WO2018011265A1 - Hydroxyalkyl-piperazine derivatives as cxcr3 receptor modulators - Google Patents

Abstract

The invention relates to compounds of Formula (I), wherein X, R^1A, R^1B and R² are as described in the description; to pharmaceutically acceptable salts thereof, and to the use of such compounds as medicaments, especially as modulators of the CXCR3 receptor.

Description

Hydroxyalkyl-piperazine Derivatives as CXCR3 Receptor Modulators

The present invention relates to novel hydroxyalkyl-piperazine derivatives of Formula (I), and their use as pharmaceuticals. The invention also concerns related aspects including processes for the preparation of the compounds, pharmaceutical compositions containing one or more compounds of Formula (I), and especially their use as CXCR3 receptor modulators.

Chemokine receptors are a group of G-protein coupled receptors (GPCRs) that bind peptidic chemokine ligands with high affinity. The predominant function of chemokine receptors is to guide leukocyte trafficking to lymphoid organs and tissues under resting conditions as well as during inflammation, but a role for certain chemokine receptors on non-hematopoietic cells and their progenitors has also been recognized.

The chemokine receptor CXCR3 is a G-protein coupled receptor binding to the inflammatory chemokines CXCL9 (initially called MIG, monokine induced by interferon- γ [INF- γ]), CXCL10 (IP-10, INF-y-inducible protein 10), and CXCL1 1 (l-TAC, INF-y-inducible T cell a chemo-attractant). CXCR3 is mainly expressed on activated T helper type 1 (Th1 ) lymphocytes, but is also present on natural killer cells, macrophages, dendritic cells and a subset of B lymphocytes. The three CXCR3 ligands are expressed mainly under inflammatory conditions, expression in healthy tissue is very low. Cells that can express CXCR3 ligands, for instance after exposure to inflammatory cytokines such as interferon-γ or TNF- , include diverse stromal cells such as endothelial cells, fibroblasts, epithelial cells, keratinocytes but also includes hematopoietic cells such as macrophages and monocytes. The interaction of CXCR3 and its ligands (henceforth referred to as the CXCR3 axis) is involved in guiding receptor bearing cells to specific locations in the body, particularly to sites of inflammation, immune injury and immune dysfunction and is also associated with tissue damage, the induction of apoptosis, cell growth, and angiostasis. CXCR3 and its ligands are upregulated and highly expressed in diverse pathological situations including (auto-)immune/inflammatory mediated diseases, pulmonary diseases, cardiovascular diseases, infectious diseases, fibrotic disorders, neurodegenerative disorders, and tumor diseases.

A role of the CXCR3 axis in autoimmune disorders is corroborated by several preclinical and clinical observations. Autoimmune disorders in which histological analysis of inflammatory lesions or serum levels of patients revealed elevated levels of CXCR3 ligands or increased numbers of CXCR3 positive cells include rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), lupus nephritis, multiple sclerosis (MS), inflammatory bowel disease (IBD; comprising Crohn's disease and ulcerative colitis), and type I diabetes mellitus (Groom, J. R. & Luster, A. D. Immunol Cell Biol 201 1 , 89, 207; Groom, J. R. & Luster, A. D. Exp Cell Res 201 1 , 317, 620; Lacotte, S., Brun, S., Muller, S. & Dumortier, H. Ann N Y Acad Sci 2009, 1 173, 310). As expression of CXCR3 ligands is very low in healthy tissue, the above cited correlative evidence strongly suggest a role for CXCR3 in human autoimmune diseases.

Preclinical disease models performed with CXCR3 deficient mice, mice deficient for one of the CXCR3 ligands or the use of antibodies blocking the function of either CXCR3 or one of its ligands further corroborate a role for the CXCR3 axis in immune pathology. For instance, it has been shown that mice deficient for either CXCR3 or the CXCR3 ligand CXCL9 show reduced pathology in a model for lupus nephritis (Menke, J. et al. J Am Soc Nephrol 2008, 19, 1 177). In an animal model for another form of kidney inflammation, interstitial cystitis, administration of an antibody blocking CXCL10 function was shown to reduce pathology in cyclophosphamide-induced cystitis (Sakthivel, S. K. et al. J Immune Based Ther Vaccines 2008, 6, 6). Similarly, blocking CXCL10 with an antibody reduced pathology in a rat model of rheumatoid arthritis (Mohan, K. & Issekutz, T. B. J Immunol 2007, 179, 8463). Similarly, in a murine model of inflammatory bowel disease, a blocking antibody against CXCL10 could prevent pathology in a therapeutic setting (Singh, U. P. et al. J Interferon Cytokine Res 2008, 28, 31 ). Further, experiments performed with tissue from CXCR3 deficient mice suggests a role for CXCR3 in celiac disease, another autoimmune type disorder (Lammers, K. M. et al. Gastroenterology 2008, 135, 194).

Inflammatory diseases that are associated with an elevated expression of the CXCR3 axis include chronic obstructive pulmonary disorder (COPD), asthma, sarcoidosis, atherosclerosis and myocarditis (Groom, J. R. & Luster, A. D. Immunol Cell Biol 201 1 , 89, 207; Groom, J. R. & Luster, A. D. Exp Cell Res 2011 , 317, 620).

One study has shown that CXCR3 positive cells are increased in the lungs of smokers with COPD compared to healthy subjects and immunoreactivity for the CXCR3-ligand CXCL10 was present in the bronchiolar epithelium of smokers with COPD but not in the bronchiolar epithelium of smoking and nonsmoking control subjects (Saetta, M. et al. Am J Respir Crit Care Med 2002, 165, 1404). These findings suggest that the CXCR3 axis may be involved in the immune cell recruitment that occurs in peripheral airways of smokers with COPD. In agreement with these observations, a preclinical study of COPD revealed an attenuation of acute lung inflammation induced by cigarette smoke in CXCR3 deficient mice (Nie, L. et al. Respir Res 2008, 9, 82).

In one investigation of atherosclerosis, CXCR3 expression was found on all T cells within human atherosclerotic lesions. CXCR3 ligands CXCL9, CXCL10 and CXCL1 1 were all found in endothelial and smooth muscle cells associated with those lesions, suggesting that they are involved in the recruitment and retention of CXCR3 positive cells, particularly activated T lymphocytes, observed within vascular wall lesions during atherogenesis (Mach, F. et al. J Clin Invest 1999, 104, 1041 ).

Preclinical studies further support a role of CXCR3 in the development of atherosclerosis. CXCR3 genetic deletion in mice lacking ApoE results in a significantly reduced atherosclerotic lesion development within abdominal aortas (Veillard, N. R. et al. Circulation 2005, 1 12, 870).

A pivotal role for the CXCR3 axis has also been suggested in rejection reactions after organ transplantation and bone marrow transplantation related toxicity (Groom, J. R. & Luster, A. D. Exp Cell Res 201 1 , 317, 620). Preclinically, CXCR3 deficient mice show a significant resistance to allograft rejection (Hancock, W. W. et al. J Exp Med 2000, 192, 1515).

CXCR3 ligand plasma concentrations also positively correlate with diverse liver pathologies, including liver cirrhosis and fibrosis in humans (Tacke, F., et al. Liver Int 201 1 , 31 , 840).

In the field of oncology, blocking the CXCR3 axis has been proposed to help limit the metastatic spread of cancer cells. For instance, administration of the small molecule CXCR3 receptor antagonist AMG487 could limit the metastasis of tumor cells to the lungs (Pradelli, E. et al. Int J Cancer 2009, 125, 2586). Functional evidence for a role of CXCR3 in regulating B-cell chronic lymphocytic leukemia (CLL) was reported by Trentin and coworkers (Trentin, L. et al. J Clin Invest 1999, 104, 1 15).

