JP2011037730A - Dna synthase inhibitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To find out a compound exhibiting a DNA synthase-inhibiting action and to provide new pharmaceutical compositions (a DNA synthase inhibitor, an anticancer agent and an anti-inflammatory agent) utilizing the compound. <P>SOLUTION: A compound represented by general formula (1) or (2) (wherein R is H or an alkyl group), and a pharmacologically acceptable salt thereof are provided. The pharmaceutical compositions (the DNA synthase inhibitor, the anticancer agent, the anti-inflammatory agent and the like) comprise the compound or a salt thereof as an effective ingredient. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a compound having a DNA synthase inhibitory action and use thereof. This compound can be used as a DNA synthase inhibitor, for example, as a biochemical reagent, or as an anticancer agent, an anti-inflammatory agent, or a lead compound thereof.

  Eukaryotic DNA synthases (DNA polymerases) are α, β, γ, δ, ε, ζ, η, θ, ι, κ, λ, μ, σ and TdT (terminal deoxynucleotidyl transferase). ), 15 molecular species of Rev1 are known. These DNA synthase groups are involved in cell growth, division, differentiation, etc., but α type is DNA replication, β type, λ type and TdT are repair and recombination, and δ type and ε type are replication. It is known that the ζ to κ types have different functions depending on the type, such as both repair and ζ to κ.

  Since DNA synthase is involved in cell growth and the like in this way, a DNA synthase inhibitor that inhibits the enzyme activity exhibits, for example, cancer cell growth inhibitory action against cancer and HIV against AIDS. It is considered that it exhibits an inhibitory effect on the derived reverse transcriptase and an immunosuppressive action that suppresses specific antibody production against an antigen against an immune disease. For this reason, development of pharmaceuticals effective for prevention and treatment of cancer diseases, viral diseases such as AIDS, and immune diseases using a DNA synthase inhibitor is expected.

  For example, it has been reported that glycolipids having DNA synthase inhibitory activity are useful as anticancer agents, HIV-derived reverse transcriptase inhibitors, and immunosuppressants (see Patent Document 1 below). Currently, dideoxy TTP (ddTTP), N-methylmaleimide, butylphenyl-dGTP, and the like are known as DNA synthetase inhibitors (see Non-Patent Document 1 below). In addition, sulfosynovosyl acylglycerides, which are plant-derived glycolipids, have been found to inhibit DNA synthase (see Patent Document 2 below).

  By the way, conventional anticancer agents have killed many cancer cells and have cancer cell growth-inhibiting action, but in recent years, development of anticancer agents for the purpose of preventing carcinogenesis has also been promoted. .

  In this regard, as described in Patent Document 3, “initiator” and “promoter” are related in the step of canceration of normal cells, and canceration of normal cells is “(1) normal cells. Carcinogenesis that occurs through two steps: "2) the chromosomes of 2 are damaged by the initiator at the DNA level and are changed into potential tumor cells. (2) Promoters act on the potential tumor cells and change into tumor cells." The two-stage theory is becoming common.

  TPA (12-O-Tetradecanoylphorbol-13-acetate) and the like are known as representatives of compounds having an action as a carcinogenic promoter, and carcinogenic experiments using such carcinogenic promoters are conducted in the field of cancer research. In the search for carcinogenesis prevention and anti-carcinogenic agents, the search for anti-tumor promoters that inhibit the action of such tumor promoters is ongoing.

JP 11-106395 A JP 2000-143516 A JP-A-9-176184

Annual Review of Biochemistry, 2002, 71, 133-163

  An object of the present invention is to find a novel compound having a DNA synthase inhibitory action and to provide a new pharmaceutical composition (DNA synthase inhibitor, anticancer agent and anti-inflammatory agent) using the compound.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have obtained a novel compound 1 (“trichoderonic” from a culture solution obtained by culturing Trichoderma virens in a PDB medium (potato dextrose liquid medium). acid A ") and compound 2 (named" trichoderonic acid B ") were isolated (see Example 1).

