JPH0723308B2 - Radiosensitizer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a radiosensitizer, and more particularly, to a radiosensitizer for a non-curative hypoxic cell present in a malignant tumor, which contains a specific nitrotriazole compound as an active ingredient. It relates to a radiosensitizer that promotes activation.

Conventionally, radiation therapy, surgery, chemotherapy, immunotherapy, etc. have been used as treatments for malignant tumors. Among them, radiation therapy is an effective treatment that has been used for many years. is there.

However, there is a problem that the radiation treatment may not cure the tumor and that the tumor may recur even if it is once cured.

This may be due to the presence of radioresistant cells of the tumor tissue itself and oxygen-deficient radioresistant cells in the tumor. In fact, in the irradiation experiment,
It is known that cells in an atmosphere in which oxygen is excluded are 2-3 times more resistant to radiation than cells in the presence of oxygen.

Under such circumstances, there has been a strong demand for the development of a hypoxic cell sensitizer as a drug for enhancing the sensitivity of hypoxic cells to radiation as an extremely effective means for improving the radiotherapy effect.

From such a viewpoint, some hypoxic cell sensitizers have been conventionally developed, and, for example, nitroimidazole derivatives are known as typical ones.

However, misonidazole, which is one of the typical compounds of nitroimidazole derivative, shows a sensitizing effect about twice as much as that in the case of no addition in animal transplant tumor experiments, but it is difficult to administer in large amounts because of its neurotoxicity. No sensitizing effect has been observed from the results of application to humans at applicable doses.

The inventors of the present invention have conducted extensive studies to find a compound having low toxicity and a higher sensitizing effect, and as a result, the following general formula (I) 3-nitro-1,2,4-triazole compound was found to be a hypoxic cell. It has been found that the sensitivity of radix to radiation can be significantly increased and the effect of radiotherapy can be increased.

(In the formula, X represents a halogen atom or —CO—R ₁ , R ₁ represents —O—R ₂ or —N (R ₃ ) R ₄ , R ₂ represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, An alkyl group having an ether bond or a hydroxyl group and an alkyl group having an ether bond are shown, R ₃ is a hydrogen atom, an alkyl group, a hydroxyalkyl group or an alkyl group having an ether bond, and R ₄ is represented by R _3. Group, or -R ₅ -N
(R ₆ ) R ₇ is shown, R ₅ is an alkylene group, and R ₆ and R ₇ are
A group represented by R _3, also, R ₃ and R ₄ or R ₆ and R ₇ may be an alkylene group or an oxa dialkylene group bonded to each other, further R ₃ and R ₆ are bonded to each other And may represent an alkylene group.

R is a hydrogen atom, an alkyl group, a hydroxyalkyl group, _{-CH 2 -CH (OH) -CH 2} -Y or indicates _{R 8 -CO-R 1, R} 8
Represents an alkylene group, Y represents —O—R ₂ or —N (R ₃ ) —
Indicates R ₄ . ) Hereinafter, the nitrotriazole compound having a specific substituent of the present invention will be described in detail.

In the above compound, as the alkyl group, methyl, ethyl, propyl, isopropyl, butyl, isobutyl,
Secondary butyl, amyl, hexyl, heptyl, octyl,
Examples thereof include isooctyl and 2-ethylhexyl, and the hydroxyalkyl group includes 2-hydroxyethyl and 2
-Hydroxypropyl and the like, examples of the alkyl group having an ether bond include methoxyethyl, ethoxyethyl, butoxyethyl, ethoxyethoxyethyl and the like, and examples of the alkyl group having a hydroxyl and ether bond include 2- (2 ' -Hydroxyethoxy) ethyl and the like.

Examples of the alkylene group include methylene, ethylene, trimethylene, 1,2-propylene, tetramethylene, pentamethylene, 1,5-hexylene, 2,6-heptylene, hexamethylene and the like.

Examples of the oxadialkylene group include oxadiethylene and the like.

