JPH0517420A - Intermediates for substituted peptide compounds - Google Patents

Abstract

(57) [Summary] (Modified) [Objective] To provide an intermediate for producing a substituted peptide compound having pharmacological activity. [Structure] This intermediate has the following formula The compound represented by. [In the formula, halo is chloro or bromo, and R ₂ is R ₃ is hydrogen, lower alkyl, R ₁₄ is hydrogen, lower alkyl, lower alkoxy, etc., m
Is 0, 1, 2, 3 or 4, P is 1, 2 or 3, r is an integer of 1 to 4]

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an intermediate of a substituted peptide compound, and more particularly to an intermediate for producing a novel substituted peptide compound having pharmacological activity and salts thereof.

[0002]

The structure and effect of the present invention have the formula:

[Chemical 8] By using such a compound [II] represented by the following formula, a substituted peptide compound represented by the following formula [I] and salts thereof can be produced:

[Chemical 9] [Where X is

[Chemical 10]

[Chemical 11] Alkyl), azido, amino,

[Chemical 12] 1- or 2-naphthyl represented by,-(CH ₂ ) m-
(Cycloalkyl),

[Chemical 13] 1- or 2-naphthyloxy represented by
(Lower alkyl),

[Chemical 14] 1- or 2-naphthylthio represented by: R ₈ is keto,
halogen,

[Chemical 15] 1- or 2-naphthyloxy represented by
(Lower alkyl),

[Chemical 16] 1- or 2-naphthylthio represented by: R ₉ is keto or

[Chemical 17] R ₁₀ is halogen or —Y—R ₁₆ ; R ₁₁ , R ′ ₁₁ , R ₁₂ and R ′ ₁₂ are each independently hydrogen or lower alkyl,
Alternatively, R ′ ₁₁ , R ₁₂ and R ′ ₁₂ are hydrogen and R ₁₁ respectively.
Is

[Chemical 18] R ₁₃ is hydrogen, lower alkyl having 1 to 4 carbons, 1 to 1 carbons
4 lower alkoxy, alkylthio having 1 to 4 carbon atoms, chloro, bromo, fluoro, trifluoromethyl, hydroxy, phenyl, phenoxy, phenylthio or phenylmethyl; R ₁₄ is hydrogen, lower alkyl of 1 to 4 carbon atoms, carbon atoms 1 to 4 lower alkoxy, 1 to 4 carbon lower alkylthio, chloro, bromo, fluoro, trifluoromethyl or hydroxy; m is 0, 1, 2, 3 or 4; p is 1, 2 or 3 (provided that R is _When either ₁₃ or R ₁₄ is hydrogen, methyl, methoxy, chloro or fluoro, p is an integer greater than 1); R ₁₅ is hydrogen or 1 carbon atom.
~ 4 lower alkyl; Y is oxygen or sulfur; R ₁₆ is lower alkyl having 1 to 4 carbon atoms;

[Chemical 19] Alternatively, an unsubstituted 5- or 6-membered cyclic group formed by combining two R ₁₆ or a lower alkyl substituent having 1 to 4 ring-forming carbon atoms having 1 to 4 carbon atoms or di (lower ( Substituted 5- or 6-membered cyclic group having an alkyl) substituent having 1 to 4 carbon atoms; R ₄ is hydrogen, lower alkyl,

[Chemical 20] R ₅ is hydrogen, lower alkyl,

[Chemical 21] r is an integer from 1 to 4; R ₁₉ is lower alkyl, benzyl or phenethyl; R ₂₀ is hydrogen, lower alkyl, benzyl or phenethyl; R is hydrogen, lower alkyl, cycloalkyl,

[Chemical formula 22] _{, - (CH 2) 2 -NH} 2, - (CH 2) 3 -NH 2, - (CH 2) 4
_{-NH 2, - (CH 2)} 2 -OH, - (CH 2) 3 -OH, - (C
_{H 2) 4 -OH, - (} CH 2) 2 -SH, - (CH 2) 3 -SH , or _{- (CH 2) 4 -SH;} R 1 is hydrogen, lower alkyl, halo-substituted (lower) alkyl,

[Chemical formula 23] R ₂ is

[Chemical formula 24] R ₃ is hydrogen, lower alkyl,

[Chemical 25]

[Chemical formula 26] (m, R ₁₄ , p and r are as defined above); R ₆ is hydrogen, lower alkyl, benzyl, benzhydryl, R ₁₇ is hydrogen, lower alkyl, cycloalkyl or phenyl, R ₁₈ is hydrogen, lower alkyl, lower alkoxy or phenyl, or R ₁₇ and R ₁₈ are combined to form-(CH ₂ ) _{2
-, - (CH 2) 3} -, - CH = CH- or

[Chemical 27] R ₂₁ and R ₂₂ each independently represent hydrogen or lower alkyl; R ₂₃ represents lower alkyl].

In the formula [I], the terms used to define various symbols have the following meanings. Lower alkyl has 7 carbon atoms
Lower alkyl, which includes straight chain or branched groups not exceeding 4 and does not exceed 4 carbon atoms, is most preferable, and methyl and ethyl are most preferable. Similarly, lower alkoxy and lower alkylthio include lower alkyl as described above attached to oxygen or sulfur.

Cycloalkyl saturates saturated cyclic groups having 3 to 7 carbon atoms, of which cyclopentyl and cyclohexyl are most preferred.

Halogen includes chloro, bromo and fluoro.

Halo-substituted (lower) alkyl means a lower alkyl group as defined above in which one or more hydrogen has been replaced by chloro, bromo or fluoro, such as trifluoromethyl (which is preferred), pentafluoroethyl,
Includes 2,2,2-trichloroethyl, chloromethyl, bromomethyl and the like.

[0007]

[Chemical 28] Represents that each alkylene bridge can be bonded to all ring-forming carbon atoms.

Next, a method for producing the compound [I] will be described. The compound [I] has the formula:

[Chemical 29] [In the formula, halo represents halogen (preferably chloro or bromo). R ₂ and R ₃ have the same meaning as above], a ketone (intermediate of the present invention) [II], and a formula:

[Chemical 30] [Wherein X, R and R ₁ have the same meanings as defined above] is reacted with a peptide ester [III] in the presence of a base such as sodium hydrogencarbonate to remove the R ₆ ester group as necessary. It can be obtained by separating.

The ketone intermediate [II] of the present invention has the formula:

[Chemical 31] [In the formula, R ₄₀ represents a protecting group such as benzyloxycarbonyl, and halo represents halogen. R ₃ has the same meaning as above] with a ketone [IV] treated with hydrogen bromide and acetic acid, and then with this formula:

[Chemical 32] [Wherein R ₂ and halo have the same meanings as described above], and can be obtained by reacting the acid halide [V] in the presence of a base such as sodium hydrogencarbonate.

In the various reactions described above, R, R
Any one or all of ₁ , R ₃ and R ₅

[Chemical 33] If, the hydroxy, amino, imidazolyl, mercapto or guanidinyl functional groups in these groups should be protected during the reaction. Suitable protecting groups include benzyloxycarbonyl, t-butoxycarbonyl, benzyl,
Includes benzhydryl, trityl, etc., and nitro (for guanidinyl). The protecting group is removed by, for example, hydrogenation, treatment with acid or other known method to achieve reaction completion.

The compound [I] and its pharmacologically acceptable salts are hypotensive agents. These compounds are angiotensin I of the decapeptide angiotensin I.
It is useful in inhibiting conversion to I and thus reducing or ameliorating angiotensin-related hypertension. Angiotensin I is produced by the action of the enzyme renin on angiotensinogen and blood pseudoglobulin.
Angiotensin I is angiotensin converting enzyme (AC
E) converts to angiotensin II. Angiotensin II is a blood pressure-increasing active substance, and is related as a causative agent of various types of hypertension in various mammals (eg, humans). Compound [I] inhibits angiotensin converting enzyme and reduces or blocks the production of angiotensin II, a blood pressure-increasing active substance, whereby angiotensinogen → (renin) → angiotensin I.
→ Intervenes in the angiotensin II system. Thus, administration of a composition containing one compound [I] (or a mixture) can reduce angiotensin-dependent hypertension in a mammal (eg, human) with hypertension. To lower blood pressure, about 0.1-100mg (preferably about 1mg)
~ 50 mg) / kg (body weight) / day based on the dose of 1
It is appropriate to administer once a day, preferably in 2 to 4 divided doses. The active substance is preferably administered orally, but it may also be administered parenterally, such as subcutaneously, intramuscularly, intravenously or intraperitoneally.

[0012] (Enkephalinase) inhibitory activity and useful as an analgesic. Therefore, administration of a composition containing one or more mixtures of the compound [I] or a pharmaceutically acceptable salt thereof can alleviate the distress of mammals. Active compound about 0.1
~ 100 mg (preferably about 1-50 mg) / kg (body weight) / day based on the dose once a day, preferably 2
The desired analgesic activity is exhibited by administration in 4 divided doses. The composition is preferably administered orally, but may be administered parenterally, such as subcutaneously.

[0013]

EXAMPLES Next, the production method of the preferred compound of the present invention will be specifically described with reference to examples. LH-20 is pharmacia
Sephadex chromatography gel commercially available from Fine Chemicals. The temperature (° C.) in the examples may be simply expressed as “°”.

Example 1 Preparation of 1- [N-[(S) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -L-proline monohydrochloride :-( a) (S) -3-Amino-1-chloro-4-phenyl-2
-Production of butanone hydrobromide:-(S)-[3-chloro-2-oxo-1- (phenylmethyl) propyl] carbamic acid phenylmethyl ester 5
1.4 g are dissolved in a mixture of 252 ml acetic acid and 348 ml 3.45N hydrogen bromide in acetic acid and kept at room temperature for 1.5 hours. The reaction mixture is concentrated under reduced pressure, precipitated with ether and (S) -3-amino-1-chloro-4-phenyl-2.
36.6 g of butanone hydrobromide are obtained. m. p. (1
175-179 ° C at 75 ° C).

(B) (S) -N- [3-chloro-2-oxo-
Preparation of 1- (phenylmethyl) propyl] benzamide:-(S) -3-Amino-1-chloro-4-phenyl-2-butanone.hydrobromide 36.3 g (130.3 mmol)
Is suspended in 520 ml of dry tetrahydrofuran and 18.2 ml (130.3 mmol) of triethylamine with stirring for 10 minutes. The mixture is placed on an ice bath and 15.2 ml of benzoyl chloride are added, followed by 10.95 g of sodium hydrogen carbonate. After 5 minutes, remove the ice bath and keep the mixture at room temperature for 1.5 hours. The reaction mixture is concentrated under reduced pressure and the residue is taken up in 1000 ml of aqueous methanol (10% water). The precipitate was collected by filtration, washed with methanol, and then (S) -N-
25.3 g of [3-chloro-2-oxo-1- (phenylmethyl) propyl] benzamide are obtained. m. p. (160 ° C)
170-172 ° C. decomposition); [α] ²³ _D = -129 ° (in dimethylformamide, c = 1.7).

(C) of 1- [N-[(S) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -L-proline.1,1-dimethylethyl ester Production: -under argon, 50 ml of dimethylformamide, L
-Alanyl-L-proline-1,1-dimethylethyl ester 2.42 g (10 mmol), sodium hydrogen carbonate 0.840 g and (S) -N- [3-chloro-2-oxo-1- (phenylmethyl) Propyl] benzamide 3.0
Mix 1 g and stir overnight at room temperature. The reaction mixture is concentrated under reduced pressure to about half its original volume, the residue is taken up in ethyl acetate and washed with saturated sodium hydrogen carbonate to give 2.25 g of crude product. This material is ethyl acetate: methanol
Absorbed (95: 5), applied to a silica gel column (135 g) and eluted with ethyl acetate: methanol (95: 5) to give 1-
[N-[(S) -3-benzoylamino) -2-oxo-4
-Phenylbutyl] -L-alanyl] -L-proline
0.860 g of 1,1-dimethylethyl ester is obtained.

(D) Preparation of 1-N-[(S) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -L-proline monohydrochloride: in acetic acid 1- [N-[(S) -3 in 10 ml of 1.5N hydrochloric acid solution
0.740 g (1.46 mmol) of-(benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -L-proline.1,1-dimethylethyl ester was dissolved and kept at room temperature for 30 minutes. To do. It was concentrated, dissolved in water, filtered, lyophilized to 1- [N- (S) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-
0.600 g of alanyl] -L-proline monohydrochloride was obtained. m. p. 83-163 ° C; [α] ²⁵ _D = -109 ° (c = 1.04 in methanol); Rf 0.6 (butanol / acetic acid / water (4: 1: 1) on silica gel). Elemental analysis, calculated as C ₂₅ H ₂₉ N ₃ O ₅ .HCl.1.65H ₂ O; calculated value; C, 57.99%; H, 6.48%; N, 8.12
%; Cl, 6.85%, measured value; C, 57.99%; H, 6.39%; N, 8.09
%; Cl, 6.95%.

Example 2 Preparation of N- [N-[[(s) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-cyclohexylglycine monohydrochloride: -A) Preparation of N-cyclohexylglycine / 1,1-dimethylethyl ester: -Cyclohexylamine (70.35 ml) and sodium bicarbonate (12.9 g) suspended in 200 ml absolute ethanol with stirring in an ice bath. To do. These bromoacetic acid-1,1
-Dimethyl ester ester (20.78 ml) is added dropwise. Remove the ice bath. After 24 hours at room temperature, the reaction mixture is concentrated to dryness, poured into chloroform and washed with water. Crude product
(42 g) silica gel ethyl acetate / hexane (2: 1)
Chromatography eluting with 27.4 g of N
-Cyclohexylglycine-1,1-dimethylethyl ester is obtained.

B) Preparation of N-cyclohexyl-N- [N-[(phenylmethoxy) carbonyl] -L-alanyl] glycine.1,1-dimethylethyl ester: -N-[(phenylmethoxy) carbonyl] -L -Alanine
(4.46 g), N-cyclohexylglycine-1,1-dimethylethyl ester (4.26 g), hydroxybenzotriazole (3.06 g), dicyclohexylcarbodiimide (4.12 g) and triethylamine (2.8 ml).
Is stirred in 40 ml of dimethylformamide for 20 hours at room temperature. The reaction mixture was then concentrated under reduced pressure, poured into ethyl acetate, the dicyclohexylurea was filtered off, and the filtrate was 10%.
A neutralization wash with potassium bisulfate and saturated sodium bicarbonate gives 5.9 g of crude product. Crystallized from ether / hexane, 3.97 g of N-cyclohexyl-N-
[N-[(phenylmethoxy) carbonyl] -L-alanyl]
Glycine 1,1-dimethylethyl ester is obtained. m.
p. 104-105 °.

C) Preparation of N- (L-alanyl) -N-cyclohexylglycine.1,1-dimethylethyl ester:
Placing the ester product of (b) above (3.9 g) in methanol with palladium / carbon catalyst (10%, 700 mg),
Stir under a hydrogen atmosphere for 4 hours. The reaction mixture was filtered, concentrated to dryness and 2.65 g of crude N- (L-alanyl) -N-
Cyclohexylglycine · 1,1-dimethylethyl ester is obtained.

D) N- [N-[[(s) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-cyclohexylglycine.1,1-dimethylethyl ester Preparation of: -The crude ester product of (c) above (2.6 g), sodium bicarbonate (764 mg) and (s) -N- [3-chloro-2-oxo-l-of Example 1 (b). (Phenylmethyl) propyl] benzamide (2.75 g) is stirred in 25 ml of dimethylformamide for 20 hours. The reaction mixture is concentrated to dryness, taken up in ethyl acetate and washed with saturated sodium carbonate to give 4.7 g of crude product. Purification was carried out on a silica gel column eluting with ethyl acetate / methanol (99: 1) to give 1.5 g of N-
[N-[[(s) -3- (benzoylamino) -2-oxo-4
-Phenylbutyl] -L-alanyl] -N-cyclohexylglycine.1,1-dimethylethyl ester is obtained.

E) Preparation of N- [N-[[(s) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-cyclohexylglycine monohydrochloride:
-The ester product of (d) above (500 mg) in 5 ml of 1.5N
Treat with hydrochloric acid / acetic acid for 30 minutes, then concentrate to dryness at room temperature. The crude product is put in methanol and purified by LH-20 column to give 413 mg of product. This was made semi-crystalline in acetonitrile / ether and N- [N-[[(s)-
3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-cyclohexylglycine
The monohydrochloride is obtained. 154-157 ° (132 °), [α]
²³ _D = -67.4 ° (c = 1.35, methanol). Rf =
0.60 (small amount of impurity 0.92) (silica gel, chloroform / methanol / concentrated ammonia = 30: 10: 2). Elemental analysis (as _{C 28 H 35 N 3 O 5} · HCl · H 2 O) Calculated; C61.35, H6.99, N7.67, Cl
6.47 Found: C61.08, H6.79, N7.65, Cl
6.46

Example 3 Preparation of N- [N-[[(s) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-phenylglycine monohydrochloride: -A) Preparation of N-phenylglycine.1,1-dimethylethyl ester: -ether (triethylamine (11.25 in 100 ml)
A solution of g, 0.11 mol) and aniline (9.3 g, 0.10 mol) is cooled to 0 ° in an ice bath under an atmosphere of argon. Bromoacetic acid 1,1-dimethylethyl ester (18 g, 0.093 mol) is added to this over 30 minutes. The resulting mixture is stirred at 0 ° for 1 hour, then warmed to room temperature and stirred overnight. The solution is filtered, rinsed with ether and the filtrate concentrated to give 6.9 g of a yellow oil.
Rf = 0.6, 0.7 (silica gel, ethyl acetate). LP
Hexane / ethyl acetate (7: 3) as eluent in S-1
Chromatography to give 2.3 g of N-phenylglycine.1,1-dimethylethyl ester as a pale yellow liquid. Rf = 0.7 (silica gel, ethyl acetate).

B) N-phenyl-N- [N-[(phenylmethoxy) carbonyl] -L-alanyl] glycine.1,1
-Preparation of dimethyl ethyl ester: -N-[(phenylmethoxy) carbonyl] -L-alanine (2.8 g, 12.7) in dry tetrahydrofuran (50 ml).
(mMole) solution is cooled in a dry ice-ethanol bath under argon. N-methylmorpholine (1.2
8 g, 12.7 mmol) and isobutyl chloroformate (1.73 g, 12.7 mmol) are added. 20 minutes later, N
-Phenylglycine / 1,1-dimethylethyl ester
(3.7 g, 12.7 mmol) is added. The resulting mixture is stirred at −20 ° for 1 hour and then at room temperature overnight. The mixture is partitioned between ethyl acetate and 1N hydrochloric acid. The organic layer washed successively with 1N- hydrochloric acid and 10% sodium bicarbonate, dried (MgSO _4), and concentrated. Chromatography on LPS-1 eluting with a gradient of ethyl acetate / hexane (3: 1 → 1: 1) gave 4.0 g of N-phenyl-N-.
[N-[(phenylmethoxy) carbonyl] -L-alanyl]
Glycine 1,1-dimethylethyl ester is obtained as a clear oil. Rf = 0.4 (silica gel, ethyl acetate).

C) Production of N- (L-alanyl) -N-phenylglycine.1,1-dimethylethyl ester: -Ester product (4.0 g, 9.7 mmol) of (b) above ( 125 ml) solution and 10% palladium on carbonic acid catalyst are stirred under a stream of hydrogen for 18 hours. The solution is filtered, concentrated, dissolved in ethyl acetate and extracted with 1N hydrochloric acid. The aqueous layer is treated with sodium bicarbonate until basic and extracted with ethyl acetate. Dry the collected ethyl acetate extracts
(MgSO ₄ ), concentrated to give 1.3 g of N- (L-alanyl).
-N-Phenylglycine.1,1-dimethylethyl ester is obtained as a white solid. Rf = 0.52 (small amount spot 0.64) (silica gel, ethyl acetate / methanol = 1:
1).

D) N- [N-[[(s) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-phenylglycine.1,1-dimethylethyl ester Preparation of :-( s) -N of Example 1 (b) in dry dimethylformamide.
-[3-chloro-2-oxo-1- (phenylmethyl) propyl] benzamide (1.4 g, 4.7 mmol) and N-
Sodium bicarbonate (0.38 g, 4.7 mmol) and sodium iodide were added to a stirred solution of (L-alanyl) -N-phenylglycine.1,1-dimethylethyl ester (1.3 g, 4.7 mmol). (0.7 g, 4.7 mmol) is added. After stirring overnight at room temperature, the mixture was concentrated, dissolved in ethyl acetate,
Filter. Wash the filtrate with 10% sodium bicarbonate and dry
(MgSO ₄ ) and concentrated to a yellow oil. LPS-1
Chromatography with a gradient of ethyl acetate / hexane (1: 1) → ethyl acetate at 1.8 g of N- [N-
[[(s) -3- (Benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-phenylglycine.1,1-dimethylethyl ester is obtained. Rf = 0.3
4 (silica gel, ethyl acetate).

E) Preparation of N- [N-[[(s) -3- (benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-phenylglycine monohydrochloride:- A solution of the ester product of (d) above (1.6 g, 2.9 mmol) in hydrochloric acid / acetic acid (1.77N, 17.0 ml) is dried at room temperature for 30 minutes. The solution is concentrated and the residue is triturated with ether to give a pale yellow solid. Recrystallized from methanol / ether to give 0.84 g of N- [N-[[(s) -3
-(Benzoylamino) -2-oxo-4-phenylbutyl] -L-alanyl] -N-phenylglycine monohydrochloride is obtained as a white crystalline solid. m. p. 147-159 ° (decomposition). Rf = 0.8 (silica gel, butanol / acetic acid / water = 1: 1: 1). [α] _D = -12.7 ° (c = 1.5, methanol). Elemental analysis _{(C 28 H 29 N 3 O} 5 · HCl · 0.65H 2 O ) Calculated values: C62.77, H5.89, N7.84, Cl
6.62 Found: C62.77, H5.70, N7.84, Cl
6.12

Example 4 (s) -1- [N-[[3- (benzoylamino) -2-oxo-4-phenylbutyl] -N-methyl-L-alanyl]-
Preparation of L-proline monohydrochloride: -a) Preparation of N-[(phenylmethoxy) carbonyl] -L-alanine: -L-alanine (89.1 g, 1 mol) in 2N-sodium hydroxide (500 ml) Dissolve in and cool to 0 °. To this was added benzyl chloroformate (204.5 g, 1.2 mol) and 4N sodium hydroxide (250 ml) simultaneously dropwise over 1 hour. The reaction mixture is stirred overnight (0 ° to room temperature) and washed with ethyl acetate (500 ml x 2). The aqueous portion was acidified to pH 2.0 with 6N-hydrochloric acid, and ethyl acetate (600
Extract with ml x 3). Stir the collected ethyl acetate extracts (N
a ₂ SO ₄ ), concentrated on a rotary evaporator and the solid residue triturated with petroleum ether to give 194.0 g of N-
[(Phenylmethoxy) carbonyl] -L-alanine is obtained as a white solid.

B) Preparation of N-methyl-N-[(phenylmethoxy) carbonyl] -L-alanine: -N-[(phenylmethoxy) carbonyl] -L-alanine (22.3 g, in tetrahydrofuran (250 ml)) 0.1 mol) and methyl iodide (50 ml, 0.8 mol) cold (0 °)
To the solution is added sodium hydride suspension (14.25 g, 0.3 mol) with careful and gentle stirring. The suspension was stirred under a nitrogen atmosphere overnight (0 ° → room temperature), poured slowly into saturated sodium bicarbonate (200 ml) and washed with ethyl acetate.
Dilute with (300 ml) and separate layers. The organic layer is extracted again with saturated sodium bicarbonate. 10% of the collected aqueous layer
Acidify to pH 2.0 with potassium bisulfate and extract with ethyl acetate. The combined ethyl acetate extracts are dried (Na ₂ SO ₄ ).
And concentrated in vacuo to a dark oily residue (23.0 g). The crude acid is treated with dicyclohexylamine (20 ml) in ether (150 ml). The resulting crude dicyclohexylamine salt was collected (37.0 g), recrystallized from chloroform / ether (35.0 g), and partitioned between 1N-hydrochloric acid / ethyl acetate to convert it back to an acid to give a pale yellow oil. It is left to crystallize (17.4 g). Recrystallisation (11.2 g) from ethyl acetate / petroleum ether gives 4.0 g of N-methyl-N-[(phenylmethoxy) carbonyl] -L-alanine as a white crystalline product. m. p. 65-66.5 °,
[α] ²⁵ _D = -31.1 ° (c = 2, acetic acid).

C) 1- [N-methyl-N-[(phenylmethoxy) carbonyl] -L-alanyl] -L-proline.
Preparation of 1,1-dimethylethyl ester: -N-methyl-N- in distilled tetrahydrofuran (50 ml)
[(Phenylmethoxy) carbonyl] -L-alanine (4.
74 g, 20 mmol) in a solution of L-proline 1,1-dimethylethyl ester (3.42 g, 20 mmol), hydroxybenzotriazole hydrate (3.06 g, 20 mmol)
And dicyclohexylcarbodiimide (4.12 g, 2
0 mmol) is added. The reaction mixture is stirred overnight, the precipitated dicyclohexylurea is filtered off and the filtrate is concentrated. The residue was dissolved in ethyl acetate (50 ml) and saturated sodium bicarbonate
(Twice), washed with 10% potassium bisulfate (twice) and water (twice), dried (Na ₂ SO ₄ ), concentrated and concentrated to 6.4 g of 1- [N.
-Methyl-N-[(phenylmethoxy) carbonyl] -L-
Alanyl] -L-proline.1,1-dimethylethyl ester is obtained as an oily residue.

D) 1- (N-methyl-L-alanyl) -L
Preparation of proline 1,1-dimethylethyl ester: -Ester product of (c) above (6.4 g, 16.4 mmol) and 0.8 g of 10 in ethanol (95%, 150 ml).
The% palladium / carbon catalyst mixture is hydrogenated at atmospheric pressure overnight. The catalyst is filtered off and the filtrate is evaporated.
The oily residue obtained is dried under high vacuum to solidify to an oily solid residue (3.8 g). Triturated with ether to give 1.5 g of 1- (N-methyl-L-alanyl) -L
-Proline 1,1-dimethylethyl ester monohydrochloride is obtained as a white solid. Rf = 0.44 (silica gel, 2
0% methanol / chloroform). [α] ²⁵ _D = −102.
1 ° (c = 2, acetic acid). 2.3 g of 1-from the ether filtrate
(N-Methyl-L-alanyl) -L-proline.1,1-
Dimethyl ethyl ester is obtained as an oil. Rf = 0.4
4 (silica gel, 20% methanol / chloroform).
[α] ²⁵ _D = -101.6 ° (c = 2, acetic acid).

