WO2004035584A1

WO2004035584A1 - Pharmaceutical compounds specifically inhibiting smooth muscle pde5, pharmaceutical compositions containing same and therapeutic uses thereof

Info

Publication number: WO2004035584A1
Application number: PCT/FR2003/003017
Authority: WO
Inventors: épouse LUGNIER Claire Renée Jeanne MOREAU; Jacques Kameni Tcheudji; Luc Lebeau
Original assignee: Universite Louis Pasteur; Centre National De La Recherche Scientifique
Priority date: 2002-10-16
Filing date: 2003-10-13
Publication date: 2004-04-29
Also published as: FR2845993A1; AU2003288318A1; FR2845993B1; AU2003288318A8

Abstract

The invention concerns the field of synthetic organic chemistry applied to pharmaceutics and aims at providing novel compounds, pharmaceutical compositions containing same and pharmaceutical uses thereof. Said novel compounds exhibit enhanced selective efficacy on the smooth muscle PDE5 and can be used for treating hypertension, pulmonary hypertension, renal disease or male sexual impotence without potentiating an anti-aggregating treatment. The compounds are of formula I to VI wherein the substituents are such as defined in the description.

Description

Smooth muscle PDE5 specific inhibitor pharmaceuticals, pharmaceutical compositions containing them and therapeutic uses

The present invention relates to the field of synthetic organic chemistry applied to the pharmaceutical field and relates to new pharmacologically active compounds, the pharmaceutical compositions containing them as well as their pharmaceutical uses. These new compounds are capable of selectively inhibiting PDE5 and are therefore likely to therefore exhibit vasodilator properties with the particularity of not having an anti-aggregating effect.

The present invention relates more specifically to the identification, purification and characterization of two subtypes of enzymes which specifically hydrolyze cyclic GMP (cyclic nucleotide phosphodiesterases type 5, PDE5) in vascular smooth muscle and in blood platelets .

It also relates to the demonstration of their specific tissue localization, their structural differences and their different sensitivities to pharmacological substances. These differences have the consequence of being able to specifically inhibit the hydrolysis of cGMP in smooth muscle so as to obtain a relaxing effect at concentrations which do not act on the PDE5 of the platelets. Until this invention, the PDE5s of smooth muscle and of platelets were considered to be identical, characterized by the same sensitivity to pharmacological compounds, in particular to Viagra® from the company Pfizer recently put on the market.

The compounds according to the invention make it possible in particular to target, from the therapeutic point of view, either arterial hypertension and / or pulmonary hypertension, renal failure or sexual impotence without potentiating the anti-aggregating treatments commonly used in heart failure, specifically by inhibiting PDE5 of smooth muscle. It is known that cyclic GMP (cGMP) plays a major role in the control of vasodilation and platelet aggregation. This nucleotide cyclic is specifically degraded by an enzyme called during its characterization GMPc-PDE (Lugnier et al., 1986), then PDE V and in the new nomenclature, PDE5.

The first specific inhibitor described for this enzyme is the compound M&B 22948 (Lugnier et al., 1986) now called zaprinast. It inhibits PDE5 from smooth vascular and pulmonary muscles in the same way as those from blood platelets. It is this compound which served as a starting point for designing the active ingredient known as sildenafil, the active ingredient in VIAGRA ^® which acts similarly on PDE5s from various tissues.

Indeed, the only studies currently available concerning the synthesis of PDE5 inhibitor have been carried out on the PDE5 of beef lung which have made it possible to develop from the chemical structure of zaprinast new molecules a thousand times more powerful (Ki = 4 nM) and very specific such as DMPPO (Glaxo) and said sildenafil (Pfizer) which also act on the corpora cavernosa, the latter molecule having been marketed by the company Pfizer for the treatment of sexual impotence.

The problem posed by the present invention is therefore to propose new pharmacological compounds which act as selective inhibitors of PDE5 of smooth muscle, in particular vascular, whose activity on this PDE5 is at least 10 times more powerful than that on platelet PDE5.

To this end, biochemical, physico-chemical and structural differentiation of vascular and platelet PDE5 has been carried out, leading to the development of families of newly synthesized inhibitors, which unexpectedly and surprisingly are 50 times more powerful on vascular PDE5. than on platelet PDE5, 60 times more powerful than VIAGRA ^® by exhibiting an inhibition constant (K _; ) of 32 pM.

Its first object is therefore the six main families of compounds whose formulas are:

in which :

- R ¹ , R ² , R ⁸ R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ _: R ¹⁹ , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ which may be identical or different, represent a proton, an alkyl group, an alkyl group substituted by one or more halogen atoms, an acyl group, an acyl group substituted by one or more halogen atoms, a hydrocarbon group having one or more ethylenic bonds, an aralkyl group, an aryl group, a group hydrocarbon which may be unsaturated and / or contain one or more heteroatoms;

- R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ which may be identical or different, represent a proton, OR ⁸ , NR ⁹ R ¹⁰ , X ¹ S0 ₂ R ¹¹ , X ² SO ₂ (X ³ R ¹² ), SO _n R ¹³ ,

SO ₂ (NR ¹⁴ R ¹⁵ ), X ⁴ P (Y ¹ ) (X ⁵ R ¹⁶ ) (X ⁶ R ¹⁷ ), X ⁷ P (Y ² ) (X ⁸ R ¹⁸ ) R ¹⁹ ,

P (Y ³ ) (X ⁹ R ²⁰ ) (X ¹⁰ R ²¹ ), P (Y ⁴ ) (X ^π R ²² ) R ²³ and P (Y ⁵ ) R ²⁴ R ²⁵ , n can be equal to 0, 1 or 2;

- R ¹² , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ R ²⁰ , R ²¹ and R ²² which may be the same or different, represent a proton, an alkyl group, an alkyl group substituted by one or more atoms halogen, a hydrocarbon group having one or more ethylenic bonds, an aralkyl group, an aryl group, a hydrocarbon group which may be unsaturated and / or have one or more heteroatoms, an ammonium group, an ion of formula W y _v , in which M represents a metal and v is the valence state of the metal M, or an internal cation;

- X ¹ to X ¹¹ which may be identical or different, represent O, S or

NR ²⁴ ;

- Y ¹ to Y ⁵ which may be identical or different, represent O, S or Se,

and in which:

- At least two groups among R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are different from a proton;

if R ¹ and R ² are protons, R ⁶ is different from SO ₂ R ¹³ , SO ₂ (NR ¹⁴ R ¹⁵ );

if 3 of R ³ R ⁴ , R ⁵ , R ⁶ and R ⁷ are protons, the other 2 cannot be OR ⁸ ;

- if R ³ is a methoxy or w-propyloxy group and if R ⁴ , R ⁵ and R ⁷ are protons, the group R ⁶ cannot contain the carbonyl-α, β-unsaturated unit, cannot be NH ₂ , a urea or thiourea.

More particularly, the preferred compounds according to the invention have structures where:

- R, R, R, R, and R are hydrogen atoms;

- R ³ is the n-propyloxy group;

- RR ⁶⁶ eesstt llee ggrroouuppee NNHHCC ((OO)) CCHH ₂₂ OCH ₂ CH ₂ OBn; where Bn is the benzyl group (-CH ₂ C ₆ H ₅ )

Furthermore, some of the 6 aforementioned structures are in equilibrium when R ¹ and / or R ² are protons. The present invention also relates to the use of at least one compound according to the invention as a specific inhibitor of PDE5 in smooth muscle. It also relates to the use for obtaining a medicament comprising as active principle at least one compound of general formula I to VI according to the invention for the preventive or curative treatment of a disease requiring inhibition of smooth muscle PDE5.

Finally, the present invention also relates to a method of treatment or prevention comprising the administration to a mammal of a therapeutically effective amount of at least one compound of general formula I to VI or of a pharmaceutical derivative acceptable (salt, ester, etc.) of the said compound or compounds according to the present invention.

The invention will be better understood from the detailed description below, which relates to a preferred embodiment, given by way of non-limiting example.

In the context of the present invention, first of all, homogeneous purification was carried out of PDE5 from vascular smooth muscle of beef aorta and PDE5 from human platelets by ion exchange liquid chromatography, by ion chromatography. affinity using a specific ligand and elution by an excess of cGMP. Then, the molecular weights were characterized by SDS-PAGE electrophoresis and immunoblotting using an anti-PDE5 antibody from beef lung (Dr J. Corbin, Vanderbilt University, Nashville, USA), vascular and platelet PDE5 showing that these two proteins have respective masses of 90 kDa and 85 kDa.

MALDI-TOF analysis of the tryptic peptides of vascular and platelet PDE5s obtained in comparison with the peptides contained in the databases indicate that the purified proteins are indeed PDE5s and that these two PDE5s differ structurally from each other.

Under the same conditions, recombinant human PDE5 has a molecular mass of 94 kDa and that of human aortic PDE5 is 96 kDa.

These two proteins purified from vascular tissue and blood platelets led to the determination of the compounds according to the invention, namely specific inhibitors of cGMP hydrolysis in smooth muscle which cannot act at the same concentrations on the platelets. Thus it was possible to determine new powerful molecules, devoid of unwanted effects at the platelet level and limiting undesirable effects. by working on these two target proteins from the archetype inhibitor.

In a completely surprising and unexpected manner, the inventors of the compounds in accordance with the present invention noted that the latter had the advantage of dissociating the inhibitory effect of PDE5 from smooth muscle compared to the inhibition of PDE5 from platelets on which the new inhibitors only work at 50 times the concentration. This has the consequence of offering the possibility of treating arterial or pulmonary hypertension, renal failure as well as sexual impotence by avoiding potentiating an anti-aggregating treatment.

In the context of the two-dimensional crystallization of PDE5, the inventors have been led to graft onto the NH ₂ -zaprinast compound an anchoring chain which has given rise to the synthesis of the following potent and selective PDE5 inhibitors

- 2- (2-benzyloxy-ethoxy) -N- [3 - (7-oxo-6,7-dihydro-1H-

[1,2,3] triazolo [4,5- <i] pyrimidin-5-yl) -4-propoxy-phenyl] acetamide

(compound 3) of formula:

from which all the claimed compounds derive, the general formulas of which have been given above.

Table 1: Selectivity of compound 3 with respect to purified isoforms expressed by the ratio CI ₅₀ purified PDEs / CI ₅₀ PDE5 of smooth muscle

Compound 3 is 10,000 times more potent than zaprinast. 2- (2-hydroxy-ethoxy) -N- [3- (7-oxo-6,7-dihydro- \ H- [1,2,3] triazolo [4,5- d pyrimidin-5-yl) - 4-propoxy-phenyl] acetamide (compound 4) and

N- [3- (7-oxo-6,7-dihydro-1H- [1,2,3] triazolo [4,5-ûO pyrimidin-5-yl) -4- propoxy-phenyl] acetamide (compound 5) formulas:

Compound 4 Compound 5

Compound 3 is 88 times more potent than Compound 4 and 185 times more potent than Compound 5.

This highlights that the structure of compound 3 is essential for its action on human vascular PDE5.

Nevertheless, the aforementioned compounds 4 and 5 are 48 times and 24 times more powerful than zaprinast.

In addition, compounds 3, 4, and 5 act similarly on purified smooth muscle PDE5 and on recombinant human PDE5.

Example of synthesis and characterization of the aforementioned compound 3

An example of synthesis of compound 3 can be summarized by the following procedure:

Synthesis example of 2- (2-benzyloxy-ethoxy) -iV-r3 - (7-oxo-6,7-dihydro- 1H- [1,2,3] triazolo | ^" 4,5- fl pyrimidin-5- yl) -4-propoxy-phenyl] acetamide 3 (compound 3)

A mixture of 2-benzyloxyethoxy acetic acid 1 (50 mg, 0.24 mmol), aminozaprinast 2 (Knowles, Philip; Lunt, Edward; Marshall,

Stuart Malcolm; Ford, Roger Edward. 8-Azapurin-6-ones. Ger. Offen.

(1978), 45 pp. CODEN: GWXXBX DE 2747199 19780427 CAN 89: 24359

AN 1978: 424359; Knowles, Philip; Lunt, Edward; Marshall, Stuart

Malcolm; Ford, Roger Edward. Aza-8-purin-6-one derivatives. Patentschrift (Switz.) (1982), 9 pp. Division of Patentschrift (Switz.) Appl.

No. 12,868. CODEN: SWXXAS CE 627755 A 19820129 CAN 97: 23816 AN

1982: 423816) (50 mg, 0.17 mmol), of N, N'-dicyclohexylcarbodiimide

(72 mg, 0.34 mmol) and 4-dimethylaminopyridine (12 mg, 0.10 mmol) is stirred for 5 hours at room temperature in 5 ml of anhydrous THF. The solution is filtered and the filtrate is reduced in vacuo. The residue obtained is purified by chromatography on silica (CH ₂ Cl ₂ / EtOH 10: 0 to 9/1) to yield compound 3 (47 mg, 57%) in the form of a slightly yellow solid.

Characterization of compound 3

Mp (melting point): 74-75 ° C 1H-NMR (CDC1 ₃ , 300 MHz) δ 11.54 (s, 1H); 9.18 (s, 1H); 8.60 (d, J≈ 2.8 Hz, 1H); 7.78 (dd, J = 2.8 and 9.03 Hz, 1H); 7.38-7.25 (m, 5H); 6.92 (d, J = 9.0 Hz, 1H); 4.73 (s, 2H); 4.20 (s, 2H); 4.14 (t, J = 6.8 Hz, 2H); 3.88-3.85 (m, 2H); 3.76-3.74 (m, 2H); 2.00 (m, 2H); 1.15 (t, J = 7.5 Hz, 3H).

¹³ C-NMR (CDC1 _3, 75 MHz) δ 168.95, 167.64; 155.27; 154.73; 154.41; 154.14; 137.48; 131.71; 128.57 (2C); 127.97 (2C); 126.28; 122.87; 118.21; 113.60; 73.42; 71.76; 71.36; 70.38; 68.95; 22.35; 10.55.

MS - mass spectroscopy - (IC, NH ₃ ) mlz 479 [M + H] ⁺ (100%).

Example of synthesis of 2- (2-hydroxy-ethoxy) -N- [3-, 7-oxo-6., 7-dihydro-1H- [2,31triazolo [4,5-g / 1 pyrimidin-5-ylV4 -propoxy-phenyl1 acetamide (compound 4)

The aforementioned compound 3 (5.6 mg, 0.011 mmol) and 10% Pd / C (2 mg) are stirred under an atmosphere of hydrogen in methanol (2 ml) for 2 h. The catalyst is filtered through celite and the filtrate is reduced under vacuum to yield pure compound 4 (4.2 mg, 92%) in the form of a white solid.

Characterization of compound 4

TLC: R _f 0.2 (CH ₂ Cl ₂ / EtOH 4: 1).

1H-NMR (CDCl ₃ , / CD ₃ OD 1: 1, 300 MHz) δ 8.49 (d, 7 = 2.6 Hz, 1H); 7.88 (dd, J = 2.3 and 9.0 Hz, 1H); 7.11 (d, J = 9.0 Hz, 1H); 4.18 (t, J = 6.4 Hz, 2H); 4.12 (s, 2H); 3.79 (t, J = 4.0 Hz, 2H); 3.69 (t, J = 4.0 Hz, 2H); 1.95 (m, 2H); 1.08 (t, J = 7.5 Hz, 3H).

MS (IC, NH ₃ ) mlz 389 [M + H] ⁺ (100%). Example of synthesis of N-r3- (7-oxo-6,7-dihydro-1H-r 2,31triazolor4,5- <i1 pyrimidin-5-yl -4-propoχy-phenyl1 acetamide (compound 5).

Acetic acid (3.1 μl, 0.055 mmol), aminozaprinast 2 (15.8 mg, 0.055 mmol) and N, N'-dicyclohexylcarbodϋmide (27.4 mg, 0.132 mmol) are stirred at temperature room temperature for 12 h in a THF / CH ₂ C1 ₂ 1: 1 mixture. The reaction mixture is reduced under vacuum and the residue is purified by chromatography on silica (EtOAc / EtOH 1: 0 to 1: 1) to yield compound 5 (16 mg, 89%) as a slightly ocher powder.

