2-hetarylthiazole-4-carboxamide derivatives, their preparation and use as pharmaceuticals

The present invention relates to 2-hetarylthiazole-4-carboxamide derivatives of the formula (I), the use thereof as medicament for the treatment of various disorders, and processes for the preparation thereof

The present invention relates to 2-hetarylthiazole-4-carboxamide derivatives of the formula (I), their use as medicaments for the treatment of various disorders, and processes for their preparation.

BIOLOGICAL BACKGROUND

An overreacting immune system is partly responsible for numerous chronic inflammatory disorders such as, for example, rheumatoid arthritis, Crohn's disease, asthma and multiple sclerosis. An increased release of proinflammatory cytokines leads to damage to endogenous tissue structures. The interplay of the innate and adaptive immune system is of central importance in this connection (Akira et al., 2001). Modulation of the immune system with substances which interfere with the activation of cells of the innate and/or of the adaptive immune system has antiinflammatory effects and can thus alleviate the pathological phenotype in the above disorders mentioned by way of example.

Innate immunity is based on the fact that microorganisms such as bacteria and viruses have certain inherent features via which they are recognized by the immune system and subsequently activate the latter. Certain pathogen-associated patterns (“pathogen associated molecular pattern, PAMPS”) are recognized. PAMPs are recognized by the pattern recognition receptors (PRR), which include Toll-like receptors (TLR) (Janeway and Medzhitov, 2002). TLRs are homologues of the drosophila receptor protein “toll”. There are ten different human TLRs. TLR one and six are coreceptors for TLR2. TLR2 recognizes inter alia lipoproteins and lipopeptides. TLR3 recognizes double-stranded RNA. TLR4 recognizes inter alia LPS of gram-negative and lipoteichoic acid of gram-positive bacteria. TLR5 recognizes flagellin, TLR9 recognizes CpG motifs in bacterial DNA (O'Neill, 2006). Coreceptors may further alter the recognition abilities of TLRs (Jiang et al., 2005).

TLRs are used in signal transduction with IL-1/IL-18 cytokine receptors. IL-1 (endogenous pyrogen) greatly stimulates inflammation and induces fever. Members of the IL-1R/TLR superfamily have a TIR domain (Toll/IL1 receptor). The TIR domain is about 200 amino acids long and comprises three conserved sequence motifs. Proteins having TIR domains bind via a protein-protein interaction (O'Neill et al., 2005). Subclass one (IL-1R family) comprises three Ig-like domains, and the receptor is a heterodimer. Included therein are IL-1 receptors one and two, the coreceptor IL-1 RAcP and the corresponding proteins of the IL-18 system. Subclass two (TLR family) comprises leucine-rich motifs. Toll-like receptors form homo- or heterodimers.

Activation of the TLR or IL-1, -18 receptors by the appropriate ligands initiates a multistage signal cascade. The TLR or IL-1/-18 receptor complex interacts via TIR/TIR contacts with the adaptor protein MyD88. The IL-1 associated receptor kinase (IRAK-1) normally has Tollip (Toll interacting protein) bound, which probably acts as an attenuating molecule (“silencer”). IRAK/Tollip binds to the active TLR/IL-1R complex. MyD88 displaces Tollip, thus activating IRAK1 and IRAK-4, most probably as dimer by transphosphorylation. Active IRAK leaves the receptor and binds in the cytoplasm to the adaptor molecule TRAF (Barton and Medzhitov, 2003). Further proteins are ubiquitinilated via TRAF. Ub-TRAF leads, by an unknown mechanism, to autophosphorylation of the S/T kinase TAK1 (an MAP kinase kinasekinase). TAK1 phosphorylates IκB (NF-κB activation) and MKK6. The latter is responsible for activating the MAP kinases p38 and JNK. NF-κB has been identified as nuclear factor for expression of the light antibody chain kappa in B cells, but is likewise involved in regulating many other genes. NF-κB is retained in the inactive state in the cytoplasm, where it is bound to the inhibitor IκB (Deng et al., 2000). Phosphorylation of IκB leads to proteolytic degradation of the inhibitor IκB, and the transcription factor is able to migrate into the nucleus. NF-κB is a heterodimer composed of the subunits p65 (Rel) and p50 (Bäuerle and Henkel, 1994). There are several members of this family which are able to interact in various ways. NF-κB alone cannot induce transcription. Transcriptional coactivators are necessary for gene activation, such as, for instance, p300 or CBT (Akira and Takeda, 2004).

Activation of receptors containing TIR domains is followed inter alia by release of inflammatory cytokines such as, for example, IL-1, IL-6, IL-23 and TNF-alpha (Adachi et al., 1998).

The structures of the following patent applications form the structurally close prior art:

WO2007/016292 describes N-aryl-2-arylthiazole-4-carboxamide derivatives as biofilm modulators (modulators of bacterial films) which differ because of the bicyclic C-D ring system from the compounds claimed herein.