Accordingly, the compound represented by the above general formula of the present invention is 2- (3'-nitro-5'-bromo-1 ', 2', 4 '.
-Triazol-1'-yl) acetic acid ethanolamide,
2- (3'-nitro-5'-bromo-1 ', 2', 4'-triazol-1'-yl) acetic acid diethanolamide, 2
-(3'-Nitro-5'-bromo-1 ', 2', 4'-triazol-1'-yl) acetic acid methoxyethylamide, 1
-(3'-methoxy-2'-hydroxypropyl) -3
-Nitro-5-bromo-1,2,4-triazole, methyl 1-methyl-3-nitro-1,2,4-triazole-5-carboxylate, 3-nitro-1,2,4-triazole-5 −
Carboxylic acid methoxyethylamide, 1-methoxycarbonylmethyl-3-nitro-1,2,4-triazole-5
Methyl carboxylate, 1- (3'-methoxy-2'-hydroxypropyl) -3-nitro-1,2,4-triazole-5-carboxylate, 1-methyl-3-nitro-1,
2,4-Triazole-5-carboxylic acid ethanolamide, 1- (2 ', 3'-epoxypropyl) -3-nitro-1,2,4-triazole-5-carboxylic acid ethanolamide, 1- (3'-Methoxy-2'-hydroxypropyl) -3-nitro-1,2,4-triazole-5-carboxylic acid ethanolamide, 1- (2'-hydroxyethyl) -3-nitro-1,2,4-triazole -5-carboxylic acid ethanolamide, 1- (2'-hydroxyethylcarbamoylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid ethanolamide, 3-nitro-
1,2,4-triazole-5-carboxylic acid methoxyethylamide, 1-methoxycarbonylmethyl-3-nitro-
1,2,4-Triazole-5-carboxylic acid methoxyethylamide, 1- (2'-hydroxyethylcarbamoylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid methoxyethylamide, 1- [N, N-bis (2 '
-Hydroxyethyl) carbamoylmethyl] -3-nitro-1,2,4-triazole-5-carboxylic acid methoxyethylamide, 1- (3'-aziridino-2'-hydroxypropyl) -3-nitro-1,2 , 4-triazole-5
-Carboxylic acid methoxyethylamide, 1- (2'-hydroxyethylcarbamoylethyl) -3-nitro-1,2,
4-triazole-5-carboxylic acid methoxyethylamide, 1- (hydroxyethoxycarbonylmethyl) -3
-Nitro-1,2,4-triazole-5-carboxylic acid methoxyethylamide, 1- (ethoxyethoxycarbonylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid methoxyethylamide, 1- (Hydroxyethoxyethoxycarbonylmethyl) -3-nitro-1,2,4
-Triazole-5-carboxylic acid methoxyethylamide, 1-methyl-3-nitro-1,2,4-triazole-
5-carboxylic acid diethanolamide, 1-methyl-3-
Nitro-1,2,4-triazole-5-carboxylic acid (2 ',
3'-dihydroxypropylamide), 1- (morpholinocarbonylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid morpholide, 1- (aziridinocarbonylmethyl) -3-nitro-1,2 , 4-Triazole-5-carboxylic acid aziridide, 1- (piperidinocarbonylmethyl) -3-nitro-1,2,4-triazole-5
-Carboxylic acid piperidide, 1- (4'-methylpiperazinocarbonylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid (4 "-methylpiperazide), 1
-(Diethylcarbamoylmethyl) -3-nitro-1,2,
4-triazole-5-carboxylic acid diethylamide, 1
-(Dimethylaminopropylcarbamoylmethyl) -3
-Nitro-1,2,4-triazole-5-carboxylic acid dimethylaminopropylamide, 1- (morpholinopropylcarbamoylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid morpholinopropylamide can give.

When these compounds have an amino group, of course, they may be acid addition salts, and examples of the acid forming the acid addition salt include hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid and the like. And inorganic acids such as acetic acid, propionic acid, oxalic acid, citric acid, tartaric acid, adipic acid, lactic acid and p-toluenesulfonic acid.

These compounds are, for example, a method of reacting a 3-nitro-1,2,4-triazole-5-carboxylic acid ester or amide with a halocarboxylic acid ester or an unsaturated carboxylic acid ester, and then, if necessary, amidation. A method of reacting epihalohydrin and then adding amines or alcohols as needed; a method of adding alkylene oxide and the like.

Next, specific production examples of the compound of the present invention will be described, but the present invention is not limited to these production examples.

Production Example 1 1-Methoxycarbonylmethyl-3-nitro-1,2,4-
Production of methyl triazole-5-carboxylate 1.1 g of methyl 3-nitro-1,2,4-triazole-5-carboxylate was dissolved in 10 ml of dimethylformamide, 280 mg of sodium hydride was added, and the mixture was stirred at room temperature for 20 minutes. Thereafter, 1.3 g of methyl bromoacetate was added, and the mixture was stirred at 60 to 70 ° C for 4 hours. The solvent was distilled off under reduced pressure, and the mixture was extracted with ethyl acetate.
Ethyl acetate was distilled off to obtain 1.1 g of a pale yellow oily product.

