WO2008031788A1 - Aminoazepine derivatives as highly efficient inhibitors of the inducible nitric oxide synthase - Google Patents

Abstract

The compounds of formula (I) wherein X represents a halogen atom, the stereoisomers thereof and the salts of the compounds and the stereoisomers thereof are effective inhibitors of the inducible nitric oxide synthase.

Description

AMINOAZEPINE DERIVATIVES AS HIGHLY EFFICIENT INHIBITORS OF THE INDUCIBLE NITRIC OXIDE SYNTHASE

Field of application of the invention

The invention relates to 4,5,6,7-tetrahydro-3H-azepin-2-ylamine compounds, a process for their preparation and the use thereof in the manufacture of pharmaceutical compositions.

Known technical background

WO 03/80607 describes imidazo[4,5-b]pyridine derivatives as inhibitors of the inducible nitric oxide synthase (iNOS). WO 96/33175 discloses cyclic amidino agents which are said to be useful as nitric oxide synthase (NOS) inhibitors. WO 2004/076451 relates to imidazo[4,5-b]quinoline derivatives and their use as NOS inhibitors. WO 02/10139 describes hexahydro-7-1 H-azepin-2-yl-hexanoic acid derivatives as iNOS inhibitors.

Description of the invention

It has now been found that the 4,5,6,7-tetrahydro-3H-azepin-2-ylamine compounds, which are described in detail below, have surprising and advantageous properties.

The invention relates to compounds of formula (I)

wherein X represents a halogen atom, stereoisomers thereof and salts of the compounds and stereoisomers thereof.

In a first preferred embodiment, the invention relates to compounds of formula (Ia)

wherein X represents a halogen atom, and salts thereof.

In a second preferred embodiment, the invention relates to compounds of formula (Ib)

wherein X represents a halogen atom, and salts thereof.

The halogen atom is selected from a fluorine (F), chlorine (Cl), bromine (Br) and iodine (I) atom.

In a further preferred embodiment, X is a Br atom or an I atom in the compounds of formulas (I), (Ia) and (Ib) and the salts thereof. Especially preferred are compounds of formulas (I), (Ia) and (Ib) and the salts thereof, wherein X is a Br atom.

Salts of the compounds according to the invention include all inorganic and organic acid addition salts and salts with bases, especially all pharmaceutically acceptable inorganic and organic acid addition salts and salts with bases, particularly all pharmaceutically acceptable inorganic and organic acid addition salts and salts with bases customarily used in pharmacy.

Examples of acid addition salts include, but are not limited to, hydrochlorides, hydrobromides, phosphates, nitrates, sulfates, acetates, citrates, D-gluconates, benzoates, 2-(4-hydroxybenzoyl)- benzoates, butyrates, subsalicylates, maleates, laurates, malates, fumarates, succinates, oxalates, tartarates, stearates, toluenesulfonates, methanesulfonates and 3-hydroxy-2-naphthoates. Of these, hydrochlorides are preferred. Examples of salts with bases include, but are not limited to, lithium, sodium, potassium, calcium, aluminum, magnesium, titanium, ammonium, meglumine and guanidinium salts. Of these, sodium and magnesium salts are preferred.

The salts include water-insoluble and, particularly, water-soluble salts.

The compounds of the invention and the salts thereof may contain, e.g. when isolated in crystalline form, varying amounts of solvents. Included within the scope of the invention are, therefore, all solvates of the compounds of formula (I), (Ia) and (Ib) and the salts thereof. Hydrates are a preferred example of said solvates.

The invention further includes the N-oxides of the compounds of formula (I), (Ia) and (Ib) and their salts. In particular, compounds represented by formula (Ic), (Id), (Ie), (If), (Ig) or (Ih) and their salts are included:

O - A -

The compounds of formula (I) contain a stereogenic center at the 7-position of the 4,5,6,7-tetrahydro- 3H-azepine ring:

The stereogenic center may have the absolute configuration R or the absolute configuration S (according to the rules of Cahn, lngold and Prelog). In the compounds of formula (Ia), the stereogenic center has the absolute configuration S. In compounds of formula (Ib), the stereogenic center has the absolute configuration R.

The compounds of formula (I) include the pure R stereoisomers, the pure S stereoisomers and all mixtures of these stereoisomers independent of the ratio, including the racemates. A "pure stereoisomer" is to be understood as containing not more than 5 wt.% of the other stereoisomer, preferably not more than 3 wt.% and more preferably not more than 1 wt.% of other stereoisomer.

As is apparent to a person skilled in the art, the compounds according to the invention can exist, with regard to the fused imidazo ring, in different tautomeric forms such as the 1-H form and the 3-H form, the 3-H form being shown in formula (I). The invention includes all conceivable tautomers in pure form as well as in any mixing ratio. In particular, the invention includes the pure 1-H-tautomers, the pure 3- H-tautomers and all mixtures thereof in any mixing ratio. A "pure tautomer" is to be understood as containing not more than 5 wt.% of other tautomers, preferably not more than 3 wt.% and more preferably not more than 1 wt.% of other tautomers.

As is additionally apparent to a person skilled in the art, the compounds according to the invention can exist, with regard to the cyclic amidine structure in the 4,5,6,7-tetrahydro-3H-azepin-2-ylamine moiety, in different tautomeric forms such as the exocyclic amine form, which is shown in formula (I) and the exocyclic imine form, which is shown in formula (Ik) below. The invention includes all conceivable tautomers in pure form as well as in any mixing ratio. In particular, the invention includes the pure exocyclic imine-tautomers, the pure exocyclic amine-tautomers and all mixtures thereof in any mixing ratio. As stated above, a "pure tautomer" is to be understood as containing not more than 5 wt.% of other tautomers, preferably not more than 3 wt.% and more preferably not more than 1 wt.% of other tautomers.

In the presence of water, the compounds according to the invention may have a cationic structure:

Some of the compounds and salts according to the invention may exist in different crystalline forms (polymorphs) which are within the scope of the invention.

Furthermore, derivatives of the compounds of formula (I), (Ia) and (Ib) and the salts thereof which are converted into compound (I), (Ia), (Ib) or a salt thereof in a biological system (bioprecursors or prodrugs) are covered by the invention. Said biological system is e.g. a mammalian organism, particularly a human subject. The bioprecursor is, for example, converted into the compound of formula (I), (Ia), (Ib) or a salt thereof by metabolic processes.

The invention further relates to compounds of formula (II) shown below, which are intermediates in the process of producing the compounds of formula (I) according to the invention as described hereinafter,

wherein X represents a halogen atom. As is apparent to a person skilled in the art, the compounds of formula (II) can exist in different tautomeric forms, in particular in the 1-H form, the 3-H form and in forms (II) and (Ma) shown below:

The invention includes all conceivable tautomers in pure form as well as in any mixing ratio. In particular, the invention includes the pure 1-H-tautomers, the pure 3-H-tautomers, the pure tautomers represented by formula (II), the pure tautomers represented by formula (Na) and all mixtures thereof in any mixing ratio. In this respect, a "pure tautomer" is to be understood as containing not more than 5 wt. % of other tautomers, preferably not more than 3 wt.% and more preferably not more than 1 wt.% of other tautomers.

The compounds according to the invention can be prepared as shown in the following reaction schemes 1 to 4.

Reaction scheme 1 :

In particular, compound (II) can be prepared by reacting compound (III) with Lawesson's reagent (2,4- bis(4-methoxyphenyl)-1 ,3-dithia-2,4-diphosphetane-2,4-disulfide) in an organic solvent (e.g. toluene or dioxane) at elevated temperature (e.g. 50 to 15O⁰C). Compound (I) can be obtained by reacting compound (II) with ammonia in an organic solvent (e.g. methanol) at room temperature or elevated temperature (e.g. 20 to 8O⁰C). Reaction scheme 2:

Compound (III) can be prepared by hydrogenating compound (IV) in the presence of a suitable catalyst, e.g. Adam's catalyst (platinum dioxide) or sulfided platinum on charcoal, preferably PtO₂, in an organic solvent, e.g. a lower alcohol, such as methanol, optionally in the presence of an acid, e.g. trifluoroacetic acid or acetic acid, at a temperature of from 20 to 6O⁰C, preferably at room temperature (20 to 25⁰C), according to procedures known to a person skilled in the art.

