Method of thieno (3,2-c)pyridine's new derivatives production

(54) A process for the preparation of new thieno [3,2-c] pyridine derivatives

The invention relates to a process for the preparation of novel thieno [3,2-c] pyridine derivatives which can be used for therapeutic purposes. The novel derivatives prepared by the process according to the invention can be represented by the general formula I

<img file="CS246082B2_D0001.tif" />

0) where

Y is a group

Ri /

N \

R2 where

R1 and R2 independently of one another are hydrogen, straight or branched chain alkyl of 1 to 4 carbon atoms, or form a substituent with the nitrogen atom to which they are attached, a pyrrolidino, morpholine, piperidine or 4-benzylpiperazine radical, and

X is hydrogen, halogen or methyl.

These compounds contain an asymmetric carbon atom and can therefore exist in the form of two enantiomers. The invention relates to a process for the preparation of each of these enantiomers and a mixture thereof.

The invention also relates to a process for the preparation of pharmaceutically acceptable addition salts of said substances with inorganic or organic acids.

The process according to the invention for the preparation of the compounds of the formula I comprises condensing 4,5,6,7-tetrahydrothienol [3,2-c] pyridine of the formula II

<img file="CS246082B2_D0002.tif" />

(A) with α-chlorophenylacetate of formula III

<img file="CS246082B2_D0003.tif" />

where

R represents an alkyl radical of 1 to 4 carbon atoms and

X is as defined above, to form esters of formula Γ

<img file="CS246082B2_D0004.tif" />

in which R and X are as defined above, these esters are saponified to the acid of formula I '

<img file="CS246082B2_D0005.tif" />

X

O) wherein X is as defined above, and this acid is converted, after optional activation, to an amide of formula I by treatment with an amine of formula

Ri /

HN \

Rz kde

R 1 and R 2 are as defined above, α-halogenated esters of the general formula

III can be obtained by known methods according to EL Eliel, Μ. T. Fisk and T. Proeser, Organic Syntheses, Coll. St. IV. J. Wiley and Sons, Inc. New York, 1963, p. 169.

The condensation of tetrahydrothienopyridine with an ester of formula III is carried out in the presence of an alkali metal carbonate, for example potassium carbonate, in an inert solvent, for example dimethylformamide or tetrahydrofuran or 1,2-dimethoxyethane. The reaction is carried out at 80 ° C^:C to the boiling point of the solvent.

The saponification of the obtained esters of the general formula Γ in which R is methyl or ethyl can be achieved with an alkali metal hydroxide, for example sodium or potassium hydroxide in a mixture of water and alcohol at room temperature to the boiling point of the solvent used.

The acid of formula (I) may be activated by treatment with ethyl chloroformate in the presence of a small excess of triethylamine at a temperature of -5 to 0 ° C in an inert solvent such as chloroform, 1,2-dimethoxyethane or tetrahydrofuran.

A mixed anhydride of formula IV is formed

<img file="CS246082B2_D0006.tif" />

f / v) where

X is as defined above, and the anhydride is then treated directly in the reaction mixture with a small excess or amine at 10 ° C to room temperature to directly obtain amides of formula I.

The invention will be illustrated by the following examples:

Example 1 α- (4,5,6,7-tetrahydrothienol [3,2-c] -5-pyridyl) orchlorophenylmethyl acetate (R = —CH3, X = 2-C1), derivative No. 1

31.47 g (0.144 mol) of 2-chloro-o-chlorophenylmethylacetate and 19.82 were added to a solution of 20 g (0.144 mol) of 4,5,6,7-tetrahydro-trithieno [3,2-c] pyridine in 200 ml of dimethylformamide. g (0.144 mol) of potassium carbonate was added and the mixture was heated at 90 DEG C. for 4 hours, then the reaction mixture was cooled to room temperature, the inorganic salts were removed by filtration and the solvent was evaporated.

