Helicase bis-cyclic amide derivatives and uses thereof

Abstract

Disclosed herein are specific helicase bicyclic amide derivatives of Formula (I): which inhibit DNA polymerase theta (Polθ) activity, in particular by inhibiting the ATP-dependent helicase domain activity of Polθ. In addition, pharmaceutical compositions comprising such compounds are disclosed, as well as methods of treating and / or preventing diseases that can be treated by inhibiting Polθ, such as cancer, including homologous recombination (HR)-deficient cancer.

Description

Technical Field

[0001] This article discloses specific helicase bicyclic amide derivatives that inhibit DNA polymerase θ (Polθ) activity, particularly by inhibiting the activity of the ATP-dependent helicase domain of Polθ. Additionally, pharmaceutical compositions comprising such compounds and methods for treating and / or preventing diseases (e.g., cancers, including homologous recombination (HR)-deficient cancers) that can be treated by inhibiting Polθ are disclosed. Background Technology

[0002] Targeting DNA repair defects has become a proven and effective strategy in cancer treatment. However, cancers with DNA repair defects often become dependent on alternative DNA repair pathways, which become the "Achilles' heel" that can be targeted to eliminate cancer cells and are the basis of synthetic lethality. The success of poly(ADP-ribose) polymerase (PARP) inhibitors in treating BRCA-deficient breast and ovarian cancers is an example of synthetic lethality.

[0003] DNA damage repair processes are crucial for genome maintenance and stability. Double-strand breaks (DSBs) are primarily repaired via the non-homologous end joining (NHEJ) pathway during the G1 phase of the cell cycle and via homologous recombination (HR) during the S-G2 phase. A less-discussed alternative end joining (alt-EJ), also known as microhomologous-mediated end joining (MMEJ), is generally considered a "backup" DSB repair pathway when NHEJ or HR is blocked. Numerous genetic studies have highlighted the role of DNA polymerase θ (Polθ, derived from DNA polymerase θ). POLQ The role of coding in the stimulation of MMEJ in higher organisms.

[0004] Polθ is unique among human DNA polymerases, exhibiting both a C-terminal DNA polymerase domain and an N-terminal helicase domain, separated by a long, less conserved central domain whose function is unknown except for Rad51 binding. The N-terminal ATPase / helicase domain belongs to the JJELQ class within the SF2 helicase superfamily. In homologous recombination-deficient (HRD) cells, Polθ can synthesize error-prone DNA at DNA damage sites via the alternative EJ pathway. Studies show that Polθ's helicase domain inhibits the HR pathway by disrupting the formation of the Rad51 nucleoprotein complex, which is involved in the initiation of HR-dependent DNA repair responses after ionizing radiation. This anti-recombinase activity of Polθ promotes the alternative EJ pathway. Furthermore, Polθ's helicase domain also facilitates microhomology-mediated strand annealing. When ssDNA overhangs contain >2 bp microhomologies, Polθ can efficiently promote end joining in the alternative EJ pathway by utilizing this annealing activity. This re-annealing activity is achieved through a coupling of Rad51 interaction and subsequent ATPase-mediated translocation of Rad51 from the DSB lesion site. Once annealing is complete, the DNA primer strand can be extended by the polymerase domain of Polθ.

[0005] Polθ expression is essentially absent in normal cells but is upregulated in breast, lung, and ovarian cancers. Furthermore, increased Polθ expression is associated with poor prognosis in breast cancer. Studies have shown that cancer cells with deficiencies in HR, NHEJ, or ATM are highly dependent on Polθ expression. Therefore, Polθ is a highly attractive target for novel synthetic lethal therapies in cancers with DNA repair defects.

[0006] WO2020243459A1, WO2022259204, WO2022118210A1, and WO2023067515A disclose several Polθ inhibitors. However, Polθ inhibitors are not currently marketed in any country. Compounds that inhibit Polθ activity still need to be developed. Summary of the Invention

[0007] This document discloses specific helicase bicyclic amide derivatives of formula (I) that inhibit Polθ activity, particularly by inhibiting the activity of the ATP-dependent helicase domain of Polθ. Additionally, pharmaceutical compositions comprising such compounds and methods for treating and / or preventing diseases (e.g., cancers, including homologous recombination (HR)-deficient cancers) that can be treated by inhibiting Polθ are disclosed. Detailed Implementation

[0008] Before further describing the invention, it should be understood that the invention is not limited to the specific embodiments described herein, and it should also be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the invention.

[0009] I. Compounds In one respect, compounds of formula (I) are provided: (I) Or its tautomers, stereoisomers, or pharmaceutically acceptable salts. in: Ring A is a 5-10 aryl or heteroaryl group containing 1 to 4 atoms Y, which are independently selected from carbon, nitrogen, oxygen or sulfur; R 11 and R 12 Independently absent or independently selected from hydrogen, alkyl, halogen, haloalkyl, haloalkoxy, alkoxy, hydroxy, cyano, cyanoalkyl, carboxyl, alkoxycarbonyl, acylamino, aminocarbonyl, optionally substituted heteroaryl, hydroxyalkyl, cycloalkyl, hydroxyynyl, alkoxyalkyl, aminoalkyl, aminocarbonylalkyl, sulfonylalkyl, aminosulfonylalkyl, optionally substituted heteroaryl or optionally substituted heterocyclic alkyl, wherein m and n are independently integers from 0 to 10; Ar1 is a phenyl, heteroaryl, heterocyclic, bicyclic, bridged heterocyclic, or spirocyclic group, wherein each of the above rings is R a R b R c and R d Replace, where R a R b R c and R d Independently absent or independently selected from hydrogen, alkyl, halogen, haloalkyl, alkoxy, haloalkoxy, cycloalkyloxy, acyl, acylamino, monoalkylamino, dialkylamino, alkylsulfonyl, cyano, and hydroxyl; Cycle B is a 5-10 aryl or heteroaryl group containing 1-4 Y atoms independently selected from carbon, nitrogen, oxygen or sulfur, or a 4-10 saturated or unsaturated lactam, preferably a 5-7 saturated or unsaturated lactam. Optionally, cycle B is further substituted with an alkyl group, a halogen or a haloalkyl group. G is a branched or unbranched, substituted or unsubstituted, saturated or unsaturated aliphatic hydrocarbon chain having 1-20 carbon atoms in its skeletal chain, or a heteroatom independently selected from nitrogen, oxygen or sulfur. If G is nitrogen, it is substituted. R 21It is absent or selected from hydrogen, alkyl, halogen, haloalkyl, haloalkoxy, alkoxy, hydroxyl, cyano, cyanoalkyl, carboxyl, alkoxycarbonyl, amino, acylamino, aminocarbonyl, hydroxyalkyl, hydroxyynyl, alkoxyalkyl, optionally substituted aminoalkyl, aminocarbonylalkyl, sulfonylalkyl, aminosulfonylalkyl, optionally substituted alkoxyalkyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted cycloalkyl, optionally substituted phenyl, optionally substituted heteroaryl, optionally substituted heterocyclic, optionally substituted bicyclic heterocyclic, optionally substituted bridged heterocyclic, optionally substituted spirocyclic, or optionally substituted spirocyclic. Among them G, R 11 R 12 Or R 21 The substituents are independently selected from alkyl, cycloalkyl, cycloalkoxy, halogen, haloalkyl, haloalkoxy, alkoxy, alkoxyalkyl, hydroxy, carboxyl, and alkoxycarbonyl. Where R 11 R 12 Ar1 or R 21 The heteroatoms are independently selected from nitrogen, oxygen, or sulfur.

[0010] In some implementations, ring A is selected from the following: .

[0011] In some implementations, Ar1 is or , Where Z is selected from -N- or -C-; and R a R b R c and R d Independently absent or independently selected from hydrogen, alkyl, halogen, haloalkyl, alkoxy, haloalkoxy, cycloalkyloxy, acyl, acylamino, monoalkylamino, dialkylamino, alkylsulfonyl, cyano, and hydroxyl.

[0012] In some implementations, Ar1 is selected from the following: .

[0013] In some implementations, Ar1 is selected from the following: .

[0014] In some embodiments, ring B is a 5-6 aryl or heteroaryl group containing three atoms Y1, Y2, Y3, wherein Y1, Y2, Y3 are independently absent or selected from carbon, nitrogen, oxygen, or sulfur; and optionally each of Y1, Y2, Y3 is further independently oxidized by C. 1-6 Alkyl, halogen or C 1-6 Halogenated alkyl substitution; Preferably, ring B is Where Y1, Y2, and Y3 are independently absent or selected from carbon and nitrogen; and the bonds... It represents a single bond or a double bond.

[0015] In some implementations, the number and location of nitrogen atoms in ring B can affect solubility and metabolic stability in plasma.

[0016] In some implementations, formula I is selected from: ,key Represents a single or double bond. In some implementations, Z is preferably selected from -N-.

[0017] In some implementations, R 21 It does not exist or is selected from the following: .

[0018] In some implementations, ring A is ; Ar1 is Ra is selected from C 1-6 alkoxy groups; and R b R c and R d Independently selected from hydrogen, C 1-6 Alkyl, halogen, C 1-6 Halogenated alkyl groups; Ring B is Where Y1 is CH, Y2 is NH, and Y3 comes from CH or NH, and the bond... Represents a single or double bond; and G is oxygen; and optionally each of Y1 and Y3 is further independently constituting C. 1-6 Alkyl, halogen or C 1-6 Halogenated alkyl substitution; R 21 Selected from the replaced C 1-6 Alkyl and substituted C3-8 cycloalkyl; and R 21 The substituents are independently selected from C 3-8 Cycloalkoxy, C 1-6 Halogenated alkoxy groups and C 1-6 Alkyl group.

[0019] In some implementations, formula I is selected from: or Where Z is -N-; R 21 Selected from the replaced C 1-6 Alkyl and substituted C 3-8 cycloalkyl; and R 21 The substituents are independently selected from C 3-8 Cycloalkoxy, C 1-6 Halogenated alkoxy groups and C 1-6 alkoxy groups; and R b R c and R d Independently selected from hydrogen, C 1-6 Alkyl, halogen, C 1-6 Halogenated alkyl groups.

[0020] In some implementations, R in Formula I 21 Selected from the following: ;as well as Selected from the following: .

[0021] In some embodiments, the compounds are selected from Table 1 below.

[0022] Table 1

[0023] Or its tautomers, stereoisomers or pharmaceutically acceptable salts.

[0024] In some embodiments, the number and position of nitrogen in ring B affect solubility and metabolic stability in plasma. The cores of C-4 and C-35 exhibit superior solubility compared to C-34 / C-33 / C-36 (C-4 and C-35 have solubilities of 221 μM and 259 μM in PBS (pH 7.4), while C-34 / C-33 / C-36 have solubilities of 2 μM, 24 μM, and 48 μM in PBS (pH 7.4)). Furthermore, C-35 demonstrates better metabolic stability than C-34 (both C-35 have HH CLINT (human hepatocyte intrinsic clearance) and RHCLINT (rat hepatocyte intrinsic clearance) of 3 μL / min / 10 μL / min). 6 For C-34, the HH CLINT concentration is 9 μL / min / 10 μL. 6 RH CLINT is 11 μL / min / 10 6 ).

[0025] The core of C-35 is superior to that of C-55 in terms of solubility (C-35 has a solubility of 259 μM in PBS (pH 7.4), while C-55 has a solubility of 8 μM in PBS (pH 7.4)).

[0026] In some implementations, R 21 The methyl group is optionally replaced by one, two, or three deuterium groups; preferably, the compound is C-52 from Table 1. These compounds, deuterated at key metabolic sites, exhibit improved metabolic stability, such as a longer t0. 1 / 2 .

[0027] In some embodiments, the 1,3-thiazole of Formula I is derived to thiazol-3(2H)-yl)methyl dihydrophosphate, more preferably, the compound is C-53 in Table 1. These prodrugs are inactive in biochemical assays but active in cells.

[0028] II. Pharmaceutical Composition In another aspect, the present invention provides a pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable carrier.

[0029] In some embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof is present in a therapeutically effective amount. The pharmaceutical composition may be used in the methods disclosed herein; thus, for example, the pharmaceutical composition may be administered to a subject ex vivo or in vivo to perform the treatment methods and uses described herein.

[0030] In one particular variant, the composition is a solid dosage form suitable for oral administration. In another particular variant, the composition is a liquid dosage form suitable for oral administration. In yet another particular variant, the composition is a tablet. In still another particular variant, the composition is a liquid dosage form suitable for parenteral administration.

[0031] The present invention also provides a pharmaceutical composition comprising a compound according to any of the embodiments and variations described above, wherein the composition is suitable for administration via a route selected from: oral, parenteral, intraperitoneal, intravenous, intra-arterial, transdermal, sublingual, intramuscular, rectal, buccal, intranasal, liposome, via inhalation, vagina, intraocular, via local delivery (e.g., via catheter or stent), subcutaneous, intra-fat, intra-articular, and intrathecal.

[0032] III. Methods and Applications In another aspect, this disclosure provides a method for treating a disease characterized by overexpression of Polθ, comprising administering to a patient a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt.

[0033] In another aspect, this disclosure provides compounds of formula (I) or pharmaceutically acceptable salts thereof or pharmaceutical compositions thereof, which are used as medicaments for treating diseases characterized by overexpression of Polθ.

[0034] In another aspect, this disclosure provides the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof or a pharmaceutical composition thereof in the preparation of a medicament for treating a disease characterized by overexpression of Polθ.

[0035] In some implementations, the patient is identified as needing this treatment and the disease is cancer.

[0036] In some implementations, the cancer is homologous recombination (HR) defective cancer.

[0037] In some implementations, the cancer is characterized by reduced or absent BRCA gene expression, absence of BRCA genes, or reduced function of BRCA proteins.

[0038] In some implementations, the cancer is lymphoma, soft tissue cancer, rhabdomyosarcoma, multiple myeloma, uterine cancer, gastric cancer, peripheral nervous system cancer, rhabdomyosarcoma, bone cancer, colorectal cancer, mesothelioma, breast cancer, ovarian cancer, lung cancer, fibroblastic cancer, central nervous system cancer, urinary system cancer, upper respiratory and digestive tract cancer, leukemia, kidney cancer, skin cancer, esophageal cancer, and pancreatic cancer.

[0039] Application route Compounds of formula (I) or pharmaceutically acceptable salts thereof, and compositions comprising them, may be administered in any suitable manner. Suitable routes of administration include oral, parenteral (e.g., intramuscular, intravenous, subcutaneous (e.g., injection or implantation), intraperitoneal, intracerebellomedullary cistern, intra-articular, intraperitoneal, intracerebral (within brain parenchyma) and intraventricular), intranasal, vaginal, sublingual, intraocular, rectal, topical (e.g., transdermal), buccal, and inhalation. Compounds of formula (I) or pharmaceutically acceptable salts thereof may also be administered over a defined time period using reservoir-type injectable formulations typically administered subcutaneously or intramuscularly. Specific embodiments of the invention cover oral administration.

[0040] Combination therapy The present invention covers the use of compounds of formula (I) or pharmaceutically acceptable salts thereof in combination with one or more active therapeutic agents (e.g., chemotherapeutic agents) or other preventive or therapeutic means (e.g., radiation).

[0041] Dosage The compounds of formula (I) provided herein, or pharmaceutically acceptable salts thereof, may be administered to subjects in amounts depending on: for example, the target of administration (e.g., the desired degree of relief); the age, weight, sex, and health and physical condition of the subject to which the formulation is administered; the route of administration; and the nature of the disease, condition, illness, or its symptoms. The dosing regimen may also take into account the presence, nature, and extent of any adverse reactions associated with the administered formulation. Effective doses and dosing regimens can be readily determined by, for example, safety and dose escalation studies, in vivo studies (e.g., animal models), and other methods known to those skilled in the art.

[0042] VI. General Definition Unless otherwise stated, the following terms used in this specification and claims are defined for the purposes of this application and have the following meanings: Unless the context clearly specifies otherwise, the singular forms “a,” “an,” and “the,” as used herein and in the appended claims, include the plural referent. It should also be noted that claims can be drafted to exclude any optional elements. Therefore, this statement is intended as a prior basis for using such exclusive terms such as “solely,” “only,” etc., or using negative limiting conditions when reciting elements of a claim.

[0043] Where a numerical range is provided, it should be understood that every interval between the upper and lower limits of the range (accurate to one-tenth of the lower limit unit unless the context clearly specifies otherwise), as well as any other specified value or interval within the specified range, is covered by this invention. The upper and lower limits of these smaller ranges may be independently included within the smaller range and also covered by this invention, subject to any specific exclusions within the specified range. If the specified range includes one or both of the included limits, then the range excluding any or both of those included limits is also included in this invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0044] Unless otherwise stated, the following terms used in this specification and claims are defined for the purposes of this application and have the following meanings: The term "alkyl," alone or as part of another substituent, unless otherwise specified, refers to a saturated straight-chain or branched hydrocarbon group having the specified number of carbon atoms (i.e., C46, ​​C56, C66, C5 ... 1-8 (Indicates 1 to 8 carbons). Alkyl groups can include any number of carbons, such as C10. 1-2 C 1-3 C 1-4 C 1-5 C 1-6 C 1-7 C 1-8 C 1-9 C 1-10 C 2-3 C 2-4 C 2-5 C 2-6 C 3-4 C 3-5 C 3-6 C 4-5 C 4-6 and C 5-6 Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, sec-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, etc.

[0045] The term "alkylene" refers to a straight-chain or branched, saturated aliphatic group having a specified number of carbon atoms and being attached to at least two other groups, i.e., divalent hydrocarbon groups. The two parts attached to the alkylene group can be attached to the same or different atoms of the alkylene group. For example, a straight-chain alkylene group can be -(CH2). n - a divalent group, where n is 1, 2, 3, 4, 5, or 6. Representative alkylene groups include, but are not limited to, methylene, ethylene, propylene, isopropylene, butylene, isobutylene, sec-butylene, pentylene, and hexylene.

[0046] The term "alkoxy group" refers to an alkyl group having an oxygen atom attached to a junction: alkyl-O-. Like alkyl groups, alkoxy groups can have any suitable number of carbon atoms (e.g., C10, C20, C30, C40, C50, C60, C70, C80, C9 ... 1-6 Alkoxy groups can be straight-chain or branched. Examples of alkoxy groups include, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy, 2-butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentoxy, hexoxy, etc.

[0047] As used herein, the term "cyano" alone or as part of another substituent refers to the portion having the formula -CN (i.e., a carbon atom bonded to a nitrogen atom via a triple bond).

[0048] The term "cycloalkyl" refers to a saturated or partially unsaturated hydrocarbon ring with a specified number of ring atoms (e.g., C16, C26, C36, C46, ​​C56, C6 ... 3-6 Cycloalkyl groups. Cycloalkyl groups can include any number of carbons, for example, C10. 3-6 C 4-6 C 5-6 C 3-8 C 4-8 C 5-8 C 6-8 C 3-9 and C 3-10 Some unsaturated cycloalkyl groups have one or more double or triple bonds in the ring, but the cycloalkyl groups are not aromatic. Saturated monocyclic cycloalkyl rings include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl.

[0049] The term "cycloalkyloxy group" refers to a cycloalkyl group having an oxygen atom attached to an attachment point: cycloalkyl-O-. Cycloalkyl groups are as defined herein.

[0050] The term "spirocyclic" or "spirocyclic alkyl" refers to a saturated or partially unsaturated bicyclic ring having 6 to 12 ring atoms, wherein the two rings are linked by a single carbon atom (also called a spiro atom). Partially unsaturated spirocyclic alkyl groups have one or more double or triple bonds within the ring, but are not aromatic. Representative examples include, but are not limited to, spiro[3.3]heptane, spiro[4.4]nonane, spiro[3.4]octane, etc.

[0051] The term "bridged cycloalkyl" refers to a monocyclic 6- to 11-membered hydrocarbon group in which two non-adjacent ring atoms are bridged by (CH2). n A group is linked, where n is 1 to 3 (also referred to herein as a bridging group). Examples of bridged cycloalkyl groups include, but are not limited to, bicyclo[2.2.1]heptane and bicyclo[2.2.2]octane. For simplicity, the term is also intended to include bridged polycyclic hydrocarbon groups, such as adamantane.

[0052] The term "heterocyclic alkyl" refers to a saturated or partially unsaturated monocyclic ring having a specified number of ring vertices (e.g., a 3- to 7-membered ring) and having 1 to 5 heteroatoms selected from N, O, and S as ring vertices. A partially unsaturated heterocyclic alkyl group has one or more double or triple bonds within the ring, but the heterocyclic alkyl group is not aromatic. A heterocyclic alkyl group may include any number of ring atoms, such as 3 to 6, 4 to 6, 5 to 6, 3 to 7, 4 to 7, or 5 to 7 ring members. A heterocyclic alkyl group may contain any suitable number of heteroatoms, such as 1, 2, 3, or 4, or 1 to 2, 1 to 3, 1 to 4, 2 to 3, 2 to 4, or 3 to 4. Non-limiting examples of heterocyclic alkyl groups include pyrrolidine, imidazoline, pyrazolidine, butyrolactam, valproic acid, imidazolidinone, hydantoin, dioxolane, phthalimide, piperidine, 1,4-dioxane, morpholine, thiomorpholine, thiomorpholine-S-oxide, thiomorpholine-S,S-oxide, piperazine, pyran, pyridone, 3-pyrrolidine, thiopyran, pyranone, tetrahydrofuran, tetrahydrothiophene, quinine ring, etc. Heterocyclic alkyl groups can be attached to the remainder of the molecule via a ring carbon atom or a heteroatom.