Reaction scheme 3:

a) b)

Compound (IV) can be obtained by a Wittig reaction, which is known to a person skilled in the art, of compounds (V) and (Vl). In particular, in a first step a) compound (V) (which can be synthesized e.g. according to WO 2005/061496) can be reacted with sodium hydride in an organic solvent, e.g. an ether such as tetrahydrofuran, at elevated temperature, e.g. 80 to 100⁰C; and in a second step b) compound (Vl) can be reacted with triacetoxy periodinane (Dess-Martin reagent) in an organic solvent, e.g. an ether such as tetrahydrofuran, at a temperature of from 20 to 4O⁰C, preferably at room temperature (20 to 25⁰C). Thereafter, the neutralized reaction mixture of step b) can be reacted with the reaction mixture of a) at elevated temperature, e.g. 80 to 100⁰C to obtain compound (IV).

In compound (IV) obtained by the Wittig reaction, the exocyclic double bond can have a Z- configuration or an E-configuration. In particular, a mixture of a compound, wherein the double bond has Z-config u ration, and a compound, wherein the double bond has E-configuration, can be obtained as reaction product.

Reaction scheme 4

(VII) (Vl)

Compound (VII) can be prepared as shown in reaction scheme 4 according to known procedures, e.g. as described by L. Benati et al., J. Org. Chem. 1999, 64(21 ), 7836-7841 and L. Benati et al., J. Org. Chem. 1999, 64(14), 5132-5138 from commercially available compound (IX) via compound (VIII).

Compound (Vl) can be synthesized from compound (VII), which is preferably dissolved in an organic solvent (e.g. dichloromethane), and lithium boron hydride dissolved in an organic solvent (e.g. tetrahydrofuran) at room temperature (20 to 25⁰C) according to procedures known to a person skilled in the art.

It is known to the person skilled in the art that, if there are a number of reactive centers on a starting or intermediate compound, it may be necessary to block one or more reactive centers temporarily by protective groups in order to allow a reaction to proceed specifically at the desired reaction center. A detailed description for the use of a large number of proven protective groups is found, for example, in T. W. Greene, Protective Groups in Organic Synthesis, John Wiley & Sons, 1999, 3rd Ed., or in P. Kocienski, Protecting Groups, Thieme Medical Publishers, 2000.

The compounds according to the invention are isolated and purified in a manner known per se, e.g. by distilling off the solvent in vacuo and recrystallizing the residue obtained from a suitable solvent or subjecting it to one of the customary purification methods, such as column chromatography on a suitable support material.

Salts of the compounds according to the invention can be obtained by dissolving the free compound in a suitable solvent (for example a ketone such as acetone, methylethylketone or methylisobutylketone, an ether such as diethyl ether, tetrahydrofuran or dioxane, a chlorinated hydrocarbon such as methylene chloride or chloroform, or a low molecular weight aliphatic alcohol such as methanol, ethanol or isopropanol) which contains the desired acid or base, or to which the desired acid or base is then added. The acid or base can be employed in salt preparation, depending on whether a mono- or polybasic acid or base is concerned and depending on which salt is desired, in an equimolar quantitative ratio or one differing therefrom. The salts are obtained by filtering, reprecipitating, precipitating with a non-solvent for the salt or by evaporating the solvent. Salts obtained can be converted into the free compounds which, in turn, can be converted into salts. In this manner, pharmaceutically unacceptable salts, which can be obtained, for example, as process products in the manufacturing on an industrial scale, can be converted into pharmaceutically acceptable salts by processes known to the person skilled in the art.

The compounds according to the invention can be converted into their N-oxides of formulas (Id), (If) and (Ih), for example, with the aid of hydrogen peroxide in methanol, optionally in the presence of ReO₃, or with the aid of m-chloroperoxybenzoic acid in dichloromethane or, preferably, acetic acid. The compounds according to the invention can be converted into their N-oxides of formulas (Ic), (Ie) and (Ig), for example, by reaction with hydroxylamine hydrochloride in methanol. The person skilled in the art is familiar with the reaction conditions for carrying out the N-oxidation reactions.

The enantiomers of formulas (Ia) and (Ib) and the salts thereof can be obtained e.g. by asymmetric synthesis, by using chiral starting compounds in synthesis and by splitting up enantiomeric mixtures obtained in synthesis. An example for a synthesis using chiral starting compounds is shown in following reaction schemes 5 to 7: Reaction scheme 5

The synthesis of compound (XII) from compound (X) via compound (Xl) is described e.g. in G. F.

Busscher et al., Tetrahedron Lett. 2004, 45, 3629-3632. Compound (X) can be obtained, for example, as described in F.P.J.T. Rutjes et al., Eur. J. Org. Chem. 1999, 1127-1135.

Compound (XIV) can be prepared from compound (XII) via compound (XIII) as described e.g. in F.P.J.T. Rujes et al., Tetrahedron Lett. 1997, 38(4), 677-680.

Reaction scheme 6

Compound (XV) may, for example, be prepared from compound (XIV) by hydrogenation using a suitable catalyst, e.g. palladium on carbon, in an organic solvent, e.g. ethanol, preferably at room temperature (20 to 25⁰C). Compound (XVI) can be obtained by reacting compound (XV) with lithium boron hydride in an organic solvent, e.g. dichloromethane or tetrahydrofuran, preferably at room temperature (20 to 25⁰C). Compound (XVII) is e.g. synthesized from compound (XVI) by using A- methoxy-2,2,6,6-tetramethylpiperidyl-1-oxyl or analogs, e.g. 2,2,6,6-tetramethylpiperidyl-1-oxyl, an alkali halogenide (e.g. potassium bromide), a suitable oxidizing agent, for example sodium hypochlorite, and optionally NaHCO₃, in a two-phase solvent system containing an organic solvent, e.g. toluene and/or ethyl acetate, and water, preferably at 0 to 2O⁰C. Reacting compound (XVII) with compound (V) in the presence of a suitable base, e.g. sodium hydride, potassium tert-butoxide or an alkali bis(trimethylsilyl)amide, preferably sodium hydride, in an organic solvent, e.g. tetrahydrofuran and/or dioxane, preferably at elevated temperature, e.g. 30 to 6O⁰C, and subsequent hydrogenation in the presence of a suitable catalyst, e.g. platinum dioxide, in an organic solvent (e.g. an alcohol, such as methanol) gives compound (XVIII). Reaction scheme 7

Compound (XIX) can be prepared by converting compound (XVIII) to a hydrochloride intermediate, which is subsequently reacted with (NH₄)₂Ce(Nθ₃)₆ in an organic solvent, e.g. acetonitrile, containing hydrochloric acid, preferably at 0 to 2O⁰C. Compound (XX) can be synthesized by reacting compound (XIX) with Lawesson's reagent (2,4-bis(4-methoxyphenyl)-1 ,3-dithia-2,4-diphosphetane-2,4-disulfide) in an organic solvent, e.g. toluene or dioxane, at elevated temperature, e.g. 50 to 15O⁰C. Compound (Ib) can be obtained by reacting compound (XX) with ammonia in an organic solvent, e.g. methanol, at room temperature or elevated temperature, e.g. 20 to 8O⁰C.

