FR2577225A1 - Peptide derivatives which inhibit renin and acid proteases - Google Patents

Abstract

The invention relates to peptide derivatives whose model is based on that of pepstatin. These derivatives inhibit renin and acid proteases.

Description

Peptide Derivatives Inhibitors of Renin and Acid Proteases
The present invention relates to novel peptide derivatives that inhibit renin and acid proteases. It also relates to a process for obtaining them and their application in therapy.

In 1970, UMEZAWA isolated, from a streptomyces culture, a pentapeptide designated by the name of
Pepstatin whose structure has been established later and meets the formula
Isovaleryl-L-valyl-L-valyl-Statyl-L-alanyl-Statin in which is designated under the name "statin" an unusual amino acid, (3S, 4S) amino-4-hydroxy-3-hydroxy- 6 heptanoic.

 It has been shown that pepstatin is an inhibitor of acid proteases and acts in particular on pepsin, cathepsin D and renin. Specifically, renin, an enzyme of renal origin, mediates the angiotensinogen, angiotensin I, and angiotensin II sequences in the transformation of angiotensinogen into angiotensin.

 Angiotensin II, being a potent vasoconstrictor agent, interferes with the regulation of arterial pressure. It has been proposed to use pepstatin to combat high blood pressure in humans. However, since pepstatin acts on all acid proteases and has low solubility in aqueous media and a weak affinity for renin, its use in therapy has proved difficult.

Derivatives of pepstatin have been described in the scientific literature. For example, attempts have been made to reduce pepstatin by peptide chain elongation (J. Cardiovasc, Pharmacol., 1980, 2, 687-698).

 The present invention relates instead to peptides whose model is built on that of pepstatin.

In some cases, the introduction of non-natural amino acids makes it possible to increase the solubility of these compounds and their resistance to proteolysis. Surprisingly, it has been found that the peptides according to the invention, which carry hydrophilic residues at different sites, exhibit a high level of activity and much higher than that of pepstatin as inhibitor of human renin
The present invention relates to peptides having a high level of activity as inhibitors of renin and other acid proteases.

In the present description and in the claims, the following abbreviations will be used:
Amino acids and soups Protectors or activators.

 These abbreviations are in agreement with those indicated by the Nomenclature Commission of the IUPAC-IUB Biochemistry section. The most recent recommendations are reported in Eur. J. Biochem., 1984, 138, 5-7 and 9-37.

Amino acids :
Ala: Alanine
Asn: Asparagine
Asp: Aspartic acid
Gln: Glutamine
GLy: Glycine
His: Histidine Island: Isoleucine
Leu: Leucine
Met: Methionine
Nle: Norleucine
Nva: Norvaline
Phe: Phenylalanine
Ser: Serine
Sta: Statine
When the Statin is in the central position in the peptide, it always has the configuration (3S, 4S); When the Statin is in the terminal position, it may have One or
The other configuration (3S, 4S) -or (3R, 4S).

Derivatives of amino acids:
Met (02): Methionine dioxide (PhCH2) Asp: O-benzylaspartic acid
Abu: 2-Aminobutyric acid (Pyr-2) Ala: (Pyridyl-2) Aanine

(Pyr-3) Ala: (Pyridyl-3) Alanine
(Pyr-4) Ala: (Pyridyl-4) Alanine
These amino acids are, unless otherwise indicated, L configuration.

Protective groups and activators:
Ac: Acetyl
Boc: t-butyloxycarbonyl (Boc) 20: Bis-terbutyloxycarbonic anhydride
HONSu: N-hydroxysuccinimide
OEt: Ethyl ester
OMe: Methyl ester
ONp: - P-nitrophenyl ester
ONSu: Ester of N-hydroxysuccinimide oTcp: 2,4,5-Trichlorophenyl Ester iVa: Isovalery
Z: Benzoyloxycarbonyl
In addition, the following abbreviations will be used:
AcOEt: Ethyl acetate
AcOH: Acetic acid
Bop: benzyloxy tris dimethylamino hexafluorophosphate
phosphonium
TLC: Thin layer chromatography
DCCI: Dicyclohexylearbodiimide
DCHA: Dicyclohexylamine
DCU: Dicyclohexylated
DIPEA: Diisopropylethylamine
DMF: Dimethylformamide
DMSO: Dimethylsulfoxide
Ether: Ether
HOBt: Hydroxy-1 benzotriazole KHSO4-K2SO4: Aqueous solution Containing 16.6 g of bisulfate
of potassium and 33.3 g of potassium sulphate
for 1 liter
MeOH: Methanol
NEM: N-ethyl-morpholine
NMM: N-methyl-morpholine
TA: Room temperature
TFA: Trifluoroacetic acid
The compounds according to the invention correspond to the following general formula

où a = O, 1 ou 2

où n = O, 1, 2 ou 3

où D = -CH- ou -C
OH O où E = -H ou -CH3

où n = O, 1, 2 ou 3
NH2CH2CH2-SO2
BocNHCH2CH2-SO2
Z-NHCH2CH2-SO2
Alk-SO2
C6H5-(CH2)a-SO2-, où a = O, t ou 2, -Nk étant un groupement alkyle de C1 à C4, -R2 représente le groupement (CH2)b R5 dans lequel : . b = 0, 1, 2, 3 ou 4, et
.R5 est un atome d'hydrogène ou un radical phényte
ou naphtyle ou cyclohexyle ou pyridyle ; - R3 représente L'un des groupements suivants :
un alkyle (C2 à C6)
. un alcenyle (C2 à C6)
. un groupement A-R6 dans lequel : 1) A est soit -(CH2)d, où d = 1, 2, 3, 4
soit -CH-Alk
et R6 est l'un des restes suivants ::
-NH2, -N(ALk > 2, -NHW, où W = groupe protecteur tel que
benzyloxycarbonyle ;
o -COOH, -COO-Alk, -COOCH2C6H5 ;
-CONR7R8, où R7 et R8 sont différents ou identiques et représentent
H ou Alk ou C6H5 ; OH, -O-Alk, -OCH2C6H5, -OCH2-Pyr, où Pyr représente le radical 2-, 3- ou 4-pyridyle ; -S(O)eAlk, où e= O, 1, 2,
Alk étant un groupement alkyle de C1 a C4 ; 2) A est soit une liaison directe
soit (CH2)d, où d = 1, 2, 3, 4
soit -CH-Alk
R6 est l'un des restes suivants:
phenyle, naphtyle ou cycloalkyle comportant 3 à 6 atomes
de carbone
hétérocycle.monocyclique tel que: imidazole, oxazole, thiazole
ou tétrazole, thiophène, pyrrole, triazole, pyridine, cet hétérocycle
étant éventuellement substitué par Alk ou CF3,
Alk étant tel que défini ci-dessus ; - z1 représente l'isopropyle, le phényle ou le cyclohexyle formant respectivement avec le radical

le résidu de
l'aminoacide statine, a savoir, l'acide (3S,4S) amino-4
hydroxy-3 methyl-6 heptanolque ou de l'acide (3S,4S) amino-4
hydroxy-3 phenyl-5 pentanoique (AHPPA) ou de l'acide (3S,4S)
amino-4 cyclohexyl-5 hydroxy-3 pentanoique (ACHPA) ;- - X-Y est un dipeptide choisi parmi Ala-Sta, Ala-Leu, Leu-Phe,
Val-Sta, Abu-Sta, Phg-Sta ; - R4 représente l'un des groupements suivants: -OH, -OAlk',
-NH2, -NAlk'2, ON, où M est un métal et Alk' représente
un groupement alkyle de C1 à C6; - Z1 étant autre qu'isopropyle lorsque X-Y représente Ala-Sta.<tb><SEP> H
<tb><SEP> R1 <SEP> -NH-CH-C-NH-CH-CN-CH-CHOH-CH2-CXY-R4 <SEP> (I)
<tb><SEP> R2 <SEP> O <SEP> R3 <SEP> 3 <SEP> CH2 <SEP> O
<tb> in <SEP> which <SEP>:
<tb> - R1 represents one of the following groupings:

where a = O, 1 or 2

where n = 0, 1, 2 or 3

where D = -CH- or -C
OH where E = -H or -CH3

where n = 0, 1, 2 or 3
NH2CH2CH2-SO2
BocNHCH2CH2-SO2
Z-SO2-NHCH2CH2
Alk-SO2
C6H5- (CH2) a-SO2-, where a = O, t or 2, -Nk being an alkyl group of C1 to C4, -R2 represents the group (CH2) b R5 in which: b = 0, 1, 2, 3 or 4, and
.R5 is a hydrogen atom or a phenyl radical
or naphthyl or cyclohexyl or pyridyl; - R3 represents one of the following groupings:
an alkyl (C2 to C6)
. alkenyl (C2 to C6)
. an A-R6 group in which: 1) A is either - (CH2) d, where d = 1, 2, 3, 4
be -CH-Alk
and R6 is one of the following remains:
-NH2, -N (ALk> 2, -NHW, where W = protecting group as
benzyloxycarbonyl;
o -COOH, -COO-Alk, -COOCH2C6H5;
-CONR7R8, where R7 and R8 are different or the same and represent
H or Alk or C6H5; OH, -O-Alk, -OCH2C6H5, -OCH2-Pyr, where Pyr is 2-, 3- or 4-pyridyl; -S (O) eAlk, where e = O, 1, 2,
Alk is an alkyl group of C1 to C4; 2) A is either a direct link
either (CH2) d, where d = 1, 2, 3, 4
be -CH-Alk
R6 is one of the following remains:
phenyl, naphthyl or cycloalkyl having 3 to 6 atoms
of carbon
Monocyclic heterocycle such as: imidazole, oxazole, thiazole
or tetrazole, thiophene, pyrrole, triazole, pyridine, this heterocycle
being optionally substituted with Alk or CF3,
Alk being as defined above; z1 represents isopropyl, phenyl or cyclohexyl respectively forming with the radical

the residue of
the amino acid statin, namely, (3S, 4S) amino-4
3-hydroxy-6-methylheptanol or 3S, 4S-4-amino acid
3-hydroxy-5-phenylpentanoic acid (AHPPA) or (3S, 4S) acid
4-amino-5-cyclohexyl-3-hydroxy pentanoic acid (ACHPA); XY is a dipeptide selected from Ala-Sta, Ala-Leu, Leu-Phe,
Val-Sta, Abu-Sta, Phg-Sta; - R4 represents one of the following groups: -OH, -OAlk ',
-NH2, -NAlk'2, ON, where M is a metal and Alk 'represents
an alkyl group of C1 to C6; Z1 being other than isopropyl when XY represents Ala-Sta.

 The present invention also includes the salts of inorganic or organic acids of the pharmaceutically acceptable peptides of formula (I).

The products according to the invention can be prepared according to the usual methods of peptide chemistry. More particularly, from a compound of formula
HY-OAlk in which Alk represents a C1 to C4 alkyl and Y is chosen from the residues of the amino acids Sta, Leu and Phe, are coupled, step by step, the various suitably protected amino acids, the product obtained at each stage being deprotected, according to known methods, before being subjected to a new coupling, each of the coupling operations being carried out using either an activated ester of the amino acid to be coupled, or the amino acid
N-protected in the presence of dicyclohexylcarbodiimide. The starting material is a lower alkyl ester of the C-terminal amino acid on which the next amino acid in the sequence is condensed.

avec lsaminoneide suivant.After releasing the amine function of the dipeptide, the peptide chain is elongated by coupling of the next amino acid, suitably protected. Each coupling phase is followed by a selective operation of release of the amine which will be reacted during the creation of the next peptide bond. The various coupling operations are carried out either by using an activated ester of the amino acid to be coupled, or using the N-protected amino acid in the presence of dicyclohexylcarbodiimide. The phases of selective deprotection of the amine are carried out according to nature. of the protecting group used either by hydrogenolysis or by acidotysis in a strong acid medium, such as trifluoroacetic acid. When the amino acid to be introduced into the sequence has a reactive function in its side chain, it should be blocked by a suitable protecting group which is subsequently removed.
The protection of the initial amino acid by the group R 1 s 1 is carried out according to known methods, before the coupling of the residue

with the next aminoneide.

 When the compound (I) bears a substituent R3 such that the corresponding residue is a non-natural amino acid, it is prepared according to known methods. It is then coupled with the next amino acid according to the usual method.

 Peptides (I) in acid form (R4 = OH) can be obtained from the corresponding esters by saponification in a dilute alkaline medium. Their salts can also be prepared (R4 = OM). The peptides (I) in amide form (R4 = NH2 or R4 = NCAlk) 2) are obtained directly-taking as starting material the amino acids in amide form which exist commercially.

 According to the general scheme, it is possible either to prepare the entire desired sequence, or to prepare two fragments of this sequence that are ultimately coupled to obtain the desired peptide.

 The compounds of the present invention have an inhibitory action on human plasma renin activity very important and generally much higher than that of the natural product: pepstatin; as such they can be used in the treatment of high blood pressure.

 They also have a marked inhibitory action on acid proteases, including pepsin. It is therefore possible to envisage the use of the products according to the invention in therapeutic areas where the inhibition of such enzymatic systems is justified, in particular, in addition to arterial hypertension, peptic ulcer and inflammatory diseases.

 The present invention also relates to antihypertensive drugs containing the peptides of formula (I) or their pharmaceutically acceptable salts as active principle.

 The peptides of the present invention can be used therapeutically by injection: intravenously, intramuscularly or subcutaneously. They are used in a solvent such as saline (isotonic saline) or in a buffer, such as phosphate buffer; they may also be suspended in a pharmaceutically acceptable aqueous or non-aqueous diluent, Each dosage unit may contain from 1 to 1000 mg of active ingredient.

The amount of active ingredient to be used varies according to the desired therapeutic effects, the severity of the
The condition to be treated and the chosen route of administration. It must be determined for each patient and is most often between 0.100 g and 2 g of active ingredient.

 The following nonlimiting examples are given by way of illustration of the present invention.

 In all of these examples, the pH of the solutions in an organic solvent is measured or monitored using wet pH indicator paper.

 The melting points indicated (Fc) are taken from triturated solids; they are measured in the capillary tube.

 Finally, the nuclear magnetic resonance spectra were recorded at 250 MHz, in solution in DMSO, the internal standard being hexamethyldisiloxane.

 The following abbreviations are used: singlet d: doublet m: multiplet or massive.

 The chemical shifts (delta) are measured in ppm.

EXAMPLE 1
Boc-Phe- (PhCH2) Aso-Sta-Ala-Leu-OMe (SR 42926)
1. Boc-Ala-Leu-OMe
In 50 ml of CH 2 Cl 2, 2.86 g of Boc-ALa-ONSu, 1.81 g of Leu-OMe, HCl and 1.15 g of NEM are successively dissolved at RT. It is checked that the pH is 6-7, otherwise it is adjusted by adding NEM. The mixture is stirred for 4 hours at RT and then the organic solution is washed successively with 5% KHSO 4 -K 2 SO 4, water and 5% NaHCO 3; It is dried over Na 2 SO 4 and the solvent is evaporated to give an oil.

Yield: 2.93 g (92%).

2. Ala-Leu-OMe, TFA
360 mg of the previous product are covered with 5 ml of TFA. After 20 min, the TFA is evaporated, the residue is taken up in a mixture, equal volume, pentane-ether. By scraping a white solid appears, it is drained, rinsed with ether, dried.

Yield: 320 mg (85%).

3. Boc-Sta-Ala-Leu-OCH3
330 mg of the previously obtained TFA salt are solubilized in 30 ml of dioxane containing 230 mg of NEN, 275 mg of Boc-Sta-OH, 206 mg of DCCI and 135 mg of HOBt are added, the pH is adjusted to a value of 6-7 by NEM if necessary, then stir 24 hours at RT. The DCU is filtered, the solvent is evaporated, the residue is dissolved in a mixture of equal volume, AcOEt-hexane and chromatography on a column of Merck silica gel 60 in the same solvent mixture, eluting with 250 ml of the same solvent mixture. then 250 ml of the mixture in the proportion 75/25 by volume, then 100 ml of AcOEt. The fractions containing the product are evaporated, taken up in ether, drained and dried.

Yield: 380 mg (80 X).

4. Boc- (PhCH2) Asp-Sta-Ala-Leu-OMe
473 mg of the previously obtained peptide are treated at 0 ° C. for 15 minutes with 8 ml of TFA; concentrated in vacuo at t = 250C, taken up in ether and evaporated. A solid is obtained which is taken up in CH 2 Cl 2, the salt is neutralized with a slight excess of NMM, then 405 mg of Boc- (PhCH 2 Asp), 191 mg of HOBt and 258 mg of DCCI are added. The pH is adjusted to 7 by addition of NMM and stirred for 18 h. It is then washed with a solution of
KHSO4 (about 1M), with a solution of NaHCO3 (about 1M), dried and concentrated. After chromatography on a silica column with AcOEt as eluent, 169 mg of the expected product is obtained, which crystallizes on evaporation; Fc = 147-149C.

5. SR 42926
169 mg of the above product are treated with 8 ml of TFA at 0 ° C. for 15 minutes. It is concentrated under vacuum at 25 ° C., taken up in ether and evaporated. An oil is obtained which is taken up in CH 2 Cl 2 and the salt is neutralized in the cold by a slight excess of NMM.

A mixture of 100 mg of Boc-Phe-ONp, 38 mg of HOBt, 26 mg of NMM is stirred for 2 h in CH 2 Cl 2 - and then added to the above salt. After stirring for 24 h, the organic phase is washed with a solution of KHSO 4, NaHCO 3, dried and concentrated. After chromatography on silica (eluent AcOEt), the expected product which crystallizes on evaporation of the solvent is obtained.

Yield: 103 mg (50%); Fc = 154-155C.

NMR spectrum

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 8.34 <SEP> - <SEP> 7.05 <SEP> m <SEP> 14 <SEP> H <SEP> 4 <SEP> NHCO
<tb><SEP> 10 <SEP> H <SEP> Aromatic
<tb><SEP> 6.86 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NHCO2
<tb><SEP> 5.04 <SEP> s <SEP> 2 <SEP> H <SEP> CO2CH2C6H5
<tb><SEP> 3.55 <SEP> s <SEP> 3 <SEP> N <SEP> 0CM3 <SEP>
<tb> 2.20 <SEP> - <SEP> 2.00 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb><SEP> 1.20 <SEP> s <SEP> 9 <SEP> H <SEP> C (CH3) 3 <SEP>
<tb><SEP> 1.13 <SEP> d, <SEP> J = 7 <SEP> Hz <SEP> 3 <SEP> H <SEP> CH3 <SEP> (Ala)
<tb> 0.86 <SEP> - <SEP> 0.69 <SEP> m <SEP> 12 <SEP> H <SEP> (CH3) 2CH
<tb> Example 2
Boc-Phe-Asp-Sta-Ala-Leu-OMe (SR 42927)
90 mg of SR 42926 prepared according to Example 1 are.

dissolved in 30 ml of AcOEt then hydrogenolysis is carried out under the pressure of a column of water and in the presence of 90 mg of palladium on carbon (Pd at 10%). After 3 hours of reaction, it is filtered through Celite, washed with AcOEt then concentrated. The solid obtained is triturated in a hexane-ether mixture, filtered and dried under vacuum.

Yield: 63 mg (78.7%) t Fc = 163-165 ° C.

NMR spectrum
The NMR spectrum is analyzed by comparison with that of SR 42926. The loss of aromatic 5H between 7.8 and 7 ppm and the loss of benzyl CH 2 at 5.04 ppm are noted.

Example 3
Boc-Phe- (2-methylthiazolyl-4) Gly-Sta-Ala-Leu-OMe (SR 43059)
1. (R, S) (2-methyl-4-thiazolyl) ethyl glycinate
This product is prepared according to the method described in J. Med. Chem, 1973, 16, 978-984.

2. (RS) (2-Methylthiazolyl-4) N-tert-butylcarbonyl
methyl glycinate
6.5 g of the compound prepared above are stirred for 3 days in 60 ml of water with 8.1 g of Boc 2 O, 32.5 ml of dioxane and triethylamine to obtain an alkaline pH. It is then concentrated to 30 ° C., taken up in ether, washed with water and then with a solution of KHSO 4, with water, a solution of NaHCO 3, dried and concentrated. 8.5 g of a yellow oil are obtained.

3. (R, S) (2-Methylthiazolyl-4) N-tert-butylcarbonyl
wistaria
4.5 g of the previously obtained compound are reacted in 80 ml of dioxane with 0.72 mg of sodium hydroxide dissolved in 15 ml of water. The reaction is monitored by TLC. After 2 hours, 0.6 g of sodium hydroxide in 2 ml of water are added. After 3:45 min, there is no starting material. It is brought to pH 5 with 15 ml of 1 N HCl, concentrated at 30 ° C., taken up in water, acidified with KHSO4, extracted with AcOEt, washed with water, dried and concentrated. 2.7 g of yellow powder are collected.

4. Boc-Sta-Ala-Leu-OMe
This peptide is prepared according to the method described in Example 1.

5. (R, S) Boc- (2-Methylthiazolyl-4) Gly-Sta-Ala-Leu-OMe
473 mg of the preceding product are placed in 5 ml of TFA at 0 ° C. After 20 min, the mixture is concentrated, taken up again three times with anhydrous ether and then concentrated to the maximum. The product obtained is dissolved in 20 μl of CH 2 Cl 2 and brought to pH 7 by the addition of DIPEA. 260 mg of the compound obtained in step 3 and 441 mg of Bop are then added. After stirring for 4 days at pH 7, it is treated with salt water and then with bicarbonate water and with water, dried and concentrated, and then chromatography on silica. By elution with AcOEt etching a 9/1 by volume AcOEt-MeOH mixture, an amorphous solid fraction of 607 mg is collected by precipitation in pentane.

6. SR 43059
251 mg of the compound obtained above are placed in 4 ml of TFA at 0 ° C. and then undergo the usual treatment.

The TFA salt obtained is placed in 15 ml of CH 2 Cl 2, the reaction medium is brought to pH 7 by addition of DIPEA and then 149 mg of Boc-Phe-ONp and 61.2 mg of HOBt are added. After 24 hours, the mixture is washed in the same manner as in the previous step and then chromatographed on silica eluting with a 9/1 by volume AcOEt-AcOH mixture. 230 mg of white powder is collected.

NMR Soectre

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Assignment
<tb> 7 <SEP> - <SEP> 8.4 <SEP> m <SEP> 11 <SEP> H <SEP> 5 <SEP> NH
<tb><SEP> 5 <SEP> H <SEP> Aromatic <SEP> (Phe) <SEP>
<tb><SEP> 1 <SEP> H <SEP> thiazoLic
<tb><SEP> 3.5 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<tb><SEP> 1.25 <SEP> s <SEP> 9 <SEP> H <SEP> C (CH3) 3
<tb> Exemole 4 Boc-Phe- (evr-3) Ala-Sta-Leu-Phe-OMe (SR 43064 and SR 43066)
1. (R, S) 2-Acetamido ethoxycarbonyl-2 (3-pyridyl) -3
ethyl propionate
To 11 g of a solution of sodium-in 300 ml of
EtOH is added 48 g of diethyl acetamidomalonate and then, under refluxing, 36 g of chloromethyl-3-pyridine hydrochloride are added, the mixture is kept at reflux for 5 hours. EtOH is evaporated, taken up in water, extracted, dried, concentrated and chromatographed on silica. The mixture CH2Cl2-AcOEt 60/40 by volume elutes 23 g of the expected compound.

2. (R, S) (Pyr-3) Ala, 2HCl
15 g of the preceding diester are refluxed in 200 ml of 5 N HCl for 5 h. Concentrate to dryness, add EtOH, evaporate. The process is repeated until recrystallization of the dihydrochloride: 15 g.

3. (R, S) Boc (Pyr-3) Ala
1 g of the above dihydrochloride is. dissolved in a mixture of equal volume water-dioxane. 350 mg of sodium hydroxide and 1 g of (Boc) 20 are added, followed by stirring overnight at RT. The dioxane is evaporated, water is added, neutralized with 8 g of amberlite CG 120 t
(acid form), stirred for 1 hour at RT and then the medium is placed on a column containing 8 g of the same resin. Eluted with distilled water until pH 5 is obtained and then eluted with a 4% ammonia solution. in distilled water. The waters are concentrated. 0.69 g of the expected product is collected.

4. Boc- (Pvr-3) ALa-Sta-OMe
A mixture of 465 mg of Sta-OMe, TFA and 500 mg of Boc- (Pyr-3) is stirred for 3 days at RT in 10 ml of acetonitrile.
Ala in the presence of 780 mg of Bop, the medium being maintained at pH 7 by addition of DIPEA. It is then evaporated to dryness, water is added, the mixture is extracted with AcOEt, the solution is washed with Na2CO3 solution, with water and with saline water and dried over MgSO4 and evaporated to dryness.

The residue is chromatographed on silica gel using a CH2Cl2-AcOEt eluent mixture at 1/9 by volume, which successively elutes:
the less polar isomer A: 150 mg;
the more polar isomer B te: 180 mg.

5. Leu-Phe-OMe
This dipeptide is prepared according to the coupling method described in the preceding examples.

6. Boc- (Pyr-3 (Ala-Sta-Leu-Phe-OMe
This compound is first prepared from mother isolate A isolated in step 2. 200 mg of this isomer A are hydrolyzed at RT for 1 hour in a mixture of equal volume water-dioxane. It is partially evaporated under reduced pressure at RT, a trace of HCl is added to bring the pH to 4, then evaporated to dryness and dried under vacuum. The residue is taken up in 10 ml of acetonitrite, 200 mg of Leu-Phe-OCH3, TFA, 230 mg of Bop are added and the reaction medium is maintained for 18 hours at pH 7 by the addition of DIPEA.

Then evaporated to dryness, added bicarbonate water, extracted with AcOEt. The organic phase, washed with water, with saline water and then dried over MgSO 4, gives the crude peptide after evaporation.

It is purified by chromatography on silica gel using CH.sub.2 Cl.sub.2 -AcOEt as a 1: 4 by volume eluent. 300 ag product is obtained.

7. SR 43066
197 mg of the above compound are contacted at 00 ° C. for 20 minutes with 5 ml of TFA, the solvent is then evaporated, and the resulting mixture is dried under vacuum. The residue is suspended in CH 2 Cl 2 and neutralized with DIPEA. 110 mg of Boc-Phe-ONp and 45 mg of HOBt are added in solution in CH2Cl2; the mixture is then stirred for 18 h at RT keeping the pH at 7 by addition of DIPEA. Evaporated to dryness, added carbonated water and extracted with AcOEt, after washing with water and drying over MgSO4, the residue is chromatographed on silica gel (eluent AcOEt). 150 mg of SR 43066 is obtained.

8. SR 43064
From the isomer B isolated in step 2, steps 4 and 5 are performed to prepare SR 43064.

NMR spectrum
SR 43066

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 6.80 <SEP> d, <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NH <SEP> - <SEP> Boc
<tb><SEP> 4.84 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SE> OH <SEP> (Sta)
<tb> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3
<tb><SEP> 2,16-2,05 <SEP> m <SEP> 2 <SEP> H <SEP> CH2-CO <SEP> (Sta)
<tb><SEP> 1.20 <SEP> s <SEP> 9 <SEP> H <SEP> (CH3) 3C
<Tb>
SR 43064

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 6.85 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NH <SEP><SEP> - <SEP> Boc
<tb><SEP> 4.83 <SEP> I <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta) <SEP>
<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> QCfi <SEP>
<tb><SEP> 2.10-1.95 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb> 1.21 <SEP> s <SEP> 9 <SEP> H <SEP> (CH3) 3C
<Tb>
Example 5
Boc-Phe- (Pyr-4) Ala-Sta-Leu-Phe-OMe (SR 43065 and SR 43144)
1. Boc- (Pyr-4) Ala-Sta-OMe
Working as in the preceding example, Boc- (Pyr-4) Ala is first prepared, then this product is coupled with Sta-Or-TFA. Isomer is isolated successively 2 isomers by chromatography.
- less polar isomer A;
- B isomer

2. SR 43065
This compound is obtained from the isomer A by operating as in the previous example.

3. SR 43144
This compound is obtained from isomer B by operating as in the previous example.

NMR spectrum SR 43065

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 6.82 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NH <SEP> - <SEP> Boc
<tb><SEP> 4.85 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta)
<tb> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3
<tb><SEP> 2,10-2,07 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb><SEP> 1.21 <SEP> s <SEP> 9 <SEP> H <SEP> (CH3) 3C
<Tb>
SR 43144

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 6.87 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NH <SEP> - <SEP> Boc
<tb><SEP> 4.85 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta)
<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> 0CH3 <SEP>
<tb> 2.10-2.00 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb><SEP> 1.23 <SEP> s <SEP> 9 <SEP> H <SEP> (CH3) 3C
<Tb>
Example 6
Boc-Phe- (Pyr-2) Ala-Sta-Leu-Phe-OMe CSR 43150 and SR 43151)
1. (R, S) Boc-Phe- (Pyr-2) Ala
The mixture is stirred for 48 hours at RT in 30 ml of the mixture
1/2 volume DMF-dioxane 1 g of 2-pyridylalanine dihydrochloride, 1.65 g of Boc-Phe-ONp in the presence of 2.5 ml of triethylanine. An insoluble light is filtered off, the solution is evaporated to dryness and the residue is chromatographed on silica gel.
CHCl 3 -MeOH, NH 4 OH (84/15/5 by volume) elutes the dipeptide in the form of a water-soluble foam.

Yield: 58%.

2. Boc-Phe- (Pyr-2) Ala-Sta-OMe
To 808 mg of the above product at 0 ° C. in CH 2 Cl 2, 880 mg of BOp and DIPEA are added; then, after 15 min of contact, 600 mg Sta-OMe, TFA and bring the pH to 6-7 by addition of DIPEA. The mixture is stirred for 4 days at RT and then evaporated to dryness, carbonated water is added and AcOEt is extracted. After washing with water and saline water, an oil is isolated. 850 mg are chromatographed on silica gel, eluting with AcOEt, successively isolating: the least polar tripeptide A, homogeneous TLC; the most polar tripeptide B containing 30% of A.

3. SR 43150
This compound is obtained from the isomer A by following the method described in Example 9.

4. SR 43151
This compound is obtained from the isomer ss and contains, after purification, 30 to 40% of SR 43150.

NMR spectrum
SR 43150

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 6.86 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NH <SEP> - <SEP> Boc
<tb><SEP> 4.76 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SE> OH <SEP> (Sta)
<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> li <SEP><SEP> OCH3 <SEP>
<tb> 2,13-2,07 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta) <SEP>
<tb><SEP> 1.22 <SEP> s <SEP> 9 <SEP> H <SEP> (CH3) 3C <SEP>
<Tb>
SR 43151 (containing 30 to 40% of SR 43150)

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 6.93-6.85 <SEP> d, <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NH <SEP> - <SEP> Boc
<tb> 4.75-4.82 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta)
<Tb>

<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> OCli3 <SEP>
<tb> 2.14-1.95 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb><SEP> 1.23 <SEP> s <SEP> 9 <SEP> H <SEP> (CH3) 3C
<Tb>
EXAMPLE 7
N - ((2-pyridyl) -4-oxo-butyryl) -Phe-Nl-Sta-Leu-Phe-OMe (SR 42793)
1. N - ((2-pyridyl) -4-oxo-butyryl)
In 10 ml of acetonitrile, 1 g of
Phe-OMe, HCl, 830 mg of (2-pyridyl) 4-oxo-butyric acid in the presence of 2.05 g of Bop and 940 mg of NEM. After 3 days, evaporate to dryness, add water and AcOEt, wash several times with carbonated water, water, saline water, dry and evaporate. Isolate 1.25 g of solid which is purified by chromatography on silica gel, eluting with a mixture of equal volume of pentane and AcOEt. After recrystallization from CH2Cl2-Et2O, 870 mg of the expected product is obtained.

2. N - ((Pyridyl-2) -4-oxo-butyryl) -Phe-OH
810 mg of the above ester in 15 ml of methanol are hydrolysed for 4 hours at RT with 190 mg of sodium hydroxide in 5 ml of water. It is evaporated to dryness, added carbonated water, extracted with AcOEt and then acidified to pH 4.65 while checking with the pH meter.

Then extracted with AcOEt, washed with water, saline water and evaporated.

The white solid obtained is recrystallized from MeOH-Et2O;
Fc = 115-1200C.

3. SR 42793
The procedure is then carried out according to the methods described above to obtain the expected product.

NMR spectrum

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 8.67-7.05 <SEP> m <SEP> 19-H <SEP> 5 <SEP> NHCO
<tb><SEP> 10 <SEP> H <SEP> Aromatic
<tb><SEP> C6H5
<tb><SEP> - <SEP> 4 <SEP> H-aromatic <SEP>
<tb><SEP> C5H4N
<Tb>

<tb><SEP> 4.78 <SEP> d, <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SE> OH <SEP> (Sta)
<tb><SEP> 4.50-4.11 <SEP> m <SEP> 4 <SEP> H <SEP> CH <SEP> (alpha)
<tb><SEP> 3.81-3.67 <SEP> m <SEP> 2 <SEP> H <SEP> CHOH <SEP> (Sta)
<tb><SEP> CHNH <SEP> (Sta)
<tb><SEP> 3.48 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<tb><SEP> 2.13-2.00 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb><SEP> 1.71-1.05 <SEP> i <SEP> | <SEP> 12 <SEP> H <SEP> CH, <SEP> CH2 <SEP> atiphatic
<tb> 0.89-0.68 <SEP> m <SEP> 15 <SEP> H <SEP> CH3 <SEP> (Nle)
<tb><SEP> (CH3) 2CH <SEP> (Leu)
<tb><SEP> (CH3) 2CH <SEP> (Sta)
<Tb>
Example 8 (R, S) N- (Pyridyl-2) -4-hydroxy-4-butyryl) -Nhe-Sta-Leu-Phe-OMe (SR 42991)
This compound is obtained by reducing the
SR 42793. 23 mg of SR 43793 are dissolved in 2 ml of MeOH and 10 mg of BH4Na is added at RT. After 18 h, an excess KHSO4 solution is added, the mixture is stirred for 10 min and then carbonated water is added and the mixture is evaporated to coldness. It is extracted with 3 volumes of AcOEt, washed with water and dried over K2SO4. On evaporation, a solid is isolated which is triturated in the ether-hexane mixture.

16 mg of the expected product are obtained.

NMR spectrum

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 8.43-7.0 <SEP> m <SEP> 19 <SEP> H <SEP> 5 <SEP> NHCO
<tb><SEP> 10 <SEP> H <SEP> Aromatic
<tb><SEP> C6H5
aromatic <tb><SEP> 4 <SEP> H <SEP>
<tb><SEP> C5H4N
<tb><SEP> 5.34 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH
<tb><SEP> 4.80 <SEP> d, <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SE> OH <SEP> (Sta)
<tb> 4.70-4.00 <SEP> m <SEP> 5 <SEP> H <SEP> CH <SEP> (alpha)
<tb> 3.80-3.66 <SEP> m <SEP> 2 <SEP> H <SEP> CHOH <SEP> (Sta)
<tb><SEP> 3.48 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3
<tb> 2,13-0,63 <SEP> m <SEP> 33 <SEP> H
<Tb>
Using the same coupling methods, the following compounds were prepared:

<tb> N "<SEP> SR <SEP> i <SEP> Formula
<tb> 42757 <SEP> Boc-Phe-NLe-Sta-Abu-Sta-OMe
<tb> 42759 <SEP> 1 <SEP> BOc-Phe-Nle-Sta-Abu-Sta-OH
<tb> 42871 <SEP> 1 <SEP> I <SEP> tBenzoyl) -Phe-Nle-Sta-Ala-Leu-OMe
<tb> 42872 <SEP> I <SEP> (Cyclohexyl <SEP> carbonyl) -Phe-Nle-Sta-Ala-Leu-OMe
<tb> 42873 <SEP> (Nicotinoyl) -Phe-Nle-Sta-Ala-Leu-OMe
<tb> 43108 <SEP> N- (<SEP> (py <SEP> ri <SEP> dy <SEP> 1-3) <SEP> -4 <SEP> oxo-4 <SEP> butyry <SEP> L) -Phe-N <SEP> The-Staeu-Phe-OIe
<tb> 43123 <SEP> (R, S) <SEP> N - ((3-Pyridyl) -4 <SEP> 4-hydroxy-4 (SEP) butyryl) -Phe-Nle-Sta
<tb><SEP> Leu-Phe-OMe
<tb> 43282 <SEP> N - '(pyridyl-3) (SEP) acetyl) -Phe-Nle-Sta-Leu-Phe-OMe
<tb> 43314 <SEP> N - ((pyridyl-2) <SEP> acetyl) -Phe-Nle-Sta-Leu-Phe-OMe
<tb> 43366 <SEP> Boc-Phg-Phg-Sta-Leu-Phe-OMe <SEP>
<tb> 43428 <SEP> Boc-Phe- (<SEP> Cmethyl-1 <SEP> imidazolyl) -2) Ala-AHPPA-Ala-Sta-OCH3
<tb> 95508 <SEP> Boc-Phe-NH-CH-CO-Sta-Leu-Phe-NH2
<tb><SEP> CH2-NHZ
<tb> 95509 <SEP> Boc-Phe-NH-CH-CO-Sta-Leu-Fhe-NH2
<tb><SEP> (C1H2) 3-NHZ
<tb> PZ <SEP> V <SEP> 867 <SEP> Nt (pyridyl-3) -3 <SEP> propionyl) -Phe-Nle-Sta-Leu-Phe-OMe
<tb> PZ <SEP> V <SEP> 875 <SEP> N - ((pyridyl-2) -4 <SEP> butyryl) -Phe-Nle-Sta-Leu-Phe-Otïe
<Tb>
These products are characterized by their NMR spectrum.

SR 42757

<tb> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 7.41 <SEP> to <SEP> 7.90 <SEP> 4 <SEP> d <SEP> 4 <SEP> H <SEP> 4 <SEP> NHCO
<tb><SEP> 7,10-7,35 <SEP> m <SEP> 5 <SEP> H <SEP> H <SEP> Aromatic
<tb><SEP> 6.95 <SEP> d <SEP> 1 <SEP> H <SEP> NH <SEP> (Boc) <SEP>
<tb><SEP> 4.96 <SEP> d <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta)
<tb><SEP> 4.82 <SEP> d <SEP> 1 <SEP> H <SE> OH <SEP> (Sta)
<tb><SEP> 3.65-4.28 <SEP> m <SEP> 7 <SEP> H <SEP> 3 <SEP> H <SEP> alpha
<tb><SEP>;;<SEP> 2 <SEP> CH-CH <SEP>(Sta><SEP>
<Tb>

<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> CH3 <SEP> ester
<tb><SEP> 2.53-2.95 <SEP> m <SEP> 2 <SEP> H <SEP> CH2 <SEP> (Phe)
<tb><SEP> 2.00-2.40 <SEP> m <SEP> 4 <SEP> H <SEP> 2 <SEP> CH2 <SEP> (Sta) <SEP>
<tb><SEP> CH2 <SEP> (Abu)
<tb><SEP> 1.00-1.72 <SEP> m <SEP> 23 <SEP> H <SEP> (CH2) 3 <SEP> (Nle)
<tb><SEP> C (CH3) 2 <SEP> (Boc)
<tb> 2 <SEP> 2 <SEP> CH2-CH <SEP><Sta)
<tb><SEP> 0.61-0.95 <SEP> m <SEP> 18 <SEP> H <SEP> CH3 <SEP> (Abu)
<tb><SEP> CH3 <SEP> (Nle)
<tb><SEP> 2 <SEP> C (CH3) <SEP> (Sta)
<Tb>
SR 42759
Similar to that of 42757 with disappearance of the signal corresponding to the methyl ester at 3.50 ppm.

SR 42871

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 7.1 <SEP> to <SEP> 8.7 <SEP> m <SEP> complex <SEP> 15 <SEP> H <SE> R <SEP> NH <SEP>
<tb><SEP> 10 <SEP> H <SEP> Aromatic
<tb><SEP> 4.8 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> I <SEP> H <SEP> OH <SEP> (Sta) <SEP>
<tb><SEP> 3.5 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<Tb>
SR 42872

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 7 <SEP> to <SEP> 8.2 <SEP> m <SEP> complex <SEP> 10 <SEP> H <SEP> 5 <SEP> H <SEP> C6H5
<tb><SEP> 4.8 <SEP> d, <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> 5 <SEP> NH, <SE> OH <SEP> (Sta )
<tb><SEP> 4.1-4.45 <SEP> m <SEP> complex <SEP> 4 <SEP> H <SEP> 3 <SEP> H <SEP> alpha
<tb><SEP> 1 <SEP> H <SEP> isopropyl <SEP> (Leu)
<tb><SEP> 3.75 <SEP> m <SEP> 2 <SEP> H <SEP> 1 <SEP> H <SEP> alpha <SEP> (Sta)
<tb><SEP> 1 <SEP> H <SEP> isopropyl <SEP> (Sta)
<tb> 3.5 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3
<Tb>
SR 42873

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 7 <SEP> and <SEP> 8.9 <SEP> m <SEP> complex <SEP> 14 <SEP> H <SEP> 5 <SEP> NH
<tb><SEP> 4 <SEP> H <SEP> C5H4N
<tb><SEP> 5 <SEP> H <SEP> C6H5
<tb><SEP> 4.8 <SEP> d, <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> 1 <SEP> H, <SE> OH <SEP> (Sta )
<tb><SEP> 4.25 <SEP> m <SEP> 3 <SEP> H <SEP> H <SEP> alpha
<tb><SEP> (Phe, <SEP> Nle, <SEP> Leu)
<tb><SEP> 3.8 <SEP> s <SEP> wide <SEP> 2 <SEP> H <SEP> 2 <SEP> H <SEP> alpha
<tb><SEP> (Sta, <SEP> Ala)
<tb><SEP> 3.55 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<Tb>
SR 43108

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 9.02-7 <SEP> m <SEP> 19 <SEP> H <SEP> 10 <SEP> H <SEP> C6H5 <SEP>
<tb><SEP> 4 <SEP> H <SEP> C5H4N
<tb><SEP> 5 <SEP> NH <SEP> CO
<tb><SEP> 4.80 <SEP>. <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta)
<tb> 4.52-4.09 <SEP> m <SEP> 4 <SEP> H <SEP> CH <SEP><alpha)<SEP>
<tb> 3.85-3.70 <SEP> m <SEP> 2 <SEP> H <SEP> CHOH <SEP> and <SEP> CHNH <SEP> (St <SEP> a) <SEP>
<tb><SEP> 3.48 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<tb> 2,12-2,00 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb> 1.70-1.08 <SEP> m <SEP> 12 <SEP> H <SEP> CH <SEP> and <SEP> CH2 <SEP> alipha
<tb><SEP> ticks <SEP> (Nle, Leu, Sta)
<tb> 0.92-0.71 <SEP> i <SEP> m <SEP> 15 <SEP> H <SEP> CH3 <SEP> (Nle, <SEP> Leu, <SEP> Sta)
<Tb>
SR 43123

Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 8.43-7.00 <SEP> m <SEP> 19 <SEP> H <SEP> 10 <SEP> H <SEP> C6H5
<tb><SEP> 4 <SEP> H <SEP> C5H4N
<tb> 5 <SEP> H <SEP> NHCO
<tb><SEP> 5.33 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH
<tb><SEP> 4.83 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta)
<Tb>

<tb> 4.72-3.70 <SEP> m <SEP> 7 <SEP> H <SEP> CH <SEP> (alpha)
<tb><SEP> CHOH <SEP> (Sta)
<tb><SEP> CHNH <SEP> (Sta)
<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3
<tb> 2,15-0,70 <SEP> m <SEP> 33 <SEP> H
<Tb>
SR 43282

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 8,41-7,02 <SEP> m <SEP> 19 <SEP> H <SEP> C6H5, <SEP> C5H4N, <SEP> NHCO
<tb><SEP> 4.85 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH
<tb><SEP> 4.61-4.12 <SEP> m <SEP> 4 <SEP> H <SEP> CH <SEP> aLpha
<tb><SEP> 3.84-3.68 <SEP> m <SEP> 2 <SEP> H <SEP> CHNH <SEP> and <SEP> CHOH <SEP> (Sta)
<tb><SEP> 3.49 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<tb><SEP> 3.45-3.18 <SEP> m <SEP> CH2C5H4N <SEP> (+ H20 <SEP> from
<tb><SEP> DMSO)
<tb><SEP> 3.02-2.61 <SEP> m <SEP> 4 <SEP> H <SEP> CH2C6H5
<tb><SEP> 2,13-2,0 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta) <SEP>
<tb><SEP> 1.68-1.04 <SEP> m <SEP> 12 <SEP> H <SEP> CH2 <SEP> (Nle) <SEP>;<SEP> eH <SEP> and
<tb> CH2 <SEP> (Sta <SEP> and <SEP> Leu)
<tb><SEP> 0.85-0.66 <SEP> m <SEP> 15 <SEP> H <SEP> CH3 <SEP> (Nle, <SE> Sta, <SE> Leu)
<Tb>
SR 43314

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 8.42-7.02 <SEP> m <SEP> 19 <SEP> H <SEP> C6H5, <SEP> C5H4N, <SEP> NHCO
<tb><SEP> 4.82 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH
<tb> 4.60-4.14 <SEP> m <SEP> 4 <SEP> H <SEP> CH <SEP> alpha
<tb> 3.85-3.70 <SEP> m <SEP> 2 <SEP> H <SEP> CHNH <SEP> and <SEP> CHOH <SEP> (Sta)
<tb><SEP> 3.53 <SEP> s <SEP> 2 <SEP> H <SEP> CH2C5H4N
<tb><SEP> 3.49 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<tb> 3.04-2.63 <SEP> m <SEP> 4 <SEP> H <SEP> CH2C6H5
<tb> 2,11-2,00 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta)
<tb> 1.72-1.08 <SEP> n <SEP> m <SEP> 12 <SEP> H <SEP> CH2 <SEP> (Nle) <SEP>;<SEP> CH <SEP> and
<tb><SEP> CH2 <SEP> (Sta <SEP> and <SEP> Leu) <SEP>
<tb> 0.82-0.64 <SEP> m <SEP> 15 <SEP> H <SEP> CH3 <SEP> (Ne, <SE> Sta, <SE> Leu)
<tb> SR 43366

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 7.1 <SEP> to <SEP> 8.75 <SEP> m <SEP> complex <SEP> 15 <SEP> H <SEP> 10 <SEP> H <SEP> C6H5, <SEP> 5 <SEP> NH
<tb> 5.35 <SEP> and <SEP> 5.5 <SEP> | <SEP> 2 <SEP> d, <SEP> J = 8 <SEP> Hz <SEP> 2 <SEP> H <SEP> 2 <SEP> H <SEP> alpha <SEP><Phg)<SEP>
<tb><SEP> 5 <SEP> n <SEP> m <SEP> 1 <SEP> H <SEP> OH <SEP> (Sta) <SEP>
<tb><SEP> 3.65 <SEP> m <SEP> n <SEP> 2 <SEP> H <SEP> H <SEP> aLpha <SEP> (Sta) <SEP>
<tb><SEP> 3.5 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP> ester
<tb><SEP> 1.35 <SEP> s <SEP> 9 <SEP> H <SEP> Boc
<Tb>
SR 43428 (2 isomers 7/3)

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb><SEP> 8.25-7.76 <SEP> n <SEP> 3 <SEP> H <SEP> NHCO
<tb><SEP> 7.39 <SEP> d <SEP> J = 8 <SEP> Hz <SEP> 1 <SEP> H <SEP> NHCO
<tb><SEP> 7.25-7.00 <SEP> m <SEP> 10 <SEP> H <SEP> C6H5
<tb> 7.00-6.89 <SEP> m <SEP> 2 <SEP> H <SEP> NHCO2
<tb><SEP> H <SEP> imidazole
<tb><SEP> 6.89 <SEP> | <SEP> 2 <SEP> s <SEP> 1 <SEP> H <SEP> H <SEP> imidazole <SEP>
<tb><SEP> 5.71
<tb> | <SEP> 5,32-4,0 <SEP> n <SEP> 5 <SEP> H <SEP> OH, <SEP> H <SEP> alpha <SEP> (Ala,
<tb><SEP> Phe, <SEP> Imidazole)
<tb> 4.0-3.67 <SEP> n <SEP> 4 <SEP> H <SEP> CHNH <SEP> and <SEP> CHOH
<tb><SEP> (AHPPA, <SEP> Sta)
<tb> 3.53
<tb><SEP>#<SEP><SEP> 2 <SEP> s <SEP> 3 <SEP> H <SEP> N-CH3
<tb><SEP> 3.44
<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3
<tb><SEP> 3.00-1.95 <SEP> m <SEP> 10 <SEP> H <SEP> CH2-C6H5 <SEP>
<tb><SEP> CH2 <SEP> imidazole
<tb><SEP> CH2CO <SEP> (AHPPA, <SEP> Sta)
<tb> 1.57-1.00 <SEP> m <SEP> 15 <SEP> H <SEP> (CH3) 3C, <SEP> CH3 <SEP> (Ala)
<tb><SEP> CH <SEP> and <SEP> CH2 <SEP> (Sta)
<tb><SEP> 0.77-0.69 <SEP> m <SEP> 6 <SEP> H <SEP> CH3 <SEP> (Sta)
<Tb>
SR 95508 and SR 95509 are characterized by a melting point after recrystallization from CH 2 Cl 2 and by their Rf in a 9: 1 CH 2 Cl 2 -MeOH mixture:
SR 95508 Fc = 2030C Rf = 0.23
- SR 95509 Fc = 1920C Rf = 0.44
The products according to the invention have been studied with regard to their therapeutic properties and in particular their enzymatic inhibitory action. More particularly, the compounds have been evaluated "in vitro" on the inhibition of the human Plasmatic Renal Plasma (ARP).

PZ V 867

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 8.36-7.07 <SEP> m <SEP> 19 <SEP> H <SEP> C5H4N, <SEP> C6H5, <SEP> NHCO
<tb><SEP> 4.84 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH
<tb> 4.57-4.12 <SEP> m <SEP> 4 <SEP> H <SEP> CH <SEP> alpha <SEP> (Phe, <SEP> Leu,
<tb><SEP> Nte)
<tb> 3.84-3.67 <SEP> m <SEP> 2 <SEP> H <SEP> CHN, <SEP> CHOH <SEP> (Sta)
<tb><SEP> 3.49 <SEP> s <SEP> 3 <SEP> H <SEP> OCli3 <SEP>
<tb> 3.03-2.57 <SEP> m <SEP> 6 <SEP> H <SEP> CH2C6H5, <SEP> CH2C5H4N <SEP>
<tb><SEP> 2.31 <SEP> t, <SEP> J <SEP> about <SEP> 2 <SEP> H <SEP> -CH2-CH2-CO <SEP>
<tb><SEP> 6 <SEP> Hz
<tb> 2,13-2,03 <SEP> m <SEP> 2 <SEP> H <SEP> CH2CO <SEP> (Sta) <SEP>
<tb> 1.70-1.09 <SEP> m <SEP> 12 <SEP> H <SEP> CH2 <SEP><NLe),<SEP> CH, <SEP> CH2
<tb><SEP> (Leu), <SEP> CH, <SEP> CH2 <SEP> (Sta) <SEP>
<tb> 0.85-0.66 <SEP> m <SEP> 15 <SEP> H <SEP> CH3
<Tb>
PZ V 875

<tb><SEP> Delta <SEP> Aspect <SEP> Integration <SEP> Attribution
<tb> 8.54-7.04 <SEP> n <SEP> 19 <SEP> H <SEP> H <SEP> aromatic <SEP> NHCO
<tb><SEP> 4.87 <SEP> d <SEP> J = 4 <SEP> Hz <SEP> 1 <SEP> H <SEP> OH
<tb> 4.61-4.14 <SEP> m <SEP> 4 <SEP> H <SEP> CH <SEP> alpha <SEP> (Phe, <SEP> Nle,
<tb><SEP> Leu)
<tb> 3.87-3.70 <SEP> m <SEP> 2 <SEP> H <SEP> CHNH, <SEP> CHOH <SEP> (Sta)
<tb><SEP> 3.50 <SEP> s <SEP> 3 <SEP> H <SEP> OCH3 <SEP>
<tb> 3.04-2.62 <SEP> m <SEP> 4 <SEP> H <SEP> CH2C6H5
<Tb>

<tb> 2.62-2.41 <SEP> m <SEP> CH2C5H4N <SEP> (+ DNSO)
<tb> 2.14-1.95 <SEP> m <SEP> 4 <SEP> H <SEP> CH2CO <SEP> tSta)
<tb><SEP> C5H4N-CH2CH2, <SEP> CH2 <SEP>
<tb> 1.78-1.10 <SEP> m <SEP> 14 <SEP> H <SEP> C5H4N-CH2-CH2CH2 <SEP>
<tb><SEP> CH2 <SEP> (Nle), <SEP> CH,
<tb><SEP> CH2 <SEP> (Sta, <SEP> Leu)
<tb> 0.91-0.67 <SEP> n <SEP><SEP> 15 <SEP> H <SEP><SEP> CH3 <SEP>
<Tb>
I - METHOD
Our method is inspired by GUYENE (J. Clin.

Endocrinol. Metab., 1976, 43, 1301, since the inhibition of A.R.P. is evaluated from a pool of human plasmas, rich in renin (15 to 20 mg of angiotensin I released per milliliter per hour) incubated at 37 C in the presence of increasing concentrations of the product to be studied.

 The angiotensin I released during the reaction (human plasmas contain and the substrate: angiotens; nogen, and the enzyme: renin) is measured by radioimmunoassay using a kit.

 Of course, an inhibitor of the PMSF (phenylmethylsulfonyl) fluoride conversion enzyme is added to the incubation medium.

 The experiments were carried out at pH 7.4 which is the physiological pH (phosphate buffer, incubation 60 min).

The results are expressed by the dose of compound evaluated in moles, which inhibits by 50 X (IC50) the activity Rénine
Human Plasma present in the absence of inhibitor.

 A solution of acetic acid in methanol (19/1 by volume) and a sodium hydroxide solution in methanol (2/1 by volume) are prepared. In an equivolumic mixture of these two solutions, a mother solution of the peptide at 0.001 M is prepared. The subsequent dilutions of the peptide are then carried out in the appropriate buffer according to the protocol described above.

 The amount of solvent present in a solution of the peptide at a concentration of less than 0.0001 M does not interfere with the results.

II - RESULTS
The results obtained with various products of the invention are shown in the following table where the IC.sub.50 of each molecule are shown with respect to their inhibition of Human Plasmatic Renin Activity at pH 7.4. From 5 to 10 doses were needed to determine these 1C50s. Pepstatin, as a reference substance, is always tested in parallel in each experiment. The results are expressed by their logarithmic value (-Log IC50).

<Tb>

<SEP> Inhibition <SEP> ARP <SEP> Human
<tb><SEP> -Log <SEP> IC50 <SEP> M
<tb><SEP> N <SEP> SR
<tb><SEP> Ph <SEP> 7.4
<tb> Pepstatin <SEP> 4.92
<tb> 42793 <SEP> 6.05
<tb> 42871 <SEP> 6.61
<tb> 42872 <SEP> 6.31
<tb> 42873 <SEP> 7.09
<tb> 42926 <SEP> 6.40
<tb> 42927 <SEP> 4.69
<tb> 42991 <SEP> 7.23
<tb> 43059 <SEP> 5.52
<tb> 43064 <SEP> 6.50
<tb> 43065 <SEP> 5
<tb> 43066 <SEP> 4.88
<tb> 43108 <SEP> 6.35
<tb> 43123 <SEP> 7.09
<tb> 43144 <SEP> 5.88
<tb> 43150 <SEP> 5.21
<tb> 43151 <SEP> 6.66
<Tb>
The toxicity of the products according to the invention is compatible with their therapeutic use.

Claims (4)

1. Peptide derivatives of formula

 where a = O, 1 or 2

<tb> - R1 represents one of the following groupings: <tb> in <SEP> which <SEP> 1 <tb> <SEP> z <tb> <SEP> R2 <SEP> O <SEP> R3 <SE> O <SEP> CH2 <SEP> O <sep> R1-NH-CH-C-NH-CH-C-N-CH-CHOH-CH2-C-X-Y-R4 <SEP> (I) <tb> <SEP> H

 where E = -H or -CH3 where n = 0, 1, 2 or 3  OH O  where D = -CH- or -C  where n = 0, 1, 2 or 3  acceptable.  of its salts of mineral or pharmaceutically organic acids  C1 to C6 alkyl; Z1 being other than isopropyl when X-Y represents Ala-Sta, or  - Nalk12, -OM, where M is a metal and Alk 'represents a group  Val-Sta, Abu-Sta, Phg-Sta-R4 represents one of the following groups: -OH, -OAlk ', -NH2,  4-amino-5-cyclohexyl-3-hydroxypenetanoic acid (ACHPA); X-Y is a dipeptide selected from Ala-Sta, Ala-Leu, Leu-Phe,  3-hydroxy-5-phenylpentanoic acid (AHPPA) or (3S, 4S) acid  3-hydroxy-6-methylheptanoic acid or (3S, 4S) -4-amino acid  of the amino acid statin, namely (3S, 4S) amino-4  the residue

Alk being as defined above - Z1 represents isopropyl, phenyl or cyclohexyl respectively forming with the radical R6 is one of the following radicals: phenyl, naphthyl or cycloalkyl having 3 to 6 carbon atoms; monocyclic heterocycle such as: imidazole, oxazole, thiazole or tetrazole, thiophene, pyrrole, triazole, pyridine, this heterocycle being optionally substituted by Alk or CF3,  be -CH-Alk  or (CH2) d, where d: 1, 2, 3, 4,  Alk being an alkyl group of Cl a C4 2) A is either a direct link  -S (O) eAlk, where e: O, 1, 2,  2-, 3- or 4-pyridyl radical;    -OH, -O-Alk, -OCH2C6H5, -OCH2-Pyr, where Pyr represents the  represent H or Alk or C6H5;  -CONR7R8, where R7 and R8 are different or the same and    -COOH, -C00-Alk, -COOCH2C6H5;  oxycarbonyl;  -NH2, -N (Alk) 2, -NHW, where W = protecting group such as benzyl  and R6 is one of the following remains:  be -CH-Alk  an A-R6 group in which: 1) A is either - (CH2) d, where d = 1, 2, 3, 4  alkenyl (C2 to C6)  an alkyl (C2 to C6)  or naphthyl or cyclohexyl or pyridyl; - R3 represents one of the following groupings:  R5 is a hydrogen atom or a phenyl radical  C6H5- (CH2) a-SO2-, where a = 0, 1 or 2, - Alk being an alkyl group of C1 to C4, - R2 represents the group (CH2) b R in which: b = 0, 1, 2, 3 or 4, and  Alk-SO2  Z-SO2-NHCH2CH2  BocNHCH2CH2-SO2  NH2CH2CH2-S02 2. Process for the preparation of a peptide according to claim 1, characterized in that from a compound of formula H-YOAlk in which Alk represents an alkyl of C1 to C4 and Y is chosen from the residues of the amino acids Sta , Leu and Phe, the various amino acids suitably protected are coupled step by step, the product obtained at each step being deprotected, according to known methods, before being subjected to a new coupling, each of the coupling operations being carried out. using either an activated ester of the amino acid to be coupled, or the N-protected amino acid in the presence of dicyclohexylcarbodiimide. 3. Pharmaceutical compositions characterized in that they contain a product according to claim 1 as an active ingredient. 4. Pharmaceutical compositions according to claim 3, usable in particular for the treatment of arterial blood pressure, characterized in that they contain from 1 to 1000 mg of product according to claim 1 per dosage unit in admixture with a pharmaceutical excipient.