WO2005030707A1

WO2005030707A1 - Reduced hydrazinopeptoids and use thereof in the treatment of cancer

Info

Publication number: WO2005030707A1
Application number: PCT/FR2004/002382
Authority: WO
Inventors: Michèle BAUDY-FLOC'H; Yannick Arlot-Bonnemains; Sandrine Aubin
Original assignee: Centre National De La Recherche Scientifique; Universite De Rennes 1
Priority date: 2003-09-23
Filing date: 2004-09-22
Publication date: 2005-04-07
Also published as: FR2859995A1

Abstract

The invention relates to compounds of general formula (I) wherein Y represents CH2 or CO, n represents a whole number from 1 to 10, with the proviso that when n represents 1, Y represents CH2, and when n is greater than 1, one at least of the Y groups Y in formula (I) represents CH2, R1 and R6 represent H, BOC, or Z, or a group of formula -CH2COR wherein R represents a CH2X group, X represents Cl or Br, R2, R3, R4 and R5, independently represent H, an alkyl group with 1 - 10 carbon atoms, and the use thereof in the production of a medicament used to treat cancer.

Description

REDUCED HYDRAZINOPEPTOIDS AND THEIR USES IN THE TREATMENT OF CANCERS

The present invention relates to new reduced hydrazinopeptoid compounds, their methods of synthesis, and their use in the context of the treatment of tumors.

The cell cycle of most cells makes it possible to increase the size, to double the quantity of DNA, to ensure the distribution of the genetic material in an equitable manner in the daughter cells. The cell cycle is divided into two very distinct periods: the interphase during which DNA replication occurs and mitosis.

The replication and mitosis phases are controlled by protein complexes regulated by their phosphorylation / dephosphorylation state and / or their degradation. Many neurodegenerative and / or cancerous pathologies, associated with the presence of improperly structured proteins (aberration in the secondary and tertiary structure of the molecule) or the presence of proteins not degraded at a stage where it is essential that they either, are currently known.

The ubiquitin / proteasome system plays a major role in intracellular proteolysis, the breakdown of a certain number of proteins associated with the good progress of the cell cycle. Inactivation of the proteasome by specific inhibitors of the active site will make it possible to understand the mechanics of the dysfunction of protein degradation and thus to envisage new classes of anti-tumor molecules.

It has been observed that aldehyde peptides inhibiting calpain and proteasome such as N-acetyl-leucinyl-leucinyl-norleucinal (ALLN), benzyloxycarbonyl leucinyl-leucinyl-leucinal (MG132) and N-acetyl-leucinyl- valinylphenylalaninal (ALVP), but not N-acetyl-leucinyl-leucinyl-methioninal (ALLM), have a synergistic action in the suppression of cell proliferation and the induction of apoptosis in three human tumor cell lines as well as in pulmonary adenocarcinomas, prostate carcinomas, and breast carcinomas (Cusak JC, Liu R, Houston M, Adendroth K, Elliot PJ, Adams J and Baldwin AS Jr

(2001) Cancer Res, 61, 3535-3540; Soligo D, Servida D, Fontanella E, Lamorte G, Caneva L, Fumiatti R, and Lambertenghi Deliliers G (2001) Br J Haematol, 113, 126-135; Sun J, Nam S, Lee CS, Li B, Coppola D, Hamilton AD, Dou QP and Sebti SM (2001) Cancer Res, 61, 1280-1284. The transformed peptides and in particular the pseudopeptides arouse a great interest because they are able to behave like more effective analogues than the peptides themselves whose therapeutic applications are however limited by a significant biodegradability, a weak power of crossing of the physiological barriers and by the lack of selectivity vis-à-vis the target. It is therefore necessary to design more active, more stable and more specific analogs. Pseudopeptides for which the chemical nature of the peptide backbone and of the amide bond (CO-NH) is modified, make it possible to induce a greater bioavailability than that of the mimed peptides while preserving good biological activity. This property of pseudopeptides, is linked in particular to the resistance induced with respect to peptidases, which very quickly degrade any exogenous peptide by cutting the peptide skeleton at the level of the amide bonds, and whose action is then slowed down by the modification of these bonds.

Hydrazinopeptoid compounds are described in particular in international application WO 03/018557.

The present invention follows from the demonstration by the Inventors of the fact that the reduced hydrazinopeptoid compounds of formula (I), described below, have a specific action on cancer cells to induce them to enter into apoptosis according to a mechanism of inhibition of the enzymatic activities inherent in the proteasome.

The subject of the invention is the compounds of general formula (I) below:

in which :

• Y represents CH ₂ , or CO,

• n represents an integer from 1 to 10, in particular n represents 1 or 2, provided that when n represents 1, Y represents CH ₂ , and that when n is greater than 1, at least one of the groups Y in the formula (I) represents CH,

• Ri and R _Ô , independently of each other, represent: o a hydrogen atom, o a group which can be used in the context of the protection of nitrogen atoms in peptide synthesis, such as the group BOC, FMOC or Z, a group of formula -COR, or -CH COR in which R represents:

> a hydrogen atom, provided that when R] is hydrogen, it is in the form of a salt soluble in aqueous solvents, such as a trifluoroacetate salt,> an alkyl group of 1 to 10 carbon atoms, optionally substituted by one or more halogen atoms, such as the R groups representing -CF ₃ or a group -CH ₂ X, X representing a halogen atom such as Cl or Br,

a group —COOR _a in which R _a represents H or an alkyl group, such as a methyl or ethyl group,

> a primary amino group -NH or an amine II ^re or III ^re ,

> an alkoxy group, such as a methoxy group -OMe, or ethoxy group -OEt,

> a phenyl group, a pyridinium group, such as the group of formula

"R, R ₃ , R <j and R ₅ , independently of each other, representing: o a hydrogen atom, o an alkyl group of 1 to 10 carbon atoms, optionally substituted, in particular by one or more halogen atoms or by one or more amino or phenyl groups, such as methyl, butyl, isobutyl, - (CH ₂ ) ₄ NH ₂ , -CH ₂ Ph, - (CH ₂ ) ₄ NHBoc, "or R] in association with R ₂ , or R ₆ in association with R, represent a group of formula

The present invention relates to a pharmaceutical composition comprising, in combination with a pharmaceutically acceptable vehicle, a compound of the following general formula (I):

in which: "Y represents CH ₂ or CO,

"n represents an integer from 1 to 10, in particular n represents 1 or 2, provided that when n represents 1, Y represents CH ₂ , and that when n is greater than 1, at least one of the groups Y in the formula (I) represents CH ₂ ,

¹ Ri and R _ô , independently of each other, represent: o a hydrogen atom, o a group which can be used in the context of the protection of nitrogen atoms in peptide synthesis, such as the group BOC, FMOC or Z, o a group of formula -COR, or -CH ₂ COR in which R represents:

> a hydrogen atom, provided that when Rj is hydrogen, this is present, where appropriate, in the form of a salt soluble in aqueous solvents, such as a trifluoroacetate salt,

> an alkyl group of 1 to 10 carbon atoms, optionally substituted by one or more halogen atoms, such as the groups R representing -CF ₃ or a group -CH ₂ X, X representing a halogen atom such that Cl or Br,

> a group -COOR _a in which R _a represents H or an alkyl group, such as a methyl or ethyl group,> a primary amino group -NH ₂ or an amine II ^re or III ^re ,

> an alkoxy group, such as a methoxy group -OMe, or ethoxy group -OEt,

> a phenyl group, a pyridinium group, such as the group of formula CH r—— N Nf ^NN ! Br ^"

"R ₂ , R ₃ , * and R ₅ , independently of each other, representing: o a hydrogen atom, o an alkyl group of 1 to 10 carbon atoms, optionally substituted, in particular by one or more atoms halogen or by one or more amino or phenyl groups, such as methyl, butyl, isobutyl, - (CH ₂ ) ₄ NH ₂ , -CH ₂ Ph, - (CH ₂ ) ₄ NHBoc,

- (CH ₂ ) ₃ NHC (NH ₂ ) = NH,

"or Ri in combination iation with R, represent a group of formula

The present invention also relates to a pharmaceutical composition as defined above, comprising, in association with a pharmaceutically acceptable vehicle, a compound of general formula (I), in which:

"Ri represents a protective group BOC, or Z, or a group -COCH ₂ X, X representing a halogen atom such as Cl or Br, or Ri represents H, provided that when Ri represents H, the latter occurs optionally in the form of a salt, such as a trifluoroacetate salt of formula

CF ₃ CO ₂ ^" , H ₃ N ⁺ -" R ₂ represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group,

"R ₃ represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group, or R ₃ represents a benzyl group," one of Rj or of R ₅ represents H, while the other represents an alkyl group as defined above, and R ₆ represents H or a protective group BOC or Z,

"n represents 1 or 2," Y is as defined above. An advantageous pharmaceutical composition according to the invention is a pharmaceutical composition as defined above, comprising, in association with a pharmaceutically acceptable vehicle, a compound of general formula (I), in which:

Ri represents a protective group BOC, or Z, or a group -COCH ₂ X, X representing a halogen atom such as Cl or Br, or Ri represents H,

- R ₂ represents H, - R ₃ represents an isobutyl group, or a benzyl group,

- R ₄ represents H, or a methyl or isobutyl group,

- R ₅ represents H, or an isobutyl group,

- R _Ô represents a BOC or Z protective group,

- n represents 1, - Y represents CH ₂ . An advantageous pharmaceutical composition according to the invention is characterized in that the compound of formula (I) is chosen from the compounds of the following formula:

According to an advantageous embodiment, the present invention relates to a pharmaceutical composition as defined above comprising, in association with a pharmaceutically acceptable vehicle, a compound of general formula (I), in which:

- Ri is different from R ₂ ,

- R ₅ is different from R _Ô , and

- the group -N (Rι) (R ₂ ) is different from the group -N (R ₅ ) (Re).

The preferred pharmaceutical compositions of the invention are characterized in that the compound of formula (I) is chosen from the compounds of formula (5a), (5b), (5c), (5d), (5e), (7a) , (8a) and (8b). The present invention also relates to a pharmaceutical composition as defined above, characterized in that it is in a form which can be administered intraperitoneally, in particular at a rate of approximately 5 mg / kg / day. The present invention relates to the use of compounds of formula (I) as defined above, for the preparation of a medicament intended for the treatment of cancers such as cancers of the liver, of the colon, of the breast, of melanomas, by inducing entry into apoptosis of cancer cells.

The present invention also relates to compounds of general formula (I) below:

in which :

"Y represents CH ₂ or CO,

"n represents an integer from 1 to 10, in particular n represents 1 or 2, provided that when n represents 1, Y represents CH ₂ , and that when n is greater than 1, at least one of the groups Y in the formula (I) represents CH ₂ , "Ri and R _ό , independently of one another, represent: o a hydrogen atom, o a group which can be used in the context of the protection of nitrogen atoms in peptide synthesis , such as the group BOC, FMOC or Z, o a group of formula -COR, or -CH ₂ COR in which R represents: a hydrogen atom, with the proviso that when Ri is hydrogen, the latter occurs optionally in the form of a salt soluble in aqueous solvents, such as a trifluoroacetate salt, an alkyl group of 1 to 10 carbon atoms, optionally substituted by one or more halogen atoms, such as the groups R representing -CF ₃ or a group -CH X, X representing a halogen atom such as Cl or Br,

a group —COOR _a in which R _a represents H or an alkyl group, such as a methyl or ethyl group, a primary amino group -NH ₂ or an amine II ^re or III ^re , > an alkoxy group, such as a methoxy group -OMe, or ethoxy group -OEt,

> a phenyl group,

> a pyridinium group, such as the group of formula - CH - N y Br ^"

"R ₂ , R ₃ , _t and R ₅ , independently of each other, representing: o a hydrogen atom, o an alkyl group of 1 to 10 carbon atoms, optionally substituted, in particular by one or more atoms halogen or by one or more amino or phenyl groups, such as methyl, butyl, isobutyl, - (CH ₂ ) ₄ NH ₂ , -CH ₂ Ph, - (CH ₂ ) ₄ NHBoc, - (CH ₂ ) ₃ NHC (NH ₂ ) = NH, "or R] in association with R ₂ , or R ₆ in association with R ₅ , represent a group of formula

excluding the compounds corresponding to the following formulas (II), (III), (IN) and

R ′ representing a hydrogen atom, an ethyl group, an isopropyl group, an n-butyl group, an n-propyl group or a group -CH (Me) (Et),

R "representing a hydrogen atom, an ethyl group, an n-butyl group, an n-propyl group or a group -CH ₂ φ,

A representing a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a C5H ₁₁ group or a group

B representing a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a C ₅ H _{1 1} group or a C ₆ Hι _{3 group} . A more particular subject of the invention is the above-mentioned compounds of general formula (I) in which:

"Ri represents a protective group BOC, or Z, or a group -COCH ₂ X, X representing a halogen atom such as Cl or Br, or Ri represents H, provided that when Ri represents H, the latter occurs where appropriate in the form of a salt, such as a trifluoroacetate salt of formula CF ₃ CO ₂ ^" , H ₃ N ⁺ -

"R represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group," R represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group, or R ₃ represents a benzyl group, "one of R ₄ or R ₅ represents H, while the other represents an alkyl group as defined above, and R ₆ represents H or a protective group BOC or Z," n represents 1 or 2, "Y is as defined above. The invention more particularly still relates to the above-mentioned compounds of general formula (I) in which:

"Ri represents a protective group BOC, or Z, or a group -COCH ₂ X, X representing a halogen atom such as Cl or Br, or Rj represents H, R ₂ represents H," R ₃ represents an isobutyl group, or a benzyl group,

R ₄ represents H, or a methyl or isobutyl group, R ₅ represents H, or an isobutyl group, R ₆ represents a BOC or Z protective group, n represents 1, "Y represents CH _2. Compounds which are particularly preferred in the context of the present invention are those of the following formulas:

The preferred compounds according to the invention are compounds of general formula (I), in which:

- Ri is different from R ₂ ,

- R ₅ is different from R ₆ , and

- The group -N (Rι) (R ₂ ) is different from the group -N (R ₅ ) (R _ô ).

Such compounds are in particular chosen from the compounds of formulas (5a), (5b), (5c), (5d), (5e), (7a), (8a) and (8b) mentioned above.

The invention also relates to any pharmaceutical composition comprising a above-mentioned compound of formula (I) in association with a pharmaceutically acceptable vehicle. Advantageously, the pharmaceutical compositions of the invention are characterized in that they are in a form which can be administered intraperitoneally, in particular at a rate of approximately 5 mg / kg / day.

A subject of the invention is also the use of the above-mentioned compounds of formula (I), for the preparation of a medicament intended for the treatment of cancers such as cancers of the liver, of the colon, of the breast, of melanomas, by inducing entry into apoptosis of cancer cells.

The invention also relates to a process for the preparation of an above-mentioned compound of formula (I), characterized in that it comprises the following stages: - reaction of the compound of formula (1) below

R3 in which Ri, R ₂ , and R ₃ are as defined above, with methyl bromoacetate Br '^ ^{^} ^ V'' ^S

O which leads to obtaining the aza-β ³ -amino esters of formula (2) below

N _^ - _"" - ^ ^ -OMe (2)

R, O

in which Ri, R ₂ , and R ₃ are as defined above,

treatment of the compound of formula (2) obtained in the previous step with NaBH and LiCl, which leads to the production of the aza-β ³ -amino alcohols of formula (3) below

in which Ri, R ₂ , and R ₃ are as defined above, - treatment of the compound of formula (3) obtained in the previous step with triethylamine, DMSO, and the oxidizing agent pyridine sulfide trioxide, which leads to the production of aza-β ³ -amino aldehydes of formula (4 ) next

R, - ^N - N ^ - ^H (4)

R ₃ O in which Ri, R ₂ , and R ₃ are as defined above,

- reaction of the compound of formula (4) obtained in the previous step with the compound of formula (Ibis) below

^R 5 in which i, R ₅ , and R ^ are as defined above, which leads to obtaining compounds of formula (5) below

in which Ri, R ₂ , R ₃ R _f , R ₅ , and R _Ô are as defined above,

- If necessary, treatment of the compound of formula (5) obtained in the previous step with trifluoroacetic acid, which leads to the obtaining of compounds of formula (6) below

in which R ₃ R ₄ , R ₅ , and R ₆ are as defined above,

- If necessary, reaction of the compound of formula (6) obtained in the previous step with a compound of formula X-CH ₂ -CO-X in which X represents a halogen atom such as Cl or Br, which leads obtaining compounds of formula (7) according to H

in which X, R ₃ ), R ₅ , and R _Ô are as defined above, - if necessary, reaction of the compound of formula (6) obtained in the previous step with a borylated aldehyde of formula

which leads to obtaining compounds of formula (8) below

wherein R ₃ R ₄ , R ₅ , and R ₆ are as defined above.

A subject of the invention is also the intermediate synthetic compounds corresponding to the formulas (2), (3), and (4) mentioned above, and their use in the context of the implementation in the preparation process described above.

The invention will be further illustrated in the detailed description which follows the synthesis of compounds of the invention, and the study of their biological properties. ALLN (inhibitor of cysteine proteases and proteasome) has a terminal aminoaldehyde C as an electrophilic group. Other inhibitors of comparable activities have been developed, such as the dipeptide Z-Leu-Norleu-H also shown in the diagram below.

Ac-Leu Leu Norleu-H

ALLN Ki = 0.19μM Ki = 0.07μM

ALLN (N-acetyl-Leucyl-Leucyl-Norleucinal) inhibits cell cycle progression by affecting the Gl / S transition and the metaphase-anaphase transition at the time of mitosis. High concentrations of ALLN (> 50 μg / ml) produce a prolonged arrest in mitosis while lower concentrations result in a slowing down of mitosis. The cells can then start a second cycle.

However, it is well known that amino aldehydes are not very stable and racemize very quickly, which leads to a modification or loss of activity. From where the idea of synthesizing analogs having no center of asymmetry of fixed configuration in order to obtain a maximum activity with respect to the specific inhibition of the degradation of the protein kinases involved in the cycle.

The invention converges the development of a new series of pseudopeptides, reduced hydrazinopeptoids of general formula I, and the analysis of their mode of action on biological targets (inhibition of the proteolytic activity of the proteasome in vitro) as well that dysfunctions of cell division observed in certain cancerous or neurodegenerative pathologies.

The cell cycle is divided into two distinct periods: interphase (DNA replication) and mitosis. The transitions between the phases of the eukaryotic cell cycle, and the progression within each of these phases are very strongly controlled at the molecular level. Little is known about the mechanisms that control the entry and exit of mitosis and therefore chromosomal segregation. A defect in one of the stages of these processes can lead to karyotype alterations such as the loss or gain of a chromosome and / or a change in ploidy which are frequently observed in tumors.

Generally, the phases are controlled by protein complexes composed of a catalytic subunit, a protein kinase of the cdk type (cyclin depend kinase) and of a regulatory subunit which is a cyclin. The interdependence between phases S and M requires different levels of regulation. The ubiquitin / proteasome system, which represents one of the mechanisms of protein degradation, intervenes in certain cellular processes, such as the immune response of lymphocytes infested by a virus. It is also involved in the degradation of proteins associated with the smooth running of the cell cycle. The dysfunction of the degradation processes is correlated with a certain number of pathologies such as neurodegenerative or cancerous pathologies. The inactivation of the proteasome by specific inhibitors will make it possible to understand the mechanics of the dysfunction of protein degradation and thus to envisage new classes of antitumor molecules. The ubiquitin / proteasome system is responsible for the breakdown of a large majority of cellular proteins including not only short-lived regulatory proteins (cyclins, cyclin inhibitors, certain protein kinases) but also, improperly structured proteins and / or long half-life. In cancer cells, ubiquitination is sometimes considerably increased which promotes and amplifies the recognition of these by the proteasome as a consequence, this post-translational modification increases the turnover of cycle regulatory proteins and thus contributes to a deregulation of the cell cycle and the appearance of abnormal mitoses. On the other hand, the proteasome is involved in the degradation of proapoptotic proteins, under normal conditions of growth, these proteins are degraded and synthesized at each cycle. A large number of neurodegenerative and / or cancerous pathologies associated with these dysfunctions have been widely documented in recent years. For example, the oncosuppressive function of p53 (protein involved in DNA repair) is impaired in certain cancers such as cervical and colon cancers.

In a normal cell, proteasome inhibitors are relatively inactive. In contrast, proteasome inhibitors are more active on tumor cells inducing the production of apoptotic proteins and consequently the entry of tumor cells into apoptosis. In the syntheses carried out within the framework of the present invention, it is the inhibition of the proteasome that we have targeted in order to produce antimitotic molecules and, in the longer term, envisage new classes of molecules for therapeutic purposes.

Methodology for synthesizing reduced hydrazinopeptoids:

The invention relates to the synthesis of reduced hydrazinopeptoids. The side chains of the monomers, mimicking the amino acids, are carried by nitrogen atoms which are isoelectronic of the CHαs which would give them great conformational freedom. In addition, these monomers have no center of asymmetry of fixed configuration. The correct positioning of the peptide chain in an enzymatic site would occur at the same time by the displacement of conformational and configurational equilibria. One could envisage that the action of such a compound, from a stereochemical point of view, is equivalent to that of a mixture of diastereoisomers in rapid equilibrium, the interaction with the enzymatic site shifting the equilibrium towards the compound more refined. Other potential benefits may also result, such as a simplification of the synthesis methods (elimination of stereochemical problems) and greater resistance of such analogs to modified skeletons with respect to the action of peptidases. The method of the present invention makes it possible to introduce a wide variety of side chains, proteogenic or non-proteogenic, in chosen positions. This allows on the one hand to mimic most natural and unnatural amino acids and on the other hand to introduce on the pseudopeptide skeleton side chains capable of modulating its biophysical characteristics. The introduction of groups promoting the passage of these analogs through cell membranes (lipophilic chains) or increasing their solubility in the plasma medium (perfluorinated groups for example) makes it possible to modulate or even optimize the bioavailability of these compounds.

Two ways of synthesizing aza-β ³ -amino acid monomers have been developed, depending on the nature of the side chains which it is desired to mimic:

- Either by bromoacetylation of N, N'-disubstituted hydrazines, deprotection of the orthogonally protected monomer leading to the aza β amino acid desired with yields of the order of 60-80%.

