JPS6320210B2 - - Google Patents

Description

1 (wherein, R is a phenylene group; An anticancer agent containing phenylpolysilsesquioxane as an active ingredient, which consists of a structural unit represented by the following formula: alkali metal, alkaline earth metal, or ammonium.

[Detailed description of the invention]

The present invention relates to an anticancer agent containing a specific phenylpolysilsesquioxane as an active ingredient, and in particular provides an anticancer agent with extremely low toxicity. Conventionally, many natural and synthetic organic compounds have been known as anticancer agents. For example, mitomycin, an antibiotic, is currently used as an anticancer drug.
Pleomycin, etc., as well as synthetic products such as nitrogen mustard, 5-fluorouracil (5-
FU), ftorafur, etc. are used. However, since it was developed with selective toxicity, that is, it directly attacks and cures cancer cells, it naturally acts on normal cells as well, so it is highly toxic and has serious side effects. It was mostly hot. The present inventors have been conducting research on the synthesis and reactivity of organometallic compounds for many years. In recent years, as a variety of physiological activities have been discovered in organometallic compounds, we have focused on organosilicon compounds, which are generally known to have extremely low toxicity among organometallic compounds. We have been actively searching for organosilicon compounds that exhibit activity as anticancer substances, which are in desperate need of new development. As a result, certain organosilicon compounds, commonly referred to as phenylpolysilsesquioxanes, have been shown to cause cancer in Ehrlichi's ascites carcinoma, Walker carcinoma sarcoma 256.
We have completed the present invention by discovering that it exhibits a surprisingly high anti-cancer activity that can inhibit cancer cells such as ascites cancer, and even cure cancer cells in some cases. Therefore, an object of the present invention is to provide an anticancer agent with extremely low toxicity and significant anticancer activity. That is, the present invention (wherein, R is a phenylene group; This is an anticancer agent containing phenylpolysilsesquioxane as an active ingredient, which consists of structural units represented by the following formulas: alkali metal, alkaline earth metal, or ammonium. In the above formula, the "halogen atom" represented by the group is a methyl group, ethyl group, propyl group, etc., especially a lower alkyl group; "haloalkyl group"
Especially the trifluoromethyl group;--COOM
For example, COONa, COOK, COOLi,
COOCa _1/2 , COOMg _1/2 , COONH ₄ , COONR' ₄ (where R' represents a lower alkyl group such as methyl, ethyl, propyl, butyl), and the like. Furthermore, the "phenylene group" represented by the functional group R is any of ortho-, meta-, and para-phenylene groups. Phenylpolysilsesquioxane, which is composed of the structural unit () (hereinafter sometimes simply abbreviated as O _1.5 SiRX) used in the present invention, is a well-known substance, and the water repellency of silicon compounds,
It is also used industrially as a raw material for textile treatment agents due to its oil repellency. However, the history of research on the physiological and pharmacological activities of organosilicon compounds is relatively new, even when looking at organosilicon compounds in general, and it was not until 1971 that the Soviet Union published books and reviews on the physiological effects of organosilicon compounds. The situation was first described by the chemists Voronkov et al.
“Advances in Chemistry of Biologically
Active Organosilicon Compounds，”24th
International Congress of Pure and Applied
Chemistry, Vol. 4 , 45 (1973)]. The review includes the acute toxicity of organotrihalogenosilane compounds and organotriethoxysilane compounds, the physiological activity (e.g. antibacterial properties, etc.) of functional organotrialkylsilanes such as (CH ₃ CH ₂ ) ₃ SiCH ₂ CH ₂ CH ₂ NH ₂ ), but most of them are related to monomers, and no research has been found on the physiological activity of silicone polymers such as phenylpolysilsesquioxane. Furthermore, if we focus on organosilicon compounds that have anticancer activity, RaSi, which was discovered by Voronkov,
The only known silatrane compound is represented by the structural formula (OCH ₂ CH ₂ ) ₃ N (wherein Ra represents various functional organic groups). The book “Biochemistry of Silicon and Related” by I.Lindqvist
Problems,” p. 395 (1977)].Silatrane compounds belong to the monomer class of organosilicon compounds, and there has also been a report by Stoner et al. that organosilicon compounds are carcinogenic to mice. [GDStoner, EK Weisburger, M.
B. Shimkin, J. Nat. Can. Inst., 54 495 (1975)]. This time, surprisingly, as mentioned above, phenylpolysilsesquioxane, which consists of the structural unit represented by the formula O _1.5 SiRX, has low toxicity to warm-blooded animals in general, but The fact that it exhibits extremely high anticancer activity against cancer cells was discovered for the first time by the present inventors. Structural unit formula that is the active ingredient of the anticancer agent of the present invention
O _1.5 Phenylpolysilsesquioxane consisting of the structural unit represented by SiRX is generally produced by hydrolysis-condensation of the corresponding silane compound by a method known per se. (For example, see Japanese Patent Publication No. 36-7547.)
Phenylpolysilsesquioxane has the general formula (O _1.5
SiRX) n, and its structure is mainly a three-dimensional cage-like cyclic substance (4-12 mer, i.e. n = 4-12)
[For example, see Kumada and Okawara, "Organosilicon Chemistry," pp. 271-280].
It is not clear why such phenylpolysilsesquioxane exhibits high anticancer activity, but it is mainly due to the formula