WO2007/035478 discloses compounds which have a carboxyl group in the ortho position instead of a carboxamide group.

U.S. Pat. No. 6,274,738 describes N-aryl-2-pyridylthiazole-4-carboxamide derivatives as compounds which modulate DNA primase. However, these compounds cannot have an aminocarbonyl group on the N-aryl group in the ortho position relative to the pyridylthiazole-4-carboxamide unit. In addition, U.S. Pat. No. 4,879,295 discloses N-tetrazolylthiazolecarboxamides. Thiazolamide derivatives are mentioned in WO2006/122011 as inhibitors of viral replication. WO2005/048953 describes thiazolamide derivatives linked to an isoxazole unit as kinase inhibitors. The structures differ from the structures of the present invention, however.

The compounds disclosed in WO2007/052882 also do not have an aminocarbonyl group in the ortho position relative to the aminocarbonyl-thiazole group. A particular feature of the compounds described in WO2004072025 is, in contrast to the structures disclosed herein, a pyrrolidine ring which is additionally linked to a further substituent (such as, for example, a dimethylamino group) via a nitrogen atom.

WO200512256, WO200677424, WO2006077425 and WO200677428 disclose pyrazole derivatives as kinase inhibitors. Among the structures described are some in which a thiazolamide is linked to the pyrazole unit, although none of the pyrazole nitrogen atoms is in methylated form, and the pyrazole unit is not substituted by an aminocarbonyl group (C(O)NH2) either.

Pyrazolamides which are, however, simultaneously linked to a urea unit are described in WO2005/37797.

WO2005/115986 claims pyridinamides, but in this case no linkages to sulphur-containing heterocycles such as thiazole are envisaged.

Structurally different from the compounds described herein are also the pyridinamides described in WO2005/049604 because of the linkage to an oxygen-substituted phenyl ring.

EP1666455 describes amides with an additional carboxamide structure, it not being possible for the substituent R1 to be an aminocarbonyl group.

Starting from this prior art, the object of the present invention is to provide further structures for therapy, in particular for immunomodulation.

The object is achieved by compounds of the general formula (I) with building blocks A, B, C and D,

in whichthe building blocks B and D are in ortho position relative to one another, andQ1is a heteroaryl ring having 6 ring atoms, andR1and R2are independently of one another(i) hydrogen, hydroxyl, nitro, halogen, cyano, —CF3, —NR5R6or(ii) —C(O)—R10, —C(O)—R7, —C(O)—C1-C3-fluoroalkyl, —C(O)—NR5R6, —NH—C(O)—R7or(iii) a C1-C6-alkyl, C2-C6-alkenyl, C2-C6-alkynyl, C1-C6-alkoxy, C1-C6-fluoroalkyl or a C1-C6-fluoroalkoxy radical,in each case optionally substituted one or more times, identically or differently, by C1-C3-alkoxy, hydroxyl, —C(O)—R10or —NR8R9, or(iv) —O—SO2—NR5R6, —SO2—R7, —SO2—NR5R6, andQ2is an aryl, heteroaryl or a hydrogenated bicyclic heteroaryl ring; andR3and R4are independently of one another(i) hydrogen, halogen or —NR11R12or(ii) a C1-C6-alkyl or C1-C6-alkoxy radical which are in each case optionally substituted one or more times, identically or differently, by hydroxyl, C1-C3-alkoxy, —NR8R9or heterocyclyl, where the heterocyclyl ring may be substituted one or more times, identically or differently, by C1-C3-alkyl or —C(O)—R7, whereR5and R6are independently of one another hydrogen or a C1-C6-alkyl radical which is optionally substituted one or more times, identically or differently, by hydroxy, —C1-C3-alkoxy, —NR8R9or heterocyclyl, where the heterocyclyl ring may be substituted one or more times, identically or differently, by C1-C3-alkyl or —C(O)—R7, orR5and R6form alternatively together with the nitrogen atom a 5- to 7-membered ring which optionally comprises a further heteroatom in addition to the nitrogen atom, and which is optionally substituted one or more times, identically or differently, by C1-C6-alkyl and/or by —C(O)—R7, andR7is a C1-C6-alkyl radical, andR8, R9, R10are independently of one another hydrogen or a C1-C6-alkyl radical, andR11and R12are independently of one another hydrogen or a C1-C6-alkyl radical which is optionally substituted one or more times, identically or differently, by hydroxyl, —C1-C3-alkoxy, —NR8R9or heterocyclyl, where the heterocyclyl ring may be substituted one or more times, identically or differently, by C1-C3-alkyl or —C(O)—R7,
and the salts, enantiomers and diastereomers thereof.

The invention is based on the following definitions:

Monovalent, straight-chain or branched, saturated hydrocarbon radical having n carbon atoms.

A methyl, ethyl, propyl or isopropyl radical is preferred.

Monovalent, straight-chain or branched, saturated, completely or partly fluorinated, hydrocarbon radical having n carbon atoms.