243082 with water, then extracted with ethyl ether. The ether extracts were washed with water, dried over sodium sulfate and evaporated to a yellow oil which was purified over hydrochloride to give the title product as white crystals, m.p. 130-140 ° C, recrystallized from ethyl acetate / isopropanol. The yield is 45%.

Example 2 α- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) phenylmethyl acetate (R = CI-13, X = H), derivative No. 2

The title compound is obtained as described in Example 1 by alkylation

4.5.6.7-tetrahydrothieno [3,2-c] pyridine by treatment with 2-chlorophenyl methyl acetate.

The hydrochloride of the resulting product is white crystals, m.p. 200 DEG C. after recrystallization from ethanol. Yield 50%. Example 3 α- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) -o-fluorophenylmethyl acetate (R = —CH3, X – 2 — F), derivative No. 3

This title compound can also be obtained by the method of Example 1 by alkylation

4,5,6,7-tetrahydrothenoeno [3,2-c] pyridine by treatment with 2-chloro-o-fluorophenyl methyl acetate.

The hydrochloride of this material is white crystals, which at 100 ° C becomes a pasty mass. Yield 75.5%.

Example 4 α- (4,5,6,7-tetrahydro-thieno [3,2-c] -5-pyridyl) -o-methylphenylethyl acetate (R = —CH2 — CH3, X = 2 — CH3), derivative number 4

The title compound is obtained as described in Example 1 by alkylation of 4,5,6,7-tetrahydrothieno [3,2-c] pyridine with 2-chloro-o-methylphenylethyl acetate.

The hemisulphate is in the form of white crystals, m.p. 188-190 ° C after recrystallization from isopropanol. Yield 54%. Example 5

N, Nd⁵methyl [α- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl)] - o -chlorophenylacetamide

CH3 /

(Y-N ^

CH3

X = 2-C1), derivative No. 11

To a solution of 30 g (0.092 mole) of α- (4,5,6,7-tetrahydro-thieno [3,2-c] -5-pyridyl] -o-chlorophenylacetic acid as the mioinohydrate and 14.24 ml (0.102 mole) of triethylamine in 300 ml of chloroform cooled to -5 to 0 ° C was added dropwise 9.72 ml (0.102 mol) of ethyl chloroformate, after which the temperature was allowed to rise to room temperature and the reaction mixture was stirred for 1 hour. The mixture was evaporated at 10 ° C and dimethylamine (4.57 mL, 0.102 mol) in chloroform (60 mL) was added dropwise, followed by stirring at room temperature overnight.

Water is added, the two phases are separated by decantation, the organic phase is dried over sodium sulphate and evaporated. A colorless resin is obtained which gradually crystallizes.

The resulting product is in the form of white crystals, m.p. 95-100 ° C after recrystallization from isopropyl ether. Yield: 49%.

Example 5a

N- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) -o-chlorophenylacetic acid (Y = OH, x = 2-C1), derivative # 5.

A mixture of 157.9 g of N- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) -O-chlorophenylethyl acetate and 100 ml of sodium hydroxide is heated at reflux for 2.5 hours. of a concentration of 30% in 600 ml of ethanol. After evaporation of the ethanol, the reaction mixture was acidified with glacial acetic acid and extracted with methylene chloride. The organic phase is washed with water, dried over sodium sulphate and then evaporated. After recrystallization from water, the resulting product can be isolated as the monohydrate.

The resulting product is in the form of white crystals which, after recrystallization from water, transforms into a pasty mass at a temperature of 125 ° C. Yield 46%.

Example 6

1 - [(2-chlorophenyl) - (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) acetyl] pyrrolidine

Y =

<img file="CS246082B2_D0007.tif" />

The above compound can be obtained as described in Example 5 by condensation of N- (4,5,6,7-tetrahydrothieno [2,3-c] -5-pyridyl) -o-chlorophenylacetic acid monohydrate with pyrrolidine.

