RU2320661C2 - 1,4,5,6-tetrahydro-6-oxo-5-(2-piperazinoethyl)-4-phenyl-3-(4-chlorophenyl)pyrrolo[3.4-c]pyrazole dihydrochloride eliciting hypotensive and anti-coagulant activity - Google Patents

Abstract

FIELD: organic chemistry, chemical technology, medicine.

SUBSTANCE: invention relates to 1,4,5,6-tetrahydro-6-oxo-5-(2-piperazinoethyl)-4-phenyl-3-(4-chlorophenyl)pyrrolo[3.4]pyrazole dihydrochloride of the formula (I):

. This compound is synthesized by interaction of 1-(2-piperazinoethyl)-5-phenyl-4-(4-chlorobenzoyl)-3-hydroxy-3-pyrrolin-2-one dihydrochloride with hydrazine hydrate. Synthesized compound can be used in medicine as agent decreasing arterial blood pressure and blood coagulation. Invention provides synthesis of a novel compound not described early that possesses hypotensive and anti-coagulant effect simultaneously.

EFFECT: valuable medicinal properties of compound.

3 tbl, 1 ex

Description

The invention relates to a new biologically active substance of the pyrrolo [3,4-c] pyrazole series, namely to 1,4,5,6-tetrahydro-6-oxo-5- (2-hyperazinoethyl) -4-phenyl-3- ( 4-chlorophenyl) pyrrolo [3,4-c] pyrazole dihydrochloride of the formula:

having hypotensive and anticoagulant activity, which suggests the possibility of using it in medicine as a drug that effectively reduces blood pressure and blood coagulation and thereby has a therapeutic effect and prevents the development of various complications of hypertension.

The closest structural analogue of the claimed compound is 5- (2-aminoethyl) -1,4,5,6-tetrahydro-3-methyl-6-oxo-4-phenylpyrrolo [3,4-c] pyrazole hydrochloride (Kasimova N.N. Synthesis, properties and biological activity of 1-aminoalkyl- and 1-dialkylaminoalkyl-4-acyl-5-aryl-3-hydroxy-3-pyrrolin-2-ones: Diss ... Candidate of Pharmaceutical Sciences / Perm. Pharmacist. Acad. - Perm, 2002. - p.119) of the formula:

which is taken as a prototype and does not have a hypotensive and anticoagulant effect.

Comparison standards are heparin (Mashkovsky M.D. Medicines: Practical benefit. - 15th ed. - M .: “New Wave”, 2005. - p.475), which is used in medical practice and is an analogue of anticoagulant action, and papaverine (ibid., p. 412) of the formula:

which is used in medical practice and is an analogue of the hypotensive effect.

The essence of the invention is the search in a series of pyrrolo [3,4-c] pyrazoles of a compound with pronounced antihypertensive and anticoagulant activity that reduces blood pressure and blood coagulation. This is achieved by the synthesis of 1,4,5,6-tetrahydro-6-oxo-5- (2-piperazinoethyl) -4-phenyl-3- (4-chlorophenyl) pyrrolo [3,4-c] pyrazole dihydrochloride, which has hypotensive and anticoagulant effect.

The inventive compound is obtained by the interaction of 1- (2-piperazinoethyl) -5-phenyl-4- (4-chlorobenzoyl) -3-hydroxy-3-pyrrolin-2-one dihydrochloride with hydrazine hydrate according to the scheme:

An example of obtaining the claimed compounds.

Example

1,4,5,6-Tetrahydro-6-oxo-5- (2-piperazinoethyl) -4-phenyl-3- (4-chlorophenyl) pyrrolo [3,4-c] pyrazole dihydrochloride.