As a result of infrared spectroscopic analysis, it was confirmed that the substance had an absorption due to an ester at 1740 cm ⁻¹ and was a target substance.

Elemental analysis C% H% N% Calculated value 34.4 3.28 23.0 Found value 34.2 3.26 23.3 Preparation example 2 Preparation of 1- (hydroxyethylcarbamoylmethyl) -3-nitro-1,2,4-triazole-5-carboxylic acid ethanolamide 530 mg of the compound obtained in Production Example 1 was dissolved in 2 ml of dioxane, 500 mg of monoethanolamine was added, and the mixture was stirred at 70 to 80 ° C for 2 hours. After removing the solvent, it was treated with a cation exchange resin (Dowex 50w manufactured by Dow) and recrystallized from methanol / benzene to obtain colorless crystals with a melting point of 106 to 108 ° C.

IR (KBr method): 3350, 3300, 1670, 1560, 1530, 1320 and 1040 cm ^-1 Elemental analysis C% H% N% Calculated value 36.0 4.00 28.0 Measured value 35.8 3.91 27.9 Production example 3 3-Nitro-1,2, Preparation of 4-triazole-5-carboxylic acid methoxyethyl amide 1-g methyl 3-nitro-1,2,4-triazole-5-carboxylic acid was dissolved in 5 ml dioxane, methoxyethylamine 1 g was added, and at 40-50 ° C. Stir for 2 hours.

The excess amine and solvent were distilled off to give a colorless oily product.

IR: 3400, 1650, 1540 and 1120 cm ^-1 Elemental analysis C% H% N% Calculated value 33.5 4.19 32.6 Measured value 33.8 4.20 32.3 Production example 4 1-methoxycarbonylmethyl-3-nitro-1,2,4-
Production of triazole-5-carboxylic acid methoxyethylamide 1.25 g of the compound obtained in Production Example 3 was dissolved in 20 ml of dimethylformamide, and 280 mg of sodium hydride was added,
Stir for 5 minutes. Add 1.3 g of methyl bromoacetate, 60-70
The mixture was stirred at 0 ° C for 2 hours. After distilling off the solvent, the mixture was extracted with chloroform, and the chloroform was distilled off to obtain 1 g of a pale yellow oily product.
Got

IR: 3350, 1750, 1690, 1560, 1320, 1230 and 1130 cm ^-1 Elemental analysis C% H% N% Calculated value 37.6 4.53 24.4 Measured value 37.8 4.55 24.7 Preparation example 5 1- [N, N-bis (hydroxyethyl) Preparation of carbamoylmethyl] -3-nitro-1,2,4-triazole-5-carboxylic acid methoxyethylamide 530 mg of the compound obtained in Preparation Example 4 was dissolved in 3 ml of dioxane, 1 g of diethanolamine was added, and at 70-80 ° C. Stir for 2 hours. After dioxane was distilled off, the residue was treated with a cation exchange resin (Dowex 50w, manufactured by Dow) and purified by silica gel chromatography using chloroform / methanol as a developing solvent to obtain 380 mg of a colorless oily product.

IR: 3300-3450, 1650, 1550, 1310, 1120 and 1070 cm ^-1 Elemental analysis C% H% N% Calculated value 40.0 5.56 23.3 Measured value 40.4 5.48 23.1 Production example 6 1-Methyl-3-nitro-1,2, 4-triazole-5-
Production of carboxylic acid diethanolamide 1-methyl-3-nitro-1,2,4-triazole-5
470 mg of methyl carboxylate was dissolved in 3 ml of dioxane, and 300 mg of diethanolamine was added. After stirring at 60 to 70 ° C for 2 hours, dioxane was distilled off, treated with an ion exchange resin (Dowex 50w, manufactured by Dow), and recrystallized from methanol / benzene to obtain a colorless solid product having a melting point of 111 to 113 ° C. Got

IR (KBr method): 3300, 1660, 1560, 1310 and 1040 cm ^-1 Elemental analysis C% H% N% Calculated value 37.1 5.02 27.0 Measured value 37.4 5.10 26.8 Production example 7 1-Methyl-3-nitro-1,2, 4-triazole-5-
Production of Carboxylic Acid Monoethanolamide A colorless solid product having a melting point of 108 to 111 ° C. was obtained in the same manner as in Production Example 6 except that monoethanolamine was used instead of diethanolamine.