In the central nervous system, blocking the CXCR3 axis may have beneficial effects and prevent neurodegeneration. Increased expression of CXCL10 in the CNS has been demonstrated in ischemia, Alzheimer's disease, multiple sclerosis (MS), and human immunodeficiency virus (HlV)-encephalitis. For example, ex vivo experiments have shown that tissue derived from either CXCR3 or CXCL10 deficient mice, neuronal cell death was diminished after neurotoxic NMDA-treatment when compared to tissue derived from wild type mice (van Weering, H. R. et al. Hippocampus 201 1 , 21 , 220). In a study looking to indentify drug-like molecules that provide neuroprotection against HTT fragment-induced neurodegeneration in a model for Huntington's disease, two CXCR3 receptor antagonists were identified (Reinhart, P. H. et al. Neurobiol Dis 201 1 , 43, 248.)

4-Thiazolyl-piperidine derivatives as CXCR3 receptor modulators have been disclosed in WO 2007/064553 and WO 2007/070433.

Different 1-(Piperazin-1-yl)-2-heteroaryl-ethanone derivatives as CXCR3 receptor modulators have been disclosed in WO 2007/100610, WO 2010/12681 1 , WO 2013/1 14332, WO 2015/01 1099, WO 2015/145322 and on a poster presentation (A. Prokopowicz et al., Optimization of a biaryl series of CXCR3 antagonists, 244^th ACS National Meeting, Philadelphia, US, August 19-23, 2012). It has now been found that hydroxyalkyl-piperazine derivatives of Formula (I) are potent CXCR3 modulators which may be useful for the treatment of diseases that are mediated or sustained through the CXCR3 axis, including (auto-)immune/inflammatory mediated diseases (e.g. rheumatoid arthritis, multiple sclerosis, Crohn's disease, ulcerative colitis, systemic lupus erythematosus, lupus nephritis, Sjogren Syndrome, sarcoidosis, systemic sclerosis, psoriasis, psoriatic arthritis, interstitial cystitis, celiac disease, myasthenia gravis, type I diabetes, uveitis, inflammatory myopathies, dry eye disease, thyroiditis including Grave's disease, transplant rejection, acute and/or chronic graft versus host disease), pulmonary diseases (e.g. asthma, chronic obstructive pulmonary disorder, pulmonary arterial hypertension), cardiovascular diseases (e.g. atherosclerosis, myocarditis), infectious diseases (e.g. influenza, cerebral malaria), fibrotic disorders (e.g. liver cirrhosis), neurodegenerative disorders (e.g. Alzheimer's disease, Huntington's chorea, neuromyelitis optica, chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome), and tumor diseases (e.g. brain tumor, colon cancer, breast cancer, and metastatic spread of cancer).

1 ) In a first embodiment, the present invention relates to com ounds of Formula (I)

Formula (I)

wherein

X represents N or CH; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents methyl, ethyl, /^'so-propyl or cyclopropyl; or

R^1A represents hydrogen, R^1B represents hydroxymethyl and R² represents methyl;

and to the salts (in particular pharmaceutically acceptable salts) of such compounds;

provided that the compound is not 1 -{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrim piperazin-1 -yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof;

1 -{(R)-2-Hydroxymethyl-4-[2 rifluoromethy^

piperazin-1 -yl}-2-(3-methyl-[1 ,2,4]triazol-1 -yl)-ethanone or a salt thereof;

1 (R)-2-Hydroxymethyl-4-[2 rifluoromethyL

piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone or a salt thereof; or

1 -{(S)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5^

piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone or a salt thereof.

Definitions provided herein are intended to apply uniformly to the compounds of Formula (I) as defined in any one of embodiments 1 ) to 1 1 ), and, mutatis mutandis, throughout the description and the claims unless an otherwise expressly set out definition provides a broader or narrower definition. It is well understood that a definition or preferred definition of a term defines and may replace the respective term independently of (and in combination with) any definition or preferred definition of any or all other terms as defined herein.

The compounds of Formula (I) as defined in any one of embodiments 1 ) to 1 1 ), contain an asymmetric carbon atom at the piperazine ring and are present in stereoisomerically essentially pure form, preferably as pure enantiomers.

The term "stereoisomerically essentially pure", for example when used in the context of enantiomers, is understood in the context of the present invention to mean especially that the respective enantiomer is present in a ratio of at least 98:2, and notably of at least 99: 1 with respect to the respective other enantiomer.

2) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein

X represents N or CH; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents methyl, ethyl, /^'so-propyl or cyclopropyl;

and to the salts (in particular pharmaceutically acceptable salts) of such compounds;

provided that the compound is not

1 -{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1 -yl}-2-(3-isopropyl-[1 ,2,4]triazol-1 -yl)-ethanone or a salt thereof;

1 -{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1 -yl}-2-(3-methyl-[1 ,2,4]triazol-1 -yl)-ethanone or a salt thereof; or

1 -{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone or a salt thereof. 3) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein

X represents N; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents ethyl or /^'so-propyl; or

R^1A represents hydrogen, R^1B represents hydroxymethyl and R² represents methyl;

and to the salts (in particular pharmaceutically acceptable salts) of such compounds;

provided that the compound is not

1-{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof.

4) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein

X represents N; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents ethyl or /^'so-propyl;

and to the salts (in particular pharmaceutically acceptable salts) of such compounds;

provided that the compound is not

1-{(R)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5-y^^ piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof.

5) Examples of compounds of Formula (I) as defined in embodiment 1 ) are selected from the group consisting of:

1-{(S)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl^ piperazin-1-yl}-2-(3-methyl-[1 ,2,4]triazol-1-yl)-ethanone;

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol- yl]-piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone;

2- (3-Ethyl-[1 ,2,4]triazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol- yl]-piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone;

2-(3-Ethyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone; and

2- (3-Cyclopropyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or salts (in particular pharmaceutically acceptable salts) of such compounds. 6) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein the compound is:

1-{(S)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol- piperazin-1-yl}-2-(3-methyl-[1 ,2,4]triazol-1-yl)-ethanone;

or a salt (in particular pharmaceutically acceptable salt) of the compound.

7) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein the compound is:

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluorometo

yl]-piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone;

or a salt (in particular pharmaceutically acceptable salt) of the compound.

8) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein the compound is:

2- (3-Ethyl-[1 ,2,4]triazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt (in particular pharmaceutically acceptable salt) of the compound.

9) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein the compound is:

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazo^^ yl]-piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone;

or a salt (in particular pharmaceutically acceptable salt) of the compound.

10) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein the compound is:

2- (3-Ethyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt (in particular pharmaceutically acceptable salt) of the compound.

1 1 ) A further embodiment of the invention relates to compounds of Formula (I) according to embodiment 1 ), wherein the compound is:

2-(3-Cyclopropyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt (in particular pharmaceutically acceptable salt) of the compound.

The invention, thus, relates to compounds of the Formula (I) as defined in embodiment 1 ), and to such compounds further limited by the characteristics of any one of embodiments 2) to 1 1 ), all under consideration of their respective dependencies; to pharmaceutically acceptable salts thereof; and to the use of such compounds as medicaments especially in the treatment of disorders relating to a dysfunction of the CXCR3 receptor or dysfunction of ligands signalling through CXCR3, such as (auto-)immune/inflammatory mediated diseases, pulmonary diseases, cardiovascular diseases, infectious diseases, fibrotic disorders, neurodegenerative disorders, and tumor diseases.

