JP2863821B2 - Antiprotozoal agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antiprotozoal agent, particularly an antiprotozoal agent effective against Trypanosoma Cruzi .

[0002]

2. Description of the Related Art In recent years, diseases caused by protozoa have become a serious problem in developing countries such as South America due to high mortality. These diseases are not only a problem for indigenous peoples, but also a serious problem for engineers in developed countries who are involved in these regional development assistance, and it can be said that these diseases are hindering the development of these regions. It's not too much to say.

[0003] Among these protozoan diseases, in particular, those caused by Trypanosoma Cruzi , in which no effective antiprotozoal agent is present, it is not rare that myocardium and the like are damaged and killed during acute infection. In addition, tens of millions of people have chronic infections, which is also a top priority in the WHO.

[0004]

Under these circumstances, the present inventor has determined that the 2-nitroimidazole derivative represented by the following general formula (1) is effective as an antiprotozoal agent, particularly against trypanosoma cruzi. Headline, patent application was filed earlier (Japanese Patent Application No. 2-2756). However, although this antiprotozoal agent is effective for acute infection, it has a problem that the parasite cannot be completely eliminated from the body of a protozoan infected person.

[0005] Accordingly, an object of the present invention is to provide an antiprotozoal agent which enables complete elimination of an insect body from the body of a protozoan infected person.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above-mentioned circumstances, and as a result, when a 2-nitroimidazole derivative represented by the following general formula (1) and an anionic polymer are used in combination, an antigen is obtained. Insect action, especially trypanosoma
The present inventors have found that the antiprotozoal action on cruzi is improved, and that an antiprotozoal agent capable of completely eliminating the worms from the body of a protozoan infected person is obtained, thus completing the present invention.

That is, the present invention provides the following general formula (1)

[0008]

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[0009] It is intended to provide an antiprotozoal agent containing a 2-nitroimidazole derivative represented by the following formula and an anionic polymer.

[0010] One of the components of the antiprotozoal agent of the present invention, 2
The -nitroimidazole derivative (1) is a known compound, and can be produced, for example, according to the following reaction formula.

[0011]

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That is, 2-nitroimidazole (2)
Is reacted with a halide (3), and then deacetylated from the obtained product (4) to produce a 2-nitroimidazole derivative (1). The reaction between 2-nitroimidazole (2) and halide (3) is preferably performed in a solvent such as dimethylformamide in the presence of a base such as triethylamine. Deacetylation of the obtained product (4) is preferably carried out with a base such as triethylamine or pyridine in a mixed solvent of acetonitrile and water. After completion of the reaction, the 2-nitroimidazole derivative (1) can be purified by concentrating the reaction mixture, separating the mixture by column chromatography or the like, and then reconcentrating and recrystallizing.

The 2-nitroimidazole derivative (1) thus obtained has an excellent antiprotozoal activity even when administered alone and is highly safe, as shown in Reference Examples below. Useful as an active ingredient.

As the anionic polymer to be incorporated in the antiprotozoal agent of the present invention, any of a natural system and a synthetic system can be used. Examples of natural anionic polymers include mucopolysaccharides such as hyaluronic acid, chondroitin sulfate or salts thereof; alginic acid, carboxymethyl cellulose,
Hemicelluloses such as hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylethylcellulose, methylcellulose, carboxymethylamylose and salts thereof are included. Examples of the synthetic anionic polymer include a polymer in which the following monomers (a) to (c) are independently polymerized, and a polymer in which the following monomers (a) to (c) are copolymerized with another polymerizable monomer.

(A) unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid and maleic acid; (B) unsaturated sulfonic acid monomers such as styrene sulfonic acid; (C) unsaturated phosphoric acid monomers such as vinylphosphonic acid and acid phosphoxyethyl (meth) acrylate;

Specific examples of the synthetic anionic polymer include an acrylic acid-diisobutyl vinyl ether copolymer. Further, these anionic polymers are preferably water-soluble.