Characterization of compound 5

TLC: R _f 0.4 (CH ₂ Cl ₂ / EtOH 4: 1).

1H-NMR (DMSO-, 200 MHz) δ 11.80 (s, 1H); 10.11 (s, 1H); 8.12 (d, J = 2.4 Hz, 1H); 7.75 (dd, J = 2.4 and 8.8 Hz, 1H); 7.16 (d, J≈ 8.8 Hz, 1H); 4.06 (t, J = 6.3 Hz, 2H); 2.06 (s, 3H); 1.92-1.68 (m, 2H); 0.99 (t, J = 7.3 Hz, 3H).

¹³ C-NMR (DMSO- g, 50 MHz) δ 168.1; 155.8; 154.7; 152.9; 152.4; 132.7; 126.8; 123.2; 121.4; 121.0; 113.5; 70.3; 23.8; 22.0; 10.4. MS (IC, NH ₃ ) m / z 329 [M + H] ⁺ (100%).

Unless otherwise indicated, the following terms used in the present description and the present set of claims have the following meanings:

“Alkyl” denotes a linear saturated monovalent hydrocarbon radical having from 1 to 12 carbon atoms or a branched saturated monovalent hydrocarbon radical having from 3 to 12 carbon atoms, for example, methyl, ethyl, propyl, 2-propyl, butyl, etc. - "acyl" denotes a monovalent radical R-CO- as it appears in acids, anhydrides, acid halides, amides and esters.

- “aryl” denotes an aromatic hydrocarbon radical of optionally substituted phenyl type, that is to say a phenyl group which is optionally independently substituted with one or more hydrocarbon group (s) which may (may) be unsaturated ( s) and / or comprise one or more heteroatom (s) or substituted with one or more heteroatom (s).

- "aralkyl" denotes an aryl radical defined above substituted by an alkylene group, that is to say, by a linear saturated divalent hydrocarbon radical of 1 to 12 carbon atoms or a branched saturated divalent hydrocarbon radical of 3 to 12 carbon atoms containing at least one double bond, such as benzyl, phenylethyl, etc.

- “halogen” denotes a monovalent radical chosen from fluorine, chlorine, bromine and iodine.

According to a first characteristic, the compounds according to the present invention are characterized in that in the above formulas I to VI R ¹ , R ² , R ⁴ , R ⁵ , and R ⁷ are hydrogen atoms, R ³ is the group " -propyloxy, and R ⁶ is the group NHC (O) CH ₂ OCH ₂ CH ₂ OBn, Bn representing the benzyl group (-CH ₂ C ₆ H ₅ ).

According to another characteristic and for the reasons explained above, the use of at least one compound according to the invention takes place as a specific inhibitor of PDE5 in smooth muscle. In particular, the use according to the invention is characterized in that the smooth muscle is a vascular muscle and / or a pulmonary muscle. According to another aspect, the use according to the invention is characterized in that the compound or compounds are used at concentrations which do not act on the PDE5 of the platelets. The subject of the present invention is also the use for obtaining a medicament comprising as active principle at least one compound of general formula I to VI according to the invention for the preventive or curative treatment of a disease requiring selective PDE5 inhibition of smooth muscle. The use according to the invention can be characterized in that the medicament is intended for the preventive or curative treatment of hypertension, for the preventive or curative treatment of hypertension pulmonary, preventive or curative treatment of renal failure and / or preventive or curative treatment of male sexual impotence.

The present invention also relates to a pharmaceutical composition characterized in that it comprises, as active principle, at least one compound of general formula included among the formulas I to VI previously defined.

Thanks to said compounds of the present invention, it also becomes possible to provide a method of treatment or prevention of a disease in a mammal, in particular diseases requiring a specific selective action on the PDE5 of smooth muscle.

Said method of treatment or prevention comprises the administration to said mammal of a therapeutically effective amount of at least one compound of general formula I to VI or of a pharmaceutically acceptable derivative (salt, ester ...) of said compound according to the present invention.

Of course, the invention is not limited to the embodiment described. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without thereby departing from the scope of protection of the invention.

Claims

1. Compounds of general formulas I to VI

in which :

R ¹ , R ² , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹³ , R ¹⁹ , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ which may be the same or different, represent a proton, an alkyl group, an alkyl group substituted by one or more halogen atoms, an acyl group, an acyl group substituted by one or more halogen atoms, a hydrocarbon group having one or more ethylenic bonds, an aralkyl group, an aryl group, a group hydrocarbon which may be unsaturated and / or contain one or more heteroatoms;

R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ which may be identical or different, represent a proton, OR ⁸ , NR ⁹ R ¹⁰ , X ^ OaR ¹¹ , X ² SO ₂ (X ³ R ¹² ), SO _n R ¹³ , SO ₂ (NR ¹⁴ R ¹⁵ ), X ⁴ P (Y ¹ ) (X ⁵ R ¹⁶ ) (X ⁶ R ¹⁷ ), X ⁷ P (Y ² ) (X ⁸ R ¹⁸ ) R ¹⁹ ,

> 20 rl0τ, 2 rl l ₁ -, 22 _λ -n23> 24τ 25

P (Y ³ ) (X ⁹ R ^zυ ) (X ^ιυ R ^zl ), P (Y ⁴ ) (XR) R ^Z 'and P (Y ^J ) R ^Z4 R ³ , n can be equal to 0, 1 or 2 ; - R ¹² , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ R ²⁰ , R ²¹ and R ²² which may be the same or different, represent a proton, an alkyl group, an alkyl group substituted by one or more atoms halogen, a hydrocarbon group having one or more ethylenic bonds, an aralkyl group, an aryl group, a hydrocarbon group which may be unsaturated and / or contain one or more heteroatoms, an ammonium group, an ion of formula M ⁺ _{1 v} , in which M represents a metal and v is the valence state of the metal M, or an internal cation;

- X ¹ to X ¹¹ which may be identical or different, represent O, S or

NR 24

- Y ¹ to Y ⁵ which may be identical or different, represent O, S or

if,

and in which:

- if R ¹ and R ² are protons, R ⁶ is different from SO ₂ R ¹³ , SO ₂ (NR ¹⁴ R ¹⁵ );

- if 3 groups among R ³ R ⁴ , R ⁵ , R ⁶ and R ⁷ are protons, the other 2 cannot be OR ⁸ ;

- if R ³ is a methoxy or "-propyloxy group and if R ⁴ , R ⁵ and R ⁷ are protons, the group R ⁶ cannot contain the carbonyl-α, β-unsaturated unit, cannot be NH ₂ , a urea or thiourea.

2. Compounds according to claim 1, in which: - R ¹ , R ² , R ⁴ , R ⁵ , and R ⁷ are hydrogen atoms,

- R is the w-propyloxy group, and

- R ⁶ is the group NHC (O) CH ₂ OCH ₂ CH ₂ OBn

Bn representing a benzyl group (-CH ₂ C ₆ H ₅ ).

3. Use of at least one compound according to any one of claims 1 or 2 as a specific inhibitor of

PDE5 in smooth muscle.

4. Use according to claim 3, characterized in that the smooth muscle is a vascular muscle.

5. Use according to claim 3, characterized in that the smooth muscle is a pulmonary muscle.

6. Use according to any one of claims 3 to 5, characterized in that the compound (s) are used at concentrations which do not act on the PDE5 of the platelets.

7. Use for obtaining a medicament comprising as active principle at least one compound of general formula I to VI according to any one of claims 1 or 2 for the preventive or curative treatment of a disease requiring selective inhibition of PDE5 of smooth muscle.

8. Use according to claim 7, characterized in that the medicament is intended for the preventive or curative treatment of arterial hypertension.

9. Use according to claim 7, characterized in that the medicament is intended for the preventive or curative treatment of pulmonary hypertension.

10. Use according to claim 7, characterized in that the medicament is intended for the preventive or curative treatment of renal failure.

11. Use according to claim 7, characterized in that the medicament is intended for the preventive or curative treatment of male sexual impotence.

12. Pharmaceutical composition, characterized in that it comprises, as active principle, at least one compound of general formula included among formulas I to VI according to any one of claims 1 or 2.