Where the plural form is used for compounds, salts, pharmaceutical compositions, diseases or the like, this is intended to mean also a single compound, salt, pharmaceutical composition, disease or the like.

Any reference to a compound of Formula (I) as defined in any one of embodiments 1 ) to 1 1 ) is to be understood as referring also to the salts (and especially the pharmaceutically acceptable salts) of such compounds, as appropriate and expedient.

The term "pharmaceutically acceptable salts" refers to salts that retain the desired biological activity of the subject compound and exhibit minimal undesired toxicological effects. Such salts include inorganic or organic acid and/or base addition salts depending on the presence of basic and/or acidic groups in the subject compound. For reference see for example 'Handbook of Pharmaceutical Salts. Properties, Selection and Use.', P. Heinrich Stahl, Camille G. Wermuth (Eds.), Wiley-VCH, 2008 and 'Pharmaceutical Salts and Co- crystals', Johan Wouters and Luc Quere (Eds.), RSC Publishing, 2012.

The present invention also includes isotopically labelled, especially ²H (deuterium) labelled compounds of Formula (I), which compounds are identical to the compounds of Formula (I) except that one or more atoms have each been replaced by an atom having the same atomic number but an atomic mass different from the atomic mass usually found in nature. Isotopically labelled, especially ²H (deuterium) labelled compounds of Formula (I) and salts thereof are within the scope of the present invention. Substitution of hydrogen with the heavier isotope ²H (deuterium) may lead to greater metabolic stability, resulting e.g. in increased in-vivo half-life or reduced dosage requirements, or may lead to reduced inhibition of cytochrome P450 enzymes, resulting e.g. in an improved safety profile. In one embodiment of the invention, the compounds of Formula (I) are not isotopically labelled, or they are labelled only with one or more deuterium atoms. In a sub-embodiment, the compounds of Formula (I) are not isotopically labelled at all. Isotopically labelled compounds of Formula (I) may be prepared in analogy to the methods described hereinafter, but using the appropriate isotopic variation of suitable reagents or starting materials.

Whenever the word "between" is used to describe a numerical range, it is to be understood that the end points of the indicated range are explicitly included in the range. For example: if a temperature range is described to be between 40 °C and 80 °C, this means that the end points 40 °C and 80 °C are included in the range; or if a variable is defined as being an integer between 1 and 4, this means that the variable is the integer 1 , 2, 3, or 4. Unless used regarding temperatures, the term "about" (or alternatively "around") placed before a numerical value "X" refers in the current application to an interval extending from X minus 10% of X to X plus 10% of X, and preferably to an interval extending from X minus 5% of X to X plus 5% of X. In the particular case of temperatures, the term "about" (or alternatively "around") placed before a temperature "Y" refers in the current application to an interval extending from the temperature Y minus 10°C to Y plus 10°C, and preferably to an interval extending from Y minus 5°C to Y plus 5°C. Besides, the term "room temperature" as used herein refers to a temperature of about 25°C.

The compounds of formula (I) as defined in any one of embodiments 1 ) to 1 1 ) and their pharmaceutically acceptable salts can be used as medicaments, e.g. in the form of pharmaceutical compositions for enteral (such as especially oral) or parenteral (including topical application or inhalation) administration.

The production of the pharmaceutical compositions can be effected in a manner which will be familiar to any person skilled in the art (see for example Remington, The Science and Practice of Pharmacy, 21st Edition (2005), Part 5, "Pharmaceutical Manufacturing" [published by Lippincott Williams & Wilkins]) by bringing the described compounds of Formula (I) or their pharmaceutically acceptable salts, optionally in combination with other therapeutically valuable substances, into a galenical administration form together with suitable, non-toxic, inert, therapeutically compatible solid or liquid carrier materials and, if desired, usual pharmaceutical adjuvants.

The present invention also relates to a method for the prevention/prophylaxis or treatment of a disease or disorder mentioned herein comprising administering to a subject a pharmaceutically active amount of a compound of Formula (I) as defined in any one of embodiments 1 ) to 1 1 ).

In a preferred embodiment of the invention, the administered amount is comprised between 1 mg and 1000 mg per day, particularly between 5 mg and 500 mg per day, more particularly between 25 mg and 400 mg per day, especially between 50 mg and 200 mg per day.

For avoidance of any doubt, if compounds are described as useful for the prevention or treatment of certain diseases, such compounds are likewise suitable for use in the preparation of a medicament for the prevention or treatment of said diseases.

Another aspect of the invention concerns a method for the prevention/prophylaxis or the treatment of a disease or disorder as mentioned below in a patient comprising the administration to said patient of a pharmaceutically active amount of a compound of Formula (I) as defined in any one of embodiments 1 ) to 11 ) or a pharmaceutically acceptable salt thereof. The compounds according to Formula (I) as defined in any one of embodiments 1 ) to 1 1 ), or pharmaceutically acceptable salts thereof, are useful for the prevention or treatment of disorders relating to a dysfunction of the CXCR3 receptor or dysfunction of ligands signalling through CXCR3.

Such disorders relating to a dysfunction of the CXCR3 receptor or its ligands are diseases or disorders where a modulator of a human CXCR3 receptor is required. The above mentioned disorders may in particular be defined as comprising (auto-)immune/ inflammatory mediated disorders; pulmonary disorders; cardiovascular disorders; infectious diseases; fibrotic disorders; neurodegenerative disorders; and tumor diseases.

(Auto-)immune/inflammatory mediated disorders may be defined as comprising rheumatoid arthritis (RA); multiple sclerosis (MS); inflammatory bowel disease (IBD; comprising Crohn's disease and ulcerative colitis); primary biliary cirrhosis (PBC) and autoimmune hepatitis; systemic lupus erythematosus (SLE); lupus nephritis; antiphospholipid syndrome; Sjogren Syndrome; sarcoidosis; systemic sclerosis; spondylarthritis; psoriasis; psoriatic arthritis; interstitial cystitis; celiac disease; thyroiditis such as Hashimoto's thyroiditis, lymphocytic thyroiditis, Grave's disease; myasthenia gravis; type I diabetes; uveitis; episcleritis; scleritis; Kawasaki's disease; uveo-retinitis; posterior uveitis; uveitis associated with Behcet's disease; uveomeningitis syndrome; allergic encephalomyelitis; atopic diseases such as rhinitis, conjunctivitis, dermatitis; post-infectious autoimmune diseases including rheumatic fever and post-infectious glomerulonephritis; myopathies (comprising inflammatory myopathies); obesity and transplant related disorders. Transplant related disorders may be defined as comprising transplant rejection such as rejection of transplanted organs such as kidney, liver, heart, lung, pancreas, cornea, and skin; acute and/or chronic graft-versus-host diseases; and chronic allograft vasculopathy.

Pulmonary diseases may be defined as comprising asthma; chronic obstructive pulmonary disorder (COPD); and pulmonary arterial hypertension.

Cardiovascular disorders may be defined as comprising atherosclerosis; and myocarditis.

Infectious diseases may be defined as comprising diseases mediated by various infectious agents and complications resulting threrefrom; such as malaria, cerebral malaria, leprosy, tuberculosis, influenza, toxoplasma gondii, dengue, hepatitis B and C, herpes simplex, leishmania, chlamydia trachomatis, lyme disease, and west nile virus.