IR (KBr method): 3450, 3250, 1690, 1560, 1310 and 1080c
m ^- Elemental analysis C% H% N% Calculated value 33.5 4.19 32.6 Measured value 33.1 4.12 32.9 Production example 8 1-Methyl-3-nitro-1,2,4-triazole-5-
Production of carboxylic acid-2,3-dihydroxypropylamide Melting point 12 in the same manner as in Production Example 6 except that 2,3-dihydroxypropylamine was used instead of diethanolamine.
A colorless solid product was obtained at 5-126 ° C.

IR (KBr method): 3350, 1690, 1560, 1320 and 1040 cm ^- Elemental analysis C% H% N% Calculated value 34.3 4.49 28.6 Measured value 33.8 4.37 28.2 Preparation example 9 1- (3'-methoxy-2'-hydroxypropyl) ) −
Production of methyl 3-nitro-1,2,4-triazole-5-carboxylate Methyl 3-nitro-1,2,4-triazole-5-carboxylate 2 g, methylglycidol 6 ml and anhydrous potassium carbonate
0.2 g was taken and stirred at 80 ° C. for 20 minutes.

After filtration, it was concentrated under reduced pressure, and the residue was purified by silica gel chromatography using chloroform / methanol as a developing solvent to obtain 1.2 g of a colorless oily product.

IR: 3400, 1740, 1560, 1310, 1240 and 1050 cm ^-1 Elemental analysis C% H% N% Calculated value 36.9 4.62 21.5 Measured value 36.4 4.75 21.7 Production example 10 1- (3'-methoxy-2'-hydroxypropyl) −
Production of 3-nitro-1,2,4-triazole-5-carboxylic acid ethanolamide 350 mg of the compound of Production Example 9 was dissolved in 5 ml of dioxane, 500 mg of monoethanolamine was added, and the mixture was stirred at 80 to 100 ° C for 3 hours. Dioxane was distilled off, treated with a cation exchange resin (Dowex 50w, manufactured by Dow), and purified by silica gel chromatography using chloroform / methanol as a developing solvent to obtain 0.3 g of a colorless oily product.

IR: 3300 to 3400, 1675, 1555, 1310, 1120 and 1060 cm ^-1 Elemental analysis C% H% N% Calculated value 37.4 5.19 24.2 Measured value 37.1 5.12 23.9 Production example 11 1- (3'-methoxy-2'-hydroxy) Propyl)-
Production of 3-nitro-1,2,4-triazole-5-carboxylic acid diethanolamide A colorless oily product was obtained in the same manner as in Production Example 10 except that diethanolamine was used instead of monoethanolamine.

IR: 3250-3400, 1670, 1555, 1320, 1120 and 1055 cm ^-1 Elemental analysis C% H% N% Calculated value 39.6 5.71 21.0 Measured value 39.8 5.58 20.7 Production Example 12 1- (2'-hydroxyethyl) -3- Nitro-1,2,4
-Preparation of triazole-5-carboxylic acid ethanolamide 3.0 g of methyl 3-nitro-1,2,4-triazole-5-carboxylate, 1.53 g of ethylene oxide and 0.1 g of sodium methoxide were dissolved in 6 ml of methanol to give 50- 1.5 at 55 ° C
Stir for hours. After the solvent was distilled off, the residue was washed with benzene to obtain 1.94 g of a colorless solid product.

This product and 0.62 g of monoethanolamine were dissolved in 10 ml of dioxane and stirred at 80 to 100 ° C for 3 hours. Dioxane was distilled off and cation exchange resin (Dowex 50
After treatment with w), the product was purified by silica gel chromatography using chloroform / methanol as the eluent.
The product was obtained as a colorless solid at 108-110 ° C.

IR: 3400, 3250, 1670, 1555, 1320 and 1060 cm ⁻¹ Elemental analysis C% H% N% Calculated value 34.3 4.49 28.6 Measured value 34.0 4.55 28.8 The above compound of the present invention is useful as a sensitizer in radiotherapy, Although the dose varies depending on the type of tumor and compound, it is generally 20 to 10000 mg for an oral preparation, 0.5 to 10000 mg for an injection, and 20 to 10000 mg for a suppository.
The optimal dose is determined according to the type of radiation, irradiation dose, irradiation division degree, etc., based on the judgment of the doctor according to the symptoms.

In addition, there is no particular limitation on the administration form of the compound of the present invention,
As the carrier, those usually used in the pharmaceutical field can be used,
It is prepared according to the means commonly used in this field.