A trifluoromethyl, 2,2,2-trifluoroethyl and pentafluoroethyl radical is preferred.

monovalent, straight-chain or branched hydrocarbon radical having n carbon atoms and at least one double bond.

A vinyl or allyl radical is preferred.

Monovalent, straight-chain or branched hydrocarbon radical having n carbon atoms and at least one triple bond.

An ethynyl, prop-1-ynyl or prop-2-ynyl radical is preferred.

Monovalent, cyclic hydrocarbon ring having n carbon atoms.

A cyclopropyl, cyclobutyl, cyclopentyl or a cyclohexyl ring is preferred.

Straight-chain or branched Cn-alkyl ether residue of the formula —OR with R=alkyl.

Straight-chain or branched Cn-fluoroalkyl ether residue of the formula —OR with R═Cn-fluoroalkyl.

Cn-Aryl is a monovalent, aromatic ring system without heteroatom having n hydrocarbon atoms.

Phenyl is preferred.

Heteroaryl is a monovalent, aromatic ring system having at least one heteroatom different from a carbon. Heteroatoms which may be present are nitrogen atoms, oxygen atoms and/or sulphur atoms. The valence bonds may be on any aromatic carbon atom or on a nitrogen atom.

A monocyclic heteroaryl ring according to the present invention has 5 or 6 ring atoms.

Heteroaryl rings having 6 ring atoms include for example the rings:pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl and triazinyl.

A bicyclic heteroaryl ring according to the present invention has 9 to 10 ring atoms.

Monocyclic heteroaryl rings having 5 or 6 ring atoms are preferred.

Hydrogenated bicyclic aryl or heteroaryl rings are bicyclic compounds in which one ring is in partly or completely hydrogenated form. The valence bond may be on any atom of the aromatic part of the hydrogenated bicyclic aryl or heteroaryl ring.

Hydrogenated bicyclic aryl or heteroaryl rings in which one ring is in partly or completely hydrogenated form may optionally comprise one or two carbonyl groups in the ring system.

Heterocyclyl in the context of the invention is a completely hydrogenated heteroaryl (completed hydrogenated heteroaryl=saturated heterocyclyl), i.e. a nonaromatic ring system having at least one heteroatom different from a carbon. Heteroatoms which may occur are nitrogen atoms, oxygen atoms and/or sulphur atoms. The valence bond may be on any carbon atom or on a nitrogen atom.

Heterocyclyl ring having 3 ring atoms includes for example:aziridinyl.

Heterocyclyl ring having 4 ring atoms includes for example:azetidinyl, oxetanyl.

Heterocyclyl rings having 5 ring atoms include for example the rings:pyrrolidinyl, imidazolidinyl, pyrazolidinyl and tetrahydrofuranyl.

Heterocyclyl rings having 6 ring atoms include for example the rings:piperidinyl, piperazinyl, morpholinyl, tetrahydropyranyl and thiomorpholinyl

Heterocyclyl rings having 7 ring atoms include for example the rings:azepanyl, oxepanyl, [1,3]-diazepanyl, [1,4]-diazepanyl.

Heterocyclyl rings having 8 ring atoms include for example:oxocanyl, azocanyl.

Heterocyclyl rings may optionally be partly unsaturated and/or also comprise a carbonyl group in the ring.

Halogen

The term halogen includes fluorine, chlorine, bromine and iodine.

Likewise to be regarded as encompassed by the present invention are all compounds which result from every possible combination of the abovementioned possible, preferred and particularly preferred meanings of the substituents.

Special embodiments of the invention moreover consist of compounds which result from combination of the meanings disclosed for the substituents directly in the examples.

Likewise to be regarded as encompassed by the present invention are the salts of the compounds.

Formulation of the compounds according to the invention to give pharmaceutical products takes place in a manner known per se by converting the active ingredient(s) with the excipients customary in pharmaceutical technology into the desired administration form.

Excipients which can be employed in this connection are, for example, carrier substances, fillers, disintegrants, binders, humectants, lubricants, absorbents and adsorbents, diluents, solvents, cosolvents, emulsifiers, solubilizers, masking flavours, colorants, preservatives, stabilizers, wetting agents, salts to alter the osmotic pressure or buffers. Reference should be made in this connection to Remington's Pharmaceutical Science, 15th ed. Mack Publishing Company, East Pennsylvania (1980).

The pharmaceutical formulations may bein solid form, for example as tablets, coated tablets, pills, suppositories, capsules, transdermal systems orin semisolid form, for example as ointments, creams, gels, suppositories, emulsions orin liquid form, for example as solutions, tinctures, suspensions or emulsions.

Excipients in the context of the invention may be, for example, salts, saccharides (mono-, di-, tri-, oligo-, and/or polysaccharides), proteins, amino acids, peptides, fats, waxes, oils, hydrocarbons and derivatives thereof, where the excipients may be of natural origin or may be obtained by synthesis or partial synthesis.