  The present inventor investigated and examined the relationship between these compounds and the DNA synthase inhibitory action, anti-inflammatory action and anti-carcinogenic action. It was confirmed to inhibit selectively. The inventors have also found that these compounds have an anti-inflammatory effect. As a result of further research based on this knowledge, the present invention has been completed.

  That is, the present invention provides the following compounds, DNA synthase inhibitors, anticancer agents and anti-inflammatory agents containing the compounds as active ingredients.

  Item 1 A compound represented by the general formula (1) or (2) or a pharmaceutically acceptable salt thereof.

(In the formula, R represents H or an alkyl group.)
Item 2 A pharmaceutical composition comprising the compound represented by the general formula (1) or (2) according to Item 1 or a pharmaceutically acceptable salt thereof as an active ingredient.

  Item 3. A DNA synthase inhibitor comprising, as an active ingredient, the compound represented by the general formula (1) or (2) according to Item 1 or a pharmaceutically acceptable salt thereof.

  Item 4 An anticancer agent comprising the compound represented by the general formula (1) or (2) according to Item 1 or a pharmaceutically acceptable salt thereof as an active ingredient.

  Item 5. An anti-inflammatory agent comprising, as an active ingredient, the compound represented by the general formula (1) or (2) according to Item 1 or a pharmaceutically acceptable salt thereof.

  Item 6 An edible composition comprising the compound represented by the general formula (1) or (2) according to Item 1 or a pharmaceutically acceptable salt thereof in a food.

  The novel compound 1 (trichoderonic acid A), compound 2 (trichoderonic acid B), and derivatives thereof of the present invention have a DNA synthase inhibitory action. In particular, Compound 2 selectively inhibits DNA synthases β, λ and TdT belonging to the X family among mammalian DNA synthases.

  In addition, since compound 2 suppresses inflammation induced by TPA in a dose-dependent manner, it has an anti-tumor promoter activity that suppresses the action of the tumor promoter TPA.

  Therefore, these compounds can be used as pharmaceutical compositions such as DNA synthase inhibitors, anticancer agents, anti-inflammatory agents and the like.

  These compounds can also be used as biochemical reagents by utilizing the above-mentioned activity. Furthermore, these compounds can be blended into foods and used as edible compositions.

The process of isolation and purification of compounds 1 and 2 from Trichoderma virens culture by silica gel column chromatography is shown. 2 is a chemical structure of Compound 1. ¹ H-NMR and ¹³ C-NMR data of Compound 1. 2 is a chemical structure of Compound 2. ¹ H-NMR and ¹³ C-NMR data of Compound 2. It is an inhibition curve for DNA synthase α, β and λ of compound 2 (trichoderonic acid B). It is a graph which shows the inhibitory effect with respect to a DNA metabolic system enzyme in 100 micromol of compound 2 (trichoderonic acid B). It is a graph which shows the cell growth effect with respect to (A) HeLa cell and (B) MCF-7 cell of the compound 1 (trichoderonic acid A). It is a graph which shows the cell growth effect by (A) HeLa cell and (B) MCF-7 cell of compound 2 (trichoderonic acid B).

  Hereinafter, the present invention will be described in detail.

1. Compound of the present invention and isolation / purification thereof The present invention relates to a compound represented by the general formula (1) or (2) or a pharmaceutically acceptable salt thereof.

(In the formula, R represents H or an alkyl group.)
In the compounds represented by the general formulas (1) and (2), examples of the alkyl group represented by R include a chain, branched, or cyclic alkyl group having 1 to 10 carbon atoms. Specific examples include alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, pentyl, cyclopentyl, hexyl and cyclohexyl.

The compounds represented by the general formulas (1) and (2) have a plurality of asymmetric carbons (sp ³ carbons), and the compound has a stereostructure of a plurality of asymmetric carbons of either R or S. Are also included. For example, any of enantiomers, diastereomers, and mixtures thereof are included.