Fibrotic disorders may be defined as comprising liver cirrhosis, idiopathic pulmonary fibrosis, renal fibrosis, endomyocardial fibrosis, systemic sclerosis, and arthrofibrosis.

Neurodegenerative disorders may be defined as comprising neurodegeneration and conditions involving neuronal death such as multiple sclerosis (including relapsing remitting multiple sclerosis and progressive multiple sclerosis), Alzheimer's disease, Parkinson's disease, Huntington's chorea, HIV associated dementia, prion mediated neurodegeneration, epilepsy, stroke, cerebral ischemia, cerebral palsy, neuromyelitis optica, clinically isolated syndrome, Alpers' disease, amyotrophic lateral sclerosis (ALS), senile dementia, dementia with Lewy bodies, Rett syndrome, spinal cord trauma, traumatic brain injury, trigeminal neuralgia, chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, narcolepsy, glossopharyngeal neuralgia, mild cognitive decline, cognitive decline, spinal muscular atrophy, and cerebral malaria.

Tumor diseases may be defined as comprising all sorts of cancers such as large intestine cancer, rectal cancer, breast cancer, lung cancer, non-small cell lung cancer, prostate cancer, esophagal cancer, stomach cancer, liver cancer, bile duct cancer, spleen cancer, kidney cancer, urinary bladder cancer, uterine cancer, ovarian cancer, cervical cancer, testicular cancer, thyroid cancer, pancreas cancer, brain tumor, blood tumor, basophil adenoma, prolactinoma, hyperprolactinemia, adenomas, endometrial cancer, colon cancer; chronic lymphocytic leukemia (CLL); and especially the metastatic spread of cancer.

Especially, compounds of Formula (I) according to any one of embodiments 1 ) to 1 1 ), or pharmaceutically acceptable salts thereof, are suitable for the prevention or treatment of diseases selected from one, several or all of the following groups of diseases and disorders:

1 ) (Auto-)immune/inflammatory mediated diseases selected from rheumatoid arthritis, multiple sclerosis, Crohn's disease, ulcerative colitis, primary biliary cirrhosis, autoimmune hepatitis, systemic lupus erythematosus, lupus nephritis, Sjogren Syndrome, sarcoidosis, systemic sclerosis, spondylarthritis, psoriasis, psoriatic arthritis, interstitial cystitis, celiac disease, myasthenia gravis, type I diabetes, uveitis, inflammatory myopathies, dry eye disease, thyroiditis including Grave's disease, transplant rejection, acute and/or chronic graft versus host disease, and (skin) fibrosis;

2) Pulmonary diseases selected from asthma, chronic obstructive pulmonary disorder, and pulmonary arterial hypertension;

3) Cardiovascular diseases selected from atherosclerosis, and myocarditis;

4) Infectious diseases selected from influenza, and cerebral malaria;

5) Fibrotic disorders selected from liver cirrhosis;

6) Neurodegenerative disorders selected from Alzheimer's disease, neurodegeneration, Huntington's chorea, neuromyelitis optica, chronic inflammatory demyelinating polyneuropathy, and Guillain-Barre syndrome;

7) Tumor diseases selected from brain tumor, colon cancer, breast cancer, and metastatic spread of cancer. Most preferably, compounds of Formula (I) according to any one of embodiments 1 ) to 1 1 ), or pharmaceutically acceptable salts thereof, are suitable for the treatment of rheumatoid arthritis, multiple sclerosis, Crohn's disease, ulcerative colitis, systemic lupus erythematosus, lupus nephritis, sarcoidosis, systemic sclerosis, psoriasis, psoriatic arthritis, interstitial cystitis, celiac disease, myasthenia gravis, type I diabetes, uveitis, inflammatory myopathies, dry eye disease, thyroiditis including Grave's disease, transplant rejection, acute and/or chronic graft versus host disease, asthma, chronic obstructive pulmonary disorder, pulmonary arterial hypertension, atherosclerosis, myocarditis, influenza, cerebral malaria, liver cirrhosis, Alzheimer's disease, neurodegeneration, Huntington's chorea, neuromyelitis optica, chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, brain tumor, colon cancer, breast cancer, and metastatic spread of cancer.

Preparation of compounds of Formula (I)

A further aspect of the invention is a process for the preparation of compounds of Formula (I). Compounds according to Formula (I) of the present invention can be prepared from commercially available or well known starting materials according to the methods described in the experimental part; by analogous methods; or according to the general sequence of reactions outlined below, wherein X, R^1A , R^{1 B} and R² are as defined for Formula (I). Other abbreviations used herein are explicitly defined, or are as defined in the experimental section. In some instances the generic groups R^1A and R^{1 B} might be incompatible with the assembly illustrated in the schemes below and so will require the use of protecting groups (PG). The use of protecting groups is well known in the art (see for example "Protective Groups in Organic Synthesis", T.W. Greene, P.G.M. Wuts, Wiley-lnterscience, 1999). For the purposes of this discussion, it will be assumed that such protecting groups as necessary are in place. The compounds obtained may also be converted into salts, especially pharmaceutically acceptable salts thereof in a manner known per se.

General preparation routes:

Compounds of Formula (I) can be prepared following the route in Scheme 1 . Commercially available 2-(trifluoromethyl)thiazole-4-carboxylic acid is treated with n-butyl lithium and bromine in THF at a temperature around -78°C. The resulting brominated compound can be esterified using concentrated sulphuric acid in MeOH and heating at a temperature around 70°C. Nucleophilic aromatic substitution using commercially available piperazine derivatives (1 ), in presence of a suitable base such as DIPEA, in a suitable solvent such as MeCN, and at a temperature around 80°C provides compounds of structure (2). Saponification under standard conditions (e.g. aq. NaOH in MeOH) gives compounds of structure (3). The compound of structure (3) is then converted to the corresponding bromine (4) using (diacetoxyiodo)benzene and LiBr in THF at RT. Suzuki coupling can be performed using a coupling partner of structure (5), wherein R represents hydrogen or (Ci_4)alkyl, using standard conditions for a Suzuki reaction, like using a suitable base such as aq. Na₂C0₃, a suitable palladium catalyst such as Pd(PPh₃)₂CI₂, and a suitable solvent such as MeCN preferably at a temperature around 80°C. The Boc protecting group of the obtained intermediate (6) can be subsequently cleaved under acidic conditions, preferably using HCI in a suitable solvent such as dioxane and at a temperature about RT to give the compound of structure (7). Compounds of Formula (I) can be obtained in a final step by an amide coupling with a carboxylic acid derivative (8) using standard peptide coupling methods such as HATU, in presence of a suitable base such as NEt₃ and in a suitable solvent such as DCM or DMF, preferably at a temperature about RT.

Scheme 1

The compounds of formula (8) are either commercially available, or can be synthesized following the route shown in Scheme 2.

Scheme 2

A compound of structure (9) can be alkylated using an acetic acid derivative of formula X- CH₂-COO(PG), wherein X is a leaving group such as bromine and PG is a protecting group suitable for an acid function (e.g. benzyl), in presence of a base such as Cs₂C0₃, in a suitable solvent such as MeCN, and at a temperature around RT.

Deprotection of the intermediate (10), such as benzyl deprotection under H₂, using Pd/C as catalyst and EtOH as solvent at a temperature around RT, leads to the compound of structure (8). Other suitable acid function protecting groups and protection and deprotection methods are well known to one skilled in the art (see notably "Protective groups in organic synthesis", Greene T. W. and Wuts P. G. M., Wiley-lnterscience, 1999).