To a solution of 4.99 g (0.01 M) of 1- (2-piperazinoethyl) -5-phenyl-4- (4-chlorobenzoyl) -3-hydroxy-3-pyrrolin-2-one dihydrochloride in 5 ml of glacial acetic acid was added 0.54 ml ( 0.011 M) 98% hydrazine hydrate and boil for 1.5 hours. After cooling, the reaction mixture is evaporated, the residue is recrystallized from ethanol. Yield 1.63 g (33%). Mp:> 310 ° C. Found,%: C 55.79; H 5.25; N 14.11. C ₂₃ H ₂₆ Cl ₃ N ₅ O. Calculated,%: C 55.82; H 5.30; N 14.15.

The inventive compound is a colorless crystalline substance, soluble in water, ethanol, dimethylformamide, dimethyl sulfoxide.

IR spectrum (SPECORD, liquid paraffin, ν, cm ^-1 ): 1703 (CON), 3100 (NH), 3400 (N ⁺ H, N ⁺ H ₂ ).

₁ H-NMR spectrum (MERCURY 300, 300.055 MHz, DMSO-D ₆ , GMDS, δ, ppm): 2.75 (1H, m, C ₍₁₎ H _A H _B ), 3.32 (10H, m, N (CH ₂ ) ₅ ), 3.95 (1H, m, C ₍₁₎ H _A H _B ), 6.07 (1H, s, C ₍₄₎ H), 7.32 (7H, H _arom ), 7.43 (2H, H _prom ), 9.56 (2H, bs, N ⁺ H ₂ ), 14.13 (1H, bs, NH).

The inventive compound and analogue in structure were tested for antihypertensive activity. The experiments were performed on anesthetized medals (400 mg / kg, intraperitoneally) cats. The substances were tested in the same dose of 5 mg / kg, injected dissolved in 3 ml of isotonic sodium chloride solution into the femoral vein for 2 minutes. Blood pressure was measured in the carotid artery by a direct method using a mercury manometer, fixing the pressure level on the kimograph tape at certain intervals. As a reference standard, the well-known antihypertensive drug papaverine hydrochloride was used, which was tested at a dose of 3 mg / kg (1/10 LD ₅₀ ). The results were processed using the Student's coefficient (Sernov L.N., Gatsura V.V. Elements of experimental pharmacology, M., 2000, pp. 313-313).

Table 1
Antihypertensive activity of compound MS-13 at a dose of 5 mg / kg Stat. will show. HELL ref. 5 minutes 15 minutes 30 minutes 60 min 120 min 180 min 240 min 300 min M 114.9 67.2 70.3 71.1 72.6 70.9 70.3 86.6 91.7 m 8.91 10.85 11.38 11.82 9.76 12.37 12.60 12.94 07/13 p - <0.01 <0.01 <0.02 <0.01 0.02 <0.02 > 0.05 > 0.05 p - in comparison with the initial blood pressure

As can be seen from table 1, the claimed compound has a pronounced antihypertensive effect, lowering blood pressure from 5 min after administration (p <0.01), while the antihypertensive effect persists throughout the entire observation time (more than 6 hours). The maximum decrease in pressure is observed 5-15 minutes after administration and is 41.5-38.8%.

An analogue in the structure of activity was not shown.

The results of testing the comparison standard are shown in Table 2, which shows that under the influence of papaverine hydrochloride, blood pressure decreases by a maximum of 34.4% and lasts only 2 minutes.

table 2
Antihypertensive activity of papaverine hydrochloride at a dose of 3 mg / kg (1/10 LD ₅₀ ) Stat. indicator HELL ref. minutes one 2 5 10 fifteen twenty thirty M 112.8 91.2 74.0 101.6 111.6 112.0 111.2 110.8 m 3.49 3.49 5.75 8.48 1.85 3.01 2.48 2.58 p - <0.01 <0.01 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 p - in comparison with the initial blood pressure

The inventive compound and analogue in structure were examined for the presence of anticoagulant activity. The experiments were carried out using a Minilab 701 coagulometer. For the study, citrate (3.8%) blood (9: 1) of the dog was used. The effect of the compounds on blood coagulation was tested at a concentration of 1 mg / ml of blood. A heparin solution was used as a standard for anticoagulant activity, which was tested at a concentration of 1 U / ml of blood. In each series of experiments, eight animals were used. The degree of anticoagulant activity of the compounds was determined by changing the coagulation time of citrate blood in comparison with the control and the standard. The results were processed using Student's coefficient. (Sernov L.N., Gatsura V.V. Elements of experimental pharmacology, M., 2000, p. 312-313). The test results are presented in table 3.

