AZAQUINAZOLINE CXCR3 ANTAGONISTS

BACKGROUND OF THE INVENTION

Chemokines are chemotactic cytokines that are released by a wide variety of cells to attract macrophages, T cells, eosinophils, basophils and neutrophils to sites of inflammation (reviewed in Schall, Cytokine, 3:165-183 (1991), Schall, et al, Curr. Opin. Immunol., 6:865- 873 (1994) and Murphy, Rev. Immun., 12:593-633 (1994)). In addition to stimulating chemotaxis, other changes can be selectively induced by chemokines in responsive cells, including changes in cell shape, transient rises in the concentration of intracellular free calcium ions ([Ca ²⁺ ])), granule exocytosis, integrin upregulation, formation of bioactive lipids (e.g., leukotrienes) and respiratory burst, associated with leukocyte activation. Thus, the chemokines are early triggers of the inflammatory response, causing inflammatory mediator release, chemotaxis and extravasation to sites of infection or inflammation.

There are four classes of chemokines, CXC (α), CC (β), C(γ), and CX ₃ C (δ), depending on whether the first two cysteines are separated by a single amino acid (C-X-C), are adjacent (C-C), have a missing cysteine pair (C), or are separated by three amino acids (CXC ₃ ). The α- chemokines, such as interleukin-8 (IL-8), melanoma growth stimulatory activity protein (MGSA), and stromal cell derived factor 1 (SDF-I) are chemotactic primarily for neutrophils and lymphocytes, whereas β-chemokines, such as RANTES, MIP- lα, MIP-I β, monocyte chemotactic protein- 1 (MCP-I), MCP-2, MCP-3 and eotaxin are chemotactic for macrophages, T-cells, eosinophils and basophils (Deng, et al, Nature, 381:661-666 (1996)). The C chemokine lymphotactin shows specificity for lymphocytes (Kelner, et al, Science, 266:1395- 1399 (1994)) while the CX ₃ C chemokine fractalkine shows specificity for lymphocytes and monocytes (Bazan, et al, Nature, 385:640-644 (1997).

Chemokines bind specific cell-surface receptors belonging to the family of G-protein- coupled seven-transmembrane-domain proteins (reviewed in Horuk, Trends Pharm. ScL, 15:159-165 (1994)) termed "chemokine receptors." On binding their cognate ligands, chemokine receptors transduce an intracellular signal through the associated heterotrimeric G protein, resulting in a rapid increase in intracellular calcium concentration. There are at least twelve human chemokine receptors that bind or respond to β-chemokines with the following characteristic pattern: CCRl (or "CKR-I" or "CC-CKR-I") MIP-Ia, MlP-l β, MCP-3, RANTES (Ben-Barruch, et al, J. Biol Chem., 270:22123-22128 (1995); Neote, et al, Cell,

72:415-425 (1993)); CCR2A and CCR2B (or "CKR-2A"/"CKR-2A" or "CC-CKR-2A7"CC- CKR2A") MCP-I, MCP-3, MCP-4; CCR3 (or "CKR-3" or "CC-CKR-3") eotaxin, RANTES, MCP; (Ponath, et al, J. Exp. Med., 183:2437-2448 (1996)); CCR4 (or "CKR-4" or "CC-CKR- 4") TARC, MDC (Imai, et al.,. J. Biol. Chem., 273:1764-1768 (1998)); CCR5 (or "CKR-5" or "CC-CKR-5") MIP-Ia, RANTES, MIP-lβ (Sanson, et al, Biochemistry, 35:3362-3367

(1996)); CCR6 MIP-3 alpha (Greaves, et al, J. Exp. Med., 186:837-844 (1997)); CCR7 MIP-3 beta and 6Ckine (Campbell, et al, J. Cell. Biol, 141:1053-1059(1998)); CCR8 1-309, HHV8 vMIP-I, HHV-8 vMIP-II, MCV vMCC-I (Dairaghi, et al, J. Biol. Chem., 274:21569-21574 (1999)); CCR9 TECK (Zaballos, etal, J. Immunol, 162:5671-5675 (1999)), D6 MIP-I beta, RANTES, and MCP-3 (Nibbs, et al, J. Biol. Chem., 272:32078-32083 (1997)), and the Duffy blood-group antigen RANTES, MCP-I (Chaudhun, et al, J. Biol. Chem., 269:7835-7838 (1994)).

Chemokine receptors, such as CCRl, CCR2, CCR2A, CCR2B, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9, CXCRl, CXCR2, CXCR3, CXCR4, CXCR5, CX ₃ CRl, and XCRl have been implicated as being important mediators of inflammatory and immunoregulatory disorders and diseases, including asthma and allergic diseases, as well as autoimmune pathologies such as rheumatoid arthritis and atherosclerosis.

The CXCR3 chemokine receptor is expressed primarily in T lymphocytes, and its functional activity can be measured by cytosolic calcium elevation or chemotaxis. The receptor was previously referred to as GPR9 or CKR-L2. Its chromosomal location is unusual among the chemokine receptors in being localized to XqI 3. Ligands that have been identified that are selective and of high affinity are the CXC chemokines, IPlO, MIG and ITAC.

The highly selective expression of CXCR3 makes it an ideal target for intervention to interrupt inappropriate T cell trafficking. The clinical indications for such intervention are in T-cell mediated autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, and type I diabetes. Inappropriate T-cell infiltration also occurs in psoriasis and other pathogenic skin inflammation conditions, although the diseases may not be true autoimmune disorders. In this regard, up-regulation of IP-10 expression in keratinocytes is a common feature in cutaneous immunopathologies. Inhibition of CXCR3 can be beneficial in reducing rejection in organ transplantation. Ectopic expression of CXCR3 in certain tumors, especially subsets of B cell malignancies indicate that selective inhibitors of CXCR3 will have value in tumor immunotherapy, particularly attenuation of metastasis.