These anionic polymers themselves do not exhibit antiprotozoal activity, but when used in combination with the above-mentioned 2-nitroimidazole derivative (1), the antiprotozoal activity of the 2-nitroimidazole derivative (1) is remarkably improved. be able to. In particular, it is excellent in that the parasites can be completely eliminated from the body of a protozoan-infected patient and chronic symptoms can be prevented.

The blending amount of the anionic polymer in the antiprotozoal agent of the present invention is not particularly limited, but is preferably 1/1000 to 1/1 by weight relative to the 2-nitroimidazole derivative (1).

The antiprotozoal agent of the present invention comprises the above-mentioned 2-nitroimidazole derivative (1) and an anionic polymer in the usual manner in the form of tablets, granules, powders, capsules, suspensions, injections, suppositories. It can be manufactured by preparing various dosage forms such as

In order to prepare a solid preparation, various additives such as an excipient, a binder, a disintegrant, a lubricant, a coloring agent and the like are added to the 2-nitroimidazole derivative (1) and the anionic polymer. It is preferable to add tablets, granules, powders, capsules, suppositories and the like by a conventional method after adding agents, flavoring agents, flavoring agents, bulking agents, coating agents and the like. Here, excipients include sugars, starch, inorganic substances, plant powder, and the like; binders include starch paste, gum arabic,
Gelatin, polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), etc .; disintegrants include starch, agar, gelatin powder, calcium carbonate, sodium hydrogencarbonate, etc .; lubricants, magnesium stearate, talc , Hydrogenated vegetable oils, macrogol, silicone oils and the like; coatings include sugar coatings (sucrose, shellac), glues (gelatin, glycerin, sorbitol), film coatings, enteric coatings and the like.

When preparing an injection, the 2-nitroimidazole derivative (1) and the anionic polymer are previously dissolved, dispersed, emulsified or the like in an aqueous carrier such as distilled water for injection, or powdered for injection. Then, it is sufficient to dissolve it for business. The method of administering the injection includes intravenous administration, intraarterial administration, intraportal administration, intraperitoneal administration, intramuscular administration, and subcutaneous administration.

The dosage of the antiprotozoal agent of the present invention varies depending on the age, weight, sex, administration method, physical condition and disease state of the patient.
As a nitroimidazole derivative (1), 10 to 3000 mg per day for oral administration per adult and 10 to 10 mg per day for parenteral administration
1500mg is appropriate.

[0023]

Next, the present invention will be described in more detail with reference to Reference Examples and Examples, but the present invention is not limited thereto.

Reference Example 1 Antiprotozoal effect 1 (in vitro): A204 cells (derived from rhabdomyomas) cultured in advance at 37 ° C. after infecting Trypanosoma cruzi and cultured in a 24-well tissue culture plate Then, it was confirmed that about 10 ⁵ free insects appeared. This was treated with a 50 μmol, 100 μmol, or 500 μmol solution of the compounds (A) to (C), cultured at 37 ° C. for 24 hours, and observed under a microscope to score the survival or death of the parasite. The criteria for scoring are as described below. Table 1 shows the results. The medium used was Dulbecco's Modified Eamery Dium from Dainippon Pharmaceuticals supplemented with 10% calf serum. Controls were performed in the same manner except that compounds (A) to (C) were not added.

[0025]

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Judgment criteria +++: Same as control ++: Slightly less than control +: Less than control ±: Slightly surviving parasites-: No surviving parasites

[0027]

[Table 1]

From the above results, it was found that the compounds (A) to (C) exhibited excellent antiprotozoal effects.

Reference Example 2 Antiprotozoal Effect 2 (In Vitro): Trypanosoma cruzi was added to Nippon Pharmaceutical GIT medium (serum-free medium) at a concentration of 12.4 mol of hemin, and cultured at 27 ° C. Compound (A) was added to 50 μl
120 hours after adding mol, 100 μmol, 250 μmol, and 500 μmol, the mixture was observed under a microscope, and the life and death of the worm was scored using the criterion of Reference Example 1. Table 2 shows the results. In addition, what did not add the compound (A) was used as a control.

[0030]

[Table 2]

From the above results, it was found that the compound (A) exhibited an excellent antiprotozoal effect.

