JP2022122305A - antibacterial agent - Google Patents

Abstract

A novel antibacterial agent is provided. An antibacterial agent containing at least one selected from the group consisting of a compound represented by formula (1), a prodrug thereof, a salt thereof, and a solvate thereof. TIFF2022122305000015.tif45170 [selection drawing] None

Description

The present invention relates to antibacterial agents and the like.

Bacterial infections are usually treated by bacteriostasis or sterilization of causative bacteria by the action of antibacterial agents. However, the use of an antibacterial agent results in the emergence of drug-resistant bacteria against the antibacterial agent. For example, methicillin-resistant Staphylococcus aureus (MRSA) is known to emerge in hospitals where antibacterial agents are frequently used and to be the cause of outbreaks. In addition, although measures against bacterial infections are also required in livestock farms, the use of the same antibacterial agent for both humans and livestock promotes multidrug resistance of pathogenic bacteria. Therefore, the development of new antibacterial agents is required as a countermeasure against multidrug-resistant bacteria and for deterrence of multidrug resistance.

Griseolutein A has been reported to have antibacterial activity against Staphylococcus aureus (Non-Patent Document 1). However, it has not been reported that griseolutein A can exert an antibacterial effect against drug-resistant bacteria. In addition, it has not been reported that griseolutein A can also exhibit antibacterial activity against Gram-negative bacteria.

Mar. Drugs 2020, 18, 243 Hifnawy et., al. Journal of the Chemical Society D: Chemical Communications, 1970, Issue 21, Pages 1423 to 1425.

An object of the present invention is to provide a new antibacterial agent.

As a result of intensive research in view of the above problems, the present inventors selected from the group consisting of compounds represented by the following general formula (1), prodrugs thereof, salts thereof, and solvates thereof We have found that the above problems can be solved by an antibacterial agent containing at least one. The present inventor has completed the present invention as a result of further research based on this finding. That is, the present invention includes the following aspects.

Section 1. General formula (1):

で表される化合物、そのプロドラッグ、それらの塩、及びそれらの溶媒和物からなる群より選択される少なくとも1種を含有する、抗菌剤。

An antibacterial agent containing at least one selected from the group consisting of compounds represented by, prodrugs thereof, salts thereof, and solvates thereof.

Section 2. Item 2. The antibacterial agent according to Item 1, which is an antibacterial agent against at least one selected from the group consisting of Gram-positive bacteria and Gram-negative bacteria.

Item 3. Item 3. The antibacterial agent according to Item 1 or 2, which is an antibacterial agent against at least one selected from the group consisting of drug-resistant bacteria and drug-susceptible bacteria.

Section 4. Item 4. The antibacterial agent according to any one of Items 1 to 3, which is an antibacterial agent against staphylococci.

Item 5. Item 5. The antibacterial agent according to any one of Items 1 to 4, which is an antibacterial agent against Staphylococcus aureus.

Item 6. Item 6. The antibacterial agent according to any one of Items 1 to 5, which is a medicine or reagent.

Item 7. General formula (1):

で表される化合物の生産能を有する、ストレプトマイセス属細菌。

Streptomyces bacterium having the ability to produce the compound represented by.

Item 8. Item 8. The Streptomyces bacterium according to Item 7, which is Streptomyces strain HEK131 (Accession number of the Patent Microorganisms Depositary: NITE P-03335).

Item 9. General formula (1), comprising the step of recovering the culture of bacteria according to Item 7 or 8:

で表される化合物を製造する方法。

A method for producing a compound represented by

Item 10. Item 9. The method according to Item 9, wherein the culture is a co-culture of the bacterium according to Item 7 or 8 and other bacteria.

Item 11. The other bacteria consist of Tsukamurella bacteria, Corynebacterium bacteria, Rhodococcus bacteria, Gordonia bacteria, Dietsia bacteria, Nocardia bacteria, Skermania bacteria, Willamdia bacteria, and Mycobacterium bacteria. Item 11. The method according to Item 10, which is at least one selected from the group.

