JP2862912B2 - 5 '-(4-propyl or 4-isopropylpiperazinyl) benzoxazinolifamycin derivative - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel rifamycin derivative or a salt thereof, and an antibacterial agent containing the same as an active ingredient. More specifically, the present invention provides a compound of formula (I): [Where A is the formula (R ¹ and R ² are the same or different and each represent a hydrogen atom or a methyl group, and R ³ represents a propyl group or an isopropyl group). The present invention relates to an antibacterial agent containing a rifamycin derivative or a pharmacologically acceptable salt thereof as an active ingredient.

[Problems to be Solved by the Prior Art / Invention] JP-A-63-183587 discloses a formula: {{Wherein, R ^a represents hydrogen or an acetyl group, R ^b represents hydrogen or a hydroxyl group, X ¹ is ｛R ^c is an alkyl group having 1 to 5 carbon atoms or an alkoxyalkyl group having 2 to 6 carbon atoms, R ^d is an alkyl group having 1 to 5 carbon atoms,-(CH ₂ ) _a X ² [a is 1 to And X ² represents an ethynyl group, a cyano group, (R ^e and R ^f are the same or different and hydrogen or carbon number 1 to 3
A group represented by OR ^g (R ^g is hydrogen or an alkyl group having 1 to 4 carbon atoms); (R ^h , R ⁱ , and R ^j are the same or different and hydrogen or carbon number 1
Which is an alkoxy group of 3 to 3), Wherein R ^k and R ^l are the same or different and are alkyl groups having 1 to 3 carbon atoms.], A cycloalkyl group having 3 to 8 carbon atoms, Wherein R ^m is hydrogen or an alkyl group having 1 to 3 carbon atoms, or a group represented by｝ which represents a group represented by -CH ₂ (CHOH) ₄ CH ₂ OH, Represents a 3- to 10-membered cyclic amino group having 2 to 9 carbon atoms, X ³ represents hydrogen or an alkyl group having 1 to 4 carbon atoms, X ⁴ represents hydrogen, an alkyl group having 1 to 3 carbon atoms, a hydroxyl group, (R ⁿ and ^Ro are the same or different and hydrogen or carbon number 1-4
Groups represented by alkyl as group) of, a hydroxyalkyl group having 1 to 3 carbon atoms, or cyclic or acyclic amino group having 2 to 6 carbon atoms, also come together and X ³ and X ⁴ =
O or a bond to -O (CH _{2) b} O- group represented by formula a group are 'in (an integer of b2~4),, (C and d are the same or different integers from 1 to 4), (E and f are the same or different integers from 1 to 4), ｛G and h represent the same or different integers of 1 to 4, R ^p and R ^q represent the same or different hydrogen or an alkyl group having 1 to 3 carbon atoms, X ⁵ represents an oxygen atom, a sulfur atom, NR ^r [R
^r is hydrogen or an alkyl group having 1 to 3 carbon atoms, A phenyl group represented by (R ^s is hydrogen or a trifluoromethyl group), (R ^t, R ^u is hydrogen or bonds to -OCH ₂ O-a is) rifamycin derivative and represented by a group represented by a group represented by a radical represented by}}} Salts are described. These compounds are important as antibacterial agents, especially as therapeutic agents for diseases caused by Gram-positive bacteria and acid-fast bacteria.

As a result of intensive studies, the present inventors have found that, among the rifamycin derivatives included in the above formula, certain compounds are particularly excellent in treating diseases caused by acid-fast bacilli. Completed.

[Means for Solving the Problems] The present invention provides a compound of formula (I): [Where A is the formula (R ¹ and R ² are the same or different and each represent a hydrogen atom or a methyl group, and R ³ represents a propyl group or an isopropyl group). The present invention relates to an antibacterial agent containing a rifamycin derivative or a pharmacologically acceptable salt thereof as an active ingredient.

The novel rifamycin derivatives represented by the above formula (I) according to the present invention include many organic solvents, halogenated hydrocarbons such as chloroform; alcohols such as ethyl alcohol; esters such as ethyl acetate; Hydrocarbons; soluble in ethers such as tetrahydrofuran.