Reference Example 3 Antiprotozoal effect 3 (in vivo):
Four-week-old male ICR mice were intraperitoneally administered with 400,000 Trypanosoma cruzi (Tulahven strain). On day 5, 6, 7, 8, and 9 after administration, compound (A)
Was added to the control group, and physiological saline was similarly administered in place of the compound (A). The antiprotozoal effect of the compound (A) was measured from the number of days the mice survived.

As a result, 2 out of 3 animals in the control group
The animals survived 14 days and the animals survived 15 days, whereas all three animals in the compound (A) administration group survived 50 days or more. From this result, it was found that the compound (A) has an excellent antiprotozoal effect even in vivo.

Reference Example 4 Antiprotozoal effect 4 (in vivo):
Five-week-old male C3H / Hecrj mice were intraperitoneally administered with 200,000 trypanosoma cruzi (Tulahven strain).
Compound (A) on days 4, 5, 6, 7 and 8 after administration
Was added to the control group, and physiological saline was similarly administered in place of the compound (A). The antiprotozoal effect of the compound (A) was measured from the number of days the mice survived.

As a result, while the control group had 12 surviving days, the compound (A) administration group had 12 days.
All animals were older than 20 days. From this, compound (A)
Shows that it has an excellent antiprotozoal effect.

Example 1 Antiprotozoal effect 5 (in vivo):
Four-week-old male ICR mice were grouped into five groups of three each.
Groups 2 and 5 received 4.4 mg of acrylic acid-diisobutyl vinyl ether copolymer (monomer ratio 1: 1, average molecular weight 1.29 × 10 ⁵ ) dissolved in 0.2 ml of saline. 2
Day Trypanosoma Cluj (Tulahven str
ain) 400,000 were administered intraperitoneally. First day 5, 6, 7, 8, and 9 days after administration of Trypanosoma cruzi
Groups and the second group were administered with physiological saline, and the third and fifth groups were administered with the compound (A) dissolved at 200 mg / kg in saline. On the 5th day after administration of Trypanosoma cruzi, 4.4 mg of the acrylic acid-diisobutylvinyl ether copolymer (monomer ratio 1: 1, average molecular weight 1.29 × 10 ⁵ ) and compound (A) 200 mg / kg were intraperitoneally administered to the fourth group. On days 6, 7, 8, and 9, compound (A) was intraperitoneally administered at 200 mg / kg. Thereafter, observation was made up to 60 days after administration of Trypanosoma cruzi. In addition, those surviving on the 60th day were killed and dissected, and the organs were observed under a microscope for the presence of insects. Table 3 shows the results.

Criteria for the presence or absence of insects +: Insects are clearly recognized ±: Insects are observed but very slight-: No insects are observed

[0038]

[Table 3]

According to Table 3, the compound (A) administration group (3,
Nos. 4 and 5) did not have any deaths and showed antiprotozoal effects. In addition, in the combination group of the compound (A) and the anionic polymer (groups 4 and 5), almost no worms disappeared from the body.

Example 2 Acute toxicity: An acute toxicity test was performed by intraperitoneal administration using ICR mice. The observation was performed for 14 days after the administration. Table 4 shows the results.

[0041]

[Table 4]

[0042]

Since the antiprotozoal agent of the present invention exhibits excellent antiprotozoal activity, it is extremely useful as a prophylactic and therapeutic agent for acute and chronic infections by various protozoa, and especially from the body of infected patients. Its ability to eliminate the body makes it very effective in treating tens of millions of infected people because it is effective against Trypanosoma cruzi.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadashi Kobayashi 3-9-15 Tajiri, Ichikawa-shi, Chiba Fuji Mansion 605 (58) Field surveyed (Int.Cl. ⁶ , DB name) A61K 31/415 AEB A61K 31/74 A61K 47/32 A61K 47/36 A61K 47/38 CA (STN)

Claims (1)

(57) [Claims] 1. The following general formula (1): An antiprotozoal agent comprising a 2-nitroimidazole derivative represented by the formula: and an anionic polymer.