Item 12. General formula (1):

で表される化合物、そのプロドラッグ、それらの塩、又はそれらの溶媒和物。

A compound represented by, a prodrug thereof, a salt thereof, or a solvate thereof.

ADVANTAGE OF THE INVENTION According to this invention, a new antibacterial agent can be provided.

2 shows test results of Example 2. FIG. The vertical axis indicates the relative cell number, and the horizontal axis indicates the griseolutein T concentration.

As used herein, the expressions "contain" and "include" include the concepts "contain", "include", "consist essentially of" and "consist only of".

1. In one aspect of the present invention, a compound represented by general formula (1):

で表される化合物（本明細書において、「本発明の化合物」又は「Griseolutein T」と示すこともある。）、そのプロドラッグ、それらの塩、又はそれらの溶媒和物（本明細書において、これらをまとめて「本発明の有効成分」と示すこともある。）に関する。以下、これらについて説明する。

Compound represented by (herein, "compound of the present invention" or "Griseolutein T".), its prodrugs, their salts, or their solvates (herein, These may be collectively referred to as "the active ingredient of the present invention"). These will be described below.

A prodrug of the compound of the present invention refers to a compound that is converted to the compound of the present invention by a reaction with an enzyme, gastric acid, or the like in vivo. Prodrugs of the compounds of the present invention include, for example, compounds in which the -NH- moiety is acylated, alkylated, phosphorylated (e.g., compounds in which the -NH- moiety of the compounds of the present invention is eicosanoylated, alanylated, alkylated (eg pentyl)aminocarbonylation, (5-alkyl (e.g. methyl)-2-oxo-1,3-dioxolen-4-yl)alkoxy (e.g. methoxy)carbonylation, tetrahydrofuranylation, pyrrolidylalkyl (e.g. methyl)ation, pivaloyloxyalkyl (e.g. methyl), acetoxyalkyl (e.g. methyl), tert-butylated compounds, etc.); hydroxyl group acylated, alkylated, phosphorylated, borated compounds (e.g., the present invention The hydroxyl group of the compound is acetylated, palmitoylated, propanoylated, pivaloylated, succinylated, fumalylated, alanylated, dialkyl (e.g. methyl) aminoalkyl (e.g. methyl) carbonylated compounds); is an esterified or amidated compound (for example, the carboxy group of the compound of the present invention is alkyl (e.g. ethyl) esterified, aryl (e.g. phenyl) esterified, carboxyalkyl (e.g. methyl) esterified, dialkyl (e.g. methyl) aminoalkyl (e.g. methyl) esterification, pivaloyloxyalkyl (e.g. methyl) esterification, 1-{(alkoxy (e.g. ethoxy)carbonyl)oxy}alkyl (e.g. ethyl) esterification, phthalidyl esterification, (5- Alkyl (e.g. methyl)-2-oxo-1,3-dioxolen-4-yl)alkyl (e.g. methyl) esterification, 1-{[(cycloalkyl (e.g. cyclohexyl)oxy)carbonyl]oxy}alkyl (e.g. ethyl) esterification, alkyl (eg, methyl)amidated compounds, etc.). These compounds can be produced by methods known per se. In addition, the prodrug of the compound of the present invention changes to the compound of the present invention under physiological conditions as described in Hirokawa Shoten 1990, "Drug Development", Vol. 7, "Molecular Design", pp. 163-198. can be anything.

Salts of the compounds of the present invention and prodrugs thereof are not particularly limited as long as they are pharmaceutically acceptable salts. As the salt, both acid salts and basic salts can be employed. Examples of acid salts include mineral salts such as hydrochloride, hydrobromide, sulfate, nitrate, phosphate; acetate, propionate, tartrate, fumarate, maleate, malic acid. Salts, organic acid salts such as citrate, methanesulfonate, p-toluenesulfonate, etc. Examples of basic salts include alkali metal salts such as sodium salt and potassium salt; alkaline earth metal salts such as salts; salts with ammonia; morpholine, piperidine, pyrrolidine, monoalkylamine, dialkylamine, trialkylamine, mono(hydroxyalkyl)amine, di(hydroxyalkyl)amine, tri(hydroxyalkyl) Examples thereof include salts with organic amines such as amines.