Certain CXCR3 inhibitors have been previously disclosed in WO02/83143, WO 04/075863, WO 06/004925, WO 06/004915, WO 06/004924 and WO 07/002701. From this

class of compounds AMG 487 was selected as the preferred compound for further testing in humans. The structure of AMG 487 is provided below:

AMG 487

Development of AMG 487, however, was halted due to dose-dependent accumulation of the compound in humans upon multiple dosing. Thus, there remains a need to identify a suitable clinical candidate devoid of the unpredicted accumulation seen with AMG 487. Such compounds are provided herein.

SUMMARY OF THE INVENTION

Evaluation of AMG 487 using human hepatocytes and microsomes led to the discovery of a minor metabolite ("M2" shown in the below scheme) that is a time-dependent inhibitor of CYP3A4. This phenolic metabolite is believed to be responsible for the accumulation of AMG 487 in humans upon multiple dosing.

M3

With the aid of this knowledge we set out to design improved compounds that are unable to undergo the metabolic activation leading to the formation of the phenolic CYP3A4 time- dependent inhibitor metabolite seen with AMG 487, while: improving (or at least maintaining) (1) potency; (2) selectivity; and (3) negative score in chromosomal aberration assay.

The present invention provides compounds which are useful in the treatment of certain inflammatory and immunoregulatory disorders and diseases, including asthma and allergic diseases, as well as autoimmune pathologies such as rheumatoid arthritis and atherosclerosis. The compounds provided herein have the general formula (I):

and salts thereof wherein R ¹ is chloro or fluoro.

Unless otherwise indicated, the compounds provided in the above formula are meant to include pharmaceutically acceptable salts and prodrugs thereof. The present invention also provides pharmaceutical compositions comprising a compound of formula I and a pharmaceutically acceptable excipient or carrier.

The present invention further provides methods for the treatment of an inflammatory or immune condition or disorder, comprising administering to a subject in need of such treatment a therapeutically effective amount of a compound of formula I. The present invention also provides methods for the treatment of a condition or disorder mediated by the CXCR3 chemokine receptor, comprising administering to a subject in need of such treatment a therapeutically effective amount of a compound of formula I.

The present invention also provides methods for the modulation of CXCR3, comprising contacting a cell with a compound of formula I. The present invention further provides methods for the modulation of CXCR3, comprising contacting a CXCR3 protein with a compound of formula I.

DETAILED DESCRIPTION OF THE INVENTION

Definitions The term "pharmaceutically acceptable salts" is meant to include salts of the active compounds which are prepared with relatively nontoxic acids or bases, depending on the particular substituents found on the compounds described herein. When compounds of the present invention contain relatively acidic functionalities, base addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired base, either neat or in a suitable inert solvent. Examples of pharmaceutically acceptable base addition salts include sodium, potassium, calcium, ammonium, organic amino, or magnesium salt, or a similar salt. When compounds of the present invention contain relatively basic functionalities, acid addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired acid, either neat or in a suitable inert solvent. Examples of pharmaceutically acceptable acid addition salts include those derived from inorganic acids like hydrochloric, hydrobromic, nitric, carbonic, monohydrogencarbonic, phosphoric, monohydrogenphosphoric, dihydrogenphosphoric, sulfuric, monohydrogensulfuric, hydriodic, or phosphorous acids and the like, as well as the salts derived from relatively nontoxic organic acids like acetic, propionic, isobutyric, maleic, malonic, benzoic, succinic, suberic, fumaric, mandelic, phthalic, benzenesulfonic, p- tolylsulfonic, citric, tartaric, methanesulfonic, and the like. Also included are salts of amino acids such as arginate and the like, and salts of organic acids like glucuronic or galactunoric acids and the like (see, for example, Berge, et al. (1977) J. Pharm. ScL 66:1-19). Certain specific compounds of the present invention contain both basic and acidic functionalities that allow the compounds to be converted into either base or acid addition salts. "Treating" or "treatment" of a disease includes:

(1) alleviating or abrogating a disease and/or its attendant symptoms,

(2) barring a subject from acquiring a disease

(3) reducing a subject's risk of acquiring a disease, (4) decreasing the probability or eliminating the possibility that a disease will be contracted,

(5) preventing the disease, i.e., causing the clinical symptoms of the disease not to develop in a mammal that may be exposed to or predisposed to the disease but does not yet experience or display symptoms of the disease,

(6) inhibiting the disease, i.e., arresting or reducing the development of the disease or its clinical symptoms, or

(7) relieving the disease, i.e., causing regression of the disease or its clinical symptoms. The neutral forms of the compounds may be regenerated by contacting the salt with a base or acid and isolating the parent compound in the conventional manner. The parent form of the compound differs from the various salt forms in certain physical properties, such as solubility in polar solvents, but otherwise the salts are equivalent to the parent form of the compound for the purposes of the present invention. In addition to salt forms, the present invention provides compounds which are in a prodrug form. Prodrugs of the compounds described herein are those compounds that readily undergo chemical changes under physiological conditions to provide the compounds of the present invention. Additionally, prodrugs can be converted to the compounds of the present invention by chemical or biochemical methods in an ex vivo environment. For example, prodrugs can be slowly converted to the compounds of the present invention when placed in a transdermal patch reservoir with a suitable enzyme or chemical reagent. Prodrugs are often useful because, in some situations, they may be easier to administer than the parent drug. They may, for instance, be bioavailable by oral administration whereas the parent drug is not. The prodrug may also have improved solubility in pharmacological compositions over the parent drug. A wide variety of prodrug derivatives are known in the art, such as those that rely on hydrolytic cleavage or oxidative activation of the prodrug. An example, without limitation, of a prodrug would be a compound of the present invention which is administered as an ester (the "prodrug"), but then is metabolically hydrolyzed to the carboxylic acid, the active entity. Additional examples include peptidyl derivatives of a compound of the invention. Certain compounds of the present invention can exist in unsolvated forms as well as solvated forms, including hydrated forms. In general, the solvated forms are equivalent to unsolvated forms and are intended to be encompassed within the scope of the present invention. Certain compounds of the present invention may exist in multiple crystalline or amorphous forms. In general, all physical forms are equivalent for the uses contemplated by the present invention and are intended to be within the scope of the present invention.

