DD235866B1 - PROCESS FOR PREPARING N ALPHA (2-NAPHTHYL) -SULFONYLAMINOACYLATED AMIDINOPHENYL ALANISAMIDES - Google Patents

Description

Field of application of the invention

The invention relates to a process for the preparation of Na- (2-naphthyl) -suifonylaminoacylated amidinophenylalaninamides. These compounds are thrombin inhibitors of high specificity and can be used for eliminating the enzymatic activity of thrombin in the determination of other proteolytic activities, including those of thrombin-rich seed proteases, in biological materials and / or be used advantageously as direct anticoagulants

Characteristic of the known technical solution

In addition to their importance as direct anticoagulants, specific inhibitors of the coagulation enzyme thrombin are of importance for a number of laboratory diagnostic methods for the determination of clotting factors by means of chromogenic peptide substrates. The chromogenic peptide substrates are nonspecifically cleaved by enzymes that are active in the blood plasma in addition to the enzyme to be determined or in the course of the determination This is particularly the case with the determination of the coagulation factor Xa or the determination of factors of the preliminary phase of the coagulation based on the factor Xa formed. In these methods, thrombin is often produced in far greater concentration than factor Xa. The result is falsified by non-specific substrate cleavage and a spectrophotometric Determination by clot formation impaired (Aurell, L, P Fnberger, G Karlsson and G Cleason. Thromb Res 11,595 (1977), Fnberger, P and H Vinazzer, Research Results of Transfusion Medicine and Immuno-Hematology, Bd 6 , Ed H Vinazzer, Medicus Verlag GmbH, Berlin 1979)

In the determination of protein C in plasma activation of this coagulation factor by thrombin Before the chromogenic determination of activated protein C, it is necessary to block the enzymatic activity of thrombin

To eliminate unwanted thrombin activities, the natural thrombin inhibitor hirudin (vanWijk, EM, LH Kahle and JW Ten Cate, CIm Chem 26, 855 [1980]) or an antithrombin III-heparin mixture (Bertina, RM, AW Broeksmans and A van Wijngaarden, Thromb Haemostas [Stuttgart] 51, 1 [1984]). These two thrombin inhibitors have the disadvantage that solutions of these proteins are not stable for a long time,

With specific synthetic inhibitors of the Na-substituted 4-amidinophenylalanine amide type (Sturzebecher, J, F Markwardt, G Wagner and B Voigt, Thromb Res 26,221 [1982]) or derivatives of 4-guatidinophenylalanine (Claeson, G, S Gustavsson and G Mattsson , Thromb Haemostas [Stuttgart] 50, 53 (1983), Rosen, S, Scand J Haematol, Suppl 40, 33, 139 [1984]) allows the undesired thrombin activity to be successfully eliminated in t vomogenic test systems. Moreover, inhibitors of this type permit the investigation of the activation kinetics coagulation factors (Svendsen, L, M Brogh, G Lindeberg and K Stokker, Thromb Res 34,457 [1984])

For the use of thrombin inhibitors in the mentioned diagnostic methods, a high specificity of the inhibition is required. The inhibitor constants of the enzyme to be determined and inhibited must be well apart. Furthermore, the preparation must be free from impurities with inhibitory properties Although amidinophenylalaninamides (Wagner, G, B Voigt, H Vieweg, F Markwardt and J St irzebecher, DD-PS 155954) allow in principle to produce substances of the desired type, but the VerlÄhren consuming and the final product is difficult to clean!

Object of the invention

The invention has the aim of thrombin inhibitors from the known class of Na-sulfonylami Amidinophenylalaninamide in an economically advantageous manner and technically easy to produce

to lead loacy I

Explanation of the essence of the invention

The invention has for its object to provide a synthesis route for the preparation of Na-sulfonylaminoc cyherten Amidinophenylalaninamiden the structure I, which is technically easy to implement and disadvantages of previously known synthesis method significantly reduced or eliminated

NH

² <T V-CH> -Ch

In the formula I, the amidino group can be in the m- or p-position, η = 1 to 5, R ¹ = 2-naphthyl, R ² Φ H, R ³ = η-butyl, R ² and R ³ can with the N Atom to which they are attached form a heteroaliphatic ring which may contain more heteroatoms

The procedure of the synthesis consists of reacting a cyanobenzyl halide with an acylaminoacylaminomalonic acid diester, which is treated under reflux conditions with a mixture of glacial acetic acid and HCl. The main reaction product is cyanophenylalanine. Purification by isoelectric separation is different from the procedure in DD. PS 155954 is not necessary because in the following Syntheses chntten impurities can be separated advantageous

After sulfonylaminoacylation, compounds of the formula II in which the cyano group is in the m- or ρ-position are η = 1

bis5 and R ¹ - 2-naphthyl, according to the invention / u implemented a mixed anhydride, the j

-CH-COOH

Nh-CO- (ChJ-NH-SCL-

by treatment with corresponding amines gives amides of structure III, wherein the substituents R have meaning analogous to formula I.

The inventive method has the advantage that the amides are obtained in crystalline form and the eini

, R ² and R ³ and η the

III

separation of

The further reaction is carried out in the known manner thiocarboxamido and Thioimidsaureesterhydi ohalogenide to amide salts of structure I.

