CS228547B2 - Method for the production of pentapeptide - Google Patents

Description

The invention relates to a process for the preparation of pentapeptides of the general formula I,

A — B — Gly — D-E (I) in which

A is a radical of formula (II),

R

where

Z ¹ represents a hydrogen atom, a methyl group or an amidino group,

R 1 represents a hydrogen atom or a C 1 -C 4 alkyl group;

R2 is hydrogen or

R 1 and R 2 together form an ethylene bridge and

R3 represents a hydroxy or alkoxy group having 1 to 4 carbon atoms attached to the 3, 4 or 5 position,

B represents the residue of (D) -tsomeir natural α-amino acids,

D is a radical of formula III,

Z ²

AND

R4 CH2

I - N - CH - CO - (III) in which

R 4 represents a hydrogen atom or a C 1 -C 4 alkyl group;

Z ² is phenyl optionally mono- or di-substituted with halogen, nitro, C 1 -C 4 alkyl or C 1 -C 4 alkoxy; and

E is a radical of formula (IV),

R5 R6

I - N - CH - CH 2 OH (IV) wherein

R 5 is hydrogen or C 1 -C 4 alkyl, and

R e represents a radical of formula - (CH ₂ ) _n -CH ₂ S (O) _p -R ₇ wherein

R7 is C1 -C6 alkyl, n is 0, 1 or 2, and p is 1 or 2, wherein residues A and D have the (L) -configuration, the residue Ema (Dj- or (L) the) configuration and the residue B has the (Dj configuration with the proviso that -11 Z is ¹ hydrogen or methyl, then FU represents a C 3 -C 4 alkyl group, as well as their physiologically hydrolyzable, physiologically acceptable esters and salts and complexes of these pentapeptides and esters.

In describing the polypeptides of the invention as pentapeptides, it should be understood that the amino alcohol moiety of E is considered to be an amino acid derivative.

The term "amidino" refers to a group of the formula

NH

AND

NH 2 —c—.

When Z ¹ represents an amidino group, then R f represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms. When Z ¹ represents a hydrogen atom or a methyl group, then R 4 represents a C 3 -C 4 alkyl group.

The compounds of the formula I according to the invention in which Z ¹ represents a hydrogen atom or a methyl group belong to the class of compounds described in DOS No. 2 702 711 and the equivalent GB patent No. 1 578 873. All compounds produced according to the invention are novel.

As mentioned above, the compounds produced according to the invention show advantageous biological properties, in particular inhibitory activity on luteinizing hormone secretion, and can be used as pharmaceutically active substances.

The E moiety may have either the (LJ- or (Dj-configuration). In the text of the present invention and in the definition of the present invention, the terms "the residue (LJ-amine alcohol)" and "the residue (DJ-S-amine alcohol)" mean such. residues in which the relative configuration corresponds to the configuration of the residues corresponding to (L 1 -a-amino acids and (D 1 -a-amino acids respectively) [wherein the carboxyl group in that residue (L 1 - or (D 1 -amino acids is replaced in each case by -CH 2 OH)) It is to be understood that these radicals may carry an alkyl substituent of 1 to 4 carbon atoms on the nitrogen atom at the 10-position.

In the pentapeptides of formula I, the following meanings of the individual symbols or combinations thereof are preferred:

lj Both R1 and R2 are hydrogen,

R 3 is hydroxy. Most preferably, R 3 occupies position 4 and is especially 4-hydroxy,

3) B is a residue (Dj-isomer of a natural non-aromatic α-amino acid. Most preferably, B is a residue - (Dj-A? -,

4) R 4 represents a C 1 -C 4 alkyl group, for example a methyl group. When R4 represents a C 3 -C 4 alkyl group (both when Z ¹ is hydrogen or methyl, or when Z ^{1 is} amidino J, this is preferably n-piropyl, isopropyl or n-butyl, especially n-propyl,

5) Z ² is preferably a phenyl group, optionally mono- or disubstituted with one or two of the fluoro, chloro and initro group, especially fluoro. Means 11-Z ² substituted phenyl group is preferably mono-substituted phenyl, in particular m- or p-substituted phenyl group. Most preferably, Z ² is phenyl or m- or p-fluorophenyl group, especially a phenyl or p-fiuorfenylovou group,

6.1 R5 preferably represents a hydrogen atom,

6.2 R6 is preferably a radical of formula

CH3 — SO — CH2 — CH2— or ·

CH ₃ —SO 2 —CH 2 —CH 2 -,

6.3 Most preferably, R6 is a radical of formula

CH3-SO-CH2-CH2-a

6.4 The residue E, including the preferred residues within the meaning of the symbol E, as defined in paragraphs 6.1 to 6.3 above, preferably has the (L) -configuration (as defined above). Most preferably, E is -Met (O) -ol, i.e., (L) -methioninol sulfoxide.

