RU2694263C1 - Analgesic and anti-inflammatory agent with antimicrobial activity - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: present invention relates to the use of N-(naphthalen-2-yl)benzamidine of formula I as an analgesic and anti-inflammatory agent with antimicrobial activity.

EFFECT: technical result is an expansion of the analgesic and anti-inflammatory drugs range, in particular, the preparation of an agent having also antimicrobial activity, having low toxicity and exceeding in the above activities medicines used in medical practice.

1 cl, 4 tbl, 4 ex

Description

The invention relates to the field of organic and medicinal chemistry, namely: to the compound from the class "amidine" - N- (naphthalen-2-yl) benzamidine of formula I, which can be used for the synthesis of new heterocyclic compounds and in medicine as a potential analgesic and anti-inflammatory agent with antimicrobial activity.

The compound N- (2-naphthyl) -amidine of structural formula IIIa is known, where R1 is C ₆ H ₅ , identical to the amidine of formula I [ROBEV, S .: NEW SYNTHESIS OF QUINOZALINE AND BENZOQUINOZOLINE DERIVATIVES // TETRAHEDRON LETTERS, vol. 24, no. 40, 1983, pp. 4351-4354].

The method of obtaining compound I was carried out by reacting benzonitrile with naphthalene-2-amine in a molar ratio of 1: 1 in the presence of a catalyst, anhydrous aluminum chloride, taken in an equivalent amount, at a temperature of 160-180 ° С Moreover, benzonitrile and naphthalene-2-amine are first mixed, the mixture is melted, and then anhydrous aluminum chloride is added in portions with stirring, the mixture is quickly brought to 180 ° C and the synthesis is stopped. The reaction mass is poured in a molten form into a solution of hydrochloric acid, filtered off. The filtrate is poured into a solution of sodium hydroxide. The precipitate is filtered off. The precipitate is additionally washed with 96% ethanol.

The method of obtaining N- (naphthalene-2-yl) benzamidine was studied and carried out under laboratory conditions on standard commercial raw materials.

The data of elemental analysis, the yield of the reaction product, the melting point and the value of R _f are given in table. 1, the spectral characteristics of the obtained compounds are given in table. 2

Patent and scientific literature did not reveal the use of N- (naphthalen-2-yl) benzamidine as an analgesic and anti-inflammatory agent with antimicrobial activity.

The closest in pharmacological properties to the proposed remedy is diclofenac (II) possessing analgesic and anti-inflammatory activity. In addition, it is widely used in practice.

The disadvantages of diclofenac include higher toxicity than the proposed connection.

The objective of the invention is to expand the Arsenal of analgesic and anti-inflammatory drugs, the search for an agent that also has antimicrobial activity, has low toxicity and exceeds the drugs used in medical practice for the indicated activities.

This task is achieved by using N- (naphthalene-2-yl) benzamidine (I) as an analgesic and anti-inflammatory agent with antimicrobial activity.

The invention is illustrated by examples of studies of pharmacological properties.

Example 1. Determination of acute toxicity.

The acute toxicity of compound I was determined on nonlinear white mice by males weighing 18–20 g. The animals were divided into groups of equal size and body weight, 10 animals each. A suspension of the compound in a mixture of DMSO: water (1: 5), stabilized by tween-80, was administered intraperitoneally once in a dose range of 50 mg / kg to 1500 mg / kg. The survival of animals was determined by observing after 24 hours and 48 hours from the moment of administration of the test compound. Observation of the animals was carried out within 72 hours. Recorded the development of the main symptoms and the time of death of animals.

The calculation of the average lethal dose (LD ₅₀ ) was performed using the rapid method B. B. Prozorovsky [Prozorovsky VB Statistical processing of pharmacological research results // Psihofarmakol. biol. narkol - 2007. №7, №3-4 - p. 2090-2120] and probit-analysis by the Miller-Tainter method [M.L. Belenky. Elements of quantitative evaluation of the pharmacological effect (2nd ed., Revised and extra.). - l.,: State. publishing house honey lit., 1963. p. 412]. The toxicity of the inventive substance ranges from 950 mg / kg (Table 3). According to the classification of toxicity of drugs, compound I belong to the class of low-toxic substances [Izmerov I.F., Sanotsky I.V., Sidorov K.K. Toxicometry parameters of industrial poisons. - M .: Medicine, 1977. S. 196-197]. It is more than 4 times less toxic to metamizole sodium - the reference drug for analgesic activity (Table 3). And more than 4 times less toxic to diclofenac.

Example 2. Compound I has antimicrobial activity. Determination of the minimum inhibitory concentrations (MIC) was performed by the serial dilution method in the meat-peptone broth against test cultures of microorganisms Escherichia coli (ATCC 25922), Staphylococcus aureus ATCC 6538-P, recommended by State Pharmacopoeia XIII edition. [State Pharmacopoeia of the Russian Federation. XIII edition. Tom. 1. Methods of biological analysis. OFS.1.2.4.0002. Moscow, 2015. 1470 p.], As well as in relation to lower actinobacteria (actinomycetes) Mycobacterium sp. K8 and Corynebacterium glutamicum H1. The test substance is insoluble in water; therefore, 50% aqueous solution of dimethyl sulfoxide (DMSO) was used as a solvent, the minimum inhibiting concentration of which is 12.5% for all test microorganisms. Then, the resulting solution was transferred to the first tube in a volume of 1.0 ml, stirred, and further two-fold dilutions were performed in all tubes of the series. 1.0 ml of the resulting mixture was removed from the last tube. A suspension was prepared by diluting up to 1 × 10 6 cells in 1.0 ml. The microbial load at the same time was 1 × 105 cells / ml. Crops thermostatically in conditions corresponding to the selected culture. At the end of the exposure time, the results were taken into account. The minimum inhibitory concentration of compound I on Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 6538-P) is 125 μg / ml, and on Mycobacterium sp. K8 and Corynebacterium glutamicum H1 are 62.5 µg / ml and 125 µg / ml, respectively. These values are within the limits of the activity of the drug similar in structure, mafenida acetate. His MIC, depending on the type of microorganism, is 30-5000 μg / ml.

Example 3. Determination of analgesic activity.

For the experimental evaluation of analgesic activity, a model of acetic acid writhing in male mice was used. Convulsions in animals caused by intraperitoneal administration of a 3% solution of acetic acid. The experiment was carried out on white non-linear mice-males weighing 15-22 g. For the experiment 3 groups of animals were used, 7 individuals each. A suspension of N- (4-sulfamoylphenyl) benzamidine (I) in a mixture of DMSO and water (1: 5) (tween-80 stabilizer) was administered once, intraperitoneally at a dose of 1/10 LD ₅₀ 40 minutes before the intraperitoneal injection of 3% acetic acid solution . Animals of the control group were injected with a mixture of DMSO: water (1: 5). Metamizole sodium at a dose of 100 mg / kg was used as a reference drug. The time of the onset of convulsions and their number within 20 minutes were recorded [Kharkevich D.A. Pharmacology Tutorial. - 12th ed. - M .: GEOTAR-Media, 2017. - P. 628-640]. The analgesic activity of the claimed substance is higher than the metamizole sodium comparison drug, the test substance is 4 times less toxic (Table 3).

Example 4. Determination of anti-inflammatory activity.

For the experimental evaluation of anti-inflammatory activity, a rat paw formalin edema model was used. In the experiment used white mongrel rats males weighing 200-240 g. Of them were formed groups of 5 individuals each. Only the phlogogenic agent was administered to the control group. Animals of the experimental groups received the study drug and the reference drug, which were injected intraperitoneally 1 hour before the creation of edema. Aqueous 2% formalin solution was injected subplantarly in an amount of 0.1 ml per animal. The studied native solution of N- (4-sulfamoylphenyl) benzamidine was administered intraperitoneally to the rats as a suspension in DMSO: water (1: 5) at a dose of 1/10 of LD ₅₀ (170 mg / kg). The reference drug is diclofenac (25 mg / kg dose).

Experimental procedures were performed on each animal in the following sequence:

1) intraperitoneal injection of the test sample once for 1 hour before the introduction of the phlogogenic substance;

2) measurement of the foot volume of the right hind paw of the animal (initial data);

3) subplantar administration of formalin (0.1 ml of a 2% solution) into the right hind paw of the animal one hour after the last dose of the test sample;

4) measurement of the volume of the foot of the right hind paw of a rat at certain intervals after the administration of the phlogogenic agent (1 hour and 24 hours).

Measurement of paw volume was performed using a glass oncometer by volume of displaced water after immersing the paw in a special tank. The results obtained from each animal were averaged within the group and the percentage depression of inflammation in the experimental group relative to the control was calculated using the following formula:

Where:

- объем лапки, измеренной до введения формалина у животного, получавшего исследуемый препарат;

- the volume of the legs, measured before the introduction of formalin in the animal treated with the investigational drug;

- объем лапки, измеренной через определенный промежуток времени после введения формалина у животного, получавшего исследуемый препарат;

- the volume of the foot, measured after a certain period of time after the introduction of formalin in an animal that received the test drug;

- объем лапки до введения формалина у контрольного животного;

- the volume of the legs before the introduction of formalin in the control animal;

- объем лапки, измеренной через определенный промежуток времени после введения формалина у контрольного животного.

- the volume of the foot, measured after a certain period of time after the introduction of formalin in the control animal.

Anti-inflammatory activity of the claimed substance is higher than the comparison drug diclofenac, the test substance is 4 times less toxic (Table 4).

Thus, N- (naphthalen-2-yl) benzamidine (I) is of low toxicity, has a significantly greater analgesic activity and low toxicity compared with the widely known and used in medicine comparison drug metamizole sodium. In addition, this substance has anti-inflammatory activity and exceeds the comparison drug diclofenac. The values of antimicrobial activity, depending on the type of microorganism, are within the range of activity and higher than the drug mafenide acetate that is similar in structure to the drug.

N- (naphthalen-2-yl) benzamidine of formula (I) can be recommended for use as an analgesic and anti-inflammatory agent with antimicrobial activity.

Claims (3)

The use of N- (naphthalen-2-yl) benzamidine formula I

as an analgesic and anti-inflammatory agent with antimicrobial activity.