RU2802959C1 - Aniline-substituted nitrobenzofuroxan derivatives having anti-antibalantidiosis activity - Google Patents

Abstract

FIELD: organic chemistry.

SUBSTANCE: aniline derivatives of nitrobenzofuroxan (1-31) of general formula I, where R¹, R² R³ are given in the claims. The aniline-substituted derivatives of nitrobenzofuroxan according to the invention have antibalantidiosis activity.

EFFECT: aniline-substituted nitrobenzofuroxan derivatives having anti-antibalantidiosis activity at low concentrations (0.001 wt.%).

3 cl, 3 dwg, 2 tbl, 31 ex

Description

The invention relates to the field of organic chemistry, in particular, to new nitrogen- and oxygen-containing heterocyclic compounds, namely to stable aniline-substituted derivatives of 5-nitro-4,6-dichloro- and 4,6-dinitro-5,7-dichloro-benzofuroxans general formula I ( 1-31 ), which have high antibalantidiosis activity at low concentrations (0.001 wt.%) and which can find application in the field of veterinary medicine and medicine.

,

Where:

The development of new domestic drugs is currently, in connection with EU sanctions, put by the Russian state among the main priority areas of socio-economic development and national security of our country. Therefore, in terms of adaptation to new market conditions, the fundamental task of organic, pharmaceutical and medicinal chemistry is the development of new domestic effective drugs with high physiological activity and minimal toxicity. To successfully implement the task set by the government, it is necessary to solve issues that are at the intersection of many fields of science - chemistry, physics, biology, veterinary medicine and medicine. However, the absence at the date of application of a single satisfactory theory linking the chemical structure with biological activity significantly slows down the emergence of new domestic drugs not only in Russia, but throughout the world.

For the first time, the applicant has obtained compounds of a new class, previously unknown from the prior art and having no analogues in the world. After the applicant conducted biological tests on live cultures of balantidia in pigs, highly encouraging results were obtained. In addition, the claimed compounds, according to TG-DSC (thermogravimetry and scanning calorimetry), are thermally stable when heated to 200°C without decomposition and weight loss and withstand sterilization and autoclaving.

The applicant did not identify any structural analogues of the claimed compounds with antibalantidiosis activity from the examined prior art.

Based on the synthesis of the claimed compounds, it is possible to create dosage forms for the prevention and treatment of balantidiasis in pigs, which can find application in veterinary medicine.

Balantidiosis is a widespread disease of pigs on agricultural farms, the causative agent of which is the ciliate Balantidium coli , which lives mainly in the large intestine of pigs [https://ru.wikipedia.org/wiki/Balantidiosis]. In addition to pigs, other animals, as well as humans, also suffer from balantidiasis. The disease occurs with symptoms of catarrhal colitis or catarrhal-hemorrhagic enterocolitis, accompanied by diarrhea, emaciation, and blood is found in the stool. Animals lie down and refuse food. Weight loss usually continues after treatment. The disease lasts from three weeks to two months, often until complete exhaustion. The diagnosis is made by clinical signs and the results of examination of fecal samples, where a large number of motile balantidia and cysts are found.

Treatment tactics for balantidiasis include destroying the pathogen, removing intoxication and maintaining the general condition of the animal’s body. An analysis of the state of the art conducted by the applicant showed that a number of drugs are known for the treatment of balantidiasis.

Thus, the invention is known under patent RU No. 2032415 “Method for the prevention and treatment of balantidiasis in pigs”, the essence is a method for the prevention and treatment of balantidiasis in pigs, including giving biologically active substances to piglets before weaning from the sow, characterized in that the administration of the biologically active substance is carried out for three days before weaning from the sow 2 times a day, and the biologically active substance in a dose of 0.3-0.5 g/kg of animal weight is dissolved in 20-30 ml of distilled water and given together with trichopolum in a dose of 0.2-0, 5 g per head. The method according to claim 1, characterized in that a preparation of plant origin is used as a biologically active substance, including a plant extract, for example alfalfa hay, containing soluble metal salts, mg/kg of plant mass: Mo 8.0; Va 10.0; Rv 20.0; V 1.0; Cz 0.5; Zn 200.0; Fe 300.0; Sn 40.0.