Enantiomeric mixtures can be split up into the pure enantiomers by methods known to a person skilled in the art. Preferably, enantiomeric mixtures can be separated e.g. by forming diastereomers with a chiral auxiliary agent, resolving the diastereomers obtained and removing the chiral auxiliary agent. As chiral auxiliary agents, for example, chiral acids, e.g. chiral sulfonic acids, can be used to separate enantiomeric bases and chiral bases can be used to separate enantiomeric acids via formation of diastereomeric salts. Furthermore, diastereomeric derivatives such as diastereomeric esters can be formed from enantiomeric mixtures of alcohols or enantiomeric mixtures of acids, respectively, using chiral acids or chiral alcohols, respectively, as chiral auxiliary agents. Additionally, diastereomeric complexes or diastereomeric clathrates may be used for separating enantiomeric mixtures. Preferably, enantiomeric mixtures can be split up using chiral separating columns in chromatography. Another suitable method for the isolation of enantiomers is the enzymatic separation. As will be appreciated by persons skilled in the art, the invention is not limited to the particular embodiments described herein, but covers all modifications of said embodiments that are within the spirit and scope of the invention as defined by the appended claims.

All patents, patent applications, publications, test methods and other materials cited herein are incorporated by reference in their entireties.

The following examples illustrate the invention in greater detail, without restricting it. Further compounds according to the invention, of which the preparation is not explicitly described, can be prepared in an analogous way.

The compounds which are mentioned as final products in the examples, stereoisomers thereof and salts of the compounds and stereoisomers thereof represent preferred embodiments of the invention.

Examples

The following abbreviations are used: m.p.: melting point, h: hours, min: minutes, TLC: thin layer chromatography, Rf: retention factor, t_r: retention time, ee: enatiomeric excess, M: molecular ion, ESI- MS: electrospray ionization mass spectrometry, Lawesson's reagent: 2,4-bis(4-methoxyphenyl)-1 ,3- dithia-2,4-diphosphetane-2,4-disulfide, 4-Methoxy-TEMPO: 4-Methoxy-2,2,6,6-tetramethylpiperidyl-1- oxyl. Other abbreviations have the meanings customary for the person skilled in the art.

LiChroprep-NH₂ ^® HPTLC is available from Merck KGaA (Darmstadt, Germany). CHIRALPAK^® AD-H 5μm column (250 x 20 mm) is available from Daicel Chemical Industries, Ltd. Percentages given for molecular ion peaks in the ESI-MS refer to the intensity of each signal due to a halogen isotope ratio.

Final products

1. 7-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine

(racemate)

493 mg of 7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepane-2-thione (compound A1 ) are dissolved in 32 ml of methanol containing ammonia (strength: 7.0 M) and heated at 5O⁰C for 72 hours. Subsequently, the reaction mixture is cooled in an ice bath for 40 min, during which time a colorless precipitate is formed. The precipitate is filtered with suction and dried in high vacuum to yield 263 mg of the title compound as an amorphous, colorless solid of m.p. 224⁰C (decomposition). ESI-MS: 336.3/338.3 (MH+). TLC: Rf = 0.60 (LiChroprep-NH₂® HPTLC, methanol/water 10:1 parts by volume).

2. (7S)-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine

450 mg of 7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine (compound 1 ) are separated on a CHIRALPAK^® AD-H 5μm column (250 x 20 mm) [eluent: 80 vol.% carbon dioxide / 20 vol.% (methanol containing 1.0 vol.% diethylamine), retention time t_r = 5.47 min] at 15 MPa to yield 144 mg of the enatiomerically pure title compound after reprecipitation from methanol. M.p. 229⁰C (decomp.), ESI-MS: 336.3/338.3 (MH⁺), TLC: Rf = 0.60 (LiChroprep-NH₂ ^® HPTLC, methanol/water 10:1 parts by volume), enatiomeric purity: > 98 % ee, amount of rotation: [α]_D = + 17°.

3. (7R)-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine

A) Racemate resolution is achieved as described for (7S)-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)- ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine (compound 2) to yield 110 mg of the enatiomerically pure title compound after reprecipitation from methanol. t_r = 8.05 min, m.p. 227 ⁰C (decomp.), ESI-MS: 336.3/338.3 (MH⁺), TLC: Rf = 0.60 (LiChroprep-NH₂ ^® HPTLC, methanol/water 10:1 parts by volume), enatiomeric purity: > 98 % ee, amount of rotation: [α]_D = - 18°.

B) 34 mg of (R)-7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepane-2-thione (compound A2) are dissolved in 2.3 ml of methanol containing ammonia (strength: 7.0 M) and heated at 5O⁰C for 72 hours. Subsequently, the reaction mixture is evaporated to dryness. The remaining residue is purified by flash chromatography on LiChroprep-NH₂ ^® HPTLC (eluent: neat ethanol) to afford 12 mg of the title compound.

Starting materials

A1. 7-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepane-2-thione

670 mg of 7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepan-2-one (compound B1 ) are suspended in 65 ml of toluene under an atmosphere of dry nitrogen. Subsequently, 844 mg of Lawesson's reagent are added and the solution is heated at 100⁰C for 18 hours. Thereafter, the reaction mixture is evaporated to dryness to yield approximately 1.7 g of crude material, which is purified by flash chromatography (eluent gradient: dichloromethane / 0-5.0 vol.% ethanol) to afford 700 mg of the title compound as an amorphous, light yellow solid. ESI-MS: 353.1/355.1 (MH+). TLC: Rf = 0.59 (dichloromethane/ethanol 10:1 parts by volume).

A2. (R)-7-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepane-2-thione

The title compound is synthesized as described for 7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]- azepane-2-thione (compound A1 ) from 17 mg of (R)-7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)- ethyl]-azepane-2-one (compound B2) and 40 mg of Lawesson's reagent in 5.0 ml oxygen-free dioxane to yield 40 mg of the title compound as an amorphous, colorless solid of m.p. 216⁰C (decomp.). ESI- MS: 353.1/355.1 (MH⁺). TLC: Rf = 0.59 (dichloromethane/ethanol 10:1 parts by volume).

B1. 7-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepan-2-one

665 mg of 7-[(E)-2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-vinyl]-3,4,5,6-tetrahydro-azepin-2-one (compound C1 ) are dissolved in 50 ml of methanol. Subsequently, 91 mg of Adam's catalyst (PtO₂) is added and the suspension is vigorously stirred under an atmosphere of hydrogen at room temperature for 70 h. Thereafter, the reaction mixture is evaporated to dryness, purified by flash chromatography (eluent gradient: dichloromethane / 0-10 vol.% ethanol), and lyophilized from 4.0 ml of water, 4.0 ml of dioxane, and 1.0 ml of ethanol to afford 236 mg of the title compound as an amorphous, colorless solid. M. p. 245⁰C. ESI-MS: 337.2/339.1 (MH⁺). TLC: Rf = 0.47 (dichloromethane/ethanol 10:1 parts by volume).

B2. (R)-7-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepane-2-one

100 mg of (R)-7-[2-(6-bromo-3H-innidazo[4,5-b]pyridin-2-yl)-ethyl]-1-(4-nnethoxy-benzyl)-azepan-2- one (compound C2) are dissolved in 28 ml of dry acetonitrile. After cooling the solution in an ice bath, 217 μl of hydrogen chloride in diethyl ether (strength 1.0 M) are added and the reaction mixture is allowed to warm up to room temperature. After 30 min, the solution is evaporated to dryness to afford 107 mg of (R)-7-[2-(6-bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-azepan-2-one hydrochloride intermediate, which is subsequently dissolved in 30 ml of a mixture of hydrochloric acid (strength 3.0 M) and acetonitrile (3:7 parts by volume). After cooling the reaction mixture in an ice bath, a solution of 1 19 mg of (NH₄)₂Ce(Nθ₃)₆ in 17 ml of the hydrochloric acid/acetonitrile mixture is added dropwise (20 min). After further 30 min, additional 179 mg of eerie ammonium nitrate are added in portions. After 30 min, the reaction mixture is quenched using saturated NaHCO₃ solution. Acetonitrile is removed in vacuo from the suspension and the remaining aqueous layer is extracted with 300 ml of dichloromethane. The organic layer is separated, dried using Na₂SO₄, filtered with suction, and evaporated to dryness to yield 102 mg of a crude material which is purified by flash chromatography (eluent gradient: dichloromethane / 10-20 vol.% ethanol) to afford 42 mg of the title compound as a waxy solid. ESI-MS: 337.1/339.1 (MH⁺). TLC: Rf = 0.23 (dichloromethane/ethanol 10:1 parts by volume).