The novel rifamycin derivative represented by the formula (I) according to the present invention can form a salt with either a base or an acid. As the base or acid that can be used to form a salt, any base or acid that can form a salt with the rifamycin derivative represented by the formula (I) can be selected. Specific examples of the salt with a base include (1) a metal salt, particularly a salt with an alkali metal or an alkaline earth metal, (2) an ammonium salt, (3) an amine salt, particularly methylamine,
There are salts with ethylamine, diethylamine, triethylamine, pyrrolidine, formolin, hexamethyleneimine and the like. Examples of salts with acids include (1) salts with mineral acids such as sulfuric acid and hydrochloric acid, (2) p-toluenesulfonic acid,
There are salts with organic acids such as trifluoroacetic acid and acetic acid.

The production of the novel rifamycin derivative represented by the above formula (I) according to the present invention can be carried out as follows.

That is, (A) Formula (II) synthesized by the method described in US Pat. No. 4,690,919: 3'-hydroxybenzoxazino rifamycin represented by methanol, ethanol, tetrahydrofuran,
Dissolved in an organic solvent such as N, N-dimethylformamide, dimethylsulfoxide, and the like. At a temperature from -20 ° C to the boiling point of the solvent, the amine represented by the formula AH (where A is the same as above) is acidified with an acid such as hydrochloric acid. It can be obtained by reacting for 1 hour to 1 month in the presence or absence of an oxidizing agent such as magenta dioxide in the presence or absence of oxidizing agents.

The rifamycin derivative represented by the formula (II) is 1
Good results are obtained when 0.5 to 10 mol, especially 1 to 3 mol, of the amine represented by the formula AH is used per mol.

As a reaction solvent, methanol, ethanol, isopropyl alcohol, tetrahydrofuran, pyridine, acetone, ethyl acetate, chloroform, N, N-dimethylformamide, dimethylsulfoxide and the like can be used, but pyridine, N, N-dimethylformamide, dimethyl Better results can be obtained by using sulfoxide or the like. The reaction temperature can be selected from -20 ° C to the boiling point of the solvent, but better results can be obtained by reacting at -5 ° C to 50 ° C. The reaction time is about one hour to one month, but the optimal reaction time depends on the reaction conditions such as the type and amount of amine used in the reaction, the presence or absence of oxidizing agent, the type and amount, and the reaction temperature. Should be tracked by thin layer chromatography or the like. Examples of the oxidizing agent that can be used in the reaction performed in the presence of the oxidizing agent include air, oxygen, manganese dioxide, lead dioxide, silver oxide, potassium ferricyanide, and hydrogen peroxide, and manganese dioxide, silver oxide, and potassium ferricyanide. You can get better results by choosing

(B) The rifamycin derivative represented by the formula (I) is replaced with the rifamycin derivative represented by the formula (II) used in the method described in (A), and the following formula (III): (Wherein X represents a halogen atom, an alkoxy group having 1 to 6 carbon atoms or a nitro group), and can be synthesized according to the method described in (A) using a rifamycin derivative represented by the formula (A). The synthesis conditions such as the reaction solvent and the reaction temperature may be the same as those described in the synthesis method (A).

A rifamycin derivative represented by the formula (III) as a starting material of the present synthesis method is represented by rifamycin S and a compound represented by the formula: (Wherein X is the same as described above) and can be obtained by reacting the compound with 3'-hydroxybenzoxazinolifamycin described in U.S. Pat. No. 4,690,919.

Although the rifamycin derivative represented by the formula (I) according to the present invention is a solid exhibiting a dark purple color, separation and purification from a reaction product are relatively easy. That is, an amine represented by the formula AH (where A is the same as described above) used for the excess reaction,
The reaction solvent and the like are removed, and the obtained crude product is purified by crystallization, column chromatography, etc., to obtain the desired rifamycin derivative.

The novel rifamycin derivative represented by the formula (I) can be reduced with a reducing agent such as ascorbic acid or sodium hydrosulfite to obtain a compound represented by the formula (IV): (Wherein, A is the same as described above). The rifamycin derivative represented by the formula (IV) is also novel and has a strong antibacterial action.

Table 1 shows representative examples of the novel rifamycin derivatives according to the present invention. In Table 1, the infrared absorption spectrum was measured by the potassium bromide tablet method. Thin layer chromatography was performed using Merck silica gel 60F _254, thin-layer chromatography plate (20cm × 20cm).
The nuclear magnetic resonance spectrum was measured using tetramethylsilane as an internal standard and a deuterated chloroform solution of the sample.