The resulting product is in the form of white crystals, m.p. 130 DEG C. after recrystallization from isopropyl ether. Yield 61.5%.

Example 7

1 - [(2-chlorophenyl) - (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl] acetyl] morpholine (γ X = 2 Cl)

To a solution of 10 g (0.031 mol) of N- (4,5,6,7-tetrathidrothieno [3,2-c] -5-pyridyl) -o-chlorophenylacetic acid as monohydrate and 13.3 g (0.064 mol) of dicyclohexylcarbodiimide in 100 ml of 1,2-dichloroethane, 2.67 g (0.031 mol) of morpholine are added and the mixture is stirred overnight at room temperature. The reaction mixture was evaporated and treated with 2N hydrochloric acid in ethyl ether. The resulting dicyclohexylurea is filtered off, the filtrate is decanted and the aqueous phase is basified by addition of 2N sodium hydroxide and extracted with methylene chloride. The organic phase is washed with water, dried over sodium sulphate and evaporated to a yellow resin which is made over the hemihydrate hydrochloride.

The resulting product is in the form of white crystals, m.p. 215 DEG-225 DEG C. after recrystallization from isopropanol. Yield 71%. Example 8

1 - [(2-chlorophenyl) -4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl] acetyl] piperidine

<img file="CS246082B2_D0008.tif" />

The resulting product is obtained by the method of Example 7 by condensation of (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) -o-chlorophenylacetic acid as the monohydrate with pipetidine.

The product is in the form of white crystals, m.p. 139 DEG C. after recrystallization from isopropanol. Yield 51.5%.

The following compounds were obtained according to Example 8:

(os- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) o-chlorophenylacetamide (Y = -NHz, X = 2-C1), derivative # 15

The resulting product is in the form of white crystals, m.p. 126 DEG -128 DEG C. after recrystallization from a mixture of isopropyl ether and isopropanol. Yield: 46%.

4-Benzyl-1 - [(2-chlorophenyl) - (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl) acetyl) piperazine

<img file="CS246082B2_D0009.tif" />

derivative No. 16

The oxalate is in the form of white crystals, m.p. 178 DEG C. after recrystallization from ethanol. The yield is 82.5%,

Ν, Ν-dimethyl - [N- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl)] fluorophenylacetamide

CHs /

(Y — N \

CHs

X = 2-F), derivative No. 17

The resulting product is in the form of a pale yellow powder, m.p. 125 DEG C. after recrystallization from isopropyl ether / isopropanol. Yield 41%.

N-methyl- [α 1 - (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl)] -o-chlorophenylacetamide (Y = NH-CH 2, X = 2-C1), derivative No 18

The resulting product is in the form of white crystals, m.p. 137 DEG C. after recrystallization from isopropanol. Yield 85.5%.

N-butyl- [α- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl)] -o-chlorophenylacetamide (Y = = NH- (CH 2) 3 —CH 3, X = 2-C1), derivative No. 19

The resulting product is in the form of white crystals, m.p. 101 DEG C. after recrystallization from isopropyl ether. Yield 65%.

Ν, Ν-dimethyl- [os- (4,5,6,7-tetrahydrothieno [3,2-c] -5-pyridyl] phenylacetamide)

CH3 /

(Y = N

CH3

X = H), derivative No. 20

The resulting product is in the form of white crystals, m.p. 138 DEG C. after recrystallization from isopropyl ether. Yield 39%. Ν, Ν-dimethyl - [N - (4,5,6,7-tetrahydrothieino [3,2-c] -5-pyridyl)] - o methylphenylacetamide

CHs /

(Y = N \

CH3

X = 2-CH3), derivative No. 21

The resulting product was in the form of white crystals at 119 ° C after recrystallization from hexane. Yield 15%.

The pharmacological and toxicological results obtained with the compounds according to the invention give data on the toxicity, tolerability and action of the compounds of the formula I, in particular with regard to the inhibition of platelet aggregation and antithrombotic activity.

