RU2459813C1 - N-(2-thiazolyl)amide of 3-bromo-2,4-dioxo-4-phenyl butanoic acid, having antimicrobial activity - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry and specifically to novel biologically active substances of the class of N-heterylamides of 4-aryl-3-halo-2,4-dioxobutanoic acids. The compound is N-(2-thiazolyl)amide 3-bromo-2,4-dioxo-4-phenyl butanoic acid, having antimicrobial activity, of formula

(1).

EFFECT: novel derivative of 4-aryl-3-halo-2,4-dioxobutanoic acid, having marked antimicrobial activity, as well as low toxicity.

1 tbl, 1 ex

Description

The invention relates to the field of organic chemistry, to new biologically active substances of the class of N-heterylamides of 4-aryl-3-halogen-2,4-dioxobutanoic acids, namely to N- (2-thiazolyl) amide 3-bromo-2,4- dioxo-4-phenylbutanoic acid (1) of the formula:

possessing antimicrobial activity, which suggests its use in medicine as an antimicrobial drug. The closest analogue in structure and action of the claimed compound is N- (2-pyridyl) amide 4-phenyl-3-bromo-2,4-dioxobutanoic acid (2) [Amides and hydrazides of acylpyruvic acids. Communication 9. Synthesis, antimicrobial and analgesic activity of substituted amides of 4-aryl-3-halogen-2,4-dioxobutanoic acids / E. N. Kozminykh, A. O. Belyaev, E. S. Berezina [et al.] // Chem.-farm. journal - 2002. - T.36, No. 12.- P.9-11] formulas:

Structural analog 2 has low antimicrobial activity. The antimicrobial drug chlorhexidine [1,6-di- (4-chlorophenylguanido) hexane] (3), which is widely used in medical practice and is an analogue in action, was chosen as the reference standard [Mashkovsky M.D. Medicines. - 15th ed., Revised., Rev. and add. - M.: Publishing House New Wave LLC, 2005. - S. 935-936].

The objective of the invention is to search for a series of N-heterylamides 4-aryl-3-halogen-2,4-dioxobutanoic acids substances with a pronounced antimicrobial effect and low toxicity.

The problem is achieved by obtaining N- (2-thiazolyl) amide 3-bromo-2,4-dioxo-4-phenylbutanoic acid (1), which has antimicrobial activity.

The claimed compound 1 is synthesized by the interaction of 4-bromo-5-phenyl-2,3-dihydrofuran-2,3-dione (4) with 2-aminothiazole at an equimolar ratio of reactants in anhydrous carbon tetrachloride at a temperature of 20-25 ° C, followed by isolation the target product by known methods according to the scheme:

Preparation Example 1 of Compound 1. To a suspension of 2.53 g (0.01 mol) of 4-bromo-5-phenyl-2,3-dihydrofuran-2,3-dione (4) in 20 ml of anhydrous carbon tetrachloride, solution 1 was added. 0 g (0.01 mol) of 2-aminothiazole in 30 ml of anhydrous carbon tetrachloride is stirred until the reagent is completely dissolved. The reaction mixture was cooled to 0 ° C, the precipitate formed was filtered off, recrystallized from benzene and dried. Yield 2.98 g (81%). Mp 208-210 ° C. Found,%: C 44.16; H 2.51; Br 22.70; N, 7.89%. C ₁₃ H ₉ BrN ₂ O ₃ S. Calculated,%: C 44.21; H 2.57; Br 22.62; N, 7.93%.

IR spectrum (Specord M80, liquid paraffin, v, cm ^-1 ): 3220ш (NH), 1750, 1700, 1680, 1620 (C ² = O, C ⁴ = O, CO NH, C = C, C = N) . ¹ H NMR spectrum (Bruker DRX 500, DMSO-d ₆ , HMDS, δ, ppm): 6.77 s (1H, C ³ H), 6.86-7.53 m (7H, C ₆ H ₅ , 2CH), 9.07 s (1H, NH).

The inventive compound 1 is a colorless crystalline substance, soluble in dioxane, dimethyl sulfoxide, sparingly soluble in benzene, insoluble in water and alkanes.