Suitable for oral or peroral administration are in particular tablets, coated tablets, capsules, pills, powders, granules, pastilles, suspensions, emulsions or solutions. Suitable for parenteral administration are in particular suspensions, emulsions and especially solutions.

One aspect of the invention is the use of the compounds according to the invention of the general formula (I) for manufacturing a pharmaceutical.

A further aspect of the invention is the use of the compounds according to the invention for the treatment of disorders associated with inflammatory, allergic and/or proliferative processes.

In the general formula (I), Q1may be a heteroaryl ring having 6 ring atoms.

Q1is particularly preferably a pyridyl or pyrazinyl ring.

In the general formula (I), Q2may be an aryl, heteroaryl or a hydrogenated bicyclic heteroaryl ring.

In the general formula (I), R3and R4may be independently of one another:(i) hydrogen, halogen or —NR11R12or(ii) a C1-C6-alkyl or C1-C6-alkoxy radical which are optionally substituted in each case one or more times, identically or differently, by hydroxy, C1-C3-alkoxy, —NR8R9or heterocyclyl, where the heterocyclyl ring may be substituted one or more times, identically or differently, by C1-C3-alkyl or —C(O)—R7.

R3and R4are preferably independently of one another:(i) hydrogen, halogen, —NR11R12or(ii) a C1-C6-alkyl or C1-C6-alkoxy radical, in each case optionally substituted by morpholine or —NR8R9.

R3and R4are particularly preferably independently of one another hydrogen, halogen or C1-C6-alkyl.

In the general formula (I), R5and R6can be independently of one another: hydrogen or a C1-C6-alkyl radical which is optionally substituted one or more times, identically or differently, by hydroxy, —C1-C3-alkoxy, —NR8R9or heterocyclyl, where the heterocyclyl ring may be substituted one or more times, identically or differently, by C1-C3-alkyl or —C(O)—R7,orR5and R6form alternatively together with the nitrogen atom a 5- to 7-membered ring which optionally comprises a further heteroatom in addition to the nitrogen atom and which is optionally substituted one or more times, identically or differently, by C1-C6-alkyl and/or by —C(O)—R7.

R5and R6are preferably independently of one another hydrogen or a C1-C6-alkyl radical which may optionally be substituted one or more times, identically or differently, by hydroxy, —NR8R9or C1-C3-alkoxy.

R5and R6are particularly preferably independently of one another hydrogen or a C1-C4-alkyl radical.

In the general formula (I), R7may be a C1-C6-alkyl radical.

In the general formula (I), R8, R9, R10may be independently of one another hydrogen or a C1-C6-alkyl radical.

It is preferred for R8and R9to be independently of one another hydrogen or a C1-C4-alkyl radical and for R10to be hydrogen.

It is particularly preferred for R8and R9to be independently of one another hydrogen or a C1-C3-alkyl radical and for R10 to be hydrogen.

In the general formula (I), R11and R12may be independently of one another:hydrogen or a C1-C6-alkyl radical which is optionally substituted one or more times, identically or differently, by hydroxy, —C1-C3-alkoxy, —NR8R9or heterocyclyl, where the heterocyclyl ring may be substituted one or more times, identically or differently, by C1-C3-alkyl or —C(O)—R7.

R11and R12are preferably independently of one another hydrogen or a C1-C6-alkyl radical which may optionally be substituted one or more times, identically or differently, by morpholine or by —N(CH3)2, —NH—CH3or —NH—C2H5.

A preferred subgroup is formed by compounds of the formula (I) with building blocks A, B, C and D, in which the building blocks B and D are in ortho position relative to one another andQ1is a pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl or triazinyl ring, andR1and R2are independently of one another(i) hydrogen, hydroxyl, halogen, cyano, —CF3, —NR5R6or(ii) a C1-C6-alkyl, C1-C6-alkoxy, C1-C6-fluoroalkyl or a C1-C6-fluoroalkoxy radical or(iii) —SO2R7, andQ2is a phenyl, thienyl, thiazolyl, furanyl, pyrrolyl, oxazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, 1,2,3-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,2,3,4-tetrahydroisoquinolinyl, 1,2,3,4-tetrahydroquinolinyl, 2,3-dihydro-1H-indolyl, 2,3-dihydro-1H-isoindolyl, 4,5,6,7-tetrahydrothieno[2,3-c]pyridinyl, 4,5,6,7-tetrahydrothieno[3,2-c]pyridinyl, 2,3-dihydrobenzofuranyl, benzo[1,3]dioxolyl, 2,3-dihydrobenzo[1,4]dioxinyl, 1,2,3,4-tetrahydroquinoxalinyl or a 3,4-dihydro-2H-benzo[1,4]oxazinyl ring, andR3and R4are independently of one another(i) hydrogen, halogen, —NR11R12or(ii) a C1-C6-alkyl or C1-C6-alkoxy radical,in each case optionally substituted by morpholine or —NR8R9,whereR5and R6are independently of one another hydrogen or a C1-C6alkyl radical which may optionally be substituted one or more times, identically or differently, by hydroxy, —NR8R9or C1-C3-alkoxy, andR7is a C1-C4alkyl radical, andR8and R9are independently of one another hydrogen or a C1-C4alkyl radical, andR11and R12are independently of one another hydrogen or a C1-C6alkyl radical which may optionally be substituted one or more times, identically or differently, by morpholine or by —N(CH3)2, —NH—CH3or —NH—C2H5,
and the salts, enantiomers and diastereomers thereof.