Certain compounds of the present invention possess asymmetric carbon atoms (optical centers) or double bonds; the racemates, diastereomers, geometric isomers and individual isomers are all intended to be encompassed within the scope of the present invention.

The compounds of the present invention may also contain unnatural proportions of atomic isotopes at one or more of the atoms that constitute such compounds. For example, the compounds may be radiolabeled with radioactive isotopes, such as for example tritium ( ³ H), iodine-125 ( ¹²⁵ I) or carbon-14 ( ¹⁴ C). Radiolabled compounds are useful as therapeutic agents, e.g., cancer therapeutic agents, research reagents, e.g., binding assay reagents, and diagnostic agents, e.g., in vivo imaging agents. All isotopic variations of the compounds of the present invention, whether radioactive or not, are intended to be encompassed within the scope of the present invention.

Embodiments of the Invention

The present invention is directed to compounds, compositions and methods useful in the modulation of chemokine receptor activity, particularly CXCR3. Accordingly, the compounds of the present invention are those which inhibit at least one function or characteristic of a mammalian CXCR3 protein, for example, a human CXCR3 protein. The ability of a compound to inhibit such a function can be demonstrated in a binding assay (e.g., ligand binding or agonist binding), a signalling assay (e.g., activation of a mammalian G protein, induction of rapid and transient increase in the concentration of cytosolic free calcium), and/or cellular response function (e.g., stimulation of chemotaxis, exocytosis or inflammatory mediator release by leukocytes).

Compounds

The present invention provides compounds that are useful as antagonists of CXCR3, having particular utility for the treatment of inflammation. The compounds provided herein have the general formula (I):

and salts thereof wherein R ¹ is chloro or fluoro.

Compositions

In another aspect, the present invention provides pharmaceutical compositions for modulating chemokine receptor activity in humans and animals. The compositions comprise a compound of the present invention with a pharmaceutically acceptable carrier or diluent. "Modulation" or modulating of chemokine receptor activity, as used herein in its various forms, is intended to encompass antagonism, agonism, partial antagonism and/or partial agonism of the activity associated with a particular chemokine receptor, preferably the CXCR3 receptor. The term "composition" as used herein is intended to encompass a product comprising the specified ingredients (and in the specified amounts, if indicated), as well as any product which results, directly or indirectly, from combination of the specified ingredients in the specified amounts. By "pharmaceutically acceptable" it is meant the carrier, diluent or excipient must be compatible with the other ingredients of the formulation and not deleterious to the recipient thereof.

The pharmaceutical compositions for the administration of the compounds of this invention may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. All methods include the step of bringing the active ingredient into association with the carrier which constitutes one or more accessory ingredients. In general, the pharmaceutical compositions are prepared by uniformly and intimately bringing the active ingredient into association with a liquid carrier or a finely divided solid carrier or both, and then, if necessary, shaping the product into the desired formulation. In the pharmaceutical composition the active object compound is included in an amount sufficient to produce the desired effect upon the process or condition of diseases. The pharmaceutical compositions containing the active ingredient may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Compositions intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of sweetening agents, flavoring agents, coloring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets contain the active ingredient in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of tablets. These excipients may be, for example, inert diluents, such as calcium carbonate, sodium

carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example, corn starch, or alginic acid; binding agents, for example starch, gelatin or acacia, and lubricating agents, for example magnesium stearate, stearic acid or talc. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed. They may also be coated by the techniques described in U.S. Pat. Nos. 4,256,108; 4,166,452 and 4,265,874 to form osmotic therapeutic tablets for control release. Formulations for oral use may also be presented as hard gelatin capsules wherein the active ingredient is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example peanut oil, liquid paraffin, or olive oil.

Aqueous suspensions contain the active materials in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydroxy-propylmethylcellulose, sodium alginate, polyvinyl-pyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be a naturally-occurring phosphatide, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxy-ethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example polyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives, for example ethyl, or n-propyl, p-hydroxybenzoate, one or more coloring agents, one or more flavoring agents, and one or more sweetening agents, such as sucrose or saccharin.

Oily suspensions may be formulated by suspending the active ingredient in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin. The oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set forth above, and flavoring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an anti-oxidant such as ascorbic acid.

Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting

agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional excipients, for example sweetening, flavoring and coloring agents, may also be present.

The pharmaceutical compositions of the invention may also be in the form of oil-in- water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oil, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally-occurring gums, for example gum acacia or gum tragacanth, naturally- occurring phosphatides, for example soy bean, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan monooleate, and condensation products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening and flavoring agents.

Syrups and elixirs may be formulated with sweetening agents, for example glycerol, propylene glycol, sorbitol or sucrose. Such formulations may also contain a demulcent, a preservative and flavoring and coloring agents. The pharmaceutical compositions may be in the form of a sterile injectable aqueous or oleagenous suspension. This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example as a solution in 1,3- butane diol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil may be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid find use in the preparation of injectables. The compounds of the present invention may also be administered in the form of suppositories for rectal administration of the drug. These compositions can be prepared by mixing the drug with a suitable non-irritating excipient which is solid at ordinary temperatures but liquid at the rectal temperature and will therefore melt in the rectum to release the drug. Such materials are cocoa butter and polyethylene glycols. For topical use, creams, ointments, jellies, solutions or suspensions, etc., containing the compounds of the present invention are employed. As used herein, topical application is also meant to include the use of mouth washes and gargles.