The compounds of formula (I) may be formulated as a medicament having platelet aggregation inhibitory activity and antithrombotic activity. The pharmaceutical composition will contain as an active ingredient a compound of formula I or a pharmaceutically acceptable acid addition salt thereof with an inorganic or organic acid.

Toxicological tests

The compounds of formula I are well tolerated and have low toxicity.

Tests were conducted for acute chronic, subchronic and delayed toxicity in various animal species, with no local or general adverse reaction, no disturbances or abnormalities of a macroscopic, microscopic or biochemical nature during any of the experiments.

Pharmacological tests

1. Inhibition of platelet aggregation

The experiments were performed on rats given the active ingredients for 3 days, at 4848 hours, 2424 hours, and hodinách2 hours in gum arabic suspension. At time 0, 4 ml of blood was drawn from the jugular vein by the Renaud method in an anesthetized animal. This citrate blood was used for clustering tests.

Group control derivative No. 17 3 X 100 derivative No. 20 3 X 100

b) Measurement of platelet aggregation in collagen

1.5 ml of citrate blood is added to 0.10 ml of a solution containing 10 µg of collagen per ml. The mixture is stirred, platelet counting is performed without interruption.

Reduction of free platelet count i. Platelet aggregation by ADP ml citrate blood is rapidly poured into a small vessel equipped with a magnetic stirrer. After stirring for a few seconds, 0.4 ml containing 0.66 µg adenosine diphosphate (ADP) in 1 ml is poured into the vial. After 90 seconds of mixing, add two 0.5 ml blood samples:

The primary sample is mixed with 0.5 ml of ethylenediaminetetraacetic acid (EDTA) solution in formol, the second sample is mixed with 0.5 ml of EDTA solution.

The addition of EDTA and formol should stabilize the blood and fix the clusters, the addition of EDTA alone should dissolve the formed clusters.

After 10 minutes, the two mixtures were centrifuged for 5 minutes at low speed to separate red blood cells and the platelet-rich plasma supernatant was collected, diluted and the plates counted.

Clustering intensity can be determined according to the number of platelets in

EDTAJormolu__{χ WQ =%} Platelet count of non-clumped platelets in EDTA

The test substance acts by increasing the inhibition of platelet aggregation, the closer the ratio is to 100.

The results of the experiment in which the platelet count is the average of groups of five rats, either experimental or control, are given in Table I below.

Table I

Dose mg / kg Route of Administration The result - 2 + 0 - 11 + 3 - 4 + 1 is monitored as a function of time continuously and allows a curve to be read from which the initial clumping rate can be read as a function of its slope.

The results are the mean of the group of five rats, both experimental and control, and are shown in Table II below.

Table II

<td>Group</td><td>Dose mg / kg</td><td>Method of administration</td><td>Result</td>

<td>control</td><td></td><td> —</td><td> 2,25 + 0,32</td>

<td>derivative No. 11</td><td>3 X 100</td><td> —</td><td> 0,83 + 0,02</td>

<td>control</td><td></td><td> _</td><td> 2,77 + 0,32</td>

<td>derivative No. 14</td><td>3 X 100</td><td> —</td><td> 1,89 + 0,13</td>

<td>control</td><td></td><td> —</td><td> 3,99 + 0,40</td>

<td>derivative No. 17</td><td>3 X 100</td><td> —</td><td> 2,22 + 0,10</td>

<td></td><td></td><td></td><td></td>

<td>control</td><td></td><td> —</td><td> 5,01 + 0,79</td>

<td>derivative No. 21</td><td>3 X 100</td><td>(7'f · = - '* ·;, ·? · -'</td><td> 3,04 + 0,22</td>

<td>control</td><td></td><td>'V * .v ·¹··</td><td> 11,35 + 1,01</td>

<td>derivative No. 18</td><td>3 X 100</td><td> —</td><td> 10,82 + 0,81</td>

c) Measurement of bleeding time

Determination of anti-platelet aggregation efficacy also had to be completed by determining bleeding time.