The compounds of the present invention, prodrugs thereof, and salts thereof can also be hydrates and solvates. Solvents include, for example, pharmaceutically acceptable organic solvents (eg, ethanol, glycerol, acetic acid, etc.) and the like.

2. Methods of Preparation The compounds of the present invention can be synthesized and prepared by a variety of methods. The compound of the present invention can be synthesized, for example, by referring to the method described in Non-Patent Document 2 and appropriately modifying it. The compounds of the present invention can also be suitably produced by a method comprising recovering a culture of Streptomyces bacteria capable of producing the compounds of the present invention. This manufacturing method will be described below.

The Streptomyces bacterium is not particularly limited as long as it belongs to the genus Streptomyces, for example S. abietis, S. abikoensis, S. aburaviensis, S. baarnensis, S. bacillaris, S. badius , S. cacaoi, S. caelestis, S. caeruleatus, S. candidus, S. decoyicus, S. demainii, S. deserti, S. diastaticus, S. erythraeus, S. erythrogriseus, S. eurocidicus, S. felleus, S. fenghuangensis, S. ferralitis, S. fervens, S. filamentosus, S. fildesensis, S. glaucosporus, S. glaucus, S. globisporus, S. glomeratus, S. glomeroaurantiacus, S. hirsutus, S. hokutonensis, S. hoynatensis , S. humidus, S. javensis, S. jietaisiensis, S. jiujiangensis, S. kaempferi, S. kanamyceticus, S. karpasiensis, S. laceyi, S. lacticiproducens, S. laculatispora, S. ladakanum, S. malachitospinus, S. malaysiensis, S. marinus, S. narbonensis, S. nashvillensis, S. netropsis, S. olivaceiscleroticus, S. olivaceoviridis, S. olivaceus, S. olivochromogenes, S. paradoxus, S. parvisporogenes, S. parvulus, S. qinglanensis , S. racemochromogenes, S. radiopugnans, S. rameus, S. sanglieri, S. sannanensis, S. sanyensis, S. tauricus, S. tendae, S. te rmitum, S. umbrinus, S. variabilis, S. variegatus, S. varsoviensis, S. wedmorensis, S. wellingtoniae, S. werraensis, S. willmorei, S. xanthocidicus, S. xantholiticus, S. xanthophaeus, S. yaanensis, S. yanglinensis, S. yanii, S. zhaozhouensis, S. zinciresistens, S. ziwulingensis and the like. Streptomyces bacterium particularly preferably includes Streptomyces strain HEK131 (Accession number of the Patent Microorganism Depository Center: NITE P-03335). Streptomyces can be used singly or in combination of two or more.

The culture is the culture medium itself (including the cells) obtained by the step of culturing Streptomyces bacteria (the culture solution when the medium is liquid), and is obtained from the culture medium through the step of removing the cells. medium components (culture supernatant if the medium is liquid), or bacterial cell components. In the production of the compound of the present invention, preferably, the culture medium itself containing the cells can be used as the "culture".

The culture can be a co-culture of Streptomyces bacteria and other bacteria. As other bacteria, bacteria having the ability to induce the production of secondary metabolites of bacteria belonging to the genus Streptomyces are preferred. Such bacteria include, for example, bacteria having mycolic acid in their cell walls, coryneform bacteria, and the like. More specifically, for example, bacteria of the genus Tsukamullera, bacteria of the genus Corynebacterium, bacteria of the genus Rhodococcus, bacteria of the genus Gordonia, bacteria of the genus Dietzia, and bacteria of the genus Nocardia Bacteria, bacteria belonging to the genus Skermania, bacteria belonging to the genus Williamsia, bacteria belonging to the genus Mycobacterium, and the like. C.efficiens, C.glutamicum, G.rubripertincta, R.coprophilus, R.erythropolis, R.erythropolis R. wratislaviensis, R. zopfii, and the like, more specifically T. pulmonis TP-B0596 strain, C. efficiens ) NBRC100395 strain, C. glutamicum ATCC13869 strain, G. rubripertincta strain JCM3204, R. coprophilus strain JCM3200, R. erythropolis strain NBRC100887 , R. wratislaviensis JCM9689 strain, R. zopfii JCM9919 strain, and the like. Among these, bacterium belonging to the genus Tsukamurella is preferable, Tsukamurella pulmonis is more preferable, and Tsukamurella pulmonis TP-B0596 strain is more preferable. Other bacteria can be employed singly or in combination of two or more.