It is presumed that this is caused by a siloxane bond having an organosilicon group represented by the formula. That is, this is used in the present invention,

【Formula】Ya

While polysilsesquioxanes such as [Formula] show high anticancer activity,

【Formula】Ya

This can be fully inferred from the fact that compounds such as [Formula] show only low anticancer activity. Furthermore, the properties of the above-mentioned phenylpolysilsesquioxane vary depending on the type of group X, etc., and cannot be generalized. Phenyltrihalogenosilane compounds or phenyltrialkoxysilane compounds, which are common raw materials for these, are generally liquid or low-melting solid, whereas phenylpolysilsesquioxane obtained by hydrolysis is usually It is a solid, and in some cases, a viscous solid. That is, the phenylpolysilsesquioxane having the above functional group is insoluble or poorly soluble in water, but exhibits various solubility in organic solvents depending on the type of functional group. For example, the group
Phenylpolysilsesquioxanes having an alkyl group, an alkoxy group, a phenoxy group, a chloro group, or a bromo group include benzene, toluene, ether, tetrahydrofuran, dioxane, alcohol, chloroform, acetone, acetonitrile, N,N-dimethyl It is soluble or easily soluble in common organic solvents such as formamide, but insoluble in water. Carboxyl group and - as group X
Phenylpolysilsesquioxanes having a COOM group (except when M is an alkyl group) are soluble in strong alkaline aqueous solutions, but sparingly soluble in acidic aqueous solutions and slightly soluble in pure water. and N,N-
Although it may be soluble in polar nonaqueous solvents such as dimethylformamide, it is usually insoluble or sparingly soluble in nonpolar solvents such as ether, benzene, and toluene. Phenylpolysilsesquioxanes having a cyano group as the group X are usually insoluble in water and sparingly soluble in common organic solvents. The phenylpolysilsesquioxane used as an active ingredient in the present invention is extremely effective against Ehrlichi's ascites carcinoma and Walker carcinoma sarcoma 256 ascites carcinoma in mice and rats, as demonstrated in the Examples below. It exhibits strong anticancer activity and low toxicity to warm-blooded animals, and can be used as an anticancer agent for the prevention, treatment, or treatment of various cancers. Therefore, the anticancer agent of the present invention can be administered to patients orally, parenterally (for example, intramuscularly, intravenously, subcutaneously, intraperitoneally, rectally), or locally, and the active ingredients The effective dosage of phenylpolysilsesquioxane varies depending on the age, weight, severity of symptoms, type of cancer, etc. of the patient to whom it is administered, but in general, it is 800 to 1 mg/Kg/day, Preferably it can be 500-10 mg/Kg/day.
The daily dose may be administered only once a day or several times a day (3
It can be administered in divided doses (~5 times). Also,
It goes without saying that the above dosages are merely guidelines and it is possible to administer doses beyond the above range at the discretion of the treating physician. When administering the active ingredient, the phenylpolysilsesquioxane can be formulated into various dosage forms depending on the desired administration method (oral, parenteral, or topical). For example, for oral administration, it can be formulated into tablets, pills, sugar-coated tablets, powder sachets, granules, syrups, capsules, etc., and for parenteral administration, it can be formulated into solutions, suspensions, suppositories, etc. It can be formulated into dosage forms, and for topical administration, it can be formulated into dosage forms such as ointments, plasters, and creams. The concentration of the active ingredient in these preparations is not particularly limited and can vary widely depending on the dosage form, but is generally 0.05 to 90% by weight,
Preferably, the concentration can be about 1 to 60% by weight. As excipients that can be used in the above formulation, any excipient commonly used in the field can be used, and for solid form formulations, for example, lactose,
Examples include starch, glycine, crystalline cellulose, mannite, magnesium stearate, liquid paraffin, calcium carbonate, sodium bicarbonate, etc. For liquid form preparations, for example, physiological saline, surfactant solution, glucose solution, etc. , alcohol, esters, sodium hydroxide solution and the like. Specific examples of such formulations are as follows. Formulation Example 1: Injection 0.1 part by weight of phenylpolysilsesquioxane consisting of the structural unit of the above formula (), 1 part by weight of peanut oil