Particular preference is given to compounds of the general formula (I) with building blocks A, B, C and D in which the building blocks B and D are in ortho position relative to one another, andQ1is a pyridyl or pyrazinyl ring, andR1and R2are independently of one another(i) hydrogen, —NH2, hydroxy, halogen, —CF3, or(ii) a C1-C6-alkoxy, C1-C6-fluoroalkyl or a C1-C6-fluoroalkoxy radical, andQ2is a phenyl, pyrazolyl, thienyl, pyridinyl or 4,5,6,7-tetrahydrothieno[2,3-c]pyridinyl ring, andR3and R4are independently of one another hydrogen, halogen or C1-C6-alkyl,and the salts, enantiomers and diastereomers thereof.
Preparation of the Compounds According to the Invention
Process Variant 1:
a) Preparation of Intermediates of the Formula (III)

Intermediates of the formula (III) can be prepared in two synthetic stages. Firstly, intermediates of the formula (V) and ethyl bromopyruvate are converted by heating in organic solvents such as toluene into intermediates of the formula (IV).

The ethyl ester (IV) can then be hydrolysed, leading to the intermediates (III). In this case, Q1, R1and R2have the meanings indicated in general formula (I) above.

b) Preparation of the Final Product

The compounds according to the invention of the general formula (I) can be prepared by reacting the intermediates of formula (III) with compounds of the formula (II) through an amide coupling reagent (see Sigma-Aldrich publication Chemfiles, Peptide Synthesis, 2007, 7, No. 2). It is possible in this case to use for example carbodiimides (for example N-cyclohexyl-N′-(2-morpholinoethyl)carbodiimide metho-p-toluenesulphonate CAS2491-17-0) or uronium salts (for example O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU)) in combination with a base such as, for example, pyridine. In this case, Q1, Q2, R1, R2, R3and R4have the meanings indicated in general formula (I) above.

Process Variant 2:

a) Preparation of Intermediates of the Formula (VI)

2-Bromothiazole-4-carboxylic acid is reacted with intermediates of the formula (II) through an amide coupling reagent (see process variant 1) to give intermediates of the formula (VI).

b) Preparation of the Final Product

Intermediates of the formula (VI) are reacted with boronic acids or boronic acid pinacol esters in a Suzuki-Miyaura reaction to give the compounds according to the invention of the formula (I). Suitable catalysts or ligands in this case are for example the catalysts or catalyst systems described in N. Miyaura, A. Suzuki,Chem. Rev.;1995; 95(7); 2457-2483 or in C. J. O'Brien et al.Chem. Eur. J.2006, 12, 4743-4748 and in the Sigma-Aldrich publicationChemfiles, Catalysis2007, 7, No. 5.

Purification of the Compounds According to the Invention

In some cases, the compounds according to the invention can be purified by preparative HPLC, for example by an autopurifier apparatus from Waters (detection of the compounds by UV detection and electrospray ionization) in combination with commercially available, prepacked HPLC columns (for example XBridge column (from Waters), C18, 5 μm, 30×100 mm). Acetonitrile/water+0.1% trifluoroacetic acid can be used as solvent system (flow rate 50 ml/min). The HPLC solvent mixture can be removed by freeze-drying or centrifugation. The compounds obtained in this way may be in the form of trifluoroacetic acid (TFA) salts and can be converted into the respective free bases by standard laboratory procedures known to the skilled person. In some cases, the compounds according to the invention can be purified by chromatography on silica gel. In this case for example prepacked silica gel cartridges (for example Isolute® Flash silica gel from Separtis) in combination with a Flashmaster II chromatography apparatus (Argonaut/Biotage) and chromatography solvent or mixtures thereof such as, for example, hexane, ethyl acetate, and dichloromethane and methanol, can be considered.

Structural Analysis of the Compounds According to the Invention:

In some cases, the compounds according to the invention are analysed by LC-MS: retention times Rtfrom the LC-MS analysis: detection: UV=200-400 nm (Acquity HPLC system from Waters)/MS 100-800 daltons; 20 V (Micromass/Waters ZQ 4000) in ESI+mode (to generate positively charged molecular ions); HPLC column: XBridge (Waters), 2.1×50 mm, BEH 1.7 μm; eluents: A: H20/0.05% HC(O)OH, B: CH3CN/0.05% HC(O)OH. Gradient: 10-90% B in 1.7 min, 90% B for 0.2 min, 98-2% B in 0.6 min; flow rate: 1.3 ml/min. The statement LC-MS (ZQ) refers to the use of a Waters ZQ4000 apparatus and the statement LC-MS (SQD) refers to the use of a Single Quadrupole API (Atomic Pressure Ionization) mass detector (Waters) to record a mass spectrum.