In addition, from the description of the known invention it was revealed that for the treatment of balantidiasis the following is usually used:

Orasol in dose: animals 2-3 months. 0.1-0.2; 3-4 months 0.2-0.3; 4-8 months 0.3-0.4; 8-12 months, 0.4-0.5; over 12 months 0.5-0.7;

Tilan is prescribed at a dose of 0.00125 g/kg 2 times a day for three days in a row, after a three-day break the course of treatment is repeated. The drug is mixed in water for 20 minutes and then mixed with food;

Metronidazole is given to piglets at a dose of 0.25 g 2 times a day for three days in a row; after 3-7 days repeat 2-3 times;

vetdipasfen for the treatment of piglets up to 30 days is used in a dose of 0.125 g from 31 days to 60 days 0.25 g, from 61 to 120 days 0.375 g and older than 120 days 0.725 g daily, 1 time per day for three days in a row;

furazolidone is prescribed at a dose of 0.01 g/kg 3 times a day for 3-5 days;

Iodinol is recommended for 4-6 month old piglets, 20-25 ml per dose, 2 times a day for 7-10 days with a small portion of feed;

The disadvantage of known drugs for the treatment of balantidiasis is:

- development of high resistance, since long-term treatment with these drugs for many years causes parasites to become addicted to it;

- have a high cost.

The claimed compounds were not identified from the examined prior art.

The technical result of the claimed technical solution is to expand the arsenal of means for the specified purpose by creating compounds of a new generation - aniline-substituted derivatives of 5-nitro-4,6-dichlorobenzofuroxan and 4,6-dinitro-5,7-dichlorobenzofuroxan (1-31) of general formula I , having antibalantidiosis activity in low concentrations (0.001 wt.%) and thermal stability - up to 180-200 ° C according to the TG-DSC method.

Moreover, the claimed compounds are low in cost.

The essence of the claimed technical solution is aniline-substituted derivatives of nitrobenzofuroxans 1-2, 6-17, 20, 22-23, 25, 27, 29-31 of general formula I :

I (1-2,6-17,20,22-23,25,27,29-31), where:

The use of aniline-substituted nitrobenzofuroxan derivatives of general formula I (1-31) as antibalantidiosis agents:

I (1 – 31), where:

The claimed technical solution is illustrated in Figure 1 - Figure 5.

Figure 1 shows Table 1 containing the characteristics of the claimed compounds ( 1-31 ) obtained experimentally.

Figure 2 shows Table 2, which shows the antibalantidiosis activity of the claimed compounds ( 1-31 ) of general formula I.

In FIG. Figure 3 shows the TG-DSC curve for 5,7-bis((4-bromophenyl)amino)4,6-dinitrobenzofuroxan (4).

In FIG. Figure 4 shows the TG-DSC curve for 6-chloro-4-(2,3-dichlorophenylamino)-5-nitrobenzofuroxan (23).

In FIG. Figure 5 shows the TG-DSC curve for 6-chloro-4-(3,5-dichlorophenylamino)-5-nitrobenzofuroxan (29).

TG – thermogravimetry, DSC – differential scanning calorimetry. The applicant explains that the inscriptions in Fig. 3 - Fig. 5 are performed automatically by a device - a synchronous microthermal analyzer; when taking curves, they are not subject to editing.

Next, the applicant provides a description of the claimed technical solution.

The declared technical result is achieved by obtaining the claimed compounds 1 – 31 of general formula I.

Characteristics of the starting reagents:

– starting amines based on aniline are commercial products: 4-iodaniline, 4-fluoroaniline, 4-bromoaniline, 2,3-dibromoaniline, 2,4-dibromoaniline, 2,5-dibromoaniline, 3,4-dibromoaniline, 3,5- dibromoaniline, 2,4,6-tribromoaniline, 3-nitroaniline, 4-chloroaniline, 2,3-dichloroaniline, 2,5-dichloroaniline, 3,4-dichloroaniline, 3,5-dichloroaniline, 2,4,6-trichloroaniline;