The pharmaceutical composition and method of the present invention may further comprise other therapeutically active compounds as noted herein which are usually applied in the treatment of the above mentioned pathological conditions.

Methods of Use

In yet another aspect, the present invention provides methods of treating CXCR3- mediated conditions or diseases by administering to a subject having such a disease or condition, a therapeutically effective amount of a compound or composition of the invention. The "subject" is defined herein to include animals such as mammals, including , but not limited to, primates (e.g., humans), cows, sheep, goats, horses, dogs, cats, rabbits, rats, mice and the like.

As used herein, the phrase "CXCR3-mediated condition or disease" and related phrases and terms refer to a condition characterized by inappropriate, e.g., less than or greater than normal, CXCR3 activity. Inappropriate CXCR3 activity might arise as the result of CXCR3 expression in cells which normally do not express CXCR3, increased CXCR3 expression (leading to, e.g., inflammatory and immunoregulatory disorders and diseases), or, decreased CXCR3 expression (leading to, e.g., certain cancers and angiogenic and vasculogenic-related disorders). Inappropriate CXCR3 functional activity might arise as the result of CXCR3 expression in cells which normally do not express CXCR3, increased CXCR3 expression (leading to, e.g., inflammatory and immunoregulatory disorders and diseases) or decreased

CXCR3 expression. Inappropriate CXCR3 functional activity might also arise as the result of chemokine secretion by cells which normally do not secrete a CXC chemokine, increased chemokine expression (leading to, e.g., inflammatory and immunoregulatory disorders and diseases) or decreased chemokine expression. A CXCR3 -mediated condition or disease may be completely or partially mediated by inappropriate CXCR3 functional activity. However, a CXCR3 -mediated condition or disease is one in which modulation of CXCR3 results in some effect on the underlying condition or disease (e.g., a CXCR3 antagonist results in some improvement in patient well-being in at least some patients).

The term "therapeutically effective amount" means the amount of the subject compound that will elicit the biological or medical response of a tissue, system, animal or human that is being sought by the researcher, veterinarian, medical doctor or other clinician or that is sufficient to prevent development of or alleviate to some extent one or more of the symptoms of the disease being treated.

Diseases and conditions associated with inflammation, infection and cancer can be treated with the present compounds and compositions. In one group of embodiments, diseases or conditions, including chronic diseases, of humans or other species can be treated with inhibitors of CXCR3 function. These diseases or conditions include: (1) inflammatory or allergic diseases such as systemic anaphylaxis or hypersensitivity responses, drug allergies, insect sting allergies and food allergies; inflammatory bowel diseases, such as Crohn's disease, ulcerative colitis, ileitis and enteritis; vaginitis; psoriasis and inflammatory dermatoses such as dermatitis, eczema, atopic dermatitis, allergic contact dermatitis, urticaria; vasculitis; spondyloarthropathies; scleroderma; asthma and respiratory allergic diseases such as allergic rhinitis, hypersensitivity lung diseases, and the like, (2) autoimmune diseases, such as arthritis (rheumatoid and psoriatic), multiple sclerosis, systemic lupus erythematosus, type I diabetes, glomerulonephritis, and the like, (3) graft rejection (including allograft rejection and graft-v- host disease) and conditions associated therewith, and (4) other diseases in which undesired inflammatory responses are to be inhibited, e.g., atherosclerosis, myositis, neurodegenerative diseases (e.g., Alzheimer's disease), encephalitis, meningitis, hepatitis, nephritis, sepsis, sarcoidosis, conjunctivitis, otitis, chronic obstructive pulmonary disease, sinusitis and Behcet's syndrome. In another group of embodiments, diseases or conditions are treated with agonists of CXCR3 function. Examples of diseases to be treated with CXCR3 agonists include cancers, diseases in which angiogenesis or neovascularization play a role (neoplastic diseases, retinopathy and macular degeneration), infectious diseases and immunosuppressive diseases. Preferably, the present methods are directed to the treatment of diseases or conditions selected from neurodegenerative diseases (e.g., Alzheimer's disease), multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, atherosclerosis, encephalitis, meningitis, hepatitis, nephritis, sepsis, sarcoidosis, psoriasis, eczema, uticaria, type I diabetes, asthma, conjunctivitis, otitis, allergic rhinitis, chronic obstructive pulmonary disease, sinusitis, dermatitis, inflammatory bowel disease, ulcerative colitis, Crohn's disease, Behcet's syndrome, gout, cancer, viral infections (e.g., HFV), bacterial infections, and organ transplant conditions or skin transplant conditions. The term "organ transplant conditions" is meant to include bone marrow transplant conditions and solid organ (e.g., kidney, liver, lung, heart, pancreas or combination thereof) transplant conditions.

Diseases or conditions that can be treated with the present compounds and compositions include diseases commonly associated with (1) inflammatory or allergic diseases, (2) autoimmune diseases, (3) graft rejection and (4) other diseases in which undesired inflammatory responses are to be inhibited, as described above. For example, restenosis

following a procedure such as balloon angioplasty, is commonly associated with atherosclerosis and can be treated with the present compounds and compositions.

Depending on the disease to be treated and the subject's condition, the compounds of the present invention may be administered by oral, parenteral (e.g., intramuscular, intraperitoneal, intravenous, ICV, intracisternal injection or infusion, subcutaneous injection, or implant), inhalation spray, nasal, vaginal, rectal, sublingual, or topical routes of administration and may be formulated, alone or together, in suitable dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles appropriate for each route of administration. In the treatment of conditions which require chemokine receptor modulation an appropriate dosage level will generally be about 0.001 to 100 mg per kg patient body weight per day which can be administered in single or multiple doses. Preferably, the dosage level will be about 0.01 to about 25 mg/kg per day; more preferably about 0.05 to about 10 mg/kg per day. A suitable dosage level may be about 0.01 to 25 mg/kg per day, about 0.05 to 10 mg/kg per day, or about 0.1 to 5 mg/kg per day. Within this range the dosage may be 0.005 to 0.05, 0.05 to 0.5 or 0.5 to 5.0 mg/kg per day. For oral administration, the compositions are preferably provided in the form of tablets containing 1.0 to 1000 milligrams of the active ingredient, particularly 1.0, 5.0, 10.0, 15.0. 20.0, 25.0, 50.0, 75.0, 100.0, 150.0, 200.0, 250.0, 300.0, 400.0, 500.0, 600.0, 750.0, 800.0, 900.0, and 1000.0 milligrams of the active ingredient for the symptomatic adjustment of the dosage to the patient to be treated. The compounds may be administered on a regimen of 1 to 4 times per day, preferably once or twice per day.