Parts by weight and aluminum stearate gel 100
Aseptically dispensed into vials containing parts by weight and sealed to remove moisture and bacteria.
Before use, a suspension injection was prepared by adding physiological saline containing 0.5% lidocaine. Formulation example 2: Capsule 0.6 parts by weight of magnesium stearate and 4.5 parts by weight of lactose
Parts by weight were added and stirred and mixed to make the mixture uniform.Furthermore, 5 parts by weight of lactose and 10 parts by weight of crystalline cellulose were added and mixed. To this mixture, 20 parts by weight of phenylpolysilsesquioxane consisting of the structural unit of the formula (2), which had been pulverized in advance, was added and mixed again to obtain a prepared powder. This powder was used to produce gelatin capsules using a capsule filling machine. Formulation Example 3: Ointment After dissolving 10 parts by weight of stearyl alcohol, 20 parts by weight of liquid paraffin, and 160 parts by weight of petrolatum at 80°C, a solution consisting of 0.5 g of cholesterol and the structural unit of the above formula () that has been pulverized in advance is prepared. 10 parts by weight of phenylpolysilsesquioxane were added with thorough stirring, and after further stirring, the mixture was allowed to stand at room temperature to obtain an appropriate hardness to obtain a softener. Formulation Example 4: Tablet After thoroughly mixing and pulverizing 25 parts by weight of phenylpolysilsesquioxane consisting of the structural unit of the above formula () and 20 parts by weight of mannitrate, 4.7 parts by weight of potato starch as a starch paste was added to form granules. It became. The particles were passed through a 60-mesh sieve, dried to a predetermined weight, and passed through a 16-mesh sieve. Next, the particles were mixed with 0.3 parts by weight of magnesium stearate, smoothed, and compressed into uncoated tablets of a predetermined size using a tablet machine in a conventional manner. As described above, the phenylpolysilsesquioxane consisting of the structural unit of the formula () used as an active ingredient in the present invention is generally obtained by hydrolyzing the corresponding phenylsilane compound.
The degree of polymerization and condensation form of the resulting phenylpolysilsesquioxane often differs depending on the conditions under which the corresponding phenylsilane compound is hydrolyzed; generally, the more mild the conditions are for hydrolysis, the lower the molecular weight. (low degree of polymerization) tends to be easily obtained. Furthermore, the molecular weight (degree of polymerization) can be changed by once again changing the conditions and subjecting the synthesized phenylpolysilsesquioxane to acid, base, or heat treatment. The above hydrolysis can be carried out by dropping the phenylsilane compound directly or by dissolving it in an organic solvent and dropping it into cold water while stirring. If an organic solvent is used and the resulting phenylpolysilsesquioxane is soluble in the solvent, the solvent may be distilled off. By removing the mixture, the desired phenylpolysilsesquioxane compound can be isolated. In addition, in the present invention, mainly by hydrolyzing a phenyltrihalogenosilane compound or a phenyltrialkoxysilane compound purified to a pure state under mild conditions,
A pure phenylpolysilsesquioxane compound was obtained and served as a sample for acute toxicity test as well as anticancer test. However, carboxyphenyl polysils obtained by oxidizing the corresponding tolyl polysilsesquioxane, such as 3-carboxyphenyl polysilsesquioxane, 2-carboxyphenyl polysilsesquioxane, etc. It has been confirmed that sesquioxane exhibits almost the same anticancer activity as a pure sesquioxane even in samples containing compounds lacking some carboxyphenyl groups. It should be noted that the phenylpolysilsesquioxane compound used in the present invention generally has a relatively low degree of polymerization (mainly composed of 4-12 mers, and preferably 6-8 mers). This was confirmed using a phenylpolysilsesquioxane compound that is soluble in a solvent, but it was also confirmed that the phenylpolysilsesquioxane compound, which is synthesized under stronger hydrolysis conditions and whose degree of polymerization is thought to be greater, also showed resistance. Confirmed to have cancer activity. The method for synthesizing the phenylpolysilsesquioxane comprising the structural unit represented by the formula () used in the present invention will be described in more detail below. The above formula