Whenever the compounds of Formula (I) are obtained in the form of mixtures of enantiomers, the enantiomers can be separated using methods known to one skilled in the art: e.g. by formation and separation of diastereomeric salts or by HPLC over a chiral stationary phase such as a Daicel ChiralPak IC (5 μιη) column. Typical conditions of chiral HPLC are an isocratic mixture of eluent A (EtOH or /^'PrOH, in presence or absence of an amine such as NEt₃ or DEA) and eluent B (hexane or MeCN), at a flow rate of 0.8 to 16 imL/min.

Experimental section:

Abbrevations (as used herein and in the description above):

aq. aqueous

Boc ferf.-butyloxycarbonyl

BSA Bovine serum albumine

Bu butyl

CC column chromatography on silica gel

CHO Chinese hamster ovary

CV column volume

DCM dichloromethane

DEA diethylamine

DIPEA N-ethyldiisopropylamine

DMF dimethylformamide DMSO dimethylsulfoxide

EA ethyl acetate

EDTA ethylenediaminetetraacetic acid

EGTA ethylene glycol tetraacetic acid

Et ethyl

FBS fetal bovine serum

FLIPR Fluorescent imaging plate reader

Fluo-4-AM 2-{[2-(2-{5-[bis(carboxymethyl)amino]-2-methylphenoxy}ethoxy)-4-(2,7- difluoro-6-hydroxy-3-oxo-3/-/-xanthen-9- yl)phenyl](carboxymethyl)amino}acetic acid

G418 (2R,3S,4R,5R,6S)-5-amino-6-[(1 R,2S,3S,4R,6S)-4,6-diamino-3-

[(2R,3R,4R,5R)-3,5-dihydroxy-5-methyl-4-methylaminooxan-2-yl]oxy-2- hydroxycyclohexyl]oxy-2-(1-hydroxyethyl)oxane-3,4-diol h hour(s)

HATU 2-(7-Aza-1 H-benzotriazole-1-yl)-1 ,1 ,3,3-tetramethyluronium

Hep heptanes

HEPES 4-(2-hydroxyethyl)-piperazine-1-ethanesulfonic acid

HV High vacuum

HPLC high performance liquid chromatography

/^'Pr /^'so-propyl

LC liquid chromatography

m multiplet

M molarity [mol L^"1]

Me methyl

MS mass spectrometry

min minute(s)

NMR nuclear magnetic resonance spectroscopy

org. organic

PBS Phosphate buffered saline

Pd/C palladium on carbon

PG protecting group

Ph phenyl

Prep preparative

RT room temperature

s singulet

sat. Saturated

sec second(s) TFA trifluoroacetic acid

THF tetrahydrofuran

t_R retention time

Characterization methods used:

The LC-MS retention times have been obtained using the following elution conditions:

I) LC-MS (A):

Zorbax SB-Aq, 3.5 μιη, 4.6x50mm column thermostated at 40°C. The two elution solvents were as follows: solvent A= water + 0.04%TFA; solvent B = MeCN. The eluent flow rate was 4.5 mL/min and the characteristics of the eluting mixture proportion in function of the time t from start of the elution are summarized in the table below (a linear gradient being used between two consecutive time points):

Preparative LC-MS methods used:

The purifications by preparative LC-MS have been performed using the conditions described hereafter.

I) Preparative LC-MS (I):

A Zorbax column (SB-AQ, 30 x 75 mm, 5 μιη) was used. The two elution solvents were as follows: solvent A = water + 0.5% formic acid; solvent B = MeCN. The eluent flow rate was 75 mL/min and the characteristics of the eluting mixture proportion in function of the time t from start of the elution are summarized in the tables below (a linear gradient being used between two consecutive time points):

II) Preparative LC-MS (II):

An Atlantis column (Waters T3, 10 μιη OBD, 30x75 mm) was used. The two elution solvents were as follows: solvent A = water + 0.5% formic acid; solvent B = MeCN. The eluent flow rate was 75 mL/min and the characteristics of the eluting mixture proportion in function of the time t from start of the elution are summarized in the tables below (a linear gradient being used between two consecutive time points): t (min) 0 0.01 3.5 6.0 6.2 6.6

Solvent A (%) 70 70 5 5 70 70

Solvent B (%) 30 30 95 95 30 30

Preparative chiral HPLC methods used:

The purifications by preparative chiral HPLC have been performed using the conditions described hereafter.

I) Preparative chiral HPLC (I):

A ChiralPak IB column (5μιη, 30x250mm) was used. The elution solvent was Hep/EtOH 70/30, run for 1 1.8min and at a flow rate of 34mL/min.

II) Preparative chiral HPLC (II):

A ChiralPak IB column (5μιη, 30x250mm) was used. The elution solvent was Hep/EtOH 60/40, run for 9min and at a flow rate of 40mL/min.

III) Preparative chiral HPLC (III):

A ChiralPak IC column (5μιη, 30x250mm) was used. The elution solvent was Hep/EtOH 70/30, 0.1 % diethylamine, run for 12.9min and at a flow rate of 34mL/min.

IV) Preparative chiral HPLC (IV):

A (R,R) Whelk-01 column (10μιη, 50x250mm) was used. The elution solvent was Hep/EtOH 70/30, run for 16.3min and at a flow rate of 100mL/min.

Example 1 : 1-{(S)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1 -yl}-2-(3-methyl-[1 ,2,4]triazol-1 -yl)-ethanone

11 5-Bromo-2-trifluoromethyl-thiazole-4-carboxylic acid

To a solution of 2-(trifluoromethyl)thiazole-4-carboxylic acid (3.2g) in anhydrous THF (60mL) under argon cooled down to -78°C was added n-BuLi (1.6M in hexane, 21.3mL) dropwise over 15min so that the internal temperature did not rise above -60°C. A solution of Br₂ (0.92mL) in cyclohexane (8mL) was then added dropwise to keep the internal temperature below -60°C. The resulting mixture was stirred at -78°C for 2h and carefully quenched by addition of water (50mL). Citric acid (10%) was added until pH=2 and the mixture was extracted with EA. The org. layers were washed with brine, dried (MgS0₄), filtered off and evaporated to dryness to afford 4.15g of brown solid, used without further purification. LC-MS (A): t_R = 0.67min. F-NMR (CD₃OD): -63.57ppm (s).

12. 5-Bromo-2-trifluoromethyl-thiazole-4-carboxylic acid methyl ester

To a solution of intermediate 1.1 (12g), MeOH (130mL) was added H₂S0₄ (96%, 6.5mL) and the mixture stirred at 70°C for 3h. After cooling down, the reaction mixture was quenched with sat. aq. Na₂C0₃ and the solvent partially evaporated off. The residue was diluted with DCM and washed with aq. sat. Na2CC>3 (1 x), water (1x) and brine (1x), and the aq. phases were extracted with DCM (2x). The combined org. layers were dried over MgS0₄, filtrated off, evaporated and dried under HV to afford 12g of brown resin. LC-MS (A): t_R = 0.83min. F-NMR (CD₃OD): -63.59ppm (s).

1.3. (S)-2-Hydroxymethyl-4-(4-methoxycarbonyl-2-trifluoromethyl-t

carboxylic acid tert-butyl ester

To a solution of intermediate 1.2 (4g) in MeCN (100ml_) were added (S)-1-Boc-2- hydroxymethylpiperazine (3.07g) and DIPEA (3.54ml_) at RT. The reaction mixture was stirred at 80°C for 28h. After cooling down, the reaction mixture was diluted with EA and washed with water (2x) and brine. The aq. layers were extracted with EA. The combined org. layers were dried over MgS0₄, filtrated off and evaporated to dryness. The crude was purified by CC (Biotage, SNAP 340g, solvent A: Hep; solvent B: EA; gradient in %B: 30 over 3CV, 30 to 50 over 5CV, 50 over 3CV) to afford 4g of yellow foam. LC-MS (A): t_R = 0.87min; [M+H]⁺: 426.0.