– 4,6-dinitro-5,7-dichlorobenzofuroxan (DNDHBF) is obtained according to a known method, described, for example, in [Yusupova L. M., Spatlova L. / Optimization of the synthesis of 5,7-dichloro-4,6-dinitrobenzofuroxan / / Bulletin of Kazan Technological University, 2011, p.49-56];

– 5-nitro-4,6-dichlorobenzofuroxan (NDCBF) is obtained according to a known method, described, for example, in [Mukhametshina A.M., Yusupova L.M., Khuziakhmetova A.N. / Optimization of the synthesis of 5-nitro-4,6-dichlorobenzofuroxan with quality control of starting materials, intermediate and final reaction products // Kazan National Research Technological University, June 11, 2016] [https://izron.ru/articles/problemy- meditsiny-v-sovremennykh-usloviyakh-sbornik-nauchnykh-trudov-po-itogam-mezhdunarodnoy-nauch/sektsiya-52-farmatsevticheskaya-khimiya-farmakognoziya-spetsialnost-14-04-02/optimizat-siya-sinteza-5-nitro- 4-6-dikhlorbenzofuroksana-s-kontrolem-kachestva-iskhodnogo-syrya-prome/].

Next, the applicant describes the receipt of compounds 1 – 31 formulas I generally.

The claimed compounds 1 – 31 of general formula I are obtained by the reaction of starting amines based on aniline with 4,6-dinitro-5,7-dichlorobenzofuroxan or 5-nitro-4,6-dichlorobenzofuroxan.

To do this, to a solution of 4 mmol of 5-nitro-4,6-dichlorobenzofuroxan or 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of purified ethanol, add dropwise a solution of 16 mmol of the corresponding starting aniline-based amine in 50 ml of purified ethanol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the synthesized compounds are shown in Table 1 in Figure 1.

Next, the applicant provides examples of the implementation of the claimed technical solution.

Example 1. Preparation of 5,7-bis(4-iodophenylamino)-4,6-dinitrobenzofuroxan ( 1 ) from 4-iodaniline and 4,6-dinitro-5,7-dichlorobenzofuraxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol add a solution of 3.5 g (16 mmol) of 4-iodoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (1) are shown in Table 1 in Figure 1.

Example 2. Preparation of 5,7-bis(4-fluorophenyl)amino)-4,6-dinitrobenzofuroxan ( 2 ) from 4-fluoroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

A solution of 1.78 g (16 mmol) of 4-fluoroaniline in 50 ml of ethyl alcohol is added dropwise to a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound ( 2 ) are shown in Table 1 in Fig. 1.

Example 3. Preparation of 6-chloro-4-(4-fluorophenylamino)-5-nitrobenzofuroxan ( 3 ) from 4-fluoroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 5-nitro-4,6-dichlorobenzofuroxan 1.0 g (4 mmol) in 50 ml of ethyl alcohol add 0.89 g (8 mmol) of 4-fluoroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound ( 3 ) are shown in Table 1 in Figure 1.

Example 4. Preparation of 5,7-bis(4-bromophenylamino)-4,6-dinitrobenzofuroxan ( 4 ) from 4-bromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

A solution of 2.75 g (16 mmol) of 4-bromoaniline in 50 ml of ethyl alcohol is added dropwise to a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound ( 4 ) are shown in Table 1 in Figure 1.

Example 5. Preparation of 4-(4-bromophenylamino)-6-chloro-5-nitrobenzofuroxan ( 5 ) from 4-bromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 1.38 g (8 mmol) of 4-bromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The precipitate of the target product 5 is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound ( 5 ) are shown in Table 1 in Figure 1.

Example 6. Preparation of 5,7-bis(2,3-dibromophenylamino)-4,6-dinitrobenzofuroxan(6) from 2,3-dibromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 4.02 g (16 mmol) of 2,3-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (6) are shown in Table 1 in Figure 1.

Example 7. Preparation of 6-chloro-4-(2,3-dibromophenylamino)-5-nitrobenzofuroxan ( 6 ) from 2,3-dibromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 5-nitro-4,6-dichlorobenzofuroxan 1.0 g (4 mmol) in 50 ml of ethyl alcohol add 2.01 g (8 mmol) of 2,3-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (7) are shown in Table 1 in Figure 1.

