RU2429225C2 - N-substituted amides of 2-hydroxy-4-oxo-4-(41-chlorophenyl) 2-butenoic acid, exhibiting antimicrobial activity - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a novel biologically active substance, -N-substituted amide of 2-hydroxy-4-oxo-4-(4¹-chlorophenyl) 2-butenoic acid of formula

(I), R=2,6-(CH₃)₂C₆H₃ (Ia); 2,4,6-(CH₃)₃C₆H₂ (Ib).

EFFECT: marked antimicrobial activity and low toxicity.

1 cl, 2 ex, 1 tbl

Description

The invention relates to the field of organic chemistry, to derivatives of acylpyruvic acids, namely to new biologically active substances - N-substituted amides of 2-hydroxy-4-oxo-4- (4 ^1- chlorophenyl) 2-butenoic acid of the formula (I):

R = 2.6- (CH ₃ ) ₂ C ₆ H ₃ (Ià); 2,4,6- (CH ₃ ) ₃ C ₆ H ₂ (Iá);

which can find application in medicine as antimicrobial drugs.

The closest structural analogue of the claimed compounds is N-4-methylphenylamide 2-hydroxy-4-oxo-4- (4 ^1- chlorophenyl) 2-butenoic acid having antimicrobial activity. A well-known structural analogue of the claimed compounds obtained by the interaction of 5- (4 ^1- chlorophenyl) -2,3-dihydro-2,3-fypandione with 4-methylaniline [Belyaev A.O. Amino derivatives of 4-aryl-4-oxo-2-butenoic acids: synthesis, structure, properties and biological activity. Abstract. diss. Cand. Chem. sciences. / Kursk. 2004. - 20 p.].

As a reference standard, we took an antimicrobial drug - dioxidine [Mashkovsky M.D. Medicines M .: New wave, T.2], widely used in medical practice.

The purpose of this invention is the synthesis of previously undescribed N-substituted amides of 2-hydroxy-4-oxo-4- (4 ^1- chlorophenyl) 2-butenoic acid with antimicrobial activity.

This goal is achieved by the known method [Andreichikov Yu.S., Milyutin A.V., Krylova I.V., Saraeva R.F., Dormidontova E.V., Drovosekova L.P., Nazmetdinov F.Ya., Kolla V.E. Synthesis and biological activity of aroylpyruvic acid heterylamides and 5-arylpyrazole-3-carboxylic acids // Chem.-Pharm. - 1990. - T. 24. - No. 7. - S.33-35] N-substituted amides of 2-hydroxy-4-oxo-4- (4 ^1- chlorophenyl) 2-butenoic acid by reaction of 5- (4-chlorophenyl) -2,3-dihydro-2,3- furandion [Igidov N.M., Kozminykh E.N., Sofyina O.A., Shironina T.M., Kozminykh V.O. Synthesis of 1,6-diaryl-3,4-dihydroxy-2,4-hexadiene-1,6-diones from derivatives of 2,3-furandiones. // Chemistry heterocycle. connection 1999. No. 11. S.1466-1475] with 2,6-dimethyl - or 2,4,6-trimethylanilines in toluene:

R = 2.6- (CH ₃ ) ₂ C ₆ H ₃ (Ià); 2,4,6- (CH ₃ ) ₃ C ₆ H ₂ (Iá).

An example of the preparation of the claimed compound Ia

To a solution of 2.09 g (0.01 mol) of 5- (4 ^1- chlorophenyl) -2,3-dihydro-2,3-furandione in 10 ml of toluene, 1.21 g (0.01 mol) of 2,6-dimethylaniline was added and boiled for 5-7 minutes After cooling, the precipitate was filtered off, washed with hexane, and recrystallized from acetonitrile. 1.90 g (58%) of crystalline compound (I) are obtained with T _pl. 143-145 ° C. Found: C, 65.43; H 4.76; Cl 10.83; N, 4.19. C ₁₈ H ₁₆ ClNO ₃ . Calculated: C 65.56; H 4.89; Cl 10.75; N, 4.25. IR spectrum, v, cm ^-1 (crystals): 3344 (CO NH ), 1696 ( CO NH), 1592 (C = C, CO chel.). PMR spectrum, δ, ppm, DMSO-d ₆ : 2.14 s (6H, 2 CH ₃ ); 4.57 s (2H, CH ₂ ); 7.04-8.05 m (8H, CH C ₆ H ₄ , C ₆ H ₃ ), 10.12 br. s (1H, NH)