1.4. (S)-4-(4-Carboxy-2-trifluoromethyl-thiazol-5-yl)-2-hydroxymethyl-piperazin

carboxylic acid tert-butyl ester

To a solution of intermediate 1.3 (3.96g) in EtOH (20ml_) was added 1 M NaOH (20ml_) at RT and the reaction mixture was stirred for 1 h10. The solvent was evaporated off and the residue acidified to pH 2-3 by the addition of aq. citric acid (10%). The aq. layer was extracted with DCM (3x) and the combined org. layers were dried over MgS0₄ and concentrated to dryness to afford 2.89g as beige solid. LC-MS (A): t_R = 0.79min; [M+H]⁺: 412.1.

1.5. (S)-4-(4-Bromo-2-trifluoromethyl-thiazol-5-yl)-2-hydroxymethyl-piperaz

acid tert-butyl ester

To a solution of intermediate 1.4 (2.88g) in THF (55mL) were added LiBr (614mg) and (diacetoxyiodo)benzene (2.3g) at RT. The resulting suspension was stirred at RT overnight. The reaction mixture was evaporated off and the residue taken up with H₂0/DCM and extracted with DCM (3x). The combined org. layers were dried over MgS0₄, filtrated off and evaporated to dryness. The crude was purified by CC (Biotage, SNAP 100g cartridge, solvent A: Hep; solvent B: EA; gradient in %B: 10 for 5CV, 10 to 30 over 5CV, 40 for 3CV) to afford 2.5g as white solid. LC-MS (A): t_R = 0.93min; [M+H]⁺: 445.9.

1.6. (S)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyri

yl]-piperazine-1 -carboxylic acid tert-butyl ester

A mixture of intermediate 1.5 (2.3g), 2-(trifluoromethyl)pyrimidine-5-boronic acid (1.65g), Pd(PPh₃)₂CI₂ (202mg), 1 M Na₂C0₃ (15mL) in MeCN (15mL) was vigorously stirred at 80°C under argon for 20h. The reaction mixture was allowed to cool down to RT, diluted with H₂0 and extracted with DCM (3x). The combined org. layers were dried over MgSCU, filtrated off and evaporated to dryness. The crude was purified by CC (Biotage, SNAP 340g cartridge, solvent A: Hep; solvent B: EA; gradient in %B: 10 for 5CV, 10 to 30 over 6CV, 30 for 3CV) to afford 2.22g (Cpd1 ) as yellow foam. LC-MS (A): t_R = 0.97min; [M+H]⁺: 514.0.

7. {(S)-4-[2-Trifluoromethyl-4-(2-trifluoromethyl^yrim^

methanol; as hydrochloride salt

A mixture of intermediate 1 .6 (2.25g) in HCI (22ml_, 4M in dioxane) was stirred at RT for 1 h. The reaction mixture was evaporated and dried under HV to give 2.18g (Cpd2) as brown foam. LC-MS (A): t_R = 0.67min; [M+H]⁺: 413.9 and [M+CH₃CN+H]⁺: 455.1 .

1.8. (3-Methyl-[1, 2,4]triazol-1-yl)-acetic acid benzyl ester

To a solution of 3-methyl-1 H-1 ,2,4-triazole (1 g) in MeCN (40mL) was added Cs₂C0₃ (3.72g) followed by benzyl bromoacetate (1 .89mL) and the mixture was stirred for 1 h at RT. The reaction mixture was diluted with EA and washed with water (2x) and brine. The aq. layers were extracted with EA (2x) and the combined org. layers were dried over MgS0₄, filtered off and evaporated to dryness. The residue was purified by CC (Biotage, SNAP 100g cartridge, solvent A: DCM; solvent B: DCM/MeOH 8:2; gradient in %B: 85/15 for 12CV, 85/15 to 75/25 for 2CV, 75/25 for 3CV) to afford 2.3g as yellowish oil (52:48 mixture of regioisomers). The mixture of regioisomers was purified by preparative chiral HPLC (I). Second eluting fraction: (3-methyl-[1 ,2,4]triazol-1-yl)-acetic acid benzyl ester. LC-MS (A): t_R = 0.67min; [M+H]⁺: 232.16. ¹ H-NMR (CDCI₃): 8.05 (s, 1 H); 7.40-7.30 (m, 5H); 5.23 (s, 0.95H, CH₂); 4.93-4.88 (3s, 2H); 2.42 (s, 3H). Roesy signal seen between CH (triazole) at 8.05ppm and CH₂ at 4.93-4.88ppm.

1.9. (3-Methyl-[1,2,4]triazol-1-yl)-acetic acid

A flask containing intermediate 1 .8 (820mg), Pd/C (189mg) in EtOH (35mL) was evacuated and backfilled with argon (3x), afterwards evacuated and backfilled with H₂ (3x) and the reaction mixture stirred at RT for 18h. The reaction mixture was filtered over a celite plug and the filtrate was evaporated to dryness to afford 491 mg as white solid. LC-MS (A): t_R = 0.18min; [M+H]⁺: 142.22.

1.10. 1-{(S)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl^yrim

5-yl]-piperazin- 1 -yl}-2-( 3-methyl-[ 1,2,4 Jtriazol- 1 -yl) -ethanone

To a solution of intermediate 1 .7 (50mg) in DCM (1 .5mL) were added intermediate 1 .9 (13.5mg), NEt₃ (60μί) and HATU (47mg) at RT and the mixture was stirred at RT for 2h. After removal of the solvent, the crude was purified by Prep LC-MS (I) to afford 1 1 mg as white solid. LC-MS (A): t_R = 0.79min; [M+H]⁺: 537.1 . The amine coupling partners and their Boc-protected precursors can be synthesized according to Example 1 , for example by exchanging in step 1.3 (S)-1-Boc-2- hydroxymethylpiperazine by (R)-1-Boc-2-hydroxymethylpiperazine to obtain Cpd 3/4 (Table 1 ).

Table 1. Amine coupling partners and their Boc-protected precursors (LC-MS(A))

Example 2: 2-(3-Ethyl-[1 ,2,4]triazol-1 -yl)-1 -{(R)-2-hydroxymethyl-4-[2-trifluoromethyl- 4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone

2.1 (3-Ethyl-[1,2,4]triazol-1-yl)-acetic acid benzyl ester

This compound was prepared using a method analogous to that of Example 1 , step 1.8, 3- ethyl-1 H-1 ,2,4-triazole replacing of 3-methyl-1 H-1 ,2,4-triazole. The mixture of regioisomers was purified by preparative chiral HPLC (II). Second eluting fraction: (3-ethyl-[1 ,2,4]triazol-1- yl)-acetic acid benzyl ester: LC-MS (A): t_R = 0.71 min; [M+H]⁺: 246.2. Roesy signal seen between CH at 8.08 ppm and CH₂C0₂ at 4.96ppm.

2.2. (3-Ethyl-[1,2,4]triazol-1-yl)-acetic acid

This compound was prepared using a method analogous to that of Example 1 , step 1.9, intermediate 2.1 replacing intermediate 1.8. LC-MS (A): t_R = 0.25min; [M+H]⁺: 156.2.