The cyanobenzylacylaminomalonic acid diesters are conveniently reacted in a mixture of equal proportions of glacial acetic acid, HCl and HjO under reflux conditions for several hours to give cyanophenylalanines containing small amounts of carboxyphenyldlanines as the major impurity. These impurities or their reaction products can be separated in the following synthesis steps

The preparation of the amides III is expediently carried out by formation of a mixed anhydride m t ζ Β iso-butyl chloroformate and its reaction with amines The resulting amides ei implementation necessary purity

The invention will be explained with reference to an exemplary embodiment

ie for the others

To a mixture of 10.0 g of 4-cyanobenzylbronnid, 11.0g Acetaminomalonsaurediethylester and 0.5g Kl in 60ml abs dioxane is on the boiling water from a 1.2g Na and 50 ml abs. The ethoxide solution is slowly added dropwise with stirring while stirring. The reaction is admixed with about 500 ml H ₂ O. The precipitate obtained is filtered off with suction after 12 h, washed with plenty of H ₂ O and dried 4-Cyanbenzylacetaminomalonsaurediethylester (mp 168-170 ⁰ C, methanol)

12.0 g of this product are in 100 ml of a mixture equal volumes of glacial acetic acid, HCl (3mol / l) and H ₂ O 12h under reflux heated The solvent is distilled off 1 Vak The distillation residue is dried and then washed with ether or from methanol / ether

5.0 g of the product thus obtained are dissolved in 75 ml of NaOH (1 mol / l) and shaken with a solution of 5.5 g of 2-Naphthylsulfonylglycylchlond in ethyl acetate for 3 h. The organic phase is separated, the aqueous alkaline phase extracted with ethyl acetate and then with HCl acidified Na (2-naphthylsulfonylglycyl) -4-cyanophenylalanine is filtered off and recrystallized from methanol (mp 156-158 ⁰ C)

5.0 g of the reaction product thus obtained are suspended in 75 ml of abs of ethyl acetate. The mixture is admixed with 1.6 ml of N-ethylmorpholine and carefully warmed with constant swirling. The solution is mixed and stirred for 20 minutes. The suspension obtained is then treated with 2.5 ml of piperidine and 3 h shaken the precipitate is filtered off with suction and washed with a little methanol Na (2-Naphthylsulfonylglycyl) -4-cyanphenylalanmpiperidid recrystallized from methanol (m.p. 186-188 ⁰ C) A second minor fraction can be recovered by passing the ethyl acetate, the mother liquor concentrated in vacuo 1 becomes

4.0 g of piperidide are dissolved in abs of pyridine and treated with 1 ml of TEA The mixture is saturated with H ₂ S and stored for several days at room temperature It is then stirred into ice / HCI, the precipitate was filtered off with suction, washed with verd HCI and then with HjO and dried (mp 207-209 ⁰ C)

3.0 g of thioamide are suspended in 50 ml of acetone. After the addition of 2.5 ml of methyl iodide, 10 mm are heated under reflux conditions. The hot mixture is filtered and the thiomethylsulfonate completely precipitated and filtered off with suction after cooling with ether. The product may have to be precipitated from methanol / ether (Mp 126-130 ⁰ C)

3.0 g of thioimidic acid ester salt are dissolved in abs of methanol and after addition of an equimolar amount of ammonium acetate heated for 2-3 h at 6O ⁰ C The mixture is filtered and the solution largely concentrated 1 Vak The residue is taken up in abs of methanol and the solution was concentrated again 1 Vak , By addition of ether, Na (2-NaphthylsulfonyrglycyD-4-annidinophenylalaninpiperididhydroiodid completely precipitated It is optionally reprecipitated from methanol / ether

Mp 252-256 ⁰ C. Yield 80% (based on thioimidic acid ester)

Ber C 49.92 H 4.97 N 10.78

Gef C49.37 H 5.12 N 10.92

Analogously, the preparation of Na- (2-naphthylsulfonylglycyl) -3-amidinophenylalaninmorpholidhydroiodid from 3-cyanophenylalanine via Na- (2-naphthylsulfonylglycyl) -3-cyanphenylalanine (mp 161 ⁰ C, methanol / H ₂ 0), the Mischanhydridbildung, Reaction with morphine to give Na-sulfonylaminoacylic acid amide and further reaction via thioamide, thioimidic acid ester salt to amidine salt Yield * 82% (based on thioimidic acid ester)

Ber C 47.93 H 4.64 N 10.75

C 47.68 H 4.72 N 10.57

Claims (1)

Process for the preparation of Na- (2-naphthyl) -sulfonylaminoacylated amidinophenylalaninamides of general formula I - CO- (Ch ^) _n - WH - $ 0, -1 ?. in which the amidino group can be in the m- or p-position, η = 1 to 5, R ¹ = 2-naphthyl, R ² = H and R ³ = η-butyl, and R ² and R ³ with the N-atom to which they are attached, may form a heteroaliphatic ring which may contain and / or be substituted by further heteroatoms, by reacting a cyanobenzyl halide to form a Cyanobenzylacylaminomalonic acid diester and its hydrolysis and decarboxylation in a mixture of glacial acetic acid, HCl and H ₂ O to cyanophenylalanine hydrochloride which is reacted with sulfonylated aminocarboxylic acid halide to give a nasulfonylaminoacylated cyanophenylalanine (II), characterized in that the Na- (2-naphthyl) sulfonylaminoacylated Suspended cyanophenylalanine (II) in an organic solvent such as absolute ethyl acetate, acetonitrile or tetrahydrofuran, treated with an amine such as triethylamine, 1-ethylpobrazine or 4-ethylmorpholine and heated with thorough mixing, after some time the liquid phase separated and with ice cooling with chloroformic acid Iso-butyl ester is added and stirred, the resulting suspension with piperidine or pyrrolidine or morpholm or n-butylamine is added and shaken and the Na- (2-naphthyl) -sulfonylaminoacylierte Cyanphenyialanamid (Hl) separated and in a conventional manner to a Na - (2-naphthyl) -sulfonylam inoacylated amidinophenylalanine amide hydrohalide (I) is reacted.