The determination of bacteriostatic activity was carried out by the method of two serial dilutions in a liquid nutrient medium [Guide to the experimental (preclinical) study of new pharmacological substances / Fisenko V.P. (ed.). - M .: IIA Remedium, 2000. - S.264-273]. For all studied compounds, MICs (minimum inhibitory concentrations) were determined for museum strains of microorganisms obtained by the State Research Institute of Standardization and Control of Medical Biological Preparations named after L.A. Tarasevich: St. aureus 906 and E. coli 1257. Crops were made in meat and peptone broth pH 7.0 with different concentrations of the test compounds. The cultures were grown in test tubes on a beveled agar medium (meat peptone agar). An 18-20 hour culture was used to determine antimicrobial activity. To prepare a working suspension of microbes, the grown culture was washed off with an isotonic sodium chloride solution and the microbial suspension density was set according to the turbidity standard of 5 units. Then, from the obtained microbial suspension (500 million mt / ml), a working solution of bacteria with a concentration of 5 million mt / ml was prepared. This suspension of microbes was introduced in an amount of 0.1 ml into test tubes with serial dilutions of the studied drug. Thus, the microbial load in the determination of PMA was 250,000 mt / ml. The studied compound in an amount of 0.05 g was dissolved in 5 ml of dimethyl sulfoxide; 1 ml of the resulting dilution 1: 100 was combined with 4 ml of meat and peptone broth (1: 500). Next, a series of serial dilutions of the compound with a doubling concentration was prepared.

The results were taken into account after 20 hours of exposure of control and experimental tubes in a thermostat at a temperature of 37 ° C. MIC was determined by the absence of signs of growth on a nutrient medium: the last tube with growth retardation (clear broth) corresponds to the MIC of the drug for this strain. The bacteriostatic effect of the studied compounds was compared with the action of chlorhexidine. The results were processed statistically with the definition of student criterion using statistical programs Windows XP (Excel) and are presented in table 1.

Acute toxicity (LD ₅₀ ) of the claimed compound 1 was determined on 24 white mongrel mice of both sexes weighing 18-22 g with an oral route of administration in the form of a suspension in a 2% starch solution according to the express method of VB Prozorovsky [Prozorovsky VB, Prozorovskaya M.P., Demchenko V.M. Express method for determining the average effective dose and its errors. // Pharmacology and toxicology. - 1978. - No. 4. - S.497-502]. It was found that the LD _{50 of} compound 1 is 4300 mg / kg, therefore, it is less toxic than chlorhexidine. According to the classification of toxicity of drugs, compound 1 belongs 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].

Table 1 Antimicrobial activity and acute toxicity of compound 1 Compound LD ₅₀ , mg / kg MIC, μg / ml MIC / LD ₅₀ St. aureus E. coli St. aureus E. coli one 4300 7.8 31,0 0.0018 0.0072 Chlorhexidine 4000 125 125 0,0313 0,0313

As can be seen from table 1, compound 1 exceeds the antimicrobial activity of chlorhexidine in relation to Staphylococcus aureus 16 times and Escherichia coli - 4 times. The ratio of MIC (μg / ml) to the toxicity of LD ₅₀ (mg / kg) for compound 1 is 0.0018 for staphylococcus and E. coli 0.0072, while in chlorhexidine these indicators are significantly inferior.

Thus, the N- (2-thiazolyl) amide of 3-bromo-2,4-dioxo-4-phenylbutanoic acid (1) exhibits a higher antimicrobial activity compared to the structural analogue and reference standard, and is also low toxic, which makes it possible using it to create new drugs with antimicrobial activity.

Literature

1. Amides and hydrazides of acylpyruvic acids. Communication 9. Synthesis, antimicrobial and analgesic activity of substituted amides of 4-aryl-3-halogen-2,4-dioxobutanoic acids / E. N. Kozminykh, A. O. Belyaev, E. S. Berezina [et al.] // Chem.-farm. journal - 2002. - T.36, No. 12. - S.9-11.

2. Mashkovsky M.D. Medicines. - 15th ed., Revised., Rev. and add. - M .: New Wave Publishing House LLC, 2005. - p. 935-936.

3. Guidance on the experimental (preclinical) study of new pharmacological substances / Fisenko V.P. (ed.). - M .: IIA Remedium. - 2000. - S.264-273.

4. Prozorovsky V. B., Prozorovskaya M. P., Demchenko V. M. Express method for determining the average effective dose and its errors. // Pharmacology and toxicology. - 1978. - No. 4. - S.497-502.

5. Izmerov I.F., Sanotsky I.V., Sidorov K.K. Toxicometry parameters of industrial poisons. - M .: Medicine, 1977. - S.196-197.

Claims (1)

N- (2-Thiazolyl) amide 3-bromo-2,4-dioxo-4-phenylbutanoic acid of the formula:

possessing antimicrobial activity.