The rifamycin derivative according to the present invention exhibits strong antibacterial activity against Gram-positive bacteria and acid-fast bacteria.

The antimicrobial activity of the novel rifamycin derivative according to the present invention was determined by the standard method of the Japanese Society of Chemotherapy [Japanese Journal of Chemotherapy, Vol. 29,
76 (1981)]. Representative examples are shown in Table 2. As is apparent from Table 2, the novel rifamycin derivative according to the present invention has a strong antibacterial activity against Gram-positive bacteria and acid-fast bacteria. The derivative numbers in Table 2 correspond to the derivative numbers in Table 1.

The rifamycin derivative represented by the formula (I) according to the present invention has a strong antibacterial activity against Mycobacterium tuberculosis. Mycobacterium tuberculosis (Mycobacterium tuberculosis)
rculosis H ₃₇ the Rv strain) was cultured in Deyubosu (Dubos) medium, to prepare a bacterial solution of 1 mg / ml, the 10-fold dilution 0.05 ml 2m
l of 10% bovine serum was added to Kirchner liquid medium. For the determination, a multiple dilution series containing the test derivative was prepared according to a conventional method, and after culturing at 37 ° C. for 4 weeks, the concentration at which the growth of the bacteria was completely visually inhibited was defined as the minimum growth inhibitory concentration. The results are shown in Table 3. From the results shown here, it can be seen that the novel rifamycin derivative according to the present invention has strong antibacterial activity against Mycobacterium tuberculosis. The derivative numbers in Table 3 correspond to the derivative numbers in Table 1.

The rifamycin derivative of the formula (I) according to the present invention shows an excellent therapeutic effect on experimental infections by oral administration. As an example, the therapeutic effect of tuberculosis using mice will be described.

Male ddY mice, 5 weeks old, were used in groups of 10 per mouse. Mycobacterium tuberculosis cultivated on Dubos medium
H ₃₇ Rv strain) concentrated bacteria solution 0.2ml (several viable units 2.4 × 10 ⁸⁾ were inoculated infect mouse tail vein. From the day after infection, the nuclear test derivative was made into a 2.5% gum arabic suspension containing 0.2% Tween 80, and orally administered in 0.2 ml portions, ie, 200 μg / mouse. Controls received a 2.5% gum arabic solution containing 0.2% Tween 80 without test compound. The treatment was performed once a day, 6 days a week, and the therapeutic effect was evaluated by the survival of infected mice.

The result is shown in FIG. In the figure, a indicates the time of infection, and b indicates the start of processing. These results indicate that treatment with derivatives 1, 3, 4 or 5 according to the invention results in a treatment 40
No deaths were noted until day 1, derivatives 1, 3, 4 or 5
Shows extremely excellent therapeutic effect as compared with rifampicin as a control drug. In addition, derivatives A and B in which the alkyl group at the 4-position of the piperazinyl group of derivatives 4 and 5 are each substituted with a methyl group from a propyl group, that is, in formula (I), A is In the derivative A which is a group represented by It can be seen that the derivative B, which is a group represented by the formula, has almost no therapeutic effect.

Exactly the same test was carried out on derivative 2 using 15 ddY male mice per group. Observed up to 40 days of treatment,
No deaths were observed in the group to which derivative 2 was administered, whereas 5 out of 15 animals died in the rifampicin-administered group as a control. In the untreated control group, all mice died by 20 days from the start of the test.

In addition, a completely similar therapeutic test was carried out on a derivative C having the following structure described in US Pat. No. 4,690,919, using 20 ddY male mice per group. In the rifampicin-administered group as a control drug, 6 out of 20 animals survived, whereas in the group administered with derivative C, only 4 out of 20 animals survived. During this study, all mice died by day 19 in the untreated control group.

Also, derivative D having the following structure described in U.S. Pat. No. 4,690,919 and European Patent Application No.
The derivative E described in the specification of the specification having the following structure has been found in therapeutic tests to be less effective than rifampicin.