C1. 7-[(E)-2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-vinyl]-3,4,5,6-tetrahydro-azepin-2-one

a) 503 mg of sodium hydride (strength 60 wt.% dispersion in mineral oil) are suspended in 90 ml of tetrahydrofuran under an atmosphere of dry nitrogen. Subsequently, a suspension of 4.23 g of (6- bromo-3H-imidazo[4,5-b]pyridin-2-ylmethyl)-tributyl-phosphonium chloride (compound D3) in 90 ml of tetrahydrofuran is added in the course of 5 min. Thereafter, the suspension is heated to 9O⁰C for 1 hour. b) 1.70 g of 7-hydroxymethyl-azepan-2-on (compound D1 ) are dissolved in 180 ml of tetrahydrofuran under an atmosphere of dry nitrogen. Subsequently, 4.44 g of triacetoxy periodinane (Dess-Martin reagent) are added at room temperature and stirring is continued for further 3 hours. Thereafter, the suspension is carefully neutralized using sodium hydride (strength 60 wt.% dispersion in mineral oil) and added dropwise to the reaction mixture of a) at 9O⁰C during 20 min. Stirring at 9O⁰C is continued for 17 h. Subsequently, the suspension is evaporated to dryness and purified by flash chromatography (eluent gradient: dichloromethane / 0-10 vol.% ethanol) to afford 809 mg of the title compound as an oil. ESI-MS: 333.2/335.2 (MH⁺). TLC: Rf = 0.44 (dichloromethane/ethanol 10: 1 parts by volume).

C2. (R)-7-[2-(6-Bromo-3H-imidazo[4,5-b]pyridin-2-yl)-ethyl]-1-(4-methoxy-benzyl)-azepane-2- one 46 mg of sodium hydride (strength 60 wt.% dispersion in mineral oil) are suspended in 4.0 ml of tetrahydrofuran and 4.0 ml of dioxane under an atmosphere of dry nitrogen. Subsequently, a solution of 515 mg of (6-bromo-3H-imidazo[4,5-b]pyridin-2-ylmethyl)-tributyl-phosphonium chloride (compound D3) in 3.0 ml of tetrahydrofuran/dioxane (1 :1 parts by volume) is added. Thereafter, the suspension is heated to 4O⁰C for 1 hour. Then, a solution of 300 mg of (R)-1-(4-methoxy-benzyl)-7-oxo-azepane-2- carbaldehyde (compound D2) in 2.0 ml of tetrahydrofuran/dioxane (1 :1 parts by volume) is added dropwise at 4O⁰C and the reaction mixture is stirred for 48 hours. Subsequently, the reaction mixture is evaporated to dryness to afford 920 mg of crude material. Unreacted aldehyde, not tri-n- butylphosphine oxide can be separated by flash chromatography using eluent gradient dichloromethane / 0-10 vol.% ethanol to afford 630 mg of crude E/Z-configu rated intermediate as a yellowish oil. The intermediate is dissolved in 60 ml of methanol. Subsequently, 64 mg of Adam's catalyst (PtO₂) is added and the suspension is vigorously stirred at room temperature under an atmosphere of hydrogen at standard pressure for 24 hours. The mixture is filtered with suction through kieselguhr and rinsed with methanol. The filtrate is evaporated to dryness to yield 608 mg of the crude title product. Purification by flash chromatography (eluent gradient: dichloromethane / 0-10 vol.% ethanol) affords 35 mg of the title compound as a waxy solid. ESI-MS: 457.0/459.1 (MH⁺). TLC: Rf = 0.21(dichloromethane/ethanol 20:1 parts by volume).

D1. 7-Hydroxymethyl-azepan-2-on

3.10 g of 7-oxo-azepane-2-carboxylic acid ethyl ester (compound E1 ) are dissolved in 150 ml of dichloromethane under a nitrogen atmosphere. At room temperature 8.45 ml of lithium boron hydride solution in tetrahydrofuran (strength 2.0 M) are slowly added to the solution in the course of 10 min. Thereafter, the reaction mixture is stirred for 17 hours overnight at room temperature. Subsequently, the mixture is cooled in an ice bath and acidified to pH 1 using hydrochloric acid (strength 3.0 M). Under stirring, the reaction mixture is allowed to warm up to room temperature. Thereafter, potassium carbonate is carefully added thereby re-adjusting neutral pH. The reaction mixture is filtered with suction and the filtrate is concentrated in vacuo. Purification is achieved by flash chromatography (eluent gradient: dichloromethane / 0-10 vol.% ethanol) to yield 1.46 g of the title compound as colorless white solid. M. p. 100°C. ESI-MS: 144.1 (MH⁺). TLC: Rf = 0.47 (dichloromethane/ethanol 10:1 parts by volume; iodine staining).

D2. (R)-1-(4-Methoxy-benzyl)-7-oxo-azepane-2-carbaldehyde

1.86 g of (R)-7-hydroxymethyl-1-(4-methoxy-benzyl)-azepan-2-one (compound E2) is dissolved in 20 ml of toluene and 20 ml of ethyl acetate. Subsequently, 3.0 ml of water, 26 mg of 4-methoxy-TEMPO, and 840 mg of potassium bromide are added. The vigorously stirred, clear solution is cooled in an ice bath and 30 ml of a freshly prepared solution of sodium hypochlorite made from 9.61 ml of commercially available NaOCI solution (strength 10-13% active chlorine; no older than 3 months), 19.90 ml of water, and 1.23 g of NaHCO₃ is added dropwise, thereby waiting until the resulting yellow- brownish color caused by each drop has disappeared. After completion of the oxidation (3 hours, TLC monitoring dichloromethane/ethanol 20:1 parts by volume) the aqueous and organic layer are separated. The aqueous layer is extracted once with 100 ml of ethyl acetate. The combined organic layers are washed twice using 50 ml each of Na₂S₂O₃ solution (strength 10 wt.%), dried using Na₂SO₄, filtered with suction, and concentrated in vacuo to afford 1.51 g of crude material. Purification by flash chromatography (eluent gradient: cyclohexane / 25-50 vol.% ethyl acetate) yields 1.13 g of the title compound as a colorless oil. ESI-MS: 262.1 (MH⁺). TLC: Rf = 0.15 (cyclohexane/ethyl acetate 2:1 parts by volume).

D3. (6-Bromo-3H-imidazo[4,5-b]pyridin-2-ylmethyl)-tributyl-phosphonium chloride

The title compound is synthesized as disclosed in WO 2005/061496.

E1. 7-Oxo-azepane-2-carboxylic acid ethyl ester

The title compound is synthesized from compound F1 according to a procedure described by L. Benati et al., J. Org. Chem. 1999, 64(21 ), 7836-7841.