The method of obtaining a co-culture is not particularly limited as long as it is a method of culturing under conditions that allow contact between Streptomyces bacteria and other bacteria. Typically, Streptomyces bacteria and other bacteria can be added and cultured in a liquid medium.

Cultivation can be performed according to or according to a known culture method for Streptomyces bacteria.

The medium is not particularly limited, and as a medium for Streptomyces spp., a known medium can be used as it is or appropriately modified. Liquid media include, for example, 0.2-1.0% (preferably 0.4-0.6%) glucose, 1.0-3.0% (preferably 1.5-2.5%) soluble starch, 1.0-3.0% (preferably 1.5-2.5%) glycerol, 0.1 A liquid medium (especially preferably A3M medium) containing ~0.3% yeast extract and 1.0-2.0% seed (eg, cotton seed) pulverized material can be mentioned. In addition to these, for example, A11M medium, A16 medium and the like are also included. The pH of the medium is, for example, 7.0-8.0, preferably 7.0-7.5. The medium used is usually sterilized by heat (for example, by autoclaving).

The culture temperature is not particularly limited as long as the Streptomyces bacteria can be cultured, and is, for example, 15 to 45°C, preferably 25 to 35°C.

The culture time is not particularly limited as long as the compound of the present invention can be produced, and is, for example, 8 hours to 2 weeks, preferably 16 hours to 1 week.

The compound of the present invention is contained in the culture medium itself, medium components, and bacterial cell components obtained by the culture, and the compound of the present invention can be obtained by collecting these. It is desirable to purify these as necessary.

Purification can be performed according to or according to known methods. Purification methods include, for example, organic solvent (eg, butanol) extraction, chromatography (eg, silica gel chromatography, reversed-phase chromatography, etc.), and the like. Elution is preferably carried out in multiple stages. In the first step, elution can preferably be performed with a solvent obtained by adding acetonitrile to an aqueous solution containing trifluoroacetic acid. The concentration of trifluoroacetic acid is relatively low, for example about 0.05-0.2%. Since it is known that the compound of the present invention is eluted when the acetonitrile concentration is above a certain level (see Example 1-3), it is preferable to perform gradient elution or stepwise elution using this. . From the second step onward, elution can preferably be performed with a solvent obtained by adding methanol to an aqueous solution containing ammonium acetate. The concentration of ammonium acetate is, for example, about 15-25 mM. Since it is known that the compound of the present invention is eluted when the methanol concentration is above a certain level (see Example 1-3), it is preferable to perform gradient elution or stepwise elution using this. . Specifically, purification can be performed using antibacterial activity (preferably antibacterial activity against both Gram-positive and Gram-negative bacteria) as an index (for example, according to or according to the method of Examples 1-3 below).

The compound of the present invention can also be obtained by subjecting the compound obtained above as a starting material to a known synthesis reaction or a synthesis reaction analogous thereto.

3. Use The active ingredient of the present invention has antibacterial activity. Therefore, the active ingredient of the present invention can be used as an active ingredient of an antibacterial agent in various fields such as pharmaceuticals and reagents. Therefore, in one aspect, the present invention relates to an antibacterial agent (also referred to herein as the "antibacterial agent of the present invention") containing at least one of the active ingredients of the present invention.