2.3. 2-(3-Ethyl-[1,2 ]triazol-1-yl)-1-{(R)-2-hydroxymethyl^

trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]^iperazin-1-yl}-ethanone

To a solution of Cpd4 (30mg) in DMF (1 mL) were added intermediate 2.2 (13.5mg), NEt₃ (24μί) and HATU (28mg) at RT and the mixture was stirred at RT overnight. The crude mixture was directly purified by Prep LC-MS (II) to afford 1 1 mg as white solid. LC-MS (A): t_R = 0.81 min; [M+H]⁺: 551.1.

Example 3: 2-(3-Ethyl-pyrazol-1 -yl)-1 -{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone

3.1. (3-Ethyl-pyrazol-1-yl)-acetic acid benzyl ester

This compound was prepared using a method analogous to that of Example 1 , step 1.8, 3- ethyl-1 H-pyrazole replacing of 3-methyl-1 H-1 ,2,4-triazole. The mixture of regioisomers was purified by preparative chiral HPLC (III). First eluting fraction: (3-ethyl-pyrazol-1-yl)-acetic acid benzyl ester: LC-MS (A): t_R = 0.82min; [M+H]⁺: 245.1. Roesy signal seen between CH at 7.39 ppm and CH₂C0₂ at 4.90ppm.

3.2. (3-Ethyl-pyrazol-1-yl)-acetic acid

This compound was prepared using a method analogous to that of Example 1 , step 1.9, intermediate 3.1 replacing intermediate 1.8. LC-MS (A): t_R = 0.25min; [M+H]⁺: 156.2.

3.3. 2-(3-Ethy^yrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluorom

pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone

This compound was prepared using a method analogous to that of Example 2, step 2.3, intermediate 3.2 replacing intermediate 2.2. LC-MS (A): t_R = 0.89min; [M+H]⁺: 550.1. Example 4: 2-(3-Cyclopropyl-pyrazol-1 -yl)-1 -{(R)-2-hydroxymethyl-4-[2- trifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}- ethanone

This compound was prepared using a method analogous to that of Example 2, step 2.3, (3- cyclopropyl-1 H-pyrazol-1-yl)acetic acid replacing intermediate 2.2. LC-MS (A): t_R = 0.9min; [M+H]⁺: 562.0.

Example 5: 1-{(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-2-(3-isopropyl-[1,2,4]triazol-1-yl)-ethanone

5.1. (3-lsopropyl-[1,2,4]triazol-1-yl)-acetic acid benzyl ester

This compound was prepared using a method analogous to that of Example 1 , step 1.8, 3- isopropyl-1 H-1 ,2,4-triazole replacing 3-methyl-1 H-1 ,2,4-triazole. The mixture of regioisomers was purified by preparative chiral HPLC (IV). First eluting fraction: (3- isopropyl-[1 ,2,4]triazol-1-yl)-acetic acid benzyl ester. LC-MS (A): t_R = 0.76min; [M+H]⁺: 260.2. Roesy signal seen between CH₂ at 4.96ppm and CH (triazole) at 8.08ppm.

5.2. (3-lsopropyl-[ 1, 2, 4]triazol- 1-yl)-acetic acid

This compound was prepared using a method analogous to that of Example 1 , step 1.9, intermediate 5.1 replacing intermediate 1.8. LC-MS (A): t_R = 0.30min; [M+H]⁺: 170.2.

5.3. 1-{(S)-2-(2^ydroxy-ethyl)-4-[2-trifluoromethyl-4-(2^

thiazol-5-yl]-piperazin-1-yl}-2-(3-isopropyl-[1,2,4]triazol-1-yl)-ethanon

This compound was prepared using a method analogous to that of Example 2, step 2.3, Cpd6 replacing Cpd4 and intermediate 5.2 replacing intermediate 2.2. LC-MS (A): t_R = 0.86min; [M+H]⁺: 579.1.

Example 6: 1-{(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-2-(3-methyl-pyrazol-1-yl)-ethanone

This compound was prepared using a method analogous to that of Example 2, step 2.3, Cpd6 replacing Cpd4 and (3-methyl-1 H-pyrazol-1-yl)acetic acid replacing intermediate 2.2. LC-MS (A): t_R = 0.87min; [M+H]⁺: 550.1.

II. BIOLOGICAL ASSAYS

A) FLIPR assay: The bioactivity of compounds is tested in a fluorometric imaging plate reader (FLIPR: Molecular Devices) using engineered CHO-K1 cells expressing the human CXCR3A (GenBank: AY242128) coupled to a G protein (Galpha(16)). Cells are plated the day prior to bioassay in F12 medium supplemented with 10% FBS and G418 and hygromycin antibiotics to maintain recombinant selection. At the day of bioassay, cells are washed and dye loaded for one hour with Fluo-4-AM (Invitrogen) in Hanks Balanced Salt Solution (Invitrogen), buffered with 20 mM Hepes at pH 7.4 and sodium bicarbonate (0.038%), containing 5 mM probenecid. This buffer, but lacking the dye and containing probenecid at a concentration of 2.5 mM, is also used for washing steps (wash buffer); or lacking both dye and probenecid but supplemented with 0.1 % BSA for compound dilution steps (dilution buffer). Cells are washed free of excess dye and 60 microliter of wash buffer is added. Stock solutions of test compounds are made up at a concentration of 10 mM in DMSO, and serially diluted in dilution buffer to concentrations required for inhibition dose response curves. After a 10 minute incubation period at 37°C, 10 microliters of each compound dilution are transferred from a compound plate to the plate containing the recombinant cells in the FLIPR instrument according to the manufacturer's instructions. Following basal readings, 10 microliter CXCL10 agonist at a concentration of 20 nM (from Peprotech) is added, again using the FLIPR instrument. Changes in fluorescence are monitored before and after addition of the test compounds. Emission peak values above base level after CXCL10 addition are exported after base line subtraction.

The calculated IC₅₀ values may fluctuate depending on the daily assay performance. Fluctuations of this kind are known to those skilled in the art. In the case where IC₅o values have been determined several times for the same compound, mean values are given. Data are shown in Table 1.

Table 1

B): Receptor internalization assay: Stock solutions of test compounds are made up at a concentration of 10 mM in DMSO, and serially diluted in PBS containing 0,5% BSA to concentrations required for inhibition dose response curves. Diluted compounds are then mixed with an equal volume of CXCL10 (Peprotech) diluted in PBS. Anticoagulated venous human whole blood is added to the mixture, which is then incubated in a C0₂ incubator at 37°C to allow for ligand mediated receptor internalization (final CXCL10 concentration is 9 nM). After 30min, the blood is mixed with fluorescently labeled CXCR3 and CD4 specific antibodies (Becton Dickinson) and incubated on ice for 10 minutes. Samples are then mixed with BD FACS Lysing Solution (Becton Dickinson) in order to eliminate red blood cells. After washing the cells with PBS containing 0,5% BSA, the samples are then analyzed in a flow cytometer (FACS Canto II, Becton Dickinson). For data analysis using FACSDiva software (Becton Dickinson), the mean fluorescence corresponding to CXCR3 cell surface expression was determined on CD4 positive cells. The program GraphPad Prism or similar software is used to fit the data to a single site dose response curve and to calculate IC₅o values.

The calculated IC₅₀ values may fluctuate depending on the daily assay performance. Fluctuations of this kind are known to those skilled in the art. In the case where IC₅o values have been determined several times for the same compound, mean values are given. Data are shown in Table 2.

