KR890002173B1 - Substituted dipeptides process for their preparation - Google Patents

Abstract

Substituted dipeptides, strengthening the alleviating effect, were prepd. Thus, a soln. contg. 13.4mM L-3-(3-thienyl)alanyl-Lalanine trifluoroacetate and 56.1mM 2-oxo-4-phenylbutyrate was adjusted to pH 6.8 with 1N-NaOH and treated with 34.8 mM Nacyanoborohydride. After stirring for 64 hrs at room temp., the soln. was adjusted to pH 2.9 with 1N-HCl. The resulting gum was dissolved in 20ml acetonitrile and diluted with 10ml ether to give N-(1-carboxy-3-phenylpropyl)-L-3- (3-thienyl)-alanyl-L-alanine.

Description

Substituted Dipeptides and Methods for Making the Same

The present invention relates to certain novel substituted dipeptides and methods for their preparation. The invention also relates to pharmaceutical compositions containing substituted dipeptides, including the novel dipeptides according to the invention.

Two peptides, H-Tyr-Gly-Gly-Phe-Met-OH (methionine-enkephalin) and H-Tyr-Gly-Gly-Phe-Leu-OH (leucine-encaphalin), both of which are commonly referred to as the generic name "enkephalin A natural opiate receptor agonist known as "enkephalin", thought to be a mixture of "included", has been shown to cause significant analgesia in rats when injected into the rat ventricle. [Beluzzic et al, Nature, 260, 625 (1976).

Enkephalins, which are naturally produced in the body of warm-blooded animals, have also been found to be inactivated by a group of enzymes known as enkephalinase, which is naturally produced in such bodies. Therefore, it is important to find a compound capable of inhibiting or alleviating the above-mentioned inactivation action of enkephalinase.

One aspect of the present invention relates to substituted dipeptides of the general formula (I) and pharmaceutically acceptable salts thereof.

(저급 알킬),

[여기에서, R₂₁및 R₂₁은 동일하거나 상이하며, 수소, 저급알킬, 아릴 및 아르알킬 중에서 선택되거나, R₂₀및 R₂₁은 함께, 환 헤테로 원자로서 산소를 함유할 수 있는 포화된 5 내지 7원환을 형성한다], 또는 그룹

(여기에서, R₁₀은 수소, 저급 알킬 또는 벤질이고, R₁₁은 하이드록시, 알콕시, 벤질옥시, 저급 알킬, 아릴 또는 벤질이다)이며; R₃는 수소 또는 저급 알킬이고; X는

또는

이며, 여기에서 q는 0 또는 1이고, R₄는 R₁에 대해 정의된 그룹, 또는 인돌린(예:3-인돌린), 인돌릴알킬(예:3-인돌릴알킬), 아미노메틸페닐-저급알킬 3-티아나프테닐메틸 및 테트라하이드로 나프틸 메틸 중에서 선택되며: R₅는 수소 또는 저급 알킬이고; y는 0, 1, 2 또는 3이며; R₆, R₇및 R₈은 R₄에 대해 정의된 그룹 중에서 선택되고, R₉는 R₂에 대해 정의된 그룹 중에서 선택되며, y가 2 또는 3인 경우에, R₇및 R₈은 동일하거나 상이한 탄소원자상에 존재할 수 있으며, 단 x가

이고, y가 0이며, R₂가

이 아닌 경우에는, 다음 조건중 하나 또는 그 이상이 적용된다: a) R₁은 피리딜, 티에닐, 푸라닐, 나프릴 저급알킬, 나프릴 또는 아르알킬 티오이고: b) R₃는 저급 알킬이고: c) R₄는 푸라노메틸, 사이클로저급알킬, 아릴저급알킬, 티에닐메틸, 테트라하이드로나프틸-메틸, 1-또는 2-나프틸메틸, 3-티아나프테닐-메틸, 사이클로저급알킬메틸, 저급알콕시저급알킬, 아르알콕시저급알킬, 아릴, 치환된 아릴(여기에서, 치환체는 할로겐, 저급알킬, 하이드록실, 저급알콕실, 할로저급알킬, 니트로, 모노- 또는 디-저급알킬아미노 및 시아노 중의 하나 또는 그 이상이다), 또는 본 조건에서 정의된 아릴 치환체(단, 하이드록실은 제외)하나 또는 그 이상으로 아릴 부위에서 치환된 아릴메틸이고: d) R₆는 아실아미노 저급알킬, 모노- 또는 디-저급알킬아미노 저급알킬, 또는 R₄에 대해 상기 (c)에서 언급된 그룹(단, 아릴은 제외)중 하나이다.Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkyl amino-lower alkyl, di-lower alkylamino Lower alkyl, acyl amino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl are Alkyl, alkylthio-lower alkyl, aralkyl oxyalkyl, iralkylthio-alkyl or hetero aryloxyalkyl, wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy amino, aminomethyl, carboxyl, Cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic groups The group is any one or more selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkylamino, di-lower alkylamino, acylamino, halogeno, halogeno loweralkyl, cyano and / or sulfonamino Substituted); R ₂ is —COOH, —COO— (lower alkyl), —COO— (aryl-lower alkyl), —COO— (aryl),

(Lower alkyl),

[Wherein R ₂₁ and R ₂₁ are the same or different and are selected from hydrogen, lower alkyl, aryl and aralkyl, or R ₂₀ and R ₂₁ together are saturated from 5 to 5 which may contain oxygen as a ring hetero atom; Forms a seven-membered ring], or a group

Wherein R ₁₀ is hydrogen, lower alkyl or benzyl and R ₁₁ is hydroxy, alkoxy, benzyloxy, lower alkyl, aryl or benzyl; R ₃ is hydrogen or lower alkyl; X is

or

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolin (eg 3-indoline), indolylalkyl (eg 3-indolylalkyl), aminomethylphenyl- Loweralkyl 3-thianaphthenylmethyl and tetrahydro naphthyl methyl is selected from: R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ , R ₉ is selected from the group defined for R ₂ , and if y is 2 or 3, R ₇ and R ₈ are the same Or different carbon atoms, provided that x is

, Y is 0, and R ₂ is

If not, one or more of the following conditions apply: a) R ₁ is pyridyl, thienyl, furanyl, napryl loweralkyl, napryl or aralkyl thio: b) R ₃ is lower alkyl And c) R ₄ is furanomethyl, cycloloweralkyl, arylloweralkyl, thienylmethyl, tetrahydronaphthyl-methyl, 1- or 2-naphthylmethyl, 3-thianaphthenyl-methyl, cycloloweralkyl Methyl, lower alkoxy lower alkyl, aralkoxy lower alkyl, aryl, substituted aryl, wherein the substituents are halogen, lower alkyl, hydroxyl, lower alkoxyl, halo lower alkyl, nitro, mono- or di-lower alkylamino and One or more of cyano), or one or more aryl substituents as defined herein (except for hydroxyl) and arylmethyl substituted at one or more aryl moieties: d) R ₆ is an acylamino loweralkyl, Mono- or di-lower alkylamino lower alkyl, Or one of the groups mentioned in (c) above for R ₄ , except aryl.

이고, R₁이 수소, 치환되거나 비치환된 아릴, 헤테로아릴(여기에서, 헤테로원자는 O, S 또는 N이다), 또는 치환되거나 비치환된 저급 알킬[여기에서, 치환된 저급 알킬의 부위의 치환체는 할로겐, 치환되거나 비치환된 아릴, 헤테로아릴(여기에서, 헤테로원자는 O, S 또는 N이다). 치환되거나 비치환된 아릴티오, 아미노, 저급 알카노일-아미노, 모노-및 디-저급알킬아미노, 치환되거나 비치환된 아릴옥시, 및 치환되거나 비치환된 아르알킬티오(여기에서, 치환된 아릴 그룹 또는 부위상의 치환체는 할로겐, 저급알킬, 하이드록실, 저급알콕실, 폴리할로저급알킬, 니트로, 모노- 또는 디-저급알킬아미노 및 시아노 중의 하나 또는 그 이상으로 선택된다)중의 하나 또는 그 이상으로 선택된다]이며: R₂가

, 카복실, -COO-저급알킬, -COO-아릴, -COO-아르알킬 (여기에서, 아릴, 또는 아르알킬 그룹의 아릴 부위는 R₁에서와 같이 치환될 수 있다).The most preferred sub-class of the compounds of the invention is that X is

And R ₁ is hydrogen, substituted or unsubstituted aryl, heteroaryl, wherein the heteroatom is O, S or N, or substituted or unsubstituted lower alkyl, wherein the site of substituted lower alkyl Substituents are halogen, substituted or unsubstituted aryl, heteroaryl, wherein the heteroatom is O, S or N. Substituted or unsubstituted arylthio, amino, lower alkanoyl-amino, mono- and di-lower alkylamino, substituted or unsubstituted aryloxy, and substituted or unsubstituted aralkylthio, wherein substituted aryl groups Or a substituent on a site is selected from one or more of halogen, lower alkyl, hydroxyl, lower alkoxyl, polyhalo lower alkyl, nitro, mono- or di-lower alkylamino and cyano) Is selected from: R ₂ is

, Carboxyl, -COO-loweralkyl, -COO-aryl, -COO-aralkyl, wherein the aryl moiety of the aryl or aralkyl group may be substituted as in R ₁ .

Wherein R ₂₀ and R ₂₁ are the same or different and are hydrogen, lower alkyl, unsubstituted or substituted aryl, wherein the substituents are as defined for R ₁ above for the sub-class of the compounds of the present invention; Or an unsubstituted or substituted aralkyl wherein the substituent of the aryl moiety is as defined for R ₁ above for the subclass of the compounds of the invention: or R ₂₀ and R ₂₁ together with the nitrogen atom, Forms a saturated 5 to 7 membered ring which may contain oxygen as part of the ring; and R ₄ is hydrogen, furanomethyl, thienylmethyl, tetrahydronaphthylmethyl, 1- or 2-naphthylmethyl. 3-thianaphthenylmethyl, lower alkyl, cyclolower alkyl, cyclolower alkylmethyl, hydroxy lower alkyl, acylamino-lower alkyl, amino-lower alkyl, mono- or di-lower alkylamino-lower alkyl, lower alkoxy lower Alkyl, Aralkoxy Loweralkyl, wherein the aryl moiety may be substituted as defined in R ₁ above for the Sub-Class of the Compounds of the Invention, 3-Indolyl Loweralkyl, Aralkyl (eg Benzyl) , Aryl (e.g. phenyl), substituted aralkyl (e.g. substituted benzyl), or substituted aryl (e.g. phenyl), wherein the substituent is an aryl substituent at R ₁ above for a subclass of the compounds of the present invention. R ₆ , R ₇ and R ₈ are selected from the group defined above for R ₄ and when y is 0, 1, 2 or 3 and y is 2 or 3, then R is ₇ and R ₈ may be present on the same or different carbon atoms: R ₉ is defined above for R ₂ And pharmaceutically acceptable salts thereof.

(여기에서, R₂₀및 R₂₁중 하나는 수소이고, 다른 하나는 저급알킬이거나, 또는 이들이 부착되어 있는 질소원자와 함께, 헤테로원자로서 산소를 함유하는 포화된 5 내지 7원환을 형성한다)인 화합물 및 이의 약제학적으로 허용되는 염이다.Another preferred sub-class of the compounds of the invention is that y is 1, 2 or 3, R ₁ is aryl loweralkyl, R ₂ is carboxyl, -COO-loweralkyl, or -COO-arylloweralkyl, R ₃ Is hydrogen, R ₄ is benzyl, 1- or 2-naphthylmethyl, loweralkyl, substituted or unsubstituted phenyl-loweralkyl, or 2- or 3-thienylmethyl, R ₅ , R ₆ , R ₇ And R ₈ is hydrogen, R ₉ is carboxyl, or

Wherein one of R ₂₀ and R ₂₁ is hydrogen and the other is lower alkyl or together with the nitrogen atom to which they are attached form a saturated 5 to 7 membered ring containing oxygen as a hetero atom Compounds and their pharmaceutically acceptable salts.

Another preferred sub-class of the compounds of the invention is that y is 1, R ₁ is 1-naphthylmethyl, paratolylmethyl, benzyl or phenylethyl, R ₂ is carboxy and R ₄ is paratolylmethyl or benzyl Phosphorus compounds and pharmaceutically acceptable salts thereof. Typically the most preferred compounds are (L) -N- (1-carboxy-3-phenylpropyl)-(L) -phenylalanyl-β-alanine, or (L) -N- (1-carboxy-2-phenyl Ethyl)-(L) -phenylalanyl-β-alanine.

이고, y가 바람직하게는 0이며, R₁이 일반식(I)에 대해 상기 정의된 바(단, 가능하면 헤테로사이클릭 그룹으로 치환된 알케닐, 및 치환된 헤테로사이클릭 그룹으로 치환된 알킬은 제의함)와 같고: R₂가 -COO-(아릴), -COO-(아르알킬), 또는 바람직하게는 -COON- 또는 -COO-(저급알킬)이며: R₃가 수소 또는 저급알킬이고: R₄가 바람직하게는 본 그룹의 화합물에서 R1에 대해 상기 정의된 그룹중 하나이거나,

(여기에서, n은 0 또는 1내지 8이며, m은 2 내지 8이다), 아다만틸 또는 인돌릴이며: R₅가 수소이고: R₆가 바람직하게는 본 그룹의 화합물에서, R₄에 대해 상기 정의된 그룹중 하나이며, R₉가 바람직하게는 카복실인 화합물 부류이다.Another important subclass of compounds of the invention is that X is

And y is preferably 0 and R ₁ is as defined above for Formula (I), provided that alkenyl is substituted with a heterocyclic group if possible, and alkyl substituted with a substituted heterocyclic group Is the same as: R ₂ is -COO- (aryl), -COO- (aralkyl), or preferably -COON- or -COO- (lower alkyl): R ₃ is hydrogen or lower alkyl R ₄ is preferably one of the groups defined above for R 1 in the compounds of this group,

And (wherein, n is 0 or 1 to 8, m is from 2 to 8, a), adamantyl or indolyl: R ₅ is hydrogen: in the compounds of the R ₆ preferably a group, R ₄ One of the groups defined above for R ₉ is preferably a class of compounds in which R ₉ is preferably carboxyl.

이고, y가 바람직하게는 0이며, R₁이 일반식(I)에 대해 상기 정의된 바(단, 가능하면 헤테로사이클릭 그룹으로 치환된 알케닐, 및 치환된 헤테로사이클릭 그룹으로 치환된 알킬은 제외함)와 같고: X가

이며: R₃, R₄, R₆, R₁₀및 R₁₁이 일반식(I)에 대해 상기 정의된 바와 같고: R₅가 수소이며: R₉가 카복실이고, R₄가 수소, 아릴 또는 헤테로아릴인 경우에 X는 바람직하게는

인 화합물 부류이다.Another important sub-class of the compounds of the invention is that R ₂ is

And y is preferably 0 and R ₁ is as defined above for Formula (I), provided that alkenyl is substituted with a heterocyclic group if possible, and alkyl substituted with a substituted heterocyclic group ), Where X is

R ₃ , R ₄ , R ₆ , R ₁₀ and R ₁₁ are as defined above for Formula (I): R ₅ is hydrogen: R ₉ is carboxyl and R ₄ is hydrogen, aryl or hetero X in the case of aryl is preferably

Phosphorus compound class.

1) The terms alkyl, alkoxy and alkenyl refer to a group having 1 to 20 carbon atoms, where a straight or branched group and / or a group of one or more cycloaliphatic rings is included: 2) lower alkyl, lower The term alkoxy and lower alkenyl refers to a group having from 1 to 8 carbon atoms: 3) The term aralkyl refers to a group having from 7 to 20 carbon atoms and the alkyl moiety is straight or branched and / or comprises one or more alicyclic rings. Group: 4) heterocyclic-, including a 4, 5 or 6 membered ring, wherein two of the members may be heteroatoms, one being nitrogen and the other being oxygen or sulfur 5) Heteroaryl- includes a 5 or 6 membered aromatic ring having 1 or 2 heteroatoms selected from S, N and O: 6) Heteroaralkyl- is heteroaryl as defined above Substituted above 7) Aryl- means a radical derived by removing one hydrogen from an aromatic hydrocarbon, wherein phenyl, tolyl and naphthyl, and substituted phenyl, wherein substituents are preferred Preferably halogen, hydroxy, polyhalo lower alkyl, (e.g. trifluoromethyl), nitro, lower alkoxyamino, lower alkylamino, di-lower alkylamino, acylamino, lower alkyl, lower alkoxy, amino, cya Furnace, and / or sulfonimide).

Representative examples of such novel compounds are as follows: N- (L-1-carboxy-3-phenylpropyl) -L-3- (3-thienyl) alanyl-L-alanine, melting point: 192.5 ° C. to 193 ° C. : N- (D, L-1-carboxy-3-phenylpropyl) -L-3 (2-naphthyl) alanyl-L-alanine, melting point: 149 ° C to 155 ° C: N- (L-1- Oxycarbonyl-3-phenylpropyl) -L-3- (2'-thienyl) -alanyl-L-alanine, or its maleate salt, melting point: 124 ° C to 124.5 ° C (100 to 110 ° C): N -(D-1-carboxy-3-phenylpropyl) -L- (4-fluorophenyl) alanyl-L-alanine, melting point: 147 ° C to 152 ° C: N- (L-1-carboxy-3-phenyl Propyl) -L-3- (1-naphthyl) alanyl-β-alanine: N- (D-1-carboxy-3-phenylpropyl) -L-3- (3-thienyl) alanyl-L- Alanine, melting point: 163 ° C to 164 ° C: N (L-carboxy-3-phenylpropyl) -L-3- (1-naphthyl) alanyl-L-alanine, melting point: 155 ° C to 156 ° C: N- ( 1-carboxy-3-phenylpropyl) -L-3- (3-thienyl) alanyl-L-alanine and its monoethanolate, melting point: 163 ° C to 164 ° C: N- (L-1-ka Cy-2-benzylthio) ethyl) -phenyl alanyl- (L) -alanine and its sesquihydrate, melting point: 153 ° C to 154 ° C: N- (L-1-carboxy-2- (benzylthio)- Ethyl) -L-phenalalanyl-β-alanine: N- (L-1-carboxy-2-phenatyl) -L-phenylalanyl-γ-aminobutyric acid, melting point: 209 ° C to 211 ° C (179 to 181 ° C) C): N- (L-1-carboxy-3-phenylpropyl) -L-phenylalanyl-β-alanine (melting point 189-191 ° C) or hemihydrate thereof (melting point: 176 ° C to 190 ° C): N- (L-1-carboxy-3-phenylpropyl) -D, L-3- (1-naphthyl) alanyl-L-alanine, melting point: 186 ° C to 194 ° C: (D) -N- (1-to Oxycarbonyl-3-phenylpropyl) -phenylalanyl-β-alanine (melting point: 101-103 ° C) or its maleate salt (melting point: 94-97 ° C):

(D) -N- (1-carboxy-3-phenylpropyl) -phenylalanyl-β-alanine, melting point: 183 to 185 ° C (190 to 192 ° C): NL- (1-carboxy-3-phenylpropyl) -L-3- (2-naphthyl) alanyl-L-alanine, melting point: 149-155 ° C: N-[(L) -1-carboxy-2- (1-naphthyl) ethyl]-(L) -(4-phenyl-2-aminobutyloyl) -β-alanine, melting point: 206 to 207 ° C: N- (L)-(1-carboxy-2-phenylethyl)-(L) -homophenylalanyl -β-alanine, melting point: 200 to 201 ° C: N- (L)-(1-ethoxycarbonyl-3-phenylpropyl)-(D) -phenylalanyl-β-alanine, melting point: 103 to 105 ° C :

N- (L)-(1-carboxy-2-phenylethyl)-(L) -phenylalanyl-β-alanine-2-phenethylamide, melting point: 204-205 ° C: N- (L)-(1 -Benzyloxycarbonyl-2-phenylethyl)-(L) -phenylalanyl-β-alanine, benzyl ester: N- (L)-(1-benzyloxycarbonyl) -2-phenylethyl)-(L ) -Phenylalanyl-β-alanine- (2-methyl-3-trifluoromethyl) -anilide, melting point: 114 to 116 ° C: N-[(D, L) -1-carboxy-2-phenylethyl ] -L-Loisyl- (L) -phenylalanine or hemihydrate thereof, Melting point: 178 to 180 ° C: N-[(L) -1-carboxy-2-phenylethyl)]-(L) -loisyl-β Alanine true fluoroacetate, melting point: 70-72 ° C .: N- (L)-(1-carboxy-2-phenylethyl)-(L) -phenylalanyl-β-alanyl- (2-methyl-3 -Trifluoromethyl) -anilide, melting point: 191 to 192 ° C: N- (L)-(1-benzyloxycarbonyl-2-phenylethyl)-(L) -phenylalanyl-β-alanyl mor Pauline amide: N-[(L) -1-carboxy-2-phenylethyl]-(L) -phenylalanyl-β-alanyl morpholine amide, Melting point: 127- 129 ° C: N- (L-1-ethoxycarbonylethyl) -L-2-thienyl-alanylglycine: N- (L-1-ethoxycarbonylethyl) -L-2-thienylalanyl -L-alanine: N- (L-1-ethoxycarbonylethyl) -L-3-thienylalanyl-L-alanine: N- (L-1-ethoxycarbonylethyl) -L-3- Thienylalanylglycine: N- (L-1-carboxyethyl) -L-3-thienylalanyl-L-alanine: N- (L-1-tert-butoxycarbonylethyl) -L-2 Thienylalanyl-L-alanine: N-[(R) -1-benzyloxycarbonyl-2-phenylethyl]-(R) -phenylalanine-β-alanyl-2, 2-dimethylpropionyloxymethyl Ester: N- [1-carboxy-2- (1-naphthylethyl)]-(R) -phenylalanyl-β-alanine, melting point: 183 to 187 ° C: N- (S)-(1-carboxy- 2-phenylethyl)-(S) -paraphenylalanyl-β-alanine: N- (L) -1-carboxy-2-paramethyl-phenylethyl (L) -phenylalanine-β-alanine, melting point: 222 to 224 ° C .: and pharmaceutically acceptable salts thereof.

이고, R₂가 카복시 또는 -COO(저급알킬)이며, R₅가 수소이고, R₉가 카복실이며, y가 바람직하게는 0인 일반식(I)의 화합물 중에서, 중요한 화합물의 예로는, R₁및 R₃가 둘다 수소이고, R₂가 -COO (저급알킬), 예를들면 -COOC₂H₅인 화합물: R₁이 수소,알킬 또는 아르알킬이고, R₄가 3-인돌릴, 알킬 또는 헤테로아릴이며, R₆가 수소 또는 저급알킬이고, R₃가 수소 또는 저급알킬인 화합물: R₁이 아르알킬, 예를들면 C₆H₅-(CH₂)₂-이고, R₂가 카복시이며, R₄가 아릴, 예를들면 페닐이고, R₃및 R₆가 둘다 수소인 화합물: R₁이 알킬, 예를들면 메틸이고, R₂가 카복시이며, R₃가 수소이고, R₄가 헤테로아릴, 예를들면 4-이미다졸릴이며, R₆가 저급알킬, 예를들면 메틸인 화합물: R₁이 메틸, 펜에틸 또는 아르알킬 티오알킬이고, R₂가 -COOH이며, R₄가 페닐이고, R₆가 수소, 메틸 또는 이소부틸인 화합물: 및 R₁이 펜에틸 또는 메틸이고, R₂가 -COO- (저급알킬)이며, R₃가 수소이고, R₄가 3-인돌릴, 헤테로 아릴 또는 아릴이며, R₆가 수소 또는 저급알킬인 화합물이다.X

Among the compounds of the general formula (I) wherein R ₂ is carboxy or -COO (lower alkyl), R ₅ is hydrogen, R ₉ is carboxyl, and y is preferably 0, examples of important compounds are R ₁ and R ₃ are both hydrogen and R ₂ is —COO (lower alkyl), for example —COOC ₂ H ₅ : R ₁ is hydrogen, alkyl or aralkyl, R ₄ is 3-indolyl, alkyl Or heteroaryl, R ₆ is hydrogen or lower alkyl, R ₃ is hydrogen or lower alkyl: R ₁ is aralkyl, for example C ₆ H _5- (CH ₂ ) _2- , R ₂ is carboxy R ₄ is aryl, for example phenyl, and R ₃ and R ₆ are both hydrogen: R ₁ is alkyl, for example methyl, R ₂ is carboxy, R ₃ is hydrogen, R ₄ is Heteroaryl, for example 4-imidazolyl, R ₆ is loweralkyl, for example methyl: R ₁ is methyl, phenethyl or aralkyl thioalkyl, R ₂ is -COOH, R ₄ is Phenyl , R ₆ is hydrogen, methyl or isobutyl in the compound: and and R ₁ is phenethyl or methyl, and R ₂ is -COO- (lower alkyl), and R ₃ is hydrogen, R ₄ is 3-indolyl, heteroaryl, Aryl or aryl and R ₆ is hydrogen or lower alkyl.

이고, R₉가 카복실이며 y가 바람직하게는 O인 일반식(I)의 화합물 중에서, X가

인 경우 일반적으로 중요한 화합물은, R₁이 수소, 알킬, 아릴 또는 아르알킬이고, R₄가 저급알킬, 아릴, 아르알킬 (예:벤질), 헤테로 알킬 또는 헤테로아릴인 화합물, 예를들면 R₁이 메틸 또는 펜에틸이고, R₃및 R₅가 수소이며, R₆가 수소 또는 저급알킬 (예; 메틸)이고, R₁₀이 수소이며, R₁₁이 하이드록시 또는 메톡시인 화합물이며; X가

인 경우 일반적으로 중요한 화합물은, R₁이 수소, 알킬, 아릴 및 아르알킬이고, R₄가 저급알킬, 아르알킬 (예:벤질) 또는 헤테로아르알킬인 화합물, 예를들면 R₁이 메틸 또는 펜에틸이고, R₃, R₅및 R₆가 수소 또는 저급알킬 (예: 메틸)이며, R₁₀이 수소이고, R₁₁이 하이드록시 또는 메톡시인 화합물이다.Typical yeryo of the compound is a compound having the following substituent combinations (i) and (ii): (i) R 1 = _{hydrogen, R 2 = -COOC 2 H 5} , R 3 = H, R 4 -3- indolyl , R ₆ = H, and (ii) R ₁ = methyl, R ₂ = -COOH, R ₃ = H, R ₄ = 4-imidazolyl, R ₆ = methyl, R ₂ is

In the compound of formula (I) wherein R ₉ is carboxyl and y is preferably O, X is

In general, compounds of interest are those compounds in which R ₁ is hydrogen, alkyl, aryl or aralkyl and R ₄ is loweralkyl, aryl, aralkyl (eg benzyl), heteroalkyl or heteroaryl, for example R ₁ Is methyl or phenethyl, R ₃ and R ₅ are hydrogen, R ₆ is hydrogen or lower alkyl (eg methyl), R ₁₀ is hydrogen, and R ₁₁ is hydroxy or methoxy; X

Generally important compounds when are compounds wherein R ₁ is hydrogen, alkyl, aryl and aralkyl, and R ₄ is lower alkyl, aralkyl (eg benzyl) or heteroaralkyl, for example R ₁ is methyl or pen Ethyl, R ₃ , R ₅ and R ₆ are hydrogen or lower alkyl (eg methyl), R ₁₀ is hydrogen and R ₁₁ is hydroxy or methoxy.

인 화합물이다.Another compound of particular interest is R ₁ substituted benzyl or phenethyl, R ₄ is naphthylmethyl or naphthylmethyl or benzyl or substituted benzyl and R ₃ , R ₆ , R ₇ , R ₈ , R ₁₀ Is hydrogen, R ₉ is carboxyl, R ₁₁ is methyl, y is 1 and X is

Phosphorus compound.

Compounds defined above for Formula (I), including compounds excluded by conditions, have been found to be useful for inhibiting enkephalinase, as described below in vivo and in vitro tests. In addition to the above-described compounds representative of such compounds are as follows:

N- (L-1-carboxy-3-phenylpropyl) -L-phenylalanyl-L-alanine: N- (D, L-1-carboxy-ethyl) -L-phenylalanine-L-alanine: N- ( D, L-carboxy-3-phenylpropyl) -L-phenyl-alanyl glycine: N- (L-carboxy-3-phenylpropyl) -L-phenyl-alanyl-L-alanine: N- (L-1 -Carboxy-2-methyl propyl) -D, L-phenyl-alanine-L-alanine: N- (L-1-ethoxycarbonyl-3-phenylpropyl) -D-phenylalanine-L-alanine: N- ( L) -1-Carboxy-2-phenylethyl) -L-Roylsil-L-phenylalanine: N- (1-carboxy-3-phenylpropyl) -L-phenylalanyl-L-alanine 1/2 isopropanol, melting point : 164-164.5 degreeC: N- (D-1-carboxy-3-phenylpropyl) -L-phenylalanyl-L-alanine, melting | fusing point: 214-215 degreeC: N- (L-1-ethoxycarbonyl- 3-phenylpropyl) -L-phenylalanyl-L-alanine or maleate thereof, melting point: 128 to 130 ° C (115 to 120 ° C): N- (1-carboxy-3-phenylpropyl) -L-phenylala Nyl-glycine hemihydrate, melting point: 140 to 145 ° C: N- (1-carboxy-1-methyl) -L-phenylalanylglycid and Ha of deureyiteu, melting point: 125 to 132 ℃: and pharmaceutically acceptable salts thereof.

이 아닌 화합물을 제조하기 위해서, 다음 일반식(A)화합물(각 반응성 그룹은 반응전에 적절히 보호되어 있다)의 C=N 이중결합을 환원시키고, 필요한 경우, 보호 그룹을 제거하여 다음 일반식(I)의 디펩티드를 생성시키고, 필요한 경우, 수득된 일반식(I) 화합물을 예를들어 R₂및 R₉그룹을 적절하게 전환시킴에 의해 일반식(I)의 다른 화합물로 전환시킨다.The compounds of the present invention can be prepared by the following various methods. a) R ₂

In order to prepare a non-compound compound, the C = N double bond of the following compound of formula (A) (each reactive group is suitably protected before the reaction) is reduced and, if necessary, the protecting group is removed to remove Dipeptide) and, if necessary, the obtained compound of formula (I) is converted to another compound of formula (I), for example by appropriately converting the R ₂ and R ₉ groups.

The process can be carried out by reducing the Schiffbase itself formed in a reaction mixture from keto acids or esterified amino acids or esters according to the following scheme.

이다. 예를들어, 케토산 또는 에스테르와 1급 아민(D)와의 반응은, 거의 중성조건하에 적절한 환원제, 예를들면 나트륨 시아노보로하이드라이드의 존재하에서, 용매로서 예를들어 물 또는 메탄올을 사용하여 수행할 수 있다. 또는, 케토산 또는 에스테르(C)와 아미노산 또는 에스테르(D)와의 반응에 의해 수득된 쉬프염기를 수소 존재하에 1 내지 4기압에서 촉매적으로 환원시킬 수도 있으며: 적절한 촉매로는 라니 니켈 및 탄소상팔라듐(예: 탄소상 10% 팔라듐)이 있다.X in the reductive condensation reaction is preferably

to be. For example, the reaction of a keto acid or ester with a primary amine (D) can be carried out using, for example, water or methanol as a solvent, in the presence of a suitable reducing agent such as sodium cyanoborohydride under near neutral conditions. Can be done. Alternatively, the Schiffbase obtained by the reaction of a keto acid or ester (C) with an amino acid or ester (D) may be catalytically reduced at 1-4 atmospheres in the presence of hydrogen: suitable catalysts include Raney nickel and carbon. Palladium (eg 10% palladium on carbon).

Typically, group R ₉ is a protected carboxyl group (eg benzyloxycarbonyl) or lower alkoxy carbonyl (eg tert-butyloxycarbonyl). In this case, the general formula is that R ₉ is carboxyl by reducing the protecting group by reaction with conventional hydrolysis or hydrolysis, for example by hydrolysis under basic conditions, for example with sodium hydroxide in a suitable solvent. The compound of (I) can be obtained.

그룹 또는 알콕시 그룹으로 전환시킬 수 있다. 예를들면 일반식(I)의 화합물을 socl₂또는 옥살릴 클로라이드와 반응시킴에 의해, R₉그룹을 활성화 에스테르 그룹으로 전환시킨 다음, 아민 HNR₂₀R₂₁또는 알콜과 반응시켜 목적 화합물을 수득할 수 있다.When R ₉ is carboxyl,

Can be converted to a group or an alkoxy group. For example, by reacting a compound of formula (I) with socl ₂ or oxalyl chloride, the R ₉ group is converted to an activated ester group and then reacted with an amine HNR ₂₀ R ₂₁ or an alcohol to give the desired compound. Can be.

인 화합물을 예를 들어 설명한다.Compound (C) can be prepared according to the following scheme. X

A phosphorus compound is demonstrated to an example.

In the above scheme, the amino group of amino acid (F) can be protected with, for example, conventional amino protecting groups (P) (eg benzyloxy carbonyl or tert-butyloxycarbonyl).

A condensing agent such as dicyclohexylcarbodiimide (DCC) or diphenyl phosphoryl azide can be used to condense amino acid (F) with an aminoester derivative (G). An activator such as 1-hydroxybenzodiazole can be used for the condensation reaction.

The amino protecting group (P) attached to the resulting dipeptide (H) is then removed by conventional treatment, for example by treatment with an acid or by hydrogenation with hydrogen in the presence of a metal catalyst.

인 화합물인 경우, 화합물 (A)는 다음 일반식(T)의 염가를 분리한 후, 약산성 조건하에서 환원제(예:시아노보로 하이드라이드)를 사용하여 환원시킬 수 있다):X

In the case of phosphorus compounds, compound (A) can be reduced using a reducing agent (e.g., cyanoborohydride) under mildly acidic conditions after separating the cost of the following general formula (T):

The following general formula produced is then treated with known methods, such as hydrolysis or hydrogenolysis, to form terminal carboxy groups when R ₉ is a protected carboxy group, and likewise a carboxy group in which the R ₂ group is protected If, if necessary, it can be converted to carboxyl.

Starting compounds (T) can be formed by the following reaction scheme:

In the above scheme, the protected-carboxy substituted hydrazine is condensed with an appropriately substituted aldehyde, the resulting compound (L) is isolated, and then the compound (L) is reduced by hydrogenation with hydrogen under a palladium on carbon catalyst, or N-protected hydrazine (M) is prepared by reduction with treatment with a reducing agent such as sodium borohydride.

The resulting hydrazine (M) is then reacted with an appropriately substituted isocyanate (O) to form an N-protected aminopeptide (P). As described in the above scheme, α-amino acid ester hydrochloride (N) may be treated with phosgene in a hydrocarbon solvent, the solvent is removed and the residue is distilled off to yield isocyanate (O).

The protected carboxy group on the terminal amino group of compound (P) is then removed by standard methods, for example by acid hydrolysis using acetic acid or trifluoroacetic acid to give the free amine (R). Can be [Reference: J. chem. Soc. Perkin I.246 (1976), followed by condensation of this free amine (R) with an appropriately substituted acid ketone or aldehyde (S) under basic conditions, for example in the presence of sodium acetate. Let's do it. For example, pyruvic acid ethyl ester as ketone (S) is used to produce hydrazone (T) with R ₁ -CH ₃ and R ₂ -COOC ₂ H ₅ . In the scheme, R ₉ may be, for example, methoxycarbonyl. The resulting compound (T) can then be treated with sodium cyanoborohydride under reduced acid conditions to reduce to produce compound (E).

Alternatively, when the primary amine (R) is condensed with ketone or aldehyde (S) under mildly acidic conditions, for example in the presence of acetic acid, in the presence of a reducing agent (e.g. sodium cyanoborohydride), the hydrazone (T) It can be reduced as it is formed to yield compound (E) directly.

b) The compounds of the present invention also couple an amino acid ester of the general formula (A ') with a compound of the general formula (B') (each reactive group is suitably protected before the reaction), It may be prepared by removing to produce a dipeptide of the following general formula (C ′), and if necessary, converting the obtained compound of general formula (I) to another compound of general formula (I).

이고, R₂가

이 아닌 화합물을 제조하고자 하는 경우, 다음 반응도식에 따라, 적절히 치환된 아미노산을 케토산 또는 에스테르와 환원적으로 축합시켜 화합물(B')를 생성시킬 수 있다.X

R ₂ is

If a non-compound compound is to be prepared, the compound (B ′) can be produced by reducing condensation of an appropriately substituted amino acid with keto acid or ester according to the following scheme.

However, preferably compound (B ') is prepared by reductively condensation of an appropriately substituted ketone acid like an amino acid ester.

These condensation reactions may be carried out under the conditions described above in connection with the reaction of compounds (D) and (C) in process a). The resulting compound (E) is coupled with amino acid (A ′), wherein R ₉ is alkoxycarbonyl or dialkyl aminocarbonyl or other non-reactive group as defined above as R ₉ .

인 화합물에 적합하다. 이러한 화합물을 위한 출발중간체(B')로는 다음 화합물(D')를 예로 들 수 있다.Method b) is R ₂

Suitable for phosphorus compounds. Starting intermediates (B ′) for such compounds include the following compounds (D ′).

CO₁H의 치환된 피루부산과 반응시켜 쉬프염기를 제조하고, 이를 바람직하게는 나트륨 시아노 보로하이드 라이드를 사용하여 환원시킴에 의해 생성시킬 수 있다.Wherein R ₁₀ is alkyl or benzyl. Compound (D ') is a general formula, for example with an amine of general formula (P').

A Schiffbase can be prepared by reacting with substituted pyrubusic acid of CO ₁ H, which is preferably produced by reducing with sodium cyano borohydride.

Examples of compound (A ') reacted with compound (D') in this particular method include appropriately substituted amino acids (ie, R ₉ is -COOMe), and the reaction conditions include, for example, axes such as DCC. Use coalescing

With appropriate selection of the protecting groups for R ₉ and R ₁₀ , the resulting compound is optionally de-protected in a conventional manner in group R _{9 such} that R ₉ is carboxyl and group R ₁₀ is left as necessary to leave the terminal carboxyl group If desired, both R ₉ and —OR ₁₀ may be hydrolyzed under alkaline conditions to produce hydroxy.

Standard methods can be used to couple compound (B ') to amino acid (A'), an example of which involves first reacting compound (B ') with an activator (e.g., 1-hydroxybenzotriazole). To produce an activated ester, which is then reacted with compound (A ') and treated with a condensing agent such as 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride.

인 화합물을 제조하는 또 다른 방법은, 일반식(X)의 화합물(각 반응성 그룹은 반응전에 적절히 보호되어 있다)을 환원시켜 일반식(G')의 화합물을 생성시킨 다음, 보호그룹을 제거하는 방법이다.c) X is

Another method of preparing the phosphorus compound is to reduce the compound of formula (X) (each reactive group is suitably protected before the reaction) to produce a compound of formula (G '), and then remove the protecting group. It is a way.

This method is conveniently carried out by condensing a ketone of general formula (E ′) with an amino acid or ester of general formula (F ′) in the presence of a reducing agent (eg sodium cyanoborohydride).

이 아닌 화합물을 상술한 방법으로 더 처리하여 작용기 R₂및 R₉를 적절히 전환시킴에 의해 일반식(I)의 다른 화합물을 형성시킬 수 있다.If necessary, the resulting compound (G ′) having a terminal carboxy group (R ₉ is —COOH), and preferably R ₂ is

Other compounds of general formula (I) can be formed by further treating the non-compounds with the methods described above to properly convert functional groups R ₂ and R ₉ .

Intermediates (E '), wherein R ₉ is -COOH, can be prepared by the following reaction scheme:

Wherein, R ₄ 'is a methyl group (R ₄ As a result, the group constituting R ₄ groups together with the the produced compound (E) is attached to the peptide chain).

N- acetyl-glycine (H ') for the presence of an acetic anhydride / sodium acetate, R ₄ is appropriately substituted aldehyde (preferably an aryl or heteroaryl or heteroaralkyl aldehyde) and condensed, substituted O jorak tone (J ') Is obtained and reacted with amino acid (A) to produce a substituted N-acetyl dehydro dipeptide, which is converted to the corresponding R ₄ substituted pyruboylamino acid (E') in the presence of aqueous acid. .

Alternatively, the starting compound (E ′) can be prepared by condensing an R ₄ substituted pyruvic acid with an amino acid in the presence of dicyclohexyl carbodiimide (DCC) according to the following reaction scheme and then alkaline degrading the resulting ester. have:

(Wherein R ₆ in compound (M ′) may be carbomethoxy, for example).

Hydrolysis of the ester (N ') yields the free keto acid of formula (O').

인 화합물의 경우에, 방법 C)는 R₁₀이 수소가 아니라, 벤질 또는 저급알킬인 화합물을 사용하여 수행할 수 있다. R₁₀이 벤질인 경우에는, 통상의 방법으로 R₁₀을 환원시키고, R₁₀이 알킬인 경우에는, 통상의 방법으로 염기성 가수분해시켜 R₁₀이 수소인 상응하는 화합물을 쉽게 수득할 수 있다.R ₂

In the case of phosphorus compounds, process C) can be carried out using compounds in which R ₁₀ is not hydrogen but benzyl or lower alkyl. If R ₁₀ is benzyl, then R ₁₀ may be reduced by conventional methods and, if R ₁₀ is alkyl, basic hydrolysis may be readily obtained to obtain corresponding compounds wherein R ₁₀ is hydrogen.

Intermediates which can be used to prepare the compounds according to the invention are represented by the following general formula (P) and can generally be condensed with the general formula (E ') compound in the presence of a reducing agent (e.g. sodium cyanoborohydride). .

Wherein R ₁₀ is not hydrogen, the intermediates mentioned above may be prepared, for example, by reacting R ₁ substituted aldehydes, ammonia with R ₁₁ substituted alkoxy or benzyloxyphosphonic acids or benzyloxyphosphinic acids together. Can be.

d) Another method of preparing the compounds of the present invention is the process of reacting an amino acid or ester of the general formula (S ') with a compound of the general formula (T'), each reactive group being suitably protected before the reaction.

Wherein X and various substituents are as defined above and Hal is halogen, eg chlorine or bromine.

인 경우에, R₉가 카복실이면, R₉그룹을 상기 언급한 방법에 의해 알콕시그룹 또는 -NR₂₀R₂₁그룹으로 전환시킬 수 있다.If necessary, preferably X is

When R ₉ is carboxyl, the R ₉ group can be converted to the alkoxy group or the —NR ₂₀ R ₂₁ group by the above-mentioned method.

The reaction of the alkylating agent (T ') with the intermediate (S') can be carried out under conventional alkylation conditions, preferably in the presence of a base (eg tertiary amine) or an inorganic hydroxide, carbonate or bicarbonate. The reaction is usually carried out in water or an organic solvent such as dimethyl formamide or acetonitrile.

인 화합물의 경우에, R₃가 수소인 화합물은 예를 들어 다음 반응도식에 의해 제조할 수 있다:X

In the case of phosphorus compounds, compounds in which R ₃ is hydrogen can be prepared, for example, by the following scheme:

Hydrolysis of the methylated carboxyl group yields a compound wherein R ₉ is carboxy and R ₂ is -COOH. Hal is preferably chlorine or bromine.

인 본 발명 화합물을 제조하는 또 다른 방법은 포스파이트 에스테르 또는 포스포네이트 에스테르를 화합물(A")와 다음과 같이 반응시키고 이때 다른 반응성그룹은 반응전에 적절히 보호되어 있다), 필요한 경우 보호그룹을 제거하는 방법이다.e) R ₂

Another method for preparing a compound of the present invention is to react a phosphite ester or a phosphonate ester with compound (A ") as follows, wherein the other reactive group is suitably protected before the reaction), if necessary, removing the protecting group That's how.

Wherein R ₁₀ is not hydrogen and R ₉ is a protected carboxy group (eg methoxy).

The resulting compound (B "), it is possible to manufacture the terminal carboxyl group by treatment such that the protection group R ₉ is removed. R ₁₀ group may also, if necessary, can be replaced by hydrogen, for example, R ₉ is Hydrolysis of compound (B "), which is lower alkyloxycarbonyl (e.g., methyloxycarbonyl), under basic conditions affords compounds of the invention wherein R ₁₀ is hydrogen and R ₉ is carboxyl.

인 화합물 및 또한 X가

이고, R₄가 펩티드쇄의 탄소에 직접 결합된 수소, 아릴, 헤테로아릴, 아다만틸 또는 인돌릴인 화합물의 경우에 적합하다.The method e) in particular has X

Phosphorus compounds and also X

And R ₄ is hydrogen, aryl, heteroaryl, adamantyl or indolyl bonded directly to the carbon of the peptide chain.

The present invention includes salts of compounds of formula (I) containing one or more free acids or basic groups with inorganic or organic acids or inorganic or organic bases. Such salts include, for example, alkali metal salts (eg sodium and potassium salts) and salts with organic acids (eg maleic acid) and inorganic acids (eg HCl).

Salts can be removed by known methods, for example, in a solvent or reaction medium (e.g. ethyl acetate) in which the salt is insoluble in the free acid or free base form of the product, or in vacuo or by lyophilization. It can be formed by reacting with at least 1 equivalent of an appropriate base or acid.

Where the reactions described above for the preparation of intermediates or for the preparation of the final object compounds of the invention include processes in which water is produced (e.g. condensation), these reactions are azeotropic with a suitable high boiling point solvent (e.g. It can be distilled off or carried out in the presence of a dehydrating agent (eg molecular sieve).

Various intermediates used to prepare the compounds of the present invention by the aforementioned methods are commercially available from Chemical Dynamics Corporation, or the like, and their preparation methods are described in peptides or general chemical literature, such as the following references [1]. See: J. H. Jones Comprehensive Organic Chemistry, Vol 2. p. 819-823, 1979; references 2 and 29-31, and Tetrahedron Letters No. 4, 1978, p. 375-378].

The aforementioned compounds may have chirality centers on their asymmetric carbon atoms.

In general, the compounds prepared by the methods described above may be diastereomeric mixtures of compounds in the form of 'D' and 'L', respectively, in at least one of the chiral centers described above.

Such diastereomeric mixtures may be separated by methods known in the art. For example, each compound can be separated by physical methods, for example by crystallization or chromatography, or by forming salts of diastereomers and then fractionating crystallization.

The present invention includes all stereoisomeric forms of the aforementioned dipeptide compounds.

Preference is given to compounds having a coordination similar to that of natural L-amino acids. Typically, natural amino acids are defined in the S configuration according to the Cuhn-Ingold Prelog System. However, among the natural amino acids, cysteine has an R configuration.

Dipeptide compounds as defined above inhibit the activity of enkephalinase. Some of these compounds have been found to be effective in inhibiting enkephalinase A derived from the rat strata. In in vitro tests, such compounds reduce the activity of the enzyme by 50% or more when used at concentrations of 10 ⁻⁹ to 10 ⁻⁶ M.

The enkephalinase used in this test is obtained by separating the brains of young male rats of Sprague-Dowley species according to the methods described in the literature. Gorenstein et al. in Life Sciences, Vol. 25, pages 2065-2070, pergamon press (1979).

In this method, the activity of various enkephalin degrading enzymes in the brain is determined by the Gorenstein and Synder method [Life Sciences, Sciences, Vol. 25, pp 2065-2070, 1979. The brains of a young rat of Sprague-Dawley species (excluding the cerebellum) are first homogenized in a 30-fold volume of 500 mM Tris buffer (pH 7.4). The resulting homogenate is centrifuged at 50000xg for 15 minutes, the pellet consisting of the membrane-bound enzyme is resuspended in Tris buffer, washed and centrifuged four times as described above.

Membrane pellets are incubated for 45 minutes at 37 ° C. in the presence of 15 mM volume (based on initial brain weight) 50 mM Tris-1% Triton X-100 buffer (pH 7.4) to dissolve. After centrifugation at 100,000 × g for 60 min to remove unsolubles, the Triton-soluble supernatant is loaded onto a 1.5 × 30 cm DEAE Sephacel column (pre-equilibrated with 50 mM Tris-0.1% Triton, pH 7.4). From the column, material is eluted using a 1 l linear NaCl gradient from 0.0 to 0.4 M and the eluate is collected in 7 ml fractions to assay enkephalinase activity for each. Under these conditions, the enkephalinase "A" active substance (dipeptidyl carboxypeptidase) elutes between 120 and 220 ml, followed by the aminopeptidase active substance (260-400 ml), and finally enkephalinase "B" The active substance (dipeptidyl aminopeptidase) was found to elute between 420 and 450 ml.

In this assay, enkephalinase activity is monitored by radiometry. The substrate is 3H-met-enkephalin (50.1 C; 1 mmol, NEN) diluted with 0.05 mM Tris buffer (pH 7.4) to bring the final reaction mixture concentration to 40 mM. The volume of the total reaction mixture including enzyme and substrate is 250 ml.

Incubation is carried out at 37 ° C. for 90 minutes. To stop the reaction, the test tube is transferred to a boiling bath and held for 15 minutes. A 4 ml aliquot of the reaction mixture was then subjected to the unlabeled-standards of met-enkephalin, tyrosine, tyrosyl-glycine, tyrosyl-glycine-glycine on a Baker-Flex silica gel 1B plate (20 × 20 cm). Spot together and chromatograph together the components in an isopropanol: ethyl acetate: 5% (W / V) acetic acid solvent system (2: 2: 1) from which their meth-enkephalins can be separated. The total deployment time is approximately 17 hours. The TLC tank is filled with nitrogen gas before deployment. After development, the spots are visualized by spraying ninhydrin and these spots are lifted out of the plate and the radioactivity corresponding to each spot is monitored by scintillation counting.

Thus the radioactivity of the spots containing Tyr, TyrGly, TyrGlyGly and undigested met-enkephalin, respectively, is measured.

For each plate, the radioactivity of each spot can be expressed as a percentage of the total radioactivity recovered from the plate.

In order to exclude the spontaneous degradation of met-enkephalin in the absence of enzymes, the percentages of radioactivity of Tyr, TyrGly, TyrGlyGly spots were added to the blank containing no enzyme from the corresponding values obtained for the experimental samples in each test using the enzyme. Subtract the percent pure product for each test.

To compare and evaluate different dipeptides types, the net percent product (P) produced in the presence of each and the net percent (A) of product produced in the tests performed in the absence are substituted into the formula (A-P) / P. As a result, the numerical value is a measure from which the enzyme inhibitory activity of various dipeptides can be compared.

In vitro tests have also been shown to enhance the analgesic effect when such compounds are administered parenterally to rats at a dose of 5-100 mg / kg after cerebral administration of D-Ala-meth-enkephalin amide.

The pharmaceutical compositions may be in the form known in the art, for example tablets, capsules or elixirs for oral administration, and sterile solutions or suspensions for parenteral administration.

Dosage forms are advantageously prepared using, in addition to the active dipeptides, pharmaceutically acceptable carriers or excipients, binders, preservatives, stabilizers and fragrances.

Dosage forms are prepared at 5 to 100 mg / kg doses to facilitate administration of conventional active compounds, which are administered at 3 to 8 hour intervals.

Examples of pharmaceutically acceptable carriers used in the above formulations include sugars such as lactose, sucrose, mannitol and sorbitol; Starches such as corn starch, tapioca starch and potato starch; Cellulose, and cellulose derivatives such as sodium carboxy methyl cellulose, ethyl cellulose and methyl cellulose; Calcium phosphates such as di-calcium phosphate, and tri-calcium phosphate; Sodium sulfate, calcium sulfate, polyvinyl pyrrolidone, polyvinyl alcohol, stearic acid; Alkaline earth metal stearates such as magnesium stearate and calcium stearate; Vegetable oils such as peanut oil, cottonseed oil, sesame oil, olive oil and corn oil; Cationic and anionic surfactants; Ethylene glycol polymers; Beta-cyclodextrin; And aliphatic alcohols and hydrolyzed grain solids.

The following examples are intended to illustrate the present invention.

Example 1

Preparation of L-3- (3'-thienyl) alanyl-L-alanine trifluoro acetate salt

a) N-tri-tert-butyloxycarbonyl-L-3- (3'-thienyl) alanine

2.0 g (11.68 mM) of L-3- (3'-thienyl) alanine (Chemical Dynamics Incorporated) was suspended in 1.6 ml of triethylamine and 2.6 g of di-tert-butyl dicarbonate It is dissolved in a mixture of 22 ml of dimethylformamide (DMF) and 22 ml of methanol (pre-dried on molecular sieve).

The DMF / methanol solution is added to the suspension with stirring, and stirring is continued at ambient temperature for 24 hours. The resulting homogeneous solution is diluted with 330 ml of water and acidified with citric acid. The resulting solution is extracted four times with 80 ml each of ethyl acetate and the extract is washed with water and then brine and dried over magnesium sulfate. Evaporate the solvent to afford 3.2 g of the title product.

b) N-tri-tert-butyloxycarbonyl-L-3- (3'-thienyl) alanyl-L-alanine ethyl ester

3.2 g (11.68 mM) of the title product from step a) were combined with 1.8 g of L-alanine ethyl ester hydrochloride (from Sigma Chemicals) and 3.3 g of hydroxybenzyltriazole and 2.0 ml of dimethylformamide. Suspension is stirred in a mixture of triethylamine at ambient temperature. To the suspension is then added 2.5 g of N- (N, N-dimethyl aminopropyl) -N'-ethyl carbodiimide hydrochloride and 2 ml of triethylamine, followed by stirring the resulting mixture overnight. 300 ml of water is added to the reaction mixture, which is extracted four times with 60 ml of ethyl acetate. The combined extracts are washed twice with 70 ml of 1N sodium bicarbonate, twice with 30 ml of 1N citric acid, twice with 70 ml of water, and once with 70 ml of brine. The resulting extract is dried over magnesium sulfate and the solvent is evaporated to yield 5.1 g of the title product.

c) N-tri-tert-butyloxycarbonyl-L-3- (3'-thienyl) alanyl-L-alanine

4.4 g (11.8 mM) of the title product from step b) are dissolved in 30 ml of methanol. 30 ml of water is added to the solution, followed by 1.1 g of NaOH (14.2 mM) in the form of a 50% (W / V) aqueous solution. The reaction mixture is stirred at ambient temperature and after 1 hour, the sample is thin layer chromatography using methanol, chloroform and acetic acid mixture (5: 95: 0.5 volume ratio) as a mobile phase on silica gel to monitor the presence of starting material. With continued stirring, the reaction mixture is monitored in this manner until the completion of the reaction is recognized by the absence of starting materials. The reaction mixture is then concentrated under reduced pressure and the residue is mixed with 30 ml of water; The resulting aqueous solution is washed twice with 30 ml of methylene chloride and then acidified to give a gum precipitate. The precipitate is extracted with ethyl acetate and the extract is dried over magnesium sulfate and then ethyl acetate is evaporated to yield 5.8 g of the title product.

d) L-3- (3'-thienyl) alanyl-L-alanine trifluoroacetate

c) 5.8 g of the title product from step are dissolved in 15 ml of methylene chloride with stirring. 15 ml of trifluoroacetic acid is added to this solution, and the mixture is stirred at room temperature for 2 hours. The reaction mixture is monitored by thin layer chromatography using a methylene chloride, methanol and acetic acid mixture (95: 5: 0.5 volume ratio) from silica gel to mobile phase. If TLC confirms the absence of starting material, the reaction mixture is concentrated to give a gum residue which is dissolved in benzene and distilled to give a residue which is then redissolved in benzene and Distillation again yields 7 g of the title product.

e) N- (1-carboxy-3-phenylpropyl) -L-3- (3-thienyl) alanyl-L-alanine

1N NaOH was added to an aqueous solution of L-3- (3-thienyl) alanyl-L-alanine trifluoroacetate (4.75 g, 13.4 mmol) and 2-oxo-4-phenylbutyric acid (11.0 g, 56.1 mmol). The pH is adjusted to 6.8, and sodium cyanoborohydride (2.2 g, 34.8 mmol) is added to this solution at once, and the resulting reaction mixture is stirred at room temperature for 64 hours. The pH of the resulting solution is adjusted to 2.9 by addition of 1N HCl. The gum product separated from this solution is washed several times with water. The gum product is dissolved in 20 ml of acetonitrile and the solution is diluted with 10 ml of ether. Cooling separates the solids, which are collected by filtration. The mother liquor is left in the refrigerator for 2 days, whereby a white solid precipitates out: this solid is filtered off, washed with acetonitrile and dried to give N- (L-1) diastereomer of the title compound having a melting point of 192.5 ° C. to 193 ° C. Obtain an isomer.

The first mentioned solid is recrystallized from ethanol to give the N- (D-1) diastereomer having a melting point of 163 ° C to 164 ° C.

[Examples 2 to 7]

In a similar manner to Example 1, using the appropriate starting materials, the following compound and diastereomeric mixtures are prepared: 2) N- (L-1-carboxy-3-phenylpropyl) -L-phenylalanyl- L-alanine, Melting point: 176 ° C to 179 ° C; 3) N- (D, L-1-carboxy-3-phenylpropyl) -L-3- (2'-naphthyl) alanyl-L-alanine, melting point: 149 ° C to 155 ° C; 4) N- (1-ethoxycarbonyl-3-phenylpropyl) -L-3- (2'-thienyl) alanyl-L-alanine maleate, melting point: 124 ° C to 125 ° C; 5) N- (D, L-1-carboxy-ethyl) -L-phenylalanyl-L-alanine, melting point: 125 ° C to 135 ° C; 6) N- (D-1-carboxy-3-phenylpropyl) -L- (4-fluorophenyl) alanyl-L-alanine, melting point: 147 ° C to 152 ° C; 7) N- (D, L-1-carboxy-3-phenylpropyl) -L-phenyl-alanyl-glycine, melting point: 140 ° C to 145 ° C.

Example 8

15 g (0.07 mM) of phenylalanine ethyl ester hydrochloride is dissolved in 400 ml of methanol. 2.4 g (0.105 mM) of sodium phenyl pyruvate and 15 g of 3A molecular sieve (Aldrich Chemical) in powder form are added. While stirring the slurry at ambient temperature, 6.6 g (0.105 mM) sodium cyanoborohydride in 75 ml of methanol is added over 6 hours. The slurry is stirred for 2 days, then filtered and the filtrate is concentrated to give a syrup. 300 ml of 2.5% hydrochloric acid is added to the syrup over 3 hours, and the resulting white crystals are filtered and dried under reduced pressure to the content. Representative samples of the dry product were chromatographed using a chloroform: methanol: concentrated hydrochloric acid mixture (50: 15: 1 by volume) on a thin layer of silica gel to estimate the approximate ratio of diastereomers. The chromatogram shows that the mixture is approximately 50/50 of the diastereomers in which a small amount of 3-phenyl-2-hydroxy propionic acid is present.

Yield: 24 g; Melting point: 119 ° to 130 ° C.

NMR results are consistent with that of the desired product.

Crystallization from 400 ml of ethanol yields 14.7 g of the desired compound (in the form of a diastereomeric mixture) in the form of a large amount of fast isomers (identified by thin layer chromatography).

Melting point: 135 ° to 150 ° C.

200 mg of the enriched diastereomeric mixture was recrystallized from 3 ml of methanol to yield 100 mg of crystals, which were confirmed by TLC to be composed of nearly pure, fast developing isomers.

Melting point: 169 ° to 172 ° C.

14.5 g of the reinforced diastereomeric mixture is recrystallized from 400 ml of methanol, but no crystals are formed. The solution is concentrated to 200 ml, seeded and left to stand. Gelatinous precipitates were formed, which were confirmed by TLC and found to be mostly isomeric mixtures with slow isomers. Yield 70 g. 3.0 g of this product was successively used on two silica gel columns on a Waters Prep 500 unit and solvent-based mixture of chloroform: methanol: ammonium hydroxide (500: 150: 10 volume ratio) at a flow rate of 0.2 l per minute. High performance liquid chromatography. 450 mg of isomer I (see below) are obtained from fractions 8 and 9. From fraction 10 400 mg of material is obtained, which is recrystallized from methanol to give 150 mg of isomer I. From fractions 12-15 1.2 g of pure isomer II (see below) are obtained, and from fraction 11 a mixture of isomers I and II is obtained.

For 3.5 g of the same product as above, HPLC is carried out using the same solvent system and adsorbent in the same manner as above. From fraction 4 400 mg of pure isomer I are obtained and from fraction 5 1.0 g of material is obtained, which is recrystallized from methanol to give 550 mg of almost pure isomer I and from fraction 6 of isomers I and II 0.4 g of a mixture are obtained, from fractions 7 to 1.6 g of pure isomer II.

Isomer (I)

Melting point: 171 ° to 173 ° C.

Mass spectrum M + 1 328

282 (M-COOH)

268 (M-COOH ₃ )

236 (M-91)

constitutional formula

Isomer (II)

Melting point: 149 ° to 151 ° C.

Mass spectrum M + 1 328

282 (M-COOH)

268 (M-COOCH ₃ )

The filtrate obtained by filtration of the gelatinous precipitate was concentrated to 50 ml, and 100 ml of acetonitrile was added thereto while cooling to precipitate 1.0 g of white crystals having a melting point of 167 ° to 170 ° C. Recrystallization of these crystals from methanol yields 0.7 g of white crystals having a melting point of 171 ° to 183 ° C.

L-N-[(1-carboxy-2-phenyl) ethyl] -phenylalanyl-β-alanine methyl ester

1.0 g (3.05 mM) of isomer (I) was dissolved in 20 ml of dimethylformamide, followed by 520 mg (3.4 mM) of 1-hydroxybenzotriazole hydrate (HOBT H ₂ O), followed by 472 mg (3.4 mM). Β-alanine methyl ester hydrochloride, 1.3 ml (equivalent) N-ethylmorpholine (NEM) and 649 mg (3.4 mM) N- (3-dimethylaminopropyl) -N-ethylcarbodiimide hydrochloride ( EDCL). The resulting solution is stirred for 48 hours at room temperature and then poured into 150 ml of ice water with stirring and the aqueous solution is extracted twice with 150 ml of ethyl ether. The ethyl ether layer is washed three times with 100 ml of water, followed by the addition of a few drops of HCl, and finally with water. The ether layer is dried over magnesium carbonate, filtered and the filtrate is concentrated to give a point: 1.1 g of the title product are obtained.

L-N-[(1-carboxy-2-phenyl) ethyl] -phenylalanyl-β-alanine

The gum product from the previous step is dissolved in 20 ml of methanol and 6.6 ml of 1N sodium hydroxide is added dropwise with stirring and external cooling over 10 minutes. This solution is allowed to stand overnight (15-20 hours) at room temperature. When the 5% hydrochloric acid solution is added dropwise until the pH of the solution reaches 2.5 (the solution is kept stirring while dropping), a white solid precipitates slowly. The solution is filtered and the filtrate is dried at 40 ° C. under reduced pressure to yield a dose.

Yield: 900 mg

Melting point: 218 ° to 219 ° C.

Mass spectrum M / e 385 (M + 1)

367 (M + 1-18)

340 (M + 1-COOH)

339 (M-45-COOH)

293 (M-91).

[Examples 9 to 15]

In a similar manner to Example 8, using the appropriate starting materials, the following compound and diastereomeric mixtures are prepared. 9) N- (L-1-carboxy-3-phenylpropyl) -D, L-3- (1-naphthyl) alanyl-L-alanine, Melting point: 186 ° C to 194 ° C; 10) N- (L-1-carboxy-3-phenylpropyl) -L-3- (1-naphthyl) alanyl-β-alanine; 11) N- (L-1-carboxy-3-methylpropyl) -D, L-phenyl-alanyl-L-alanine, Melting Point: 160 ° C to 172 ° C; 12) N- (L-1-carboxy-2- (benzylthio) -ethyl) -L-phenylalanyl-β-alanine, mp: 152 ° C to 154 ° C; 13) N- (L-1-carboxy-3-phenylpropyl) -L-phenylalanyl-L-alanine, 14) N- (L-1-carboxy-2-phenylethyl) -L-phenylalanyl- γ-aminobutyric acid, melting point: 209 ° C to 211 ° C; 15) N- (L-1-carboxy-3-phenylpropyl) -L-phenyl-alanyl-β-alanine hemihydrate, melting point: 176 ° C to 190 ° C.

Example 16

N- (D, L-1-carboxyethyl) -L-phenylalanylglycine

To a solution of 0.6 g (2.5 mmol) L-phenylalanylglycine in 5 ml of 1N NaOH and 20 ml of water, a 0.25 g (2.5 mmol) solution of 2-chloropropionic acid in 5 ml of 1N NaOH was added dropwise over 1 hour ; The temperature of the reaction solution during the dropwise addition is maintained at 80 ℃ to 90 ℃, pH is maintained at 8 to 9. Upon completion of the dropwise addition, the reaction mixture is heated to maintain 80 ° C. to 90 ° C. for 15 minutes, evaporated to dryness under reduced pressure and neutralized with 5% (W / V) aqueous hydrochloric acid. Flash-drying to give a gray solid.

The gray solid was stirred with ether to pour off the supernatant; The solid is stirred with cold ethanol. The undissolved solid is filtered from ethanol solution and evaporated to dryness to give the titled diastereomeric mixture having a melting point of 90 ° C. to 120 ° C.

Example 17

a) Preparation of Butyloxycarbonyl Hydrazine

To a stirred solution of 0.1 ml hydrazine hydrate in 15 ml isopropanol is added dropwise a di-tert-butyl dicarbonate solution in isopropanol (a solution of 0.45 ml dicarbonate in 7 ml propanol). At this time, drop by drop speed every 1 sec. The reaction is stopped after dropwise addition of approximately 6/7 tert-butyl dicarbonate.

The mother liquor is evaporated and the resulting solid is chromatographed on silica gel using a chloroform / methanol (97: 3 volume ratio) mixture as mobile phase.

Fractions 20 to 33 were collected and worked up in a conventional manner to yield 0.105 g of the title product having a melting point of 34 ° C to 35 ° C as a solid.

Recrystallization from ether / petroleum ether yields a solid having a melting point of 36.5 ° C. to 37 ° C.

b) Preparation of N-benzylidene-N-tert-butyloxycarbonylhydrazine

3.47 g of the title product from step a) are dissolved in 30 ml of ethanol with stirring and 2.79 g of benzaldehyde is added. The reaction mixture is heated with stirring in the steam bath for 10 minutes and then cooled in an ice water bath. The resulting reaction mixture is filtered to give the title product (3.50 g).

The mother liquor is evaporated to give a solid which is then washed with hexane and filtered to give 1.56 g of solid.

Two fractions are thin layer chromatographed using chloroform / methanol (volume ratio 97: 3) from the silica gel plate to the mobile phase.

Subsequent testing revealed that the two fractions were about the same product. The total yield is 5.06 g and the melting point is 190 ° C to 194.5 ° C.

c) Preparation of N-benzyl-N-tert-butyloxycarbonyl hydrazine

1 g of the title product from step b) is dissolved in 30 ml of tetrahydrofuran and then hydrogenated for approximately 15 minutes by addition of 0.23 g of 5% palladium on carbon catalyst. The reaction mixture is filtered and the mother liquor is evaporated to yield 0.96 g of the title product.

d) Preparation of L-methyl-2-isocyanate-4-methyl valerate

7 g of L-leucine methyl ester is suspended in 200 ml of toluene previously dried over calcium hydride. The suspension is stirred and the excess phosgene gas is bubbled up. After the solids have dissolved, the temperature of the reaction mixture is raised to reflux for half an hour and maintained at this temperature.

After the heating is stopped, the resulting nitrogen gas is bubbled to remove excess phosgene and the hydrogen chloride reaction product is dissolved in the solution. After this operation, the solution is evaporated and the liquid product is distilled off.

_{^{[α] 26 D = -25.55 ℃}} ( toluene, C = 5.7%) (see Document -22.4 ℃ Annalen 1952, 575, 217 .), boiling point: 71 ℃ to 72 ℃ (45mmHg).

e) N-tert-butyloxycarbonyl-α-azaphenylalanyl-L-leucine methyl ester

2.47 g of benzylhydrazino-tert-butylcarboxylate [product of step (c)] is dissolved in 15 ml of toluene with stirring. 1.90 g of d) product is added to the reaction solution followed by 1.12 g of triethylamine. The resulting reaction mixture is stirred for 16 hours, diluted with 200 ml of ethyl acetate and washed once with 5% (W / V) citric acid aqueous solution, then with brine, and finally with water.

The solution was dried over sodium sulfate, sodium sulfate was filtered off and concentrated to give a residue, which was then chromatographed using a mixture of hexane and chloroform (7/3 volume ratio) as eluent on 75 g silica gel. do.

Work up in conventional manner to afford 3.72 g of the title product.

[α] ²⁶ _D = -7.1 ° (C = 3.29% in chloroform)

f) α-azaphenylalanyl-L-leucine methyl ester

8.0 ml of HCl / CH ₃ COOH anhydrous mixture (volume ratio 1/80) is cooled to 4 ° C. with stirring, to which e) step product is added. Stir at 4 ° C. for 20 minutes and remove the solvent under reduced pressure. The residue is chromatographed on silica gel using chloroform / methanol mixture (98/2 V / V) as eluent. The appropriate fractions representing the corresponding rf values are combined to yield 0.163 g of the title product.

[α] ²⁶ _D = + 1.9 °

Mass spectrum M + 293 (-HCl)

262 (-m-OCH ₃ )

234 (-m-CO ₂ CH ₃ )]

g) N- (D, L-1-ethoxycarbonyl-3-phenylpropyl) -α-azaphenyl alanyl-L-leucine methyl ester

0.151 g (0.458 mmol) of the title product of step f) are dissolved in 3 ml of methanol, to which 83.4 mg of ethyl-4-phenyl-2-oxobutanoate is added with stirring at 60 ° C. The reaction is monitored by thin layer chromatography using a chloroform / acetone mixture (9/1 volume ratio) as eluent on silica gel plates. When the reaction is almost complete, 70 mg of sodium cyanoborohydride and 4 drops of 10% (W / V) acetic acid aqueous solution are added.

The reaction is monitored by thin layer chromatography using a mixture of chloroform and methanol (98/2 volume ratio) as eluent on a silica gel plate. Then 70 mg of sodium cyanoborohydride and 4 drops of acetic acid solution mentioned above are further added.

After the reaction solution is left for 16 hours, the solvent is removed under reduced pressure. 40 ml of ethyl acetate is added to the residue, and the resulting solution is washed once with 20 ml of aqueous sodium chloride and then twice with 20 ml of water. The organic solution is dried over magnesium sulphate, filtered and the solvent is removed under reduced pressure.

The residue (0.277 g) is chromatographed on silica gel using a mixture of hexanes / chloroform (7/3 volume ratio) as the eluent. Appropriate fractions according to thin layer migration are combined to give the title product.

h) N- (D, L-1-carboxy-3-phenylpropyl) -α-azaphenylalanyl-L-leucine

g) 0.428 g (0.265 mmol) of the title compound of step) are dissolved in 10 ml of aqueous acetone (acetone / water, 3/1 volume ratio) and the reaction solution is stirred with 1.06 ml of aqueous sodium hydroxide solution (containing 1.06 mmol of NaOH). Add. The reaction is monitored by thin layer chromatography using chloroform / methanol / ammonium hydroxide (1: 1: 1 volume ratio) as eluent. An additional 0.04 ml of sodium hydroxide solution (containing 0.4 mmol of NaOH) is added and the reaction is continuously monitored until the reaction is almost complete.

10 ml of water is added to the reaction mixture, and extracted twice with 30 ml of ethyl acetate. The extracts are combined, dried and concentrated to give a residue.

The residue is chromatographed on silica gel using the lower phase of a mixture of chloroform / methanol / ammonium hydroxide (2: 1: 1 volume ratio) as the eluent.

Combine the appropriate fractions according to the rf values. The combined fractions are recrystallized from diethyl ether and the mother liquor from the first recrystallization is further concentrated to give a second crystal. The total yield of the title compound is 43 mg.

Example 18

A solution of α-azaphenylalanyl-L-leucine methyl ester (see Example 17) and 1 equivalent (relative to ester) in anhydrous methanol is allowed to stand on a 3A type molecular sieve for 16 hours. To the resulting solution is added 1 equivalent (relative to esters) of ethyl phosphonic acid ethyl ester and traces of sodium methoxide. The reaction solution is then left for 6-8 hours. The molecular sieve material is then filtered off and the filtrate is concentrated under reduced pressure. To the concentrated solution is added 2.1 equivalents (relative to the ester) of sodium hydroxide in the form of a 1N aqueous solution and the mixture is stirred at room temperature for 6 hours. The organic solvent is removed under reduced pressure and the residue is diluted with water. The insoluble material is extracted with ethyl acetate and the aqueous solution is acidified to pH 2.5 by addition of 1N HCl. The resulting precipitate is filtered and dried to afford the title compound diastereomeric mixture.

Example 19

Dissolve (1L) -1-amino ethyl phosphonic acid (see US Pat. No. 4016148) in anhydrous methanol and add an equimolar amount of thionyl chloride to the solution at one time, keeping the solution at 0 ° C. during the addition . After the addition is complete, the resulting solution is allowed to warm to room temperature and left at this temperature for 6-8 hours. The volatiles are removed at room temperature under reduced pressure to afford crude (1-L) -1-amino ethyl phosphonic acid dimethyl ester hydrochloride.

Dimethyl ester and equimolar amounts of sodium phenyl pyruvate are dissolved in methanol, 1N NaOH solution is added to this solution to adjust the pH to 6.5-7, and treated with 50% molar excess of sodium cyanoborohydride. The reaction mixture is stirred for 2 days at room temperature and poured into water. The pH of the resulting aqueous mixture is adjusted to 2-3 and the resulting precipitate is extracted with ethyl acetate. The extract is washed with water and dried. Evaporation of the solvent yields crude mono-acids of the following structure:

The mono-acid is dissolved in dimethylformamide with 1 equivalent (relative to mono-acid) of L-alanine methyl ester hydrochloride and 1 equivalent (relative to mono-acid) N-ethylmorpholine. The resulting mixture is cooled to approximately 0 ° C., to which 1 equivalent (relative to mono-acid) of N- (3-dimethylaminopropyl) -N′-ethylcarbodiimide hydrochloride and 1 equivalent of N-ethylmor Pauline and dimethylformamide are added.

The reaction mixture is warmed to room temperature and stirred overnight. It is poured into water and the precipitated product is extracted with ethyl acetate. The extract is washed with 0.5% (W / V) HCl, followed by saturated sodium bicarbonate solution, dried and evaporated to afford the compound of formula

This product is dissolved in methanol, and 3.1 equivalents of sodium hydroxide is added dropwise to the resulting solution in the form of 1N solution. After stirring at room temperature overnight, the reaction mixture is concentrated under reduced pressure, diluted with water and the pH adjusted to 3-4 with 1N HCl solution.

The precipitated product is filtered off, washed with water and dried to give a diastereomeric mixture of the title compound.

Claims (14)

A method for preparing a compound of formula (I) or a pharmaceutically acceptable salt, characterized by reducing the C = N double bond of the compound of formula (A) and removing the protective group present.

Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino Lower alkyl, acylamino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl, guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl Aralkyl, alkylthio lower alkyl, aralkyloxyalkyl, iralkylthioalkyl or heteroaryloxyalkyl (wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy, amino, aminomethyl, carboxyl, Substituted with cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic The group may be selected from one or more of groups selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkyl amino, di-lower alkylamino, acylamino, halogeno, halogeno lower alkyl, cyano and / or sulfonamino. Substituted); R ₂ is -COOH, -COO- (lower alkyl), -COO- (aryl-lower alkyl), -COO- (aryl),

(Lower alkyl), or

Wherein R ₂₀ and R ₂₁ are the same or different and are selected from hydrogen, lower alkyl, aryl, unsubstituted aryl, aralkyl, and substituted aralkyl, where the substituent is at the aryl moiety, or R ₂₀ and R ₂₁ together form a saturated 5 to 7 membered ring which may contain oxygen as the ring heteroatom; R ₃ is hydrogen; X is

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolyl (eg 3-indolyl), indolylalkyl (eg 3-indolylalkyl), aminomethyl -Phenyl lower alkyl, 3-thianaphthenylmethyl and tetrahydro naphthylmethyl; R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ ; R ₉ is selected from the group defined for R ₂ ; when y is 2 or 3, R ₇ and R ₈ may be present on the same or different carbon atoms; Only X

When y is 0, one or more of the following conditions a), b) and c) is applied, and a) R ₁ is pyridyl, thienyl, furanyl, naphthyl lower alkyl, naphthyl or Aralkylthio; b) R ₄ is furanomethyl, cycloloweralkyl, aryllower alkyl, thienylmethyl, tetrahydronaphthyl-methyl, 1- or 2-naphthylmethyl, 3-thianaphthenyl-methyl, cyclolower alkylmethyl, Lower alkoxy lower alkyl, alkoxy lower alkyl, aryl, substituted aryl, wherein the substituents are halogen, lower alkyl, hydroxyl, lower alkoxy, halolowalkyl, nitro, mono- or di-lower alkylamino and cyano One or more), or an aryl substituent as defined in this condition (except for hydroxyl) one or more arylmethyls substituted at the aryl moiety; (c) R ₆ is acylaminoloweralkyl, mono- or di-loweralkylaminoloweralkyl, or one of the groups mentioned in (b) above for R ₄ , except aryl; However, in general formula (A), the reactive group which exists in R <_1> , R <_2> , R <_4> , R <_5> , R <_6> , R <_7> , R <_8> and R <_9> is protected by a protecting group. A compound of formula (I) or a pharmaceutically acceptable salt thereof

Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino Lower alkyl, acylamino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl, guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl Aralkyl, alkylthio lower alkyl, aralkyloxyalkyl, aralkylthioalkyl or heteroaryloxyalkyl (wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy, amino, aminomethyl, carboxyl, Cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic groups Optionally substituted with one or more groups selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkyl amino, di-lower alkylamino, acylamino, halogeno, halogeno lower alkyl, cyano and / or sulfonamino ); R ₂ is -COOH, -COO- (lower alkyl), -COO- (aryl-lower alkyl), -COO- (aryl),

(Lower alkyl), or

Wherein R ₂₀ and R ₂₁ are the same or different and are selected from hydrogen, lower alkyl, aryl, unsubstituted aryl, aralkyl, and substituted aralkyl, wherein the substituent is at the aryl moiety, or R ₂₀ and R ₂₁ together form a saturated 5 to 7 membered ring which may contain oxygen as the ring heteroatom; Or group

Wherein R ₁₀ is hydrogen, lower alkyl or benzyl and R ₁₁ is hydroxy, alkoxy, benzyloxy, lower alkyl, aryl or benzyl; R ₃ is hydrogen or lower alkyl; X is

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolyl (eg 3-indolyl), indolylalkyl (eg 3-indolylalkyl), aminomethyl- Phenylloweralkyl 3-thianaphthenylmethyl and tetrahydro naphthylmethyl: R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ ; R ₉ is selected from the group defined for R ₂ ; when y is 2 or 3, R ₇ and R ₈ may be present on the same or different carbon atoms; X is

, Y is 0, and R ₂ is

If not, one or more of the following conditions a), b), c) and d) applies: a) R ₁ is pyridyl, thienyl, furanyl, naphthyl lower alkyl, naphthyl or ar Alkylthio: b) R ₃ is lower alkyl: c) R ₄ is furanomethyl, cyclolower alkyl, aryl lower alkyl, thienylmethyl, tetrahydronaphthyl-methyl, 1- or 2-naphthylmethyl, 3-thianaphthenyl-methyl, cyclolower alkylmethyl, lower alkoxy lower alkyl, aralkoxy lower alkyl, aryl, substituted aryl, wherein the substituents are halogen, lower alkyl, hydroxyl, lower alkoxyl, halo lower alkyl, One or more of nitro, mono- or di-lower alkylamino and cyano), or an aryl substituent as defined herein (except for hydroxyl), one or more arylmethyls substituted at the aryl moiety and d) R ₆ is an acylaminolower alkyl, mono- or di-lower alkylamino No lower alkyl, or one of the groups mentioned in (c) above for R ₄ , except aryl. The compound of claim 2 wherein X is

ego; R ₁ is hydrogen, substituted or unsubstituted aryl, hetero aryl, wherein the heteroatom is O, S or N, or substituted or unsubstituted lower alkyl, wherein the substituent of the substituted lower alkyl moiety is halogen , Substituted or unsubstituted aryl, heteroaryl, wherein the heteroatom is O, S or N, substituted or unsubstituted arylthio, amino, lower alkanoyl amino, mono- and di-lower alkylamino, substituted Substituted or unsubstituted aryloxy, and substituted or unsubstituted aralkylthio, wherein the substituent on the substituted aryl group or moiety is halogen, lower alkyl, hydroxyl, lower alkoxyl, polyhalo lower alkyl, nitro, mono Or one or more of di-lower alkylamino and cyano); R ₂

, Carboxyl, -COO-loweralkyl, -COO-aryl, -COO-aralkyl, wherein the aryl moiety of the aryl or aralkyl group may be substituted as in R ₁ ,

[Wherein R ₂₀ and R ₂₁ are the same or different and are hydrogen, lower alkyl, aryl, unsubstituted aryl, where the substituents are as defined in R ₁ , aralkyl, and substituted aralkyl Wherein the substituent is an aryl moiety as defined in R ₁ or R ₂₀ and R ₂₁ together with the nitrogen atom form a saturated 5 to 7 membered ring which may contain oxygen as part of the ring R ₄ is hydrogen, furanomethyl, thienylmethyl, tetrahydro-naphthylmethyl, 1- or 2-naphthylmethyl, 3-thianaphthenylmethyl, lower alkyl, cyclolower alkyl, cyclolower alkylmethyl , Hydroxy lower alkyl, acylamino-lower alkyl, amino-lower alkyl, mono- or di-lower alkylamino-lower alkyl, lower alkoxy lower alkyl, alkoxy lower alkyl, wherein the aryl moiety is defined in R ₁ May be substituted), 3-indolyl lower alkyl, Aralkyl, aryl, substituted aralkyl or substituted aryl, wherein the substituents are as defined as aryl substituents in R ₁ : R ₆ , R ₇ and R ₈ are defined above for R ₄ in this paragraph. And R ₉ is a compound of formula (I) or a pharmaceutically acceptable salt thereof selected from the group defined above for R ₂ in this section. The compound of claim 1, wherein y is 1, 2 or 3, R ₁ is aryl lower alkyl, R ₂ is carboxyl, -COO-lower alkyl, or -COO-aryl lower alkyl, R ₂ is hydrogen, R ₄ is benzyl, 1- or 2-naphthyl methyl, lower alkyl, and substituted or unsubstituted phenyl-lower alkyl, or 2- or 3-ethyl tea ring methyl, R _5, R _6, R ₇ and R ₈ is hydrogen , R ₉ is carboxyl, or

Wherein one of R ₂₀ and R ₂₁ is hydrogen and the other is lower alkyl or together with the nitrogen atom to which they are attached a saturated 5-7 membered ring containing oxygen as ring heteroatom A compound of formula (I) or a pharmaceutically acceptable salt thereof. The general formula (I) according to claim 4, wherein y is 1, R ₁ is 1-naphthylmethyl, paratolylmethyl, benzyl or phenylethyl, R ₂ is carboxy, and R ₄ is paratolylmethyl or benzyl. Of a compound or a pharmaceutically acceptable salt thereof. The compound according to claim 5, wherein (S) -N- (1-carboxy-3-phenyl)-(S) -phenyl-alanyl-β-alanine or (S) -N- (carboxy-2-phenylethyl) -(S) -phenylalanyl-β-alanine. The compound of claim 2, wherein y is 0 and X is

R ₁ , R ₃ and R ₅ are as defined in claim ₂ , R ₂ is -COOH, -COO (loweralkyl), -COO (aryl) or -COO- (aryl-loweralkyl), R ₄ and R ₆ are selected from the group defined for R ₁ or indolyl and R 9 is carboxyl. 8. The compound of claim 7 wherein R ₁ is hydrogen, alkyl, aralkyl or aralkylthioalkyl, R ₃ is hydrogen, R ₄ is 3-indolyl, aryl or heteroaryl, and R ₉ is —COOH or —COO (Lower alkyl). The compound of claim 2, wherein y is as defined in claim 2, R ₁ is as defined in claim 2, and R ₂ is

And R ₃ , R ₄ , R ₅ , R ₆ , R ₁₀ , R ₁₁ , R ₂₀ , R ₂₁ and X are as defined in claim 2 and R ₉ is carboxyl. A compound of formula (A ') is coupled to an amino acid of formula (B') and removes the protecting group present, thereby providing a compound of formula (I) or a pharmaceutically acceptable salt thereof How to manufacture.

Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino Lower alkyl, acyl amino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl, guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl Aralkyl, alkylthio lower alkyl, aralkyloxyalkyl, iralkylthioalkyl or heteroaryloxyalkyl, wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy, amino, aminomethyl, carboxyl, Cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic groups The group may be selected from one or more of groups selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkyl amino, di-lower alkylamino, acylamino, halogeno, halogeno lower alkyl, cyano and / or sulfonamino. Substituted); R ₂ is -COOH, -COO- (lower alkyl), -COO- (aryl-lower alkyl), -COO- (aryl),

(Lower alkyl),

Wherein R ₂₀ and R ₂₁ are the same or different and are selected from hydrogen, lower alkyl, aryl, unsubstituted aryl, aralkyl, and substituted aralkyl, where the substituent is at the aryl moiety, or R ₂₀ and R ₂₁ together form a saturated 5 to 7 membered ring which may contain oxygen as the ring heteroatom] or a group

Wherein R ₁₀ is hydrogen, lower alkyl or benzyl and R ₁₁ is hydroxy, alkoxy, benzyloxy, lower alkyl, aryl or benzyl; R ₃ is hydrogen or lower alkyl; X is

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolyl (eg 3-indoline), indolylalkyl (eg 3-indolylalkyl), aminomethyl- Phenylloweralkyl, 3-thianaphthenylmethyl and tetrahydro naphthylmethyl: R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ ; R ₉ is selected from the group defined for R ₂ ; when y is 2 or 3, R ₇ and R ₈ may be present on the same or different carbon atoms; Only X

, Y is 0, and R ₂ is

If not, one or more of the following conditions a), b), c) and d) is applied and a) R ₁ is pyridyl, thienyl, furanyl, naphthyl lower alkyl, naphthyl or ar Alkylthio: b) R ₃ is lower alkyl: c) R ₄ is furanomethyl, cyclolower alkyl, aryllower alkyl, thienylmethyl, tetrahydronaphthyl-methyl, 1- or 2-naphthylmethyl, 3-thianaphthenyl-methyl, cyclolower alkylmethyl, lower alkoxy lower alkyl, aralkoxy lower alkyl, aryl, substituted aryl, wherein the substituents are halogen, lower alkyl, hydroxyl, lower alkoxyl, halo lower alkyl, One or more of nitro, mono- or di-lower alkylamino and cyano), or aryl substituents defined in this condition (except for hydroxyl) one or more arylmethyl substituted at the aryl moiety and : d) R ₆ is lower alkyl, acylamino, mono- or di-lower alkyl Mino lower alkyl, or R ₄ groups referred to in (c) for a one (where aryl is excluded); Provided that the reactive groups present in R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ , and R ₉ in Formulas (A ') and (B') Protected. A method for preparing a compound of formula (I) or a pharmaceutically acceptable salt, characterized by reducing the C = N double bond of the compound of formula (X) and removing the protective group present.

Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino Lower alkyl, acylamino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl, guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl Aralkyl, alkylthio lower alkyl, aralkyloxyalkyl, iralkylthioalkyl or heteroaryloxyalkyl, wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy, amino, aminomethyl, carboxyl, Cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic groups Optionally substituted with one or more groups selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkyl amino, di-lower alkylamino, acylamino, halogeno, halogeno lower alkyl, cyano and / or sulfonamino ); R ₂ is -COOH, -COO- (lower alkyl), -COO- (aryl-lower alkyl), -COO- (aryl),

(Lower alkyl), or

Wherein R ₂₀ and R ₂₁ are the same or different and are selected from hydrogen, lower alkyl, aryl, unsubstituted aryl, aralkyl, and substituted aralkyl, where the substituent is at the aryl moiety, or R ₂₀ and R ₂₁ together form a saturated 5 to 7 membered ring which may contain oxygen as the ring heteroatom]. Or group

Wherein R ₁₀ is hydrogen, lower alkyl or benzyl and R ₁₁ is hydroxy, alkoxy, benzyloxy, lower alkyl, aryl or benzyl; R ₃ is hydrogen; X is

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolyl (eg 3-indolyl), indolylalkyl (eg 3-indolylalkyl), aminomethyl -Phenyl lower alkyl, 3-thianaphthenylmethyl and tetrahydro naphthylmethyl; R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ ; R ₉ is selected from the group defined for R ₂ ; when y is 2 or 3, R ₇ and R ₈ may be present on the same or different carbon atoms; Only X

, Y is 0, and R ₂ is

If not, one or more of the following conditions a), b) and c) applies, and a) R ₁ is pyridyl, thienyl, furanyl, naphthyl lower alkyl, naphthyl or aralkylthio ; b) R ₄ is furanomethyl, cycloloweralkyl, aryllower alkyl, thienylmethyl, tetrahydronaphthyl-methyl, 1- or 2-naphthylmethyl, 3-thianaphthenyl-methyl, cyclolower alkylmethyl, Lower alkoxy lower alkyl, aralkoxy lower alkyl, aryl, substituted aryl, wherein the substituents are halogen, lower alkyl, hydroxyl, lower alkoxy, halo lower alkyl, nitro, mono- or di-lower alkylamino and cyano One or more), or an aryl substituent as defined in this condition (except for hydroxyl) one or more arylmethyls substituted at the aryl moiety; (c) R ₆ is acylaminoloweralkyl, mono- or di-loweralkylaminoloweralkyl, or one of the groups mentioned in (b) above for R ₄ , except aryl; However, in general formula (A), the reactive group which exists in R <_1> , R <_2> , R <_4> , R <_5> , R <_6> , R <_7> , R <_8> and R <_9> is protected by a protecting group. The amine of formula (S ') is alkylated with a compound of formula (T') and the protective group present is removed, thereby providing a compound of formula (I) or a pharmaceutically acceptable salt thereof How to manufacture.

Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino Lower alkyl, acylamino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl, guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl Aralkyl, alkylthio lower alkyl, aralkyloxyalkyl, iralkylthioalkyl or heteroaryloxyalkyl, wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy, amino, aminomethyl, carboxyl, Cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic groups Optionally substituted with one or more groups selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkyl amino, di-lower alkylamino, acylamino, halogeno, halogeno lower alkyl, cyano and / or sulfonamino ); R ₂ is -COOH, -COO- (lower alkyl), -COO- (aryl-lower alkyl), -COO- (aryl),

(Lower alkyl), or

Wherein R ₂₀ and R ₂₁ are the same or different and are selected from hydrogen, lower alkyl, aryl, unsubstituted aryl, aralkyl, and substituted aralkyl, where the substituent is at the aryl moiety, or R ₂₀ and R ₂₁ together form a saturated 5 to 7 membered ring which may contain oxygen as the ring heteroatom]. Or group

Wherein R ₁₀ is hydrogen, lower alkyl or benzyl and R ₁₁ is hydroxy, alkoxy, benzyloxy, lower alkyl, aryl or benzyl; R ₃ is hydrogen; X is

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolyl (eg 3-indolyl), indolylalkyl (eg 3-indolylalkyl), aminomethyl -Phenyl lower alkyl, 3-thianaphthenylmethyl and tetrahydro naphthylmethyl; R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ ; R ₉ is selected from the group defined for R ₂ ; when y is 2 or 3, R ₇ and R ₈ may be present on the same or different carbon atoms; Only X

, Y is 0, and R ₂ is

If not, one or more of the following conditions a), b) and c) applies, and a) R ₁ is pyridyl, thienyl, furanyl, naphthyl lower alkyl, naphthyl or aralkylthio ; b) R ₃ is lower alkyl; c) R ₄ is furanomethyl, cycloloweralkyl, aryllower alkyl, thienylmethyl, tetrahydronaphthyl-methyl, 1- or 2-naphthylmethyl, 3-thianaphthenyl-methyl, cyclolower alkylmethyl, Lower alkoxy lower alkyl, aralkoxy lower alkyl, aryl, substituted aryl, wherein the substituents are halogen, lower alkyl, hydroxyl, lower alkoxy, halo lower alkyl, nitro, mono- or di-lower alkylamino and cyano One or more), or an aryl substituent as defined in this condition (except for hydroxyl) one or more arylmethyls substituted at the aryl moiety; (d) R ₆ is acylaminolower alkyl, mono- or di-loweralkylaminoloweralkyl, or one of the groups mentioned in (c) above for R ₄ , except aryl; Hal is a halogen, provided that the reactive groups present on R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and R ₉ in formulas (S ′) and (T ′) Is protected by a protection group. Reacting a compound of formula (A ″) with a phosphite ester or phosphonate ester of formula (Z) and removing the protecting group present, wherein the compound of formula (I) Method for preparing an acceptable salt.

Wherein R ₁ is hydrogen, alkyl, halogen-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryloxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino Lower alkyl, acylamino-lower alkyl, diarylamino-lower alkyl, arylamino-lower alkyl, guanidino lower alkyl, heteroaryl, aryl, aralkyl, mercapto-lower alkyl, arylthio-lower alkyl, lower alkyl Aralkyl, alkylthio lower alkyl, aralkyloxyalkyl, iralkylthioalkyl or heteroaryloxyalkyl, wherein the latter three radicals are halogen, lower alkyl, lower alkoxy, hydroxy, amino, aminomethyl, carboxyl, Cyano and / or sulfamoyl), or alkyl substituted with an alkenyl or heterocyclic group substituted with a heterocyclic group, wherein the latter two heterocyclic groups Optionally substituted with one or more groups selected from lower alkyl, hydroxy, lower alkoxy, amino, lower alkyl amino, di-lower alkylamino, acylamino, halogeno, halogeno lower alkyl, cyano and / or sulfonamino ); R ₂ is

Wherein R ₁₀ is hydrogen, lower alkyl or benzyl and R ₁₁ is hydroxy, alkoxy, benzyloxy, lower alkyl, aryl or benzyl; R ₃ is hydrogen; X is

Wherein q is 0 or 1 and R ₄ is a group defined for R ₁ , or indolyl (eg 3-indolyl), indolylalkyl (eg 3-indolylalkyl), aminomethyl-phenyl Lower alkyl, 3-thianaphthenylmethyl and tetrahydro naphthylmethyl; R ₅ is hydrogen or lower alkyl; y is 0, 1, 2 or 3; R ₆ , R ₇ and R ₈ are selected from the group defined for R ₄ ; R ₉ is selected from the group defined for R ₂ ; when y is 2 or 3, R ₇ and R ₈ may be present on the same or different carbon atoms; Provided that the reactive groups present on R ₁ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ and R ₁₁ in formulas (A ″) and (Z) are protected by protecting groups. A pharmaceutical composition comprising a compound of formula (I) as defined in claim 2 or a salt thereof in the form of a mixture with a pharmaceutically acceptable carrier or excipient.