The antibacterial agent of the present invention is not particularly limited as long as it contains the active ingredient of the present invention, and may further contain other ingredients as necessary. Other ingredients are not particularly limited as long as they are pharmaceutically acceptable ingredients. Other components include additives as well as components having pharmacological action. Examples of additives include bases, carriers, solvents, dispersants, emulsifiers, buffers, osmotic pressure regulators, absorption enhancers, stabilizers, excipients, binders, disintegrants, lubricants, thickeners. , moisturizing agents, coloring agents, fragrances, chelating agents, and the like.

The target bacteria of the antibacterial agent of the present invention can be widely used regardless of Gram-negative bacteria or Gram-positive bacteria, drug-resistant bacteria or drug-sensitive bacteria. Gram-negative bacteria include, for example, Enterobacteriaceae (e.g., Escherichia, Klebsiella, Salmonella, Shigella, etc.), Acinetobacter, Pseudomonas (e.g., Pseudomonas aeruginosa), Moraxella Bacteria, Helicobacter, Campylobacter, Aeromonas, Vibrio (e.g. Vibrio cholerae, Vibrio parahaemolyticus), Haemophilus (e.g. Haemophilus influenzae), Neisseria (e.g. Neisseria gonorrhoeae, Meningococcus), Bacteroides genus fungi and the like. Gram-positive bacteria include, for example, staphylococci (e.g., Staphylococcus aureus, Staphylococcus epidermidis, etc.), enterococci (e.g., Enterococcus), streptococci (e.g., group A streptococci, group B streptococci, pneumonia Streptococcus violet), Bacillus (e.g. Bacillus cereus, Bacillus anthracis), Clostridia (e.g. Tetanus, Clostridium botulinum, Clostridium difficile), Corynebacterium (e.g. Diphtheria), Listeria, Lactobacillus genus Bifidobacterium, Propionibacterium (for example, P. acnes causing acne), actinomycetes, and the like. Among these, Gram-positive bacteria are preferred, Staphylococcus aureus is more preferred, and Staphylococcus aureus is more preferred. The antibacterial agent of the present invention can exert a high antibacterial effect even against drug-resistant bacteria.

The mode of use of the antibacterial agent of the present invention is not particularly limited, and an appropriate mode of use can be adopted according to its type. The antibacterial agent of the present invention can be used, for example, in vitro (for example, added to the medium of cultured cells) or in vivo (for example, administered to animals), depending on its use. can also

When the antibacterial agent of the present invention is applied to animals or cells, the application target is not particularly limited. Examples include goats and deer. Moreover, animal cells etc. are mentioned as a cell. The types of cells are not particularly limited, such as blood cells, hematopoietic stem cells/progenitor cells, gametes (sperm, ovum), fibroblasts, epithelial cells, vascular endothelial cells, nerve cells, hepatocytes, keratinocytes, muscle cells. , epidermal cells, endocrine cells, ES cells, iPS cells, tissue stem cells, cancer cells and the like.

The antibacterial agent of the present invention can be used in any dosage form suitable for pharmaceuticals, reagents, etc., such as tablets (including orally disintegrating tablets, chewable tablets, effervescent tablets, lozenges, jelly drops, etc.), pills, granules, etc. Oral formulations such as formulations, fine granules, powders, hard capsules, soft capsules, dry syrups, liquids (including drinks, suspensions, and syrups), jelly, and injection formulations (e.g., drip Injections (e.g. preparations for intravenous infusion, etc.), intravenous injections, intramuscular injections, subcutaneous injections, intradermal injections), external preparations (e.g. ointments, creams, poultices, lotions), suppositories Parenteral formulations such as inhalants, eye drops, eye ointments, nose drops, ear drops, and liposomes can be used.

The route of administration of the antibacterial agent of the present invention is not particularly limited as long as the desired effect is obtained. , parenteral administration such as intracardiac administration, subcutaneous administration, intradermal administration, and intraperitoneal administration.