From the above results, it can be seen that the novel rifamycin derivative according to the present invention shows an extremely excellent therapeutic effect in a treatment test for Mycobacterium tuberculosis infection. In particular, by changing the size of the alkyl group of the N-alkylpiperazine introduced at the 5-position of 3'-hydroxybenzoxazinolifamycin, that is, by replacing the alkyl group with a propyl or isopropyl group from a methyl group. It is noteworthy that an excellent therapeutic effect that could not be obtained conventionally can be obtained. That is, while the known benzoxazinorifamycin derivative did not exceed the therapeutic effect of the existing drug rifampicin in the treatment test for Mycobacterium tuberculosis, the benzoxazinorifamycin derivative of the present invention showed Shows much better effect than

The novel rifamycin derivative shown in Table 1 according to the present invention was orally administered to mice at a rate of 1000 mg / kg, but showed no toxicity, indicating that the novel rifamycin derivative according to the present invention has low toxicity. Was.

As the preparation of the antibacterial agent containing the novel rifamycin derivative according to the present invention as an active ingredient, any preparation by oral, enteral or parenteral administration can be selected. Specific formulations include tablets, capsules, fine granules,
Syrups, suppositories, ointments and the like can be mentioned.
As carriers for the formulation of the antimicrobial agents according to the invention, use is made of organic or inorganic solid or liquid, usually inert pharmaceutical carrier materials which are suitable for oral, enteral or parenteral administration. Specifically, for example, crystalline cellulose, gelatin, lactose, starch, magnesium stearate, talc, vegetable and animal fats and oils, gums,
There are polyalkylene glycols. The ratio of the antimicrobial agent of the present invention to the carrier in the preparation can be varied between 0.2 and 100%. Also, the antimicrobial agent according to the present invention may include other antimicrobial agents compatible with this and other pharmaceuticals. In this case, it goes without saying that the antibacterial agent according to the present invention may not be the main component in the preparation.

The antimicrobial agent according to the present invention is generally administered at a dose that achieves the desired effect without side effects. The specific value should be determined by the judgment of a physician, but it will generally be about 10 mg to 10 g, preferably about 20 mg to 5 g per adult. The antibacterial agent of the present invention can be administered as a pharmaceutical preparation in a unit of 1 mg to 5 g, preferably 3 mg to 1 g, as an active ingredient.

[Examples] Hereinafter, examples will be described in order to further clarify the understanding of the present invention. However, these are merely examples, and do not limit the present invention. Note that the derivative numbers in the examples correspond to the derivative numbers in Table 1.

Example 1 (Synthesis of Derivative 1) Synthesis according to the method described in U.S. Pat. No. 4,690,919.
3'-Hydroxybenzoxazinolifamycin formed
2.0 g was dissolved in 20 ml of dimethyl sulfoxide, and 1-n-
Add 0.56 g of propylpiperazine, then manganese dioxide
2.0 g was added and the mixture was stirred and reacted at room temperature for 28 hours. Reaction liquid
After adding loloform and filtering off manganese dioxide, water and saturated diet
Wash sequentially with brine, dry over anhydrous sodium sulfate overnight and dissolve
The medium was distilled off under reduced pressure. Wako gel for residue Using C-200
Silica gel column chromatography [Developing solvent:
Roloform: methanol (98: 2)], then vinegar
Crystallized from ethyl acid-n-hexane, the desired derivative
0.35 g of 1 was obtained.

Example 2 (Synthesis of derivative 2) 1.6 g of 3'-hydroxybenzoxazinolifamycin was added to 20
Dissolve in 1 ml of dimethyl sulfoxide and add 1-isopropyl
Add 1.02 g of piperazine, then 0.8 g of manganese dioxide
In addition, the reaction was stirred at room temperature for 24 hours. Chloropho
After adding lum and filtering off manganese dioxide, water, saturated saline
And dried over anhydrous sodium sulfate.
The solvent was distilled off under reduced pressure. Wako gel for residue Using C-200
Twice by Ricagel column chromatography [Developing solvent:
Chloroform: methanol (97: 3)]
Crystallized from ethyl acid-n-hexane, the desired derivative
0.41 g of 2 was obtained.