  Among the compounds represented by the general formula (1), compound 1 (trichoderonic acid A) in which R is H is preferable. Of the compounds represented by general formula (2), compound 2 (trichoderonic acid B) in which R is H is preferable.

  Examples of the salt of “pharmaceutically acceptable salt thereof” in the present invention include alkali metal salts such as sodium salt and potassium salt; ammonium salt; primary, secondary or tertiary amine salt; quaternary ammonium salt; amino acid Examples include salt. The compound represented by the general formulas (1) and (2) or a pharmaceutically acceptable salt thereof may be a solvate such as water.

  Among the compounds represented by the general formulas (1) and (2), a compound represented by R = H is a strain of Trichoderma virens (FERM S-10, ATCC 9645, CBS 430.54, IFO 6355, IMI 45553ii, QM). 365, NBRC 6347) can be isolated and purified from the culture obtained. Specifically, Trichoderma bilens is statically cultured in a PDB medium (potato dextrose liquid medium), and the filtrate obtained by removing the cells from the culture is extracted with a solvent. Examples of the extraction solvent include alcohols such as methanol, ethanol, propanol and butanol, glycols such as 1,3-butylene glycol, glycerin and propylene glycol, esters such as ethyl acetate and butyl acetate, ethyl ether and propyl ether. Polar organic solvents such as ethers such as isopropyl ether, tetrahydrofuran and dioxane, halogenated hydrocarbons such as methylene chloride and chloroform; non-polar organic solvents such as hexane, cyclohexane and petroleum ether, etc. It can also be used alone or as a mixed solvent of two or more.

  Among these, it is preferable to use at least one extraction solvent selected from the group consisting of halogenated hydrocarbons such as methylene chloride, alcohols such as methanol and ethanol, and esters such as ethyl acetate. When mixing and using a solvent, what is necessary is just to adjust the mixing ratio of each solvent suitably according to the kind of solvent.

  After obtaining the extract by the above method, it is obtained by solvent fractionation operation using one or more organic solvents such as methanol, ethanol, propanol, butanol, chloroform, ethyl acetate, toluene, hexane, benzene and the like. The active fraction (compounds 1 and 2) can be separated from the extracted liquid. Furthermore, it can also be purified by combining one or more suitable separation and purification means such as alumina column chromatography, silica gel chromatography, gel filtration chromatography, ion exchange chromatography, hydrophobic chromatography, and high performance liquid chromatography. . In addition, isolation and identification of the active compound from the culture solution can be performed specifically as described in Example 1.

  Further, R = alkyl among the compounds represented by the general formulas (1) and (2) is obtained by esterifying the carboxylic acid moiety of the isolated compound 1 or 2 by a known method using a predetermined alcohol. Can be obtained.

2. Use of the compound of the present invention The compound represented by the general formula (1) or (2) of the present invention has a DNA synthase selective inhibitory action, and thus can be used for pharmaceuticals. For example, it is useful as a pharmaceutical composition such as a DNA synthase selective inhibitor, an anticancer agent, and an anti-inflammatory agent. The compound of the present invention can also be used as a lead compound in the pharmaceutical development process.

  When the compound of the present invention is administered into the body, parenteral administration is preferred over oral administration, and administration in a carrier such as a liposome is preferred. At this time, if a carrier that specifically recognizes cancer cells is used, the compound of the present invention can be efficiently transported to the target site (lesion site).

  Next, a pharmaceutical composition comprising the compound of the present invention will be described. The anticancer agent and anti-inflammatory agent containing the compound of the present invention as an active ingredient can be administered to animals and humans as they are or as a pharmaceutical composition together with a conventional pharmaceutical preparation carrier. The dosage form of the pharmaceutical composition is not particularly limited and may be appropriately selected as necessary.For example, oral preparations such as tablets, capsules, granules, fine granules, powders, injections, Non-oral preparations such as suppositories are mentioned, and preferred examples include parenteral preparations.