It will be understood, however, that the specific dose level and frequency of dosage for any particular patient may be varied and will depend upon a variety of factors including the activity of the specific compound employed, the metabolic stability and length of action of that compound, the age, body weight, general health, sex, diet, mode and time of administration, rate of excretion, drug combination, the severity of the particular condition, and the host undergoing therapy.

The compounds of the present invention can be combined with other compounds having related utilities to treat inflammatory and immune disorders and diseases, including asthma and allergic diseases, as well as autoimmune pathologies such as rheumatoid arthritis and atherosclerosis, and those pathologies noted above. In many instances, compositions which include a compound of the invention and an alternative or second therapeutic agent have additive or synergistic effects when administered.

For example, in the treatment of inflammation, the present compounds may be used in conjunction or combination with an antiinflammatory or analgesic agent such as an opiate agonist, a lipoxygenase inhibitor, such as an inhibitor of 5 -lipoxygenase, a cyclooxygenase inhibitor, such as a cyclooxygenase-2 inhibitor, an interleukin inhibitor, such as an interleukin- 1 inhibitor, an NMDA antagonist, an inhibitor of nitric oxide or an inhibitor of the synthesis of nitric oxide, a non-steroidal antiinflammatory agent, or a cytokine-suppressing antiinflammatory agent, for example with a compound such as acetaminophen, aspirin, codiene, fentanyl, ibuprofen, indomethacin, ketorolac, morphine, naproxen, phenacetin, piroxicam, a steroidal analgesic, sufentanyl, sunlindac, tenidap, and the like. Similarly, the instant compounds may be administered with a pain reliever; a potentiator such as caffeine, an H2-antagonist, simethicone, aluminum or magnesium hydroxide; a decongestant such as phenylephrine, phenylpropanolamine, pseudophedrine, oxymetazoline, epinephrine, naphazoline, xylometazoline, propylhexedrine, or levo-desoxy-ephedrine; an antiitussive such as codeine, hydrocodone, caramiphen, carbetapentane, or dextromethorphan; a diuretic; and a sedating or non-sedating antihistamine. Likewise, compounds of the present invention may be used in combination with other drugs that are used in the treatment/prevention/suppression or amelioration of the diseases or conditions for which compounds of the present invention are useful. Such other drugs may be administered, by a route and in an amount commonly used therefor, contemporaneously or sequentially with a compound of the present invention. When a compound of the present invention is used contemporaneously with one or more other drugs, a pharmaceutical composition containing such other drugs in addition to the compound of the present invention is preferred. Accordingly, the pharmaceutical compositions of the present invention include those that also contain one or more other active ingredients, in addition to a compound of the present invention. Examples of other active ingredients that may be combined with a compound of the present invention, either administered separately or in the same pharmaceutical compositions, include, but are not limited to: (a) VLA-4 antagonists, (b) steroids such as beclomethasone, methylprednisolone, betamethasone, prednisone, dexamethasone, and hydrocortisone; (c) immunosuppressants such as cyclosporine (cyclosporine A, Sandimmune®, Neoral®), tacrolimus (FK-506, Prograf®), rapamycin (sirolimus, Rapamune®) and other FK-506 type immunosuppressants, and mycophenolate, e.g., mycophenolate mofetil (CellCept®); (d) antihistamines (Hl -histamine antagonists) such as bromopheniramine, chlorpheniramine, dexchlorpheniramine, triprolidine, clemastine, diphenhydramine, diphenylpyraline, tripelennamine, hydroxyzine, methdilazine, promethazine, trimeprazine, azatadine, cyproheptadine, antazoline, pheniramine pyrilamine, astemizole,