The radiation sensitizing effect of the compound of the present invention will be shown below by specific examples.

Example-1 In order to examine the radiation sensitizing effect on V-79 Chinese hamster cells, 100,000 V-79 cells were cultured in a monolayer on a glass dish to prepare logarithmic phase V-79 cells.

A medium solution of the test compound having a predetermined concentration was added to the petri dish, allowed to stand at 37 ° C for 60 minutes, and then placed in a closed container at room temperature,
Oxygen was eliminated by flowing nitrogen gas for 10 minutes, and X-ray irradiation was performed at a dose rate of 1.6 Gy / min.

After irradiation, the cells were washed with a phosphate buffer solution and made into single cells with trypsin. Then, a predetermined amount was put in a culture dish, 5 ml of medium was added, the mixture was cultured at 37 ° C for 7 days, washed with water after staining, and the number of generated colonies was measured.

As a comparison, a test was also conducted on a medium solution containing no compound, which was irradiated under nitrogen and irradiated in the presence of air.

A linear relationship is obtained by calculating the cell survival rate from these values and plotting the logarithm of the survival rate against the irradiation dose.

Find the intersection of this straight line and the horizontal straight line where the survival rate is 1.0, and derive the induction period dose: Dq (Gy)
The irradiation dose required to reduce to 0: D ₁₀ (Gy) was calculated.

Also, the irradiation dose (D _0.1% = Dq + 3D ₁₀ ) required to inactivate cells by 99.9% was calculated, Were determined and defined as air-based sensitization ratio (SARA number) and nitrogen-based sensitization ratio (N ₂ -based SARA number), respectively.

The results obtained are shown in Table 1.

Example-2 10 ⁵ EMT-6 tumor cells were subcutaneously inoculated into male and female Balb / C strain mice (8 weeks old, 4 mice per group) on both legs. After tumor cell inoculation,
A physiological saline solution of the test compound was intraperitoneally administered (200 mg / kg) when the tumor size reached about 1 cm in diameter, and 40 minutes later
X-rays were irradiated at 450 rad / min, and the mice were killed 5 minutes after irradiation.

After systemic sterilization with 70% ethanol, the tumor area is cut off,
The tissue was minced and mixed with 22 ml trypsin and stirred for 50 minutes at 37 ° C. Take the supernatant, count the number of cells,
Spread on a 5 cm plastic plate, add 5 ml of medium and culture in a carbon dioxide incubator. Cells that have not been irradiated with X-rays are taken out after 9 days, cells that have been irradiated with X-rays are taken out from the incubator after 10 days, The cells are fixed with methanol, the cells are stained with Giemsa stain, and the number of generated colonies is counted.

The cells not irradiated with X-ray were used as a control, and the survival rate was measured. The results are shown in Table-2.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Tsuneo Tsubakimoto 2-10-4 Shinsenrikitamachi, Toyonaka City, Osaka Prefecture (72) Inventor Ryoichi Okuhai 3-19-7 Shindo, Ibaraki City, Osaka Prefecture (72) Invention Person Koichi Sakano 3 Daigoku Ishida housing complex 13-508 3 Daigoku Ishida Sakuragicho, Fushimi-ku, Kyoto-shi Kyoto Prefecture Keiji Goto

Claims (1)

[Claims] 1. A 3-nitro- represented by the following general formula (I):
A radiation sensitizer containing a 1,2,4-triazole compound as an active ingredient. (In the formula, X represents a halogen atom or —CO—R ₁ , R ₁ represents —O—R ₂ or —N (R ₃ ) R ₄ , R ₂ represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, An alkyl group having an ether bond or a hydroxyl group and an alkyl group having an ether bond are shown, R ₃ is a hydrogen atom, an alkyl group, a hydroxyalkyl group or an alkyl group having an ether bond, and R ₄ is represented by R _3. group or -R ₅ -N (R ₆₎
Shows the R _7, R ₅ represents an alkylene group, R ₆ and R ₇ represents a group represented by R _3, also alkylene or oxa by the R ₃ and R ₄ or R ₆ and R ₇ bound to each other It may represent a dialkylene group, and R ₃ and R ₆ may be bonded to each other to represent an alkylene group. R is a hydrogen atom, an alkyl group, a hydroxyalkyl group, -CH ₂ -CH (OH) indicates -CH ₂ -Y or -R ₈ -CO-R _1,
R ₈ represents an alkylene group, Y represents —O—R ₂ or —N (R ₃ ).
Indicates R ₄ . )