Among the phenylpolysilsesquioxanes consisting of the structural unit of [Formula],
Group X is a hydrogen atom, a halogen atom, an alkoxy group,
Phenoxy groups and alkyl groups can be easily synthesized by hydrolyzing the corresponding phenylsilane compounds. In addition, in the case of cyanophenyl polysilsesquioxane (X = CN), the present inventors have found that it can be obtained pure by hydrolyzing the corresponding cyanophenyltriethoxysilane in an extremely weakly acidic aqueous solution. I found it. That is,
Cyanophenyltriethoxysilane is stable in pure water and does not change even if left under stirring overnight, but when a few drops of concentrated hydrochloric acid is added to this system and stirring is continued, oily cyanophenyltriethoxysilane is formed. The silane undergoes gradual hydrolysis and pure cyanophenyl polysilsesquioxane is obtained as a white solid. Carboxyphenylpolysilsesquioxanes (X=COOH) are produced by first hydrolyzing cyanophenyltriethoxysilane with a 5% aqueous sodium hydroxide solution, acidifying the homogeneous transparent solution with hydrochloric acid, and precipitating it. The present inventors discovered for the first time that it is possible to isolate extremely pure substances by passing through the white precipitate. A separate method for synthesizing carboxyl phenyl polysilsesquioxanes has already been reported in U.S. Patent No.
No. 3,481,815 discloses the oxidation of the corresponding methylphenylsilsesquioxane or tolylsilsesquioxane with alkaline potassium permanganate. The present inventor also synthesized carboxyphenyl polysilsesquioxane by the method described in the above US patent, and found that in the case of para-tolyl polysilsesquioxane, purification was repeated after synthesis. Almost pure 4
-Carboxyphenylpolysilsesquioxane could be obtained, but when methatolylpolysilsesquioxane and orthotolylpolysilsesquioxane were used, the phenyl group moiety was eliminated and the desired result was not achieved. It was not possible to obtain the carboxyphenyl polysilsesquioxane in high yield. Carbamoylphenyl polysilsesquioxane can be produced by partially hydrolyzing the corresponding cyanopolysilsesquioxane, or by first converting the corresponding carboxyphenyl polysilsesquioxane into an acid halide using thionyl chloride or the like. ,
It can be synthesized by reacting with ammonia. Further, alkoxycarbonylphenyl polysilsesquioxane can also be easily synthesized by reacting the acid halide with alcohol. The hydrogen atom of the carboxy group in carboxyphenyl polysilsesquioxane is an alkali metal,
Salts of carboxyphenyl polysilsesquioxane substituted with alkaline earth metals, ammonium, etc. can be prepared by dissolving the corresponding carboxyphenyl polysilsesquioxane in a solvent such as water, alcohol, or acetonitrile; After suspension, it can be obtained by adding an equivalent amount of the corresponding aqueous alkali solution or solid alkali, and further, in the case of ammonium salts, by passing ammonia gas through the silsesquioxane solution. As the alkaline solution or solid alkali, in addition to hydroxides, oxides and carbonates can also be used as appropriate. The structure of the resulting phenylpolysilsesquioxane consisting of structural units represented by the above formula () is:
Confirm the characteristic absorption of the functional groups contained in the infrared absorption spectrum, the absorption of phenyl groups, and the strong absorption of siloxane groups, as well as hydrogen, carbon, and silicon (chlorine, bromine, fluorine, and nitrogen, if necessary). It can be reliably determined by conducting elemental analysis. The present inventors have confirmed that hydrolysis of a pure phenylsilane compound under mild conditions yields the corresponding pure phenylpolysilsesquioxane or its hydrate in almost all cases. There is. Next, a production example of phenylpolysilsesquioxane used as an active ingredient in the anticancer agent of the present invention, a pharmacological activity test method, and the results thereof will be shown. Production example 1: 4-methoxyphenylpolysilsesquioxane 4-methoxyphenyltriethoxysilane 7.80
3 g of concentrated hydrochloric acid to a mixture of 150 ml of cold water (2-4℃)
After adding the drops and stirring overnight, the volatiles were removed by distillation, and the residue was dissolved in 50 ml of acetone and diluted with 300 ml of water.
Drip into ml. Take the generated precipitate, dry it, and
-4.82 g of methoxyphenyl polysilsesquioxane monohydrate was obtained. In a similar manner, phenylpolysilsesquioxane derivatives such as alkyl, alkoxy, and phenoxy were also synthesized using the corresponding phenyltriethoxysilanes. Table 1 shows the elemental analysis values and infrared absorption spectrum values of the obtained phenylpolysilsesquioxane. Production example 2: 4-cyanophenylpolysilsesquioxane 4-cyanophenyltriethoxysilane 11.26
10 drops of concentrated hydrochloric acid were added to a mixture of g and 200 ml of water, and stirring was continued overnight. The white solid produced was washed with water,
Hemihydrate of 4-cyanophenylpolysilsesquioxane was obtained by vacuum drying at 100℃ for 5 hours.
5.66g was obtained. The elemental analysis values and infrared absorption spectrum values are shown in Table 1. Production example 3: 4-carboxypolyphenylsilsesquioxane 4-cyanophenyltriethoxysilane 15.93
10 drops of concentrated hydrochloric acid were added to a mixture of g and 200 ml of water, and the mixture was left stirring overnight. Take the formed white precipitate and crush it, 5
% sodium hydroxide aqueous solution for 6 hours.
Warmed to 55-65°C. After cooling, the pH was adjusted to 1 with hydrochloric acid, and the resulting white precipitate was filtered and dried to obtain 4-carboxyphenylsilsesquioxane 1.
6.65 g of hydrate was obtained. Other carboxypolyphenylsilsesquioxane derivatives were similarly synthesized using the corresponding cyanophenyltriethoxysilanes according to the above method. Table 1 shows the elemental analysis and infrared absorption spectrum values of the carboxypolyphenylsilsesquioxane obtained above. Production Example 4: Other phenylpolysilsesquioxanes Tables 3 to 4 below were prepared using the corresponding phenyltriethoxysilane according to the method described above.
The phenylpolysilsesquioxane shown in was synthesized and confirmed by elemental analysis and infrared absorption spectroscopy. Those values are shown in Table 1.