Example 3 (Synthesis of Derivative 3) 4.8 g of 3'-hydroxybenzoxazinolifamycin
Was dissolved in 30 ml of dimethyl sulfoxide, and 1-isopro
3.43 g of pill-3-methylpiperazine were added, followed by the diacid
2.0 g of manganese oxide was added, and the mixture was stirred and reacted at room temperature for 86 hours.
Chloroform was added to the reaction solution, and manganese dioxide was filtered off.
Wash sequentially with water and saturated saline, and add anhydrous sodium sulfate.
After drying overnight, the solvent was distilled off under reduced pressure. Wako gel for residue C
Silica gel column chromatography using -200
[Developing solvent: chloroform: methanol (99: 1)]
And then crystallized twice from ethyl acetate-n-hexane.
2.36 g of the desired derivative 3 was obtained.

Example 4 (Synthesis of Derivative 4) 4.5 g of 3'-hydroxybenzoxazinolifamycin
Was dissolved in 45 ml of dimethyl sulfoxide to give 2,5-dimethyl
3.4 g of l-propylpiperazine were added, followed by methanol dioxide.
4.5 g of gangan was added and the mixture was stirred and reacted at room temperature for 66.5 hours. reaction
Chloroform was added to the solution, and manganese dioxide was filtered off.
Wash sequentially with saturated saline and dry over anhydrous sodium sulfate overnight
The solvent was evaporated under reduced pressure. Wako gel for residue C-200
4 times with silica gel column chromatography using
[Developing solvent: 1st time chloroform-methanol (49: 1),
2nd-4th chloroform-acetone (9: 1)] Vinegar after purification
Crystallization from ethyl acid-n-hexane system and the desired induction
0.50 g of body 4 was obtained.

Example 5 (Synthesis of Derivative 5) 4.4 g of 3'-hydroxybenzoxazinolifamycin
Was dissolved in 36 mg of dimethyl sulfoxide to give 2,6-dimethyl
1.31 g of l-propylpiperazine was added, followed by diacid
1.0 g of manganese oxide was added and the mixture was stirred and reacted at room temperature for 17 hours. Anti
Chloroform was added to the reaction solution, and manganese dioxide was filtered off.
Wash sequentially with water and saturated saline, then over anhydrous sodium sulfate overnight
It was dried and the solvent was distilled off under reduced pressure. Wako gel for residue C-
Silica gel column chromatography using 200
Times [Developing solvent: 1st time chloroform: methanol (98:
2) Second time chloroform: acetone: methanol (90:
10: 0.5)] After purification, chloroform and n-hexane
By crystallization, 2.15 g of the desired derivative 5 was obtained.

[Effect of the Invention] The rifamycin derivative of the present invention has a strong antibacterial effect and has an effect of having excellent physical properties.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the survival rate of mice and the number of treatment days when the rifamycin derivative of the present invention and other test compounds are orally administered to mice with tuberculosis.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Fumiyuki Kuze 461-1 Shimogamo Takagicho, Sakyo-ku, Kyoto-shi, Kyoto Japan (803) Inventor Kiyoshi Watanabe 5-15-41 Matsugaoka, Akashi-shi, Hyogo (56 References JP-A-63-183587 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C07D 498/18 A61K 31/535 CA (STN) REGISTRY (STN)

Claims (7)

(57) [Claims] (1) Formula (I): [Where A is the formula (R ¹ and R ² are the same or different and each represent a hydrogen atom or a methyl group, and R ³ represents a propyl group or an isopropyl group).] Or a salt thereof. 2. In the above formula (I), A represents the formula: The rifamycin derivative or a salt thereof according to claim 1, which is a group represented by the formula: 3. In the above formula (I), A is a formula: The rifamycin derivative or a salt thereof according to claim 1, which is a group represented by the formula: 4. In the above formula (I), A is a formula: The rifamycin derivative or a salt thereof according to claim 1, which is a group represented by the formula: 5. In the above formula (I), A is a formula: The rifamycin derivative or a salt thereof according to claim 1, which is a group represented by the formula: 6. In the above formula (I), A represents a formula: The rifamycin derivative or a salt thereof according to claim 1, which is a group represented by the formula: 7. Formula (I): [Where A is the formula (R ¹ and R ² are the same or different and each represent a hydrogen atom or a methyl group, and R ³ represents a propyl group or an isopropyl group). An antibacterial agent containing an acceptable salt as an active ingredient.