Process Variant 1

2-(3-Pyridyl)thiazole-4-carboxylic acid (206 mg, 1 mmol) and 2-amino-benzamide (163 mg, 1.2 mmol) are mixed, and chloroform (10 ml) and pyridine (1.2 ml) are added. Then 1-hydroxybenzotriazole hydrate (230 mg) and 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide metho-P-toluene-sulphonate CAS[2491-17-0] (635 mg) are added, and the mixture is stirred at room temperature for 20 h. The solid is filtered off with suction and washed with ethyl acetate, water and again with ethyl acetate. Purification of the solid by preparative HPLC results in Example 1.1 as a white foam (58 mg).

Reaction of 2-(4-pyridyl)thiazole-4-carboxylic acid and 4-amino-2-methyl-2H-pyrazole-3-carboxamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[5-(aminocarbonyl)-1-methyl-1H-pyrazol-4-yl)-2-(4-pyridinyl)-4-thiazolecarboxamide as a white foam.

Reaction of 2-(4-pyridyl)thiazole-4-carboxylic acid and 2-aminobenzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)phenyl]-2-(4-pyridinyl)-4-thiazolecarboxamide as a white foam.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 2-amino-5-methyl-benzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)-4-methylphenyl]-2-(3-pyridinyl)-4-thiazolecarboxamide.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 2-amino-4-methyl-benzamide, subsequent filtration with suction and washing of the resulting solid with water and ethyl acetate, and drying in vacuo, in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)-5-methylphenyl]-2-(3-pyridinyl)-4-thiazolecarboxamide.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 2-amino-5-chloro-benzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)-4-chlorophenyl]-2-(3-pyridinyl)-4-thiazolecarboxamide as a solid.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid and 3-aminopyridine-2-carboxamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in 3-[(2-pyridin-3-ylthiazole-4-carbonyl)amino]pyridine-2-carboxamide as a solid.

Reaction of 2-(4-pyridyl)thiazole-4-carboxylic acid and 2-amino-4-methyl-benzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)-5-methylphenyl]-2-(4-pyridinyl)-4-thiazolecarboxamide as a solid.

Reaction of 2-(4-pyridyl)thiazole-4-carboxylic acid and 2-amino-6-methyl-4,5,6,7-tetrahydrothienyl[2,3-c]pyridine-3-carboxamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in 6-methyl-2-[(2-pyridin-4-ylthiazole-4-carbonyl)amino]-4,5,6,7-tetrahydro-thieno[2,3-c]pyridine-3-carboxamide as a solid.

Reaction of 2-(4-pyridiyl)thiazole-4-carboxylic acid and 4-amino-1-methyl-1H-pyrazole-3-carboxamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in 2-pyridin-4-ylthiazole-4-(3-carbamoyl-1-methyl-1H-pyrazol-4-yl)carboxamide as a solid.

a) Preparation of Intermediate III.1

4-(Trifluoromethyl)pyridine-3-thiocarboxamide (201 mg), ethyl bromo-pyruvate (122 microliters) and toluene (5 ml) are mixed and heated under reflux for 4 hours. The toluene is removed and the residue is taken up in dichloromethane. The organic phase is washed with water and saturated brine and dried over sodium sulphate. Removal of the solvent in a rotary evaporator results in a solid (266 mg) which is mixed with tetrahydrofuran (THF) (2 ml), ethanol (2 ml) and 1M sodium hydroxide solution (4 ml). The mixture is stirred at room temperature for 3.5 h and adjusted to pH 2 with 1M hydrochloric acid solution. The organic solvents are removed as far as possible, and the residue is mixed with ethyl acetate. The organic phase is washed with water and saturated brine, dried over sodium sulphate and concentrated. Intermediate III.1 is obtained as a brown solid (221 mg).

b) Preparation of the Final Product

Reaction of intermediate III.1 and 2-amino-4-methylbenzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)-5-methylphenyl]-2-[4-(trifluoromethyl)-3-pyridinyl]-4-thiazolecarboxamide as a solid.

a) Preparation of Intermediate III.2

2-(6-Trifluoroethoxypyridin-3-yl)thiazole-4-carboxylic acid is obtained as a solid starting from 6-(2,2,2-trifluoroethoxy)pyridine-3-thiocarboxamide CAS175277-59-5 and ethyl bromopyruvate in analogy to the synthesis of intermediate III.1.

b) Preparation of the Final Product

Reaction of intermediate III.2 and 2-amino-4-methylbenzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarbonyl)-5-methylphenyl]-2-[6-(2,2,2-trifluoro-ethoxy)-3-pyridinyl]-4-thiazolecarboxamide as a solid.

a) Preparation of Intermediate III.3

2-(6-Methoxypyridin-3-yl)thiazole-4-carboxylic acid is obtained as a crude product starting from 6-methoxypyridine-3-carbothiamide CAS175277-49-3 and ethyl bromopyruvate in analogy to the synthesis of intermediate III.1.

b) Preparation of the Final Product

Reaction of intermediate III.3 and 2-amino-4-methylbenzamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[2-(aminocarobnyl)-5-methylphenyl]-2-(6-methoxy-3-pyridinyl)-4-thiazolecarboxamide as a solid.

a) Preparation of Intermediate III.4

2-(Pyrazin-2-yl)thiazole-4-carboxylic acid (intermediate III.4) is obtained as crude product starting from pyrazine-2-carbothiamide and ethyl bromopyruvate in analogy to the synthesis of III.1.

b) Preparation of the Final Product

Reaction of intermediate III.4 and 4-amino-1-methyl-1H-pyrazole-3-carboxamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in N-[3-(aminocarbonyl)-1-methyl-1H-pyrazol-4-yl]-2-(pyrazin-2-yl)-4-thiazolecarboxamide as a solid.

Reaction of intermediate III.4 and 2-amino-6-methyl-4,5,6,7-tetrahydro-thieno[2,3-c]pyridine-3-carboxamide and subsequent purification by HPLC in analogy to the synthesis of Example 1.1 results in 6-methyl-2-[(2-pyrazin-2-ylthiazole-4-carbonyl)amino]-4,5,6,7-tetrahydrothieno[2,3-c]-pyridine-3-carboxamide as a solid.

Preparation of N-[5-(aminocarbonyl)-1-methyl-1H-pyrazol-4-yl]-2-(3-pyridinyl)-4-thiazolecarboxamide by amide coupling with HATU: 2-(3-Pyridyl)thiazole-4-carboxylic acid (82 mg, 0.4 mmol) and 4-amino-2-methyl-2H-pyrazole-3-carboxamide (56 mg, 0.4 mmol) are introduced into chloroform (3 ml) and pyridine (0.2 ml). Then HATU O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (228 mg) is added, and the mixture is stirred in a closed vessel at room temperature for 70 h. The precipitated solid is filtered off with suction, washed with ethyl acetate, water and again with ethyl acetate and dried in vacuo. Purification of the solid by HPLC results in Example 1.16 as a white foam.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 3-amino-5-(tert-butyl)thiophene-2-carboxamide and purification by HPLC in analogy to the synthesis of Example 1.16 results in N-[2-(aminocarbonyl)-5-(1,1-dimethyl-ethyl)-3-thienyl]-2-(3-pyridinyl)-4-thiazolecarboxamide as a solid.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 2-amino-5-fluorobenzamide and purification by HPLC in analogy to the synthesis of Example 1.16 results in N-[2-(aminocarbonyl)-4-fluorophenyl]-2-(3-pyridinyl)-4-thiazolecarboxamide as a solid.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 3-aminothiophene-2-carboxamide and purification by HPLC in analogy to the synthesis of Example 1.16 results in N-[2-(aminocarbonyl)-3-thienyl]-2-(3-pyridinyl)-4-thiazolecarboxamide as a solid.

Reaction of 2-(3-pyridyl)thiazole-4-carboxylic acid with 2-amino-4-methylthiophene-3-carboxamide and purification by HPLC in analogy to the synthesis of Example 1.16 results in N-[3-(aminocarbonyl)-4-methyl-2-thienyl]-2-(3-pyridinyl)-4-thiazolecarboxamide as a solid.

Reaction of 2-(4-pyridiyl)thiazole-4-carboxylic acid with 3-aminopyridine-2-carboxamide (Berrie et al.,J. Chem. Soc.1952, 2042) and purification by HPLC in analogy to the synthesis of Example 1.16 results in 3-[(2-pyridin-4-ylthiazole-4-carbonyl)amino]pyridine-2-carboxamide as a solid.

Reaction of 2-(4-pyridyl)thiazole-4-carboxylic acid with 3-aminoisonicotin-amide and purification by HPLC in analogy to the synthesis of Example 1.16 results in 3-[(2-pyridin-4-ylthiazole-4-carbonyl)amino]isonicotinamide as a solid.

Process Variant 2

a) Preparation of Intermediate VI.1

2-Bromo-4-thiazolecarboxylic acid (1 g), HATU (2.01 g) and 2-aminobenzamide (0.65 g) are introduced into N,N-dimethylformamide (DMF) (20 ml). The mixture is cooled with an ice bath, and N,N-diisopropylethylamine (0.90 ml) is added. The reaction mixture is stirred at room temperature for 6 days, poured into ice-water and allowed to thaw with stirring, and the precipitated solid is filtered off with suction, washed twice with water, twice with diethyl ether and dried in vacuo. Intermediate VI.1 is obtained as a solid (1.4 g).

b) Preparation of the Final Product

Intermediate VI.1 (65 mg, 0.2 mmol) and 2-methoxypyridine-5-boronic acid (43 mg, 0.28 mmol) are introduced into toluene (1.5 ml), ethanol (1.5 ml) and sodium carbonate solution (180 microliters, 2M) in a microwave vessel. Then Pd(PPh3)4(23 mg, 0.1 equivalent) is added, and the mixture is heated at 120° C. (300 watts) in the microwave (CEM Explorer apparatus from CEM) for 20 min. The mixture is diluted with water and extracted with ethyl acetate, and the organic phase is concentrated in a centrifuge and purified by HPLC.

N-[2-(aminocarbonyl)phenyl]-2-(2-methoxy-3-pyridinyl)-4-thiazolecarboxamide is obtained as a solid from intermediate VI.1 and 2-methoxypyridine-3-boronic acid in analogy to Example 2.1.

N-[2-(Aminocarbonyl)phenyl]-2-(5-chloro-3-pyridyl)-4-thiazolecarboxamide is obtained from intermediate VI.1 and 5-chloro-3-pyridylboronic acid in analogy to Example 2.5.

a) Preparation of Intermediate VI.2

2-Bromo-4-thiazolecarboxylic acid and 2-amino-4-methylbenzamide are reacted in analogy to the synthesis of intermediate VI.1 to give N-[2-(aminocarbonyl)-5-methylphenyl]-2-bromo-4-thiazolecarboxamide.

b) Preparation of the Final Product

Intermediate VI.2 (150 mg) and 2-amino-5-(4,4,5,5-tetramethyl-1,3,2-dioxa-borolan-2-yl)pyridine (CAS827614-64-2) (136 mg) are introduced into dimethylethylene glycol (3 ml) and aqueous sodium bicarbonate solution (2 ml, 1M) and then Pd(PPh3)4(102 mg, 0.2 equivalent) is added, and the mixture is heated in a microwave (CEM Explorer, 300 watt) at 110° C. for 45 min. It is diluted with water and extracted with ethyl acetate, the organic phase is concentrated, and the residue is purified by HPLC.

Intermediate VI.2 (150 mg) and 2-chloropyridine-4-boronic acid (84 mg) are introduced into dimethylglycol (3 ml) and aqueous sodium bicarbonate solution (2 ml, 1M). Pd(PPh3)4(51 mg) is added, and the mixture is heated in a microwave (300 W) (CEM Explorer apparatus) at 110° C. for 30 min. Then Pd(PPh3)4(52 mg) is again added, and the mixture is heated in the microwave at 110° C. for 30 min. Working up as in Example 2.1 and purification by HPLC result in N-[2-(aminocarbonyl)-5-methylphenyl]-2-(6-hydroxypyridin-3-yl)thiazole-4-carboxamide (9.8 mg) as a white solid.

Test Principle

PBMCs isolated from human whole blood are stimulated using a TLR ligand.

The cytokine determination is carried out by means of ELISA kits; a proliferation/cell metabolism determination is carried out using Alamar Blue.

For the cell preparation, about 200 ml of blood are treated with an anticoagulant (e.g. citrate Monovettes). Per Leucosep tube, 15 ml of Histopaque (room temperature, RT) are poured in and forced downwards through the inserted frit by brief initial centrifugation (one minute at 1000×g, RT). 20 ml of blood are added to the tubes prepared in this way and centrifuged at 800×g for 15 minutes (RT). After centrifugation, the following layering results from the top to the bottom:

plasma-PBMC-Histopaque-filter disc-Histopaque-erythrocytes and granulocytes. The supernatant plasma is aspirated. The PBMC are transferred together with the underlying Histopaque to a new 50 ml tube, the contents of two Leucosep tubes always being added to one 50 ml tube. The 50 ml tubes are then filled to 50 ml with PBS. This cell suspension is centrifuged at 300×g (RT) for 10 minutes.

The liquid supernatant is tipped off and the cell pellet is resuspended with a little PBS and subsequently filled to 50 ml with PBS. This washing step is repeated twice. The resulting pellet is taken up in a defined volume of medium (with additives). For the testing of the substances, PBMC are incubated for 18 hours with titrated concentrations of the test substances, e.g. in the presence or absence of TLR7 or TLR9 ligands. On the next day, the supernatants are investigated for the content of TNF-alpha or other cyto- or chemokines by means of specific ELISA. The metabolic activity of the treated cells is determined with the aid of Alamar Blue.

The entire disclosures of all applications, patents and publications, cited herein and of corresponding EP application No. 07076068.1, filed Dec. 10, 2007, and U.S. Provisional Application Ser. No. 61/022,649, filed Jan. 22, 2008, are incorporated by reference herein.