E2. (R)-7-Hydroxymethyl-1-(4-methoxy-benzyl)-azepane-2-one

3.26 g of (R)-1-(4-methoxy-benzyl)-7-oxo-azepane-2-carboxylic acid methyl ester (compound F2) was dissolved in 150 ml of dichloromethane. Subsequently, 14.0 ml of lithium boron hydride in tetrahydrofuran (strength 2.0 M) are added dropwise. The reaction mixture is stirred at room temperature overnight for 18 hours (TLC monitoring dichloromethane/ethanol 20:1 parts by volume). Thereafter, the mixture is cooled in an ice bath and adjusted to pH 3 using hydrochloric acid (strength 2.0 M). Subsequently, 30 ml of methanol are added and the solution is neutralized using potassium carbonate. Thereafter, the mixture is filtered with suction and evaporated to dryness. The residue is re- dissolved in 200 ml of dichloromethane and extracted with 100 ml of half -saturated brine (aqueous

NaCI solution). The organic layer is separated, dried using sodium sulfate, filtered, and concentrated in vacuo. The remaining residue is suspended in 100 ml of petrol ether and filtered with suction. The filter cake is dried under high vacuum to yield 2.69 g of the pure title compound as an amorphous, colorless solid of m.p. 124⁰C. ESI-MS: 264.0 (MH⁺). TLC: Rf = 0.33 (dichloromethane/ethanol 20:1 parts by volume).

F1. i-Azido-2-oxo-cyclohexanecarboxylic acid ethyl ester

The title compound is synthesized according to procedures described by L. Benati et al., J. Org. Chem. 1999, 64(21 ), 7836-7841 and L. Benati et al., J. Org. Chem. 1999, 64(14), 5132-5138. F2. (R)-1-(4-Methoxy-benzyl)-7-oxo-azepane-2-carboxylic acid methyl ester

3.40 g of (R^I-^-methoxy-benzyl^-oxo^S.ΘJ-tetrahydro-I H-azepine^-carboxylic acid methyl ester (compound G1 ) are dissolved in 350 ml of ethanol under an atmosphere of nitrogen. Subsequently, 340 mg of palladium on charcoal (strength 10 wt.%) are added. Nitrogen is replaced by a hydrogen gas flow and the reaction mixture is vigorously stirred for 2 hours at room temperature and standard pressure. Subsequently, the suspension is filtered with suction through kieselguhr, rinsed with ethanol, and evaporated to dryness to yield 9.90 g of the pure title compound as an oil. ESI-MS: 292.1 (MH⁺). TLC: Rf = 0.33 (cyclohexane/ethyl acetate 2:1 parts by volume).

G1. (R)-1-(4-Methoxy-benzyl)-7-oxo-2,3,6,7-tetrahydro-1 H-azepine-2-carboxylic acid methyl ester

1.96 g of (R)-2-[but-3-enoyl-(4-methoxy-benzyl)-amino]-pent-4-enoic acid methyl ester (compound H1 ) is dissolved in 200 ml of dry dichloromethane under an atmosphere of nitrogen. Subsequently, 77 mg of (1 ,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxyphenylmethylene)- ruthenium are added and the reaction mixture is stirred at 5O⁰C for 18 hours. Thereafter, the solution is extracted with 75 ml of half-saturated brine (aqueous NaCI solution). The organic layer is separated, dried using Na₂SO₄, filtered with suction, and evaporated to dryness to afford 1.92 g of crude material. Purification by flash chromatography (eluent gradient: cyclohexane / 20-50 vol.% ethyl acetate) to yield 1.39 g of the title compound as an oil. ESI-MS: 289.9 (MH⁺). TLC: Rf = 0.30 (cyclohexane/ethyl acetate 2:1 parts by volume).

H1. (R)-2-[But-3-enoyl-(4-methoxy-benzyl)-amino]-pent-4-enoic acid methyl ester

6.07 g of (R)-2-(4-methoxy-benzylamino)-pent-4-enoic acid methyl ester (compound J1 ) are dissolved in 200 ml of dichloromethane. Subsequently, 2.48 ml of vinyl acetic acid and a suspension of 8.36 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride in 56 ml of dichloromethane are added. The reaction mixture is stirred at room temperature for 20 hours. Thereafter, the mixture is extracted with 100 ml of half -saturated brine (aqueous NaCI solution). The organic layer is separated, dried using Na₂SO₄, filtered with suction, and evaporated to dryness to afford 7.82 of crude material which is purified by flash chromatography (eluent gradient: cyclohexane / 20-50 vol.% ethyl acetate) to yield 6.33 g of the title compound as an oil. ESI-MS: 317.9 (MH⁺), 340.1 (MNa⁺). TLC: Rf = 0.25 (cyclohexane/ethyl acetate 3:1 parts by volume).

J1. (R)-2-(4-Methoxy-benzylamino)-pent-4-enoic acid methyl ester

9.66 g of (R)-2-[(4-methoxy-benzylidene)-amino]-pent-4-enoic acid methyl ester (compound K1 ) are dissolved in 160 ml of methanol and cooled in an ice bath. Subsequently, 2.07 g of sodium boron hydride are added and the suspension is stirred for 1.5 hours at O⁰C. Thereafter, excess NaBH₄ is quenched using 10 ml of hydrochloric acid (strength 3.0 M), thereby adjusting pH 1. Subsequently, the reaction mixture is neutralized using saturated NaHCO₃ solution and evaporated to dryness. The remaining residue is taken up in 170 ml of dichloromethane and extracted with 30 ml of water. The organic layer is separated, dried using Na₂SO₄, filtered with suction, and concentrated in vacuo to yield 8.84 g of crude material. Purification by flash chromatography (eluent gradient: cyclohexane / 16- 50 vol.% ethyl acetate) affords 6.07 g of the title compound as an oil. ESI-MS: 250.0 (MH⁺). TLC: Rf = 0.38 (cyclohexane/ethyl acetate 3:1 parts by volume).

K1. (R)-2-[(4-Methoxy-benzylidene)-amino]-pent-4-enoic acid methyl ester

5.27 g of (R)-2-amino-pent-4-enoic acid methyl ester (compound L1 ) are dissolved in 50 ml of dichloromethane under an atmosphere of dry nitrogen. Subsequently, 20.4 ml of hydrogen chlorine in diethyl ether (strength 2.0 M) are added dropwise at room temperature. The reaction mixture is stirred for further 10 min. Thereafter, 5.23 ml of triethylamine are carefully added (build-up of smoke). Subsequently, 9.23 g of magnesium sulfate and 5.83 g of p-anisaldehyde are added. The reaction mixture is stirred overnight at room temperature for 18 hours. Then, the suspension is filtered with suction, concentrated in vacuo, and diluted with 330 ml of diethyl ether. The organic layer is extracted with 70 ml of saturated Na₂CO₃ solution, dried using MgSO₄, filtered with suction, and evaporated to dryness to yield 9.66 g of the title compound as an oil. ESI-MS: 248.1 (MH⁺). TLC: Rf = 0.90 (dichloromethane/ethanol 20:1 parts by volume; ninhydrin staining).

L1. (R)-2-Amino-pent-4-enoic acid methyl ester

The title compound is synthesized according to the procedure described by F.P.J.T. Rutjes et al., Eur. J. Org. Chem. 1999, 1 127-1135.

Commercial Utility

The compounds, stereoisomers thereof and pharmaceutically acceptable salts of the compounds and stereoisomers thereof according to the invention (hereinafter referred to as "compounds according to the invention") have valuable pharmaceutical properties which make them commercially utilizable. In particular, they are inhibitors of the enzyme inducible nitric oxide synthase.

Nitric oxide synthases (NO synthases, NOSs) are enzymes that generate NO and citrulline from the amino acid arginine. In certain pathophysiological situations, such as arginine depletion or tetrahydrobiopterin depletion, the generation of O₂ ^" from NO synthases instead or together with NO has been reported. NO is long known as a signalling molecule in most living organisms including mammals and humans. The most prominent action of NO is it's smooth muscle relaxing activity, which is caused on the molecular level by the activation of soluble guanylate cyclase. In the last years, numerous other enzymes have been shown to be regulated by NO or to be reaction products of NO.

There exist three isoforms of NO synthases which fall into two classes and differ in their physiologic functions and molecular properties. The first class, known as constitutive NO synthases, comprises of the endothelial NO synthase and the neuronal NO synthase. Both isoenzymes are expressed constitutively in various cell types, but are most prominent in endothelial cells of blood vessel walls (therefore called endothelial NO synthase, eNOS or NOS-III) and in neuronal cells (therefore called neuronal NO synthase, nNOS or NOS-I). Activation of these two enzymes is dependent on Ca²7calmodulin which is generated by transient increases of the intracellular free Ca²⁺ concentration. Activation of constitutive isoforms leads to transient bursts of nitric oxide resulting in nanomolar cellular or tissue NO concentrations. The endothelial isoform is involved in the physiologic regulation of blood pressure. NO generated by the neuronal isoform seems to have neurotransmitter function and the neuronal isoform is among other regulatory processes involved in memory function (e.g. long term potentiation).

In contrast to the constitutive isoforms, the activation of inducible NO synthase (iNOS, NOS-II), the sole member of the second class, is performed by transcriptional activation of the iNOS promoter. For example, proinflammatory stimuli lead to transcription of the gene for inducible NO synthase, which is catalytically active without increases in the intracellular Ca²⁺ concentration. Due to the long half life of the inducible NO synthase and the unregulated activity of the enzyme, high micromolar concentrations of NO are generated over longer time periods. These high NO concentrations alone or in cooperation with other reactive radicals such as O₂ ^' are cytotoxic. Therefore, in situations of microbial infections, iNOS is involved in cell killing by macrophages and other immune cells during early nonspecific immune responses.

There are a number of pathophysiological situations which among others are characterized by the high expression of inducible NO synthase and concomitant high NO or O₂ ^" concentrations. It has been shown that these high NO concentrations alone or in combination with other radical species lead to tissue and organ damage and are causally involved in these pathophysiologies. As inflammation is characterized by the expression of proinflammatory enzymes, including inducible NO synthase, selective inhibitors of inducible NO synthase can be used as therapeutics for diseases involving acute and chronic inflammatory processes. Other pathophysiologies with high NO production from inducible NO synthase are several forms of shock (e.g. septic, hemorrhagic and cytokine-induced shock).

It has been shown in in-vivo animal models of septic shock that reduction of circulating plasma NO levels by NO scavenger or inhibition of inducible NO synthase restores systemic blood pressure, reduces organ damage and increases survival (deAngelo Exp. Opin. Pharmacother. 19-29, 1999; Redl et al. Shock 8, Suppl. 51 , 1997; Strand et al. Crit. Care Med. 26, 1490-1499, 1998). It has also been shown that increased NO production during septic shock contributes to cardiac depression and myocardial dysfunction (Sun et al. J. MoI. Cell Cardiol. 30, 989-997, 1998). Furthermore there are also reports showing reduced infarct size after occlusion of the left anterior coronary artery in the presence of NO synthase inhibitors (Wang et al. Am. J. Hyperttens. 12, 174-182, 1999). Considerable inducible NO synthase activity is found in human cardiomyopathy and myocarditis, supporting the hypothesis that NO accounts at least in part for the dilatation and impaired contractility in these pathophysiologies (de Belder et al. Br. Heart. J. 4, 426-430, 1995).

In animal models of acute or chronic inflammation, blockade of inducible NO synthase by isoform- selective or nonselective inhibitors or genetic knock out improves therapeutic outcome. It is reported that experimental arthritis (Connor et al. Eur. J. Pharmacol. 273, 15-24, 1995) and osteoarthritis (Pelletier et al. Arthritis & Rheum. 41 , 1275-1286, 1998), experimental inflammations of the gastrointestinal tract (Zingarelli et al. Gut 45, 199-209, 1999), experimental glomerulonephritis (Narita et al. Lab. Invest. 72, 17-24, 1995), experimental diabetes (Corbett et al. PNAS 90, 8992-8995, 1993), and lipopolysaccharide-induced experimental lung injury is reduced by inhibition of inducible NO synthase or in iNOS knock out mice (Kristof et al. Am. J. Crit. Care. Med. 158, 1883-1889, 1998). A pathophysiological role of inducible NO synthase derived NO or O₂ ^" is also discussed in chronic inflammatory diseases, such as asthma, bronchitis and chronic obstructive pulmonary disease (COPD).

Furthermore, in models of neurodegenerative diseases of the central nervous system such as MPTP- induced parkinsonism (MPTP = 1-methyl-4-phenyl-1 ,2,3,6-tetrahydropyridine), amyloid peptide induced Alzheimer's disease (Ishii et al., FASEB J. 14, 1485-1489, 2000), malonate induced Huntington's disease (Connop et al. Neuropharmacol. 35, 459-465, 1996), experimental meningitis (Korytko & Boje Neuropharmacol. 35, 231-237, 1996) and experimental encephalitis (Parkinson et al. J. MoI. Med. 75, 174-186, 1997) a causal participation of NO and inducible NO synthase has been shown. lncreased iNOS expression has been found in the brains of AIDS (acquired immunodeficiency syndrome) patients and it is therefore assumed that iNOS plays a role in AIDS related dementia (Bagasra et al. J. Neurovirol. 3 153-167, 1997).

Other studies implicated nitric oxide as a potential mediator of microglia dependent primary demyelination, a hallmark of multiple sclerosis (Parkinson et al. J. MoI. Med. 75, 174-186, 1997).

An inflammatory reaction with concomitant expression of inducible NO synthase also takes place during cerebral ischemia and reperfusion (ladecola et al. Stroke 27, 1373-1380, 1996). Resulting NO together with O₂ ^' from infiltrating neutrophils is thought to be responsible for cellular and organ damage.

Also, in models of traumatic brain injury (Mesenge et al. J. Neurotrauma 13, 209-214, 1996; Wada et al. Neurosurgery 43, 1427-1436, 1998), NO synthase inhibitors have been shown to possess protective properties. A regulatory role for inducible NO synthase has been reported in various tumor cell lines (Tozer & Everett Clin Oncol. 9. 357-264, 1997).

On account of their inducible NO synthase inhibiting properties, the compounds according to the invention can be employed in human and veterinary medicine, where an excess of NO or O₂ due to increases in the activity of inducible NO synthase is involved. In particular, they can be used without limitation for the treatment and prophylaxis of the following diseases:

Acute inflammatory diseases: Septic shock, sepsis, systemic inflammatory response syndrome (SIRS), hemorrhagic shock, shock states induced by cytokine therapy (interleukin-2, tumor necrosis factor), organ transplantation and transplant rejection, head trauma, acute lung injury, acute respiratory distress syndrome (ARDS), inflammatory skin conditions such as sunburn, inflammatory eye conditions such as uveitis, glaucoma and conjunctivitis.

Chronic inflammatory diseases, in particular chronic inflammatory diseases of peripheral organs and the CNS: gastrointestinal inflammatory diseases such as Crohn's disease, inflammatory bowel disease, ulcerative colitis, lung inflammatory diseases such as asthma, chronic bronchitis, emphysema and COPD, inflammatory diseases of the upper respiratory tract such as allergic rhinitis and allergic sinusitis, inflammatory eye conditions such as allergic conjunctivitis, arthritic disorders such as rheumatoid arthritis, osteoarthritis and gouty arthritis, heart disorders such as cardiomyopathy and myocarditis, atherosclerosis, neurogenic inflammation, skin diseases such as psoriasis, dermatitis and eczema, diabetes, glomerulonephritis; dementias such as dementias of the Alzheimer's type, vascular dementia, dementia due to a general medical condition such as AIDS, Parkinson's disease, Huntington's induced dementias, amyotrophic lateral sclerosis (ALS), multiple sclerosis; necrotizing vasculitides such as polyarteritis nodosa, serum sickness, Wegener's granulomatosis, Kawasaki's syndrome; headaches such as migraine, chronic tension headaches, cluster and vascular headaches, post-traumatic stress disorders; pain disorders such as neuropathic pain; myocardial and cerebral ischemia/reperfusion injury.