terfenadine, loratadine, cetirizine, fexofenadine, descarboethoxyloratadine, and the like; (e) non-steroidal anti-asthmatics such as .beta.2-agonists (terbutaline, metaproterenol, fenoterol, isoetharine, albuterol, bitolterol, and pirbuterol), theophylline, cromolyn sodium, atropine, ipratropium bromide, leukotriene antagonists (zafirlukast, montelukast, pranlukast, iralukast, pobilukast, SKB-106,203), leukotriene biosynthesis inhibitors (zileuton, BAY-1005); (f) nonsteroidal antiinflammatory agents (NSAIDs) such as propionic acid derivatives (alminoprofen, benoxaprofen, bucloxic acid, carprofen, fenbufen, fenoprofen, fluprofen, flurbiprofen, ibuprofen, indoprofen, ketoprofen, miroprofen, naproxen, oxaprozin, pirprofen, pranoprofen, suprofen, tiaprofenic acid, and tioxaprofen), acetic acid derivatives (indomethacin, acemetacin, alclofenac, clidanac, diclofenac, fenclofenac, fenclozic acid, fentiazac, furofenac, ibufenac, isoxepac, oxpinac, sulindac, tiopinac, tolmetin, zidometacin, and zomepirac), fenamic acid derivatives (flufenamic acid, meclofenamic acid, mefenamic acid, niflumic acid and tolfenamic acid), biphenylcarboxylic acid derivatives (diflunisal and flufenisal), oxicams (isoxicam, piroxicam, sudoxicam and tenoxican), salicylates (acetyl salicylic acid, sulfasalazine) and the pyrazolones (apazone, bezpiperylon, feprazone, mofebutazone, oxyphenbutazone, phenylbutazone); (g) cyclooxygenase-2 (COX-2) inhibitors such as celecoxib (Celebrex®) and rofecoxib (Vioxx®); (h) inhibitors of phosphodiesterase type IV (PDE-IV); (i) gold compounds such as auranofin and aurothio glucose, (j) inhibitors of phosphodiesterase type IV (PDE-IV); (k) other antagonists of the chemokine receptors, especially CCRl, CCR2, CCR3, CCR5, CCR6, CCR8 and CCRl 0; (1) cholesterol lowering agents such as HMG-CoA reductase inhibitors (lovastatin, simvastatin and pravastatin, fluvastatin, atorvastatin, and other statins), sequestrants (cholestyramine and colestipol), nicotinic acid, fenofibric acid derivatives (gemfibrozil, clofibrat, fenofϊbrate and benzafibrate), and probucol; (m) anti-diabetic agents such as insulin, sulfonylureas, biguanides (metformin), α-glucosidase inhibitors (acarbose) and glitazones (troglitazone and pioglitazone); (n) preparations of interferon beta (interferon β-1 α, interferon β -1 β); (o) etanercept (Enbrel®), (p) antibody therapies such as orthoclone (OKT3), daclizumab (Zenapax®) , infliximab (Remicade®), basiliximab (Simulect®) and anti-CD40 ligand antibodies (e.g., MRP-I); and (q) other compounds such as 5-aminosalicylic acid and prodrugs thereof, hydroxychloroquine, D-penicillamine, antimetabolites such as azathioprene and 6-mercaptopurine, and cytotoxic cancer chemotherapeutic agents. The weight ratio of the compound of the present invention to the second active ingredient may be varied and will depend upon the effective dose of each ingredient. Generally, an effective dose of each will be used. Thus, for example, when a compound of the present invention is combined with an NSAID the weight ratio of the compound of the present invention to the NSAID will generally

range from about 1000:1 to about 1 :1000, preferably about 200:1 to about 1:200. Combinations of a compound of the present invention and other active ingredients will generally also be within the aforementioned range, but in each case, an effective dose of each active ingredient should be used. Immunosuppressants within the scope of the present invention further include, but are not limited to, leflunomide, RADOOl, ERL080, FTY720, CTLA-4, antibody therapies such as orthoclone (OKT3), daclizumab (Zenapax®) and basiliximab (Simulect®), and antithymocyte globulins such as thymoglobulins.

In particularly preferred embodiments, the present methods are directed to the treatment of multiple sclerosis using a compound of the invention either alone or in combination with a second therapeutic agent selected from betaseron, avonex, azathioprene (Imurek®, Imuran®), capoxone, prednisolone and cyclophosphamide. When used in combination, the practitioner can administer a combination of the therapeutic agents, or administration can be sequential. In still other particularly preferred embodiments, the present methods are directed to the treatment of rheumatoid arthritis, wherein the compound of the invention is administered either alone or in combination with a second therapeutic agent selected from the group consisting of methotrexate, sulfasalazine, hydroxychloroquine, cyclosporine A, D- penicillamine, infliximab (Remicade®), etanercept (Enbrel®), auranofin and aurothioglucose. In yet other particularly preferred embodiments, the present methods are directed to the treatment of an organ transplant condition wherein the compound of the invention is used alone or in combination with a second therapeutic agent selected from the group consisting of cyclosporine A, FK-506, rapamycin, mycophenolate, prednisolone, azathioprene, cyclophosphamide and an antilymphocyte globulin.

In yet another aspect, the present invention includes methods to evaluate putative specific agonists or antagonists of CXCR3 function. Accordingly, the present invention is directed to the use of these compounds in the preparation and execution of screening assays for compounds which modulate the activity of the CXCR3 chemokine receptor. For example, the compounds of this invention are useful for isolating receptor mutants, which are excellent screening tools for more potent compounds. Furthermore, the compounds of this invention are useful in establishing or determining the binding site of other compounds to the CXCR3 chemokine receptor, e.g., by competitive inhibition. The compounds of the instant invention are also useful for the evaluation of putative specific modulators of the CXCR3 chemokine receptor, relative to other chemokine receptors including CCRl, CCR2, CCR2A, CCR2B, CCR3, CCR4, CCR5, CCR6, CCR8, CCRlO, CXCR3 and CXCR4. One of skill in the art will

appreciate that thorough evaluation of specific agonists and antagonists of the above chemokine receptors has been hampered by the lack of availability of non-peptidyl (metabolically resistant) compounds with high binding affinity for these receptors. Thus the compounds provided herein are particularly useful in this context. Combinatorial libraries of putative CXCR3 agonists or antagonists can be screened for pharmacological activity in in vitro or in vivo assays. Conventionally, new chemical entities with useful properties are generated by identifying a chemical compound (called a "lead compound") with some desirable property or activity, e.g., CXCR3 chemokine receptor modulation activity, creating variants of the lead compound, and evaluating the property and activity of those variant compounds. However, the current trend is to shorten the time scale for all aspects of drug discovery. Because of the ability to test large numbers quickly and efficiently, high throughput screening (HTS) methods are replacing conventional lead compound identification methods. In one preferred embodiment, high throughput screening methods involve providing a library containing a large number of potential therapeutic compounds (candidate compounds). Such "combinatorial chemical libraries" are then screened in one or more assays to identify those library members (particular chemical species or subclasses) that display a desired characteristic activity. The compounds thus identified can serve conventional "lead compounds" or can themselves be used as potential or actual therapeutics.