E) (s) -1- [N-[[3- (benzoylamino) -2-oxo-4-phenylbutyl) -N-methyl-L-alanyl] -L-proline.1,1- Preparation of dimethylethyl ester: 1- (N-methyl-L-alanyl) -L-proline.1,1-dimethylethyl ester (2.1 g, 8.19 mmol) in dimethylformamide (15 ml), carried out Example 1 (b)
(s) -N- [3-Chloro-2-oxo-1- (phenylmethyl) propyl] benzamide (2.46 g, 8.19 mmol), excess sodium bicarbonate and sodium iodide
The reaction mixture of (1.22 g, 8.10 mmol) is stirred overnight at room temperature under nitrogen atmosphere. The reaction mixture is concentrated, the residue is partitioned between water / ethyl acetate, the layers are separated and the aqueous layer is extracted again with ethyl acetate. The combined organic extracts are washed with saturated sodium bicarbonate and water, dried (Na ₂ SO ₄ ) and concentrated to an oily residue (3.5g). Flash chromatography (silica gel 200 g, 1% methanol / ethyl acetate) gives 2.8 g of (s) -1- [N-[[3- (benzoylamino) -2-oxo-4-phenylbutyl] -N. −
Methyl-L-alanyl] -L-proline.1,1-dimethylethyl ester is obtained as a yellow oil.

F) of (s) -1- [N-[[3- (benzoylamino) -2-oxo-4-phenylbutyl] -N-methyl-L-alanyl] -L-proline monohydrochloride Preparation: -2 g of the ester product of (e) above (1.4 g, 2.7 mmol)
Treat with N-hydrochloric acid / acetic acid (20 ml). After stirring for 2 hours at room temperature, the reaction mixture was concentrated under reduced pressure and the resulting oily residue was triturated with ether (4 times) to give 1.05 g of (s)-
1- [N-[[3-benzoylamino) -2-oxo-4-
Phenylbutyl] -N-methyl-L-alanyl] -L-proline monohydrochloride is obtained as an off-white solid. m. p.
125-135 °, Rf = 0.24 (silica gel, n-butanol / acetic acid / water = 4: 1: 1). [α] ²⁵ _D = -87 ° (c
= 1, methanol). Elemental analysis _{(C 26 H 31 N 3 O} 5 · HCl · 0.7H 2 O ) Calculated values: C60.68, H6.41, N8.16, Cl
6.88 Found: C60.68, H6.36, N7.95, Cl
6.48

Example 5 (s) -1- [N- [3- (benzoylamino) -2-oxo-4-phenylbutyl] -4-phenylglycyl] -L-
Preparation of proline hydrochloride (20: 3):-a) Preparation of 1- (bromoacetyl) -L-proline.1,1-dimethylethyl ester: -L-proline.1, in methylene chloride (250 ml) Cooling of 1-dimethylethyl ester (34.2 g, 0.2 mol)
To the (-10 °) solution, diisopropylethylamine (3
8.3 ml, 0.22 mol) and bromoacetyl chloride (1
6.5 ml, 0.2 mol) are added dropwise over 20 minutes, keeping the temperature between -10 ° and -5 °. The dark reaction mixture is stirred overnight (-10 ° to room temperature) and concentrated under reduced pressure. The oily residue was redissolved in ethyl acetate, saturated sodium bicarbonate (2 times), 10% potassium bisulfate (2 times) and water.
Wash (twice), dry (Na ₂ SO ₄ ) and concentrate to a dark oily residue (28.0 g). By flash chromatography (LPS-1 silica gel, 10% ethyl acetate / methylene chloride), 11.0 g of 1- (bromoacetyl) -L-
Proline.1,1-dimethylethyl ester is obtained as a pale yellow oil.

B) Preparation of 1- (N-phenylglycyl) -L-proline.1,1-dimethylethyl ester: 1- (Bromoacetyl) -L-proline.1, in distilled tetrahydrofuran (40 ml) 1-dimethyl ethyl ester
To a solution of (2.1 g, 7.5 mmol) aniline (1.5 g,
15 mmol) and the reaction mixture is stirred under nitrogen overnight. The reaction mixture was diluted with ethyl acetate (200 ml), washed with saturated sodium bicarbonate (50 ml x 2) and water (twice),
Dry (Na ₂ SO ₄ ) and concentrate under reduced pressure to a dark oily residue (4.0
g). Flash chromatography (LPS-1
Silica gel, 10% ethyl acetate / methylene chloride),
2.2 g of 1- (N-phenylglycyl) -L-proline.1,1-dimethylethyl ester are obtained as a dark oil.
It is dried under high vacuum to solidify.

C) (s) -1- [N- [3- (benzoylamino) -2-oxo-4-phenylbutyl) -N-phenylglycyl] -L-proline.1,1-dimethylethyl ester Preparation of 1- (N-phenylglycyl) -L-proline.1,1-dimethylethyl ester (1.06 g, 3.5 mmol) in dimethylformamide (10 ml), Example 1 (b) (S)-
N- [3-chloro-2-oxo-1- (phenylmethyl)
Propyl] benzamide (1.06 g, 3.5 mmol), excess sodium bicarbonate and sodium iodide (0.52 g,
The reaction mixture (3.5 mmol) is stirred overnight at room temperature under a nitrogen atmosphere. The reaction mixture was poured into water (50 ml), ethyl acetate
Extract with (50 ml x 3). Wash the combined ethyl acetate extracts with saturated sodium bicarbonate (2 times) and water (3 times) and dry.
(Na ₂ SO ₄ ) and concentrated under reduced pressure to a dark oily residue (2.0
g) is obtained. Flash chromatography (LPS-1
Silica gel, 5% ethyl acetate / methylene chloride → 15% ethyl acetate / methylene chloride), 0.3 g of (s) -1- [N
-[3- (benzoylamino) -2-oxo-4-phenylbutyl] -N-phenylglycyl] -L-proline
1,1-Dimethylethyl ester is obtained as a pale yellow foam.

D) (s) -1- [N- [3- (benzoylamino) -2-oxo-4-phenylbutyl] -N-phenylglycyl] -L-proline.hydrochloride (20: 3) Preparation of: -Ester product of (c) above (0.28 g, 0.49 mmol)
Is treated with 2N hydrochloric acid / acetic acid. After stirring for 1 hour at room temperature,
The reaction mixture was concentrated under reduced pressure and the resulting oily residue was triturated (4 times) with ether to give 0.14 g of (s) -1.
-[N- [3- (Benzoylamino) -2-oxo-4-phenylbutyl] -N-phenylglycyl] -L-proline.hydrochloride (20: 3) is obtained as an off-white solid. m. p.
110-140 °, Rf = 0.76 (small spot 0.5
3) (silica gel, n-butanol / acetic acid / water = 3: 1:
1). Elemental analysis _{(C 30 H 31 N 3 O} 5 · 0.15HCl · 0.5H 2
Calculated: C68.22, H6.13, N7.95, Cl
1.00 Found: C68.22, H6.00, N8.25, Cl
0.99

Examples 6-27 Ketones in column I below, acid chlorides in column II and column III
The ester product of column IV is obtained in the same manner as in Examples 1 to 5 except that the peptide of 4 is used. Removal of the R ₆ ester group and other protecting groups gives the corresponding final product in acid form.

[0039]

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

[Table 4]

[0044]

[Table 5]

The R ₁ protecting group of Examples 11, 13 and 14, the R ₃ protecting group of Examples 15 and 17, and the R ₅ protecting group of Examples 18 and 20-22 are removed as the final step of the synthesis. R ₆ ester group of Example 24 to 27 was not removed.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C07D 401/12 8829-4C 405/12 8829-4C 409/12 8829-4C (72) Inventor Eric・ M Gordon No.126 Raining Avenue, Pennington, New Jersey, USA

Claims (3)

[Claims] 1. The formula: [Wherein halo is chloro or bromo; R
₂ is [Chemical 2] R ₃ is hydrogen, lower alkyl, or R ₁₄ is hydrogen, lower alkyl having 1 to 4 carbons, 1 to 4 carbons
4 lower alkoxy, C1-4 lower alkylthio, chloro, bromo, fluoro, trifluoromethyl or hydroxy; m is 0, 1, 2, 3 or 4; p is 1, 2 or 3 (provided that R ₁₄ is When hydrogen, methyl, methoxy, chloro or fluoro, p is an integer greater than 1); r represents an integer of 1 to 4]. 2. R ₂ is R ₃ is m is 0, 1 or 2; R ₁₄ is hydrogen, methyl, methoxy, methylthio, chloro,
The compound of claim 1 which is bromo, fluoro or hydroxy. 3. R ₂ is R ₃ is The compound of claim 2 wherein halo is chloro.