[0053] The term "bicyclic heterocyclic alkyl" or "bicyclic heterocyclic group" refers to a saturated or partially unsaturated fused bicycle having a specified number of ring vertices (e.g., 6 to 12 membered rings) and having 1 to 5 heteroatoms selected from N, O, and S as ring vertices. A partially unsaturated bicyclic heterocyclic alkyl group has one or more double or triple bonds within the ring, but the bicyclic heterocyclic alkyl group is not aromatic. A bicyclic heterocyclic alkyl group may include any number of ring atoms, such as 6 to 8, 6 to 9, 6 to 10, 6 to 11, or 6 to 12 ring members. A heterocyclic alkyl group may contain any suitable number of heteroatoms, such as 1, 2, 3, or 4, or 1 to 2, 1 to 3, 1 to 4, 2 to 3, 2 to 4, or 3 to 4. Non-limiting examples of bicyclic heterocyclic alkyl groups include decahydro-1,5-naphthidine, octahydropyrrolo[1,2-a]pyrazine, etc.

[0054] The term "bridged heterocyclic group" or "bridged heterocyclic alkyl" refers to a heterocyclic alkyl ring (with 5 to 8 ring vertices) in which two non-adjacent ring atoms are connected by a (CRR'). n A bridging group is formed where n is 1 to 3 and each R is independently H or methyl (also referred to herein as a “bridging” group). The bridging heterocyclic group has 1 to 5 heteroatoms selected from N, O, and S as ring vertices. The heteroatom ring vertices can be in the heterocyclic alkyl ring portion or in the bridging group. When in the bridging group, the heteroatom replaces the CRR' group. Examples include, but are not limited to, 2-azabicyclo[2.2.2]octane, quinine ring, 7-oxabicyclo[2.2.1]heptane, etc.

[0055] The term "spiroheteroalkyl" or "spiroheteroalkyl" refers to a saturated or partially unsaturated bicyclic ring having 6 to 12 ring atoms, wherein the two rings are linked by a single carbon atom (also called a spiro atom). Spiroheteroalkyl groups have 1 to 5 heteroatoms selected from N, O, and S as ring apexes, and the nitrogen atom may optionally be quaternized. Partially unsaturated spiroheteroalkyl groups have one or more double or triple bonds within the ring, but the spiroheteroalkyl group is not aromatic. Representative examples include, but are not limited to, 4-oxaspiro[2.4]heptane, 2,6-diazaspiro[3.3]heptane, 2,6-diazaspiro[3.4]octane, 2-azaspiro[3.4]octane, 2-azaspiro[3.5]nonane, 2,7-diazaspiro[4.4]nonane, etc.

[0056] The term “halo” or “halogen” refers, alone or as part of another substituent, to a fluorine, chlorine, bromine, or iodine atom unless otherwise stated.

[0057] The term "haloalkyl" refers to an alkyl group as defined above, in which some or all of the hydrogen atoms are replaced by halogen atoms. Like alkyl groups, haloalkyl groups can have any suitable number of carbon atoms, for example, C0. 1-6 For example, the term "C" 1-4 "Halogenated alkyl" is intended to include trifluoromethyl, 2,2,2-trifluoroethyl, 4-chlorobutyl, 3-bromopropyl, etc.

[0058] The term "haloalkoxy" refers to an alkoxy group in which some or all of the hydrogen atoms are replaced by halogen atoms. Like alkyl groups, haloalkoxy groups can have any suitable number of carbon atoms, such as C0. 1-6 These alkoxy groups can be straight-chain or branched, and can be substituted with one, two, three, or more halogens. When all hydrogens are substituted with a halogen (e.g., fluorine), the compound is fully substituted (e.g., perfluorinated). Haloalkoxy groups include, but are not limited to, trifluoromethoxy, 2,2,2-trifluoroethoxy, perfluoroethoxy, etc.

[0059] The term "hydroxyalkyl" refers to an alkyl group in which one of the hydrogen atoms is replaced by a hydroxyl (-OH) group. Like alkyl groups, hydroxyalkyl groups can have any suitable number of carbon atoms, for example, C0. 1-6 It can be straight-chain or branched. Hydroxyalkyl groups include, for example, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 2-hydroxypropyl-2-yl, etc.

[0060] Unless otherwise stated, the term "aryl" refers to a polyunsaturated, typically aromatic hydrocarbon group, which can be monocyclic or polycyclic (up to three rings) that are fused together or covalently linked. Non-limiting examples of aryl groups include phenyl, naphthyl, and biphenyl.

[0061] The term "heteroaryl" refers to a 5- to 10-membered aromatic ring (or fused ring system) containing 1 to 5 heteroatoms selected from N, O, and S. A heteroaryl group may contain any number of ring atoms, such as 5 to 6, 5 to 8, 6 to 8, 6 to 9, 9 to 10, 9, or 10 ring members. A heteroaryl group may contain any suitable number of heteroatoms, such as 1, 2, 3, 4, or 5, or 1 to 2, 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, 2 to 5, 3 to 4, or 3 to 5. A heteroaryl group can be attached to the rest of the molecule via heteroatoms. Non-limiting examples of heteroaryl groups include pyridinyl, pyrazinyl, pyrazinyl, pyrimidinyl, triazinyl, quinolinyl, quinoxalinyl, quinazolinyl, cyclophosphinyl, phthalazinyl, benzotriazinyl, purineyl, benzimidazolyl, benzopyrazolyl, benzotriazolyl, benzoisoxazolyl, isobenzofuranyl, isoindolyl, indazinyl, benzotriazinyl, thienopyridinyl, thienopyrimidinyl, pyrazolopyrimidinyl, imidazopyridinyl, benzothiazolyl, benzofuranyl, benzothiaphenyl, indolyl, quinolinyl, isoquinolinyl, isothiazolyl, pyrazolyl, indazole, pteridinyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiadiazolyl, pyrroleyl, thiazolyl, furanyl, thiopheneyl, etc.

[0062] As used herein, the term “heteroatoms” is intended to include oxygen (O), nitrogen (N), and sulfur (S).

[0063] When necessary, any definition herein may be used in combination with any other definition to describe complex structural groups. By convention, the tail element of any such definition is the element attached to the parent part. For example, the complex group alkoxyalkyl indicates that the alkoxy group is attached to the parent molecule via an alkyl group.

[0064] The compounds of this invention may contain one or more chiral carbon atoms. Therefore, these compounds may exist as diastereomers, enantiomers, or mixtures thereof. The synthesis of these compounds may use racemic, diastereomer, or enantiomers as starting materials or intermediates. Mixtures of specific diastereomer compounds may be separated or enriched into one or more specific diastereomers by chromatography or crystallization. Similarly, mixtures of enantiomers may be separated or enantiomerically enriched using the same techniques or other techniques known in the art. Each of the asymmetric carbon or nitrogen atoms may be in an R or S configuration, and both configurations are within the scope of this invention.

[0065] In the structures shown herein, all stereoisomers are covered and included as compounds of the present invention unless the stereochemistry of any particular chiral atom is defined. A stereoisomer is defined and specified by a solid wedge or dashed line representing a particular configuration. Unless otherwise specified, the use of a solid wedge or dashed line indicates relative stereochemistry.

[0066] The term "stereoisomer" refers to compounds that have the same chemical composition but differ in the spatial arrangement of atoms or groups. Stereoisomers include diastereomers, enantiomers, transisomers, and conformational isomers.

[0067] The term "chirality" refers to a molecule that has the property of not being superimposed on its mirror image, while the term "achirality" refers to a molecule that is superimposed on its mirror image.

[0068] The term "diastereomer" refers to a stereoisomer that has two or more chiral centers and whose molecules are not mirror images of each other. Diastereomers possess different physical properties, such as melting point, boiling point, spectral properties, or biological activity. Mixtures of diastereomers can be separated using high-resolution analytical procedures such as electrophoresis and chromatographic methods like HPLC.

[0069] The term "enantiomer" refers to two stereoisomers of a compound that are non-superimposable mirror images of each other.

[0070] The stereochemical definitions and conventions used in this paper generally follow those of SP Parker, *McGraw-Hill Dictionary of Chemical Terms* (1984), McGraw-Hill Books, New York; and Eliel, E. and Wilen, S., “Stereochemistry of Organic Compounds”, John Wiley & Sons, New York, 1994. Many organic compounds exist in an optically active form, meaning they possess the ability to rotate the plane of polarized light. In describing optically active compounds, the prefixes D and L or R and S are used to indicate the absolute configuration of the molecule around its chiral center. The prefixes d and l or (+) and (-) are used to specify the sign of the rotation of the compound with respect to plane-polarized light, where (-) or l indicates that the compound is levorotatory. Compounds with the prefix (+) or d are dextrorotatory. For a given chemical structure, these stereoisomers are equivalent except that they are mirror images of each other. Specific stereoisomers can also be called enantiomers, and mixtures of such isomers are generally referred to as enantiomeric mixtures. A 50:50 mixture of enantiomers is called a racemic mixture or racemate, which may occur in chemical reactions or processes without stereoselectivity or stereospecificity. The terms "racemic mixture" and "racemate" refer to an equimolar mixture of two enantiomeric species that is not optically active.

[0071] The terms "tautomer" or "tautomer form" refer to structural isomers with different energies that can interconvert through low energy barriers. For example, proton tautomers (also known as proton-transformation tautomers) include interconversions via proton migration, such as keto-enol and imine-enamine isomerization. Valence tautomers include interconversions through partial recombination of bonding electrons.

[0072] As used herein, “pharmaceutically acceptable salt” is intended to include salts of active compounds prepared using relatively non-toxic acids or bases, depending on the specific substituents found on the compounds described herein. When the compounds disclosed herein contain relatively acidic functional groups, base adduct salts can be obtained by contacting the neutral form of these compounds with a sufficient amount of the desired base (whether pure or in a suitable inert solvent).

[0073] This disclosure also includes protected derivatives of the compounds disclosed herein. For example, when the compounds of this disclosure contain hydroxyl, carboxyl, mercapto, or any group containing a nitrogen atom, these groups may be protected with suitable protecting groups. A detailed list of suitable protecting groups can be found in TW Greene, whose disclosure is incorporated herein by reference in its entirety. Protected derivatives of the compounds of this disclosure may be prepared by methods well known in the art.

[0074] This disclosure also includes prodrugs of compounds of formula (I) (and any embodiments thereof disclosed herein, including specific compounds) or pharmaceutically acceptable salts thereof. Prodrugs of the compounds described herein refer to those compounds that readily undergo chemical changes under physiological conditions to provide the compounds of the present invention. A non-limiting example of a prodrug would be a compound administered as an ester (“prodrug”) which is subsequently metabolized and hydrolyzed to a carboxylic acid (i.e., the active entity). Additionally, prodrugs can be converted into the compounds of the present invention by chemical or biochemical methods in an in vitro environment. For example, when prodrugs are placed in a transdermal patch reservoir containing suitable enzymes or chemical reagents, they can be slowly converted into the compounds of the present invention.

[0075] Some compounds of formula (I) (and any embodiments thereof disclosed herein, including specific compounds) may be present in both unsolvable and solvable forms (including hydrated forms). Generally, solvable and unsolvable forms are equivalent and are intended to be covered by the scope of this invention. Some compounds of formula (I) may be present in polycrystalline or amorphous forms. Generally, all physical forms are equivalent for the uses covered by this disclosure and are intended to fall within the scope of this disclosure.

[0076] Certain compounds of formula (I) (and any embodiments thereof disclosed herein, including specific compounds) have asymmetric carbon atoms (optical centers) or double bonds; racemates, diastereomers, geometric isomers, regioisomers, and individual isomers (e.g., isolated enantiomers) are all intended to be covered within the scope of this invention. When a stereochemical description is shown, it means a compound in which one of the isomers is present and substantially free of the other isomer. “Substantially free of the other isomer” means a ratio of at least 80 / 20, more preferably 90 / 10, or 95 / 5 or higher of the two isomers. In some embodiments, one of the isomers is present in an amount of at least 99%.

[0077] Certain compounds disclosed herein may exist as tautomers and / or geometric isomers. All possible tautomers, as well as cis and trans isomers, as individual forms and mixtures thereof, are within the scope of this disclosure.

[0078] Compounds of Formula (I) (and any embodiments thereof disclosed herein, including specific compounds) may also contain non-natural amounts of isotopes at one or more positions of the atoms constituting such compounds. Non-natural amounts of isotopes can be defined as ranging from amounts found in nature to 100% of the atoms involved, distinguished only by the presence of one or more isotope-enriched atoms. Exemplary isotopes that can be introduced into compounds of the present invention (e.g., compounds of Formula (I) (and any embodiments thereof disclosed herein, including specific compounds)) include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine, chlorine, and iodine, for example, respectively. 2 H, 3 H, 11 C 13 C 14 C 13 N、 15 N、 15 O、 17 O、 18 O、 32 P, 33 P, 35 S, 18 F, 36 Cl、 123 I and 125 I. Isotope-labeled compounds (e.g., those labeled with...) 3 H and 14 Compounds of C can be used for the determination of the tissue distribution of compounds or substrates. Tritium (i.e., 3 H) and carbon-14 (i.e. 14 C) Isotopes are available because they are easy to prepare and detectable. Additionally, heavier isotopes such as deuterium (i.e., 2 H) substitution may provide certain therapeutic advantages due to greater metabolic stability (e.g., increased in vivo half-life or reduced dose requirement). In some embodiments, among the compounds disclosed herein, including those in Table 1 above, one or more hydrogen atoms in the compound are... 2 H or 3 H substitution, or one or more carbon atoms being replaced 13 C or 14 Carbon-enriched carbon substitution. Such as... 15 O、 13 N、 11 C and 18 Positron emission isotopes of F can be used in positron emission tomography (PET) studies to examine substrate acceptor occupancy. Typically, isotopically labeled compounds can be prepared by replacing non-isotopically labeled reagents with isotopically labeled reagents by following procedures similar to those disclosed in the reaction routes or examples herein.

[0079] "Pharmaceutically acceptable carrier or excipient" means a carrier or excipient that can be used to prepare a pharmaceutical composition, which is generally safe, non-toxic, and not undesirable in a biological or other respectable manner, and includes carriers or excipients acceptable for veterinary use as well as for human pharmaceutical use. As used in this specification and claims, "pharmaceuticalally acceptable carrier / excipient" includes one or more such excipients.

[0080] As used herein, “about” is intended to qualify the numerical value it modifies, indicating that the value may vary within a certain margin of error. When a specific margin of error is not specified (e.g., the standard deviation of the average given in a chart or table of data), the term “about” should be understood to refer to a range that would cover ±10% (preferably ±5%), including both the specified value and this range.

[0081] As used herein, “disease” is intended to be broadly synonymous with and interchangeable with the terms “symptom,” “syndrome,” and “condition,” all of which reflect an abnormal condition of a person or animal’s body or part thereof that impairs normal functioning, is usually manifested by characteristic signs and symptoms, and results in a reduced lifespan or quality of life for the person or animal.

[0082] The term “patient” is broadly synonymous with the term “subject” and, as used herein, includes all mammals, including humans. Examples of patients include humans, livestock (such as cattle, goats, sheep, pigs, and rabbits), and companion animals (such as dogs, cats, rabbits, and horses). Preferably, the patient is a human.

[0083] As used in this article, "requiring treatment" means that the patient is receiving treatment from a physician or other caregiver after a diagnosis of a disease. For example, the patient has been diagnosed with a disease associated with overexpression of Polθ or a homologous recombination (HR) defective cancer.

[0084] The terms “administration” and “administer,” when applied to, for example, a patient, cell, tissue, organ, or biological fluid, refer to the contact between a compound of formula (I), a pharmaceutical composition comprising it, or a diagnostic agent, and a subject, cell, tissue, organ, or biological fluid. In the context of cells, administration includes contact between the reagent and cells (e.g., in vitro or ex vivo contact) and contact between the reagent and a fluid, wherein the fluid contacts the cell.

[0085] As used herein, a “therapeutic effective amount” refers to an amount of a compound of formula (I) (and any embodiments thereof disclosed herein, including specific compounds) or a pharmaceutically acceptable salt thereof, which, when administered to a patient for the treatment of a disease, is sufficient to achieve such treatment of the disease, whether administered alone or as part of a pharmaceutical composition, and whether as a single dose or as part of a series of doses. The “therapeutic effective amount” can vary depending on the compound, the disease and its severity, and the age, weight, etc., of the mammal being treated. Therapeutic effective amounts can be determined by measuring relevant physiological effects and can be adjusted in conjunction with the dosing regimen and diagnostic analysis of the subject's condition. For example, the measurement of serum levels of a compound of formula (I) (or, for example, its metabolites) at a specific time after administration can indicate whether a therapeutically effective amount has been used.

[0086] The “treating” or “treatment” of a disease includes: (1) Suppress the disease, that is, prevent or reduce the development of the disease or its clinical symptoms; or (2) Relieve the disease, that is, cause the disease or its clinical symptoms to subside.

[0087] The terms “inhibition,” “reducing,” or any variation thereof used with respect to Polθ include any measurable decrease or complete inhibition to achieve the desired result. For example, a decrease in Polθ activity compared to its normal activity may be about, at most about, or at least about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, or any range thereof.

[0088] The term "prevention" refers to the prevention of the development of clinical symptoms of a disease in mammals that may be exposed to or susceptible to the disease but have not yet experienced or exhibited symptoms of the disease.

[0089] The term "homologous recombination" refers to the cellular process of gene recombination in which nucleotide sequences are exchanged between two similar or equivalent DNA sequences.

[0090] The term "homological recombination (HR) deficient cancer" refers to cancer characterized by a reduction or absence of functional HR repair pathways. HR deficiency may result from the deletion of one or more HR-related genes or the presence of one or more mutations in one or more HR-related genes. Examples of HR-related genes include BRCA1, BRCA2, RAD54, RAD51B, CtlP (choline transporter-like protein), PALB2 (BRCA2 chaperone and localizer), XRCC2 (X-ray repair 2, which supplements defect repair in Chinese hamster cells), RECQL4 (RecQ protein-like 4), BLM (Bloom syndrome, RecQ helicase-like), WRN (Warner syndrome, one or more HR-related genes), Nbs 1 (Nibrin protein), and genes encoding Fanconi anemia (FA) proteins or FA-like genes, such as FANCA, FANCB, FANCC, FANCD1 (BRCA2), FANCD2, FANCE, FANCF, FANCG, FANCI, FANJ (BRIP1), FANCL, FANCM, FANCN (RALB2), FANCP (SLX4), FANCS (BRCA1), RAD51C, and XPF.

[0091] The term "Polθ overexpression" refers to an increase in the expression or activity of Polθ in diseased cells (e.g., cancer cells) relative to the expression or activity in normal cells (e.g., non-pathological cells of the same type). The amount of Polθ relative to its expression in normal cells can be at least 2, 3, 4, 5, 10, or more. Examples of Polθ-related cancers include, but are not limited to, breast cancer, ovarian cancer, cervical cancer, lung cancer, colorectal cancer, stomach cancer, bladder cancer, and prostate cancer.

[0092] example The following embodiments and references (intermediates) are intended to provide a complete disclosure and description of how to make and use the invention for those skilled in the art, and are not intended to limit the scope of the inventors' view of their invention, nor to indicate that the following experiments were performed or that they are all possible experiments. It should be understood that the exemplary descriptions written in the present tense are not necessarily performed, but rather refer to those descriptions that can be performed to generate data, etc., of the properties described. Every effort has been made to ensure the accuracy of the figures used (e.g., quantities, temperatures, etc.), but some experimental errors and biases should be taken into account.

[0093] I. Compound Synthesis Intermediate A: 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid 2'-Chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid methyl ester A solution of methyl 4-bromo-6-methylpyridin-3-carboxylate (10.0 g, 43.46 mmol, 1.00 equivalent), (2-chloro-5-methoxypyridin-4-yl)boronic acid (8.94 g, 47.81 mmol, 1.10 equivalent), and Cs₂CO₃ (42.49 g, 130.40 mmol, 3.0 equivalent) in dioxane (200 mL) was stirred overnight at 80 °C under a nitrogen atmosphere. The resulting mixture was extracted with EtOAc (3 × 200 mL). The combined organic layers were washed with water (1 × 200 mL) and dried over anhydrous Na₂SO₄. The filtrate was concentrated under reduced pressure and purified by silica gel column chromatography, eluted with petroleum ether / ethyl acetate (1:1) to give methyl 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (5.0 g, 39.3% yield).

[0094] 2'-Chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid A solution of methyl 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (5 g, 17.08 mmol, 1.00 equivalent) and LiOH·H₂O (3.58 g, 85.40 mmol, 5 equivalent) in water (40 mL) and MeOH (8 mL) was stirred at room temperature for 2 h. The mixture was acidified to pH 5 with concentrated hydrochloric acid. The mixture was cooled to 0 °C. The precipitated solid was collected by filtration and washed with water (3 × 10⁻⁶ mL). The residue was purified by grinding with water (200 mL). The precipitated solid was collected by filtration and washed with water (3 × 10⁻⁶ mL). The resulting solid was dried under reduced pressure in an oven. This yielded 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (4.0 g, 84.0% yield).

[0095] Example 1: 2'-Chloro-5'-methoxy-N-{6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-12) 4-Chloro-2-[(4-methoxycyclohexyl)oxy]-5-nitropyridine Under a nitrogen atmosphere, diisopropyl azodicarbonate (8.69 g, 42.97 mmol, 1.50 equivalent) was added to a stirred solution of 4-chloro-5-nitropyridin-2-ol (5.00 g, 28.64 mmol, 1.00 equivalent) and 4-methoxycyclohexanol (5.59 g, 42.97 mmol, 1.50 equivalent) in THF (50 mL, 42.971 mmol) at 0 °C. The resulting mixture was stirred overnight at room temperature under nitrogen and concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (10:1) to give 4-chloro-2-[(4-methoxycyclohexyl)oxy]-5-nitropyridinium (4.00 g, 48.7% yield).