Table 3
The effect on the blood coagulation system of the claimed compound and the reference standard Compound Coagulation time, s % coagulation changes R the control experience 1,4,5,6-Tetrahydro-6-oxo-5- (2-piperazinoethyl) -4-phenyl-3- (4-chlorophenyl) pyrrolo [3,4-c] pyrazole dihydrochloride 34.3 ± 2.18 41.5 ± 2.03 -21.0 <0.05 5- (2-aminoethyl) -1,4,5,6-tetrahydro-3-methyl-6-oxo-4-phenylpyrrolo [3,4-c] pyrazole hydrochloride 45.1 ± 1.69 50.1 ± 2.35 -11.0 > 0.05 Heparin 29.9 ± 0.48 36.6 ± 1.82 -22.4 <0.01

As can be seen from table 3, the claimed compound exhibits a direct anticoagulant effect, as it significantly increases the coagulation time of citrate blood by 30.4%. Its structural analogue does not have a reliable anticoagulant effect. Benchmark heparin slows down coagulation by 22.4%.

Thus, the claimed compound exhibits 2 types of activity - hypotensive and direct anticoagulant. This combination of activities is of great practical importance, because with hypertension, in addition to increasing blood pressure, an increase in blood coagulation is usually observed, which leads to various thromboembolic complications (myocardial infarction, ischemic stroke).

The acute toxicity of the claimed compound was determined on outbred white mice of both sexes weighing 16-18 g. The compound was administered intraperitoneally and intravenously in the form of an aqueous solution at the rate of 0.1 ml per 10 g of animal weight in increasing doses. The results were processed according to Prozorovsky with the calculation of the average lethal dose of LD ₅₀ at P = 0.05 (Prozorovsky, V.B. Rapid method for determining the average effective dose and its error / V. B. Prozorovsky, M. P. Prozorovskaya, V. M. Demchenko // Pharmacol. And Toxicol. - 1978.- T.41, No. 4.- p. 497-502).

It was found that acute toxicity (LD ₅₀ ) of the claimed compound with intraperitoneal administration is 1460.0 (610.4-2734.4) mg / kg, and with intravenous administration - 467.2 (195.3-875.0) mg / kg.

This work was supported by the Russian Foundation for Basic Research (project No. 04-03-96042).

Information sources

1. Kasimova N.N. Synthesis, properties and biological activity of 1-aminoalkyl- and 1-dialkylaminoalkyl-4-acyl-5-aryl-3-hydroxy-3-pyrrolin-2-ones: Diss. ... cand. pharmacist. Sciences / Perm. state pharmacist. Acad. - Perm, 2002 .-- p.119.

2. Mashkovsky M.D. Medicines: Pract. allowance. - 15th ed. - M.: New Wave, 2005 .-- p.475.

3. Ibid., P. 412.

4. Sernov L.N., Gatsura V.V. Elements of experimental pharmacology, M., 2000, p. 312-313.

5. Prozorovsky, VB The express method for determining the average effective dose and its error / V. B. Prozorovsky, M. P. Prozorovskaya, V. M. Demchenko // Farmakol. and toxicol. - 1978. - T.41, No. 4. - p. 497-502.

Claims (1)

1,4,5,6-Tetrahydro-6-oxo-5- (2-piperazinoethyl) -4-phenyl-3- (4-chlorophenyl) pyrrolo [3,4-c] pyrazole dihydrochloride of the formula

possessing hypotensive and anticoagulant activities.