An example of the preparation of the claimed compound IB

To a solution of 2.09 g (0.01 mol) of 5- (4 ^1- chlorophenyl) -2,3-dihydro-2,3-furandione in 10 ml of toluene was added 1.35 g (0.01 mol) of 2,4,6-trimethylaniline and boil for 5-7 minutes. The precipitate that formed after cooling was filtered off, washed with hexane, and recrystallized from acetonitrile. 1.89 g (55%) of crystalline compound (I) are obtained with T _pl. 168-171 ° C. C ₁₉ H ₁₈ ClNO ₃ . Found: C, 66.38; H 5.28; Cl 10.31; N, 4.07. Calculated: C 66.26; H 5.19; Cl 10.22; N, 4.00. IR spectrum, v, cm ^-1 (crystals): 3288 (CO NH ), 1680 ( CO NH), 1596 (C = C, CO chel.). PMR spectrum, δ, ppm, DMSO-d ₆ : 2.05 s (6H, 2 CH ₃ ), 2.22 s (3H, CH ₃ ), 4.55 s (2H, CH ₂ ), 6 83 s (2H, C ₆ H ₂ ), 7.08 s (1H, CH), 7.56, 7.94 two d (4H, C ₆ H ₄ ,), 10.02 br. s (1H, NH).

The obtained compounds (I a, b) are yellow crystalline substances soluble in dimethisulfoxide, dimethyformamide, insoluble in acetonitrile, acetone, insoluble in hexane and water.

The study of biological activity

Acute toxicity with intraperitoneal administration is determined on white non-linear male mice weighing 18-24 g. The test substance and the reference drug are injected into the abdominal cavity in the form of a solution in 1% starch mucus at the rate of 0.1 ml per 10 g of animal weight in increasing doses. The results are processed according to Prozorovsky with the calculation of the average lethal dose (LD ₅₀ ) at P <0.05 [Prozorovsky V.V., Prozorovskaya M.P., Demchenko V.M. Farmakol. toxicol. T41, No. 4, p. 497-502 (1978)].

The determination of bacteriostatic activity is carried out by the method of double serial dilutions in a liquid nutrient medium [Guide to the experimental (preclinical) study of new pharmacological substances. M., 2000., s.264-273]. For all the studied compounds, IPC is determined for the strains: S. aureus ATCC 6538-P, E. coli ATCC 25922, B. subtilis ATCC 6633, Ps. aeroginosa ATCC 9027, C. albicans NCTC 885-653. Crops are produced in meat and peptone broth, pH 7.0 with various concentrations of the tested compounds. The cultures are grown in test tubes on a beveled agar medium (meat peptone agar, dense Saburo medium). To determine the antimicrobial activity, 18, 20, 48-hour pure cultures of microorganisms are used. To prepare a working suspension of microbes, the grown pure cultures are washed off with isotonic sodium chloride solution and the microbial suspension density is set according to the turbidity standard of 5 units. Next, from the obtained microbial suspension (500 million mt / ml), a working solution of bacteria with a concentration of 5 million mt / ml is prepared. This suspension of microbes is introduced in an amount of 0.1 ml into test tubes with serial dilutions of the studied drugs. Thus, the microbial load is 250,000 mt / ml. The studied compound in the amount of 0.05 g is dissolved in 5 ml of dimethyl sulfoxide, 1 ml of the resulting dilution of 1: 100 is combined with 4 ml of meat-peptone broth or Saburo liquid medium (1: 500). Next, prepare a series of serial dilutions with a half-decreasing concentration.

The results are taken into account after 18-20 hours of exposure of control and experimental tubes in an thermostat at a temperature of 37 ° C for bacteria and after 48 hours at 22 ° C for mushrooms. The minimum inhibitory concentration (IPC) is determined by the absence of signs of growth on a nutrient medium: the last tube with growth retardation (clear broth) corresponds to the IPC of the drug for this strain. The antimicrobial effect is compared with chlorhexidine bigluconate (CGB) [Padeiskaya E.N. Inf. and antimicrobial. therapist., 2001, No. 5, pp. 105-155]. The research results are presented in table 1.

Table 1 Antimicrobial activity (μg / ml) and acute toxicity of compounds Compound B.subtilis Ps.aerogin. S.aureus E.coli C.albic. LD ₅₀ mg / kg 1a 64-128 500-1000 0.25-0.5 1-2 500-1000 2820.0 (2300.0 ÷ 3400.0) 1b 128-250 500-1000 3.9-7.8 7.8-15.6 125-500 1410.0 (1100.0 ÷ 1700.0) Hgb 1-3 10-500 1-2 1-5 7-15 4000

Compounds (Ia, b) have antimicrobial activity against gram-positive and gram-negative microorganisms (MIC 0.25-1000 μg / ml).

According to the classification of toxicity of drugs [Izmerov I.F., Sapotsky I.V., Sidorov K.K. The toxicometry parameters of industrial poisons // M., p .97 (1977)] compounds Ia, b belong to the class of practically non-toxic drugs.

Thus, the N-substituted amides of 2-hydroxy-4-oxo-4- (4 ^1- chlorophenyl) 2-butenoic acid (Ia, b) exhibit pronounced antimicrobial activity and are practically non-toxic. Therefore, the claimed compounds (Ia, b) can find application in medicine as antimicrobial drugs.

Claims (1)

N-substituted amides of 2-hydroxy-4-oxo-4- (4 ^1- chlorophenyl) 2-butenoic acid of the formula

showing antimicrobial activity.