  In the present invention, oral preparations such as tablets, capsules, granules, fine granules, and powders are produced according to a conventional method using, for example, starch, lactose, sucrose, mannitol, carboxymethylcellulose, corn starch, inorganic salts, and the like. . The compounding amount of the compound of the present invention in these preparations is not particularly limited and can be appropriately designed. In addition to the compound of the present invention, a binder, a disintegrant, a surfactant, a lubricant, a fluidity promoter, a corrigent, a colorant, a fragrance and the like can be appropriately used for this type of preparation.

  Examples of the binder include starch, dextrin, gum arabic powder, gelatin, hydroxypropyl starch, sodium methylcellulose, hydroxypropylcellulose, crystalline cellulose, ethylcellulose, polyvinylpyrrolidone, macrogol and the like. Examples of the disintegrant include starch, hydroxypropyl starch, carboxymethylcellulose sodium, carboxymethylcellulose calcium, carboxymethylcellulose, and low-substituted hydroxypropylcellulose. Examples of the surfactant include sodium lauryl sulfate, soybean lecithin, sucrose fatty acid ester, polyoxyethylene sorbitan fatty acid ester and the like. Examples of lubricants include talc, waxes, hydrogenated vegetable oils, sucrose fatty acid esters, magnesium stearate, calcium stearate, aluminum stearate, polyethylene glycol and the like. Examples of the fluidity promoter include light anhydrous silicic acid, dry aluminum hydroxide gel, synthetic aluminum silicate, magnesium silicate and the like. The compounds of the present invention can also be administered as suspensions, emulsions, syrups, and elixirs, and these various dosage forms may contain flavoring agents and colorants.

  In order to express the desired effect of the present invention as a parenteral agent, it varies depending on the age, body weight, and degree of disease of the patient, but usually, 1 to 60 mg intravenously per day as the weight of the compound of the present invention in an adult, Intravenous infusion, subcutaneous injection, and intramuscular injection are suitable. This parenteral preparation is produced according to a conventional method, and generally used as diluent is distilled water for injection, physiological saline, aqueous glucose solution, vegetable oil for injection, sesame oil, peanut oil, soybean oil, corn oil, propylene glycol, etc. it can. Furthermore, you may add a disinfectant, antiseptic | preservative, and a stabilizer as needed. In addition, from the viewpoint of stability, this parenteral preparation can be frozen after filling into a vial or the like, the water can be removed by ordinary freeze-drying treatment, and the liquid preparation can be re-prepared from the freeze-dried product immediately before use. Furthermore, you may add an isotonic agent, a stabilizer, an antiseptic | preservative, and a soothing agent as needed. The compounding quantity of the compound of this invention in these formulations is not specifically limited, It can set arbitrarily. Examples of other parenteral agents include liquid preparations for external use, coating agents such as ointments, suppositories for rectal administration, etc., and these are also produced according to conventional methods.

  Moreover, the compound of this invention can be utilized for food other than the utilization to a pharmaceutical. For example, it can be used as an edible composition (for example, health food) having an anti-cancer effect, an anti-carcinogenic effect, or an anti-inflammatory effect by adding and blending with food and drink.

  That is, the compound of the present invention is used as it is in a liquid, gel or solid food such as juice, soft drink, tea, soup, soy milk, salad oil, dressing, yogurt, jelly, pudding, sprinkle, infant formula, cake. Add to mixes, powdered or liquid dairy products, bread, cookies, etc., and if necessary, process into pellets, tablets, granules etc. with excipients such as dextrin, lactose, starch, flavorings, pigments, etc. Further, it can be coated with gelatin or the like and molded into a capsule to be used as a health food or nutritional supplement.

  Since the DNA synthase structure of humans and other mammals is almost the same, the DNA synthase inhibitor of the present invention can be used as a DNA synthase inhibitor derived from mammals other than humans.

  Further, as described above, there is a correlation between the DNA synthase inhibitory action, the anti-inflammatory action and the anticarcinogenic action, and the compound 2 that specifically inhibits the DNA synthase is chronically induced by TPA. Inflammation was suppressed. This result indicates the possibility that DNA synthase plays an important role in the development of chronic inflammation due to TPA. TPA not only induces chronic inflammation but also promotes cell growth in mammals as an oncogenic promoter. Compound 1 and Compound 2, which are selective inhibitors of DNA synthase, exhibit an anti-carcinogenic action that suppresses the action of such tumor promoter TPA.

  Therefore, efficient screening of candidate compounds for anticancer agents or anti-inflammatory agents can be expected by examining the inhibitory activity against DNA synthase using the compound of the present invention as a lead. The present invention includes such a screening method. In this screening method, the method for examining the inhibitory activity against DNA synthase is not limited to the method described in the above-mentioned Examples, and a suitable method may be selected from known test methods.

  Next, the present invention will be specifically described, but the present invention is not limited thereto.

Example 1
(1) Isolation and culture of strains The petals collected at Inage Seaside Park were cultured on PDA medium (potato dextrose agar medium) to isolate this strain (referred to as IG34HB strain for convenience). As a result of strain identification, this strain was identified as Trichoderma virens (FERM S-10, ATCC 9645, CBS 430.54, IFO 6355, IMI 45553ii, QM 365, NBRC 6347). This strain was statically cultured for 26 days in six 2 L Erlenmeyer flasks (total 6 L) containing 1 L of PDB medium (potato dextrose liquid medium).

(2) Extraction and purification The culture solution obtained by culturing the present strain was removed from the cells using gauze. The obtained filtrate was extracted with methylene chloride, and the solvent was distilled off using a rotary evaporator to obtain a crude extract (932 mg). As shown in FIG. 1, this crude extract was subjected to column chromatography using silica gel as a carrier and chloroform-methanol (100: 0 → 0: 100) as a developing solvent, so that six fractions (Fr. A to Fr. F) were obtained. It was fractionated.

  Fr. D (566.7 mg) eluted with chloroform-methanol (80: 1-40: 1) was obtained by column chromatography using silica gel as a carrier and dichloromethane-methanol (100: 0 → 0: 100) as a developing solvent. Fractions were fractionated into 4 fractions (Fr.DA to Fr.DD).

  Fr.DD (40.4 mg) eluted with dichloromethane-methanol (0: 100) is a column using silica gel as a carrier and toluene-ethyl acetate (8: 1 to 2: 1) containing 1% acetic acid as a developing solvent. It was fractionated into 7 fractions (Fr.DDA to Fr.DDG) by chromatography. Compound 1 (4.8 mg) was eluted with 1% acetic acid in toluene-ethyl acetate (4: 1) from Fr. DDC eluted with 1% acetic acid in toluene-ethyl acetate (6: 1). Compound 2 (10.5 mg) was obtained from Fr. DDF.

(3) Structure determination The structures of Compound 1 and Compound 2 were determined by MS, IR, ¹ H-NMR, ¹³ C-NMR, DEPT, ¹ H- ¹ H COZY, HMQC, and HMBC. Carbon number of the compound 1 in FIG. 2 (A), exhibited ¹ H- ¹ H COZY, HMBC correlations of Compound 1 in (B). FIG. 3 shows ¹ H-NMR and ¹³ C-NMR data of Compound 1 measured in CDCl ₃ . 4A shows the carbon number of Compound 2, and FIG. 4B shows the ¹ H- ¹ H COZY and HMBC correlation of Compound 2. FIG. 5 shows ¹ H-NMR and ¹³ C-NMR data of Compound 2 measured in CDCl ₃ .

Various properties and spectrum data (excluding NMR data) of Compound 1 are as follows. Colorless oil, [α] _D ²⁶ +5.9 (c 0.56, CHCl ₃ ); IR ν _max (film): 3434, 2958, 1705, 1241, 1104, 775 cm ^-1 (KBr); HR-ESIMS m / z found 335.1463 [M + Na] ⁺ (calculated value C ₁₆ H ₂₄ O ₆ Na 335.1465)
Various properties and spectral data (excluding NMR data) of Compound 2 are as follows. Colorless oil, [α] _D ²⁶ -22.3 (c 0.09, CHCl ₃ ); IR ν _max (film): 2960, 1743, 1716, 1238, 1058, 756, 463 cm ^-1 (KBr); HR-ESIMS m / z found 583.2509 [M + Na] ⁺ (calculated value C ₃₀ H ₄₀ O ₁₀ Na 583.2513)

Compound 1, MS, ¹ H-NMR, ¹³ C-NMR and DEPT were shown to have the molecular formula C ₁₆ H ₂₄ O ₆ . First, the ¹ H- ¹ H COZY correlation suggested the existence of the partial structure shown in bold lines in FIG. In addition, the presence of cyclohexane structure was suggested by the HMBC correlation of H-5, H-9 → C-6. The chemical shift of C-4 suggests the presence of carbonyl, and the HMBC correlation of H-3 → C-2, C-4, C-13 and H-5 → C-4, C-12, C-13. HMBC correlation and H-12 → C-2, C-5, C-13 HMBC correlation suggested the existence of unsaturated 7-membered lactone. The chemical shift of Me-8 suggests the presence of a methoxy group, and the HMBC correlation from H-8 → C-7 and the correlation from H-7 → C-5, C-6, C-9 to methoxymethyl at C-6 Was suggested to be bound. Finally, the chemical shift of 2958 cm ^-1 and C-1 in the IR spectrum suggests the presence of carboxylic acid, and the HMBC correlation of H-3, H-13 → C-1 indicates that C-1 carboxylic acid is C-2 It was suggested that it is bound to.

  From the above, compound 1 is 9-hydroxy-6-isopropyl-9- (methoxymethyl) -1-oxo-1,3,5a, 6,7,8,9,9a-octahydro-2-benzoxepin-4-carbon Acid (9-hydroxy-6-isopropyl-9- (methoxymethyl) -1-oxo-1,3,5a, 6,7,8,9,9a-octahydro-2-benzoxepine-4-carboxylic acid) (tricoderonic acid) A; named trichoderonic acid A).

Compound 2, MS, ¹ H-NMR, ¹³ C-NMR and DEPT were shown to have the molecular formula C ₃₀ H ₄₀ O ₁₀ . The NMR data of Compound 2 was similar to that of trichoderonic acid A (Compound 1) except for C-7, C16, C-20, C-21 and C-22. The HHM → C-16 HMBC correlation suggested a structure in which a similar structure of tricoderonic acid A was dimerized. For C-21 and C-22, epoxide was present at C-21 and C-22 from chemical shift and coupling constant J _21,22 = 5.2 Hz. From the above, compound 2 was obtained by using 9-hydroxy-6-isopropyl-9 ((6-isopropyl-1-oxo-1,3,5a, 6,7,9a-hexahydro-3H-spiro [2-benzoxepin-9,2 '-Oxirane] -4-ylcarbonyloxy) methyl) -1-oxo-1,3,5a, 6,7,8,9,9a-octahydro-2-benzoxepin-4-carboxylic acid (9-hydroxy-6 -isopropyl-9 ((6-isopropyl-1-oxo-1,3,5a, 6,7,9a-hexahydro-3H-spiro [2-benzoxepine-9,2'-oxirane] -4-ylcarbonyloxy) methyl) -1-oxo-1,3,5a, 6,7,8,9,9a-octahydro-2-benzoxepine-4-carboxylic acid) (named tricoderonic acid A).

Example 2 (Verification of DNA synthase inhibitory activity)
The activity of the compound 1 (trichoderonic acid A) and compound 2 (trichoderonic acid B) obtained in the above examples against the DNA synthase group was measured by the following method.

  Tests were conducted on mammalian DNA synthases α, β and λ as DNA synthases. DNA synthase α is a sample extracted and purified from bovine thymus by a conventional method, DNA synthase β is a rat-derived gene, DNA synthase λ is a human-derived gene, and a conventional gene recombination method is used. The preparations incorporated into Escherichia coli and produced were used. TdT was purchased from Takara Bio Inc. and used as a reagent (product code: 2230A) incorporated into Escherichia coli by a genetic recombination method derived from calves.

For the measurement of the inhibitory action of compounds 1 and 2 on these DNA synthases, a general DNA synthase reaction system (edited by the Japanese Biochemical Society, Shinsei Chemistry Laboratory 2, Nucleic Acid IV, Tokyo Kagaku Dojin, pages 63-66) Was used. That is, a DNA synthesis reaction is carried out in a system containing [ ³ H] -TTP labeled with a radioisotope, and the radioactivity is used as an index of the amount of product (synthetic DNA chain).

The inhibition rate is (a) the amount of synthetic DNA in the control, and (b) the amount of synthetic DNA in the presence of the test substance.
(a-b) / a × 100 = inhibition rate (%)
As evaluated. The results obtained are shown in Table 1 as 50% inhibitory concentration (μM).

  As shown in Table 1, Compound 1 selectively inhibited DNA synthase λ, and Compound 2 selectively inhibited DNA synthase β, λ and TdT. The inhibitory activity of Compound 2 was more than 10 times stronger than that of Compound 1. FIG. 6 shows inhibition curves of Compound 2 against DNA synthases β, λ and TdT.

  Compound 2 was found to inhibit DNA synthase λ most strongly, β-type second, and TdT third. As a result of calculating the inhibition mode of Compound 2 against DNA synthase λ from the reciprocal plot of Lineweaver-Burk, it was non-competitive inhibition with respect to two substrates, template DNA and nucleotide (dNTP) (data not shown).

  DNA synthase has a high enzyme activity against cells and tissues such as cancer cells that have a high cell division. Therefore, compounds 1 and 2 are expected to have an action as an anticancer agent. As shown in FIG. 7 (A), mammalian DNA synthases are classified into four families of A, B, X, and Y based on the homology of their gene sequences and differences in activity functions. Compound 2 selectively inhibited DNA synthases β, λ and TdT belonging to the X family. On the other hand, DNA synthase γ belonging to the A family, DNA synthase α, δ, ε belonging to the B family, and DNA synthases η, ι, κ belonging to the Y family were not inhibited.

  Similarly, DNA synthases derived from fish, plants and prokaryotes other than mammals were investigated, but Compound 2 did not inhibit (FIG. 7B). Furthermore, DNA metabolic enzymes other than DNA synthase were also investigated, but Compound 2 did not have an inhibitory action (FIG. 7 (C)). From these results, it was found that Compound 2 selectively inhibits mammalian DNA synthase / X family.

Example 3 (Verification of cell growth inhibitory activity)
The cancer cell proliferation inhibitory effect of compound 1 (trichoderonic acid A) and compound 2 (trichoderonic acid B) was evaluated using the following method.

The cells used in this experiment are human cervical cancer-derived HeLa cells and human breast cancer-derived MCF-7 cells. The medium used was DMEM medium (Nippon Pharmaceutical Co., Ltd.) supplemented with fetal bovine serum 10% (v / v) and penicillin-streptomycin 5% (v / v). Culturing was performed at 37 ° C. with 5% CO ₂ incubation.

  Compounds 1 and 2 were dissolved in the medium shown above so as to obtain each test concentration in advance. However, since compounds 1 and 2 are hardly soluble in water, they were once dissolved in DMSO (dimethyl sulfoxide) and dissolved in the above medium. The final concentration of DMSO present in the medium is 0.1% in all test groups, and the possibility that DMSO is involved in the suppression of the growth of each cell used in this measurement example can be denied.

The culture for this experiment was performed in a 96-well microplate. Each well was implanted with 5.0 × 10 ³ cells and given 3 wells for one test concentration. Each cell was cultured in a plate for 24 hours, and after addition of each concentration of compounds 1 and 2, the cells were cultured for 48 hours at 37 ° C in 5% CO ₂ incubation, and the cell viability of each test group was determined. . Viability was determined using the living cell count reagent SF (performed by the method of Talanta 1997, 44). The novel tetrazolium salt WST-8 contained in the living cell measurement reagent SF is reduced by intracellular dehydrogenase to produce a highly sensitive water-soluble formazan, which is easily produced by directly measuring the absorbance of this formazan at 450 nm. The number of cells can be measured. Therefore, in this experiment, after culturing for 48 hours, the living cell number measuring reagent SF was added, and after further culturing for 2 hours, the absorbance (OD) at 450 nm was measured, and the cell viability was calculated by the following formula.

  The obtained results are shown in FIGS. The data shown in FIGS. 8 and 9 is an average of 3 wells.

Compound 1 did not inhibit the growth of each cancer cell, but Compound 2 inhibited the growth of each cancer cell. From the results of FIGS. 8 and 9, the 50% growth inhibitory concentration (IC ₅₀ ) of Compound 2 was 15.6 μM in HeLa cells and 8.7 μM in MCF-7 cells. From this result, it was shown that Compound 2, which specifically inhibits DNA synthase, actually exhibits a cell growth inhibitory effect on human cancer cell lines and can be used as an anticancer agent.

Example 4 (Verification of anti-inflammatory and anti-carcinogenic effects)
TPA (12-O-tetradecanoylphorbol-13-acetate) not only induces chronic inflammation but also promotes cell growth in mammals as an oncogenic promoter. The present inventor believes that DNA synthase inhibitory activity (particularly DNA synthase λ inhibitory activity involved in DNA repair / recombination), anti-inflammatory activity and anti-tumor promoter activity are mutually related. Thought. Therefore, it was examined whether Compound 1 (trichoderonic acid A) and Compound 2 (trichoderonic acid B) have anti-inflammatory activity. The results are shown in Table 2 below.

  In the experiment, each inhibitory effect was calculated by measuring the weight of inflammatory edema induced by TPA after applying a predetermined amount of Compound 1 or Compound 2 to the mouse ear in advance. The test is basically performed according to the method described in Cancer Lett. 1984, 25, pp. 177-85, and 250 μg or 500 μg of the compound is applied to one ear of a mouse, and 30 minutes later, the same part and the opposite ear are applied. Apply 0.5 μg of TPA. After 7 hours, the weight of inflammatory edema induced by TPA was measured, and each inhibitory effect was calculated by comparing with the control (opposite ear).

  As shown in Table 2, Compound 2 inhibited inflammation depending on the application amount of 250 μg and 500 μg. From this experimental result, Compound 2 was recognized as having an anti-inflammatory effect. Further, from this experimental result, it was recognized that Compound 2 has an anti-carcinogenic promoter activity (in other words, an anti-carcinogenic effect) that suppresses the action of the oncogenic promoter TPA.

Claims (6)

A compound represented by the general formula (1) or (2) or a pharmaceutically acceptable salt thereof.

(In the formula, R represents H or an alkyl group.) A pharmaceutical composition comprising the compound represented by the general formula (1) or (2) according to claim 1 or a pharmaceutically acceptable salt thereof as an active ingredient. A DNA synthase inhibitor comprising the compound represented by the general formula (1) or (2) according to claim 1 or a pharmaceutically acceptable salt thereof as an active ingredient. An anticancer agent comprising the compound represented by the general formula (1) or (2) according to claim 1 or a pharmaceutically acceptable salt thereof as an active ingredient. An anti-inflammatory agent comprising the compound represented by the general formula (1) or (2) according to claim 1 or a pharmaceutically acceptable salt thereof as an active ingredient. An edible composition comprising the compound represented by the general formula (1) or (2) according to claim 1 or a pharmaceutically acceptable salt thereof in a food.

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