Table 2

C) hERG Q-Patch assay: Compounds are evaluated for block of the hERG K channel using CHO cells stably expressing the hERG gene (accession number U04270, bSys, Witterswil, Switzerland) and the QPatch robotic platform (Sophion, Ballerup, Denmark) in single-cell mode at room temperature. Cells are grown in culture flasks at 37°C in 5% C0₂, in culture medium (Ham's F-12 Nutrient Mixture, Invitrogen 21765-029) supplemented with 9% (v/v) fetal calf serum, 0.9% Penicillin/Streptomycin (10.000 U/mL, Invitrogen 15140148), 100 pg/mL Hygromycin B (Invitrogen 10687010). When the cells are -80% confluent (every 2-3 days), they are either split for further culture or used for electrophysiology. For further culture, cells are detached with 0.25% Trypsin EDTA solution (Invitrogen 25200-056) and a fraction of the cells (10-30%) is reseeded in culture medium. For electrophysiology, on the experimental day, cells are detached with 0.25% Trypsin EDTA solution and all cells are suspended in suspension medium (293 SFM II, Invitrogen 1 1686-029) supplemented with 20 mM HEPES and 0.04 mg/mL Trypsin inhibitor. Cells are kept in suspension medium at 32-35°C in the QPatch robot until use, at which time aliquots are transferred to the extracellular solution (in mM: NaCI 150: KCI 4; CaCI₂ 1.2; MgCI₂ 1 ; HEPES 10; pH 7.4 with NaOH) containing 0.3 %v/v DMSO and applied to the test plates. K' currents are measured with the patch-voltage-clamp technique in the whole-cell configuration with the internal solution (in mM: KCI, 140; NaCI, 10; MgCI₂. 1 ; HEPES, 10; EGTA, 5; pH = 7.2 with KOH). Currents are low-pass filtered using the internal Bessel filter of the QPatch robot with a cutoff frequency of 2 kHz and are digitized at 10 kHz. K^* tail currents are produced from a holding voltage of -80 mV by a 500-ms depolarization to +20 mV followed by a 500-ms repolarization to -40 mV; tail current amplitudes are measured at the end of the repoiarization to -40 mV. The pulse pattern is repeated every 10 sec during the experiment, baseline K' current is measured after 3 min in extracellular solution, test-solution containing compound is then applied, and K' current in presence of compound is measured 3 minutes after application to the cells. The respective test-solution is prepared by (1 ) dissolving the test-compound in pure DMSO, (2) diluting this DMSO solution in extracellular solution, and (3) adding further DMSO, such that the final test-solution has a concentration of either 300 nM or 3000 nM of the test-compound and contains 0.3 %v/v DMSO. Compound effects are quantified as % block by dividing the current in presence of compound by the baseline current; two or three experiments are performed for each compound and the final value represents the mean of the results of each experiment. Data are shown in Table 3.

Table 3

concentration concentration

Example No % block % block

[nM] [nM]

1 300 4 3000 10

2 300 2 3000 1

3 300 4 3000 26

4 300 3 3000 25

5 300 7 3000 -4

6 300 8 3000 16

Claims

Claims

1. A compound of Formula (I)

Formula (I)

wherein

X represents N or CH; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents methyl, ethyl, /^'so-propyl or cyclopropyl; or

R^1A represents hydrogen, R^1B represents hydroxymethyl and R² represents methyl;

or a salt thereof;

provided that the compound is not

1-{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof;

1-{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-methyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof;

1-{(R)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-methyl-pyrazol-1-yl)-ethanone or a salt thereof; or

1-{(S)-2-Hydroxymethyl-4-[2 rifluoromethyl-4-(2 rifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-methyl-pyrazol-1-yl)-ethanone or a salt thereof.

2. A compound according to claim 1 , wherein

X represents N or CH; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents methyl, ethyl, /^'so-propyl or cyclopropyl;

or a salt thereof;

provided that the compound is not 1-{(R)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimid piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof;

1-{(R)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidi

piperazin-1-yl}-2-(3-methyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof; or

1-{(R)-2-Hydroxymethyl-4-[2-trifluorometh^^

piperazin-1-yl}-2-(3-methyl-pyrazol-1-yl)-ethanone or a salt thereof.

3. A compound according to claim 1 , wherein

X represents N; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents ethyl or /^'so-propyl; or

R^1A represents hydrogen, R^1B represents hydroxymethyl and R² represents methyl;

or a salt thereof;

provided that the compound is not

1-{(R)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof.

4. A compound according to claim 1 , wherein

X represents N; and

R^1A represents hydroxymethyl or 2-hydroxyethyl, R^1B represents hydrogen and R² represents ethyl or /^'so-propyl;

or a salt thereof;

provided that the compound is not

1-{(R)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone or a salt thereof.

5. A compound according to claim 1 selected from the group consisting of:

1-{(S)-2-Hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]- piperazin-1 -yl}-2-(3-methyl-[1 ,2,4]triazol-1 -yl)-ethanone;

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5- yl]-piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone;

2- (3-Ethyl-[1 ,2,4]triazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromethyl-4-(2-trifluoromethyl-pyrimidin-5-yl)-thiazol-5- yl]-piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone;

2- (3-Ethyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone; and 2-(3-Cyclopropyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt thereof.

6. A compound according to claim 1 wherein the compound is:

1-{(S)-2-Hydroxymethyl-4-[2-trifluoromethy

piperazin-1 -yl}-2-(3-methyl-[1 ,2,4]triazol-1 -yl)-ethanone;

or a salt thereof.

7. A compound according to claim 1 wherein the compound is:

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromet^

yl]-piperazin-1-yl}-2-(3-isopropyl-[1 ,2,4]triazol-1-yl)-ethanone;

or a salt thereof.

8. A compound according to claim 1 wherein the compound is:

2- (3-Ethyl-[1 ,2,4]triazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt thereof.

9. A compound according to claim 1 wherein the compound is:

1- {(S)-2-(2-Hydroxy-ethyl)-4-[2-trifluoromet^^^

yl]-piperazin-1 -yl}-2-(3-methyl-pyrazol-1 -yl)-ethanone;

or a salt thereof.

10. A compound according to claim 1 wherein the compound is:

2- (3-Ethyl-pyrazol-1-yl)-1-{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2-trifluoromethyl- pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt thereof.

1 1. A compound according to claim 1 wherein the compound is:

2-(3-Cyclopropyl-pyrazol-1 -yl)-1 -{(R)-2-hydroxymethyl-4-[2-trifluoromethyl-4-(2- trifluoromethyl-pyrimidin-5-yl)-thiazol-5-yl]-piperazin-1-yl}-ethanone;

or a salt thereof.

12. A pharmaceutical composition comprising, as active principle, a compound according to any one of claims 1 to 1 1 , or a pharmaceutically acceptable salt thereof, and at least one therapeutically inert excipient.

13. A compound according to any one of claims 1 to 1 1 , or a pharmaceutically acceptable salt thereof, for use as a medicament.

14. A compound according to any one of claims 1 to 1 1 , or a pharmaceutically acceptable salt thereof, for use in the prevention or treatment of a disease selected from the group consisting of (auto-)immune/inflammatory mediated diseases, pulmonary diseases, cardiovascular diseases, infectious diseases, fibrotic disorders, neurodegenerative disorders, and tumor diseases.

15. Use of a compound according to any one of claims 1 to 1 1 , or a pharmaceutically acceptable salt thereof, for the preparation of a medicament for the prevention or treatment of a disease selected from the group consisting of (auto-)immune/inflammatory mediated diseases, pulmonary diseases, cardiovascular diseases, infectious diseases, fibrotic disorders, neurodegenerative disorders, and tumor diseases.