[0096] 4-Chloro-6-[(4-methoxycyclohexyl)oxy]pyridine-3-amine A solution of 4-chloro-2-[(4-methoxycyclohexyl)oxy]-5-nitropyridine (4.00 g, 13.95 mmol, 1.00 equivalent), Fe (3.89 g, 69.75 mmol, 5.00 equivalent), and NH4Cl (7.46 g, 139 mmol, 10.0 equivalent) in ethanol (50 mL) and water (10 mL) was stirred at 80 °C for 1 hour. The resulting mixture was filtered, and the filter cake was washed with ethanol (50 mL) (3 × 10 mL), followed by concentration under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure to give 4-chloro-6-[(4-methoxycyclohexyl)oxy]pyridine-3-amine (3.00 g, 84% yield).

[0097] 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridine-2-amine A solution of 4-chloro-6-[(4-methoxycyclohexyl)oxy]pyridine-3-amine (3.00 g, 11.68 mmol, 1.00 equivalent) and potassium thiocyanate (3.41 g, 35.055 mmol, 3.00 equivalent) in concentrated hydrochloric acid (1 mL) and dioxane (90 mL) was stirred overnight at 90 °C. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure to give 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridine-2-amine (500 mg, 15% yield).

[0098] 2'-Chloro-5'-methoxy-N-{6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide At 0 °C, a solution of 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridine-2-amine (120 mg, 0.43 mmol, 1.00 equivalent) in DMF (2 mL) was treated with HATU (245 mg, 0.64 mmol, 1.50 equivalent) for 10 min, followed by the addition of 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 143 mg, 0.51 mmol, 1.20 equivalent) and DIEA (166 mg, 1.29 mmol, 3.00 equivalent) at 0 °C. The resulting mixture was stirred overnight at room temperature. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure to give 2'-chloro-5'-methoxy-N-{6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (20.7 mg).

[0099] LC-MS (ES + m / z: 540.20 (M+H) + 1 1H NMR (400 MHz, DMSO-d6): δ12.97(s,1H), 8.85 (s, 1H), 8.61 (d, J =3.2 Hz, 1H), 8.16 (s, 1H), 7.57 (s, 1H), 7.46 (s, 1H), 7.37 (d, J = 6.9 Hz,1H), 5.15 – 4.91 (m, 1H), 3.61 (s, 3H), 3.24 (d, J = 3.1 Hz, 3H), 2.60 (s,3H), 2.01 (t, J = 17.1 Hz, 2H), 1.88 – 1.56 (m, 4H), 1.42 (dq, J = 52.7, 9.9Hz, 2H)]. Examples 2 and 3: 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1s,4s)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridin]-3-carboxamide (C-2) and 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridin]-3-carboxamide (C-1) 2'-chloro-5'-methoxy-N-{6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (Example 1, 50 mg) was purified by reversed-phase rapid chromatography using the following conditions: column, CHIRALPAK IH-3; mobile phase, MEOH (0.1% DEA), 10% to 50% in 3.0 min, held at 50% for 3.0 min. The resulting mixture was concentrated under reduced pressure. This yields 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1s,4s)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (14.1 mg, 28% yield) and 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (11.4 mg, 23% yield). The structures are arbitrary.

[0100] LC-MS (ES +m / z: 540.10 (M+H) + 1 1H NMR (400 MHz, DMSO-d6): [delta] (dt, J =9.2, 5.1 Hz, 1H), 3.60 (s, 3H), 3.25 (s, 4H), 2.60 (s, 3H), 2.14 – 1.85 (m,4H), 1.48 (q, J = 10.0 Hz, 2H), 1.35 (q, J = 9.9 Hz, 2H)]. LC-MS (ES + m / z: 540.15 (M+H) + 1 1H NMR (400 MHz, DMSO-d6): [delta] (dt, J =9.2, 5.1 Hz, 1H), 3.61 (s, 3H), 3.35 (m, 1H), 3.24 (s, 3H), 2.60 (s, 3H),1.64-1.8 (m, 8H). The following compounds were synthesized using the alcohols or monoprotected alcohols necessary in step 1, as described in Example 1.

[0101] Table 2

[0102] Example 15: 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-d]pyrimidin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-9) 3H-[1,3]thiazo[4,5-d]pyrimidine-2-thione Under a nitrogen atmosphere at 120 °C, a mixture of 5-chloropyrimidin-4-amine (5.00 g, 38.59 mmol, 1.00 equivalent) and potassium [(ethoxymethionyl)thio] (12.40 g, 77.35 mmol, 2.00 equivalent) in DMF (50 mL) was stirred overnight. The resulting mixture was used directly in the next step without further purification.

[0103] 2-(methylthio)-[1,3]thiazo[4,5-d]pyrimidine At 0 °C, CH3I (3.15 g, 22.161 mmol, 1.50 equivalent) was added dropwise to a stirred solution of 3H-[1,3]thiazo[4,5-d]pyrimidine-2-thione (2.5 g, 14.77 mmol, 1.00 equivalent) in DMF (50 mL). The resulting mixture was stirred at 0 °C for another 2 hours. The precipitated solid was collected by filtration and washed with ethyl acetate (3 × 5 mL). This yielded 2-(methylthio)-[1,3]thiazo[4,5-d]pyrimidine (2.00 g, 74% yield).

[0104] [1,3]thiazo[4,5-d]pyrimidin-2-amine A solution (7 M) (2 mL) of 2-(methylthio)-[1,3]thiazo[4,5-d]pyrimidine (500 mg, 2.72 mmol, 1.00 equivalent) and NH3 (g) in MeOH was stirred at 60 °C for 2 h under a nitrogen atmosphere. The resulting mixture was concentrated under reduced pressure. The crude product was used directly for the next step without further purification. This yielded [1,3]thiazo[4,5-d]pyrimidine-2-amine (200 mg, crude).

[0105] 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-d]pyrimidin-2-yl}-[4,4'-bipyridine]-3-carboxamide Under nitrogen atmosphere, DCC (118 mg, 0.57 mmol, 3.50 equivalent) and DMAP (70 mg, 0.57 mmol, 3.50 equivalent) were added to a mixture of [1,3]thiazo[4,5-d]pyrimidine-2-amine (25 mg, 0.16 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 50.36 mg, 0.18 mmol, 1.10 equivalent) in a stirred DCM (2 mL) at room temperature. The resulting mixture was stirred overnight at room temperature under nitrogen atmosphere. The resulting mixture was filtered, and the filter cake was washed with DCM (3 × 1 mL) and concentrated under reduced pressure. The crude product (15 mg) was purified by preparative-grade HPLC under the following conditions (column: Xselect CSH C18 OBD column, 30 × 150 mm, 5 μm; mobile phase A: water (0.1% FA), mobile phase B: acetonitrile; flow rate: 60 mL / min; gradient: 25% B to 45% B over 8 min; wavelength: 254 nm / 220 nm; RT1 (min): 7.2) to 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-d]pyrimidin-2-yl}-[4,4'-bipyridine]-3-carboxamide (4.8 mg, 7% yield).

[0106] LC-MS (ES + m / z: 410.95 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) d 13.62 (s, 1H), 9.22 (s, 1H), 8.98 (d, J =16.7 Hz, 2H), 8.15 (s, 1H), 7.54 (s, 1H), 7.40 (s, 1H), 3.60 (s, 3H), 2.59(s, 3H). Example 16: 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[5,4-d]pyrimidin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-8) N-{[1,3]thiazo[5,4-d]pyrimidin-2-yl}benzamide A solution of 4-chloropyrimidin-5-amine (2.00 g, 15.43 mmol, 1.00 equivalent) and benzoyl isothiocyanate (5.04 g, 30.87 mmol, 2.00 equivalent) in acetone (10 mL) was stirred overnight at 60 °C. The resulting mixture was concentrated under reduced pressure. The precipitated solid was collected by filtration and washed with hexane (3 × 10 mL). The resulting solid was dried in a vacuum oven. This yielded N-{[1,3]thiazo[5,4-d]pyrimidin-2-yl}benzamide (1.50 g, 38% yield).

[0107] [1,3]thiazo[5,4-d]pyrimidin-2-amine A solution of N-{[1,3]thiazo[5,4-d]pyrimidin-2-yl}benzamide (500 mg, 1.95 mmol, 1.00 equivalent) in 30% aqueous H₂SO₄ (5 mL) was stirred overnight at 100 °C. The mixture was alkalized to pH 8 with saturated aqueous NaHCO₃. The resulting mixture was extracted with CH₂Cl₂ (3 × 50 mL). The combined organic layers were washed with water (1 × 10 mL) and dried over anhydrous Na₂SO₄. After filtration, the filtrate was concentrated under reduced pressure. This yielded [1,3]thiazo[5,4-d]pyrimidin-2-amine (100 mg, 34% yield).

[0108] 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[5,4-d]pyrimidin-2-yl}-[4,4'-bipyridine]-3-carboxamide A solution of 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 50 mg, 0.17 mmol, 1.00 equivalent), [1,3]thiazo[5,4-d]pyrimidine-2-amine (100 mg, 0.65 mmol, 3.6 equivalent), TCFH (N,N,N',N'-tetramethylchloroformamidinium hexafluorophosphate, 76 mg, 0.62 mmol, 3.50 equivalent), and NMI (N-methylimidazole, 129 mg, 0.62 mmol, 3.50 equivalent) in DMF (1 mL) and MeCN (1 mL) was stirred overnight at room temperature. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[5,4-d]pyrimidin-2-yl}-[4,4'-bipyridine]-3-carboxamide (39.9 mg, 52% yield).

[0109] LC-MS (ES + m / z: 413.05 (M+H) + 1 1H NMR (300 MHz, DMSO-d6): [delta] (s, 3H),2.61 (s, 3H)]. Example 17: 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[5,4-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-15) 1-Benzoyl-3-(5-bromo-2-methoxypyridin-4-yl)thiourea A mixture of 4-amino-3-bromopyridine (5 g, 28.90 mmol, 1.00 equivalent) and benzoyl isothiocyanate (5.19 g, 31.79 mmol, 1.10 equivalent) in acetone (50 mL) was stirred overnight at 60 °C under a nitrogen atmosphere. The mixture was then cooled to room temperature. The precipitated solid was collected by filtration and washed with ethyl acetate (3 × 10 mL). The crude product was used directly for the next step without further purification. This yielded 3-benzoyl-1-(3-bromopyridin-4-yl)thiourea (1.56 g, 16% yield).

[0110] 3-Bromopyridin-4-ylthiourea A solution of 3-benzoyl-1-(3-bromopyridin-4-yl)thiourea (1.5 g, 4.46 mmol, 1.00 equivalent) and NaOH (15 mL, 6 M) in methanol (30 mL) was stirred at 70 °C for 2 h under a nitrogen atmosphere. The mixture was then cooled to room temperature. An aqueous solution of NH4Cl was added dropwise to the mixture at 0 °C over 5 minutes. The precipitated solid was collected by filtration and washed with water (3 × 5 mL). The crude product was used directly in the next step without further purification. This yielded 3-bromopyridin-4-ylthiourea (1.03 g, crude).

[0111] [1,3]thiazo[5,4-c]pyridine-2-amine Under a nitrogen atmosphere at room temperature, L-proline (0.99 g, 8.61 mmol, 2.00 equivalent) and Cs₂CO₃ (2.81 g, 8.616 mmol, 2.00 equivalent) were added to a mixture of 3-bromopyridin-4-ylthiourea (1.0 g, 4.30 mmol, 1.00 equivalent) and CuI (0.86 g, 4.523 mmol, 1.05 equivalent) in DMSO (10 mL) with stirring. The resulting mixture was stirred overnight at 70 °C under a nitrogen atmosphere. The mixture was cooled to room temperature and poured into water (10 mL). The precipitated solid was collected by filtration and further washed with water (3 × 5 mL). The crude product was used directly for the next step without further purification. This yielded [1,3]thiazo[5,4-c]pyridin-2-amine (137 mg, 21% yield).

[0112] 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[5,4-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, TCFH (74 mg, 0.26 mmol, 2.00 equivalent) and NMI (32 mg, 0.39 mmol, 3.00 equivalent) were added to a stirred solution of [1,3]thiazo[5,4-c]pyridine-2-amine (20 mg, 0.13 mmol, 1.20 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (44 mg, 0.15 mmol, 1.20 equivalent) in DMF (0.5 mL). The resulting mixture was stirred overnight at room temperature, and the crude product (30 mg) was purified by preparative-grade HPLC using the following conditions (column: XBridge Shield RP18 OBD column 30). 150 mm, 5 m; mobile phase A: water (10 mmol / L NH4HCO3 + 0.05% NH3·H2O), mobile phase B: ACN; flow rate: 50 mL / min; gradient: 10% B to 45% B over 10 min; wavelength: 254 nm / 220 nm; RT1(min): 6.436), yielding 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[5,4-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (5.1 mg, 10% yield).

[0113] LC-MS (ES + m / z: 411.90 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) d 13.30 (s, 1H), 9.12 (brs, 1H), 8.91 (s,1H), 8.51 (brs, 1H), 8.15 (s, 1H), 7.69 (brs, 1H), 7.56 (s, 1H), 7.43 (s,1H), 3.59 (s, 3H), 2.60 (s, 3H). Example 18: 2'-chloro-5'-methoxy-N-{6-methoxy-[1,3]thiazo[5,4-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-19) 1-Benzoyl-3-(5-bromo-2-methoxypyridin-4-yl)thiourea A mixture of 5-bromo-2-methoxypyridin-4-amine (5.0 g, 24.62 mmol, 1.00 equivalent) and benzoyl isothiocyanate (6.05 g, 37.07 mmol, 1.51 equivalent) in acetone (50 mL) was stirred at 70 °C for 3 hours under a nitrogen atmosphere. The mixture was cooled to room temperature, and the precipitated solid was collected by filtration and washed with acetone (2 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 1-benzoyl-3-(5-bromo-2-methoxypyridin-4-yl)thiourea (7.45 g, 83% yield).

[0114] 5-Bromo-2-methoxypyridin-4-ylthiourea A mixture of 1-benzoyl-3-(5-bromo-2-methoxypyridin-4-yl)thiourea (7.0 g, 19.11 mmol, 1.00 equivalent) and NaOH (15.93 mL, 1 M) in methanol (70 mL) was stirred at 70 °C for 2 hours under a nitrogen atmosphere. The resulting mixture was concentrated under reduced pressure. The reaction was quenched at 0 °C by adding 20 mL of saturated aqueous NH4Cl solution. The precipitated solid was collected by filtration and washed with water (2 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 5-bromo-2-methoxypyridin-4-ylthiourea (5.23 g, crude).

[0115] 6-Methoxy-[1,3]thiazo[5,4-c]pyridine-2-amine Under a nitrogen atmosphere at room temperature, Cs₂CO₃ (4.97 g, 15.26 mmol, 2.00 equivalent) and L-proline (1.76 g, 15.26 mmol, 2.00 equivalent) were added to a stirred mixture of 5-bromo-2-methoxypyridin-4-ylthiourea (2.0 g, 7.63 mmol, 1.00 equivalent) and CuI (1.53 g, 8.01 mmol, 1.05 equivalent) in DMSO (20 mL). The resulting mixture was stirred overnight at 70 °C under a nitrogen atmosphere. The mixture was cooled to room temperature and added to water (50 mL). The precipitated solid was collected by filtration and washed with water (3 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 6-methoxy-[1,3]thiazo[5,4-c]pyridin-2-amine (1.2 g, 87% yield).

[0116] 2'-Chloro-5'-methoxy-N-{6-methoxy-[1,3]thiazo[5,4-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, TCFH (154 mg, 0.55 mmol, 2.00 equivalent) and NMI (67 mg, 0.82 mmol, 3.00 equivalent) were added dropwise to a stirred solution of 6-methoxy-[1,3]thiazo[5,4-c]pyridine-2-amine (50 mg, 0.27 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 92 mg, 0.33 mmol, 1.20 equivalent) in DMF (1 mL). The resulting mixture was stirred at room temperature under a nitrogen atmosphere for 2 h. The crude product (30 mg) was purified by preparative-grade HPLC using the following conditions (column: XBridge preparative-grade Phenyl OBD column 30). 150 mm, 5 μm; mobile phase A: water (10 mmol / L NH4HCO3 + 0.05% NH3·H2O), mobile phase B: ACN; flow rate: 50 mL / min; gradient: 18% B to 43% B over 10 min; wavelength: 254 nm / 220 nm; RT1(min): 8.715), yielding 2'-chloro-5'-methoxy-N-{6-methoxy-[1,3]thiazo[5,4-c]pyridin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (17.6 mg, 14% yield).

[0117] LC-MS (ES + m / z: 442.15 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) d 13.22 (s, 1H), 8.88 (s, 1H), 8.72 (s, 1H),8.16 (s, 1H), 7.57 (s, 1H), 7.45 (s, 1H), 7.05 (s, 1H), 3.89 (s, 3H), 3.60(s, 3H), 2.60 (s, 3H). Example 19: 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-b]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-25) A solution of 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (50 mg, 0.17 mmol, 1.00 equivalent), [1,3]thiazo[4,5-b]pyridine-2-amine (commercially available, 32 mg, 0.21 mmol, 1.20 equivalent), DCC (129 mg, 0.62 mmol, 3.50 equivalent), and DMAP (76 mg, 0.62 mmol, 3.5 equivalent) in dichloromethane (2 mL) was stirred overnight at room temperature. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yields 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-b]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (26.9 mg, 36% yield).

[0118] LC-MS (ES + m / z: 412.00 (M+H) + 1 1H NMR (300 MHz, DMSO-d6): δ [13.24 (s, 1H), 8.90 (s, 1H), 8.55 (dd,J = 4.7, 1.7 Hz, 1H), 8.41 (d,J = 7.8 Hz, 1H), 8.16 (s, 1H), 7.58 (s, 1H),7.45 (s, 1H), 7.31 (dd, J = 7.8, 4.8 Hz, 1H), 3.61 (s, 3H), 2.61 (s, 3H)]. Example 20: 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-b]pyrazin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-27) N-[(pyrazin-2-yl)aminothiocarbonyl]ethyl carbamate A solution of 2-aminopyrazine (5.0 g, 52.57 mmol, 1.00 equivalent) in 1,4-dioxane (25 mL) was treated with ethoxycarbonyl isothiocyanate (7.58 g, 57.830 mmol, 1.100 equivalent) for 30 minutes at 5 °C under air atmosphere. The resulting mixture was stirred overnight at room temperature. The mixture was then concentrated under reduced pressure. The resulting residue (5 g, 42% yield) was used directly for the next step without further purification.

[0119] N-{[1,3]thiazo[4,5-b]pyrazin-2-yl}carbamate ethyl ester At room temperature, N-[(pyrazin-2-yl)aminothiocarbonyl]carbamate (4.0 g, 17.68 mmol, 1.00 equivalent), HCl (6M) (8.33 mL, 274.21 mmol, 15.51 equivalent), and dioxane (20 mL) were added to a 50 mL round-bottom flask. The resulting mixture was stirred at 50 °C for 4 hours and then cooled to room temperature. The precipitated solid was collected by filtration and washed with dioxane (3 × 5 mL). The crude product, N-{[1,3]thiazo[4,5-b]pyrazin-2-yl}carbamate (2.0 g, 51%), was used directly for the next step without further purification.

[0120] [1,3]Thiazo[4,5-b]pyrazin-2-amine At room temperature, N-{[1,3]thiazo[4,5-b]pyrazin-2-yl}carbamate (1.0 g, 4.46 mmol, 1.00 equivalent), NaOH (0.54 g, 13.38 mmol, 3.00 equivalent), and H2O (10 mL) were added to a round-bottom flask. The resulting mixture was stirred overnight at 100 °C. The mixture was acidified to pH 3 with concentrated hydrochloric acid. The precipitated solid was collected by filtration and washed with water (15 mL) (3 × 5 mL). The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm, to give [1,3]thiazo[4,5-b]pyrazin-2-amine (150 mg, 13.3% yield).

[0121] 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-b]pyrazin-2-yl}-[4,4'-bipyridine]-3-carboxamide At room temperature, 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 150 mg, 0.53 mmol, 1 equivalent), [1,3]thiazo[4,5-b]pyrazin-2-amine (150 mg, 0.59 mmol, 1.10 equivalent, 60.3%), DMAP (230 mg, 1.88 mmol, 3.50 equivalent), DCC (388 mg, 1.88 mmol, 3.50 equivalent), and CH2Cl2 (4 mL) were added to a round-bottom flask. The resulting mixture was stirred overnight at room temperature under air. The crude product was purified by preparative-grade HPLC under the following conditions (column, C18 silica gel; mobile phase, water containing acetonitrile (0.1% FA), 10% to 50% gradient over 10 min; detector, UV 254 nm) to give 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-b]pyrazin-2-yl}-[4,4'-bipyridine]-3-carboxamide (68.8 mg, 29% yield).

[0122] LC-MS (ES + m / z: 413.00 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) δ 13.50 (s, 1H), 8.91 (s, 1H), 8.63 (d, J =2.6 Hz, 1H), 8.49 (d, J = 2.6 Hz, 1H), 8.17 (s, 1H), 7.60 (s, 1H), 7.47 (s,1H), 3.63 (s, 3H), 2.61 (s, 3H). Example 21: 2'-Chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-b]pyridin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-34) 2-(2-Methoxyethoxy)-5-nitropyridine A solution of 2-chloro-5-nitropyridine (2.0 g, 12.61 mmol, 1.00 equivalent), 2-methoxyethanol (1.44 g, 18.92 mmol, 1.50 equivalent), and Cs₂CO₃ (12.33 g, 37.84 mmol, 3.00 equivalent) in DMF (50 mL) was stirred overnight at room temperature. The resulting mixture was extracted with EtOAc (3 × 50 mL). The combined organic layers were washed with water (3 × 10 mL) and dried over anhydrous Na₂SO₄. After filtration, the filtrate was concentrated under reduced pressure. This yielded 2-(2-methoxyethoxy)-5-nitropyridine (1.5 g, 60% yield).

[0123] 6-(2-Methoxyethoxy)pyridine-3-amine A solution of 2-(2-methoxyethoxy)-5-nitropyridine (1.5 g, 7.56 mmol, 1.00 equivalent), Fe (2.11 g, 37.84 mmol, 5 equivalent), and NH4Cl (4.05 g, 75.69 mmol, 10.0 equivalent) in ethanol (50 mL) and water (10 mL) was stirred at 80 °C for 1 hour. The resulting mixture was filtered, and the filter cake was washed with ethanol (3 × 10 mL). The filtrate was concentrated under reduced pressure to give 6-(2-methoxyethoxy)pyridine-3-amine (1.0 g, 79% yield).

[0124] 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-b]pyridine-2-amine A solution of 6-(2-methoxyethoxy)pyridine-3-amine (1.0 g, 5.94 mmol, 1.00 equivalent), potassium thiocyanate (3.47 g, 35.67 mmol, 6.00 equivalent), and Br2 (1.01 g, 6.30 mmol, 1.06 equivalent) in acetic acid (20 mL) was stirred overnight at room temperature. The mixture was alkalized to pH 8 with a saturated aqueous solution of NaHCO3. The resulting mixture was extracted with CH2Cl2 (3 × 50 mL). The combined organic layers were washed with water (1 × 10 mL) and dried over anhydrous Na2SO4. After filtration, the filtrate was concentrated under reduced pressure. This yielded 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-b]pyridine-2-amine (600 mg, 45% yield).

[0125] 2'-Chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-b]pyridin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-b]pyridine-2-amine (100 mg, 0.44 mmol, 1.00 equivalent), 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (148.46 mg, 0.533 mmol, 1.20 equivalent), TCFH (435 mg, 1.55 mmol, 3.50 equivalent), and NMI (127 mg, 1.55 mmol, 3.50 equivalent) in DMF (1.5 mL) and MeCN (1.5 mL) was stirred overnight at room temperature. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded 2'-chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-b]pyridin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (9.9 mg, 4% yield).

[0126] LC-MS (ES + m / z: 486.10 (M+H) + 1 1H NMR (400 MHz, DMSO-d6): δ [12.89 (s, 1H), 8.83 (s, 1H), 8.17 (s,1H), 8.07 (d, J = 8.8 Hz, 1H), 7.57 (s, 1H), 7.46 (s, 1H), 6.94 (d, J = 8.8Hz, 1H), 4.47 – 4.38 (m, 2H), 3.72 – 3.65 (m, 2H), 3.61 (s, 3H), 3.31 (s, 3H), 2.60 (s, 3H), 1.24 (s, 2H)]. Example 22: 2'-Chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-35) Ethyl N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate Under a nitrogen atmosphere at room temperature, ethyl ethoxycarbonyl isothiocyanate (8.00 g, 60.98 mmol, 2.00 equivalent) was added to a stirred solution of 2,4-dichloropyrimidin-5-amine (5.00 g, 30.50 mmol, 1.00 equivalent) in methanol (150 mL). The resulting mixture was stirred at 60 °C for 30 min. The precipitated solid was collected by filtration and washed with methanol (3 × 15 mL). This yielded ethyl N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (5.00 g, 63% yield).

[0127] N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate ethyl ester Under a nitrogen atmosphere at 0°C, NaH (0.56 g, 23.19 mmol, 2.00 equivalent) was added dropwise to a stirred solution of 2-methoxyethanol (1.06 g, 13.92 mmol, 1.20 equivalent) in DMF (30 mL). The resulting mixture was stirred at 0°C under a nitrogen atmosphere for 30 minutes. N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (3.00 g, 11.60 mmol, 1.00 equivalent) was added to the mixture at 0°C, and the mixture was stirred at 100°C for another 3 hours. The reaction was quenched with water and extracted with ethyl acetate (3 × 50 mL). The combined organic layers were washed with NaCl (3 × 20 mL), dried over anhydrous Na₂SO₄, and concentrated under reduced pressure. The crude product was purified by reversed-phase rapid chromatography under the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19...). 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 61% B, 61% B over 7 min; wavelength: 254 / 220 nm; RT1(min): 6.28), yielding N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate (800 mg, 23% yield).

[0128] 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine A solution of N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate (300 mg, 1.00 mmol, 1.00 equivalent) and NaOMe (543.28 mg, 10.06 mmol, 10.00 equivalent) in MeOH (10 mL) was stirred at 60 °C for 5 hours under nitrogen atmosphere and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19...). 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 41% B, 41% B over 7 min; wavelength: 254 / 220 nm; RT1(min): 6.28), yielding 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (120 mg, 53% yield).

[0129] 2'-Chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere, DCC (159 mg, 0.77 mmol, 3.50 equivalent) and DMAP (94 mg, 0.77 mmol, 3.50 equivalent) were added to a stirred solution of 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (50 mg, 0.22 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 73 mg, 0.27 mmol, 1.20 equivalent) in DMF (1 mL). The resulting mixture was stirred overnight at room temperature and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions (column: XSelect CSH preparative grade C18OBD column, 19...). 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 31% B, 31% B over 7 min; wavelength: 254 / 220 nm; RT1 (min): 6.28), yielding 2'-chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (2.5 mg, 2% yield).

[0130] LC-MS (ES + m / z: 487.05 (M+H) + 1 H NMR (400 MHz, DMSO-d6): [δ 13.18 (s, 1H), 8.90 (s, 2H), 8.16 (s,1H), 7.47 (d, J = 52.2 Hz, 2H), 4.64 – 4.42 (m, 2H), 3.80 – 3.66 (m, 2H), 3.62 (s, 3H), 3.31 (s, 3H), 2.59 (s, 3H) ]. Example 23: 2'-Chloro-5'-methoxy-N-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-36) 1-{6-bromo-[1,3]thiazo[4,5-b]pyrazin-2-yl}-2,5-dimethylpyrrole A solution of 6-bromo-[1,3]thiazo[4,5-b]pyrazin-2-amine (3.5 g, 15.14 mmol, 1.00 equivalent), 2,5-hexanedione (2.07 g, 18.17 mmol, 1.20 equivalent), and TsOH·H₂O (0.29 g, 1.51 mmol, 0.1 equivalent) in toluene (50 mL) was stirred overnight at 110 °C. The resulting mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (5:1), to give 1-{6-bromo-[1,3]thiazo[4,5-b]pyrazin-2-yl}-2,5-dimethylpyrrole (2.0 g, 43% yield).

[0131] 1-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-yl]-2,5-dimethylpyrrole A solution of 1-{6-bromo-[1,3]thiazo[4,5-b]pyrazin-2-yl}-2,5-dimethylpyrrole (2 g, 6.46 mmol, 1.00 equivalent), 2-methoxyethanol (0.59 g, 7.76 mmol, 1.20 equivalent), and Na₂CO₃ (2.06 g, 19.40 mmol, 3.00 equivalent) in DMF (50 mL) was stirred at 110 °C for 3 days. The resulting mixture was filtered, and the filter cake was washed with acetonitrile (3 × 10 mL) and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH₄HCO₃), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yields 1-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-yl]-2,5-dimethylpyrrole (250 mg, 13% yield).

[0132] 6-(2-Methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-amine A solution of 1-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-yl]-2,5-dimethylpyrrole (250 mg, 0.82 mmol, 1.00 equivalent) in water (2 mL) was treated with TFA (2 mL) at 0 °C for 3 h and stirred at 60 °C for 3 h. The resulting mixture was concentrated under reduced pressure. The mixture was alkalized to pH 8 using DIEA. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded 6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-amine (80 mg, 43% yield).

[0133] 2'-Chloro-5'-methoxy-N-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of 6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-amine (40 mg, 0.17 mmol, 1.00 equivalent), 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (59.13 mg, 0.212 mmol, 1.2 equivalent), TCFH (75 mg, 0.61 mmol, 3.50 equivalent), and NMI (127 mg, 0.619 mmol, 3.50 equivalent) in DMF (1 mL) and ACN (1 mL) was stirred overnight at room temperature. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded 2'-chloro-5'-methoxy-N-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyrazin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (52 mg, 59% yield).

[0134] LC-MS (ES + m / z: 487.05 (M+H) + 1 1 H NMR (400 MHz, DMSO-d6): δ [13.23 (s, 1H), 8.86 (s, 1H), 8.32 (s,1H), 8.17 (s, 1H), 7.59 (s, 1H), 7.47 (s, 1H), 4.60 – 4.35 (m, 2H), 3.76 –3.67 (m, 2H), 3.62 (s, 3H), 3.31 (s, 3H), 2.61 (s, 3H). Example 24: 2'-Chloro-N-[6-(3-hydroxypropyl)-[1,3]thiazo[4,5-c]pyridin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-41) 2-{3-[(tert-butyldimethylsilyl)oxy]prop-1-yn-1-yl}-4-chloro-5-nitropyridine Under a nitrogen atmosphere at room temperature, Pd(PPh3)2Cl2 (0.89 g, 1.26 mmol, 0.10 equivalent), CuI (0.24 g, 1.26 mmol, 0.1 equivalent), and TEA (2.56 g, 25.27 mmol, 2.00 equivalent) were added to a stirred solution of 2-bromo-4-chloro-5-nitropyridine (3.00 g, 12.64 mmol, 1.00 equivalent) and tert-butyldimethyl(prop-2-yn-1-yloxy)silane (2.58 g, 15.16 mmol, 1.20 equivalent) in DMF (30 mL). The resulting mixture was stirred for 5 hours under a nitrogen atmosphere at room temperature. The reaction was monitored by LCMS. The reaction was quenched by adding water (30 mL) at room temperature. The resulting mixture was extracted with EtOAc (3 × 30 mL). The combined organic layers were washed with NaCl (3 × 30 mL) and dried over anhydrous Na₂SO₄. After filtration, the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (10:1) to give 2-{3-[(tert-butyldimethylsilyl)oxy]prop-1-yn-1-yl}-4-chloro-5-nitropyridine (2.10 g, 50.85% yield).

[0135] 6-{3-[(tert-butyldimethylsilyl)oxy]prop-1-yn-1-yl}-4-chloropyridine-3-amine Fe (1.79 g, 32.13 mmol, 5.00 equivalent) was added to a solution of 2-{3-[(tert-butyldimethylsilyl)oxy]prop-1-yn-1-yl}-4-chloro-5-nitropyridine (2.10 g, 6.43 mmol, 1.00 equivalent) and NH4Cl (3.44 g, 64.25 mmol, 10.00 equivalent) in EtOH (25 mL) and H2O (5 mL) under a nitrogen atmosphere at room temperature. The resulting mixture was stirred at 80 °C for 2 hours, filtered, and the filter cake was washed with EtOH (25 mL). The filtrate was concentrated under reduced pressure and purified by silica gel column chromatography, eluted with petroleum ether / ethyl acetate (5:1) to give 6-{3-[(tert-butyldimethylsilyl)oxy]prop-1-yn-1-yl}-4-chloropyridin-3-amine (1.70 g, 93% yield).

[0136] 6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-4-chloropyridine-3-amine A solution of 6-{3-[(tert-butyldimethylsilyl)oxy]propyl-1-yn-1-yl}-4-chloropyridin-3-amine (1.70 g, 5.73 mmol, 1.00 equivalent) and PtO2 (0.13 g, 0.57 mmol, 0.10 equivalent) in methanol (20 mL) was stirred at room temperature under a hydrogen atmosphere for 5 hours. The resulting mixture was filtered, and the filter cake was washed with MeOH (20 mL). The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (5:1) to give 6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-4-chloropyridin-3-amine (700 mg, 41% yield).

[0137] 3-{2-amino-[1,3]thiazo[4,5-c]pyridin-6-yl}prop-1-ol A solution of 6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-4-chloropyridin-3-amine (700 mg, 2.33 mmol, 1.00 equivalent) and KSCN (452 ​​mg, 4.65 mmol, 2.00 equivalent) in HCl (1 M) (5 mL) was stirred overnight at 90 °C under a nitrogen atmosphere. The resulting mixture was cooled and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19...). 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 41% B, 41% B over 7 min; wavelength: 254 / 220 nm; RT1 (min): 6.28) to give 3-{2-amino-[1,3]thiazo[4,5-c]pyridin-6-yl}prop-1-ol (300 mg, 61.6% yield).

[0138] 6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-[1,3]thiazo[4,5-c]pyridine-2-amine Under a nitrogen atmosphere at room temperature, TBSCl (259.28 mg, 1.72 mmol, 1.20 equivalent) was added to a stirred solution of 3-{2-amino-[1,3]thiazo[4,5-c]pyridin-6-yl}prop-1-ol (300 mg, 1.43 mmol, 1.00 equivalent) and imidazole (195.2 mg, 2.86 mmol, 2.00 equivalent) in DCM (5 mL). The resulting mixture was stirred overnight under a nitrogen atmosphere at room temperature and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19...). 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 41% B, 41% B over 7 min; wavelength: 254 / 220 nm; RT1 (min): 6.28) to give 6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-[1,3]thiazo[4,5-c]pyridine-2-amine (75 mg, 16% yield).

[0139] N-(6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-[1,3]thiazo[4,5-c]pyridin-2-yl)-2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, DCC (156.25 mg, 0.76 mmol, 3.50 equivalents) and DMAP (92.52 mg, 0.76 mmol, 3.50 equivalents) were added to a stirred solution of 6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-[1,3]thiazo[4,5-c]pyridine-2-amine (70 mg, 0.22 mmol, 1.00 equivalents) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 72.36 mg, 0.26 mmol, 1.20 equivalents) in DCM (2 mL, 31.46 mmol, 145.4 equivalents). The resulting mixture was stirred overnight at room temperature and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19...). 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 41% B, 41% B over 7 min; wavelength: 254 / 220 nm; RT1 (min): 6.28) yielded N-(6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-[1,3]thiazo[4,5-c]pyridin-2-yl)-2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (70 mg, 55% yield).

[0140] 2'-Chloro-N-[6-(3-hydroxypropyl)-[1,3]thiazo[4,5-c]pyridin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of N-(6-{3-[(tert-butyldimethylsilyl)oxy]propyl}-[1,3]thiazo[4,5-c]pyridin-2-yl)-2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (70 mg, 0.12 mmol, 1.00 equivalent) and NH4F (22 mg, 0.60 mmol, 5.00 equivalent) in methanol (2 mL) was stirred overnight at 60 °C under nitrogen atmosphere, and the resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19...). 150 mm, 5 μm; Mobile phase A: water (0.05% NH4HCO3), Mobile phase B: acetonitrile; Flow rate: 25 mL / min; Gradient: 10% B to 41% B, 41% B over 7 min; Wavelength: 254 / 220 nm; RT1 (min): 6.28) to give 2'-chloro-N-[6-(3-hydroxypropyl)-[1,3]thiazo[4,5-c]pyridin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (46.3 mg, 82.23% yield).

[0141] LC-MS (ES + m / z: 470.05 (M+H) + 1H NMR (300 MHz, DMSO-d6): δ 13.12 (s, 1H), 8.90 (d, J = 14.8 Hz,2H), 8.16 (s, 1H), 7.88 (s, 1H), 7.59 (s, 1H), 7.46 (s, 1H), 4.52 (s, 1H), 3.60 (s, 3H), 3.45 (t, J = 6.6 Hz, 2H), 2.85 (t, J = 7.7 Hz, 2H), 2.61 (s, 3H), 1.86 (p, J = 6.9 Hz, 2H). Example 25: 2'-Chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-b]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (C-20) 3-Bromo-5-[(4-methoxycyclohexyl)oxy]-2-nitropyridine Sodium hydride (1.36 g, 33.94 mmol, 1.80 equivalent, 60% in oil) was added to a solution of 4-methoxycyclohexanol (2.45 g, 18.85 mmol, 1.00 equivalent) in DMF (50 mL) at 0 °C. The mixture was stirred for 15 min. 3-Bromo-5-fluoro-2-nitropyridine (5 g, 22.626 mmol, 1.20 equivalent) was added, and the mixture was heated to room temperature and stirred for 2 h. The reaction mixture was quenched with water and extracted with ethyl acetate (3 × 25 mL). The resulting mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (1 / 1) to give 3-bromo-5-[(4-methoxycyclohexyl)oxy]-2-nitropyridine (3 g, 48% yield).

[0142] 3-Bromo-5-[(4-methoxycyclohexyl)oxy]pyridine-2-amine Iron powder (2.53 g, 45.29 mmol, 5.00 equivalent) was added in portions to a stirred mixture of 3-bromo-5-[(4-methoxycyclohexyl)oxy]-2-nitropyridine (3 g, 9.05 mmol, 1.00 equivalent) and NH4Cl (4.85 g, 90.59 mmol, 10.00 equivalent) in EtOH (30 mL) and H2O (3 mL) at room temperature under a nitrogen atmosphere. The resulting mixture was stirred overnight at 80 °C, cooled, filtered, and the filter cake was washed with water (3 × 10 mL). The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (0.1% formic acid (FA)), 10% to 100% gradient over 20 min; detector, UV 254 nm. This yields 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridine-2-amine (2.4 g, 87.96% yield).

[0143] 1-Benzoyl-3-{3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-yl}thiourea A solution of 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-amine (2.4 g, 7.96 mmol, 1.00 equivalent) and benzoyl isothiocyanate (1.95 g, 11.95 mmol, 1.50 equivalent) in acetone (25 mL) was stirred at 60 °C for 2 hours under a nitrogen atmosphere. The mixture was cooled to room temperature, and the precipitated solid was collected by filtration and washed with acetone (2 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 1-benzoyl-3-{3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-yl}thiourea (1.92 g, 52% yield).

[0144] 3-Bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-ylthiourea A mixture of 1-benzoyl-3-{3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-yl}thiourea (1.8 g, 3.87 mmol, 1.00 equivalent) and NaOH (3.6 mL, 6 M) in MeOH (20 mL) was stirred at 70 °C for 2 h under a nitrogen atmosphere, cooled, and quenched at 0 °C by adding 20 mL of saturated NH4Cl aqueous solution. The precipitated solid was collected by filtration and washed with water (3 × 4 mL). This yielded 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-ylthiourea (1.1 g, 79% yield).

[0145] 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-b]pyridine-2-amine Under a nitrogen atmosphere at room temperature, Cs₂CO₃ (904 mg, 2.77 mmol, 2.00 equivalent) and L-proline (319 mg, 2.77 mmol, 2.00 equivalent) were added to a stirred mixture of 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-ylthiourea (500 mg, 1.38 mmol, 1.00 equivalent) and CuI (277 mg, 1.45 mmol, 1.05 equivalent) in DMSO (5 mL). The resulting mixture was stirred overnight at 70 °C and poured into water. The precipitated solid was collected by filtration and washed with water (3 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-b]pyridin-2-amine (212 mg, 55% yield).

[0146] 2'-Chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-b]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, TCFH (200.87 mg, 0.716 mmol, 2.00 equivalent) and NMI (88.17 mg, 1.074 mmol, 3.00 equivalent) were added dropwise to a stirred solution of 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-b]pyridine-2-amine (100 mg, 0.358 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 119.71 mg, 0.430 mmol, 1.20 equivalent) in DMF (1 mL) and ACN (1 mL). The resulting mixture was stirred overnight under a nitrogen atmosphere at room temperature. The crude product (70 mg) was purified by preparative HPLC using the following conditions (column: CHIRALPAK-IK, 3). 25 mm, 5 μm; Mobile phase A: hexane (0.1% FA) -- HPLC, Mobile phase B: EtOH -- HPLC; Flow rate: 40 mL / min; Gradient: isocratic elution 50%; Wavelength: 220 / 200 nm; RT1 (min): 15.018; RT2 (min): 19.996; Sample solvent: MeOH: DCM = 1: 1 -- HPLC; Injection volume: 1 mL), yielding 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-b]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (17 mg, 8.8% yield).

[0147] LC-MS (ES + m / z: 540.25 (M+H) + 1 1 H NMR (400 MHz, methanol-) d 4) d 8.82 (s, 1H), 8.23 ​​(s, 1H), 8.06 (s, 1H), 8.01 (d, J = 2.6 Hz, 1H), 7.52 (s, 1H), 7.45 (s, 1H), 4.56 – 4.43 (m, 1H), 3.69 (s, 3H), 3.35 (s, 4H), 2.68 (s, 3H), 1.99 – 1.88 (m, 2H), 1.86 – 1.70 (m,6H), 1.29 (d, J = 4.4 Hz, 1H). Example 26: 2'-chloro-5'-methoxy-6-methyl-N-(6-{methyl[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (C-29) N2-Methyl-5-nitro-N2-[(1r,4r)-4-methoxycyclohexyl]pyridine-2,4-diamine Under a nitrogen atmosphere at room temperature, K₂CO₃ (10.51 g, 76.053 mmol, 3.00 equivalent) was added to a stirred mixture of 2-chloro-5-nitropyridine-4-amine (4.4 g, 25.35 mmol, 1.00 equivalent) and trans-4-methoxy-N-methylcyclohexane-1-amine (7.26 g, 50.702 mmol, 2.00 equivalent) in DMF (50 mL). The resulting mixture was stirred at 100 °C for 2 hours and extracted with ethyl acetate (3 × 100 mL). The combined organic layers were washed with water (3 × 10 mL), dried over anhydrous Na₂SO₄, and the filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 100% gradient over 20 min; detector, UV 254 nm. This yielded N2-methyl-5-nitro-N2-[(1r,4r)-4-methoxycyclohexyl]pyridine-2,4-diamine (4.58 g, 65% yield).

[0148] 4-Chloro-N-methyl-5-nitro-N-[(1r,4r)-4-methoxycyclohexyl]pyridine-2-amine Under a nitrogen atmosphere at 0 °C, CuCl2 (4.32 g, 32.13 mmol, 2.00 equivalent) was added to a stirred solution of N2-methyl-5-nitro-N2-[(1r,4r)-4-methoxycyclohexyl]pyridine-2,4-diamine (4.5 g, 16.05 mmol, 1.00 equivalent) and NaNO2 (2.78 g, 40.39 mmol, 2.52 equivalent) in HCl (6 M) (45 mL). The resulting mixture was stirred for 1 hour at room temperature and quenched by adding water (50 mL). The resulting mixture was extracted with EtOAc (3 × 100 mL). The combined organic layers were washed with water (3 × 3 mL) and dried over anhydrous Na2SO4. After filtration, the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography and eluted with petroleum ether / ethyl acetate (1 / 1) to give 4-chloro-N-methyl-5-nitro-N-[(1r,4r)-4-methoxycyclohexyl]pyridine-2-amine (411 mg, 8.5% yield).

[0149] 4-Chloro-N2-methyl-N2-[(1r,4r)-4-methoxycyclohexyl]pyridine-2,5-diamine Fe (383 mg, 6.85 mmol, 5.00 equivalent) was added dropwise to a mixture of 4-chloro-N-methyl-5-nitro-N-[(1r,4r)-4-methoxycyclohexyl]pyridine-2-amine (411 mg, 1.37 mmol, 1.00 equivalent) and NH4Cl (738 mg, 13.79 mmol, 10 equivalent) in EtOH (10 mL) and H2O (2 mL) under a nitrogen atmosphere at room temperature. The resulting mixture was stirred overnight at 80 °C and cooled to room temperature. The resulting mixture was filtered and the filter cake was washed with water (3 × 10 mL). The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 100% gradient over 10 min; detector, UV 254 nm. This yields 4-chloro-N2-methyl-N2-[(1r,4r)-4-methoxycyclohexyl]pyridine-2,5-diamine (100 mg, 27% yield).

[0150] N6-Methyl-N6-[(1r,4r)-4-methoxycyclohexyl]-[1,3]thiazo[4,5-c]pyridine-2,6-diamine Under a nitrogen atmosphere at room temperature, HCl (1 N, 0.4 mL) was added dropwise to a stirred solution of 4-chloro-N2-methyl-N2-[(1r,4r)-4-methoxycyclohexyl]pyridine-2,5-diamine (100 mg, 0.37 mmol, 1.00 equivalent) and potassium thiocyanate (108 mg, 1.11 mmol, 3.00 equivalent) in 2 mL of 1,4-dioxane. The resulting mixture was stirred overnight at 90 °C and neutralized to pH 7 using a saturated aqueous solution of NaHCO3. The residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields N6-methyl-N6-[(1r,4r)-4-methoxycyclohexyl]-[1,3]thiazo[4,5-c]pyridine-2,6-diamine (27 mg, 25% yield).

[0151] 2'-Chloro-5'-methoxy-6-methyl-N-(6-{methyl[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, DCC (61.74 mg, 0.298 mmol, 3.50 equivalent) and DMAP (36.56 mg, 0.298 mmol, 3.50 equivalent) were added to a stirred mixture of N6-methyl-N6-[(1r,4r)-4-methoxycyclohexyl]-[1,3]thiazo[4,5-c]pyridine-2,6-diamine (25 mg, 0.085 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 28.59 mg, 0.10 mmol, 1.20 equivalent) in DCM (2 mL). The resulting mixture was concentrated under reduced pressure. The crude product (30 mg) was purified by preparative-grade HPLC under the following conditions (column: XBridge preparative-grade Phenyl OBD column 30 × 150 mm, 5 μm; mobile phase A: water (10 mmol / L NH4HCO3), mobile phase B: methanol; flow rate: 60 mL / min; gradient: 55% B to 84% B over 8 min; wavelength: 254 nm / 220 nm; RT1 (min): 9.1) to give 2'-chloro-5'-methoxy-6-methyl-N-(6-{methyl[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (14.4 mg, 31% yield).

[0152] LC-MS (ES + m / z: 553.15 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) d 12.76 (s, 1H), 8.83 (s, 1H), 8.57 (s, 1H),8.16 (s, 1H), 7.56 (s, 1H), 7.45 (s, 1H), 7.13 (s, 1H), 4.49 (s, 1H), 3.61(s, 3H), δ 3.25 (s, 3H).3.19 – 3.07 (m, 1H), 2.83 (s, 3H), 2.60 (s, 3H), 2.08(d, J = 11.8 Hz, 2H), 1.62 (d, J = 8.6 Hz, 4H), 1.31 – 1.22 (m, 2H). Example 27: 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-c]pyridazin-6-yl}-[4,4'-bipyridine]-3-carboxamide (C-26) 3-Chloro-[1,3]thiazo[4,5-c]pyridazine-6-amine A solution of 4-bromo-6-chloropyridazine-3-amine (10 g, 47.97 mmol, 1.00 equivalent), potassium thiocyanate (6.99 g, 71.96 mmol, 1.50 equivalent), and Br2 (8.43 g, 52.77 mmol, 1.10 equivalent) in acetic acid (100 mL) was stirred overnight at 70 °C. The mixture was alkalized to pH 8 using a saturated aqueous solution of NaHCO3. The resulting mixture was extracted with EtOAc (3 × 100 mL). The combined organic layers were washed with water (1 × 10 mL) and dried over anhydrous Na2SO4. The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yields 3-chloro-[1,3]thiazo[4,5-c]pyridazine-6-amine (500 mg, 6% yield).

[0153] [1,3]Thiazo[4,5-C]pyridazine-6-amine A solution of 3-chloro-[1,3]thiazo[4,5-c]pyridazin-6-amine (500 mg, 2.67 mmol, 1.00 equivalent) and Pd / C (50 mg, 10% w / w) in methanol (5 mL) was stirred overnight at room temperature under a hydrogen atmosphere. The resulting mixture was filtered, and the filter cake was washed with methanol (5 mL) (3 × 10 mL) and concentrated under reduced pressure. This yielded [1,3]thiazo[4,5-c]pyridazin-6-amine (100 mg, 25% yield).

[0154] 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-c]pyridazin-6-yl}-[4,4'-bipyridine]-3-carboxamide A solution of [1,3]thiazo[4,5-c]pyridazine-6-amine (20 mg, 0.13 mmol, 1.00 equivalent), 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 43 mg, 0.15 mmol, 1.20 equivalent), DMAP (48 mg, 0.39 mmol, 3.00 equivalent), and DCC (81.35 mg, 0.393 mmol, 3 equivalent) in DCM (2 mL) was stirred overnight at room temperature. The resulting mixture was concentrated under reduced pressure and purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-c]pyridazin-6-yl}-[4,4'-bipyridine]-3-carboxamide (3.4 mg, 5.8% yield). LC-MS (ES) + m / z: 413.10 (M+H) + 1 1H NMR (400 MHz, DMSO-d6): δ [9.06 (s, 1H), 8.78 (d, J = 5.1 Hz, 1H), 8.12 (s, 1H), 7.99 (d, J = 5.1 Hz, 1H), 7.42 (s, 1H), 7.26 (s, 1H), 3.61 (s,3H), 2.57 (s, 3H)]. Example 28: 2'-Chloro-5'-methoxy-N-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyridin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-33) 3-Bromo-5-(2-Methoxyethoxy)-2-nitropyridine Sodium hydride (1.36 g, 33.93 mmol, 1.50 equivalent, 60% in oil) was added to a solution of 2-methoxyethanol (2.07 g, 27.15 mmol, 1.20 equivalent) in THF (50 mL) at 0 °C. The mixture was stirred for 30 min. 3-Bromo-5-fluoro-2-nitropyridine (5 g, 22.62 mmol, 1.00 equivalent) was added, and the mixture was heated to room temperature and stirred for 2 h. The reaction mixture was quenched with water and extracted with EA (3 × 25 mL). The resulting mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (3 / 1) to give 3-bromo-5-(2-methoxyethoxy)-2-nitropyridine (4.65 g, 74% yield).

[0155] 3-Bromo-5-(2-methoxyethoxy)pyridine-2-amine Fe (4.64 g, 83.01 mmol, 5.00 equivalent) was added to a mixture of 3-bromo-5-(2-methoxyethoxy)-2-nitropyridine (4.6 g, 16.60 mmol, 1.00 equivalent) and NH4Cl (8.88 g, 166.020 mmol, 10.00 equivalent) in EtOH (50 mL) and H2O (5 mL) under a nitrogen atmosphere at room temperature. The resulting mixture was stirred at 100 °C for 2 h under a nitrogen atmosphere, filtered, and the filter cake was washed with ethanol (3 × 10 mL). The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile, 10% to 100% gradient over 15 minutes; detector, UV 254 nm. This yields 3-bromo-5-(2-methoxyethoxy)pyridine-2-amine (4.0 g, 98% yield).

[0156] 1-Benzoyl-3-[3-bromo-5-(2-methoxyethoxy)pyridin-2-yl]thiourea A solution of 3-bromo-5-(2-methoxyethoxy)pyridin-2-amine (4.0 g, 16.18 mmol, 1.00 equivalent) and benzoyl isothiocyanate (3.96 g, 24.28 mmol, 1.50 equivalent) in acetone (40 mL) was stirred overnight at 70 °C under a nitrogen atmosphere. The mixture was cooled to room temperature and concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (2 / 1) to give 1-benzoyl-3-[3-bromo-5-(2-methoxyethoxy)pyridin-2-yl]thiourea (3.0 g, 45% yield).

[0157] 3-Bromo-5-(2-methoxyethoxy)pyridin-2-ylthiourea A solution of 1-benzoyl-3-[3-bromo-5-(2-methoxyethoxy)pyridin-2-yl]thiourea (2.0 g, 4.87 mmol, 1.00 equivalent) and NaOH (1 M aqueous solution, 4 mL) in MeOH (20 mL) was stirred at 70 °C for 2 hours under a nitrogen atmosphere. The mixture was cooled to room temperature. The resulting mixture was concentrated under reduced pressure, and the residue was washed with a saturated ammonium chloride solution (3 × 10 mL). The precipitated solid was collected by filtration and washed with water (3 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 3-bromo-5-(2-methoxyethoxy)pyridin-2-ylthiourea (1.7 g, crude).

[0158] 6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyridine-2-amine Under a nitrogen atmosphere at room temperature, Cs₂CO₃ (1064 mg, 3.26 mmol, 2.00 equivalent) and L-proline (377 mg, 3.27 mmol, 2.01 equivalent) were added to a stirred mixture of 3-bromo-5-(2-methoxyethoxy)pyridin-2-ylthiourea (500 mg, 1.63 mmol, 1.00 equivalent) and CuI (328 mg, 1.72 mmol, 1.05 equivalent) in DMSO (5 mL). The resulting mixture was stirred overnight at 70 °C and then cooled to room temperature. The reaction mixture was poured into water, and the precipitated solid was collected by filtration and washed with water (3 × 3 mL). The crude product was used directly for the next step without further purification. This yielded 6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyridin-2-amine (62 mg, 17% yield).

[0159] 2'-Chloro-5'-methoxy-N-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyridin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-33) Under a nitrogen atmosphere at room temperature, DCC (192 mg, 0.93 mmol, 3.50 equivalent) and DMAP (113 mg, 0.93 mmol, 3.50 equivalent) were added to a mixture of 6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyridine-2-amine (60 mg, 0.26 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (89 mg, 0.31 mmol, 1.20 equivalent) in a stirred DCM (2 mL). The resulting mixture was stirred overnight under a nitrogen atmosphere at room temperature and concentrated under reduced pressure. The crude product (40 mg) was purified by preparative-grade HPLC using the following conditions (column: XBridge Shield RP18 OBD column 30). 150 mm, 5 m; mobile phase A: water (10 mmol / L NH4HCO3), mobile phase B: ACN; flow rate: 60 mL / min; gradient: 15% B to 48% B over 8 min; wavelength: 254 nm / 220 nm; RT1(min): 9.33), yielding 2'-chloro-5'-methoxy-N-[6-(2-methoxyethoxy)-[1,3]thiazo[4,5-b]pyridin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (37.9 mg, 29% yield).

[0160] LC-MS (ES + m / z: 486.10 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) d 13.08 (s, 1H), 8.85 (s, 1H), 8.30 (d, J = 2.8Hz, 1H), 8.17 (s, 1H), 8.11 (d, J = 2.9 Hz, 1H), 7.59 (s, 1H), 7.46 (s, 1H), 4.27 – 4.17 (m, 2H), 3.73 – 3.66 (m, 2H), 3.61 (s, 3H), 3.3 (s, 3H), 2.61 (s, 3H). Example 29: 2'-Chloro-N-[6-(dimethylamino)-[1,3]thiazo[4,5-c]pyridin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-40) 4-Chloro-N,N-Dimethyl-5-nitropyridine-2-amine At 0 °C, sodium hydride (1.01 g, 49.5 mmol, 2.2 equivalents, 60% in oil) was added to a solution of 4-chloro-5-nitropyridine-2-amine (2.0 g, 11.5 mmol, 1.00 equivalent) in THF. The mixture was stirred for 15 min. CH3I (4.91 g, 34.56 mmol, 3 equivalents) was added, and the mixture was heated to room temperature and stirred for 2 h. The reaction mixture was quenched with water and extracted with DCM (3 × 25 mL). The combined organic layers were washed with water (1 × 10 mL), dried over anhydrous Na2SO4, and the filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yields 4-chloro-N,N-dimethyl-5-nitropyridine-2-amine (1.2 g, 52% yield).

[0161] 4-Chloro-N2,N2-dimethylpyridine-2,5-diamine A solution of 4-chloro-N,N-dimethyl-5-nitropyridine-2-amine (1.2 g, 5.95 mmol, 1.00 equivalent) in ethanol (20 mL) and water (4 mL) was treated with Fe (1.66 g, 29.7 mmol, 5.00 equivalent) and NH4Cl (3.18 g, 59.5 mmol, 10 equivalent) at room temperature. The resulting mixture was stirred at 80 °C for 2 h. The mixture was then concentrated under reduced pressure. The residue was dissolved in acetonitrile (20 mL). The resulting mixture was filtered, and the filter cake was washed with acetonitrile (3 × 5 mL). The filtrate was concentrated under reduced pressure. The crude product was used directly in the next step without further purification.

[0162] N6,N6-Dimethyl-[1,3]thiazo[4,5-c]pyridine-2,6-diamine At room temperature, potassium thiocyanate (1.36 g, 14.0 mmol, 3.00 equivalent) and HCl (0.28 mL) were added fractionally to a stirred solution of 4-chloro-N2,N2-dimethylpyridine-2,5-diamine (800 mg, 4.66 mmol, 1.00 equivalent) in dioxane (2 mL). The resulting mixture was stirred overnight at 90 °C and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded N6,N6-dimethyl-[1,3]thiazo[4,5-c]pyridine-2,6-diamine (300 mg, 33% yield).

[0163] 2'-Chloro-N-[6-(dimethylamino)-[1,3]thiazo[4,5-c]pyridin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide At room temperature, DCC (378 mg, 1.80 mmol, 3.50 equivalent) and DMAP (220 mg, 1.80 mmol, 3.50 equivalent) were added in portions to a stirred solution of N6,N6-dimethyl-[1,3]thiazo[4,5-c]pyridine-2,6-diamine (100 mg, 0.515 mmol, 1 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 143 mg, 0.51 mmol, 1.00 equivalent) in DCM (2 mL). The resulting mixture was stirred for 2 hours, the reaction mixture was concentrated, and the residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yielded 2'-chloro-N-[6-(dimethylamino)-[1,3]thiazo[4,5-c]pyridin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (23.1 mg, 9.7% yield).

[0164] LC-MS (ES + m / z: 455.1 (M+H) + 1H NMR (400 MHz, DMSO-d6) δ 12.79 (s, 1H), 8.83 (s, 1H), 8.60 – 8.55(m, 1H), 8.17 (s, 1H), 7.57 (s, 1H), 7.45 (s, 1H), 7.18 – 7.14 (m, 1H), 3.62(s, 3H), 3.05 (s, 6H), 2.60 (s, 3H). Example 30: 2'-chloro-5'-methoxy-6-methyl-N-[6-(methylamino)-[1,3]thiazo[4,5-c]pyridin-2-yl]-[4,4'-bipyridine]-3-carboxamide (C-39) N-(4-chloro-5-nitropyridin-2-yl)acetamide At room temperature, pyridine (2.73 g, 34.6 mmol, 2.00 equivalent) was added dropwise to a stirred solution of 4-chloro-5-nitropyridin-2-amine (3.00 g, 17.3 mmol, 1.00 equivalent) and acetyl chloride (2.04 g, 25.9 mmol, 1.50 equivalent) in dichloromethane (30 mL). The resulting mixture was stirred for 3 hours and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yielded N-(4-chloro-5-nitropyridin-2-yl)acetamide (2.00 g, 54% yield).

[0165] N-(4-chloro-5-nitropyridin-2-yl)-N-methylacetamide At 0 °C, sodium hydride (0.56 g, 2.50 equivalent, 60% in oil) was added to a solution of N-(4-chloro-5-nitropyridin-2-yl)acetamide (2.00 g, 9.23 mmol, 1.00 equivalent) in DMF (20 mL). The mixture was stirred for 15 min. CH3I (1.58 g, 11.1 mmol, 1.20 equivalent) was added, and the mixture was heated to room temperature and stirred for 2 h. The reaction mixture was quenched by adding water and extracted with DCM (3 × 25 mL). The combined organic layers were washed with water (1 × 10 mL) and dried over anhydrous Na2SO4. The filtrate was concentrated under reduced pressure, and the residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded N-(4-chloro-5-nitropyridin-2-yl)-N-methylacetamide (1.50 g, 70% yield).

[0166] N-(5-amino-4-chloropyridin-2-yl)-N-methylacetamide Iron powder (1.82 g, 32.6 mmol, 5.00 equivalent) and NH4Cl (3.49 g, 65.3 mmol, 10.0 equivalent) were added fractionally to a stirred solution / mixture of N-(4-chloro-5-nitropyridin-2-yl)-N-methylacetamide (1.50 g, 6.53 mmol, 1.00 equivalent) in ethanol (15 mL) and water (3 mL) at room temperature. The resulting mixture was stirred at 80 °C for 2 h, filtered, and the filter cake was washed with ethanol (3 × 10 mL). The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (5:1) to give N-(5-amino-4-chloropyridin-2-yl)-N-methylacetamide (1.00 g, 76.6% yield).

[0167] N-{2-amino-[1,3]thiazo[4,5-c]pyridin-6-yl}-N-methylacetamide At room temperature, concentrated hydrochloric acid (0.35 mL, 11.5 mmol, 2.30 equivalent) was added dropwise to a stirred solution of N-(5-amino-4-chloropyridin-2-yl)-N-methylacetamide (1.00 g, 5.00 mmol, 1.00 equivalent) and potassium thiocyanate (1.46 g, 15.0 mmol, 3.00 equivalent) in dioxane (30 mL). The resulting mixture was stirred overnight at 110 °C, concentrated under reduced pressure, and alkalized to pH 8 using DIEA. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yields N-{2-amino-[1,3]thiazo[4,5-c]pyridin-6-yl}-N-methylacetamide (400 mg, 36% yield).

[0168] 2'-Chloro-5'-methoxy-6-methyl-N-[6-(N-methylacetamido)-[1,3]thiazo[4,5-c]pyridin-2-yl]-[4,4'-bipyridine]-3-carboxamide At room temperature, DCC (487 mg, 2.36 mmol, 3.50 equivalent) and DMAP (288 mg, 2.36 mmol, 3.50 equivalent) were added fractionally to a stirred solution of N-{2-amino-[1,3]thiazo[4,5-c]pyridin-6-yl}-N-methylacetamide (150 mg, 0.675 mmol, 1 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (188 mg, 0.675 mmol, 1 equivalent) in a DCM (3 mL) container. The resulting mixture was stirred at room temperature for 2 hours and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yielded 2'-chloro-5'-methoxy-6-methyl-N-[6-(N-methylacetamido)-[1,3]thiazo[4,5-c]pyridin-2-yl]-[4,4'-bipyridine]-3-carboxamide (80 mg, 25% yield).

[0169] 2'-Chloro-5'-methoxy-6-methyl-N-[6-(methylamino)-[1,3]thiazo[4,5-c]pyridin-2-yl]-[4,4'-bipyridine]-3-carboxamide 2'-Chloro-5'-methoxy-6-methyl-N-[6-(N-methylacetamido)-[1,3]thiazo[4,5-c]pyridin-2-yl]-[4,4'-bipyridine]-3-carboxamide (80 mg, 0.166 mmol, 1.00 equivalent) and concentrated hydrochloric acid (0.8 mL) were added to an 8 mL vial at room temperature. The resulting mixture was stirred at 110 °C for 2 hours, cooled, and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yields 2'-chloro-5'-methoxy-6-methyl-N-[6-(methylamino)-[1,3]thiazo[4,5-c]pyridin-2-yl]-[4,4'-bipyridine]-3-carboxamide (25 mg, 35% yield).

[0170] LC-MS (ES + m / z: 441.0(M+H) + 1 H NMR (400 MHz, DMSO-d6) δ 12.74 (s, 1H), 8.83 (s, 1H), 8.47 (s,1H), 8.17 (s, 1H), 7.55 (s, 1H), 7.44 (s, 1H), 6.89 (s, 1H), 6.41 (d, J = 5.7Hz, 1H), 3.62 (s, 3H), 2.78 (d, J = 4.9 Hz, 3H), 2.59 (s, 3H)). Example 31: 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1s,4s)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-b]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (C-28) 3-Bromo-5-[(4-methoxycyclohexyl)oxy]-2-nitropyridine Sodium hydride (1.36 g, 33.94 mmol, 1.80 equivalent, 60% in oil) was added to a solution of 4-methoxycyclohexanol (2.45 g, 18.85 mmol, 1.00 equivalent) in DMF (50 mL) at 0 °C. The mixture was stirred for 15 min, and 3-bromo-5-fluoro-2-nitropyridine (5 g, 22.62 mmol, 1.20 equivalent) was added. The mixture was then heated to room temperature and stirred for 2 h. The reaction mixture was quenched with water and extracted with ethyl acetate (3 × 25 mL), and concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (1 / 1) to give 3-bromo-5-[(4-methoxycyclohexyl)oxy]-2-nitropyridine (3 g, 48% yield).

[0171] 3-Bromo-5-[(4-methoxycyclohexyl)oxy]pyridine-2-amine Iron powder (2.53 g, 45.29 mmol, 5.00 equivalent) was added in portions to a stirred mixture of 3-bromo-5-[(4-methoxycyclohexyl)oxy]-2-nitropyridine (3 g, 9.05 mmol, 1.00 equivalent) and NH4Cl (4.85 g, 90.59 mmol, 10.00 equivalent) in EtOH (30 mL) and H2O (3 mL) at room temperature under a nitrogen atmosphere. The resulting mixture was stirred overnight at 80 °C under a nitrogen atmosphere, cooled to room temperature, and filtered. The filter cake was then washed with water (30 mL) (3 × 10 mL). The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (0.1% FA), 10% to 100% gradient over 20 min; detector, UV 254 nm. This yields 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridine-2-amine (2.4 g, 88% yield).

[0172] 1-Benzoyl-3-{3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-yl}thiourea A solution of 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-amine (2.4 g, 7.96 mmol, 1.00 equivalent) and benzoyl isothiocyanate (1.95 g, 11.95 mmol, 1.50 equivalent) in acetone (25 mL) was stirred at 60 °C for 2 h under a nitrogen atmosphere. The mixture was cooled to room temperature. The precipitated solid was collected by filtration and washed with acetone (10 mL) (2 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 1-benzoyl-3-{3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-yl}thiourea (1.92 g, 52% yield).

[0173] 3-Bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-ylthiourea A mixture of 1-benzoyl-3-{3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-yl}thiourea (1.8 g, 3.87 mmol, 1.00 equivalent) and NaOH (3.6 mL, 6 M) in MeOH (20 mL) was stirred at 70 °C for 2 h under a nitrogen atmosphere. The mixture was cooled to room temperature and quenched at 0 °C by adding 20 mL of saturated NH4Cl aqueous solution. The precipitated solid was collected by filtration and washed with water (3 × 4 mL). This yielded 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-ylthiourea (1.1 g, 79% yield).

[0174] 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-b]pyridine-2-amine Under a nitrogen atmosphere at room temperature, Cs₂CO₃ (904 mg, 2.77 mmol, 2.00 equivalent) and L-proline (319 mg, 2.77 mmol, 2.00 equivalent) were added to a stirred mixture of 3-bromo-5-[(4-methoxycyclohexyl)oxy]pyridin-2-ylthiourea (500 mg, 1.38 mmol, 1.00 equivalent) and CuI (277 mg, 1.45 mmol, 1.05 equivalent) in DMSO (5 mL). The resulting mixture was stirred overnight at 70 °C, cooled, and poured into water. The precipitated solid was collected by filtration and washed with water (3 × 5 mL). The crude product was used directly for the next step without further purification. This yielded 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-b]pyridin-2-amine (212 mg, 55% yield).

[0175] 2'-Chloro-5'-methoxy-6-methyl-N-(6-{[(1s,4s)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-b]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, TCFH (200 mg, 0.35 mmol, 1.00 equivalence) and NMI (88 mg, 1.07 mmol, 3.00 equivalence) were added to a stirred solution of 6-[(4-methoxycyclohexyl)oxy]-[1,3]thiazo[4,5-b]pyridine-2-amine (100 mg, 0.35 mmol, 1.00 equivalence) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 119 mg, 0.43 mmol, 1.20 equivalence) in DMF (1 mL) and MeCN (1 mL). The resulting mixture was stirred overnight under a nitrogen atmosphere at room temperature. The crude product (70 mg) was purified by preparative-grade HPLC using the following conditions (column: CHIRALPAK-IK, 3). 25 mm, 5 μm; Mobile phase A: hexane (0.1% FA)--HPLC, Mobile phase B: EtOH--HPLC; Flow rate: 40 mL / min; Gradient: isocratic elution 50%; Wavelength: 220 / 200 nm; RT1 (min): 15.018; RT2 (min): 19.996), yielding 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1s,4s)-4-methoxycyclohexyl]oxy}-[1,3]thiazo[4,5-b]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (34.6 mg, 17.9% yield).

[0176] LC-MS (ES+) m / z: 540.20 (M+H) +1 1 H NMR (400 MHz, methanol-) d 4) d 8.82 (d, J = 2.1 Hz, 1H), 8.22 (s, 1H), 8.06(d, J = 1.9 Hz, 1H), 8.02 (t, J = 3.0 Hz, 1H), 7.52 (d, J = 2.1 Hz, 1H), 7.45 (d, J=1.5 Hz, 1H), 4.45 (d, J = 8.2 Hz, 1H), 3.69 (s, 3H), 3.35 (s, 4H), 2.68 (s, 3H), 2.16 – 2.02 (m, 4H), 1.65 – 1.44 (m, 4H). Example 32: 2'-Chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (C-14) 6-Chloro-[1,3]thiazo[4,5-c]pyridine-2-amine Under a nitrogen atmosphere at room temperature, potassium thiocyanate (44.8 g, 460.5 mmol, 3.00 equivalent) was added to a mixture of 4,6-dichloropyridin-3-amine (20.0 g, 122.69 mmol, 1.00 equivalent) and HCl (1.75 mL) in dioxane (500 mL) under stirring. The resulting mixture was stirred overnight at 110 °C under a nitrogen atmosphere. The mixture was cooled to room temperature, and the precipitated solid was collected by filtration and washed with ethyl acetate (3 × 20 mL). The crude product was used directly for the next step without further purification. This yielded 6-chloro-[1,3]thiazo[4,5-c]pyridin-2-amine (10 g, crude).

[0177] N-(6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl)carbamate tert-butyl ester Under a nitrogen atmosphere at room temperature, DMAP (0.66 g, 5.38 mmol, 0.10 equivalent) was added to a mixture of 6-chloro-[1,3]thiazo[4,5-c]pyridin-2-amine (10.0 g, 53.87 mmol, 1.00 equivalent) and (Boc)₂O (23.51 g, 107.74 mmol, 2.00 equivalent) in a stirred DCM (500 mL). The resulting mixture was stirred overnight under a nitrogen atmosphere at room temperature and concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (1 / 1) to give N-{6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl} tert-butyl carbamate (6 g, 39% yield).

[0178] N-{6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl}-N-[(4-methoxyphenyl)methyl]tert-butyl carbamate At 0 °C, sodium hydride (840 mg, 21.0 mmol, 2.00 equivalent, 60% in oil) was added to a solution of N-{6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl}carbamate (3.0 g, 10.49 mmol, 1.00 equivalent) in DMF (600 mL). The reaction mixture was stirred for 30 minutes, and PMB-Cl (1.97 g, 12.599 mmol, 1.20 equivalent) was added. The mixture was then heated to room temperature and stirred overnight. The reaction mixture was quenched with water and extracted with EA (3 × 50 mL). The resulting mixture was concentrated under reduced pressure and purified by silica gel column chromatography, eluted with petroleum ether / ethyl acetate (1 / 1) to give N-{6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl}-N-[(4-methoxyphenyl)methyl]carbamate tert-butyl ester (2.0 g, 47% yield).

[0179] N-[(4-methoxyphenyl)methyl]-N-(6-{[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)tert-butyl carbamate Under a nitrogen atmosphere at room temperature, Pd(OAc)2 (110 mg, 0.49 mmol, 0.10 equivalence), Xantphos (570 mg, 0.98 mmol, 0.20 equivalence), and Cs2CO3 (4816 mg, 14.78 mmol, 3.00 equivalence) were added dropwise to a stirred mixture of N-{6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl}-N-[(4-methoxyphenyl)methyl]carbamate (2.0 g, 4.92 mmol, 1.00 equivalence) and (1r,4r)-4-methoxycyclohexane-1-amine (763 mg, 5.91 mmol, 1.20 equivalence) in dioxane (20 mL) (110 mg, 0.49 mmol, 0.10 equivalence), Cs2CO3 (4816 mg, 14.78 mmol, 3.00 equivalence) were added dropwise. The resulting mixture was stirred overnight at 100°C under a nitrogen atmosphere, cooled to room temperature, and quenched with water (20 mL). The resulting mixture was extracted with EtOAc (3 × 50 mL). The combined organic layers were washed with brine (3 × 10 mL), dried over anhydrous Na₂SO₄, and concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile, 10% to 100% gradient over 10 minutes; detector, UV 254 nm. This yielded N-[(4-methoxyphenyl)methyl]-N-(6-{[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)tert-butyl carbamate (100 mg, 4.0% yield).

[0180] N6-[(1r,4r)-4-methoxycyclohexyl]-[1,3]thiazo[4,5-c]pyridine-2,6-diamine A solution of N-[(4-methoxyphenyl)methyl]-N-(6-{[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)carbamate tert-butyl ester (100 mg, 0.20 mmol, 1.00 equivalent) in TFA (10 mL) was stirred overnight at 75 °C. The resulting mixture was concentrated under reduced pressure, and the residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile, 10% to 100% gradient over 10 minutes; detector, UV 254 nm. This yielded N6-[(1r,4r)-4-methoxycyclohexyl]-[1,3]thiazo[4,5-c]pyridin-2,6-diamine (50 mg, 90% yield).

[0181] 2'-Chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, DCC (129.71 mg, 0.630 mmol, 3.50 equivalent) and DMAP (76.8 mg, 0.63 mmol, 3.50 equivalent) were added dropwise to a mixture of N6-[(1r,4r)-4-methoxycyclohexyl]-[1,3]thiazo[4,5-c]pyridine-2,6-diamine (50 mg, 0.18 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (60 mg, 0.21 mmol, 1.20 equivalent) in a stirred DCM (2 mL). The resulting mixture was stirred overnight under a nitrogen atmosphere at room temperature. The mixture was filtered, and the filter cake was washed with dichloromethane (3 × 3 mL). The filtrate was concentrated under reduced pressure. The crude product (50 mg) was purified by preparative HPLC under the following conditions (column: XBridgeShield RP18 OBD column 30). 150 mm, 5 m; mobile phase A: water (10 mmol / L NH4HCO3 + 0.1% NH3·H2O), mobile phase B: MeCN; flow rate: 60 mL / min; gradient: 30% B to 52% B over 8 min; wavelength: 254 nm / 220 nm; RT1(min): 7.5), yielding 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1r,4r)-4-methoxycyclohexyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (23.7 mg, 24.5% yield, 99.0% yield).

[0182] LC-MS (ES+) m / z: 539.15 (M+H) +1 1 H NMR (400 MHz, DMSO- d 6) d 12.73 (s, 1H), 8.82 (s, 1H), 8.45 (s, 1H), 8.16 (s, 1H), 7.55 (s, 1H), 7.44 (s, 1H), 6.90 (s, 1H), 6.30 (d, J= 7.8 Hz,1H), 3.62 (s, 4H), 3.24 (s, 3H), 3.13 (brs, 1H), 2.59 (s, 3H), 1.99 (d, J = 6.6Hz, 4H), 1.24 (d, J = 9.3 Hz, 4H). Example 33: 2'-chloro-5'-methoxy-6-methyl-N-(6-{[(1r,3r)-3-methoxycyclobutyl]amino}-[1,3]thiazo[4,5-c]pyridin-2-yl)-[4,4'-bipyridine]-3-carboxamide (C-24) As in Example 32, the preparation was carried out using the intermediate from step 3 (N-{6-chloro-[1,3]thiazo[4,5-c]pyridin-2-yl}-N-[(4-methoxyphenyl)methyl]carbamate tert-butyl ester, 1 g, 2.464 mmol, 1 equivalent) and (1r,3r)-3-methoxycyclobutane-1-amine (0.30 g, 2.957 mmol, 1.2 equivalent).

[0183] LC-MS (ES + m / z: 511.20 (M+H) + 1H NMR (300 MHz, DMSO-d6) δ 12.78 (s, 1H), 8.83 (s, 1H), 8.48 (s,1H), 8.17 (s, 1H), 7.56 (s, 1H), 7.44 (s, 1H), 6.86 – 6.74 (m, 2H), 4.17 (d,J = 6.3 Hz, 1H), 4.00 (s, 1H), 3.62 (s, 3H), 3.15 (s, 3H), 2.60 (s, 3H), 2.27 (d, J = 4.7 Hz, 2H), 2.14 (t, J = 6.1 Hz, 2H). Example 34: 2'-Chloro-5'-methoxy-6-methyl-N-{6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-23) (1s,3s)-3-(methoxymethyl)cyclobutane-1-ol Under a nitrogen atmosphere at -78°C, trisec-butylborohydride (12.5 g, 65.7 mmol, 1.50 equivalent) was added dropwise to a stirred solution of 3-(methoxymethyl)cyclobutane-1-one (5.00 g, 43.8 mmol, 1.00 equivalent) in 100 mL of THF. The resulting mixture was stirred at -78°C for 1 hour under a nitrogen atmosphere. The mixture was alkalized to pH 9 using a saturated aqueous solution of Na₂CO₃. The resulting mixture was extracted with EtOAc (3 × 50 mL). The combined organic layers were washed with water (1 × 50 mL) and dried over anhydrous Na₂SO₄. After filtration, the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (2:1) to give (1s,3s)-3-(methoxymethyl)cyclobutane-1-ol (2.9 g, 56.9% yield).

[0184] 4-Chloro-5-nitro-2-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]pyridine Under a nitrogen atmosphere at 0 °C, DIAD (6.95 g, 34.4 mmol, 1.50 equivalent) was added dropwise to a stirred solution of 4-chloro-5-nitropyridin-2-ol (4.00 g, 22.9 mmol, 1.00 equivalent) and PPh3 (9.02 g, 34.4 mmol, 1.5 equivalent) in THF (60 mL). The resulting mixture was stirred at room temperature under a nitrogen atmosphere for 2 h, diluted with DCM (60 mL), and concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (5:1) to give 4-chloro-5-nitro-2-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]pyridine (3.00 g, 48.0% yield).

[0185] 4-Chloro-6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]pyridine-3-amine At room temperature, Fe (3.07 g, 55.0 mmol, 5.00 equivalent) and ammonium chloride (5.88 g, 110 mmol, 10.0 equivalent) were added fractionally to a stirred solution of 4-chloro-5-nitro-2-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]pyridine (3.00 g, 11.0 mmol, 1.0 equivalent) in ethanol (30 mL) and water (6 mL). The resulting mixture was stirred at 80 °C for 2 h, filtered, and the filter cake was washed with ethanol (30 mL) (3 × 10 mL). The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (10:1) to give 4-chloro-6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]pyridine-3-amine (2.5 g, 94% yield).

[0186] 6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]-[1,3]thiazo[4,5-c]pyridine-2-amine At room temperature, concentrated hydrochloric acid (0.14 mL, 4.74 mmol, 2.30 equivalence) was added dropwise to a stirred solution of 4-chloro-6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]pyridine-3-amine (500 mg, 2.06 mmol, 1.00 equivalence) and potassium thiocyanate (600 mg, 6.18 mmol, 3.00 equivalence) in dioxane (30 mL). The resulting mixture was stirred overnight at 110 °C, cooled, and concentrated under reduced pressure. The mixture was alkalized to pH 8 using DIEA, and the residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yields 6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]-[1,3]thiazo[4,5-c]pyridine-2-amine (120 mg, 22% yield).

[0187] 2'-Chloro-5'-methoxy-6-methyl-N-{6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide At room temperature, DCC (326 mg, 1.58 mmol, 3.50 equivalent) and DMAP (193 mg, 1.58 mmol, 3.50 equivalent) were added fractionally to a stirred solution of 6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]-[1,3]thiazo[4,5-c]pyridine-2-amine (120 mg, 0.45 mmol, 1.00 equivalent) in a DCM (2.5 mL) container. The resulting mixture was stirred at room temperature for 2 hours and concentrated under reduced pressure. The residue was dissolved in DMSO (2 mL) and purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yielded 2'-chloro-5'-methoxy-6-methyl-N-{6-[(1r,3r)-3-(methoxymethyl)cyclobutoxy]-[1,3]thiazo[4,5-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (14.4 mg, 6.0% yield).

[0188] LC-MS (ES + m / z: 526.0 (M+H) + 1 H NMR (400 MHz, DMSO-d6) δ 12.99 (s, 1H), 8.84 (s, 1H), 8.60 (s,1H), 8.16 (s, 1H), 7.58 (s, 1H), 7.47 (s, 1H), 7.41 – 7.37 (m, 1H), 5.22 (p,J = 6.8 Hz, 1H), 3.60 (s, 3H), 3.41 (d, J = 6.8 Hz, 2H), 3.29 (s, 3H), 2.60(s, 3H),2.49(s,1H) 2.27 (m, 2H), 2.20 (m, 2H). Example 35: 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (C-10) [1,3]Thiazo[4,5-c]pyridine-2-amine At room temperature, HCl (0.35 mL) was added to a stirred solution of 4-chloropyridin-3-amine (2.0 g, 15.50 mmol, 1.00 equivalent) and potassium thiocyanate (4.54 g, 46.67 mmol, 3.00 equivalent) in dioxane (50 mL). The resulting mixture was stirred overnight at 110 °C and cooled to room temperature. The precipitated solid was collected by filtration and washed with EtOAc (3 × 10 mL). The resulting mixture was used directly for the next step without further purification. This yielded [1,3]thiazo[4,5-c]pyridin-2-amine (1.0 g, 43% yield).

[0189] 2'-Chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide Under nitrogen atmosphere at room temperature, DCC (95 mg, 0.46 mmol, 3.50 equivalent) and DMAP (56 mg, 0.46 mmol, 3.50 equivalent) were added to a mixture of [1,3]thiazo[4,5-c]pyridine-2-amine (20 mg, 0.132 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 44 mg, 0.15 mmol, 1.20 equivalent) in a stirred DCM (3 mL). The resulting mixture was stirred overnight, filtered, and the filter cake was washed with DCM (3 × 3 mL). The filtrate was concentrated under reduced pressure, and the crude product (35 mg) was purified by preparative-grade HPLC using the following conditions (column: XBridge Shield RP18 OBD column 30). 150 mm, 5 m; mobile phase A: water (10 mmol / L NH4HCO3 + 0.1% NH3·H2O), mobile phase B: ACN; flow rate: 60 mL / min; gradient: 15% B to 35% B over 8 min; wavelength: 254 nm / 220 nm; RT1 (min): 8.4), yielding 2'-chloro-5'-methoxy-6-methyl-N-{[1,3]thiazo[4,5-c]pyridin-2-yl}-[4,4'-bipyridine]-3-carboxamide (23.6 mg, 42% yield).

[0190] LC-MS (ES+) m / z: 410.00 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) d13.11 (brs, 1H), 8.98 (s, 1H), 8.91 (s,1H), 8.36 (d, J = 5.3 Hz, 1H), 8.15 (s, 1H), 7.99 (d, J = 5.3 Hz, 1H), 7.55 (s,1H), 7.42 (s, 1H), 3.60 (s, 3H), 2.60 (s, 3H). Intermediate B: 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid 2-Chloro-3-fluoro-5-methoxypyridine Under a nitrogen atmosphere at room temperature, K₂CO₃ (46.84 g, 338 mmol, 2.00 equivalent) was added to a stirred solution of 6-chloro-5-fluoropyridin-3-ol (25.0 g, 169 mmol, 1.00 equivalent) and MeI (36.2 g, 255 mmol, 1.51 equivalent) in acetone (500 mL). The resulting mixture was stirred for 2 hours and concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with petroleum ether / ethyl acetate (8 / 1) to give crude 2-chloro-3-fluoro-5-methoxypyridine (20.0 g, 73% yield, 61% purity) as a white solid.

[0191] 2-Chloro-3-fluoro-4-iodo-5-methoxypyridine A solution of 2-chloro-3-fluoro-5-methoxypyridine (12.0 g, 74.27 mmol, 1.00 equivalent) and n-butyllithium (36 mL, 2.4 M n-hexane solution, 1.20 equivalent) in THF (200 mL) was stirred at 60 °C for 1 hour under a nitrogen atmosphere. At -60 °C, a solution of I2 (24.51 g, 96.55 mmol, 1.30 equivalent) in THF (100 mL) was added dropwise to the mixture over 1 hour. The resulting mixture was stirred at room temperature for another 2 hours. The reaction was quenched at 0 °C by adding water / ice and NH4Cl (200 mL). The resulting mixture was extracted with EtOAc (3 × 200 mL). The combined organic layers were washed with brine (3 × 100 mL), dried over anhydrous Na2SO4, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography and eluted with petroleum ether / ethyl acetate (1 / 1) to give 2-chloro-3-fluoro-4-iodo-5-methoxypyridine (12.0 g, 56% yield, 86% purity) as a white solid.

[0192] 2'-Chloro-3'-Fluoro-5'-Methoxy-6-methyl-[4,4'-Bipyridine]-3-carboxylic acid methyl ester Under a nitrogen atmosphere at room temperature, Pd(dppf)Cl2 (0.48 g, 0.66 mmol, 0.19 equivalent) and K2CO3 (1.22 g, 8.80 mmol, 2.53 equivalent) were added to a stirred solution of 2-chloro-3-fluoro-4-iodo-5-methoxypyridine (1.0 g, 3.47 mmol, 1.00 equivalent) and 6-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborpentane-2-yl)pyridine-3-carboxylate (0.58 g, 2.08 mmol, 0.60 equivalent) in dioxane (10.00 mL) and water (2.00 mL). The resulting mixture was stirred at 80 °C for 16 hours under a nitrogen atmosphere. The mixture was filtered, and the filter cake was washed with 1,4-dioxane (3 × 10 mL). The filtrate was concentrated under reduced pressure and purified by silica gel column chromatography, eluted with petroleum ether / ethyl acetate (2 / 1) to give methyl 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (262 mg, 24% yield, 50.4% purity) as a pale yellow solid.

[0193] Under a nitrogen atmosphere at 0 °C, methyl 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (5 g, 16.0 mmol, 1.0 equivalent) was added to a stirred solution of MeOH (25 mL) and water (25 mL). The resulting mixture was stirred at room temperature for 2 h and concentrated under reduced pressure. The residue was purified by reversed-phase chromatography under the following conditions (column: XSelect CSH preparative grade C18 OBD column, 19 × 150 mm, 5 μm; mobile phase A: water (0.05% FA), mobile phase B: acetonitrile; flow rate: 25 mL / min; gradient: 10% B to 31% B, 31% B over 7 min; wavelength: 254 / 220 nm; RT1 (min): 6.28) to give 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (2.50 g, 96% purity, 52% yield) as an off-white solid.

[0194] LC-MS (ES+) m / z 297 (M+H)+ Example 36: 2'-Chloro-3'-Fluoro-5'-Methoxy-N-{5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-42) Tributyl[(2-methoxyethoxy)methyl]stanane A solution of diisopropylamine (6.52 g, 64.4 mmol, 1.25 equivalents) in THF (150 mL) was treated with butyllithium (1.6 M n-hexane solution) (4.95 g, 77.3 mmol, 1.50 equivalents) at -78 °C for 30 min. Tributyltin (15.0 g, 51.5 mmol, 1.00 equivalents) was added dropwise in portions at -78 °C. The resulting mixture was stirred at 0 °C for another 40 min. 1-(chloromethoxy)-2-methoxyethane (6.42 g, 51.5 mmol, 1.00 equivalents) was added dropwise in portions to the above mixture at -78 °C over 30 min. The resulting mixture was stirred at room temperature for another 1 h. The reaction was quenched at room temperature by the addition of saturated NH4Cl aqueous solution (100 mL), and extraction was performed using EtOAc (3 × 100 mL). The combined organic layers were washed with brine (1 × 100 mL) and dried over anhydrous Na₂SO₄. The filtrate was concentrated under reduced pressure and purified by silica gel chromatography, eluting with petroleum ether / ethyl acetate (20:1) to give tributyl[(2-methoxyethoxy)methyl]stanane (7 g, 36% yield) as a colorless oil.

[0195] N-{5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate ethyl ester A solution of N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (Example 22, step 1, 3.00 g, 11.6 mmol, 1.00 equivalent), Pd(PPh3)2Cl2 (0.810 g, 1.16 mmol, 0.100 equivalent), and tributyl[(2-methoxyethoxy)methyl]stannane (6.60 g, 17.40 mmol, 1.50 equivalent) in DMF (30 mL) was stirred at 120 °C for 4 hours under a nitrogen atmosphere. The reaction was quenched at room temperature by adding saturated aqueous NH4Cl solution (100 mL), and extracted with EtOAc (3 × 100 mL). The combined organic layers were washed with brine (1 × 100 mL) and dried over anhydrous Na2SO4. The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. Concentration of the mixture under reduced pressure yielded N-{5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate as a yellow solid (1.5 g, 41% yield, 95% purity).

[0196] 5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidine-2-amine A solution of N-{5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (500 mg, 1.60 mmol, 1.00 equivalent) and sodium methoxide (5–5.4 M methanol solution) (86.5 mg, 1.60 mmol, 1.00 equivalent) in methanol (5 mL) was stirred overnight at room temperature under a nitrogen atmosphere. The reaction was quenched at room temperature by adding water (1 mL). The resulting mixture was concentrated under reduced pressure and purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yields a yellow solid of 5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidine-2-amine (55 mg, 14% yield).

[0197] 2'-Chloro-3'-Fluoro-5'-Methoxy-N-{5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of 5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidine-2-amine (55.0 mg, 0.208 mmol, 1.00 equivalent), dicyclohexylcarbodiimide (150 mg, 0.728 mmol, 3.50 equivalent), DMAP (89.0 mg, 0.728 mmol, 3.50 equivalent) and 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate B, 61.7 mg, 0.208 mmol, 1.00 equivalent) in dichloromethane (2 mL) was stirred at room temperature for 2 hours under a nitrogen atmosphere. The resulting mixture was concentrated under reduced pressure, and the residue was purified by reversed-phase chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 30% gradient over 10 minutes; detector, UV 254 nm. This yielded 2'-chloro-3'-fluoro-5'-methoxy-N-{5-[(2-methoxyethoxy)methyl]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (33.2 mg, 31% yield, 95% purity).

[0198] LC-MS (ES + m / z: 519.05(M+H) + 1H NMR (300 MHz, DMSO-d6)δ 13.49 (s, 1H), 9.16 (s, 1H), 9.05 (s, 1H), 8.19 (s, 1H), 7.53 (s, 1H), 4.73 (s, 2H), 3.74 – 3.65 (m, 2H), 3.55 – 3.45 (m, 2H), 3.34 (s, 3H), 3.25 (s, 3H), 2.62 (s, 3H). Example 37: 2'-Chloro-N-[5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-43) N-[5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate ethyl ester Under a nitrogen atmosphere at room temperature, potassium tert-butoxide (6.59 g, 58.74 mmol, 3.00 equivalent) was added to a mixture of 2-cyclopropoxyethanol (2.0 g, 19.58 mmol, 1.00 equivalent) and N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (Example 22, Step 1, 7.60 g, 29.37 mmol, 1.50 equivalent) in NMP (20 mL) under stirring. The resulting mixture was stirred at 80 °C for 2 hours under a nitrogen atmosphere. The mixture was then cooled to room temperature. The resulting mixture was filtered, and the filter cake was washed with NMP (10 mL) (2 × 5 mL). The filtrate was concentrated under reduced pressure, and the residue was purified by reversed-phase chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 100% gradient over 10 minutes; detector, UV 254 nm. This yielded N-[5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate (1.2 g, 19% yield), as a pale yellow solid.

[0199] LC-MS (ES + m / z: 325.20 (M+H) + 1 5-(2-Cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine A mixture of N-[5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate (1.2 g, 3.70 mmol, 1.00 equivalent) and sodium methoxide (5–5.4 M methanol solution) (0.40 g, 7.400 mmol, 2.00 equivalent) in methanol (48 mL) was stirred overnight at 80 °C under a nitrogen atmosphere. The mixture was cooled to room temperature. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 100% gradient over 10 min; detector, UV 254 nm. This yields 5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (300 mg, 32% yield) as a pale yellow solid.

[0200] 2'-Chloro-N-[5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide Under a nitrogen atmosphere at room temperature, DMAP (70 mg, 0.57 mmol, 3.19 equivalents) and dicyclohexylcarbodiimide (130 mg, 0.630 mmol, 3.51 equivalents) were added to a stirred mixture of 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate A, 50 mg, 0.17 mmol, 1.10 equivalents) and 5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (50 mg, 0.198 mmol, 1.10 equivalents) in dichloromethane (1 mL). The resulting mixture was filtered, and the filter cake was washed with DCM (1 mL) (3 × 1 mL). The filtrate was concentrated under reduced pressure. The crude product (50 mg) was purified by preparative-grade HPLC using the following conditions (column: XBridge Shield RP18 OBD column 30). 150 mm, 5 m; mobile phase A: water (10 mmol / L NH4HCO3), mobile phase B: ACN; flow rate: 60 mL / min; gradient: 35% B to 59% B over 7 min; wavelength: 254 nm / 220 nm; RT1 (min): 5.7), yielding 2'-chloro-N-[5-(2-cyclopropoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (25.5 mg, 28% yield, 99.6% purity).

[0201] LC-MS (ES + m / z: 513.25 (M+H) + 1 1 H NMR (400 MHz, DMSO- d 6) δ 13.18 (s, 1H), 8.93 (brs, 1H), 8.87 (s,1H), 8.16 (s, 1H), 7.56 (s, 1H), 7.43 (s, 1H), 4.45 (m, 2H), 3.79 (m, 2H), 3.62 (s, 3H), 3.37 (m, 1H), 2.60 (s, 3H), 0.54 – 0.39 (m, 4H). Example 38: 2'-Chloro-N-[5-(2-ethoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-44) 5-(2-ethoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine A solution of 2-ethoxyethanol (7.60 g, 84.33 mmol, 12.12 equivalents) was treated with NaH (1.87 g, 46.67 mmol, 6.71 equivalents, 60%) at -20 °C for 40 minutes under a nitrogen atmosphere. Then, N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (Example 22, Step 1, 6.00 g, 6.95 mmol, 1.00 equivalents, 30%) was added dropwise at room temperature. The resulting mixture was stirred overnight at 100 °C. The reaction was quenched at 0 °C by adding water. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 100% gradient over 10 minutes; detector, UV 254 nm. This yielded 5-(2-ethoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine as a brown solid (400 mg, 24% yield, 89% purity).

[0202] LC-MS (ES + m / z: 241.1 (M+H) + 1 2'-Chloro-N-[5-(2-ethoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide At room temperature, dicyclohexylcarbodiimide (222.11 mg, 1.07 mmol, 3.00 equivalent) and DMAP (131.51 mg, 1.07 mmol, 3.00 equivalent) were added to a stirred solution of 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (81.18 mg, 0.35 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (100.00 mg, 0.35 mmol, 1.00 equivalent) in dichloromethane (2 mL). The resulting mixture was stirred overnight, concentrated, and the residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 100% gradient over 10 minutes; detector, UV 254 nm. This yielded 2'-chloro-N-[5-(2-ethoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (29 mg, 16% yield, 98% purity).

[0203] LC-MS (ES + m / z: 501.10 (M+H) + 1 ¹H NMR (300 MHz, DMSO-d⁶) δ 13.16 (s, ¹H), 8.99 (s, ¹H), 8.86 (s, ¹H), 8.18 (s, ¹H), 7.59 (s, ¹H), 7.48 (s, ¹H), 4.4 (m, 2H), 3.73 (m, 2H), 3.6 (s, 3H) (masked by DMSO peak), 3.51 (q, J = 7.0 Hz, 2H), 2.51 (s, 3H), 1.13 (t, J = 6.9 Hz, 3H). Example 39: 2'-chloro-5'-methoxy-N-[5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-47) Ethyl N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate Under a nitrogen atmosphere at room temperature, ethoxycarbonyl isothiocyanate (8.00 g, 60.98 mmol, 2.00 equivalent) was added to a stirred solution of 2,4-dichloropyrimidin-5-amine (5.00 g, 30.50 mmol, 1.00 equivalent) in methanol (150 mL). The resulting mixture was stirred at 60 °C for 30 min. The precipitated solid was collected by filtration and washed with methanol (3 × 15 mL). This yielded N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (5.00 g, 100% purity, 63% yield) as a yellow solid.

[0204] N-[5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate ethyl carbamate A solution of N-{5-chloro-[1,3]thiazo[5,4-d]pyrimidin-2-yl}carbamate (2.00 g, 7.73 mmol, 1.00 equivalent) and 3-methoxy-1-propanol (1.39 g, 15.46 mmol, 2.00 equivalent) and K₂CO₃ (3.21 g, 23.19 mmol, 3.00 equivalent) in NMP (20 mL) was stirred overnight at 80 °C. The resulting mixture was filtered, and the filter cake was washed with dichloromethane (2 × 10 mL). The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH₄HCO₃), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields N-[5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate (2.50 g, 93.5% yield) as a light brown solid.

[0205] 5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine A solution of N-[5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]carbamate (2.50 g, 8.00 mmol, 1.00 equivalent) and MeONa (1.30 g, 24.01 mmol, 3.00 equivalent) in MeOH (25 mL) was stirred overnight at room temperature. The resulting mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography, eluting with dichloromethane / methanol (10:1) to give 5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-amine (600.00 mg, 31.2% yield, 94.50% purity) as a brownish-yellow solid.

[0206] 2'-Chloro-5'-methoxy-N-[5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of 5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (100.00 mg, 0.41 mmol, 1.00 equivalent) and 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate B, 115.99 mg, 0.41 mmol, 1.00 equivalent), DCC (300.55 mg, 1.45 mmol, 3.50 equivalent), and DMAP (177.96 mg, 1.45 mmol, 3.50 equivalent) in DCM (2 mL) was stirred at room temperature for 2 hours. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yielded 2'-chloro-5'-methoxy-N-[5-(3-methoxypropoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (50.10 mg, 23.7% yield, 98.90% purity).

[0207] LC-MS (ES + m / z: 501.00 (M+H) + 1H NMR (300 MHz, DMSO-d6): [δ 13.17 (s, 1H), 8.98 (s, 1H), 8.85 (s,1H), 8.17 (s, 1H), 7.59 (s, 1H), 7.48 (s, 1H), 4.40 (t, J = 6.5 Hz, 2H), 3.62(s, 3H), 3.48 (t, J = 6.2 Hz, 2H), 2.61 (s, 3H), 1.99 (p, J = 6.4 Hz, 2H)]. Example 40: 2'-Chloro-N-{5-[2-(dimethylamino)ethoxy]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-48) DCC (104.32 mg, 0.50 mmol, 3.00 equivalent) and DMAP (61.77 mg, 0.50 mmol, 3.00 equivalent) were added dropwise to a stirred solution of 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (intermediate B, 50.00 mg, 0.16 mmol, 1.00 equivalent) in dichloromethane (2 mL). The resulting mixture was stirred at room temperature for another 2 hours. The resulting mixture was then concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yielded 2'-chloro-N-{5-[2-(dimethylamino)ethoxy]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxamide (25.00 mg, 28.2% yield, 99.2% purity).

[0208] LC-MS (ES + m / z: 505.00 (M+H) + 1 H NMR (300 MHz, DMSO-d6) δ 13.30 (s, 1H), 9.01 (d, J = 2.7 Hz, 2H), 8.19 (s, 1H), 7.53 (d, J = 1.5 Hz, 1H), 4.51 – 4.46 (m, 2H), 3.74 (s, 3H),3.72 – 3.67 (m, 2H), 2.62 (s, 3H). Example 41: 2'-(difluoromethyl)-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-50) 2'-Chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid methyl ester A solution of methyl 4-bromo-6-methylpyridine-3-carboxylate (2.00 g, 8.69 mmol, 1.00 equivalent), Pd(dppf)·CH₂Cl₂ (0.710 g, 0.869 mmol, 0.100 equivalent), K₂CO₃ (2.40 g, 17.4 mmol, 2.00 equivalent), and 2-chloro-5-methoxypyridine-4-ylboronic acid (1.63 g, 8.69 mmol, 1.00 equivalent) in 1,4-dioxane (20 mL) was stirred overnight at 80 °C under nitrogen atmosphere. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH₄HCO₃), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields methyl 2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate as a brown solid (2.0 g, 78.5% yield).

[0209] 6-(2-chloro-5-methoxypyridin-4-yl)-1-{[2-(trimethylsilyl)ethoxy]methyl}pyrazolo[4,3-b]pyridine-5-carboxylic acid methyl ester A solution of methyl 6-bromo-1-{[2-(trimethylsilyl)ethoxy]methyl}pyrazolo[4,3-b]pyridine-5-carboxylate (2.00 g, 5.17 mmol, 1.00 equivalent), Pd(dppf)Cl2 (379 mg, 0.513 mmol, 0.100 equivalent), Na2CO3 (1.09 g, 10.3 mmol, 2.00 equivalent), and 2-chloro-5-methoxypyridin-4-ylboronic acid (970 mg, 5.17 mmol, 1.00 equivalent) in DMSO (20 mL) was stirred at 80 °C for 2 hours under a nitrogen atmosphere. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. The resulting mixture was concentrated under reduced pressure. This yielded methyl 6-(2-chloro-5-methoxypyridin-4-yl)-1-{[2-(trimethylsilyl)ethoxy]methyl}pyrazolo[4,3-b]pyridine-5-carboxylate as a yellow solid (1.7 g, 32.2% yield).

[0210] 2'-Formyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate A solution of methyl 2'-vinyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (1.70 g, 5.98 mmol, 1.00 equivalent), potassium osmium tetroxide (VI) dihydrate (0.040 g, 0.120 mmol, 0.020 equivalent), and NaIO4 (3.84 g, 17.9 mmol, 3.00 equivalent) in acetonitrile (20 mL) and water (4 mL) was stirred overnight at room temperature under a nitrogen atmosphere. The reaction mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields methyl 2'-formyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate as a black solid (800 mg, 46.7% yield).

[0211] 2'-(difluoromethyl)-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid methyl ester Under a nitrogen atmosphere at 0 °C, methyl 2'-formyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (800 mg, 2.79 mmol, 1.00 equivalent) was added dropwise to a stirred solution of dichloromethane (10 mL). The resulting mixture was stirred overnight at room temperature. The reaction was quenched by adding water (10 mL) and concentrated under reduced pressure. The residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 45% gradient over 10 minutes; detector, UV 254 nm. This yields methyl 2'-(difluoromethyl)-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (500 mg, 58.0% yield), which is a dark oil.

[0212] 2'-(difluoromethyl)-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid A solution of methyl 2'-(difluoromethyl)-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (500 mg, 1.62 mmol, 1.00 equivalent) and LiOH·H₂O (272 mg, 6.49 mmol, 4.00 equivalent) in methanol (9 mL) and water (3 mL) was stirred overnight at room temperature under a nitrogen atmosphere. The mixture was acidified to pH 6 with HCl (2 M). The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH₄HCO₃), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields 2'-(difluoromethyl)-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (300 mg, 62.8% yield), which is a brown oil.

[0213] 2'-(difluoromethyl)-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of 2'-(difluoromethyl)-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (100 mg, 0.340 mmol, 1.00 equivalent), TCFH (334 mg, 1.19 mmol, 3.50 equivalent), 1-methyl-1H-imidazole (97.7 mg, 1.19 mmol, 3.50 equivalent), and 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (84.6 mg, 0.374 mmol, 1.10 equivalent) in acetonitrile (2 mL) was stirred overnight at room temperature under a nitrogen atmosphere. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yielded 2'-(difluoromethyl)-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (29.8 mg, 17.4% yield, 96.8% purity).

[0214] LC-MS (ES + m / z: 503.00(M+H) + 1H NMR (300 MHz, DMSO-d6) δ 13.19 (s, 1H), 8.97 (s, 1H), 8.87 (s,1H), 8.46 (s, 1H), 7.73 (s, 1H), 7.47 (s, 1H), 7.00 (s, 1H), 4.52 – 4.43 (m,2H), 3.70 (d, J = 2.7 Hz, 5H), 3.31 (s, 3H), 2.62 (s, 3H). Example 42: 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-51) 2'-Vinyl-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid methyl ester Methyl 2'-chloro-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (7.0 g, 22.52 mmol, 1.00 equivalent) and 2-vinyl-4,4,5,5-tetramethyl-1,3,2-dioxoborane (6.94 g, 45.05 mmol, 2.00 equivalent) were added to a solution of dioxane (100 mL) and water (10 mL) with K₂CO₃ (9.34 g, 67.587 mmol, 3.00 equivalent) and Pd(dppf)Cl₂ (1.65 g, 2.253 mmol, 0.10 equivalent). After stirring at 100 °C for 1 hour under a nitrogen atmosphere, the resulting mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography and eluted with PE / EA (5:1) to give methyl 2'-vinyl-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate as a yellow solid (5.0 g, 73.4% yield, 95% purity).

[0215] methyl 3'-fluoro-2'-formyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate Under a nitrogen atmosphere at room temperature, a solution of methyl 2'-vinyl-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (1.0 g, 3.30 mmol, 1.00 equivalent) in acetonitrile (10 mL) and water (1 mL) was treated with NaIO4 (2.12 g, 9.924 mmol, 3.00 equivalent). Then, a solution of potassium osmium tetroxide (VI) dihydrate (0.04 g, 0.099 mmol, 0.03 equivalent) in water (1 mL) was added in portions at 0 °C. The resulting mixture was stirred for 2 hours under a nitrogen atmosphere at room temperature and filtered. The filter cake was then washed with MeCN (10 mL). The filtrate was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yielded methyl 3'-fluoro-2'-formyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate as a yellow solid (500.0 mg, 49.6% yield, 94.1% purity).

[0216] 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid methyl ester A solution of methyl 3'-fluoro-2'-formyl-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (500.0 mg, 1.64 mmol, 1.00 equivalent) and DAST (397.3 mg, 2.46 mmol, 1.50 equivalent) in DCM (10 mL) was stirred at 0 °C for 2 h under a nitrogen atmosphere. The reaction was quenched at 0 °C with water / ice (20 mL). The aqueous layer was extracted with dichloromethane (10 mL) and the organic layer was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 min; detector, UV 254 nm. This yields methyl 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate as a yellow solid (300.0 mg, 55.9% yield).

[0217] 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid A solution of methyl 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylate (300.0 mg, 0.91 mmol, 1.00 equivalent) and LiOH (110.1 mg, 4.59 mmol, 5.00 equivalent) in MeOH (5 mL) and water (0.5 mL) was stirred overnight at room temperature under a nitrogen atmosphere. The mixture was acidified to pH 6 with citric acid. The aqueous layer was extracted with ethyl acetate (10 mL). The organic layer was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography using the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yields 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid as a white solid (120.0 mg, 41.80% yield, 95.0% purity).

[0218] 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide A solution of 5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidine-2-amine (Example 22, 100 mg, 0.442 mmol, 1 equivalent), DMAP (161.99 mg, 1.326 mmol, 3 equivalents), dicyclohexylcarbodiimide (273.59 mg, 1.326 mmol, 3 equivalents), and 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carboxylic acid (138.01 mg, 0.442 mmol, 1 equivalent) in dichloromethane (1 mL) was stirred overnight at room temperature under a nitrogen atmosphere. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 50% gradient over 10 minutes; detector, UV 254 nm. This yielded 2'-(difluoromethyl)-3'-fluoro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (20 mg, 8.6% yield, 98.8% purity).

[0219] LC-MS (ES + m / z: 521.15 (M+H) + 1 H NMR (400 MHz, DMSO- d 6) :δ 13.32 (s, 1H), 8.99 (d, J = 26.5 Hz, 2H), 8.43 (s, 1H), 7.48 (s, 1H), 7.13 (t, J = 53.1 Hz, 1H), 4.50 – 4.43 (m, 2H), 3.81 (s, 3H), 3.72 – 3.65 (m, 2H), 2.61 (s, 3H). Example 43: [(2Z)-2-{2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carbonylimino}-5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-1-yl]methoxyphosphonic acid (C-53) [(2Z)-2-{2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carbonylimino}-5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-1-yl]di-tert-butyl methylphosphate At room temperature, Cs₂CO₃ (133.83 mg, 0.41 mmol, 1 equivalent) and KI (3.4 mg, 0.02 mmol, 0.1 equivalent) were added to a solution of 2'-chloro-5'-methoxy-N-[5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-2-yl]-6-methyl-[4,4'-bipyridine]-3-carboxamide (100 mg, 0.205 mmol, 1 equivalent) and di-tert-butyl chloromethyl phosphate (79.69 mg, 0.307 mmol, 1.5 equivalent) in NMP (2 mL) with stirring. The resulting mixture was stirred overnight at 40 °C. The mixture was filtered and the filter cake was washed with NMP (2 mL) (3 × 1 mL). The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (10 mmol / L NH4HCO3), in a 10% to 80% gradient over 10 minutes; detector, UV 254 nm, to give [(2Z)-2-{2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carbonylimine}-5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-1-yl]methyl ditert-butyl phosphate (60 mg, 41.20% yield) as a brown solid.

[0220] [(2Z)-2-{2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carbonylimino}-5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-1-yl]methoxyphosphonic acid A solution of [(2Z)-2-{2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carbonylimino}-5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-1-yl]methyl di-tert-butyl phosphate (60 mg, 0.067 mmol, 1 equivalent) was stirred in H₂O (0.5 mL) and HCOOH (0.5 mL). The resulting mixture was stirred at 35 °C for 3 hours. The resulting mixture was concentrated under reduced pressure. The residue was purified by reversed-phase rapid chromatography under the following conditions: column, C18 silica gel; mobile phase, water containing acetonitrile (0.1% FA), in a 10% to 80% gradient over 10 minutes; detector, UV 254 nm, to give [(2Z)-2-{2'-chloro-5'-methoxy-6-methyl-[4,4'-bipyridine]-3-carbonylimino}-5-(2-methoxyethoxy)-[1,3]thiazo[5,4-d]pyrimidin-1-yl]methoxyphosphonic acid (22.8 mg, 57.07% yield, 95.0% purity).

[0221] LC-MS (ES + m / z: 597.15 [M+1] + 1 H NMR (400 MHz, DMSO- d 6) δ 9.28 (s, 1H), 8.92 (s, 1H), 8.16 (s, 1H), 7.45 (s, 1H), 7.30 (s, 1H), 5.99 (d, J = 10.4 Hz, 2H), 4.50 – 4.40 (m, 2H), 3.70 – 3.66 (m, 2H), 3.65 (s, 3H), 3.30 (s, 3H), 2.57 (s, 3H). Example 44: 2'-Chloro-5'-methoxy-N-(5-(2-(methoxy-d3)ethoxy)thiazo[5,4-d]pyrimidin-2-yl)-6-methyl-[4,4'-bipyridine]-3-carboxamide (C-52) ((2-(methoxy-d3)ethoxy)methyl)benzene At 0 °C, NaH (12.6 g, 526 mmol, 2.00 equivalent) was added to a stirred solution of benzylethylene glycol (40.0 g, 263 mmol, 1.00 equivalent) in DMF (400 mL), and the mixture was stirred for 0.5 h. Then, iodomethane-d3 (76.2 g, 526 mmol, 2.00 equivalent) was added, and the reaction mixture was stirred at 25 °C for 12 h. The reaction was monitored by TLC. The reaction was quenched at 0 °C by adding water (5.00 mL). The aqueous layer was extracted with EtOAc (3 × 5.00 mL). The combined organic layers were dried under vacuum. The residue was purified by silica gel column chromatography, eluting with PE / EA (10:1) to give {[2-(2H3)methoxyethoxy]methyl}benzene (40.0 g, 90.0% yield) as a colorless oil.

[0222] 2-(methoxy-d3)ethanol A mixture of ((2-(methoxy-d3)ethoxy)methyl)benzene (2.00 g, 11.8 mmol, 1.00 equivalent) and Pd / C (200 mg, 10% wt) in THF (20.0 mL) was stirred at 25 °C for 12 h under a hydrogen atmosphere. The reaction was monitored by TLC. The catalyst was filtered off, and the crude product was used directly in the next step.

[0223] 5-(2-(methoxy-d3)ethoxy)thiazo[5,4-d]pyrimidine-2-amine Sodium hydride (60% in oil, 129 mg, 3.22 mmol, 6.00 equivalent) was added to a stirred solution of 2-(methoxy-d3)ethanol (254 mg, 3.22 mmol, 6.00 equivalent) in THF (3.50 mL) at 0 °C, and the mixture was stirred for 0.5 h. Then, 5-chloro-[1,3]thiazo[5,4-d]pyrimidine-2-amine (100 mg, 0.536 mmol, 1.00 equivalent) was added, and the reaction mixture was stirred at 70 °C for 24 h. The reaction was quenched at 0 °C by adding water (3.00 mL), and the mixture was then extracted with EtOAc (3 × 5.00 mL). The combined extracts were concentrated under reduced pressure. The crude product was purified by preparative-grade HPLC under the following conditions (0.08% NH4HCO3) to give 5-(2-(methoxy-d3)ethoxy)thiazo[5,4-d]pyrimidine-2-amine as a white solid (70 mg, 51.5% yield, 90.3% purity).

[0224] LC-MS (ES+ m / z: 230[M+1] + 2'-Chloro-5'-methoxy-N-(5-(2-(methoxy-d3)ethoxy)thiazo[5,4-d]pyrimidin-2-yl)-6-methyl-[4,4'-bipyridine]-3-carboxamide A mixture of 5-[2-(2H3)methoxyethoxy]-[1,3]thiazo[5,4-d]pyrimidine-2-amine (21.4 mg, 0.094 mmol, 2.00 equivalent) and DMAP (20.0 mg, 0.165 mmol, 3.50 equivalent) in DCM (0.500 mL) was stirred at 25 °C for 12 hours under air. The reaction was monitored by LCMS. The resulting mixture was diluted with DMF (1 mL). The crude product was purified by preparative-grade HPLC under the following conditions (column: XSelect CSH preparative-grade C18 OBD column, 19 × 150 mm, 5 μm; mobile phase A: water (0.1% FA), mobile phase B: acetonitrile; flow rate: 60 mL / min; gradient: 5% B to 5% B, 5% B over 1 min; wavelength: 254 / 220 nm; RT1 (min): 9.31; number of runs: 0) to give 2'-chloro-5'-methoxy-N-{5-[2-(2H3)methoxyethoxy]-[1,3]thiazo[5,4-d]pyrimidin-2-yl}-6-methyl-[4,4'-bipyridine]-3-carboxamide (10.2 mg, 43.7% yield, 99.8% purity).

[0225] LC-MS (ES + m / z: 490.00 (M+H) + 1 H NMR (400 MHz, DMSO- d 6): [δ 13.13 (s, 1H), 8.95 (s, 1H), 8.87 (s,1H), 8.17 (s, 1H), 7.57 (s, 1H), 7.45 (s, 1H), 4.57 – 4.42 (m, 2H), 3.75 –3.66 (m, 2H), 3.62 (s, 3H), 2.60 (s, 3H) ]. II. Biological Evaluation DNA helicase ADP-Glo ​​assay Polθ's ATPase activity is mediated through ADP-Glo TMThe kinase assay was determined by measuring ATP conversion. For the inhibition assay, a series of compounds were diluted at 10 concentration points in a 384-well format. Assay buffer (40 mM Tris HCl (pH=8.0), 20 mM MgCl2, 0.01% BSA, 1 mM DTT) containing Polθ-N (5 nM) and 400 nM ssDNA (5'-CCAGTGAATTGTTGCTCGGTACCTGCTAAC-3') was transferred to each well (5 μL). The plate was incubated at 25°C for 10 min. Subsequently, an equal volume (5 μL) of assay buffer containing 200 μM ATP was added to all wells, and the plate was incubated at 25°C for 4 h. After the kinase reaction, 10 μL of ADP-Glo ​​was added. TM The reagent was used to terminate the reaction and deplete the remaining ATP. The plate was incubated at 25°C for 1 hour. Next, 20 μL of kinase assay reagent was added to convert ADP to ATP, and the newly synthesized ATP was detected using a luciferase / luciferin reaction. After 1 hour of incubation, the luminescence signal was measured using Envision. High-value controls (DMSO and enzyme) with high luminescence signals indicated that the enzyme reaction was not inhibited, while low-value controls (10 μM of the example compound and enzyme) with low luminescence signals indicated that the enzyme reaction was completely inhibited. The percentage of inhibition was calculated using the formula “%inhibition = 100 × (high-value control - sample) / (high-value control - low-value control)”, and then the IC50 was generated using the four-parameter inhibition model in XLFit (Equation 201) by setting both the bottom and top of the curve as floating parameters. 50 Hill slope, maximum inhibition, etc.

[0226] DLD-1 BRCA2 (- / -) Clonogenic assay (CFA) The inhibition of cell growth following in vitro treatment with the drug was evaluated using a colony formation assay (CFA). Cells were harvested and adjusted to the desired density using culture medium. DLD-1 BRCA2 was cultured at a density of 1000 cells / well. (- / -) Alternatively, 100 cells / well of DLD-1 parental cells (for WT assay) can be seeded in 24-well plates and incubated overnight at 37°C and 5% CO2. The test compound is dissolved in DMSO to obtain a stock solution, which is then serially diluted in 384-well plates using a TECAN (EVO200) liquid handling station (for DLD-1 parental cells: 5 mM highest concentration, 3-fold dilution, 5 concentration points / for DLD-1 BRCA2). (- / -)(5 mM maximum concentration, 10-fold dilution, 5 concentration points). 1 μL / well of the compound from the source plate was manually transferred to the cell plate and incubated at 37°C, 5% CO2. The medium and compound were refreshed every 3 days. After 10 days of treatment, cells were fixed with 500 μL / well of 70% ethanol for 15 min, followed by staining of clones with 500 μL / well of 0.1% crystal violet and incubation at room temperature for 15 min. The plate was washed with HPLC water and dried overnight at room temperature. All wells were scanned at 680 nm using Li-Cor. Clones were dissolved in fresh 10% acetic acid (500 μL / well) for 20 min at room temperature. Aliquots (200 μL / well, duplicated) were transferred from each sample to a 96-well plate, and absorbance was read at 590 nm in Tecan. IC50 was calculated using Graphpad Prism by setting both the bottom and top of the curve as floating parameters. 50 (Negative controls were obtained only from cells treated with 0.1% DMSO; positive controls were only from culture medium).

[0227] Only DLD-1 BRCA2 was shown. (- / -) Data in cells. The compound showed >10,000 nM activity in WT cells.

[0228] Table 3

[0229] N / A: Not tested.

Claims

1. Compounds of Formula I: (I) Or its tautomers, stereoisomers, or pharmaceutically acceptable salts. in: Ring A is a 5-10 aryl or heteroaryl group, which contains 1 to 4 Y atoms independently selected from carbon, nitrogen, oxygen or sulfur; R 11 and R 12 Independently absent or independently selected from hydrogen, alkyl, halogen, haloalkyl, haloalkoxy, alkoxy, hydroxy, cyano, cyanoalkyl, carboxyl, alkoxycarbonyl, acylamino, aminocarbonyl, optionally substituted heteroaryl, hydroxyalkyl, cycloalkyl, hydroxyynyl, alkoxyalkyl, aminoalkyl, aminocarbonylalkyl, sulfonylalkyl, aminosulfonylalkyl, optionally substituted heteroaryl or optionally substituted heterocyclic alkyl, wherein m and n are independently integers from 0 to 10; Ar1 is a phenyl, heteroaryl, heterocyclic, bicyclic, bridged heterocyclic, or spirocyclic group, wherein each of the above rings is R a R b R c and R d Replace, where R a R b R c and R d Independently absent or independently selected from hydrogen, alkyl, halogen, haloalkyl, alkoxy, haloalkoxy, cycloalkyloxy, acyl, acylamino, monoalkylamino, dialkylamino, alkylsulfonyl, cyano, and hydroxyl; Cycle B is a 5-10 aryl or heteroaryl group containing 1-4 Y atoms independently selected from carbon, nitrogen, oxygen or sulfur, or a 4-10 saturated or unsaturated lactam, preferably a 5-7 saturated or unsaturated lactam. Optionally, cycle B is further substituted with an alkyl group, a halogen or a haloalkyl group. G can be a branched or unbranched, substituted or unsubstituted, saturated or unsaturated aliphatic hydrocarbon chain having 1-20 carbon atoms in its skeletal chain, or a heteroatom independently selected from nitrogen, oxygen or sulfur. When G is nitrogen, it is substituted. R 21 It is absent or selected from hydrogen, alkyl, halogen, haloalkyl, haloalkoxy, alkoxy, hydroxyl, cyano, cyanoalkyl, carboxyl, alkoxycarbonyl, amino, acylamino, aminocarbonyl, hydroxyalkyl, hydroxyynyl, alkoxyalkyl, optionally substituted aminoalkyl, aminocarbonylalkyl, sulfonylalkyl, aminosulfonylalkyl, optionally substituted alkoxyalkyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted cycloalkyl, optionally substituted phenyl, optionally substituted heteroaryl, optionally substituted heterocyclic, optionally substituted bicyclic heterocyclic, optionally substituted bridged heterocyclic, optionally substituted spirocyclic, or optionally substituted spirocyclic. Among them G, R 11 R 12 Or R 21 The substituents are independently selected from alkyl, cycloalkyl, cycloalkoxy, halogen, haloalkyl, haloalkoxy, alkoxy, alkoxyalkyl, hydroxy, carboxyl, and alkoxycarbonyl. Where R 11 R 12 Ar1 or R 21 The heteroatoms are independently selected from nitrogen, oxygen, or sulfur.

2. The compound of claim 1, wherein ring A is selected from the following: 。 3. The compound of claim 1 or 2, wherein Ar1 is... or , Where Z is selected from -N- or -C-; and R a R b R c and R d Independently absent or independently selected from hydrogen, alkyl, halogen, haloalkyl, alkoxy, haloalkoxy, cycloalkyloxy, acyl, acylamino, monoalkylamino, dialkylamino, alkylsulfonyl, cyano, and hydroxyl.

4. The compound according to any one of claims 1-3, wherein Ar1 is selected from: 。 5. The compound according to any one of claims 1-4, wherein Ar1 is selected from: 。 6. The compound according to any one of claims 1-5, wherein ring B is a 5-6 aryl or heteroaryl group containing three atoms Y1, Y2, Y3, wherein Y1, Y2, Y3 are independently absent or selected from carbon, nitrogen, oxygen, or sulfur; and optionally each of Y1, Y2, Y3 is further independently converted to carbon by C. 1-6 Alkyl, halogen or C 1-6 Halogenated alkyl substitution; Preferably, ring B is Where Y1, Y2, and Y3 are independently absent or selected from carbon and nitrogen; and the bonds... It represents a single bond or a double bond.

7. The compound according to any one of claims 1-6, wherein formula I is selected from: 。 8. The compound according to any one of claims 1-7, wherein R 21 It does not exist or is selected from the following: 。 9. The compound of claim 1, wherein... The ring A is ; Ar1 is Ra is selected from C 1-6 alkoxy groups; and R b R c and R d Independently selected from hydrogen, C 1-6 Alkyl, halogen, C 1-6 Halogenated alkyl groups; The ring B is Where Y1 is CH, Y2 is NH, and Y3 comes from CH or NH, and the bond... Represents a single or double bond; and G is oxygen; and optionally each of Y1 and Y3 is further independently constituting C. 1-6 Alkyl, halogen or C 1-6 Halogenated alkyl substitution; The R 21 Selected from the replaced C 1-6 Alkyl and substituted C 3-8 cycloalkyl; and R 21 The substituents are independently selected from C 3-8 Cycloalkoxy, C 1-6 Halogenated alkoxy groups and C 1-6 Alkyl group.

10. The compound of claim 9, wherein formula I is selected from: or Where Z is -N-; R 21 Selected from the replaced C 1-6 Alkyl and substituted C 3-8 cycloalkyl; and R 21 The substituents are independently selected from C 3-8 Cycloalkoxy, C 1-6 Halogenated alkoxy groups and C 1-6 alkoxy groups; and R b and R c Independently selected from hydrogen, C 1-6 Alkyl, halogen, C 1-6 Halogenated alkyl groups.

11. The compound of claim 9 or 10, wherein R 21 Selected from the following: ;as well as Selected from the following: 。 12. The compound according to any one of claims 1-11, wherein the compound is selected from: Or its tautomers, stereoisomers or pharmaceutically acceptable salts.

13. The compound according to any one of claims 1-12, wherein the R 21 The methyl group is optionally replaced by one, two or three deuterium atoms, and the preferred compound is C-52 in Table 1.

14. The compound according to any one of claims 1-13, wherein the 1,3-thiazole of formula I is derived to thiazol-3(2H)-yl)methyl dihydrophosphate, preferably the compound is C-53 in Table 1.

15. A pharmaceutical composition comprising a compound or a tautomer, stereoisomer or pharmaceutically acceptable salt thereof according to any one of claims 1-14, and at least one pharmaceutically acceptable carrier.

16. A method of treating a disease characterized by overexpression of Polθ, comprising administering to a patient a therapeutically effective amount of the compound or its tautomer, stereoisomer or pharmaceutically acceptable salt, as described in any one of claims 1 to 14, or the pharmaceutical composition as described in claim 15; or The compound or its tautomer, stereoisomer or pharmaceutically acceptable salt according to any one of claims 1 to 14, or the pharmaceutical composition according to claim 15, is used as a medicament for treating a disease characterized by overexpression of Polθ. or Use of the compound or its tautomer, stereoisomer or pharmaceutically acceptable salt according to any one of claims 1 to 14, or the pharmaceutical composition according to claim 15, in the preparation of a medicament for treating a disease characterized by overexpression of Polθ.

17. The method, compound, or use of claim 16, wherein the patient is identified as needing this treatment and the disease is cancer.

18. The method, compound, or use of claim 16, wherein the cancer is a homologous recombination (HR) defective cancer.

19. The method, compound, or use of claim 16, wherein the cancer is characterized by reduced or absent BRCA gene expression, absence of the BRAC gene, or reduced BRCA protein function.

20. The method of any one of claims 17-19, wherein the cancer is lymphoma, soft tissue cancer, rhabdomyosarcoma, multiple myeloma, uterine cancer, gastric cancer, peripheral nervous system cancer, rhabdomyosarcoma, bone cancer, colorectal cancer, mesothelioma, breast cancer, ovarian cancer, lung cancer, fibroblastic cancer, central nervous system cancer, urinary system cancer, upper respiratory and digestive tract cancer, leukemia, kidney cancer, skin cancer, esophageal cancer, and pancreatic cancer.

Images