A combinatorial chemical library is a collection of diverse chemical compounds generated by either chemical synthesis or biological synthesis by combining a number of chemical "building blocks" such as reagents. For example, a linear combinatorial chemical library, such as a polypeptide (e.g., mutein) library, is formed by combining a set of chemical building blocks called amino acids in every possible way for a given compound length (i.e., the number of amino acids in a polypeptide compound). Millions of chemical compounds can be synthesized through such combinatorial mixing of chemical building blocks (Gallop et. al. (1994) J. Med. Chem. 37(9):1233-1251).

Preparation and screening of combinatorial chemical libraries is well known to those of skill in the art. Such combinatorial chemical libraries include, but are not limited to, peptide libraries (see, e.g., U.S. Patent No. 5,010,175, Furka (1991) Int. J. Pept. Prot. Res. 37:487-493, Houghton et. al (1991) Nature 354: 84-88), peptoid libraries (PCT Publication No WO

91/19735), encoded peptide libraries (PCT Publication WO 93/20242), random bio-oligomer libraries (PCT Publication WO 92/00091), benzodiazepine libraries (U.S. Patent No. 5,288,514), libraries of diversomers, such as hydantoins, benzodiazepines and dipeptides (Hobbs et. al (\993) Proc. Nat. Acad. ScL USA 90:6909-6913), vinylogous polypeptide

libraries (Hagihara et al. (1992) J. Amer. Chem. Soc. 114:6568), libraries of nonpeptidyl peptidomimetics with a Beta-D-Glucose scaffolding (Hirschmann et al (1992) J. Amer. Chem. Soc. 114:9217-9218), analogous organic syntheses of small compound libraries (Chen et. al. (1994) J. Am. Chem. Soc. 116:2661), oligocarbamate libraries (Cho et al. (1993) Science 261 : 1303) and/or peptidyl phosphonate libraries (Campbell et al. (1994) J. Org. Chem. 59:658). See, generally, Gordon et al. (1994) J. Med. Chem. 37:1385-1401, nucleic acid libraries (see, e.g., Stratagene Corp.), peptide nucleic acid libraries (see, e.g., U.S. Patent No. 5,539,083), antibody libraries (see, e.g., Vaughn et. al. (1996) Nature Biotechnology 14(3):309-314), and PCT/US96/10287), carbohydrate libraries (see, e.g., Liang et al. (1996) Science 274:1520-1522, and U.S. Patent No. 5,593,853), and small organic molecule libraries (see, e.g., benzodiazepines, Baum (1993) C&EN Jan 18, page 33; isoprenoids, U.S. Patent No. 5,549,974; pyrrolidines, U.S. Patent Nos. 5,525,735 and 5,519,134; morpholino compounds, U.S. Patent No. 5,506,337; benzodiazepines, U.S. Patent No. 5,288,514; and the like).

Devices for the preparation of combinatorial libraries are commercially available (see, e.g., 357 MPS, 390 MPS, Advanced Chem Tech, Louisville KY; Symphony, Rainin, Woburn MA; 433A Applied Biosystems, Foster City CA; 9050 Plus, Millipore, Bedford, MA).

A number of well known robotic systems have also been developed for solution phase chemistries. These systems includes automated workstations like the automated synthesis apparatus developed by Takeda Chemical Industries, LTD. (Osaka, Japan) and many robotic systems utilizing robotic arms (Zymate II, Zymark Corporation, Hopkinton MA; Orca,

Hewlett-Packard, Palo Alto CA), which mimic the manual synthetic operations performed by a chemist. Any of the above devices are suitable for use with the present invention. The nature and implementation of modifications to these devices (if any) so that they can operate as discussed herein will be apparent to persons skilled in the relevant art. In addition, numerous combinatorial libraries are themselves commercially available (see e.g., ComGenex, Princeton NJ; Asinex, Moscow, Russia; Tripos, Inc., St. Louis MO; ChemStar, Ltd, Moscow, Russia; 3D Pharmaceuticals, Exton PA; Martek Biosciences, Columbia MD; etc.).

High throughput assays for the presence, absence, quantification, or other properties of particular compounds may be used to test a combinatorial library that contains a large number of potential therapeutic compounds (potential modulator compounds). The assays are typically designed to screen large chemical libraries by automating the assay steps and providing compounds from any convenient source to assays, which are typically run in parallel (e.g., in microtiter formats on microtiter plates in robotic assays). Preferred assays detect enhancement or inhibition of CXCR3 receptor function.

High throughput screening systems are commercially available (see e.g., Zymark Corp., Hopkinton MA; Air Technical Industries, Mentor OH; Beckman Instruments, Inc., Fullerton CA; Precision Systems, Inc., Natick MA; etc.). These systems typically automate entire procedures, including all sample and reagent pipetting, liquid dispensing, timed incubations, and final readings of the microplate in detector(s) appropriate for the assay. These configurable systems provide high throughput and rapid start up as well as a high degree of flexibility and customization. The manufacturers of such systems provide detailed protocols for various high throughput systems. Thus, for example, Zymark Corp. provides technical bulletins describing screening systems for detecting the modulation of gene transcription, ligand binding, and the like.

EXAMPLES Example 1

Scheme:

Example compound 1 NMR:

IH NMR (400 MHz, CHLOROFORM-J) (Compound exists as a mixture of conformational isomers) δ ppm 1.43 (d, J=7.04 Hz, 3 H) 1.65 (d, J=6.65 Hz, 1 H) 1.77 - 2.05 (m, 8 H) 2.05 - 2.14 (m, 1 H) 2.45 - 2.59 (m, 1 H) 2.80 (d, J=12.91 Hz, 1 H) 2.96 - 3.25 (m, 3 H) 3.46 (dd, 1 H) 3.56 (dd, 1 H) 3.65 - 3.76 (m, 1 H) 3.78 (s, 2 H) 4.95 (q, J=7.17 Hz, 1 H) 6.97 - 7.07 (m, 2 H) 7.21 (dd, J=SAl, 2.54 Hz, 1 H) 7.44 (dd, J=7.83, 4.69 Hz, 1 H) 7.48 - 7.61 (m, 3 H) 7.75 (dd, J=8.41, 2.54 Hz, 1 H) 8.57 (dd, J=7.83, 1.96 Hz, 1 H) 8.94 (dd, J=4.30, 1.96 Hz, 1 H); Analytical HPLC Method A @ 254 nm: rt = 8.448 min.; ESI (MH ⁺ ) m/z 651.