G _p

R ¹ : H CH ₃ CH (CH ₃ ) ₂ CH ₂ CH (CH ₃ ) ₂ CH ₂ Ph (CH ₂ ) ₄ NHBoc

N ^α hGly N≈ _hA | _a N ^α hVal N ^α hLeu N ^α hPhe N ^α hLys

Either by reductive amination of glyoxylic acid.

H

IR ^η O

R I

CHO-C0 ₂ H

GP ^' GP. .NOT.

"M

I OH

H NaBH ₃ CN, EtOH, 2N HCI 60-85% N ^α haa

R ¹ - CH ₂ C0 ₂ tBu (CH ₂ ) ₂ SMe CH2 (C ₆ H ₄ ) OCH ₂ OC ₂ H ₅ (CH ₂ ) ₃ NHC = (NBoc) NHBoc N ^α hAsp N ^α h and N ^α hTyr N hArg

In the same way that it is possible today to prepare α-amino aldehydes from the pool of α-amino acids, it was possible for us from aza β - amino acids to obtain alcohol and aldehyde derivatives with good yields.

The monomers prepared in the context of the present invention, as well as the pool of variously substituted hydrazines that we have, constitute a starting point for the construction of new pseudodipeptide fragments. It was thus possible to synthesize, according to the following reaction scheme, orthogonally protected reduced hydrazinopeptoids.

After deprotection from C or N-terminal ends, it was possible:

- or to functionalize one or the other of the ends in order to obtain dipeptide analogs such as D, E and F.

- Or to couple a new aza β amino acid unit on one of the ends and to functionalize the other end in order to obtain tripeptide analogs such as G or H.

I Synthetic methodology

I) Aza-β ³ -amino acid monomers

1 - Synthesis of aza-β -amino esters N-protected 2

To a solution of hydrazine 1 (10 mmol, leq) in 50 ml of toluene, 3 equivalents of methyl bromoacetate (30 mmol) and 1.5 equivalents of K. ₂ CO ₃ (15 mmol) are added. The mixture is brought to reflux for 18 hours. The KBr formed is filtered on paper. Toluene and excess methyl bromoacetate are coevaporated with chloroform under reduced pressure. The aza-β -amino methyl ester 2, obtained in the form of a yellow oil, is sufficiently pure to be used in the subsequent reactions.

2a ^ = Boc, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂ Yield: 98%; Yellow oil

¹ H NMR (CDCl ₃ ) δ (ppm): 0.95 (d, 6H, J = 6.6Hz); 1.45 (s, 9H); 1.72 (m, 1H); 2.64 (d, 2H,

J = 7.5Hz); 3.70 (s, 2H); 3.73 (s, 3H); 6.54 (si, IH)

¹³ C NMR (CDCh) δ (ppm): 20.8 (q); 26.8 (d); 28.5 (q); 51.7 (q); 58.1 (t); 65.2 (t); 79.9

(s); 155.4 (s); 171.6 (s) Elementary analysis of Cι ₂ H ₂₄ N ₂ O ₄ Tr. C (55.13), H (9.34), N (10.80), Cale. C (55.36), H

(9.29), N (10.76).

YId: 96%; NMR yellow oil ^] H (CDCh) δ (ppm): 0.97 (d, 6H, J = 6.4Hz); 1.66 (m, 1H); 2.58 (d, 2H, J = 7.0Hz); 3.74 (m, 2H + 3H); 5.15 (s, 2H); 6.76 (si, 1H); 7.27 (s, 5H) ¹³ C NMR (CDCh) δ pm): 20.9 (q); 26.9 (d); 52.0 (q); 58.2 (t); 65.3 (t) 67.3 (t); 128.6 (d); 128.8 (d); 128.9 (d); 136.6 (s); 156.0 (s); 171.6 (s)

Elementary analysis of C, ₅ H ₂₂ N ₂ O Tr. C (61.13), H (7.43), N (9.68), Cale. C (61.21), H (7.53). N (9.52).

2c Ri = Boc, R ₂ = H, R ₃ = CH ₂ Ph

YId: 94%; Yellow oil

¹ H NMR (CDCh) δ (ppm): 1.64 (s, 9H); 3.93 (s, 2H); 3.98 (s, 3H); 4.36 (s, 2H); 7.53-7.63 (m, 5H); 6.95 (yes, IH).

Elementary analysis of C ₁₅ H2 ₂ N ₂ O ₄ Tr. C (61.18), H (7.50), N (9.58), Cale. C (61.21), H (7.53), N (9.52).

Yid: 90%; mp: 87 ° C

¹ H NMR (CDCh, δppm): 1.3 (s, 9H); 2.75 (s, 3H); 3.7 (s, 2H); 3.8 (s, 3H); 6.6 (s, 1H).

Elementary analysis of C ₉ H ₁₈ N ₂ O ₄ Tr. C (49.48), H (8.23), N (12.79), Cale. C (49.53), H

(8.31), N (12.84).

Yid: 95%, Oil

¹ H NMR (CDCh, δppm): 2.7 (s, 3H); 3.7 (s, 2H); 3.72 (s, 3H); 5.1 (s, 2H); 6.9 (broad s, 1 H); 7.4 (m, 5H). Elementary analysis of Cι ₂ H ₁₆ N ₂ O ₄ Tr. C (57.08), H (6.28), N (11.15), Cale. C (57.13), H (6.39), N (11.10).

2-Synthesis of aza-β-amino alcohol 3

(2) (3) To a solution of aza-β-amino methyl ester 2 (10 mmol, leq) in 50 ml of ethanol and tetrahydrofuran (65/35) are added 1.5 equivalents (15 mmol) of NaBH and 1.5 equivalents of LiCl (15 mmol). This mixture is left stirring at room temperature overnight. The reaction medium is acidified with 2N HCl and then extracted with twice 50ml of dichloromethane. The organic phase is washed successively twice with 50 ml of water, 50 ml of 2N NaHCO ₃ and 50 ml of a saturated NaCl solution. The organic phase is dried over sodium sulphate, then evaporated under reduced pressure to yield aza-β ³ -amino alcohol 3 which crystallizes slowly.

3a R, = Boc, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂

YId: 76%; Mp: 83 ° C

NMR ^] H (CDCh) δ (ppm)

1.11 (d, 6H, J = 6.5Hz); 1.61 (s, 9H); 1.93 (m, 1H); 2.28 (d, 2H, J = 7Hz); 2.90 (t, 2H,

J = 4.5Hz); 3.73 (t, 2H, J = 4.0Hz); 4.13 (s, 1H); 5.62 (s, 1H). ¹³ C NMR (CDCh) δ (ppm)

20.9 (q); 26.8 (d); 28.6 (q); 58.9 (t); 61.0 (t); 67.3 (t); 80.6 (s); 156.9 (s)

Elementary analysis of Cι, H ₂₄ N ₂ O _3: Tr. C (56.77), H (10.32), N (12.21), Cale. C (56.87), H

(10.41), N (12.06).

3b Ri = Z, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂ , Yield: 83%; Yellow oil

NMR ^] H (CDCh) δ (ppm): 1.13 (d, 6H, J = 6.5Hz); 1.95 (m, 1H); 2.68 (d, 2H, J = 7.0Hz);

2.93 (wide, 2H); 3.75 (t, 2H, J = 4.7Hz); 4.21 (s, 1H); 5.30 (s, 2H); 6.21 (s, 1H); 7.52 (s,

5H)

¹³ C NMR (CDCh) δ (ppm): 20.9 (q); 26.7 (d); 58.9 (t); 60.9 (t); 67.1 (t); 67.5 (t); 128.5 (d); 128.7 (d); 128.8 (d); 128.9 (d); 136.5 (s); 157.6 (s)

Elementary analysis of Cι ₄ H ₂₂ N ₂ O _3: Tr. C (63.02), H (8.22), N (10.33), Cale. C (63.13), H (8.33), N (10.52).

YId: 70%; oil

¹ H NMR (CDCh, δppm): 1.3 (s, 9H, Boc); 2.55 (s, 3H, CH ₃ ); 2.6 (t, 2H, CH ₂ ); 3.5 (t, 2H, CH ₂ ); 4 (broad s, 1H, OH); 5.9 (s, 1H, NH). Elementary analysis of C ₈ Hι ₈ N ₂ O ₃ Tr. C (50.42), H (9.45), N (14.63), Cale. C (50.51), H (9.54), N (14.73).

Yid: 80%; oil

¹ H NMR (CDCh, δppm): 2.7 (s, 3H, CH ₃ ); 2.8 (t, 2H, CH ₂ ); 3.4 (broad s, 1H, OH); 3.6 (t, 2H, CH ₂ ); 5.1 (s, 2H, CH ₂ ); 6.2 (broad s, 1H, NH); 7.4 (m, 5H, Ph).

Elementary analysis of CnHι ₆ N ₂ O ₃ Tr. C (58.85), H (7.22), N (12.33), Cale. C (58.91), H (7.19), N (12.49).

Mass CιιHι ₆ N ₂ O ₃ : [M + Na] ⁺ theoretical m / z: 247.1059; m / z found: 247,1060

3 - Synthesis of an aza-β-amino aldehyde 4

(3) (4)

To a solution of azaβ ³ -amino alcohol 3 (10 mmol, leq) in 30 ml of dichloromethane are added 3 equivalents of triethylamine (30 mmol), 3 equivalents of DMSO (30 mmol), followed by 3 equivalents of the oxidizing agent pyridine sulfide trioxide ( 30mmol) at a temperature of 15 ° C. This mixture is placed under stirring at room temperature for 4 hours, the organic phase is then washed twice successively with 30ml of water then 30ml of 2N NaHCO ₃ , and finally 30ml of a saturated NaCl solution. After drying over sodium sulfate, the organic solvent is evaporated off under reduced pressure, a brown oil is obtained which corresponds to aza-β ³ -amino aldehyde 4. 4a R, = Boc, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂

YId: 71%, Oil

N NMR (CDCl ₃ ) δ (ppm): 0.97 (d, 6H, J = 6.6Hz); 1.25 (s, 9H); 1.74 (m, 1H); 2.57 (d, 2H,

J = 7Hz); 3.65 (si, 2H); 6.10 (si, 1H); 9.77 (t, IH, J = 1.2Hz)

¹³ C NMR (CDCh) δ pm): 20.5 (q); 26.5 (d); 28.3 (q); 65.4 (t); 67.2 (t); 81.5 (s); 154.9 (s); 201.5 (d).

YId: 75%

1 H NMR (CDC1 ₃ , δ ppm): 0.9 (d, 6H); 1.8 (m, 1H); 2.55 (d, 2H); 3.7 (s, 2H); 5.2 (s, 2H); 6.9 (s, 1H); 7.3 (m, 5H); 9.75 (s, 1H).

C, ₄ H ₂₀ N ₂ O ₃ ,

Yield: 75% 1 H NMR (CDCI3, δ ppm): 1.3 (s, 9H); 2.55 (s, 3H); 3.6 (d, 2H); 6.2 (s, 1H); 9.75 (s, 1H). C ₈ H, ₆ N ₂ O ₃ , 188.22

4d R, = Z, R ₂ = H, R ₃ = CH ₃

Yield: 80% 1 H NMR (CDC1 ₃ , δ ppm): 2.8 (s, 3H); 3.65 (s, 2H); 5.1 (s, 2H); 6.8 (broad s, 1 H); 7.4 (m, 5H); 9.75 (s, 1H). C, ιH, ₄ N ₂ O ₃ , 222.24

II) Reduced orthogonally protected dimers

To a solution of aza-β ³ -amino aldehyde 4 (10 mmol, leq) in ether (10 ml) is added hydrazine Ibis (12 mmol, 1.2 equivalents), then the pH is adjusted to 4 by addition of 2N HCl . After 1 hour of stirring at room temperature, the ether is evaporated and the medium is dissolved in 10 ml of ethanol. Sodium cyanoborohydride (12mmol, 1.2 equivalents) is added in small portions and the mixture is left under stirring for 2 hours. The borylated complex is hydrolyzed to pH 1 by addition of 2N HCl, then the pH is readjusted to 7 by addition of 2N NaHCO ₃ . 10 ml of chloroform are added to the medium and the organic phase is washed successively with twice 20 ml of 2N HCl, then 20 ml of water saturated with NaCl. The organic phase is dried over sodium sulfate and the solvents are evaporated under pressure scaled down. Dimer 5 is obtained in the form of an oil or a solid washed twice with 20 ml of ether.

5a Ri = Boc, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂ , R ₄ = CH ₂ CH (CH ₃ ) ₂ , R ₅ = H, Re = Z Yield: 80%; Oil

1 H NMR (CDC1 ₃ ) δ (ppm)

0.82 (d, 2x6H, J = 6.8Hz); 1.34 (s, 9H); 1.64 (m, 2x1H); 2.28 (d, 2H, J = 6.3Hz); 2.38 (d, 2H,

J = 6.3Hz); 2.76 (m, 2x2H); 5.02 (s, 2H); 5.89 (si, 1H); 6.83 (si, 1H); 7.23 (s, 5H)

RN ¹³ C (CDCh) δ (ppm) 21.2 (q); 26.5 (d); 28.8 (q); 55.4 (t); 56.3 (t); 65.3 (t); 66.7 (t); 79.9 (s); 127.1 (d); 127.5

(d); 127.7 (d); 139.9 (s); 156.2 (s); 157.7 (s)

Elementary analysis of C ₂₃ H ₄₀ N ₄ O ₄ : Tr. C (63.21), H (9.23), Ν (12.83), Cale. C (63.41), H

(9.25), Ν (12.40).

Mass C ₂₃ H ₄₀ N ₄ O: [M + Νa] ⁺ theoretical m / z: 459.2947; m / z found: 459.2942

5b R, = Boc, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂ , R4 = H, R ₅ = CH ₂ CH (CH ₃ ) ₂ , Rβ = Z

Yid: 80%; Oil

¹ H NMR (CDCh) δ pm) 0.77-087 (d, 2x6H, J = 6.7Hz); 1.36 (s, 9H); 1.63 (m, 1H); 1.95 (m, 1H); 2.19-2.58 (wide,

2x2H); 2.85 (m, 2H); 3.14 (t, 2H, J = 6.9 Hz); 3.89 (si, 1H); 5.0 (s, 2H); 6.43 (si, 1H); 7.27

(s, 5H)

¹³ C NMR (CDCh) δφpm)

20.3 (q); 21.1 (q); 26.8 (d); 27.3 (d); 28.8 (q); 47.6 (t); 58.2 (t); 65.4 (t); 67.8 (t); 80.2 (s); 128.3 (d); 128.5 (d); 128.9 (d); 136.9 (s); 155.4 (s); 157.4 (s)

Elementary analysis of C ₂₃ H ₄₀ N ₄ O _4: Tr. C (63.13), H (9.44), N (12.80), Cale. C (63.41), H

(9.25), N (12.40).

Mass of C ₂₃ H ₄₀ N ₄ O ₄ [M + H] ⁺ theoretical m / z: 437.3128; m / z found: 437.3119

5c Rj = Z, R ₂ = H, R ₃ = CH ₂ Ph, R4 = CH ₂ CH (CH ₃ ) ₂ , R ₅ = H, Re = Boc

YId: 80%

1 H-NMR (CDCI ₃ , δ ppm): 0.9 (d, 6H, 2xCH ₃ ); 1.4 (s, 9H, Boc); 1.75 (m, 1H, CH); 2.35 (d, 2H, CH ₂ ); 2.95 (m, 4H, 2xCH ₂ ); 4.1 (s, 2H, CH ₂ ); 5.2 (s, 2H, CH ₂ ); 5.75 (s, 1H, NH); 6.9 (s, 1H, NH); 7.3 (m, 10H, 2xPh). ¹³ C NMR (CDCI ₃ , δ ppm): 21.1 (q), 26.7 (d), 28.5 (q), 56.1 (t), 56.6 (t), 58.9 (t), 67.2 (t), 80.6 (s) , 128.4 (d), 128.7 (d), 128.9 (d), 129.1 (d), 129.7 (d), 135.8 (d), 137.1 (d), 159.9 (s), 161.2 (s).

Mass of C ₂₆ H ₃₈ N ₄ O ₄ : [M + Na] ⁺ theoretical m / z: 493.2791; m / z found: 493.2787

5d R, = Boc, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂ , R "= CH ₃ , R _s = H, R _Ô = Z

YId: 84%

1 H NMR (CDCI ₃ , δ ppm): 0.8 (d, 6H, 2xCH ₃ ); 1.35 (s, 9H, Boc); 1.65 (m, 1H, CH); 2.25 (m, 2H, CH ₂ ); 2.45 (s, 3H, CH ₃ ); 2.6 (m, 4H, 2xCH ₂ ); 5.1 (s, 2H, CH ₂ ); 6.75 (s, 1H, NH); 7.4 (m, 5H, Ph).

¹³ C NMR (CDCI ₃ , δ ppm): 20.5 (q), 21.0 (q), 26.4 (d), 28.5 (q), 47.6 (q), 55.3 (t), 56.9 (t), 62.1 (t) , 66.2 (t), 82.1 (s), 128.4 (d), 128.7 (d), 128.9 (d), 136.8 (d), 158.3 (s), 161.2 (s).

Mass of C ₂ iH ₃₆ N ₄ O: [M + Na] ⁺ m / z theoretical:; m / z found:

5th Ri = Boc, R ₂ = H, R ₃ = CH ₂ Ph, R, = CH ₂ CH (CH ₃ ) ₂ , R ₅ = H, R ₆ = Z

Yield: 40% 1 H NMR (CDCI ₃ , δ ppm): 0.9 (d, 6H, 2xCH ₃ ); 1.4 (s, 9H, Boc); 1.8 (m, 1H, CH); 2.35 (d, 2H, CH ₂ ); 2.95 (m, 4H, 2xCH ₂ ); 4.1 (s, 2H, CH ₂ ); 5.1 (s, 2H, CH ₂ ); 6.4 (s, 1H, NH); 6.9 (s, 1H, NH); 7.3 (m, 10H, 2xPh).

¹³ C NMR (CDCI ₃ , δ ppm): 21.2 (q), 26.6 (d), 28.6 (q), 56.2 (t), 56.7 (t), 58.9 (t), 67.2 (t), 80.9 (s) , 128.4 (d), 128.7 (d), 128.9 (d), 129.4 (d), 129.7 (d), 135.8 (d), 137.1 (d), 159.7 (s), 161.3 (s).

Mass of C ₂₆ H ₃₈ N ₄ O ₄ : [M + Na] ⁺ theoretical m / z: 493.2791; m / z found: 493.2786

III) Deprotection of reduced hydrazino azapeptoids

(5) (6)

The reduced azrazptoid hydrazino 5 (10 mmol, leq) is dissolved in a 50/50 mixture (15 ml) of dichloromethane and trifluoroacetic acid. The medium is left under stirring for 3 hours. The solvent is evaporated and the residue is dissolved in 10 ml of water. The aqueous phase is washed with twice 15 ml of ether. The pH is then brought back to 7 using

NaHCO ₃ 2N and the organic phase is washed with 2 times 50ml of water. After drying on sulfate of sodium the organic phase is evaporated under reduced pressure. Product 6 is obtained in the form of an oil.

6a NH ₂ -N- Bu- (CH ₂ ) ₂ -N-azaLeu-OBz R ₃ = CH ₂ CH (CH ₃ ) ₂ , R4 = CH ₂ CH (CH ₃ ) ₂ , R ₅ = H, R ₆ = Z

YId: 74%, NMR Oil ^] H (CDCh) δ φpm)

1.15 (d, 2x6H, J = 6.6Hz); 2.01 (m, 2H); 2.47 (d, 2H, J = 6.8Hz); 2.52 (broad, 2H); 2.78 (t, 2H, J = 4.3Hz); 3.14 (large, 2H); 3.24 (large, 2H); 5.34 (s, 2H); 6.48 (si, 1H); 7.56 (m, 5H) ¹³ C NMR (CDCh) δ φpm)

21.1 (q); 26.2 (d); 26.6 (d); 56.1 (t); 58.3 (t); 66.9 (t); 70.9 (t); 128.4 (d); 128.8 (d); 128.9 (d); 136.9 (s); 156.9 (s) Cι ₈ H ₃₂ Ν ₄ O ₂ , 336.47

6b NH ₂ -NBz-N-azaLeu-OBz

R ₃ = CH ₂ Ph, R "= CH ₂ CH (CH ₃ ) ₂ , R ₅ = H, Re = Z

Yield: 67%, ^Oil} NMR H (CDCl₃) δ φpm)

0.90 (d, 6H, J = 6.6Hz); 1.75 (m, 1H); 2.58 (d, 2H, J = 6.8Hz); 3.12 (large, 2H); 3.28 (large, 2H); 4.18 (s, 2H); 5.17 (s, 2H); 6.32 (si, 1H); 7.39 (m, 5H), 7.47 (m, 5H)

IV) - Refunctionalization of the reduced azapeptoid hydrazino

The N-azapeptoid 6 deprotected hdyrazino solution at the N-terminus

(2mmol, leq) in distilled dichloromethane (10ml) is cooled to 0 ° C in an ice and salt bath. Distilled triethylamine (2.2 mmol, l. Leq) is added and the bromoacetyl bromide (2.2 mmol, l. Leq) in dichloromethane (10 ml) is added dropwise over one hour. The mixture is then left under stirring at room temperature for 5 hours, then washed 3 times with 20ml of water. The organic phase is dried over sodium sulfate and the solvent is evaporated under reduced pressure. The reduced analog 7 is obtained in the form of a solid which slowly precipitates when cold in ether and is recrystallized from ether.

7a BrCH ₂ CO-NHN / Bu- (CH ₂ ) ₂ -N-aza-Leu-OBz Ri = -CO-CH ₂ -Br, R ₂ = H, R ₃ = CH ₂ CH (CH ₃ ) ₂ , R "= CH ₂ CH (CH ₃ ) ₂ , R ₅ = H, RÔ = Z

m.p. , Yid: 55%,

NMR ^} H (CDCh) δ φpm)

0.96 (d, 2x6H, J = 6.6Hz); 1.78 (m, 2x1 H); 2.47 (d, 2H, J = 7Hz); 2.56 (d, 2H J = 7Hz); 2.91 (wide, 2H); 2.97 (broad, 2H); 3.79 (s, 2H); 5.16 (s, 2H); 5.90 (si, 1H); 7.03 (si, 1H); 7.38

(m, 5H)

¹³ C NMR (CDCh) δ pm)

18.7 (q); 19.6 (q); 28.5 (d); 29.5 (d); 55.5 (t); 61.75 (t); 62.27 (t); 66.44 (t); 127.6 (d);

128.4 (d); 128.6 (d); 136.8 (s); 159.0 (s); 175.7 (s) Elementary analysis of C ₂₀ H ₃ N ₄ θ ₃ Br: Tr. C (52.52), H (7.27), N (12.25); Cale. C (52.48),

H (7.27), N (12.32).

V) - Refunctionalization of the azapeptoid hydrazino reduced by a boronic acid:

To a stirred solution of reduced hydrazino azapeptoid 6 (5 mmol, 1 equi) in 5 ml of ether is added in small portions the borylated aldehyde (5.5 mmol, 1.1 equi) in solution in ether (10 mL) . The medium is left under stirring for 1 hour. The oil obtained is chromatographed.

/ HB (OH) ₂ -Ph-HC = N ^α hPhe-N-azaLeu-Z: R ,, R ₂ = (HO) ₂ Bm- (C ₆ H ₄ ) CH =, R ₆ = Z,

mp = ° C; 1 H NMR (CDC1 ₃ ) δ (ppm) 0.87 (d, 6H, J = 6.5 Hz), 1.75 (m, 1H), 2.46 (wide, 2H),

3.04 (wide, 2H), 3.52 (wide, 2H), 3.72 (wide, 2H), 4.24 (s, 2H), 5.16 (s, 2H), 7.09 (m, IH), 7.22 (m, 10H), 7.37 (large, IH), 7.84 (d, IH), 8.10 (s, 2H), 10.0 (s large, IH). ¹³ C NMR (COC \ ₃ ) δ (ppm) 21.0 (q), 26.3 (t), 54.0 (t), 66.5 (t), 66.9 (t), 67.9 (t), 128.1, 128.6,128.8, 129.1, 129.3, 128.6, 128.8, 131.1, 131.8, 135.9, 136.9, 141.1, 170.8 (s).

Elementary analysis of C ₂₈ H ₃₅ N ₄ 0 ₄ B: Tr.: C, (65.39); H, 6.31; N, 11.23; B, 1.77. Calc.C, 65.13; H, 6.44; N, 10.85; B, 2.09.

wB (OH) ₂ -Ph-HC = N ^α hPhe-N-azaLeu-Z: R ,, R ₂ = (HO) ₂ Bm- (C ₆ H ₄ ) CH =, R ₆ = Z, X = CH ₂ , R ₃ = i-Bu, R ₄ = i-Bu, R ₅ = H

mp = ° C; NMR ^! H (CDC1 ₃ ) δ (ppm) 0.87 (d, 6H, J = 6.5 Hz), 1.75 (m, IH), 2.46 (wide, 2H),

3.04 (wide, 2H), 3.52 (wide, 2H), 3.72 (wide, 2H), 4.24 (s, 2H), 5.16 (s, 2H), 7.09 (m, IH), 7.22 (m, 10H), 7.37 (large, IH), 7.84 (d, IH), 8.10 (s, 2H), 10.0 (s large, IH). NMR ^{! 3} C (CDC1 ₃ ) (ppm) 21.0 (q), 26.3 (t), 54.0 (t), 66.5 (t), 66.9 (t), 67.9 (t), 128.1, 128.6,128.8, 129.1, 129.3 , 128.6, 128.8, 131.1, 131.8, 135.9, 136.9, 141.1, 170.8 (s). Elementary analysis of C ₂₈ H ₃₅ N ₄ 0 ₄ B: Tr.: C, (65.39); H, 6.31; N, 11.23; B, 1.77. calc.c,

65.13; H, 6.44; N, 10.85; B, 2.09.

II - Biological activity of reduced compounds

In eukaryotic cells, the vast majority of proteins involved in regulating the cell cycle are degraded by the proteasome

This degradation pathway is very precisely regulated and is very selective both in the choice of proteins to be degraded and in the choice of the time of the cell cycle phase when the protein will be degraded. The ubiquitin-proteasome system also plays a very important role in the control of cell division

Too much proteasome activity can therefore be the cause of the presence of an abnormally low level of proteins involved in limiting cell proliferation such as tumor suppressors. Likewise, reduced proteasome activity may be responsible for the presence of an abnormally high amount of proteins involved in stimulating cell proliferation such as oncogenes. The proteasome also plays a very important role in the entry into apoptosis of cells. Some proteasome inhibitors can cause apoptosis to be inhibited and others to activate apoptosis. A current hypothesis is that certain proteins controlling the entry into apoptosis are continuously synthesized but continuously degraded by the proteasome. This would be one of the reasons why an inhibition of the proteasome would have the direct consequence of an induction of apoptosis.

Proteasome inhibitors therefore have very serious anticancer potential and the numerous clinical studies currently underway to assess their role as an adjuvant in chemotherapy protocols demonstrate this importance.

Antiproliferative effect of the compounds on cancer lines

The inventors studied the effect of pseudopeptides comparatively on normal and tumor cell lines this in order to determine the cell specificity of action of the compounds. They analyzed cell growth as well as cell viability under the effect of the reduced pseudo peptide 7a on the following lines.

Skov3: ovarian cancer (human)

OvCar3: ovarian cancer (human)

L1210: Mouse leukemia

Antiproliferative action of pseudodipeptides on the various tumor lines

The cytotoxicity of pseudopeptides is evaluated by the ability of viable cells to reduce the bromide of 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium (or MTT, yellow product soluble in water) in crystals formazan, a product insoluble in water, but soluble in DMSO (purple in color) via mitochondrial dehydrogenases. The quantity of viable cells is therefore proportional to the quantity of crystals formed. A large number of proteasome inhibitors have been shown to have antiproliferative action on cancer lines. The antiproliferative action of the compounds has therefore been looked at on several cancer lines.

Tested on the various lines mentioned, compound 7a has proven to be a very good antiproliferative compound for the 3 tumor lines.

Claims

1. Pharmaceutical composition comprising, in combination with a pharmaceutically acceptable vehicle, a compound of the following general formula (I):

in which :

"Y represents CH ₂ or CO,

"n represents an integer from 1 to 10, in particular n represents 1 or 2, provided that when n represents 1, Y represents CH ₂ , and that when n is greater than 1, at least one of the groups Y in the formula (I) represents CH ₂ , "Ri and R _ό , independently of one another, represent: o a hydrogen atom, o a group which can be used in the context of the protection of nitrogen atoms in peptide synthesis , such as the group BOC, FMOC or Z, o a group of formula -COR, or -CH ₂ COR in which R represents: a hydrogen atom, with the proviso that when Ri is hydrogen, the latter occurs optionally in the form of a salt soluble in aqueous solvents, such as a trifluoroacetate salt, an alkyl group of 1 to 10 carbon atoms, optionally substituted by one or more halogen atoms, such as the groups R representing -CF ₃ or a group -CH ₂ X, X representing a halogen atom such as Cl or Br, a group -COOR _a in leq uel R _a represents H or an alkyl group, such as a methyl or ethyl group, a primary amino group -NH ₂ or an amine II ^re or III ^re ,> an alkoxy group, such as a methoxy group -OMe, or ethoxy

-OEt, a phenyl group, a pyridinium group, such as the group of formula

"R ₂ , R ₃ ," and R ₅ , independently of each other, representing: o a hydrogen atom, o an alkyl group of 1 to 10 carbon atoms, optionally substituted, in particular by one or more atoms halogen or by one or more amino or phenyl groups, such as methyl, butyl, isobutyl, - (CH ₂ ) ₄ NH ₂ , -CH ₂ Ph, - (CH ₂ ) ₄ NHBoc, - (CH ₂ ) ₃ NHC (NH ₂ ) = NH, "or Ri in association with R ₂ , or R _ô in association with R ₅ , represent a group of formula _ _CH //

2. Pharmaceutical composition according to claim 1, comprising, in association with a pharmaceutically acceptable vehicle, a compound of general formula (I), in which:

"R2 represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group,

"R ₃ represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group, or R ₃ represents a benzyl group," one of R "or of R ₅ represents H, while the the other represents an alkyl group as defined above, and R ₆ represents H or a protective group BOC or Z,

"n represents 1 or 2,

"Y is as defined in claim 1.