The hydroxy groups in the pentapeptides of the formula I, in particular the hydroxy group of the terminal amino-E radical, can be esterified to give the corresponding physiologically hydrolyzable, physiologically acceptable esters, i.e. esters which give the physiologically acceptable acid by hydrolysis.

Suitable esters include, for example, esters of mono- and dicarboxylic acids, in particular esters of carboxylic acids having 2 to 5 carbon atoms, such as acetates, as well as aromatic carboxylic acids, such as benzoates.

The pentapeptides of the formula I and their esters may be in the form of acid addition salts or in the form of complexes. Acid addition salts may be formed with, for example, organic acids, polymeric acids, and inorganic acids. Such acid addition salts include, for example, hydrochlorides and acetates. By "complexes" is meant compounds of a known type, prepared from pentapeptides of the general formula I and their esters by addition of inorganic compounds, for example inorganic salts or hydroxides such as salts of calcium, magnesium, aluminum, cobalt and especially zinc, or addition of polymeric organic substances.

One group of compounds of the invention are the pentapeptides of formula I wherein:

Z ¹ is an amidino group,

B is - (D) -Ala-,

Z ² is phenyl optionally mono- or disubstituted with halogen, nitro, C 1 -C 4 alkyl or C 1 -C 4 alkoxy; and

R 1, R 2, R 5, R 1 and E are as defined above. in Formula I and their acid addition salts and complexes.

A second group of compounds of the invention are the pentapeptides of formula I wherein:

Z ¹ represents a hydrogen atom or a methyl group,

R 1 and R 2 either represent hydrogen atoms or together form an ethylene bridge,

R3 represents a hydroxyl group at the 4-position,

B is - (Dj-Ala-,

R <represents a (C až-C 3) alkyl group (in particular n-propyl, n-butyl and isobutyl),

Z ² represents a phenyl group optionally mono- or disubstituted with one or two substituents selected from the group consisting of halogen atoms, nitro, C 1 -C 4 alkyl and C 1 -C 4 alkoxy, and

E represents the radical -Met (O) -ol, and their acid addition salts and complexes.

The present invention provides a process for the preparation of the compounds described above. These compounds can be prepared by oxidizing a pentapeptide or ester thereof having the sequence shown in Formula I wherein E is a radical of the formula - (CH 2) _n --CH 2 --S - R 7, wherein R 7 is as defined above, to form the corresponding peintapeptide or ester, wherein E is a radical of the formula - (CH 2 J _n - CH 2 - S (O J p - R v) where n, p and R 7 are as defined above, and the pentapeptide or ester thus formed is isolated in the form or in the form of an acid addition salt or complex.

The above reaction can be carried out analogously to the procedure described below in the example. If the preparation of the starting materials is not specifically described, these compounds are either known or can be prepared and purified by methods known per se.

The pentapeptides and esters of the invention, as well as their physiologically acceptable acid addition salts and complexes, exhibit valuable pharmacological properties as evidenced by animal testing. These compounds (in particular inhibit luteinizing hormone secretion and have central nervous system depressant activity, as exemplified by the following assays.

Inhibitory activity on luteinizing hormone secretion; inhibition of ovulation in rats

Adult female rats weighing 200-250 g, with a regular four-day estrole cycle, are maintained under standard conditions [14 hours of light per day from 4.00 to 18.00, 24 ° C and 55 to 60% relative humidity] without restricting food and water intake. The test compound is administered subcutaneously in the preest stage, with the test doses applied once at 13.00 h and then again at 16.00 h. 20 hours after the first dose, the rats are sacrificed, their fallopian tubes are removed and the total number is determined using a microscope. eggs in both fallopian tubes. The evaluation is carried out by judging the inhibition of ovulation only if no egg can be detected. Each dose was tested in five rats.

2. Depressive activity on the central nervous system

This assay is performed by monitoring changes in the spontaneous behavior of mice and rats in accordance with the principles described by J. H. Nodid et al. in "Animal and Clinical Pharmacological Techniques in Drug Evaluation", Chicago, 1964, and in "Psychopharmacologia", 13, 222-257 (Berlin, 1968).

The pentapeptides, esters, salts and complexes described above can be used accordingly

(a) for the treatment of patients with disorders whose etiology is related to or modulated by luteinizing hormone secretion or whose etiology includes physiological regulation of luteinizing hormone secretion, for example in the treatment of prostate hypertrophy or in the treatment of

228347 menopausal syndrome, particularly post-menopausal hot flashes, for example in accordance with the studies described by Tataryn et al. ("Thermo-regulatory mechanisms and thelr Theirapeutic Implications", 4th International Symposium on the Pharmacology of Thermoregulation, Oxford, 1979; publ. Karger, Basel 1980, pp. 202-207, and Cíasper et al. ["Science, 205, 823-825 (1979), and bj as psychopharmaceuticals, for example in the treatment of psychotic conditions.

For both of these uses a) and b), the recommended dose is in the range of 0.1 to 10 mg of pentapeptide or ester thereof, the total dose being administered in several divided doses two to four times daily in unit dosage form, or protrahované forma. Thus, suitable unit dosage forms, for example, for oral administration, contain from 0.025 to 5.0 mg of the pentapeptide or ester mentioned above, or an equivalent amount of a pharmaceutically acceptable salt or complex, together with a solid or liquid pharmaceutical diluent or carrier. These compositions may take the form of, for example, solutions or tablets.

The invention further describes

1] a method of inhibiting luteinizing hormone secretion, in particular a method of treating prostate hypertrophy or menopausal syndrome, in particular post-menopausal hot flashes, and a method of treating psychotic disorders in patients in need of such treatment, comprising administering to said patient an effective amount of pentapeptide or a physiologically hydrolyzable, physiologically acceptable ester, or a physiologically acceptable acid addition salt or complex of such a pentapeptide or ester, and

(2) pentapeptides, esters, acid addition salts and complexes referred to in (1) above. as pharmaceuticals, i.e. for use in the treatment of a human or animal, in particular for use as described in paragraph 1), and

AND

(3) pharmaceutical compositions containing the pentiapeptides, esters, acid addition salts or complexes mentioned in (1) above as active ingredients.

The following common abbreviations are used in the specification, in the examples, and in the definition of the invention:

Met-ol = (L) -methioininol residue of formula OH3SCH2CH2CH (CH2OH) NH-,

Met (Oj-ol = residue (L 1 -methioninol sulfoxide of formula

CH 5 -S [O] -CH 2 CH 2 CH (CH 2 OH j -NH-,

MeTyr = -N-methyl-Tyr-

MeTyr (Bu ¹ ) = -N-methyl-O-tert-butyl-Tyr-,

MePhe = -N-methyl-Phe-, (N-propyl) Phe = -Nm-piropropyl-Phe-, (N-isobutyl) Phe - -N-isobutyl-Phe-, (N-butyl) Phe = -Nn-butyl- Phe-, (N-propyl) Phe (p-Fj = -Nn-propyl-p-fluoro-Phe,

Boc = t-butoxycarbonyl,

Z = benzyloxycarbomyl.

In accordance with the standard nomenclature, the L-configuration is considered for all amino acid residues referred to by the three-letter abbreviations, unless otherwise indicated.

Example 1

^C N-amidino-Tyr- (D) -Ala-Gly- (N-propyl-1) Phe-Met (O-i-ol, hydrochloride salt

1.05 g of N ^and -aimidino-Tyr (D) -Ala-Gly- (N-propyl) Pf-Met-ol hydrochloride are dissolved in 10 ml of acetic acid and oxidized at 20 ° C using 0.15 ml. 11 M hydrogen peroxide After 10 minutes, the product was precipitated with ethyl ether, and the crude product was purified by countercurrent shaking in chloroform / methanol / water (65: 35: 10 v / v) to give the title compound after recrystallization from methanol / ethyl ether. [ _.alpha. ] _D @ ²⁰ = -33.6 DEG (c = 1 in 95% acetic acid).

The starting material used in the above reaction was prepared as follows:

a) H- (N-propyl) Phe-NH-NH-Z-hydrochloride

To a solution of 14.0 g of H-Pbe-NH-NH-Z-hydrochloride in 120 ml of methanol at 20 ° C was first added 10.0 g of sodium cyanoborohydride and after 5 minutes 3.2 ml of piropionaldehyde. After a reaction time of 2.5 hours, the solvent is removed in vacuo, 50 ml of water are added to the residue, the mixture is made strongly alkaline (pH ca. 12j by addition of 10N sodium hydroxide) and the product is extracted with methylene chloride. Sodium was added and excess hydrogen chloride in ethyl ether was added and crystallization was then completed by the addition of additional ether to give the title compound, having an optical rotation of [α] _D ²⁰ = -T 42.5 ° C (c-1 in dimethylformamide).

b) Boc-Gly- (N-propyl) Phe-NH-NH-Z

To a solution of 16.8 g of Boc-Gly-OH in 100 mL of tetrahydrofuran at -20 ° C was added 11.8 mL of pivaloyl chloride, the mixture was stirred at -15 ° C for 15 minutes, then a solution of 12.5 was added. g of H- (N-propyl) Phe-NH-NH-Z and 5.5 ml of N-ethyl-diisopropylamine in 50 ml of tetrahydrofuran, the reaction mixture was stirred at -15 ° C for 1 hour, then at 0 ° for 1 hour. C and finally 20 hours at 10 ° C. After addition of 150 ml of 1N potassium hydrogen carbonate, the product is extracted with ethyl acetate, the extract is washed with dilute potassium hydrogen carbonate solution and potassium hydrogen sulphate and water, dried over sodium sulphate and the solvent is evaporated off under vacuum. The title compound is purified by chromatography using silica gel and methylene chloride / methanol as eluent.

c) Boc-Gly- (N-propyl) Phe-NH-NH 2

21.1 g of Boc-Gly- (N-propyl) -Phe-NH-NH-Z in 100 ml of methanol are hydrogenated in the presence of a palladium catalyst for 1 hour under a hydrogen pressure of 0.2 to 0.3 MPa. and the amorphous residue is dried over phosphorus pentoxide and potassium hydroxide in vacuo to give the title compound, having an optical rotation of [α] _D ²⁰ = -39.4 ° (c = 1 in dimethylformamide).

d) Boc-Gly- (N-propyl) Phe-Met-ol

To a solution of 7.8 g of Boc-Gly- (N-propyl) Phe-NH-NH2 in 50 ml of dimethylformamide at -18 ° C is added first with stirring

8.6 ml of 8 N hydrogen chloride in dloxane and then

2,1 ml teirc.butylnitrite. After standing for 10 minutes at -18 ° C, the mixture was neutralized by the addition of 12.0 ml of N-ethyl-diisopropylamine and treated with a pre-cooled solution of 5.4 g of methioninol [CH3SCH2CH2CH (NH3 / CH3OH) in 30 ml of dimethylformamide. The reaction mixture was diluted with ethyl acetate, washed with dilute potassium hydrogen carbonate solution and potassium hydrogen sulfate and water, dried over sodium sulfate, the solvent was evaporated in vacuo and the residue was purified by chromatography on silica gel using methylene chloride / methanol as eluent to give the title compound. the desired title compound.

e. H-Gly- (N-propyl) Phe-Met-ol hydrochloride

To a solution of 9.9 g of Boc-Gly- (N-propyl) Phe-Metol in 20 ml of ethyl ether was added at 0 ° C 100 ml of 5 N hydrogen chloride in ethyl ether. After an additional hour at 0 ° C, the solvent was evaporated in vacuo and the residue was recrystallized from a mixture of ethyl acetate, methanol and ethyl ether to give the title compound, having an optical rotation of [α] _D ²⁰ = -72.5 ° (c = 1 in dimethylformamide). The product decomposes at 60 ° C.

fj Boc-Tyr- (D) -Ala-NH-NH-Z

To a solution of 14.1 g of Boc-Tyr-OH and 5.6 ml of N-dimethylformamide in 100 ml of tetrahydrofuran was added 6.6 ml of isobutyl chloroformate at -20 ° C. After five minutes of reaction at -20 C, ^D, a solution of 13.7 g of H- (D j-Ala-NH-NH-Z-hydrochloride and 5.0 ml of N-methylmorpholine in 50 ml of dimethylformamide. The mixture was allowed to 2.5 The reaction mixture was diluted with ethyl acetate, washed with dilute potassium bicarbonate solution and potassium hydrogen sulphate and water, dried over sodium sulfate and the solvent was evaporated in vacuo. Recrystallization of the residue from a mixture of ethyl acetate, hexane and ethyl ether gave the title compound.

g) H-Tyr- (D 1 -Ala-NH-NH-Z-hydrochloride)

To a solution of 25.0 g of Boc-Tyr- (D) -Ala-NH-NH-Z in 50 ml of ethyl acetate at 0 ° C was added 100 ml of a 5 N solution of hydrogen chloride in ether. After 1.5 hours, crystallization was completed by addition of additional ethyl ether. The title compound is isolated by filtration. The product has an optical rotation of [α] _D ²⁰ = + 32.8 ° (c = 1 in dimethylformamide) and decomposes at 200 ° C.

h) N ^and -amidino-Tyr- (D) -Ala-NH-NH-Z-hydrochloride

To a solution of 8.8 g of H-Tyr- (D-Ala-NH-NH-Z-hydrochloride) and 2.8 ml of triethylamine in 50 ml of dimethylformamide was added 12.1 g of 1-amidino-3,5-dimethylpyrazolinitrate. After stirring for 4 days at 50-60 [deg.] C., 3.0 ml of triethylamine are added, the solvent is evaporated off under vacuum, the residue is taken up in water and the solution is extracted several times with methylene chloride. The adsorbent is adsorbed onto a polystyrene adsorption resin and the title compound is eluted from the adsorbent as a nitrate using a mixture of methanol and water as the eluent, the eluate is evaporated to dryness, the residue is dried again in vacuo, dissolved in ethyl acetate in the presence of a small amount of ethanol. and addition of ethyl ether and an excess of 5 N hydrogen chloride in ethyl acetate precipitates the title compound as the hydrochloride.

The product has an optical rotation of [α] _D ²⁰ - + 23.3 ° (c - 1 in dimethylformamide) and decomposes at 50 ° C.

N-ainidino-Tyr- (D-Ala-NH-NH2-hydrochloride)

1.6 g of N ^and -amidino-Tyr- (D) -Ala-NH-NH-Z-hydrochloride in 20 ml of methanol are hydrogenated under a hydrogen pressure of 0.2 to 0.3 MPa in the presence of a palladium catalyst. After 30 minutes, the catalyst is filtered off, the solvent is evaporated off under vacuum and the residue is recrystallized from a mixture of methanol and ethyl ether. The title compound is obtained, having an optical rotation of [α] _D ²⁰ = + 13.2 ° [α] 1-dimethylformamide, decomposing at 80 degrees Celsius.

jj N ^K -amidi, no-Tyr- (D) -Ala-Gly- (N-propyl) Phe-Met-ol hydrochloride

To a solution of 1.04 g ^and N-amidino-Tyr- (D Jala-NH-NH2 in 20 ml of the hydrochloride dimethylfarmamidu at -18 ° C was added first 1.3 ml 8 N HCl in dioxane and then 0.35 ml tert-butylnitrite.

After standing at -18 ° C for 10 minutes, the reaction mixture was neutralized

2.3 ml of N-ethyldiisopropylamine and mixed with a cooled solution of 1.5 g of H-Gly- (N-propyl) Phe-Met-ol-hydrochloride and 0.62 ml of N-ethyl-diisopropylamine in 15 ml of dimethylformamide. at -15 ° C followed by a three-hour reaction at -10 ° C, the solvent was evaporated in vacuo, the residue was taken up in water, and the solution was washed several times with methylene chloride. After evaporation of the eluate to dryness and precipitation from a mixture of methanol and ethyl ether, the title compound is obtained, having an optical rotation of [α] _D ²⁰ = -41.0 ° (c = 1 in dimethylformamide], decomposing at 90 [deg.] C. Example 2