For this purpose, a modification of the method described in L. Stella, Μ. B. Donatl and G. de Gaetano, Thromb. Res., 1975, 7, 709-716.

The experiments were performed on rats given 65 hours, 41 hours and 17 hours prior to the experiment with the test substance orally in suspension in 10 ml / kg of an aqueous solution of arabic gum at a concentration of 5 θ / o. After introduction into pentobarbital anesthesia, the rat's tail is separated 5 mm from the end. The blood is allowed to flow for 15 seconds. At this time, the blood is initially aspirated so that the aspirating material does not touch the stump.

The effect is obtained when the blood spontaneously stops within one minute.

The results indicate the average bleeding time in seconds for the five rat group in Table III. Obviously, the compounds prolonged the bleeding time and time data longer than 1200 seconds (20 minutes) were no longer counted.

Table III

Dose mg / kg Route of administration Result

Group Control Derivative No. 18 3 X 200 Control Derivative No. 12 3 X 200

600 &gt; 1200 600 &gt; 1 200

2. Antithrombotic efficacy

This activity was measured in inducing experimental thrombosis with silk thread.

The principle of this procedure is the adaptation of the method of experimental thrombosis induced by extracorporeal circulation as described by Teruhiko Umetsu and Kazuko Sanai (Thromb. Haemost., 39, 1, 1978).

In the markotized rat (intraperitoneal injection of pentobarbital, the left jugular vein and the right a. Carotis externa are dissected).

An arteriovenous shunt is formed by one central catheter and two lateral catheters. A natural white silk thread is introduced in the central part and circulation is restored after 20 minutes. After the staple is stopped, the thread is carefully removed and weighed immediately. The weight of the wet silk is determined in advance so that the weight of the precipitate can be determined from the difference.

The test substance is administered 48 hours, 24 hours and 2 hours before the start of blood short-circuiting blood in suspension in 10 ml / kg of 5% arabic gum, controls receive only 5% arabic gum solution.

The results showing the thrombus mass in mg are shown in Table IV below.

245082

Table IV

Group Dose mg / kg Route of administration Thrombus weight Change in% Control Derivative No. 11 3 X 200 Toxicological and pharmacological tests confirm the low toxicity of the compounds of formula I, which are also well tolerated and have potent inhibition of platelet aggregation, moreover having antithrombotic activity. thus, they can be used in both human and veterinary medicine.

The pharmaceutical compositions containing these substances can be for oral administration and are in the form of tablets, dragees, capsules, drops, granules or syrups. They can also be administered rectally in the form of suppositories or parenterally in the form of injectable solutions.

Each unit dose preferably contains from 0.005 to 0.250 g of the compound produced by the process of the invention, the daily dose may be in the range of 0.005 to 1.00 g, depending on the age of the patient and the severity of the disease.

The following are examples of useful pharmaceutical compositions.

1. Tablets

Tablets may be prepared from the following mixture: The active compound in an amount of 0.050 g is mixed with excipients such as lactose, sugar, rice starch, alginic acid or magnesium stearate.

___ (mg) _

35,76 + 1,76

21,38 + 2,92 —40

2. Dragee

Dragee can be obtained by mixing 0.100 g of active ingredient with excipients such as magnesium stearate, corn starch, gum arabic, shellac, sugar, glucose, white wax, carnauba wax, paraffin and the like.

3. Capsule

Capsules can be obtained by mixing 0.100 g of, for example, derivative No. 17 with excipients such as magnesium stearate, corn starch or lactose.

4. Solution for injection

An injectable solution may be obtained by mixing 0.075 g of the active compound with the isotonic solution to give a final volume of 3 ml.

5. Suppositories

Suppositories can be obtained by mixing 0.100 g of derivative # 21 with semisynthetic triglycerides in an amount sufficient to produce one suppository.