3. Pharmaceutical composition according to claim 1 or 2, comprising, in association with a pharmaceutically acceptable vehicle, a compound of formula

^• general (I), in which:

- R2 represents H, - R ₃ represents an isobutyl group, or a benzyl group,

- R ₄ represents H, or a methyl or isobutyl group,

- R ₅ represents H, or an isobutyl group,

- R _Ô represents a BOC or Z protective group,

- n represents 1,

- Y represents CH2.

4. Pharmaceutical composition according to one of claims 1 to 3, characterized in that the compound of formula (I) is chosen from those of the following formula:

H

I .N

Boc ^'

5. Pharmaceutical composition according to one of claims 1 to 4, comprising, in association with a pharmaceutically acceptable vehicle, a compound of general formula (I), in which:

- Ri is different from R ₂ , - R ₅ is different from R ₆ , and

- The group -N (Rι) (R ₂ ) is different from the group -N (R ₅ ) (R ₆ ).

6. Pharmaceutical composition according to one of claims 1 to 5, characterized in that it is in a form which can be administered intraperitoneally, in particular at a rate of approximately 5 mg / kg / day.

7. Use of compounds of formula (I) as defined in one of claims 1 to 5, for the preparation of a medicament intended for the treatment of cancers such as cancers of the liver, colon, breast, melanomas , by inducing the apoptosis of cancer cells.

8. Compounds of general formula (I) below:

in which: • Y represents CH ₂ or CO, "n represents an integer from 1 to 10, in particular n represents 1 or 2, provided that when n represents 1, Y represents CH ₂ , and that when n is greater than 1 , at least one of the groups Y in formula (I) represents CH ₂ , "Ri and R _Ô , independently of one another, represent: o a hydrogen atom, o a group which can be used in the context protection of nitrogen atoms in peptide synthesis, such as the BOC, FMOC or Z group, o a group of formula -COR, or -CH ₂ COR in which R represents: a hydrogen atom, provided that when R 1 is hydrogen, the latter is present, where appropriate, in the form of a salt soluble in the aqueous solvents, such as a trifluoroacetate salt,> an alkyl group of 1 to 10 carbon atoms, optionally substituted by one or more halogen atoms, such as the groups R representing -CF ₃ or a group -CH ₂ X, X representing a halogen atom such as Cl or Br, a group -COOR _a in which R _a represents H or an alkyl group, such as a methyl or ethyl group, a primary amino group -NH ₂ or a amine II ^re or Ilf ^e , an alkoxy group, such as a methoxy group -OMe, or ethoxy group -OEt, a phenyl group, a pyridinium group, such as the group of formula - CH— N)

Br ^" " R ₂ , R ₃ , R ₄ and R ₅ , independently of each other, representing: o a hydrogen atom, o an alkyl group of 1 to 10 carbon atoms, optionally substituted, in particular by a or more halogen atoms or by one or more amino or phenyl groups, such as methyl, butyl, isobutyl, - (CH ₂ ) ₄ NH ₂ , -CH ₂ Ph, - (CH ₂ ) ₄ NHBoc, - ( CH ₂ ) ₃ NHC (NH ₂ ) = NH, "or Ri in association with R ₂ , or in association with R ₅ , represent a group of formula

excluding the compounds corresponding to the following formulas (II), (III), (IV) and

A representing a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a C ₅ Hn group or a group

B representing a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a C ₅ Hn group or a C ₆ Hι _{3 group} .

9. Compounds according to claim 8, of general formula (I) in which: "Ri represents a protective group BOC, or Z, or a group -COCH ₂ X, X representing a halogen atom such as Cl or Br, or Rj represents H, provided that when Ri represents H, this is optionally in the form of a salt, such as a trifluoroacetate salt of formula

"R ₃ represents H or an alkyl group of 1 to 10 carbon atoms, such as an isobutyl group, or R ₃ represents a benzyl group,

One of R ₄ or R ₅ represents H, while the other represents an alkyl group as defined above, and R ₆ represents H or a protective group BOC or Z,

• n represents 1 or 2,

"Y is as defined in claim 8.

10. Compounds according to claim 8 or 9, of general formula (I) in which:

R ₂ represents H,

R ₃ represents an isobutyl group, or a benzyl group,

R represents H, or a methyl or isobutyl group,

R ₅ represents H, or an isobutyl group,

R ₆ represents a BOC or Z protecting group, n represents 1,

Y represents CH ₂ .

11. Compounds according to one of claims 8 to 10, of general formula (I) in which:

- Ri is different from R ₂ ,

- R ₅ is different from R ₆ , and

- The group -N (Rj) (R ₂ ) is different from the group -N (R ₅ ) (R ₆ ).

12. Compounds according to one of claims 8 to 11, of the following formulas

H CH,

I (5d)

.N- N ^ / '

Boc ^' ^' N ^' N

CH ₂ -CH (CH) H

"-V2

15

30

13. Process for the preparation of a compound according to one of claims 8 to 12, characterized in that it comprises the following stages: - reaction of the compound of formula (1) below

R ₃ in which Ri, R2, and R ₃ are as defined in claim 8, with methyl bromoacetate _B / ^{^} - ^ ^ -OMe

O

which leads to obtaining the aza-β ³ -amino esters of formula (2) below

^ - ^ ^0MC (2)

R ₃ O in which Ri, R ₂ , and R ₃ are as defined above,

treatment of the compound of formula (2) obtained in the previous step with NaBH ₄ and LiCl, which leads to the production of the aza-β ³ -amino alcohols of formula (3) below

^R 3 in which Ri, R ₂ , and R ₃ are as defined above,

- treatment of the compound of formula (3) obtained in the previous step with triethylamine, DMSO, and the oxidizing agent pyridine sulfide trioxide, which leads to the production of aza-β-amino aldehydes of formula (4) next

in which Rj, R ₂ , and R ₃ are as defined above, - reaction of the compound of formula (4) obtained in the preceding step with the compound of formula (Ibis) following R ₄

_H - ^N - _N ^ ⁶ (Ibis)

I 5 in which P ^, R ₅ , and R _Ô are as defined in claim 8, which leads to obtaining compounds of formula (5) below

in which Ri, R ₂ , R ₃ R ₄ , R ₅ , and R _Ô are as defined above,

in which R ₃ R ₄ , R ₅ , and R _Ô are as defined above,

- If necessary, reaction of the compound of formula (6) obtained in the previous step with a compound of formula X-CH -CO-X in which X represents a halogen atom such as Cl or Br, which leads to obtaining compounds of formula (7) below

in which X, R ₃ R ₄ , R ₅ , and R ₆ are as defined above,

- if necessary, reaction of the compound of formula (6) obtained in the previous step with a borylated aldehyde of formula

which leads to obtaining compounds of formula (8) below

wherein R ₃ R, R ₅ , and R ₆ are as defined above.