The following compounds were prepared in an analogous manner to Example 1:

2.1. H-MeTyir- (D) -Ala-Gly- (N-propyl) Phe-Met (O) -ol-trifluoroacetate of optical rotation [.alpha.] D @ ²⁰ = -19.3 DEG (c = 1 in 95% acid) acetic),

2.2. H-MeTyr- (Dj-Ala-Gly- (N-isobutyl) Phe-Met {O-ol-trifluoroacetate with optical rotation [α] _D ²⁰ = -13.7 ° (c - 1 in 95% acetic acid,

2.3. H-MeTyr- (Dj-Ala-Gly- (N-butyl) Phe-Met (O) -ol-trifluoroacetate of optical rotation [α] D ²⁰ = -7.9 ° (c - 1 in 95%) acetic acid,

4.2 H MeTyr- {D) -Ala-Gly- (N-propyl] Phe (pF) -methyl {Oj-ol trifluoroacetate, optical rotation [a] _D ²⁰ - -9, ¹ O * (c - 1 95% acetic acid,

^And 2.5 N-amidino-Tyr- (D) -Ala-Gly-MePhe-Met (O) -ol acetate, optical rotation [a] D ²⁰ = -50.8 ° (c - 0.7 in of dimethylformamide) and

2.6. N '-amidino-Tyr- (D) -Ala-Gly-MeP.he (pF) -Met (O-ol-hydro-chloride with optical rotation [α] _D ²⁰ - 29.3 (c = 1 in 95) 1% acetic acid j.

Claims (2)

Subject A process for the preparation of pentaptides of the general formula I, A — B — Gly — D — E (I) in which A is a radical of formula (II) wherein Z ¹ represents a hydrogen atom, a methyl group or an amidinosuipine, R 1 represents a hydrogen atom or a C 1 -C 4 alkyl group; R2 is hydrogen or R 1 and R 2 together form an ethylene bridge and R3 represents a hydroxy or alkoxy group having 1 to 4 carbon atoms attached to the 3, 4 or 5 position, B represents the residue of the (D) -isomer of the natural α-amino acid, D is a radical of formula III, Z ² AND R4 CH2 I I -N-CH-CO- (III) in another m R 4 represents a hydrogen atom or a C 1 -C 4 alkyl group; Z ² represents a phenyl group optionally substituted by halogen or a nitro group, a nitro group, a (C 1 -C 4) alkyl group or a (C 1 -C 4) alkoxy group, and E is a radical of formula (IV), R5 R6 II -N-CH-CH ₂ OH (IV) wherein R 5 represents a hydrogen atom or a C 1 -C 4 alkyl group; R 6 represents a radical of formula - (CH) _n -CH ₂ -S (O) _p -R 7, wherein R2 represents an alkyl group having 1 to 5 carbon atoms, n is an integer of 0, 1 or 2 and p is an integer of 1 or 2, the radicals A and D having the (LJ-configuration), the radical E having the (Dj- or (Ly) -configuration and the residue B has the (DJ-configuration with the proviso that when Z ¹ is hydrogen or a methyl group, R4 represents an alkyl group with 3-4 carbon atoms, and the physiologically hydrolysable, physiologically acceptable esters and salts thereof and complexes of these pentapeptides and esters, characterized in that a pentapeptide or ester thereof is oxidized having the sequence shown in formula (I) wherein E is a radical of formula - (CH ₂ ) _n - CH 2 -S-Ry, where R 7 is as defined above, to give the corresponding pentaptide or ester in which E is a radical of the formula - (CH 2) _n --CH ₂ --S (O) p - R7, where η, p and R7 are as defined above, and the pentapeptide or ester thus formed is isolated in free form or in the form of an acid addition salt or complex. 2. A process according to claim 1, wherein the corresponding starting materials are used to form compounds of formula (I) in which: Z ¹ represents a hydrogen atom or a methyl group, R1 and R2 are either hydrogen or together are an ethylene bridge, R 3 is hydroxy at the 4-position, B is a residue of D-Ala, R 1 represents a C 3 -C 4 alkyl group, E represents a residue of Met (O) -ol a Z ² is as in point 1.