Example 8. Preparation of 5,7-bis(2,4-dibromophenylamino)-4,6-dinitrobenzo-furoxan ( 7 ) from 2,4-dibromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 4.01 g (16 mmol) of 2,4-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (8) are shown in Table 1 in Figure 1.

Example 9. Preparation of 6-chloro-4-(2,4-dibromophenylamino)-5-nitrobenzofuroxan ( 7 ) from 2,4-dibromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.01 g (8 mmol) of 2,4-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (9) are shown in Table 1 in Fig. 1.

Example 10. Preparation of 5,7-bis(2,5-dibromophenylamine)-4,6-dinitrobenzo-furoxan ( 7 ) from 2,5-dibromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 4.01 g (16 mmol) of 2,5-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (10) are shown in Table 1 in Fig. 1.

Example 11. Preparation of 6-chloro-4-(2,5-dibromophenylamino)-5-nitrobenzo-furoxan (11) from 2,5-dibromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.01 g (16 mmol) of 2,5-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (11) are shown in Table 1 in Fig. 1.

Example 12. Preparation of 5,7-bis(3,4-dibromophenylamino)-4,6-dinitrobenzo-furoxan ( 7 ) from 3,4-dibromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 4.01 g (16 mmol) of 3,4-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (12) are shown in Table 1 in Fig. 1.

Example 13. Preparation of 6-chloro-4-(3,4-dibromophenylamino)-5-nitrobenzo-furoxan (13) from 3,4-dibromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.01 g (8 mmol) of 3,4-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (13) are shown in Table 1 in Fig. 1.

Example 14. Preparation of 5,7-bis(3,5-dibromophenylamino)-4,6-dinitrobenzofuroxan (14) from 3,5-dibromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 4.01 g (16 mmol) of 3,5-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (14) are shown in Table 1 in Fig. 1.

Example 15. Preparation of 6-chloro-4-(3,5-dibromophenylamino)-5-nitrobenzo-furoxan (15) from 3,5-dibromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 2.01 g (8 mmol) of 3,5-dibromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (15) are shown in Table 1 in Fig. 1.

Example 16. Preparation of 5,7-bis(2,4,6-tribromophenylamino)-4,6-dinitrobenzofuroxan (16) from 2,4,6-tribromoaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 5.28 g (16 mmol) of 2,4,6-tribromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (16) are shown in Table 1 in Fig. 1.

Example 17. Preparation of 6-chloro-5-nitro-4-(2,4,6-tribromophenylamino)-benzofuroxan (1 7 ) from 2,4,6-tribromoaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 2.54 g (8 mmol) of 2,4,6-tribromoaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (17) are shown in Table 1 in Fig. 1.

Example 18. Preparation of 4,6-dinitro-5,7-bis(3-nitrophenylamino)benzofuroxan (18) from 3-nitroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.21 g (16 mmol) of 3-nitroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (18) are shown in Table 1 in Fig. 1.

Example 19. Preparation of 6-chloro-5-nitro-4-(3-nitrophenylamino)benzofuroxan (19) from 3-nitroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 1.10 g (8 mmol) of 3-nitroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (19) are shown in Table 1 in Fig. 1.

Example 20. Preparation of 5,7-bis(4-chlorophenylamino)-4,6-dinitrobenzofuroxan (20) from 4-chloroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.04 g (16 mmol) of 4-chloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (20) are shown in Table 1 in FIG. 1.

Example 21. Preparation of 6-chloro-4-(4-chlorophenylamino)-5-nitrobenzofuroxan (21) from 4-chloroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 1.02 g (8 mmol) of 4-chloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (21) are shown in Table 1 in Fig. 1.

Example 22. Preparation of 5,7-bis(2,3-dichlorophenylamino)-4,6-dinitrobenzofuroxan (22) from 2,3-dichloroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.59 g (16 mmol) of 2,3-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (22) are shown in Table 1 in Fig. 1.

Example 23. Preparation of 6-chloro-4-(2,3-dichlorophenylamino)-5-nitrobenzofuroxan (23) from 2,3-dichloroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 1.3 g (8 mmol) of 2,3-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the obtained compound (23) are shown in Table 1 in Fig. 1.

Example 24. Preparation of 5,7-bis(2,5-dichlorophenylamino)-4,6-dinitrobenzofuroxan (24) from 2,5-dichloroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 2.59 g (16 mmol) 2,5-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (24) are shown in Table 1 in FIG. 1.

Example 25. Preparation of 6-chloro-4-(2,5-dichlorophenylamino)-5-nitrobenzofuroxan (25) from 2,5-dichloroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 1.3 g (8 mmol) of 2,5-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (25) are shown in Table 1 in FIG. 1.

Example 26. Preparation of 5,7-bis(3,4-dichlorophenylamino)-4,6-dinitrobenzofuroxan (26) from 3,4-dichloroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol, add 2.59 g (16 mmol) of 3,4-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (26) are shown in Table 1 in FIG. 1.

Example 27. Preparation of 6-chloro-4-(3,4-dichlorophenylamino)-5-nitrobenzofuroxan (27) from 3,4-dichloroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 1.3 g (8 mmol) of 3,4-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (27) are shown in Table 1 in FIG. 1.

Example 28. Preparation of 5,7-bis(3,5-dichlorophenylamino)-4,6-dinitrobenzofuroxan (28) from 3,5-dichloroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 2.59 g (16 mmol) of 3,5-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (28) are shown in Table 1 in FIG. 1.

Example 29. Preparation of 6-chloro-4-(3,5-dichlorophenylamino)-5-nitrobenzofuroxan (29) from 3,5-dichloroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 1.3 g (8 mmol) of 3,5-dichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (29) are shown in Table 1 in FIG. 1.

Example 30. Preparation of 4,6-dinitro-5,7-bis(2,4,6-trichlorophenylamino)-benzofuroxan (30) from 2,4,6-trichloroaniline and 4,6-dinitro-5,7-dichlorobenzofuroxan.

To a solution of 1.2 g (4 mmol) of 4,6-dinitro-5,7-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 3.14 g (16 mmol) of 2,4,6-trichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (30) are shown in Table 1 in FIG. 1.

Example 31. Preparation of 6-chloro-5-nitro-4-(2,4,6-trichlorophenylamino)-benzofuroxan (31) from 2,4,6-trichloroaniline and 5-nitro-4,6-dichlorobenzofuroxan.

To a solution of 1.0 g (4 mmol) of 5-nitro-4,6-dichlorobenzofuroxan in 50 ml of ethyl alcohol add 1.57 g (8 mmol) of 2,4,6-trichloroaniline in 50 ml of ethyl alcohol.

The resulting solution is stirred at room temperature for 12 hours, then incubated for 24 hours. The resulting precipitate of the target product is filtered off, washed with ethyl alcohol and diethyl ether, and dried in vacuum.

The yield and characteristics of the resulting compound (31) are shown in Table 1 in FIG. 1.

Example 32. Study of the thermal stability of the claimed compounds of the general formula I .

The applicant studied the thermal stability of the claimed compounds of general formula I by thermogravimetry and scanning calorimetry (TG-DSC). The thermal stability was studied using a synchronous microthermal analyzer STA 449C Jupiter (Netzsch, Germany) coupled with a quadrupole mass spectrometer QMS403C Aeolos (Netzsch, Germany); the heating rate of the sample was 10 deg/min in an argon environment.

As a result of the research, it was revealed that the melting temperatures of the claimed compounds (1-31) of general formula I are up to 180-200°C, which indicates their high thermal stability.

As an example, the applicant presents TG-DSC curves for compounds 4 (Figure 3), 23 (Figure 4), 29 (Figure 5) of formula I.

From the TG-DSC analysis curves it can be seen that the given compounds 4, 23 and 29 of formula I indeed have high thermal stability with corresponding melting points of 197.2°C, 184.3°C and 187.2°C, respectively, which makes it is possible to sterilize them at 100°C.

Example 33. Study of the antibalantidiosis activity of the claimed compounds (1-31) of the general formula I .

Studies of the anti-balantidiasis activity of the claimed compounds (1-31) of general formula I were carried out on pigs of various age groups spontaneously infected with balantidiasis. As a control, an experiment was conducted without administering the declared compounds to pigs.

Before the start of the experiment, in order to identify balantidia in the body of pigs, they were examined scatologically under a microscope using well-known methods: the native smear method [https://dpo-ilm.ru/materials/76/158?ysclid=l55s94uz0192694919] and the Darling method [https:// www.zoovet.ru/stati/slovar-veterinarnykh-terminov/metod_darlinga/?ysclid=l55s849pbh915661123].

At the same time, in order to better differentiate cysts and vegetative forms of balantidia (trophozoites), native smears were tinted with Lugol’s solution.

As a result of the study, balantadiasis was detected in all pigs, the results are shown in Table 2 in Figure 2.

To conduct the study, vegetative forms of balantidia (trophozoites) were cultivated from the feces of spontaneously infected pigs and the antibalantidia activity of the claimed compounds (1-31) of general formula I was studied on them and cysts.

To do this, vegetative forms of balantidia were grown in a sterile Erlenmeir flask (1 g of feces per 200 ml of tap water that had settled for 7 days) at a temperature of 23°C in the dark for 20 days. The resulting suspension with live balantidia and cysts, while stirring, was distributed into 9 ml of 93 sterilized tubes with caps and examined for the number of trophozoites and cysts in native smears under a microscope using a well-known method [Pershin G.N. Methods of experimental chemotherapy. – M.: Medicine, 1971. – 245 p.].

The results are shown in Table 2 of Figure 2, column “before administration of compound 1 - 31 ”. Moreover, in each of the 93 experiments (3 experiments for each compound), 3 parallel measurements were carried out - the number of parasites in the field of view of the microscope was successively measured three times under a microscope: the minimum and maximum number is reflected in Table 2 - the “from and to” interval.

Then, to establish the antibalantidiosis activity of the claimed compounds, their solutions at concentrations of 0.1 wt.%, 0.01 wt.%, 0.001 wt.% were prepared, and the original 1 wt.% solutions were first prepared. Then, into each tube (9 ml in each tube) with the initial number of trophozoites and cysts established as described above, the calculated amount of the prepared 1 wt.% solution of each test compound 1-31 was slowly added to ensure the creation of exact concentrations in each tube , namely:

to create a 0.1 wt.% concentration, 1 ml of a 1 wt.% solution was added dropwise,

to create a 0.01 wt.% concentration, 0.1 ml of a 1 wt.% solution was added dropwise,

to create a 0.001 wt.% concentration, 0.01 ml of a 1 wt.% solution was added dropwise.

Then, exactly 30 minutes later (using a stopwatch), the number of cysts and trophozoites of balantidia in the field of view of the microscope in each test tube was measured.

The results are shown in Table 2 of Figure 2, column “after administration of compounds 1-31”. Moreover, in each of the 93 experiments, 3 parallel measurements were also carried out.

From the results given in Table 2, it is clear that the claimed compounds (1-31) of general formula I showed high antibalantidiosis activity against the background of their 30-minute exposure to trophozoites and cysts at low concentrations - up to 0.001 wt.%.

Thus, from the above we can conclude that the applicant has achieved the stated technical result , namely: the arsenal of means for this purpose has been expanded by creating new generation compounds - aniline-substituted derivatives of 5-nitro-4,6-dichlorobenzofuroxan and 4,6-dinitro-5 ,7-dichlorobenzo-furoxan (1-31) of general formula I , possessing antibalantidiosis activity in low concentrations (0.001 wt.%) and thermal stability - up to 180-200°C according to the TG-DSC method.

Moreover, the claimed compounds have a low cost, since they are synthesized from inexpensive starting reagents using known standard methods.

Claims (59)

1. Aniline-substituted derivatives of nitrobenzofuroxans 1-2, 6-17, 20, 22-23, 25, 27, 29-31 of general formula I : , Where: 2. The use of aniline-substituted nitrobenzofuroxan derivatives of general formula I (1-31) as antibalantidiosis agents: , Where: