H4 antagonist compounds

Abstract

The present disclosure relates to azetidinyl pyrimidine-2-amine derivatives, their use as histamine H4 receptor antagonists, and their use in treating, preventing, ameliorating, controlling or reducing the risk of disorders associated with the H4 receptor.

Description

[0001] The present application relates to novel compounds and their use as histamine H4 receptor antagonists. The compounds described herein can be used to treat or prevent diseases in which the H4 receptor is involved. The present application also relates to pharmaceutical compositions containing these compounds, as well as the manufacture of these compounds and compositions and their use in preventing or treating such diseases in which the H4 receptor is involved. Background of the Invention

[0003] Histamine is a short-acting biogenic amine produced in mast cells. In mast cells, histamine is stored in cytoplasmic granules and is released in response to multiple immune stimulation and non-immune stimulation. The histamine release from mast cells has traditionally been associated with mild to serious signs and symptoms, which are characterized by allergic reactions, including erythema, urticaria, itching, tachycardia, hypotension, ventricular fibrillation, bronchospasm and cardiac and respiratory arrest. So far, many other sources have been identified, including basophils, neurons and cancer cells. Except for regulating a wide range of physiological processes, histamine is also relevant to pathological conditions, which include allergies and anaphylaxis, asthma and chronic inflammation, autoimmune disorders, cardiovascular disorders, neuropsychiatric disorders and endocrine disorders and cancer.

[0004] Histamine exerts its pleiotropic effects primarily by binding to four types of G protein-coupled receptors (GPCRs), designated H1-H4, which are differentially expressed in different cell types and show considerable variation among species. H2 receptors are responsible for gastric acid secretion; H3 receptors control the release of histamine and other neuromodulators in the CNS, and H1 receptors are associated with arousal and inflammatory responses.

[0005] The high-affinity H4 receptor, identified in 2000, displays constitutive activity and is primarily, but not exclusively, expressed on cells of the immune system, including mast cells, monocytes, dendritic cells, eosinophils, basophils, neutrophils, and T cells. This discovery offers the attractive prospect of a new drug target with therapeutic potential in acute and chronic inflammation, autoimmune diseases, host defense, and neuropathic pain.

[0006] H4R shares only 40% homology with its nearest neighbor H3R, and neither H2 nor H1 antagonists have been shown to inhibit histamine-induced eosinophil chemotaxis. Histamine has been shown to inhibit forskolin-induced cAMP responses in a pertussis toxin (PTx)-sensitive manner, suggesting that H4R signaling is via heterotrimeric Gαi / o proteins. Transient expression of H4R in heterologous cell systems (e.g., HEK293 cells) is a widely used method to measure H4 ligand signaling and binding to generate estimates of functional potency and receptor affinity, respectively.

[0007] The discovery of H4R antagonists using these technologies and their investigation in multiple animal disease models including asthma, chronic pruritus, dermatitis, rheumatoid arthritis, gastric ulcerogenesis and colitis have demonstrated that H4R antagonism results in profound anti-inflammatory effects and have validated the therapeutic benefit of targeting this receptor. The first Phase 2a clinical trial of an H4R antagonist has been conducted in patients with moderate to severe atopic dermatitis, further validating H4 as a druggable target in patients.

[0008] Despite the many published H4R ligands, there is still a need to develop new H4R antagonists with good candidate drug quality. These antagonists should show excellent low nM potency and affinity, with sufficient selectivity for H1 receptors-H3 receptors. They should not show agonist activity due to the risks associated with the induction of proinflammatory responses, and ideally, they should show similar pharmacological profiles across species to support PK / PD in multiple disease animal models. They should be metabolically stable, have excellent PK, be non-toxic, and show excellent H4 specificity in extensive safety panel profiling.

[0009] The human ether-a-go-go related gene (hERG) encodes a pore-forming subunit of the rapidly activating delayed rectifier potassium channel (IKr) that plays an important role in ventricular repolarization and in determining the QT interval of the electrocardiogram, which is the time it takes for the ventricles to depolarize and repolarize. It is widely acknowledged that hERG is highly susceptible to inhibition by a wide range of structurally diverse compounds. When the channel's ability to conduct electrical current across a cell membrane is inhibited or impaired by the application of a drug, a potentially fatal disorder known as QT syndrome may result. Many clinically successful drugs on the market have a propensity to inhibit hERG and, as a side effect, produce an attendant risk of sudden death, making hERG inhibition an important anti-target that must be avoided during drug development.

[0010] The compounds of the present invention are antagonists of the H4 receptor. Certain compounds have low hERG inhibition, making these compounds particularly beneficial.

[0011] invention

[0012] The present invention provides compounds having activity as H4 receptor antagonists. More particularly, the present invention provides compounds combining H4 receptor antagonism with low hERG activity.

[0013] Therefore, the present invention provides a compound of formula (1):

[0014]

[0015] or a salt thereof, wherein;

[0016] X is CH or N;

[0017] n is 1 or 2;

[0018] R 1 Select from H or C 1-3 alkyl;

[0019] R 2 is H; and

[0020] A represents an optionally substituted pyrazole ring;

[0021] Wherein the compound is selected from the group consisting of:

[0022]

[0023]

[0024]

[0025] or a salt thereof.

[0026] The compound can be used as an H4 receptor antagonist. The compound can be used to manufacture a drug. The compound or drug can be used to treat, prevent, improve, control or reduce the risk of inflammatory disorders, including asthma, chronic pruritus, dermatitis, rheumatoid arthritis, gastric ulceration and colitis. DETAILED DESCRIPTION OF THE INVENTION

[0028] The present invention relates to novel compounds. The present invention also relates to the use of novel compounds as antagonists of H4 receptors. The present invention also relates to the use of novel compounds in the manufacture of drugs used as H4 receptor antagonists, or for the treatment of H4 system dysfunction. The present invention also relates to compounds, compositions and drugs that are selective H4 receptor antagonists.

[0029] The invention also relates to compounds, compositions and medicaments useful for treating acute and chronic inflammation, autoimmune diseases, host defense disorders and neuropathic pain. The invention also relates to compounds, compositions and medicaments useful for treating inflammatory disorders including asthma, chronic pruritus, dermatitis, rheumatoid arthritis, gastric ulcerogenesis and colitis.

[0030] The compounds of the present invention include compounds of formula (1):

[0031]

[0032] or a salt thereof, wherein;

[0033] X is CH or N;

[0034] n is 1 or 2;

[0035] R 1 Select from H or C 1-3 alkyl;

[0036] R 2 is H; and

[0037] A represents an optionally substituted pyrazole ring;

[0038] Wherein the compound is selected from the group consisting of:

[0039]

[0040]

[0041]

[0042] or a salt thereof.

[0043] The compounds of the present invention include compounds of formula (1a):

[0044]

[0045] or a salt thereof, wherein;

[0046] n is 1 or 2;

[0047] R 1 Select from H or C 1-3 alkyl;

[0048] R 2 is H; and

[0049] A represents an optionally substituted pyrazole ring;

[0050] Wherein the compound is selected from the group consisting of:

[0051]

[0052]

[0053]

[0054] or a salt thereof.

[0055] The compound may be selected from the group consisting of:

[0056] 4-(1-(difluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0057] 4-(3-(methylamino)azetidin-1-yl)-6-(1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)pyrimidin-2-amine;

[0058] 4-(1-ethyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0059] 4-(1-(difluoromethyl)-3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0060] (R)-4-(5-chloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)pyrrolidin-1-yl)pyrimidin-2-amine;

[0061] 4-(3-aminoazetidin-1-yl)-6-(1-(trifluoromethyl)-1H-pyrazol-4-yl)pyrimidin-2-amine;

[0062] 4-(3-(ethylamino)azetidin-1-yl)-6-(1-(trifluoromethyl)-1H-pyrazol-4-yl)pyrimidin-2-amine;

[0063] 4-(1,4-dimethyl-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0064] 4-(1-(2,2-difluoroethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0065] 4-(1-(2-fluoroethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0066] 4-(1-isopropyl-3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0067] 4-(5-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0068] 4-(1-ethyl-3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0069] (R)-4-(1-ethyl-3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)pyrrolidin-1-yl)pyrimidin-2-amine;

[0070] 4-(5-chloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0071] 4-(1-(difluoromethyl)-5-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0072] 4-(4-methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0073] 4-(1,3-dimethyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0074] 4-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0075] 4-(3-methyl-1-(trifluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0076] 4-(1-ethyl-5-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0077] 4-(1-isopropyl-5-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0078] 4-(5-methyl-1-(trifluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0079] 4-(1,3-dimethyl-1H-pyrazol-5-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0080] 4-(3-ethyl-1-methyl-1H-pyrazol-5-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0081] 4-(3-chloro-1-methyl-1H-pyrazol-5-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0082] 4-(1-methyl-3-(trifluoromethyl)-1H-pyrazol-5-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0083] 4-(3,5-dichloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0084] 4-(3-chloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0085] 4-(5-bromo-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0086] 4-(3-bromo-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0087] 4-(3-(methylamino)azetidin-1-yl)-6-(1-(trifluoromethyl)-1H-pyrazol-4-yl)pyridin-2-amine;

[0088] (R)-4-(3-(methylamino)pyrrolidin-1-yl)-6-(1-(trifluoromethyl)-1H-pyrazol-4-yl)pyridin-2-amine;

[0089] (R)-4-(3-chloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)pyrrolidin-1-yl)pyrimidin-2-amine;

[0090] 4-(5-methyl-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0091] 4-(3-(Methylamino)azetidin-1-yl)-6-(1H-pyrazol-3-yl)pyrimidin-2-amine;

[0092] 4-(3-(methylamino)azetidin-1-yl)-6-(3-(trifluoromethyl)-1H-pyrazol-4-yl)pyrimidin-2-amine;

[0093] 4-(3-(Methylamino)azetidin-1-yl)-6-(1H-pyrazol-4-yl)pyrimidin-2-amine;

[0094] 4-(3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0095] 4-(5-ethyl-4-methyl-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0096] 4-(5-ethyl-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0097] 4-(4,5-dichloro-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine;

[0098] or a salt thereof.

[0099] The compound may be a compound selected from the group consisting of:

[0100]

[0101]

[0102] or a salt thereof.

[0103] The compound may be a compound selected from the group consisting of:

[0104]

[0105] or a salt thereof.

[0106] Specific examples of compounds include those with low hERG activity. The compounds of the present invention exhibit low hERG activity, which is particularly beneficial for the reasons outlined in the background section above. Compounds exhibiting low hERG activity herein are particularly those having a hERG pIC of 4.5 or less. 50 of compounds.

[0107] definition

[0108] In this application, the following definitions apply unless indicated otherwise.

[0109] With respect to the use of any compound described herein, the term "treatment" is used to describe any form of intervention in which a compound is administered to a subject suffering from, or at risk of, or potentially at risk of the disease or disorder in question. Thus, the term "treatment" encompasses both preventative (prophylactic) treatment and treatment in which measurable or detectable symptoms of a disease or disorder are exhibited.

[0110] As used herein, the term "therapeutically effective amount" (e.g., with respect to a method of treatment of a disease or condition) refers to an amount of a compound effective to produce the desired therapeutic effect. For example, if the condition is pain, a therapeutically effective amount is an amount sufficient to provide a desired level of pain relief. A desired level of pain relief can be, for example, complete removal of pain or a reduction in the severity of pain.

[0111] To the extent that any of the compounds described have chiral centers, the present invention extends to all optical isomers of such compounds, whether in the form of racemates or resolved enantiomers. However, the invention described herein relates to all crystalline forms, solvates and hydrates of any disclosed compound so prepared. To the extent that any of the compounds disclosed herein have acidic centers or basic centers such as carboxylic acid groups or amino groups, all salt forms of the compounds are included herein. In the case of pharmaceutical use, salts should be considered as pharmaceutically acceptable salts.

[0112] Salts or pharmaceutically acceptable salts that may be mentioned include acid addition salts and base addition salts. Such salts can be formed by conventional means, for example, by reacting the free acid form or free base form of the compound with one or more equivalents of a suitable acid or base, optionally in a solvent or in a medium in which the salt is insoluble, followed by removal of the solvent or medium using standard techniques (e.g., in a vacuum, by freeze drying or by filtering). Salts can also be prepared, for example, using suitable ion exchange resins, by exchanging the counter ions of the compound in salt form with another counter ion.

[0113] Examples of pharmaceutically acceptable salts include acid addition salts derived from inorganic and organic acids, and salts derived from metals such as sodium, magnesium, potassium and calcium.

[0114] Examples of acid addition salts include acid addition salts formed with acetic acid, 2,2-dichloroacetic acid, adipic acid, alginic acid, arylsulfonic acids (e.g., benzenesulfonic acid, naphthalene-2-sulfonic acid, naphthalene-1,5-disulfonic acid, and p-toluenesulfonic acid), ascorbic acid (e.g., L-ascorbic acid), L-aspartic acid, benzoic acid, 4-acetamidobenzoic acid, butyric acid, (+) camphoric acid, camphorsulfonic acid, (+)-(1S)-camphor-10-sulfonic acid, decanoic acid, hexanoic acid, caprylic acid, cinnamic acid, citric acid, cyclamic acid, dodecylsulfuric acid, ethane-1,2-disulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, formic acid, fumaric acid, galactaric acid, gentisic acid, glucoheptanoic acid, gluconic acid (e.g., D-gluconic acid), glucuronic acid (e.g.,

[0013] Examples of the present invention include, but are not limited to, D-glucuronic acid), glutamic acid (e.g., L-glutamic acid), α-oxoglutaric acid, glycolic acid, hippuric acid, hydrobromic acid, hydrochloric acid, hydroiodic acid, isethionic acid, lactic acid (e.g., (+)-L-lactic acid and (±)-DL-lactic acid), lactobionic acid, maleic acid, malic acid (e.g., (-)-L-malic acid), malonic acid, (±)-DL-mandelic acid, metaphosphoric acid, methanesulfonic acid, 1-hydroxy-2-naphthoic acid, nicotinic acid, nitric acid, oleic acid, orotic acid, oxalic acid, palmitic acid, pamoic acid, phosphoric acid, propionic acid, L-pyroglutamic acid, salicylic acid, 4-aminosalicylic acid, sebacic acid, stearic acid, succinic acid, sulfuric acid, tannic acid, tartaric acid (e.g., (+)-L-tartaric acid), thiocyanic acid, undecylenic acid, and valeric acid.

[0115] Also contemplated are any solvates of the compounds and their salts. Preferred solvates are solvates formed by incorporating molecules of a non-toxic pharmaceutically acceptable solvent (hereinafter referred to as a solvating solvent) into the solid state structure (e.g., crystal structure) of the compounds of the present invention. Examples of such solvents include water, alcohols (such as ethanol, isopropanol and butanol) and dimethyl sulfoxide. Solvates can be prepared by recrystallizing the compounds of the present invention with a solvent or a solvent mixture containing a solvating solvent. Whether a solvate has been formed in any given case can be determined by subjecting the crystals of the compound to analysis using well-known and standard techniques such as thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray crystallography.

[0116] Solvates can be stoichiometric or non-stoichiometric solvates. Specific solvates can be hydrates, and examples of hydrates include hemihydrates, monohydrates, and dihydrates. For a more detailed discussion of solvates and methods for preparing and characterizing them, see Bryn et al., Solid-State Chemistry of Drugs, Second Edition, published by SSCI, Inc of West Lafayette, IN, USA, 1999, ISBN 0-967-06710-3.

[0117] In the context of the present invention, the term "pharmaceutical composition" means a composition comprising an active agent and additionally comprising one or more pharmaceutically acceptable carriers. Depending on the nature of the mode of administration and the dosage form, the composition may also comprise ingredients selected from, for example, diluents, adjuvants, excipients, vehicles, preservatives, fillers, disintegrants, wetting agents, emulsifiers, suspending agents, sweeteners, flavoring agents, perfuming agents, antibacterial agents, antifungal agents, lubricants and dispersants. The composition may take, for example, the form of tablets, dragees, powders, elixirs, syrups, liquid products including suspensions, sprays, inhalants, tablets, lozenges, emulsions, solutions, cachets, granules, capsules and suppositories, as well as liquid products for injection, including liposomal products.

[0118] The compounds of the present invention may contain one or more isotopic substitutions, and reference to a particular element includes within its scope all isotopes of that element. For example, reference to hydrogen would include 1 H. 2 H(D) and 3 H(T) is included within its scope. Similarly, references to carbon and oxygen will be 12 C. 13 C and 14 C and 16 O and 18 O is included in their scope.In a similar manner, unless the context indicates otherwise, mentioning a particular functional group also includes isotopic modification in its scope.For example, mentioning an alkyl group such as an ethyl group or an alkoxy group such as a methoxy group also includes a modification in which one or more hydrogen atoms in the group are in the form of deuterium or tritium isotopes, for example, such as an ethyl group (perdeuteroethyl group) in which all five hydrogen atoms are in the form of deuterium isotopes, or a methoxy group (trideuteromethoxy group) in which all three hydrogen atoms are in the form of deuterium isotopes.Isotopes can be radioactive or non-radioactive.

[0119] The therapeutic dose may vary depending on the patient's needs, the severity of the condition being treated, and the compound being employed. The determination of a dose suitable for a particular situation is within the skill of the art. Typically, treatment is initiated with a smaller dose that is less than the optimal dose of the compound. Thereafter, the dose is increased in small increments until the optimal effect in the situation is achieved. For convenience, the total daily dose may be divided and administered in batches during a day if desired.

[0120] Of course, the size (magnitude) of the effective dose of the compound will vary with the nature of the severity of the condition to be treated and with the specific compound and its route of administration. The selection of suitable dosage is within the ability of those of ordinary skill in the art, without excessive burden. Usually, the daily dosage range can be from about 10 μg to about 30 mg per kg of human body weight and non-human animal body weight, preferably from about 50 μg to about 30 mg per kg of human body weight and non-human animal body weight, for example, from about 50 μg to about 10 mg per kg of human body weight and non-human animal body weight, for example, from about 100 μg to about 30 mg per kg of human body weight and non-human animal body weight, for example, from about 100 μg to about 10 mg per kg of human body weight and non-human animal body weight, and most preferably from about 100 μg to about 1 mg per kg of human body weight and non-human animal body weight.

[0121] Process for preparing the compounds of the present invention

[0122] There is provided a process for preparing a compound as defined above, comprising:

[0123] (A) Compounds of formula (10):

[0124]

[0125] With the compound of formula (11):

[0126]

[0127] reacting under SNAr conditions or under transition metal catalyzed coupling conditions; wherein A is an optionally substituted pyrazole ring; R 1 is H, methyl or ethyl; R 2 is H; X is N or CH; n is 1 or 2; and LG represents a suitable leaving group; or

[0128] (B) Compounds of formula (12):

[0129]

[0130] With the compound of formula (13):

[0131] AM (13)

[0133] The reaction is carried out under transition metal catalytic coupling conditions or under SNAr conditions; wherein A, R 1 , R 2 , X and n are as defined above, LG represents a suitable leaving group, and M (which may be present or absent) represents a suitably substituted metal or non-metal; or

[0134] In process variant (A), a compound of formula (10) can be reacted with a compound of formula (11) under SNAr conditions. The SNAr reaction is generally carried out as follows: using an excess of a compound of formula (11) or a stoichiometric amount of a compound of formula (11), in the presence of a base, which can be a tertiary amine base such as TEA or DIPEA or an inorganic base such as K2CO3, Cs2CO3 or NaHCO3, optionally in a suitable solvent such as H2O, MeCN, 1,4-dioxane, THF, MeOH, EtOH, IPA, BuOH, DMF, NMP or DMSO or in a combination of suitable solvents, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure, optionally in the presence of an additive such as KF or a silver salt. Optionally, the compound of formula (11) may be present in the reaction as an acid salt such as HCl salt, HBr salt or TFA salt, optionally in the presence of a tertiary amine base such as TEA or DIPEA. The leaving group LG in the compound of formula (10) may be a halogen such as F, Cl or Br; an alkoxy group such as OMe; an aryloxy group such as pentafluorophenoxy; a sulfenyl group such as SMe; a sulfinyl group such as SOMe; a sulfonyl group such as SO2Me, a sulfonyloxy group such as OTs, OMs, ONs or OTf; or a leaving group generated by the reaction of a hydroxyl group with a peptide coupling reagent such as BOP, PyBOP or HATU.

[0135] Alternatively, in process variant (A), the compound of formula (10) can be reacted with the compound of formula (11) under transition metal catalyzed coupling conditions. The transition metal catalyzed coupling reaction is generally carried out as follows: using the compound of formula (11) in the presence of an inorganic base such as NaO t Bu, KO t In the presence of Bu, K3PO4, K2CO3 or Cs2CO3, in a suitable solvent such as 1,4-dioxane, THF, DME or toluene or in a combination of suitable solvents, in the presence of a substoichiometric amount of a transition metal catalyst such as Pd(OAc)2, Pd2(dba)3, Pd(dppf)Cl2, Pd(PPh3)2Cl2 or Pd(PPh3)4, optionally in the presence of a substoichiometric amount of a phosphine ligand such as PPh3, PBu3, P tIn the presence of Bu3, XPhos, Xantphos or BINAP, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (10) can be a halogen such as Cl, Br or I, or a sulfonyloxy group such as OTs, OMs, ONs or OTf.

[0136] Compounds of formula (10) can be prepared by the reaction shown in Scheme 1 below:

[0137]

[0138] Thus, where X is as defined above and LG and LG 1 Compounds of formula (14) which may be the same or different and represent a suitable leaving group may be reacted with compounds of formula (13) in which A is as defined above and M (which may be present or absent) represents a suitably substituted metal or non-metal under transition metal catalytic coupling conditions or under SNAr conditions to form compounds of formula (10). Transition metal catalytic coupling reactions or SNAr reactions are generally carried out as described below in process variant (B), and compounds of formula (13) and formula (14) may be commercially available or may be easily prepared by simple starting materials known to technicians by standard methods reported in the open literature. Sometimes, due to their instability, it may be necessary to generate compounds of formula (13) in which M is present in situ at low temperatures, for example between -78°C and room temperature, and further react them in transition metal catalytic coupling reactions without separating them in advance. The details of such methods are known in the open literature, for example as reported by Oberli and Buchwald in Org. Lett., 2012, Vol. 14, No. 17, p. 4606.

[0139] Alternatively, compounds of formula (10) wherein X represents N and LG represents Cl can generally be prepared by the reaction sequence shown in Scheme 2 below:

[0140]

[0141] Thus, a carboxylic acid of formula (15) can be identified as the corresponding β-ketoester (16) by first activating it via a number of standard methods known to the skilled artisan, for example by reaction with CDI in a suitable solvent such as MeCN, and then with a malonic acid derivative such as potassium 3-ethoxy-3-oxopropanoate in the presence of a Lewis acid such as MgCl. Once formed, the β-ketoester (16) can be precipitated by reaction with a suitable base such as KOH. tThe amino-hydroxypyrimidine analog (17) is cyclized to the amino-hydroxypyrimidine analog (17) by reaction with guanidine or an appropriate guanidine salt in a suitable solvent such as MeOH in the absence of Bu. The amino-hydroxypyrimidine analog (17) thus formed can then be reacted with POCl3 in the presence or absence of a suitable solvent to form a compound of formula (18). The compound of formula (15) can be commercially available or can be readily prepared from simple starting materials known to the skilled person by standard methods reported in the open literature.

[0142] Compounds of formula (11) are either commercially available or can be readily prepared by standard methods reported in the open literature from simple starting materials known to the skilled person.

[0143] In process variant (B), compounds of formula (12) can be reacted with compounds of formula (13) under transition metal catalyzed coupling conditions. Transition metal catalyzed coupling reactions are typically carried out using compounds of formula (13) wherein M is present. For example, when M represents a boronic acid -B(OH)2, or a boronic ester such as -B(OMe)2, -B(OiPr)2 or Bpin, or a lithium trialkylborate such as -B(OiPr)3Li, then the transition metal catalyzed coupling reaction is typically carried out as follows: in the presence of an inorganic base such as NaHCO3, Na2CO3, K2CO3, Cs2CO3 or K3PO4, in a suitable solvent such as H2O, MeCN, 1,4-dioxane, THF, Et2O, DME, EtOH, IPA, DMF, NMP or toluene or in a combination of suitable solvents, in the presence of a substoichiometric amount of a transition metal catalyst such as Pd(OAc)2, Pd2(dba)3, Pd(dppf)Cl2, Pd(PPh3)2Cl2, Pd(PPh3)4 or a transition metal precatalyst such as XPhos Pd G2, optionally in the presence of a substoichiometric amount of a phosphine ligand such as PPh3, P t In the presence of Bu3, PCy3 or XPhos, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) can be a halogen such as Cl, Br or I, or a sulfonyloxy group such as OTs, OMs or OTf.

[0144] Alternatively, when M represents trifluoroborate BF3 -When, the transition metal catalyzed coupling reaction is generally carried out as follows: in the presence of an inorganic base such as Na2CO3, K2CO3, Cs2CO3 or K3PO4, in a suitable solvent such as H2O, MeCN, 1,4-dioxane, THF, MeOH or EtOH or in a combination of suitable solvents, in the presence of a substoichiometric amount of a transition metal catalyst such as Pd(OAc)2, Pd2(dba)3, optionally in the presence of a substoichiometric amount of a phosphine ligand such as PPh3, PCy3 or RuPhos, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) may be a halogen such as Cl, Br or I.

[0145] Alternatively, when M represents a trialkyltin group such as SnMe3 or SnBu3, the transition metal catalyzed coupling reaction is generally carried out as follows: in a suitable solvent such as 1,4-dioxane, THF, DMF or toluene or in a combination of suitable solvents, in the presence of a substoichiometric amount of a transition metal catalyst such as Pd(OAc)2, Pd2(dba)3, Pd(PPh3)2Cl2 or Pd(PPh3)4, optionally in the presence of an inorganic base such as K2CO3 or CsF, optionally in the presence of an additive such as LiCl, CuI, Bu4NBr or Et4NCl, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) can be a halogen such as Cl, Br or I.

[0146] Alternatively, when M is absent, the transition metal catalyzed coupling reaction is generally carried out as follows: in the presence of an inorganic base such as NaO t Bu, KO t In the presence of Bu, K3PO4, K2CO3 or Cs2CO3, in a suitable solvent such as 1,4-dioxane, THF, DME or toluene or in a combination of suitable solvents, in the presence of a substoichiometric amount of a transition metal catalyst such as Pd(OAc)2, Pd2(dba)3, Pd(dppf)Cl2, Pd(PPh3)2Cl2 or Pd(PPh3)4, optionally in the presence of a substoichiometric amount of a phosphine ligand such as PPh3, PBu3, P tIn the presence of Bu3, XPhos, Xantphos or BINAP, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) can be a halogen such as Cl, Br or I, or a sulfonyloxy group such as OTs, OMs, ONs or OTf.

[0147] Alternatively, when M is absent, the transition metal catalyzed coupling reaction is generally carried out as follows: in the presence of an inorganic base such as K3PO4, K2CO3 or Cs2CO3, in a suitable solvent such as 1,4-dioxane, DMF, DMSO or toluene or in a combination of suitable solvents, in the presence of a substoichiometric amount of a transition metal catalyst such as CuI, optionally in the presence of a substoichiometric amount of an amine such as (S)-proline or trans-N 1 ,N 2 -dimethylcyclohexane-1,2-diamine, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) can be a halogen such as Cl, Br or I.

[0148] Alternatively, when M is absent, the transition metal catalyzed coupling reaction is generally carried out as follows: in the presence of an organic base such as n In the presence of Bu4OAc, in a suitable solvent such as 1,4-dioxane, in the presence of a substoichiometric amount of a transition metal precatalyst such as XPhos Pd G2, optionally in the presence of a substoichiometric amount of a phosphine ligand such as XPhos, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) may be a halogen such as Cl.

[0149] Alternatively, in process variant (B), the compound of formula (12) can be reacted with the compound of formula (13) under SNAr conditions. The SNAr reaction is generally carried out as follows: using a compound of formula (13) in which M is absent, in the presence of a tertiary amine base such as TEA or DIPEA or an inorganic base such as K2CO3, Cs2CO3, KO tIn the presence of Bu or NaH, in a suitable solvent such as THF, DMF, H2O, DMSO or NMP or in a combination of suitable solvents, at a temperature between about room temperature and about 200°C, using conventional heating or optionally heating by microwave irradiation, in an open container or optionally in a sealed container, optionally at a pressure greater than atmospheric pressure. The leaving group LG in the compound of formula (12) can be a halogen such as F, Cl or Br; an alkoxy group such as OMe; an aryloxy group such as pentafluorophenoxy; a thioalkyl group such as SMe; a sulfinyl group such as SOMe; a sulfonyl group such as SO2Me, or a sulfonyloxy group such as OTs, OMs, ONs or OTf.

[0150] Compounds of formula (12) can be prepared by the reaction sequence shown in Scheme 3 below:

[0151]

[0152] Thus, where X is as defined above and LG and LG 1 Compounds of formula (14) which may be the same or different and represent a suitable leaving group may be reacted under SNAr conditions or under transition metal catalyzed coupling conditions with a compound wherein R 1 , R 2 and n is defined above to form a compound of formula (12). The SNAr reaction or transition metal catalyzed coupling reaction is generally carried out as described above in process variant (A).

[0153] In many reactions described above, it may be necessary to protect one or more groups to prevent the reaction from occurring at undesirable positions on the molecule. Examples of protecting groups, as well as methods for protecting and deprotecting functional groups, can be found in Greene's Protective Groups in Organic Synthesis, Fifth Edition, Editor: Peter GMWuts, John Wiley, 2014, (ISBN: 9781118057483). In particular, useful protecting groups for operating compounds of formula (10) or (12) include 2,5-dimethyl-1H-pyrrole groups; useful protecting groups for operating compounds of formula (11) or (12) include BOC and CBZ; and useful protecting groups for operating compounds of formula (13) include SEM and THP.

[0154] The compounds prepared by the aforementioned methods can be isolated and purified by any of a variety of methods well known to those skilled in the art, and examples of such methods include recrystallization and chromatographic techniques such as column chromatography (eg flash chromatography), HPLC and SFC.

[0155] Pharmaceutical preparations

[0156] While it is possible for the active compound to be administered alone, it is preferable to present it as a pharmaceutical composition (eg, formulation).

[0157] The present invention therefore provides a pharmaceutical composition comprising at least one compound of the invention as defined above together with at least one pharmaceutically acceptable excipient.

[0158] The composition may be a tablet composition.

[0159] The composition may be a capsule composition.

[0160] Pharmaceutically acceptable excipients can be selected from, for example, carriers (e.g., solid, liquid or semisolid carriers), excipients, diluents (e.g., solid diluents such as fillers or bulking agents; and liquid diluents such as solvents and co-solvents), granulating agents, binders, flow aids, coating agents, release controlling agents (e.g., release-delaying or release-retarding polymers or waxes), binding agents, disintegrants, buffers, lubricants, preservatives, antifungal and antibacterial agents, antioxidants, buffers, tonicity regulators, thickeners, flavoring agents, sweeteners, pigments, plasticizers, taste-masking agents, stabilizers or any other excipients conventionally used in pharmaceutical compositions.

[0161] The term "pharmaceutically acceptable" as used herein means compounds, materials, compositions and / or dosage forms that are, within the scope of sound medical judgment, suitable for use in contact with the tissues of subjects (e.g., human subjects) without excessive toxicity, irritation, allergic response, or other problems or complications, commensurate with a reasonable benefit / risk ratio. Each excipient must also be "acceptable" in the sense of being compatible with the other ingredients of the formulation.

[0162] Pharmaceutical compositions containing compounds of the invention may be formulated according to known techniques, see, for example, Remington's Pharmaceutical Sciences, Mack Publishing Company, Easton, PA, USA.

[0163] The pharmaceutical composition may be in any form suitable for oral, parenteral, topical, intranasal, intrabronchial, sublingual, ocular, otic, rectal, intravaginal or transdermal administration.

[0164] Suitable pharmaceutical dosage forms for oral administration include tablets (coated or uncoated), capsules (hard shell or soft shell), caplets, pills, lozenges, syrups, solutions, powders, granules, elixirs and suspensions, sublingual tablets, wafers or patches such as buccal patches.

[0165] Tablet compositions may contain a unit dose of active compound together with an inert diluent or carrier, such as a sugar or sugar alcohol, e.g., lactose, sucrose, sorbitol, or mannitol; and / or a non-sugar-derived diluent, such as sodium carbonate, calcium phosphate, calcium carbonate, or cellulose or a derivative thereof, such as microcrystalline cellulose (MCC), methylcellulose, ethylcellulose, hydroxypropylmethylcellulose, and starch such as corn starch. Tablets may also contain standard ingredients such as: a binder and a granulating agent, such as polyvinylpyrrolidone; a disintegrant (e.g., a swellable cross-linked polymer, such as cross-linked carboxymethylcellulose); a lubricant (e.g., stearate); a preservative (e.g., paraben); an antioxidant (e.g., BHT); a buffer (e.g., a phosphate buffer or a citrate buffer); and an effervescent agent, such as a citrate / bicarbonate mixture. Such excipients are well known and need not be discussed in detail herein.

[0166] Tablets can be designed to release the drug upon contact with gastric fluid (immediate release tablets), or to release in a controlled manner over an extended period of time or in a specific area of ​​the GI tract (controlled release tablets).

[0167] The pharmaceutical composition generally comprises from about 1% (w / w) to about 95% (w / w) of active ingredient and from 99% (w / w) to 5% (w / w) of pharmaceutically acceptable excipients (e.g., as defined above) or a combination of such excipients. Preferably, the composition comprises from about 20% (w / w) to about 90% (w / w) of active ingredient and from 80% (w / w) to 10% (w / w) of pharmaceutically acceptable excipients or a combination of excipients. The pharmaceutical composition comprises from about 1% (w / w) to about 95% (w / w), preferably from about 20% (w / w) to about 90% (w / w) of active ingredient. The pharmaceutical composition according to the present invention can be, for example, in unit dose form, such as in the form of ampoules, vials, suppositories, prefilled syringes, dragees, powders, tablets or capsules.

[0168] Tablets and capsules may contain, for example, 0%-20% (w / w) of disintegrants, 0%-5% (w / w) of lubricants, 0%-5% (w / w) of glidants, and / or 0%-99% (w / w) of fillers or bulking agents (depending on the drug dose). They may also contain 0%-10% (w / w) of polymer binders, 0%-5% (w / w) of antioxidants, 0%-5% (w / w) of pigments. In addition, slow-release tablets will typically also contain 0%-99% (w / w) of controlled-release (e.g., delayed-release) polymers (depending on the dose). The film coating of a tablet or capsule typically contains 0%-10% (w / w) of a polymer, 0%-3% (w / w) of a pigment, and / or 0%-2% (w / w) of a plasticizer.

[0169] Parenteral formulations typically contain 0%-20% (w / w) buffer, 0%-50% (w / w) cosolvent and / or 0%-99% (w / w) water for injection (WFI) (depending on dose and whether lyophilized). Formulations for intramuscular depots may also contain 0%-99% (w / w) oil.

[0170] Pharmaceutical formulations may be provided to patients in "patient packs" containing an entire course of treatment within a single package, usually a blister pack.

[0171] The compounds of the present invention will generally be presented in unit dosage form, and therefore will generally contain enough compound to provide the desired level of biological activity. For example, the formulation may contain from 1 nanogram to 2 grams of active ingredient, for example from 1 nanogram to 2 milligrams of active ingredient. Within these ranges, a specific subrange of the compound is 0.1 milligram to 2 grams of active ingredient (more typically from 10 milligrams to 1 gram, for example 50 milligrams to 500 milligrams), or 1 microgram to 20 milligrams (e.g. 1 microgram to 10 milligrams, for example 0.1 milligram to 2 milligrams of active ingredient).

[0172] For oral compositions, unit dosage forms may contain from 1 mg to 2 g, more usually 10 mg to 1 g, for example 50 mg to 1 g, for example 100 mg to 1 g, of active compound.

[0173] The active compound will be administered to a patient (eg, a human patient or an animal patient) in need thereof in an amount sufficient to achieve the desired therapeutic effect (effective amount). The precise amount of compound administered can be determined by the supervising physician according to standard procedures. Example

[0174] The invention will now be illustrated, without however being limited, by reference to the following examples.

[0175] Example 1 to Example 42

[0176] The compounds of Example 1 to Example 42 shown below in Table 1 have been prepared. The NMR and LCMS properties of the compounds and the methods used to prepare them are set forth in Table 3. The starting materials used for each of the examples are listed in Table 2. For Example 20, Example 23, Example 32 and Example 33, a suggested synthetic route is shown.

[0177] Table 1 - Exemplary compounds

[0178]

[0179]

[0180]

[0181] General Procedure

[0182] Where preparative routes are not included, the relevant intermediates are commercially available. Commercial reagents were used without further purification. Room temperature (rt) refers to about 20°C-27°C. The data were recorded at 400 MHz on a Bruker or Jeol instrument. 1 HNMR spectra. Chemical shift values ​​are expressed in parts per million (ppm), i.e. (δ) values. The following abbreviations are used for the multiplicity of NMR signals: s = singlet, br = broad, d = doublet, t = triplet, q = quartet, quint = quintet, td = triplet of doublet, tt = triplet of triplet, qd = quartet of doublet, ddd = doublet of doublet of doublet, ddt = doublet of doublet of triplet, m = multiplet. Coupling constants are listed as J values ​​measured in Hz. NMR and mass spectrometry results have been corrected to account for background peaks. Chromatography refers to column chromatography performed using 60-120 mesh silica gel and carried out under nitrogen pressure (flash chromatography). Column chromatography using 'basic silica' refers to column chromatography using KP-NH silica gel. Column chromatography using 'C18 silica' under reverse phase conditions refers to the use of KP-C18 silica gel. TLC used to monitor the reactions refers to TLC run with the specified mobile phase and silica gel F254 from Merck as stationary phase. Microwave mediated reactions were performed in a Biotage Initiator or CEM Discover microwave reactor.

[0183] LCMS analysis

[0184] LCMS analysis of the compounds was performed under electrospray conditions using the instrumentation and methods given in the table below:

[0185] system Instrument Name LC Detector Quality detector 1 Shimadzu Nexera Photodiode array LCMS-2020 2 Agilent 1290RRLC Photodiode array Agilent 6120

[0186]

[0187] The LCMS data in the Experimental section and Tables 2 and 3 are given in the following format: (Instrument system, Method): mass ion, retention time, UV detection wavelength.

[0188] Compound purification

[0189] Final purification of compounds was performed by preparative reverse phase HPLC using the instrumentation and methods detailed below, with data given in the following format: Purification Technique: [Phase (column description, column length x internal diameter, particle size), Solvent flow, Gradient - given as % of mobile phase B in mobile phase A (over time), Mobile Phase (A), Mobile Phase (B)].

[0190] Preparative HPLC purification:

[0191] Shimadzu LC-20AP Binary System with SPD-20A UV Detector

[0192] Gilson semi-preparative HPLC system with 321 pump, GX-271 liquid handler and Gilson 171 DAD controlled by Gilson Trilution software

[0193] Purification Method A

[0194] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 12 mL / min, gradient 0%-30% (over 17 min), 100% (over 1 min), 100%-0% (over 4 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0195] Purification method B

[0196] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 12 mL / min, gradient 0%-15% (over 24 min), 15%-15% (over 3 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0197] Purification Method C

[0198] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 16 mL / min, gradient 5%-15% (over 18 min), 15%-15% (over 2 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0199] Purification method D

[0200] Preparative HPLC: [reverse phase (X-select CSH Phenyl Hexyl C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 3%-3% (over 40 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0201] Purification Method E

[0202] Preparative HPLC: [reverse phase (Gemini-NX C-18, 150×21.2 mm, 5 μm), 16 mL / min, gradient 5%-30% (over 25 min), 100% (over 3 min), 100%-5% (over 4 min), mobile phase (A): 5 mM ammonium bicarbonate + 0.1% ammonia in water, (B): 100% acetonitrile].

[0203] Purification Method F

[0204] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 13 mL / min, gradient 5%-20% (over 22 min), 20%-20% (over 3 min), 100% (over 2 min), 100%-5% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0205] Purification Method G

[0206] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 13 mL / min, gradient 0%-15% (over 24 min), 15%-15% (over 5 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0207] Purification Method H

[0208] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-30% (over 17 min), 100% (over 1 min), 100%-0% (over 4 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0209] Purification Law I

[0210] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 15 mL / min, gradient 0%-15% (over 25 min), 15%-15% (over 4 min), 100% (over 2 min), 100%-5% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0211] Purification method J

[0212] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 15 mL / min, gradient 5%-12% (over 28 min), 100% (over 2 min), 100%-5% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0213] Purification Method K

[0214] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 15 mL / min, gradient 0%-15% (over 18 min), 15%-15% (over 5 min), 100% (over 2 min), 100%-0% (over 3 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0215] Purification method L

[0216] Preparative HPLC: [reverse phase (X-select CSH Phenyl Hexyl C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-20% (over 23 min), 100% (over 2 min), 100%-0% (over 3 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0217] Purification Law

[0218] Preparative HPLC: [reverse phase (Sunfire C-18, 250×18 mm, 5 μm), 14 mL / min, gradient 0%-20% (over 22 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0219] Purification Method N

[0220] Preparative HPLC: [reverse phase (Sunfire C-18, 250×18 mm, 5 μm), 15 mL / min, gradient 0%-20% (over 22 min), 100% (over 2 min), 100%-0% (over 2 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0221] Purification Method O

[0222] Preparative HPLC: [reverse phase (X-select CSH Phenyl Hexyl C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-5% (over 22 min), 5%-5% (over 2 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0223] Purification Method P

[0224] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 13 mL / min, gradient 10%-15% (over 24 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0225] Purification Method Q

[0226] Preparative HPLC: [reverse phase (Sunfire C-18, 250×20 mm, 5 μm), 15 mL / min, gradient 0%-30% (over 17 min), 100% (over 1 min), 100%-0% (over 4 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0227] Purification Method R

[0228] Preparative HPLC: [reverse phase (X-Bridge C-18, 250×19 mm, 5 μm), 14 mL / min, gradient 10%-30% (over 20 min), 30%-30% (over 2 min), 100% (over 2 min), 100%-10% (over 6 min), mobile phase (A): 5 mM ammonium bicarbonate + 0.1% ammonia in water, (B): 100% acetonitrile].

[0229] Purification method S

[0230] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-20% (over 20 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0231] Purification method T

[0232] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 5%-20% (over 20 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0233] Purification Method U

[0234] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 12 mL / min, gradient 0%-20% (over 25 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0235] Purification Method V

[0236] Preparative HPLC: [reverse phase (Gemini NX C-18, 150×21.2 mm, 5 μm), 15 mL / min, gradient 0%-15% (over 18 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0237] Purification Method W

[0238] Preparative HPLC: [reverse phase (Gemini NX C-18, 150×21.2 mm, 5 μm), 16 mL / min, gradient 0%-8% (over 18 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0239] Purification MethodX

[0240] Preparative HPLC: [reverse phase (X-select CSH Phenyl Hexyl C-18, 250×19 mm, 5 μm), 14 mL / min, gradient 0%-20% (over 20 min), 100% (over 3 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0241] Purification Method Y

[0242] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 14 mL / min, gradient 0%-15% (over 20 min), 15%-15% (over 2 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0243] Purification method Z

[0244] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 14 mL / min, gradient 0%-15% (over 20 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0245] Purification Method AA

[0246] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-10% (over 25 min), 10%-10% (over 2 min), 100% (over 3 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0247] Purification Method AB

[0248] Preparative HPLC: [reverse phase (X-Bridge C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 5%-27% (over 26 min), 100% (over 3 min), 100%-5% (over 5 min), mobile phase (A): 5 mM ammonium bicarbonate + 0.1% ammonia in water, (B): 100% acetonitrile].

[0249] Purification Method AC

[0250] Preparative HPLC: [reverse phase (Sunfire C-18, 250×20 mm, 5 μm), 15 mL / min, gradient 0%-30% (over 17 min), 100% (over 1 min), 100%-0% (over 4 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0251] Purification Method AD

[0252] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-10% (over 18 min), 10%-10% (over 2 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0253] Purification Method AE

[0254] Preparative HPLC: [reverse phase (Sunfire C-18, 150×19 mm, 5 μm), 15 mL / min, gradient 0%-10% (over 12 min), 100% (over 2 min), 100%-0% (over 2 min), mobile phase (A): 0.1% formic acid in water, (B): 100% acetonitrile].

[0255] Purification Method AF

[0256] Preparative HPLC: [reverse phase (X-Bridge C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-12% (over 25 min), 100% (over 2 min), 100%-0% (over 8 min), mobile phase (A): 5 mM ammonium bicarbonate + 0.1% ammonia in water, (B): 100% acetonitrile].

[0257] Purification Method AG

[0258] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-15% (over 18 min), 100% (over 3 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0259] Purification Method AH

[0260] Preparative HPLC: [reverse phase (X-Bridge C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-12% (over 20 min), 100% (over 2 min), 100%-0% (over 5 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0261] Purification Method AI

[0262] Preparative HPLC: [reverse phase (Sunfire C-18, 250×19 mm, 5 μm), 17 mL / min, gradient 0%-20% (over 17 min), 100% (over 2 min), 100%-0% (over 4 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0263] Purification Method AJ

[0264] Preparative HPLC: [reverse phase (X-Bridge C-18, 250×19 mm, 5 μm), 15 mL / min, gradient 0%-10% (over 28 min), 10%-10% (over 6 min), 100% (over 2 min), 100%-0% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0265] Purification Method AK

[0266] Preparative HPLC: [reverse phase (YMC-Actus Triart C-18, 250×20 mm, 5 μm), 16 mL / min, gradient 5%-20% (over 24 min), 100% (over 2 min), 100%-5% (over 6 min), mobile phase (A): 0.1% trifluoroacetic acid in water, (B): 100% acetonitrile].

[0267] abbreviation

[0268] CDI = Carbonyldiimidazole

[0269] DAST = Diethylaminosulfur trifluoride

[0270] DCM = dichloromethane

[0271] DIPEA=N,N-diisopropylethylamine

[0272] ESI = Electrospray Ionization

[0273] EtOAc = Ethyl acetate

[0274] h = hours

[0275] H2O = water

[0276] HCl = Hydrogen chloride, hydrochloric acid

[0277] HPLC = High Performance Liquid Chromatography

[0278] IPA = propan-2-ol

[0279] LC = Liquid Chromatography

[0280] MeCN = acetonitrile

[0281] MeOH = methanol

[0282] min(s)=minutes

[0283] MS = mass spectrometry

[0284] nm = nanometer

[0285] NMR = Nuclear Magnetic Resonance

[0286] POCl3=phosphorus oxychloride

[0287] RT = Room temperature

[0288] sat.=saturated

[0289] SFC = Supercritical Fluid Chromatography

[0290] TEA = triethylamine

[0291] TFA = trifluoroacetic acid

[0292] THF = Tetrahydrofuran

[0293] TLC = Thin Layer Chromatography

[0294] Synthesis of intermediates:

[0295] Route 1

[0296] Typical procedures for the preparation of pyrimidines, as exemplified by the preparation of Intermediate 3 (tert-butyl 1-(2-amino-6-chloropyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate

[0297]

[0298] 4,6-dichloropyrimidine-2-amine intermediate 1 (2g, 12.27mmol) is added to the stirring solution of N-(azetidine-3-yl)-N-methylcarbamic acid tert-butyl ester hydrochloride intermediate 2 (3.0g, 12.9mmol) in EtOH (50mL) in batches at RT, followed by addition of Et3N (8mL, 30.6mmol). The obtained suspension is heated to reflux and kept for 2h. The mixture is cooled, and water (30mL) is added dropwise. The obtained solid is separated, washed with water and dried to give (1-(2-amino-6-chloropyrimidine-4-yl)azetidine-3-yl) (methyl) carbamic acid tert-butyl ester intermediate 3 (3g, 79%) as a white solid. The data of intermediate 3 are in table 2.

[0299] General synthesis procedure:

[0300] Route A

[0301] Typical procedures for the preparation of pyrimidines, as exemplified by the preparation of Example 14-(1-(difluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine

[0302]

[0303] Tert-butyl (1-(2-amino-6-chloropyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate Intermediate 3 (0.350 g, 1.11 mmol), 1-(difluoromethyl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole Intermediate 4 (0.300 g, 1.23 mmol), K3PO4 (0.711 g, 3.36 mmol) were dissolved in 1,4-dioxane (4 mL) and water (1 mL), and the RM was degassed for 15 min. Pd(dppf)Cl2.DCM Intermediate 5 (0.090 g, 0.11 mmol) was added, and the RM was stirred at 70°C for 16 h. The reaction was diluted with water (10 mL), extracted with ethyl acetate (3×20 mL), the combined organic layers were dried (Na 2 SO 4 ), filtered and concentrated to give a crude residue which was purified by column chromatography (neutral alumina, 0%-35% EtOAc:hexanes) to give tert-butyl (1-(2-amino-6-(1-(difluoromethyl)-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (0.4 g, 90.7%) as an off-white solid.

[0304] LCMS (System 1, Method 1): m / z 395 (M+H)+ (ESI+ve) at 2.88 min, 220 nm.

[0305] Tert-butyl (1-(2-amino-6-(1-(difluoromethyl)-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (0.400 g, 0.10 mmol) was dissolved in DCM (4 mL), TFA (2 mL) was added dropwise at 0° C., and the RM was stirred at room temperature for 3 h. The solvent was evaporated in vacuo and azeotroped with toluene (3×10 mL) to give a crude residue, which was purified by purification method A to give the di-TFA salt of 4-(1-(difluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine Example 1 as a white solid (245 mg, 82.0%). The data for Example 1 are in Table 3.

[0306] Route B

[0307] Typical procedures for the preparation of pyrimidines, as exemplified by the preparation of Example 4 4-(1-(difluoromethyl)-3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine and Example 16 4-(1-(difluoromethyl)-5-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine

[0308]

[0309] 5-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole intermediate 8 (1.0 g, 4.81 mmol) was dissolved in acetonitrile (10 mL), 18-crown-6 intermediate 10 (254 mg, 0.96 mmol) and sodium difluorochloroacetate intermediate 9 (879 mg, 5.77 mmol) were added, and the reaction mixture was heated at 80 °C for 24 h. After cooling, the precipitate was removed by filtration and the filtrate was concentrated to give the crude product, which was purified by column chromatography (neutral alumina, 0% to 35% ethyl acetate in hexanes) to give a mixture of 1-(difluoromethyl)-5-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole and 1-(difluoromethyl)-3-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole as an off-white solid (combined 1 g, 80.6%).

[0310] LCMS (System 2, Method 2): Isomer 1, UV only at 3.52 min, 202 nm and Isomer 2, UV only at 3.63 min, 202 nm.

[0311] 1-(Difluoromethyl)-5-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole and 1-(difluoromethyl)-3-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (combined 1 g, 3.87 mmol) and tert-butyl (1-(2-amino-6-chloropyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate Intermediate 3 (1.1 g, 3.50 mmol) were dissolved in 1,4-dioxane (10 mL) at RT. Water (2 mL), K3PO4 (2.23 g, 10.51 mmol) were added, and the mixture was degassed for 15 min. PdCl2(dppf).DCM Intermediate 5 (280 mg, 0.35 mmol) was added and the mixture was stirred at 70°C for 16 h. The reaction mixture was partitioned between H2O (50 mL) and ethyl acetate (35 mL), the aqueous layer was further extracted with ethyl acetate (2×35 mL), the combined organic layers were dried (Na2SO4), filtered, and the solvent was concentrated to give a crude residue that was purified by column chromatography (neutral alumina, 0% to 2% methanol in DCM) to give a mixture of tert-butyl (1-(2-amino-6-(1-(difluoromethyl)-5-methyl-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate and tert-butyl (1-(2-amino-6-(1-(difluoromethyl)-3-methyl-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate as a yellow gum (630 mg combined, 39.7%).

[0312] LCMS (System 2, Method 2): Isomer 1, m / z 410.2 (M+H)+ (ES+) at 3.35 min, 202 nm and Isomer 2, m / z 410.2 (M+H)+ (ES+) at 3.40 min, 202 nm.

[0313] Tert-butyl (1-(2-amino-6-(1-(difluoromethyl)-5-methyl-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate and tert-butyl (1-(2-amino-6-(1-(difluoromethyl)-3-methyl-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (combined 800 mg, 1.95 mmol) were dissolved in DCM (8 mL) at 0°C, TFA (4 mL) was added dropwise, and the mixture was stirred at room temperature for 3 h. The reaction mixture was concentrated and the crude residue was azeotroped with toluene (3×5 mL) to give the crude product, which was purified by purification method D to give 4-(1-(difluoromethyl)-3-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine TFA salt Example 4 (362 mg, 43.8%) as a white solid and 4-(1-(difluoromethyl)-5-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine TFA salt Example 16 (150 mg, 18.1%) as a white solid. The data for Example 4 and Example 16 are in Table 3.

[0314] Route C

[0315] Typical procedures for the preparation of pyrimidines, as exemplified by the preparation of Example 5 (R)-4-(5-chloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)pyrrolidin-1-yl)pyrimidin-2-amine

[0316]

[0317] 5-Chloro-1-methyl-1H-pyrazole-4-carboxylic acid intermediate 11 (1.0 g, 6.25 mmol) was dissolved in THF (50 mL) and cooled to 0° C. Carbonyl diimidazole (1.51 g, 9.37 mol) was added under vigorous stirring, and the mixture was stirred at RT for 1 h. The reaction mixture was cooled to 0° C., ethyl malonate potassium salt intermediate 12 (1.59 g, 9.37 mol) and magnesium chloride intermediate 13 (0.89 g, 9.37 mol) were added, and the reaction mixture was stirred at RT for 16 h. The solvent was evaporated under reduced pressure, the reaction mixture was diluted with H2O (50 mL), acidified by addition of 1 M HCl solution (10 mL), extracted with EtOAc (3×100 mL), the combined organic layers were washed with brine solution (50 mL), dried over Na2SO4 and concentrated to give ethyl 3-(5-chloro-1-methyl-1H-pyrazol-4-yl)-3-oxopropanoate (1.01 g, 70%) as an off-white solid.

[0318] LCMS (System 2, Method 2): m / z 231.1 (M+H)+ (ES+) at 2.63 min, 254 nm.

[0319] Ethyl 3-(5-chloro-1-methyl-1H-pyrazol-4-yl)-3-oxopropanoate (0.9 g, 3.9 mmol) was dissolved in MeOH (15.0 mL) at 0° C., potassium tert-butoxide (1.31 g, 11.7 mmol) and guanidine hydrochloride intermediate 14 (0.743 g, 7.82 mmol) were added, and the reaction mixture was heated at 70° C. for 16 h. After cooling to RT, the solvent was evaporated under reduced pressure to give a yellow solid, which was suspended in water (50 mL), acidified by adding 1 M HCl solution (10 mL), extracted with DCM (3×50 mL), and the combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure to give 2-amino-6-(5-chloro-1-methyl-1H-pyrazol-4-yl)pyrimidin-4-ol (0.8 g, 91%) as an off-white solid.

[0320] LCMS (System 2, Method 2): m / z 226.1 (M+H)+ (ES+) at 1.81 min, 230 nm.

[0321] To a microwave vial containing 2-amino-6-(5-chloro-1-methyl-1H-pyrazol-4-yl)pyrimidin-4-ol (0.8 g, 3.5 mmol) was added phosphorus oxychloride (3.0 mL) at 0°C and the resulting solution was heated at 70°C for 16 h. The reaction mixture was cooled to RT, poured into ice-cold water (20 mL), the aqueous layer was neutralized by adding solid NaHCO3 and extracted with EtOAc (3×50 mL). The combined organic layers were washed with brine (100 mL), dried over Na2SO4 and concentrated to give 4-chloro-6-(5-chloro-1-methyl-1H-pyrazol-4-yl)pyrimidin-2-amine (0.38 g, 44%) as a white solid.

[0322] LCMS (System 2, Method 1): m / z 244.1 (M+H)+ (ES+) at 2.54 min, 240 nm.

[0323] 4-Chloro-6-(5-(trifluoromethyl)-1H-pyrazol-3-yl)pyrimidin-2-amine (0.18 g, 0.74 mmol) and (R)-tert-butyl methyl(pyrrolidin-3-yl)carbamate Intermediate 15 (0.296 g, 1.48 mol) were dissolved in Et3N (5.0 mL) in a 35 mL microwave vial, and the resulting mixture was heated at 120°C for 16 h. After that, the reaction mixture was cooled to RT, DCM (100 mL) was added, the organic layer was washed with H2O (50 mL) and brine solution (50 mL) and concentrated to get the crude product, which was purified by column chromatography (silica gel 60-120, 0%-5% MeOH in DCM) to give (R)-tert-butyl(1-(2-amino-6-(5-chloro-1-methyl-1H-pyrazol-4-yl)pyrimidin-4-yl)pyrrolidin-3-yl)(methyl)carbamate (0.230 g, 76%) as a brown viscous gum.

[0324] LCMS (System 2, Method 1): m / z 408.2 (M+H)+ (ES+) at 3.19 min, 254 nm.

[0325] (R)-tert-Butyl(1-(2-amino-6-(5-chloro-1-methyl-1H-pyrazol-4-yl)pyrimidin-4-yl)pyrrolidin-3-yl)(methyl)carbamate (0.23 g, 0.57 mmol) was dissolved in DCM (1.0 mL), TFA (1.0 mL) was added at 0° C., and the reaction mixture was stirred at RT for 1 h. The solvent was evaporated under reduced pressure, and the residue was purified by purification method E to give (R)-4-(5-chloro-1-methyl-1H-pyrazol-4-yl)-6-(3-(methylamino)pyrrolidin-1-yl)pyrimidin-2-amine Example 5 (35 mg, 20%) as a white solid. The data for Example 5 are in Table 3.

[0326] Route D

[0327] Typical procedures for the preparation of pyrimidines, as exemplified by the preparation of Example 19 4-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine

[0328]

[0329] 3-Methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazole-4-carboxylic acid intermediate 27 (1.0 g, 4.8 mmol) was dissolved in dry THF (100 mL) under N2 gas, and the solution was cooled to 0°C. Carbonyl diimidazole (1.6 g, 9.6 mmol) was added, and the mixture was stirred at RT for 1 h. The reaction mixture was cooled to 0°C, ethyl malonate potassium salt intermediate 12 (1.63 g, 9.6 mmol) and magnesium chloride intermediate 13 (0.9 g, 9.6 mmol) were added, and the reaction mixture was stirred at RT for 16 h. Afterwards, the solvent was evaporated, the residue was diluted with H2O (50 mL), and the aqueous layer was acidified by adding 1N HCl solution (20 mL) and extracted with EtOAc (3×100 mL). The combined organic layers were washed with brine solution (50 mL), dried over Na2SO4 and concentrated to give the crude product, which was purified by column chromatography (silica gel; 60-120 mesh; 0%-40% EtOAc in hexanes) to afford ethyl 3-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)-3-oxopropanoate (0.52 g, 40%) as an off-white solid.

[0330] LCMS (System 2, Method 2): m / z 277.0 (M+H)+ (ES+) at 2.84 min, 244 nm.

[0331] Ethyl 3-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)-3-oxopropanoate (0.5 g, 1.79 mol) was dissolved in MeOH (15 mL) at 0°C, potassium tert-butoxide (0.6 g, 0.00539 mol) and guanidine hydrochloride intermediate 14 (0.345 g, 3.59 mmol) were added, and the reaction mixture was heated at 70°C for 16 h. After that, the solvent was evaporated to get a yellow solid, which was suspended in water (50 mL), acidified by adding 1 M HCl solution (10 mL), extracted with DCM (3×50 mL), the combined organic layers were dried over Na 2 SO 4 and concentrated under reduced pressure to give 2-amino-6-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)pyrimidin-4-ol (0.38 g, 77%) as an off-white solid.

[0332] LCMS (System 2, Method 2): m / z 274.2 (M+H)+ (ES+) at 1.85 min, 240 nm.

[0333] 2-Amino-6-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)pyrimidin-4-ol (0.38 g, 1.39 mmol) and tert-butyl azetidin-3-yl(methyl)carbamate Intermediate 2 (0.463 g, 2.08 mmol) were dissolved in Et3N (5.0 mL) and MeCN (8.0 mL) at 0° C. PYBOP Intermediate 34 (1.08 g, 2.08 mmol) was added at 0° C. and the reaction mixture was heated at 80° C. for 16 h. After that, the reaction mixture was cooled to RT, DCM (100 mL) was added, the organic layer was washed with H2O (50 mL) and brine solution (50 mL), and the solvent was concentrated to give the crude product, which was purified by column chromatography (silica gel 60 mesh-120 mesh, 0%-5% MeOH in DCM) to give tert-butyl (1-(2-amino-6-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (0.410 g, 66%) as a brown viscous gum.

[0334] LCMS (System 2, Method 1): m / z 442.3 (M+H)+ (ES+) at 3.03 min, 214 nm.

[0335] Tert-butyl (1-(2-amino-6-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (0.41 g, 0.929 mmol) was dissolved in DCM (2.0 mL) at 0°C, TFA (2.0 mL) was added, and the reaction mixture was stirred at RT for 1 h. The solvent was evaporated under reduced pressure, and the residue was purified by purification method R to give 4-(3-methyl-1-(2,2,2-trifluoroethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine Example 19 (27 mg, 33%) as a white solid. The data for Example 19 are in Table 3.

[0336] Route E

[0337] Typical procedures for the preparation of pyrimidines, as exemplified by the preparation of Example 36 4-(3-(methylamino)azetidin-1-yl)-6-(1H.pyrazol-3-yl)pyrimidin-2-amine

[0338]

[0339] 4,6-Dichloropyrimidin-2-amine intermediate 1 (1 g, 12.0 mmol), 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole intermediate 44 (1.40 g, 7.20 mmol) and K3PO4 (3.88 g, 18.9 mmol) were dissolved in 1,4-dioxane (20 mL) and water (4 mL) under nitrogen and degassed for 20 min. Pd(dppf)Cl2.DCM intermediate 5 (497 mg, 0.60 mmol) was added and the reaction mixture was stirred at 80°C for 16 h. After cooling, the reaction mixture was diluted with water (50 mL), extracted with ethyl acetate (3×50 mL), the combined organics were dried (Na 2 SO 4 ), filtered and concentrated to give a crude residue, which was purified by column chromatography (silica gel; 60-120 mesh, 0%-28% EtOAc in hexanes) to give 4-chloro-6-(1H-pyrazol-3-yl)pyrimidin-2-amine (230 mg, 19.5%) as an off-white solid.

[0340] LCMS (System 1, Method 1): m / z 196 (M+H)+ (ES+) at 2.62 min, 254 nm.

[0341] 4-Chloro-6-(1H-pyrazol-3-yl)pyrimidin-2-amine (210 mg, 1.0 mmol) and tert-butyl azetidin-3-yl(methyl)carbamate hydrochloride intermediate 2 (401 mg, 2.1 mmol) were dissolved in MeCN (10 mL), Et3N (4 mL) was added and the reaction was stirred at 90°C for 6 h. The reaction mixture was cooled, diluted with water (30 mL), extracted with ethyl acetate (3 x 30 mL), the combined organics were dried (Na2SO4), filtered and concentrated to give crude tert-butyl (1-(2-amino-6-(1H-pyrazol-3-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (assumed 100%) as an off-white solid which was used crude without purification.

[0342] LCMS (System 1, Method 1): m / z 346 (M+H)+ (ES+) at 2.98 min, 240 nm.

[0343] Tert-butyl (1-(2-amino-6-(1H-pyrazol-3-yl)pyrimidin-4-yl)azetidine-3-yl)(methyl)carbamate (570 mg, 1.6 mmol) was dissolved in DCM (3 mL) at 0°C, TFA (1.5 mL) was added dropwise, and the reaction mixture was stirred at room temperature for 3 h. The solvent was concentrated, and the residue was azeotroped with toluene (3×3 mL) to give a crude product, which was purified by Purification Method AI to give 4-(3-(methylamino)azetidine-1-yl)-6-(1H-pyrazol-3-yl)pyrimidin-2-amine Example 36 (151 mg, 37.3%) as a white solid. The data for Example 36 are in Table 3.

[0344] Route F

[0345] Procedure for the Preparation of Example 20 4-(3-methyl-1-(trifluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine and Example 23 4-(5-methyl-1-(trifluoromethyl)-1H-pyrazol-4-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine

[0346]

[0347] Route G

[0348] Procedure for the Preparation of Example 32 4-(3-(methylamino)azetidin-1-yl)-6-(1-(trifluoromethyl)-1H-pyrazol-4-yl)pyridin-2-amine and Example 33 (R)-4-(3-(methylamino)pyrrolidin-1-yl)-6-(1-(trifluoromethyl)-1H-pyrazol-4-yl)pyridin-2-amine

[0349]

[0350] For the synthesis of Example 33, Intermediate 17 was used instead of Intermediate 2.

[0351] Route H

[0352] Procedure for the Preparation of Example 40 4-(5-ethyl-4-methyl-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidin-1-yl)pyrimidin-2-amine

[0353]

[0354] 5-ethyl-4-methyl-1H-pyrazole-3-carboxylic acid intermediate 53 (0.75 g, 4.87 mmol) was dissolved in dry THF (100 mL), and the solution was cooled to 0° C. Carbonyl diimidazole (1.57 g, 9.74 mmol) was added under vigorous stirring, and the mixture was stirred for 1 h at RT. The reaction mixture was cooled to 0° C., followed by addition of ethyl malonate potassium salt intermediate 12 (1.62 g, 9.74 mmol) and magnesium chloride intermediate 13 (0.935 g, 9.74 mol), and the reaction mixture was stirred overnight at RT. After completion of the reaction, the solvent was evaporated under reduced pressure, the reaction mixture was diluted with H2O (50 mL), the aqueous layer was acidified by addition of 1N HCl solution (30 mL), extracted with EtOAc (3×100 mL), and the combined organic layers were washed with brine solution (50 mL), dried over Na2SO4, filtered and concentrated to give the crude product, which was purified by column chromatography (silica gel; 60 mesh-120 mesh; 0%-40% EtOAc / hexane) to give ethyl 3-(5-ethyl-4-methyl-1H-pyrazol-3-yl)-3-oxopropanoate (0.71 g, 65%) as an off-white solid.

[0355] LCMS (System 1, Method 2): m / z 225.3 (M+H)+ (ES+) at 2.80 min, 240 nm.

[0356] Ethyl 3-(5-ethyl-4-methyl-1H-pyrazol-3-yl)-3-oxopropanoate (0.7 g, 3.12 mmol) was dissolved in MeOH (15 mL), potassium tert-butoxide (1.05 g, 9.37 mmol) and guanidine hydrochloride intermediate 14 (0.6 g, 6.25 mmol) were added at 0° C., the reaction mixture was heated to RT, and then heated at 70° C. overnight. After the reaction was completed, the reaction mixture was cooled to RT, the solvent was evaporated under reduced pressure to give a yellow solid, which was acidified by dropwise addition of 1N HCl (5 mL), and the aqueous layer was extracted with EtOAc (3×50 mL). The combined organic layers were washed with brine solution (50 mL), dried over Na2SO4 and concentrated under reduced pressure to give 2-amino-6-(5-ethyl-4-methyl-1H-pyrazol-3-yl)pyrimidin-4-ol (0.68 g, 99%) as an off-white solid.

[0357] LCMS (System 1, Method 2): m / z 220.3 (M+H)+ (ES+) at 1.81 min, 202 nm.

[0358] POCl (2.0 mL) was added to 2-amino-6-(5-ethyl-4-methyl-1H-pyrazol-3-yl)pyrimidin-4-ol (0.68 g, 3.1 mmol) at 0° C. and the reaction mixture was heated at 70° C. overnight. After completion of the reaction, the reaction mixture was poured into an ice bath, neutralized by adding solid NaHCO, the aqueous layer was extracted with EtOAc (3×50 mL), and the combined organic layers were washed with brine solution (50 mL), dried over NaSO, filtered and concentrated to give a crude residue, which was purified by column chromatography (silica gel; 60-120 mesh; 0%-40% EtOAc / hexanes) to give 4-chloro-6-(5-ethyl-4-methyl-1H-pyrazol-3-yl)pyrimidin-2-amine (401 mg, 54%) as a yellow solid.

[0359] LCMS (System 2, Method 2): m / z 238.3 (M+H)+ (ES+) at 2.75 min, 214 nm.

[0360] 4-Chloro-6-(5-ethyl-4-methyl-1H-pyrazol-3-yl)pyrimidin-2-amine (189 mg, 7.97 mmol) and tert-butyl azetidin-3-yl(methyl)carbamate Intermediate 2 (0.354 g, 1.59 mmol) were dissolved in triethylamine (5.0 mL) and the reaction mixture was heated at 120° C. overnight. After completion of the reaction, the reaction mixture was cooled to RT, DCM (100 mL) was added, the organic layer was washed with H2O (50 mL), brine (50 mL) and concentrated to give the crude product, which was purified by column chromatography (silica gel 60 mesh-120 mesh, 0%-5% MeOH:DCM) to give tert-butyl (1-(2-amino-6-(5-ethyl-4-methyl-1H-pyrazol-3-yl)pyrimidin-4-yl)azetidin-3-yl)(methyl)carbamate (230 mg, 74%) as a brown viscous gum.

[0361] LCMS (System 2, Method 1): m / z 273.3 (M+H)+ (ES+) at 3.03 min, 202 nm.

[0362] Tert-butyl (1-(2-amino-6-(5-ethyl-4-methyl-1H-pyrazol-3-yl)pyrimidin-4-yl)azetidine-3-yl)(methyl)carbamate (230 mg, 5.94 mmol) was dissolved in DCM (2.0 mL), TFA (2.0 mL) was added at 0° C. and the reaction mixture was stirred at RT for 1 h. The solvent was evaporated under reduced pressure and the obtained crude product was purified by preparative HPLC to give 4-(5-ethyl-4-methyl-1H-pyrazol-3-yl)-6-(3-(methylamino)azetidine-1-yl)pyrimidin-2-amine Example 40, ditrifluoroacetate (33 mg, 19%) as a white solid. The data for Example 40 are in Table 3.

[0363] Table 2 - Intermediates

[0364]

[0365]

[0366]

[0367]

[0368]

[0369]

[0370]

[0371]

[0372]

[0373]

[0374]

[0375] Biological Activity

[0376] Example A

[0377] H4 antagonist functional cAMP Gi assay

[0378] HEKf cells were infected overnight using a baculovirus expressing the human H4 receptor, then centrifuged at 1,200 rpm for 5 min, frozen in cell freezing medium (Sigma), and stored at -150°C. On the day of the assay, cells were thawed and resuspended in HBSS with 500 nM IBMX to a density of 1,500 cells / well. H4 ligands were prepared in DMSO and stamped with 25 nL by LabCyte ECHO acoustic distribution in a low-volume plate. Cells were plated at 10 μL / well in the presence of 1 μM forskolin, subjected to centrifugation at 1,200 rpm for 1 min, and incubated for 30 min before adding Cisbio cAMP detection reagent to a total volume of 20 μL / well. For antagonist assays, cells were pre-incubated with H4 antagonist ligands for 30 min, then histamine at an EC80 concentration was added, and incubated for another 30 min. After adding the detection reagent and shaking at room temperature for 60 min, cAMP accumulation was measured on a PheraStar plate reader using HTRF. A 4-parameter logistic fit equation was used to quantify agonist potency to generate EC50 values. Functional antagonist affinity values ​​were generated using the Cheng-Prusoff equation to calculate pKb values ​​using antagonist assay data.

[0379] H4 antagonist functional dynamic mass redistribution assay

[0380] HEKf cells were infected with baculovirus expressing human H4 receptors, plated at a density of 10,000 cells / well into fibronectin-coated EPIC plates, and incubated overnight at 37°C. The culture medium on the cells was changed to 30 μL of HBSS with 20 mM HEPES per well, and 30 nL of DMSO was added to each well by LabCyte ECHO acoustic dispensing. After 2 h of equilibration at room temperature, 30 nL of H4 ligand prepared in DMSO was punched into the inoculated EPIC plates by LabCyte ECHO acoustic dispensing, and the dynamic mass redistribution of cells was monitored using a Corning EPIC plate reader. After 45 min of measurement, 30 nL / well of histamine EC80 was added and monitored to obtain antagonist assay data. The maximum baseline-corrected response in pm was used to generate concentration-response curves. A 4-parameter logistic fit equation was used to quantify agonist potency to generate EC50 values. Functional antagonist affinity values ​​were generated using the Cheng-Prusoff equation to calculate pKb values ​​using antagonist assay data.

[0381] hERG assay

[0382] hERG assay data were determined by Metrion Biosciences, Cambridge, UK using the protocol detailed below:

[0383] A Chinese hamster ovary (CHO) cell line stably expressing the human ether-á-go-related gene was grown and passaged under standard culture conditions. Cells were prepared for the assay using a dissociation protocol designed to optimize cell health, yield and sealing, and assay quality. Test samples were provided as 10 mM stock solutions in 100% DMSO. All sample handling and serial dilutions were performed using glass containers and glass-lined plates. A maximum working concentration of 30 μM was prepared from the 10 mM sample stock solution using a 1:333-fold dilution into external recording solution (0.3% DMSO v / v). In single concentration assays, test samples were screened at 30 μM against at least three individual cells. 50 In the assay, test samples were screened against at least three separate cells at 1 μM, 3 μM, 10 μM and 30 μM. Each four-point concentration response curve was constructed using two cumulative additions of each concentration of sample to the same cells.

[0384] All experiments were performed on the QPatch automated patch clamp platform. The composition of the external and internal recording solutions for the QPatch experiments are shown below in Table A. All solutions were filtered (0.2 μm) before each experiment.

[0385] Table A: Composition of external and internal solutions used in hERG studies (in mM)

[0386]

[0387] All recordings were performed in conventional whole-cell configuration and at room temperature (~21°C) using standard single-well chips (Rchip 1.5-4MΩ). Series resistance (4-15MΩ) was compensated >80%. Current was drawn from a holding potential of -90mV using an industry standard "+40 / -40" voltage protocol as shown below; this was applied at a stimulation frequency of 0.1Hz.

[0388]

[0389] QPatch voltage protocol for hERG assay.

[0390] For achieving whole-cell configuration, vehicle (0.3% DMSO v / v in external recording solution) was applied to each cell in two bolus additions with a two-minute recording period between each addition to allow for stable recordings to be achieved. After the vehicle period:

[0391] i) For single concentration assays - a single concentration of test sample is applied at 30 μM as five additions per test concentration at two minute intervals; or

[0392] ii) For pIC 50 Four concentrations of the test sample from 1 μM to 30 μM were applied as two additions per test concentration at two-minute intervals;

[0393] And then measure the influence on hERG tail current amplitude during the four-minute recording period.For each scan of the voltage protocol, the membrane current and passive properties of individual cells are recorded by QPatch determination software.The peak outward tail current amplitude drawn during the test pulse to -40mV is measured relative to the instantaneous leakage current measured during the initial pre-pulse step to -40mV.For QC purposes, the minimum current amplitude of the assay is the peak outward current of >200pA measured at the end of the vehicle phase.QPatch analysis software calculates the average peak current of the last three scans at the end of each concentration application phase, and the data are exported to Excel, and the bioinformatics suite of the development run in Pipeline Pilot (Biovia, USA) is used for query.The template calculates the inhibition percentage of the reduction of the average peak current or charge of the value measured at the end of the control (i.e., vehicle) phase as each test concentration application phase. The percent inhibition values ​​from each cell were used to construct concentration-response curves using a four-parameter logistic fit with fixed 0% and 100% inhibition levels at very low and very high concentrations, respectively, and a free Hill slope factor. The IC 50 (50% inhibitory concentration) and Hill coefficient, but only data for cells with a Hill slope within 0.5>nH<2.0 are included. The IC reported below 50 Data represent the mean of at least three individual cells (N≥3). By convention, samples tested that did not achieve >40% blocking at the highest concentration would yield an ambiguous IC 50 values, which is due to a poor or unconstrained fit. In this case, any IC 50 Values ​​are returned that are 0.5 log units higher than the highest concentration tested. For example, if a sample does not show a mean inhibition of >40% blocking at the highest concentration of 30 μM, an IC of 100 μM is reported. 50Value, i.e. pIC 50 ≤4.0.

[0394]

[0395]

[0396] 1 Changlu Liu et al., J Pharmacol Exp Ther., 299, (2001), 121-130.

[0397] 2 Jennifer D. Venable et al., J. Med. Chem., 48, (2005), 8289-8298.

[0398] 3 Brad M. Savall et al., J. Med. Chem., 57, (2014), 2429-2439.

[0399] 4 Robin L Thurmond et al., Ann Pharmacol Pharm., 2, (2017), 1-11.

[0400] 5 Charles E. Mowbray et al., Bioorg. Med. Chem. Lett., 21, (2011), 6596-6602.

[0401] 6 Rogier A. Smits et al., Bioorg. Med. Chem. Lett., 23, (2013), 2663-2670.

[0402] 7 Chan-Hee Park et al., J. Med. Chem., 61, (2018), 2949-2961.

[0403] This article also provides the following items:

[0404] 1. A compound selected from the group consisting of:

[0405]

[0406]

[0407] or a salt thereof.

[0408] 2. The compound according to item 1, which is selected from the group consisting of:

[0409]

[0410]

[0411] or a salt thereof.

[0412] 3. A pharmaceutically acceptable salt of the compound according to item 1 or 2.

[0413] 4. A pharmaceutical composition comprising a compound as defined in any one of items 1 to 3 and a pharmaceutically acceptable excipient.

[0414] 5. A compound according to any one of items 1 to 3 or a composition according to item 4 for use in medicine.

[0415] 6. The compound according to item 1, which has H4 receptor activity.

[0416] 7. The compound according to item 6, which exhibits low hERG activity.

[0417] 8. A compound or composition according to any one of items 1 to 7 for use in the treatment of inflammatory disorders including asthma, chronic pruritus, dermatitis, rheumatoid arthritis, gastric ulcerogenesis and colitis.

Claims

1. A compound selected from the group consisting of: or a salt thereof.

2. The compound or salt thereof according to claim 1, wherein the compound or salt thereof is selected from the group consisting of: or a salt thereof.

3. A pharmaceutically acceptable salt of a compound as defined in claim 1 or claim 2.

4. A pharmaceutical composition comprising the compound or salt thereof according to claim 1 or 2 or the pharmaceutically acceptable salt according to claim 3 and a pharmaceutically acceptable excipient.

5. A compound according to claim 1 or 2 or a salt thereof, or a pharmaceutically acceptable salt according to claim 3, or a pharmaceutical composition according to claim 4, for use in medicine. The compound or a salt thereof according to claim 1, having H4 receptor activity. 7 . The compound or salt thereof according to claim 6 , which exhibits low hERG activity.

8. Use of a compound or salt thereof according to any one of claims 1, 2, 6 and 7, or a pharmaceutically acceptable salt according to claim 3, or a pharmaceutical composition according to claim 4, for the preparation of a medicament for the treatment of inflammatory disorders including asthma, chronic pruritus, dermatitis, rheumatoid arthritis, gastric ulcerogenesis or colitis.

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