The content of the active ingredient in the antibacterial agent of the present invention depends on the mode of use, the target of application, the state of the target of application, etc., and is not limited, but for example, 0.0001 to 100% by weight, preferably 0.001 to 50%. % by weight.

When the antibacterial agent of the present invention is administered to humans or animals, the dosage is not particularly limited as long as it is an effective amount that exhibits efficacy. 0.1 to 1000 mg/kg body weight per day, preferably 0.5 to 500 mg/kg body weight per day, and 0.01 to 100 mg/kg body weight per day, preferably 0.05 to 50 mg/kg for parenteral administration. Weight. The above dosage can be adjusted appropriately according to the patient's age, condition, symptoms, and the like.

EXAMPLES The present invention will be described in detail below based on examples, but the present invention is not limited by these examples.

Example 1. Preparation of Griseolutein T <Example 1-1. Preparation of culture>
Streptomyces sp. HEK131 strain (Accession number: NITE P-03335) glycerol stock stored at -80℃ on ISP2 agar medium (1% Malt extract, 0.4% Yeast extract, 0.4% Glucose, 2% Agar) Streak inoculated and incubated for 3 days at 30°C. Streptomyces sp. HEK131 grown on ISP2 agar medium was inoculated into a K-1 flask containing 100 ml of ISP2 liquid medium (1% Malt extract, 0.4% yeast extract, 0.4% glucose) and incubated at 30℃. Rotating shaking culture was carried out at 200 rpm for 2 days to prepare a preculture medium in which the growth had reached the stationary phase.

On the other hand, ISP2 agar medium was inoculated with Tsukamurella pulmonis TP-B0596 stored at -80°C from a glycerol stock and incubated at 30°C for 2 days. T. pulmonis TP-B0596 grown on ISP2 agar medium was inoculated into a K-1 flask containing 100 ml of ISP2 liquid medium, and cultured with rotary shaking at 30°C and 200 rpm for 2 days until the growth reached stationary phase. A pre-culture medium was prepared.

Add 3% Streptomyces sp. HEK131 pre-culture solution ( v/v), and at the same time, 1% (v/v) of T. pulmonis TP-B0596 preculture solution was added, and shaking culture was performed at 30°C and 200 rpm for 1 to 4 days, and Streptomyces sp. HEK131 and A co-culture (100 mL×4) with T. pulmonis TP-B0596 was obtained.

On the other hand, 3% (v/v) of Streptomyces sp. HEK131 preculture was added to A3M liquid medium, and cultured with shaking at 30°C and 200 rpm for 1 to 4 days to obtain a single culture of Streptomyces sp. HEK131. (100 mL x 4) was obtained.

<Example 1-2. Extract>
Each co-culture and monoculture was mixed with ½ volume of 1-butanol for 1 hour at 30° C. and 150 rpm shaking. The mixture was dispensed into centrifuge tubes and centrifuged at 4000 rpm for 8 minutes. The upper layers were combined, concentrated by an evaporator, and dried in a vacuum to obtain 974 mg and 812 mg of butanol extracts of the co-culture and monoculture, respectively.

<Example 1-3. Purification>
A butanol extract (243 mg) of the co-culture was fractionated by preparative HPLC. A Develosil ODS HG-5 column (2 cm inner diameter, 25 cm length) was used, and the solvent was a gradient elution of 20-80-100% (0-60-65 min) MeCN-0.1% TFA at a flow rate of 6 mL/ Fractionated every 2 minutes at min. The fraction eluted at 26-28 minutes was concentrated to obtain an antibacterial fraction YI-I-136-2 (2.5 mg). The butanol extract (731 mg) of the co-culture was similarly fractionated by preparative HPLC to give fraction YI-I-173-4 (4.9 mg) corresponding to YI-I-136-2. The two antimicrobial fractions were combined and fractionated by preparative HPLC. A Develosil ODS HG-5 column (2 cm inner diameter, 25 cm length) was used, and the solvent was a gradient elution of 20-70-100% (0-50-60 min) MeOH-20 mM NH ₄ OAc at a flow rate of 5. Fractionated every 1.5 minutes at mL/min. Fractions eluted at 49.5-52.5 minutes were concentrated to obtain an antibacterial fraction YI-I-179-1 (1.6 mg). This fraction was further fractionated by preparative HPLC. Develosil ODS HG-5 (inner diameter: 2 cm, length: 25 cm) was used as a column, 25% MeOH-20 mM NH ₄ OAc was used as the solvent, and elution was performed at a flow rate of 6 mL/min. The peak eluted at 40.2 minutes was fractionated, concentrated and lyophilized to give griseolutein T (0.16 mg).

Two portions of the butanol extract (812 mg) of the monoculture were fractionated by preparative HPLC. A Develosil ODS HG-5 column (2 cm inner diameter, 25 cm length) was used, and the solvent was a gradient elution of 20-80-100% (0-60-65 min) MeCN-0.1% TFA at a flow rate of 6 mL/ Fractionated every 2 minutes at min. Fractions eluting at 22-24 minutes were combined and concentrated to give fraction YI-II-39-5 (3.5 mg) containing griseolutein T. Since the content of griseolutein T was low, further purification was not performed, and the content was measured by the method shown in 1-4.

<Example 1-4. Quantitative Analysis>
Using purified griseolutein T as a standard, quantitative analysis of griseolutein T in fractions during purification was performed under the following conditions. Develosil ODS UG-5 (4.6 mm id, 25 cm length), 20-40% (20 min) MeOH-20 mM NH4OAc, 1 mL/min, _UV280 nm. The results are as follows.
Fraction YI-I-173-4 from co-culture: 2.6 mg/L
Fraction YI-II-39-5 from monoculture: 0.16 mg/L.

<Example 1-5. Structural Analysis>
The chemical structure of griseolutein T was determined as follows by analysis centered on two-dimensional NMR analysis (DQF-COSY, HSQC, HMBC). The thick line in the right panel indicates the bond determined by DQF-COSY, and the arrow indicates the C→H correlation in HMBC for determining 2- or 3-bond linkages. The chemical shift values are summarized in the table below.

High resolution MS (ESI-TOF, positive) gives m/z _327.0993 (calculated for _C17H15N2O5 [M _- OH] ⁺ : _327.0975 ) and m/z _{367.0910 ( C17H16N2} Calculated as _O6Na [M+Na] ⁺ : _367.0901 ) ion peak was observed, supporting the molecular _{formula C17H16N2O6} of _gliseolutein T.

Example 2. Evaluation of antibacterial activity in type strain
Glycerol stocks of test strains (Table 2) stored at -80°C were streak-inoculated onto LB agar medium (1% Trypton, 0.5% Yeast Extract, 0.5% NaCl, 1.5% Agar) and incubated overnight at 37°C. did. The grown strains to be tested were suspended in physiological saline (0.9% NaCl) and adjusted to a McFarland turbidity of 0.5. Dilute the adjusted bacterial solution 200 times for NDM6, MCR1, and E. coli, and 50 times for MRSA with Mueller Hinton II (Cation-Adjusted) medium (0.3% Beef Extract, 1.75% Acid Hydrolysate of Casein, 0.15% Starch). Then, 4 types of test bacterial solutions were prepared.

The purified griseolutein T was dissolved in a 10% DMSO aqueous solution and adjusted to 10 times the test concentration. As a control sample, a mixed aqueous solution of colistin sulfate (test concentration 64 μg/mL) and ampicillin sodium (test concentration 128 μg/mL) and sterilized water were also adjusted in the same manner. 10 μL of the griseolutein T solution prepared in a 96-well flat-bottom multiplate and 90 μL of the test bacterial solution were mixed, incubated at 37° C. for 18 hours, and then absorbance at 600 nm was measured. The relative cell number (%) was calculated by setting the absorbance of the control sample of sterilized water to 100% and the absorbance of the control sample of the mixed aqueous solution of colistin sulfate and ampicillin sodium to 0%.

The results are shown in FIG. It was found that griseolutein T can exhibit antimicrobial activity against both Gram-positive and Gram-negative bacteria, and against various drug-resistant bacteria.

Example 3. Evaluation of antibacterial activity in clinical isolates
Glycerol stocks of 87 test strains of different origins (Table 3) stored at -80 ° C were streaked on LB agar medium (1% Trypton, 0.5% Yeast Extract, 0.5% NaCl, 1.5% Agar), Incubate overnight at 37°C. Each test strain that grew on the agar medium and formed a single colony was again streak-inoculated onto another LB agar medium and incubated overnight at 37°C. The grown strains to be tested were suspended in Mueller Hinton II (Cation-Adjusted) medium and adjusted to a McFarland turbidity of 0.5. The adjusted bacterial solution was diluted 180-fold with Mueller Hinton II (Cation-Adjusted) medium to prepare 87 test bacterial solutions.

The purified griseolutein T was dissolved in a 10% DMSO aqueous solution to adjust the concentration to 10 times the test concentration, and then the purified griseolutein T was dissolved in a 10% DMSO aqueous solution to adjust the concentration to 10 times the test concentration. As a control sample, a mixed aqueous solution of colistin sulfate (test concentration 64 μg/mL) and ampicillin sodium (test concentration 128 μg/mL) and sterilized water were also adjusted in the same manner. Mix 10 μL of Griseolutein T solution prepared in a 96-well round-bottom multiplate and 90 μL of the test bacteria solution, incubate at 37°C for 18 hours, and then measure the amount of growth from the sedimentation of bacteria on the bottom of the 96-well round-bottom multiplate. Judged. If the amount of bacteria precipitated was about the same as the negative control (sterilized water (no drug)), it was judged to be "no effect", and if the amount of bacteria precipitated was less than the negative control, it was judged to be "growth suppression". A case in which no sedimentation of bacteria was observed was determined as "growth inhibition".

Table 4 shows the results. It was found that griseolutein T can exert an antibacterial effect against both drug-resistant bacteria and drug-sensitive bacteria, and also against various drug-resistant bacteria. In addition, it was found that griseolutein T can exert a particularly strong antibacterial effect against Staphylococcus aureus. Based on the results of Example 1 (Fig. 1), it is considered that the antibacterial action can be confirmed by increasing the concentration even for strains for which the effect could not be confirmed in this test.

Claims (12)

General formula (1):

An antibacterial agent containing at least one selected from the group consisting of compounds represented by, prodrugs thereof, salts thereof, and solvates thereof. 2. The antibacterial agent according to claim 1, which is an antibacterial agent against at least one selected from the group consisting of Gram-positive bacteria and Gram-negative bacteria. 3. The antibacterial agent according to claim 1, which is an antibacterial agent against at least one selected from the group consisting of drug-resistant bacteria and drug-susceptible bacteria. The antibacterial agent according to any one of claims 1 to 3, which is an antibacterial agent against staphylococci. The antibacterial agent according to any one of claims 1 to 4, which is an antibacterial agent against Staphylococcus aureus. The antibacterial agent according to any one of claims 1 to 5, which is a medicine or reagent. General formula (1):

Streptomyces bacterium having the ability to produce the compound represented by. 8. The bacterium of the genus Streptomyces according to claim 7, which is Streptomyces strain HEK131 (Accession number of the Patent Microorganisms Depositary: NITE P-03335). General formula (1), comprising recovering the culture of bacteria according to claim 7 or 8:

A method for producing a compound represented by 10. The method of claim 9, wherein said culture is a co-culture of the bacterium of claim 7 or 8 and another bacterium. The other bacteria consist of Tsukamurella bacteria, Corynebacterium bacteria, Rhodococcus bacteria, Gordonia bacteria, Dietsia bacteria, Nocardia bacteria, Skermania bacteria, Willamdia bacteria, and Mycobacterium bacteria. 11. The method according to claim 10, which is at least one selected from the group. General formula (1):

A compound represented by, a prodrug thereof, a salt thereof, or a solvate thereof.

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