Example 2

Example compound 2 can be made according to a procedure similar to that described in Example 1.

Example compound 1 NMR:

IH NMR (500 MHz, CHLOROFORM-^) (Compound exists as a mixture of conformational isomers) δ ppm 1.46 (d, J=I.34 Hz, 3 H) 1.60 - 1.68 (m, 2 H) 1.87 - 2.08 (m, 1 H) 2.08 - 2.17 (m, 1 H) 2.83 (d, J=12.72 Hz, 1 H) 3.05 - 3.27 (m, 2 H) 3.44 - 3.53 (m, 1 H) 3.54 - 3.63 (m, 1 H) 3.68 - 3.78 (m, 1 H) 3.81 (s, 2 H) 5.00 (q, J=7.50 Hz, 1 H) 6.99 - 7.11 (m, 2 H) 7.22 - 7.28 (m, 2 H) 7.32 (t, J=7.70 Hz, 1 H) 7.47 (dd, J=7.83, 4.65 Hz, 1 H) 7.54 (t, J=7.70 Hz, 1 H) 7.79 - 7.87 (m, J=I 0.52, 4.40 Hz, 1 H) 8.60 (dd, J=7.95, 1.83 Hz, 1 H) 8.97 (dd, J=4.65, 1.96 Hz, 1 H); Analytical HPLC Method A @ 254 nm: rt = 8.107 min.; ESI (MH ⁺ ) m/z 635.

Example 3

This example illustrates a CXCR3 binding assay that can be used for evaluating the compounds of the present invention.

Unless otherwise noted, all reagents used are available from commercial sources (e.g., Sigma). Test compounds are diluted in DMSO to a concentration that is 40-times the intended final assay concentration; 5 μL are transferred to each well of a 96-well flat-bottomed polypropylene plate (e.g., from Greiner, Inc.). CXCR3 -expressing cells obtained from ChemoCentryx were used in the assays to generate the data set forth in the Table provided in Figure 12. The cells were resuspended in assay buffer (25 mM Hepes, 80 mM NaCl, 1 raM CaCl ₂ , 5 mM MgCl ₂ , 0.2% bovine serum albumin, pH 7.1, stored at 4 ⁰ C) at 5 million cells per mL; 100 μL of this cell suspension is then transferred to each well of a 96-well plate containing the diluted test compounds. ^l25 I-labelled chemokine (purchased from commercial

sources, e.g., Amersham, PE Life Sciences) is diluted in assay buffer to a concentration of approximately 60 pM; 100 μL of this chemokine solution is transferred to each well of a 96- well plate containing compounds and cell suspension. The plates are sealed with commercially available foil plate seals (e.g., from E&K Scientific), and stored at 4 ⁰ C for 2 to 4 h, shaking gently. At the end of this incubation period, the contents of the assay plates are transferred to GF/B filter plates (Packard) that have been pre-coated by dipping into a solution containing 0.3% polyethyleneimine (Sigma), using a cell harvester (Packard), and washing twice with wash buffer (25 mM Hepes, 500 mM NaCl, 1 mM CaCl ₂ , 5 mM MgCl ₂ , pH 7.1 , stored at room temperature). The filter plates are sealed on the bottom with plate seals (Packard), 50 μL of Microscint-20 scintillation fluid (Packard) is added to each well, and the top of the plates are sealed with clear plastic (TopSeal A, Packard). The plates are counted on a scintillation counter, such as a Packard TopCount. To measure non-specific binding, 4 wells containing unlabelled "cold" chemokine were included on each 96-well plate. To measure maximum binding, 4 wells containing 5 μL of DMSO, 100 μL of cell suspension and 100 μL of ¹²⁵ I- labelled chemokine solution were included on each 96-well plate. Data were analyzed using commercially available software (e.g., Excel from Microsoft, Prism from GraphPad Software Inc.).

Other assays may be used to identify compounds that modulate CXCR3 chemokine receptor activity, for example, binding assays (see, e.g., Weng et al. (1998) J. Biol. Chem. 273:18288-18291, Campbell et al. (1998) J. Cell Biol. 141:1053-1059, Endres et al. (1999) J. Exp. Med. 189:1993-1998 and Ng et al. (1999) J. Med. Chem. 42:4680-4694), calcium flux assays (see, e.g., Wang et al. (2000) MoI. Pharm.. 57:1190-1198 and Rabin et al. (1999j J. Immunol. 162:3840-3850) and chemotaxis assays (see, e.g., Albanesi et al. (2000) J. Immunol. 165:1395-1402 and Loetscher et al. (1998; Eur. J. Immunol. 28:3696-3705). The compounds exemplified herein have been tested in biological assays and were found to inhibit CXCR3. For example, compound 1 inhibits binding of ¹²⁵ I-IP-IO and ¹²⁵ I-I- TAC to primary, activated human lymphocytes. The concentration of example compound 1 required for 50% inhibition of ¹²⁵ I-IP-IO and ¹²⁵ I-I-TAC (the IC ₅₀ ) in 50% human plasma is 12 ± 5 nM and 51 ± 20 nM respectively. Example compound 1 is also a potent inhibitor of lymphocyte migration toward I-TAC (ICs ₀ = 65 ± 14 nM) in 100% human plasma. The following table compares the potencies of AMG 487 with that of compound 1 :

Figure 1 illustrates that compound 1 inhibits cellular migration into the lung following bleomycin challenge.

All publications and patent applications cited in this specification are herein incorporated by reference as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims.