is concentrated under reduced pressure, and solvent extraction can be performed in the same manner as for the culture filtrate. In addition to the above-mentioned methods, known methods used for collecting fat-soluble substances, for example, adsorption chromatography, gel filtration chromatography, scraping from thin layer chromatography, high performance liquid chromatography, etc. may be combined or repeated as appropriate. Cisfluoretin can be isolated purely.

The pharmaceutically acceptable salt of cisfluoretin can be prepared by a known method, for example, cisfluoretin in a solution containing sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide and the like. Can be obtained by processing.

The third invention of the present invention is a glutathione transferase inhibitor consisting of cisfluoretin or a pharmaceutically acceptable salt thereof and a pharmaceutical additive.
The pharmaceutical additives are not particularly limited, and commonly used ones can be used. The ratio of the active ingredient (cisfluoretin) in the composition cannot be generally determined because it varies depending on the dosage form and the like, but it can be used in a wide range from about 0.05 to 99% by weight. 0.1 to 50% by weight for normal injections
The amount is about 1 to 60% by weight in other formulations. The rest is pharmaceutical additives.

Cisfluoretin strongly inhibits glutathione transferase, which is an enzyme localized in the cell membrane and cytoplasm as shown in the following test example, but it does not show toxicity. Therefore, cisfluoretin is extremely useful as a glutathione transferase inhibitor. Cisfluoretin is usually administered to warm-blooded animals including humans orally or parenterally by intravenous, intracutaneous, intramuscular, or other effective doses to inhibit glutathione transferase in vivo. it can. The dose varies depending on the administration subject, administration route, etc.
0.05-150 mg / Kg / day, 0.5-100 mg / Kg / day,
It is preferably 1 to 50 mg / Kg / day. The formulation for administration includes conventional dosage forms. In the case of oral administration, tablets, granules, capsules and the like, which are molded with a pharmaceutical additive such as an ordinary excipient such as starch, are used. In the case of parenteral administration, usual injections and the like prepared using pharmaceutical additives such as physiological saline and solubilizers are used.

[0028]

INDUSTRIAL APPLICABILITY As described in detail above, the present invention provides a novel physiologically active substance cisfluoretin, which strongly inhibits glutathione transferase. Therefore, it is extremely useful as a glutathione transferase inhibitor.

[0029]

EXAMPLES Next, production examples and formulation examples of the cis-fluoretin of the present invention will be described by way of examples. Example 1 As a seed medium, galactose 2.0%, dextrin 2.0%, Bacto-Soyton (registered trademark) (manufactured by Difco) 1.0%, corn steep liquor (manufactured by Iwaki) 0.5%, Ammonium sulfate 0.2%, calcium carbonate 0.2%, a mixture of silicon KM-70 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a defoaming agent and soybean oil (local method) (mixing ratio 1:
1) A medium containing 0.05% was used. The medium before sterilization was adjusted to pH 7.4 before use.

The seed medium prepared by dispensing 110 ml in a 500 ml Erlenmeyer flask was sterilized at 120 ° C. for 20 minutes, and Streptomyces sp. MI384-DF12 strain (F
ERM BP-3228) 1 to 2 platinum loops of the slant culture was inoculated, and 3 times with a rotary shaker at 30 ° C. and 180 rpm.
The seeds were cultured for one day. Then, as a production medium, glycerin 2.0%, Essan meat (Ajinomoto Co., Ltd.) 1.5
%, Dipotassium hydrogenphosphate 0.1%, cobalt chloride hexahydrate 0.0005% (pH 6.2, adjusted with 1M monopotassium phosphate) to a 500 ml Erlenmeyer flask in 110 ml aliquots at 120 ° C. Sterilize for 20 minutes, 2 ml of the seed culture
Each of them was transplanted and cultured with shaking at 27 ° C. for 4 days. After completion of the culturing, 66 liters of the culture broth was adjusted to pH 4 with 6N hydrochloric acid and filtered to separate into a culture filtrate and cells.

To the wet cells, 18 liters of 75% acetone was added, and the mixture was stirred well to extract the active ingredient. The active ingredient was concentrated to remove acetone, and the pH was adjusted to 2 with 6N hydrochloric acid. Extracted. The ethyl acetate extract was concentrated to obtain 102.4 g of a reddish brown oily substance. This crude material was dissolved in 100 ml of dimethylformamide, 100 g of silanized silica gel (Merck, Art.7719) was added, and the mixture was concentrated to dryness under reduced pressure. Next, this was suspended in 40% methanol, applied to a column of 1000 ml of silanized silica gel previously filled with 40% methanol, and the active ingredient was eluted by a linear concentration gradient elution method of 40% methanol to 100% methanol and concentrated. After drying, 24.4 g of a reddish brown crude material was obtained. This crude material was dissolved in 25 ml of dimethylformamide, and silica gel 60 (Merck, Art.
7734) 25 g was added and the mixture was concentrated to dryness under reduced pressure. Next, this was added to chloroform: methanol: acetic acid (95:
After suspending with 5: 1), it was applied to a column of 1200 ml of silica gel 60 pre-filled with the same mixed solvent and washed with the same mixed solvent. Subsequently, the active ingredient was eluted with chloroform: methanol: acetic acid (90: 10: 1) and concentrated to dryness to obtain 1.4 g of a reddish brown crude substance.

This crude material was added to methanol: acetic acid (100:
1) It was dissolved in 10 ml and applied to a column of 560 ml of Sephadex LH-20 (manufactured by Pharmacia Fine Chemical Co., Ltd.) which had been previously filled with the same mixed solvent, and gel filtration chromatography was carried out using methanol: acetic acid (100: 1) as a solvent. The fraction was concentrated to dryness to obtain 560.0 mg of reddish brown powder. A column for high performance liquid chromatography (HPLC) in which this powder was equilibrated with 35% acetonitrile containing 1% acetic acid in advance (Shiseido Co., Ltd., Capsule _C18 , 20Φ × 250 mm, flow rate 8)
ml / min) and elute with the above equilibrium solution. The active fraction obtained is concentrated to dryness, 20 ml of ethyl acetate and 20 ml of water are added to adjust the pH to 2 with 2N hydrochloric acid, and the mixture is stirred well to be effective. The components were extracted and the ethyl acetate layer was concentrated to give 28.2 mg of pure cis-fluoretin yellow powder.

Using pure cisfluoretin, ultraviolet absorption spectrum, infrared absorption spectrum, hydrogen nuclear magnetic resonance spectrum and carbon nuclear magnetic resonance spectrum were measured, and these spectra are shown in FIG. 1, FIG. 2, FIG. It is shown in FIG. Tracing of cisfluoretin during the culture and purification steps was based on the measurement of anti-glutathione transferase activity. As the method, the same method as the method for measuring glutathione transferase inhibitory activity shown in the test example described later was used.

Example 2 20 parts by weight of cis-fluoretin, 80 parts of crystalline lactose, 98 parts of crystalline cellulose and 2 parts of magnesium stearate were mixed with V
The tablets were compressed with a mold mixer to give tablets of 200 mg each.

[0035]

[Test Example] The test example below shows that cis-fluoretin has glutathione transferase inhibitory activity and does not show toxicity. Test Example 1 Inhibition of cis-fluoretine glutathione transferase
Harmful activity glutathione transferase inhibitory activity is Biochemi
cal and BiophysicalResearch Communications, 1st
Volume 12, pages 980-985 (1983). That is, 0.1 ml of 90 mM glutathione (reduced form), 0.05 ml of 20 mM 3,4-dichloronitrobenzene, and 0.1 M potassium phosphate buffer (pH 7.
4) 1.7 ml and a mixed solution containing 0.1 ml of an aqueous solution containing a specimen were heated at 37 ° C. for 3 minutes, and then a DEAE-cellulose column from a rat liver homogenate, a glutathione transferase solution partially purified by ammonium sulfate salting out 0 0.05 ml was added, and the mixture was reacted at 37 ° C. for 30 minutes.

After the reaction, the absorbance (a) at 345 nm was measured. At the same time, the blind absorbance (b) using only the buffer solution containing no sample was measured, and the glutathione transferase inhibition rate was calculated by [(ba) / b] × 100. The concentration of the sample showing a 50% inhibition rate was taken as the value of IC ₅₀ . Pure cis-fluoretin was 18.2μ in this assay
50% glutathione transferase at a concentration of g / ml
Inhibited.

Test Example 2 Toxicity of cisfluoretin Cisfluoretin was intraperitoneally administered to mice to examine its toxicity. No toxicity was observed even at 100 mg / kg.

[Brief description of drawings]

FIG. 1 shows an ultraviolet absorption spectrum of a 10 μg / ml 90% methanol solution of cisfluoretin.

FIG. 2 shows an infrared absorption spectrum of cisfluoretin in a potassium bromide tablet.

FIG. 3: 4 of cisfluoretin measured in heavy acetone
The 00MHz hydrogen nuclear magnetic resonance spectrum is shown.

FIG. 4: 1 of cisfluoretin measured in heavy acetone
A 00MHz carbon nuclear magnetic resonance spectrum is shown.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI technical display location // (C12P 15/00 C12R 1: 465) (72) Inventor Yasuhiko Muraoka 3-11- Takashimadaira, Itabashi-ku, Tokyo 2-1107 (72) Inventor Takayuki Aoyama 3-17-2-302 Shimoge, Kita-ku, Tokyo

Claims (3)

[Claims] 1. The following formula (I): A physiologically active substance cisfluoretin or a pharmacologically acceptable salt thereof, which is a compound represented by: 2. A physiologically active substance, cisfluoretin, which comprises culturing a cisfluoretin-producing bacterium belonging to the genus Streptomyces in a nutrient medium and collecting the cisfluoretin according to claim 1 from the culture. Manufacturing method. 3. A glutathione transferase inhibitor comprising the cisfluoretin according to claim 1 or a pharmaceutically acceptable salt thereof and a pharmaceutical additive.