The compounds according to the invention can also be useful in the treatment of cancers that express nitric oxide synthase.

In the context of their properties, functions and usabilities mentioned herein, the compounds according to the invention are distinguished by valuable and desirable effects related therewith, such as, for example, high efficacy, low microsomal clearance, low serum protein binding, isoform selectivity, low toxicity, absent interaction with cytochrome P450 enzymes, superior therapeutic window, absence of significant side effects and further beneficial effects related with their therapeutic and pharmaceutical suitability.

The invention further relates to a method of treating or preventing one of the above mentioned diseases in a mammal, including a human, in need thereof comprising administering a therapeutically effective amount of at least one of the compounds according to the invention.

Especially, the invention relates to a method of treating or preventing a disease which is alleviated by inhibition of inducible nitric oxide synthase in a mammal, including a human, in need thereof comprising administering a therapeutically effective amount of at least one of the compounds according to the invention.

In particular, the invention relates to a method of treating or preventing an acute or chronic inflammatory disease, in particular sepsis, septic shock, systemic inflammatory response syndrome, hemorrhagic shock, shock states induced by cytokine therapy, asthma, chronic obstructive pulmonary disease, allergic rhinitis, cardiomyopathy or myocarditis, in a mammal, including a human, in need thereof comprising administering a therapeutically effective amount of at least one of the compounds according to the invention.

In the above methods, at least one of the compounds according to the invention can be used.

Preferably, one or two of the compounds according to the invention are used, more preferably, one of the compounds according to the invention is used.

In a particularly preferred embodiment of the invention, the above methods of treating or preventing one of the above mentioned diseases in a mammal, including a human, in need thereof comprise administering a therapeutically effective amount of one compound of the examples according to the invention. The invention further relates to the compounds according to the invention for the treatment or prophylaxis of diseases, especially diseases alleviated by inhibition of the inducible nitric oxide synthase, in particular the diseases exemplified above.

The invention also relates to the use of the compounds according to the invention in the manufacture of pharmaceutical compositions inhibiting the inducible nitric oxide synthase, in particular pharmaceutical compositions for the treatment or prophylaxis of diseases alleviated by inhibition of the inducible nitric oxide synthase.

The invention especially relates to the use of the compounds according to the invention in the manufacture of pharmaceutical compositions for the treatment or prophylaxis of the diseases exemplified above, preferably for the treatment or prophylaxis of acute or chronic inflammatory diseases, more preferably for the treatment or prophylaxis of sepsis, septic shock, systemic inflammatory response syndrome, hemorrhagic shock, shock states induced by cytokine therapy, asthma, chronic obstructive pulmonary disease, allergic rhinitis, cardiomyopathy or myocarditis.

The invention furthermore relates to pharmaceutical compositions which comprise at least one of the compounds according to the invention together with at least one pharmaceutically acceptable auxiliary.

Preferably, the pharmaceutical compositions comprise one or two of the compounds according to the invention. More preferably, the pharmaceutical compositions comprise one of the compounds according to the invention.

In a particularly preferred embodiment of the invention, the pharmaceutical compositions comprise a compound of the examples according to the invention together with at least one pharmaceutically acceptable auxiliary.

The invention furthermore relates to pharmaceutical compositions according to the invention inhibiting the inducible nitric oxide synthase, especially for the treatment or prophylaxis of diseases alleviated by inhibition of the inducible nitric oxide synthase, in particular for the treatment or prophylaxis of the diseases exemplified above.

The pharmaceutical compositions can contain at least one of the compounds according to the invention in a total amount of from 0.1 to 99.9 wt.%, preferably 5 to 95 wt.%, more preferably 20 to 80 wt.%.

As pharmaceutically acceptable auxiliaries, any auxiliaries known to be suitable for preparing pharmaceutical compositions can be used. Examples thereof include, but are not limited to, solvents, excipients, dispersants, emulsifiers, solubilizers, gel formers, ointment bases, antioxidants, preservatives, stabilizers, carriers, fillers, binders, thickeners, complexing agents, disintegrating agents, buffers, permeation promoters, polymers, lubricants, coating agents, propellants, tonicity adjusting agents, surfactants, colorants, flavorings, sweeteners and dyes. In particular, auxiliaries of a type appropriate to the desired formulation and the desired mode of administration are used.

The pharmaceutical compositions can be formulated, for example, into tablets, coated tablets (dragees), pills, cachets, capsules (caplets), granules, powders, suppositories, solutions (e.g. sterile solutions), emulsions, suspensions, ointments, creams, lotions, pastes, oils, gels, sprays and patches (e.g. transdermal therapeutic systems). Additionally, the pharmaceutical compositions can be prepared as e.g. liposome delivery systems, systems in which the compounds according to the invention are coupled to monoclonal antibodies and systems in which the compounds according to the invention are coupled to polymers (e.g. soluble or biodegradable polymers).

The pharmaceutical compositions comprising the compounds according to the invention and at least one pharmaceutical acceptable auxiliary can be manufactured in a manner known to a person skilled in the art, e.g. by dissolving, mixing, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping or lyophilizing processes.

The selected formulation depends inter alia on the route of administering the pharmaceutical composition. The pharmaceutical compositions of the invention can be administered by any suitable route, for example, by the oral, sublingual, buccal, intravenous, intraarterial, intramuscular, subcutaneous, intracutaneous, topical, transdermal, intranasal, intraocular, intraperitoneal, intrasternal, intracoronary, transurethral, rectal or vaginal route, by inhalation or by insufflation. Oral administration is preferred.

Tablets, coated tablets (dragees), pills, cachets, capsules (caplets), granules, solutions, emulsions and suspensions are e.g. suitable for oral administration. In particular, said formulations can be adapted so as to represent, for example, an enteric form, an immediate release form, a delayed release form, a repeated dose release form, a prolonged release form or a sustained release form. Said forms can be obtained, for example, by coating tablets, by dividing tablets into several compartments separated by layers disintegrating under different conditions (e.g. pH conditions) or by coupling the compounds according to the invention to a biodegradable polymer.

Administration by inhalation is preferably made by using an aerosol. The aerosol is a liquid-gaseous dispersion, a solid-gaseous dispersion or a mixed liquid/solid-gaseous dispersion.

The aerosol may be generated by means of aerosol-producing devices such as dry powder inhalers (DPIs), pressurized metered dose inhalers (PMDIs) and nebulizers. Depending on the kind of the compounds according to the invention to be administered, the aerosol-producing device can contain the compounds according to the invention in form of a powder, a solution or a dispersion. The powder may contain, for example, one or more of the following auxiliaries: carriers, stabilizers and fillers. The solution may contain in addition to the solvent, for example, one or more of the following auxiliaries: propellants, solubilizers (co-solvents), surfactants, stabilizers, buffers, tonicity adjusting agents, preservatives and flavorings. The dispersion may contain in addition to the dispersant, for example, one or more of the following auxiliaries: propellants, surfactants, stabilizers, buffers, preservatives and flavorings. Examples of carriers include, but are not limited to, saccharides, e.g. lactose and glucose. Examples of propellants include, but are not limited to, fluorohydrocarbons, e.g. 1 ,1 ,1 ,2- tetrafluoroethane and 1 ,1 ,1 ,2,3,3,3-heptafluoropropane.

The particle size of the aerosol particles (solid, liquid or solid/liquid particles) is preferably less than 100 μm, more preferably it is in the range of from 0.5 to 10 μm, in particular in the range of from 2 to 6 μm (D50 value, measured by laser diffraction).

Specific aerosol-producing devices which may be used for inhaled administration include, but are not limited to, Cyclohaler®, Diskhaler®, Rotadisk®, Turbohaler®, Autohaler®, Turbohaler®, Novolizer®, Easyhaler®, Aerolizer®, Jethaler®, Diskus®, Ultrahaler® and Mystic® inhalers. The aerosol- producing devices may be combined with spacers or expanders, e.g. Aerochamber®, Nebulator®, Volumatic® and Rondo®, for improving inhalation efficiency.

In case of topical administration, suitable pharmaceutical formulations are, for example, ointments, creams, lotions, pastes, gels, powders, solutions, emulsions, suspensions, oils, sprays and patches (e.g. transdermal therapeutic systems).

For parenteral modes of administration such as, for example, intravenous, intraarterial, intramuscular, subcutaneous, intracutaneous, intraperitoneal and intrasternal administration, preferably solutions (e.g. sterile solutions, isotonic solutions) are used. They are preferably administered by injection or infusion techniques.

In case of intranasal administration, for example, sprays and solutions to be applied in drop form are preferred formulations.

For intraocular administration, solutions to be applied in drop form, gels and ointments are exemplified formulations.

Generally, the pharmaceutical compositions according to the invention can be administered such that the dose of the compounds according to the invention is in the range customary for inducible nitric oxide synthase inhibitors. In particular, a dose in the range of from 0.01 to 4000 mg of the compounds according to the invention per day is preferred for an average adult patient having a body weight of 70 kg. In this respect, it is to be noted that the dose is dependent, for example, on the specific compound used, the species treated, age, body weight, general health, sex and diet of the subject treated, mode and time of administration, rate of excretion, severity of the disease to be treated and drug combination.

The pharmaceutical composition can be administered in a single dose per day or in multiple subdoses, for example, 2 to 4 doses per day. A single dose unit of the pharmaceutical composition can contain e.g. from 0.01 mg to 4000 mg, preferably 0.1 mg to 2000 mg, more preferably 0.5 to 1000 mg, most preferably 1 to 500 mg, of the compounds according to the invention. Furthermore, the pharmaceutical composition can be adapted to weekly, monthly or even more infrequent administration, for example by using an implant, e.g. a subcutaneous or intramuscular implant, by using the compounds according to the invention in form of a sparingly soluble salt or by using the compounds according to the invention coupled to a polymer.

Biological investigations

Measurement of inducible NO synthase activity:

The assay is performed in 96-well microtiter F-plates (Greiner, Frickenhausen, Germany) in a total volume of 100 μl in the presence of 100 nM calmodulin, 226 μM CaCI₂, 477 μM MgCI₂, 5 μM flavin- adenine-dinucleotide (FAD), 5 μM flavin mononucleotide (FMN), 0.1 mM nicotinamide adenine dinucleotide phosphate (NADPH), 7 mM glutathione, 10 μM tetrahydrobiopterine (BH4) and 100 mM 4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES) at pH 7.2. Arginine concentrations are 0.1 μM for enzyme inhibition experiments. 150000 dpm of [³H]arginine are added to the assay mixture. Enzyme reaction is started by the addition of 4 μg of a crude cytosolic fraction containing human inducible nitric oxide synthase and the reaction mixture is incubated for 45 to 60 minutes at 37⁰C. Enzyme reaction is stopped by adding 10 μl of 2M 2-morpholinoethane sulfonic acid (MES) buffer pH 5.0. 50 μl of the incubation mixture are transferred into a MADP N65 filtration microtiter plate (Millipore, Eschborn, Germany) containing already 50 μl of AG-50W-X8 cation exchange resin (Biorad, Munich, Germany). The resin in the Na loaded form is pre-equilibrated in water and 70 μl

(corresponding to 50 μl dry beads) are pipetted under heavy stirring with a 8 channel pipette into the filtration plate. After pipetting 50 μl of the enzyme reaction mixture onto the filtration plates, the plates are placed on a filtration manifold (Porvair, Shepperton, UK) and the flow through is collected in Pico scintillation plates (Packard, Meriden, USA). The resin in the filtration plates is washed with 75 μl of water (1x50 μl and 1x 25 μl) which is also collected in the same plate as the sample. The total flow through of 125 μl is mixed with 175 μl of Microscint-40 scintillation cocktail (Packard) and the scintillation plate is sealed with TopSeal P-foil (Packard). Scintillation plates are counted in a szintillation counter.

For the measurement of inducible nitric oxide synthase inhibiting potencies of the compounds according to the invention increasing concentrations of the compounds are included into the incubation mixture. IC₅₀ values are calculated from the percent inhibition at given concentrations by nonlinear least square fitting.

Inhibition of iNOS activity [measured as -loglC₅₀ (mol/l)]:

Claims

Claims

1. Compound of formula (I)

wherein X represents a halogen atom, a stereoisomer thereof or a salt of the compound or the stereoisomer thereof.

2. Compound according to claim 1 having formula (Ia)

wherein X represents a halogen atom, or a salt thereof.

3. Compound according to claim 1 having formula (Ib)

wherein X represents a halogen atom, or a salt thereof.

4. Compound according to any of claims 1 to 3, wherein X is selected from the group consisting of Br and I, or a salt thereof.

5. Compound according to claim 1 selected from the group consisting of 7-[2-(6-bromo-3H- imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine, (7S)-[2-(6-bromo-3H- imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,6,7-tetrahydro-3H-azepin-2-ylamine, (7R)-[2-(6-bromo-3H- imidazo[4,5-b]pyridin-2-yl)-ethyl]-4,5,

6,7-tetrahydro-3H-azepin-2-ylamine, and the salts thereof.

Process for producing a compound according to any of claims 1 to 5 comprising the step of reacting ammonia with a compound of formula (II)

wherein X represents a halogen atom.

7. Compound of formula (II)

wherein X represents a halogen atom.

8. Compound, stereoisomer thereof or pharmaceutically acceptable salt of the compound or the stereoisomer thereof according to any of claims 1 to 5 for the treatment of diseases.

9. Pharmaceutical composition comprising at least one of the compounds, stereoisomers thereof and pharmaceutically acceptable salts of the compounds and the stereoisomers thereof according to any of claims 1 to 5 together with at least one pharmaceutically acceptable auxiliary.

10. Use of a compound, stereoisomer thereof or pharmaceutically acceptable salt of the compound or the stereoisomer thereof according to any of claims 1 to 5 in the manufacture of a pharmaceutical composition inhibiting the inducible nitric oxide synthase.

11. Use of a compound, stereoisomer thereof or pharmaceutically acceptable salt of the compound or the stereoisomer thereof according to any of claims 1 to 5 in the manufacture of a pharmaceutical composition for the treatment or prophylaxis of an acute or chronic inflammatory disease.

12. Use according to claim 11 , wherein the acute inflammatory disease is selected from the group consisting of sepsis, septic shock, systemic inflammatory response syndrome, hemorrhagic shock and shock states induced by cytokine therapy.

13. Use according to claim 11 , wherein the chronic inflammatory disease is selected from the group consisting of asthma, chronic bronchitis, emphysema, chronic obstructive pulmonary disease, allergic rhinitis, cardiomyopathy and myocarditis.

14. Method of treating or preventing a disease in a mammal in need thereof comprising administering a therapeutically effective amount of at least one of the compounds, stereoisomers thereof and pharmaceutically acceptable salts of the compounds and the stereoisomers thereof according to any of claims 1 to 5.

15. Method of treating or preventing an acute or chronic inflammatory disease in a mammal in need thereof comprising administering a therapeutically effective amount of at least one of the compounds, stereoisomers thereof and pharmaceutically acceptable salts of the compounds and the stereoisomers thereof according to any of claims 1 to 5.

16. Method of treating or preventing sepsis, septic shock, systemic inflammatory response syndrome, hemorrhagic shock, shock states induced by cytokine therapy, asthma, chronic bronchitis, emphysema, chronic obstructive pulmonary disease, allergic rhinitis, cardiomyopathy or myocarditis in a mammal in need thereof comprising administering a therapeutically effective amount of at least one of the compounds, stereoisomers thereof and pharmaceutically acceptable salts of the compounds and the stereoisomers thereof according to any of claims 1 to 5.