【table】

[Table] Test Example 1: Toxicity Test 4-Carboxyphenylpolysilsesquioxane was added to physiological saline containing surfactant Tween 80 to prepare sample solution 8, which is a suspension containing a specified amount of sample.
Created a type. Using this sample solution, a test was conducted for 14 days by intraperitoneally injecting each of 10 male CDF ₁ mice weighing around 20 g on consecutive days.
The LD ₅₀ of the acute toxicity was determined by the Richfield and Wilcoxon method and was found to be 750 mg/Kg. The details are shown in Table 2.

[Table] Test Example 2: Toxicity Test Six types of samples, which are suspensions containing 4-cyanophenylpolysilsesquioxane in physiological saline containing Tween 80 and a specified amount of sample depending on the dose. A liquid was prepared. Using this sample solution, 5012mg/
Kg, 3160mg/Kg, 1000mg/Kg, 316mg/Kg, 100
except that the doses were mg/Kg and 31.6 mg/Kg.
As a result of determining LD ₅₀ in the same manner as in Example 1,
It was more than 5012mg/Kg. Test Example 3: Anticancer activity test against Ehrlichi's ascites carcinoma in mice The phenylpolysilsesquioxanes shown in Table 3 below were prepared in a 2% NaHCO ₃ solution (containing the corresponding Na salt) and b physiological saline ( A suspension of Tween 80 (0.85%) and Tween 80 was used to prepare a sample solution according to the dose. Using this sample solution, the number of Ehrlichi cancer cells was 5.
×10 ⁶ mice were intraperitoneally injected into 6 Swiss mice (male) for 9 days, and the survival effect was 50
The details of the results of the investigation over a period of days and the calculation of T/C% are shown in Table 3 together with the control. In other words, the mean survival time (MST) is determined from the above 50-day survival effect results, and is usually 20 to 70 days.
T/C (%) was calculated by comparing the mean survival days of controls using mice. That is, the average survival days were determined for the test subject (T) and the control subject (C),
Calculated as T/C x 100 (%). For the approximate value, if 6 test animals are used, the number of days the 4th animal dies (or the number of days the 6th animal dies if 10 animals are used) is taken as the average survival time, and this is the number of days the test animals survive in the same manner. It is calculated by dividing the value calculated by the average survival days and multiplying it by 100. In addition, in the test example, accurate values calculated using a computer are described. In addition, in the test example, T/C was calculated by administering three different drug doses for simplicity.
(%) showed the largest value.

【table】

[Table] Test Example 4: Anticancer test against Ehrlichi's ascites carcinoma in mice Swiss mice ( The drug was intraperitoneally injected into 6 male mice every day for 9 days to test the effect on Ehrlichi's ascites carcinoma in mice. Obtained T/C%
The values are shown in Table 4.

【table】

【table】

[Table] Test Example 5: Anticancer test against Walker carcinosarcoma 256 ascites cancer in rats. Rat Walker Carcinosarcoma Using Rusequioxane
The effect on 256 ascites cancers was tested. That is, the sample was suspended in a physiological saline (0.85%) solution containing the surfactant Tween 80 to prepare three types of sample solutions according to the dosage, and the number of Walker Carcinosarcoma 256 cancer cells 1 was intraperitoneally administered. Intraperitoneal injections were administered to 6 Sprague-Dawley rats (female) with ×10 ⁵ cells for 5 consecutive days, and the survival effect was investigated over a period of 2 months. The results obtained are shown in Table 5.

【table】

Claims (1)

[Claims]