Pim kinase inhibitors

Abstract

The application provides a compound with a structure shown in a general formula (I), a deuterium compound, a stereoisomer or a pharmaceutically acceptable salt thereof, a pharmaceutical composition containing the same and a use thereof. The compound provided by the application has a good PIM kinase inhibition effect, is a novel, high-activity and low-toxicity ideal PIM inhibitor, and can be used for treating and / or preventing diseases such as acute myeloid leukemia, myelofibrosis, chronic lymphocytic leukemia, blood tumors such as gastric cancer and prostate cancer, and solid tumors.

Description

Technical Field

[0001] This invention belongs to the field of medicinal chemistry and relates to a PIM kinase inhibitor, its pharmaceutical composition, preparation method, and its use in the preparation, prevention, and / or treatment of indications related to the PIM signaling pathway. Background Technology

[0002] Moloney's murine leukemia virus proviral integration site (PIM) kinase is a serine / threonine protein kinase composed of three isoforms: PIM1, PIM2, and PIM3. PIM1 and PIM2 are highly expressed in hematologic malignancies and solid tumors, while PIM3 is highly expressed in hepatocellular carcinoma, pancreatic cancer, and colon cancer.

[0003] PIM kinase is a downstream molecule of the JAK / STAT pathway, which plays a crucial role in autoimmune diseases. Literature studies have shown that PIM-1 inhibitors are effective in a mouse model of inflammatory bowel disease, suggesting the potential application of PIM kinase inhibitors in autoimmune diseases.

[0004] Furthermore, PIM kinase can regulate cell proliferation, growth, and invasiveness by phosphorylating a series of downstream signaling molecules such as p53, BAD, and MYC, playing an important role in tumor development and progression. Preclinical studies have found that PIM inhibitors are effective against hematologic malignancies such as acute myeloid leukemia, myelofibrosis, and chronic lymphocytic leukemia, as well as solid tumors such as gastric cancer and prostate cancer, suggesting the role of PIM inhibitors in cancer treatment.

[0005] Sumitomo Pharma in Japan has developed a PIM inhibitor, TP-3654 (WO2013013188), but it exhibits low cell-inhibiting activity, significant toxicity, and low bioavailability. Therefore, there is an urgent need to provide a more effective PIM inhibitor. Summary of the Invention

[0006] To address the aforementioned technical problems, a first aspect of the present invention provides a compound having the structure shown in general formula (I), its deuterated derivative, stereoisomer, or pharmaceutically acceptable salt:

[0007]

[0008] Wherein, ring A is a 5-6 membered heterocyclic group, a 5-6 membered aryl group, or a 5-6 membered heteroaryl group; the 5-6 membered heterocyclic group or the 5-6 membered heteroaryl group contains at least one heteroatom selected from N, O, or S;

[0009] X is CH or N;

[0010] L represents a chemical bond or a methylene group;

[0011] R1 is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), halogen-substituted -C1-C6 alkyl, halogen-substituted -O(C1-C6 alkyl), -NH(C1-C6 alkyl), -N(C1-C6 alkyl)2, methanesulfonyl, or 5-6-membered heteroaryl; and when R1 is 5-6-membered heteroaryl, it is optionally surrounded by 0-3 R groups. b replace;

[0012] R2 is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy, or -COOR. c ;

[0013] R3 is selected from 3-10 saturated or unsaturated hydrocarbon groups (including straight-chain or branched alkyl or heteroalkyl groups), monocyclic or bicyclic cycloalkyl or heterocyclic groups, or monocyclic or bicyclic aryl or heteroaryl groups; wherein the heteroalkyl, heterocyclic, or heteroaryl group contains at least one heteroatom selected from N, O, or S.

[0014] The R3 is optionally divided by 1-3 Rs a replace;

[0015] The R a Selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -C3-C6 cycloalkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy or -(C1-C6 alkylene)-OH;

[0016] R b R c Each is independently selected from halogens or -C1-C3 alkyl groups.

[0017] In certain embodiments of the present invention, the compounds, deuterated derivatives, stereoisomers, or pharmaceutically acceptable salts having the structure shown in general formula (I) provided by the present invention may further be:

[0018] Ring A is a 5-6 membered aryl or a 5-6 membered heteroaryl; the 5-6 membered heteroaryl contains at least one heteroatom selected from N, O, and S;

[0019] X is CH or N;

[0020] L represents a chemical bond or a methylene group;

[0021] R1 is selected from hydrogen, halogen, hydroxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl or trifluoromethyloxy;

[0022] R2 is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl or trifluoromethyloxy;

[0023] R3 is selected from straight-chain or branched alkyl or heteroalkyl groups, monocyclic or bicyclic cycloalkyl or heterocyclic groups, or monocyclic or bicyclic aryl or heteroaryl groups; wherein the heteroalkyl, heterocyclic, or heteroaryl group contains at least one heteroatom selected from N, O, or S;

[0024] The R3 is optionally divided by 1-3 Rs a replace;

[0025] The R a It is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy or -(C1-C6 alkylene)-OH.

[0026] In certain embodiments of the present invention, the compounds, deuterated derivatives, stereoisomers, or pharmaceutically acceptable salts having the structure shown in general formula (I) provided by the present invention may further be:

[0027] Ring A is a phenyl or a 5-6-membered heteroaryl group, wherein the 5-6-membered heteroaryl group contains one heteroatom selected from N, O, and S;

[0028] X is an N atom;

[0029] L represents a chemical bond or a methylene group;

[0030] R1 is selected from hydrogen, trifluoromethyl, or trifluoromethyloxy;

[0031] R2 is selected from hydrogen;

[0032] R3 is selected from cycloalkyl or heterocyclic groups of 3-10 member monocyclic or bicyclic forms, wherein the heterocyclic group contains at least one heteroatom selected from N, O, or S;

[0033] The R3 is optionally divided by 1-3 Rs a replace;

[0034] The R a It is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy or -(C1-C6 alkylene)-OH.

[0035] In some embodiments of the present invention, the compounds provided by the present invention further have the structure shown in general formula (II):

[0036]

[0037] in,

[0038] Ring A is a benzene ring or a 5-membered heteroaryl group, wherein the 5-membered heteroaryl group optionally contains 1-2 heteroatoms selected from N, O, and S;

[0039] L represents a chemical bond or a methylene group;

[0040] R1 is selected from hydrogen, halogen, hydroxyl, cyano, carboxyl, -NH2, -C1-C3 alkyl, -C1-C3 alkoxy, halogen-substituted -C1-C3 alkyl, halogen-substituted -C1-C3 alkoxy, or a 5-membered heteroaryl group containing one heteroatom selected from N, O, or S.

[0041] R3 is selected from 6-7 membered monocyclic cycloalkyl or heterocyclic groups, wherein the heterocyclic group optionally contains 0-1 heteroatom selected from N, O, and S; or

[0042] R3 is selected from cycloalkyl or heterocyclic groups of 8-9 membered bicyclic rings, wherein the heterocyclic group optionally contains 0-1 heteroatom selected from N, O, and S; the bicyclic ring is a spirocyclic or bridged ring;

[0043] The R3 is optionally divided by one R a replace;

[0044] The R a It is selected from hydrogen, halogen, hydroxyl, carboxyl, -C1-C6 alkyl, -C3-C8 cycloalkyl or -(C1-C6 alkylene)-OH.

[0045] In certain embodiments of the present invention, the compounds, deuterated derivatives, stereoisomers, or pharmaceutically acceptable salts having the structure shown in general formula (II) provided by the present invention may further be:

[0046] Ring A is selected from phenyl, thienyl, or thiazolyl; and ring A is substituted by R1.

[0047] R1 is selected from hydrogen, -C1-C3 alkyl groups substituted with 1-3 halogens, or a 5-membered heteroaryl group containing one heteroatom selected from N, O, or S.

[0048] In some preferred embodiments, ring A is selected from...

[0049] L represents a chemical bond or a methylene group;

[0050] R1 is selected from hydrogen, trifluoromethyl, or...

[0051] R3 is selected from

[0052] R3 is selected from cycloalkyl or heterocyclic groups of an 8-9 membered bicyclic ring, wherein the heterocyclic group optionally contains one heteroatom selected from N, O, or S, and the bicyclic ring is a spirocyclic or bridged ring, wherein R3 is optionally separated by one R a replace;

[0053] The R a It is selected from hydrogen, hydroxyl, -C1-C3 alkyl, -C3-C6 cycloalkyl or -(C1-C6 alkylene)-OH.

[0054] In some preferred embodiments, R3 is selected from...

[0055] In some preferred embodiments, the R a It is selected from hydrogen, hydroxyl, methyl, cyclopropyl, -methylene hydroxyl or -C(CH3)2-OH.

[0056] In certain embodiments of the present invention, the compounds, deuterated derivatives, stereoisomers, or pharmaceutically acceptable salts having the structure shown in general formula (II) provided by the present invention may further be:

[0057] Ring A is selected from

[0058] L represents a chemical bond;

[0059] R1 is selected from hydrogen or trifluoromethyl;

[0060] R3 is selected from

[0061] R3 is selected from cycloalkyl or heterocyclic groups of an 8-9 membered bicyclic ring, wherein the heterocyclic group optionally contains one heteroatom selected from N, O, or S, and the bicyclic ring is a spirocyclic or bridged ring, wherein R3 is optionally separated by one R a replace;

[0062] The R a It is selected from hydrogen, hydroxyl, -C1-C3 alkyl, -C3-C6 cycloalkyl or -(C1-C6 alkylene)-OH.

[0063] In some preferred embodiments, R3 is selected from...

[0064] In some preferred embodiments, the R a It is selected from hydrogen, hydroxyl, methyl, cyclopropyl, -methylene hydroxyl or -C(CH3)2-OH.

[0065] In some preferred embodiments, R3 is selected from...

[0066] The R aSelected from hydrogen, hydroxyl, methyl, -methylene hydroxyl or -C(CH3)2-OH.

[0067] In some embodiments of the invention, the compounds provided by the invention further have the structure shown in general formula (III-1) or (III-2):

[0068]

[0069] R3 is selected from The R3 is optionally divided by one R a Substitution, with the substitution site being C or N;

[0070] The R a Selected from hydrogen, hydroxyl, -methylene hydroxyl or -C(CH3)2-OH.

[0071] In some preferred embodiments, R3 is selected from:

[0072]

[0073] In some preferred embodiments, R3 is selected from:

[0074]

[0075] In some preferred embodiments, R3 is selected from:

[0076]

[0077] In some embodiments of the present invention, the compound provided by the present invention further has a structure shown in general formula (III-1):

[0078]

[0079] R3 is selected from

[0080] In some embodiments of the present invention, the compounds provided by the present invention further have the structure shown in general formula (III-2):

[0081]

[0082] R3 is selected from

[0083] In some embodiments of the invention, the compounds provided by the invention further have the structure shown in general formula (IV-1) or (IV-2):

[0084]

[0085] Among them, ring A is selected from

[0086] R1 is selected from hydrogen or trifluoromethyl.

[0087] In some preferred embodiments, ring A is selected from...

[0088]

[0089] In certain embodiments of the present invention, the compounds with the structure shown in general formula (II) can also be summarized as follows:

[0090]

[0091] in,

[0092] Ring A is a phenyl or a 5-membered heteroaryl group, wherein the 5-membered heteroaryl group contains one or two heteroatoms optionally selected from N, O, and S; and ring A is substituted by R1;

[0093] L represents a chemical bond or a methylene group;

[0094] R1 is selected from hydrogen, halogen, hydroxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), -N(C1-C6 alkyl)2, trifluoromethyl or trifluoromethyloxy;

[0095] R3 is selected from cycloalkyl or heterocyclic groups of 3-10 member monocyclic or bicyclic forms, wherein the heterocyclic group contains one or two heteroatoms optionally selected from N, O, and S;

[0096] The R3 is optionally divided by 1-3 Rs a replace;

[0097] The R a The group is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy, or -(C1-C6 alkylene)-OH. In some preferred embodiments, the compound with the structure shown in general formula (II) may further be:

[0098] Ring A is selected from phenyl, furanyl, thienyl, pyrroleyl, thiazolyl, or pyrazolyl; and ring A is substituted by R1;

[0099] L represents a chemical bond or a methylene group;

[0100] R1 is selected from hydrogen, halogen, hydroxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), -N(C1-C6 alkyl)2, trifluoromethyl or trifluoromethyloxy;

[0101] R3 is selected from 6-10 membered monocyclic or bicyclic cycloalkyl or heterocyclic groups, wherein the heterocyclic group contains one heteroatom optionally selected from N, O, or S; wherein R3 is optionally surrounded by 1-3 R atoms. a replace;

[0102] The R a It is selected from hydrogen, halogen, hydroxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl) or -(C1-C6 alkylene)-OH.

[0103] In some preferred embodiments, the compound with the structure shown in general formula (II) may further be:

[0104] Ring A is selected from And ring A is replaced by R1;

[0105] L represents a chemical bond or a methylene group;

[0106] R1 is selected from hydrogen or trifluoromethyl;

[0107] R3 is selected from

[0108] The R3 is optionally divided by 1-3 Rs a Substitution, with the substitution site being C or N;

[0109] The R a Selected from hydrogen, hydroxyl, carboxyl, -C1-C6 alkyl, or -(C1-C6 alkylene)-OH;

[0110] In some preferred embodiments, the compound with the structure shown in general formula (II) may be further preferred as follows:

[0111] Ring A is selected from And ring A is replaced by R1;

[0112] L represents a chemical bond or a methylene group;

[0113] R1 is selected from hydrogen or trifluoromethyl;

[0114] R3 is selected from

[0115] The R3 is optionally divided by 1-2 Rs a Substitution, with the substitution site being C or N;

[0116] The R a Selected from hydrogen, hydroxyl, carboxyl, -C1-C3 alkyl or -(C1-C3 alkylene)-OH; other variables are as defined in this invention.

[0117] In some more specific embodiments, when the R3 group contains a heteroatom N, the substitution site is preferably at the N position. When the R3 group does not contain a heteroatom or the heteroatom is O, the substitution site is preferably at the meta or para position of the R3 group and the L linking site. When the R3 group has a bridged ring structure, the substitution site is usually on the bridgehead carbon at the other end of the L linking site.

[0118] In some more specific implementations, R a The group can be hydrogen, in which case it can also be considered unsubstituted.

[0119] In some more specific implementations, R a When the group is not hydrogen, it can be hydroxyl, carboxyl, -C1-C3 alkyl, or -(C1-C3 alkylene)-OH. Unless otherwise specified, -C1-C3 alkyl can be methyl, ethyl, n-propyl, isopropyl, or cyclopropyl. Unless otherwise specified, -(C1-C3 alkylene)-OH is methylene hydroxyl, ethylene hydroxyl, ...

[0120] Preferably, ring A is phenyl, pyridyl, tetrahydropyranyl, or pyrazolyl;

[0121] L represents a chemical bond or a methylene group;

[0122] R1 is selected from hydrogen, trifluoromethyl, or trifluoromethyloxy;

[0123] R2 is selected from hydrogen, methyl, halogen, carboxyl or cyano;

[0124] R3 is selected from monocyclic or bicyclic cycloalkyl or heterocyclic groups, or monocyclic or bicyclic aryl or heteroaryl groups; the heterocyclic or heteroaryl group contains at least one heteroatom selected from N, O, or S; R3 is optionally surrounded by 1-3 R atoms. a replace;

[0125] The R a Selected from methyl, isopropyl, carboxyl or 2-hydroxyisopropyl

[0126] As a preferred option: Ring A is selected from...

[0127] R3 is selected from

[0128] The R a Selected from methyl, isopropyl, carboxyl or 2-hydroxyisopropyl.

[0129] As a preferred option: R3 is selected from

[0130] In some embodiments of the present invention, the compounds provided by the present invention include any one of the following:

[0131]

[0132]

[0133]

[0134] A second aspect of the present invention provides a method for preparing a compound with the structure shown in general formula (II), comprising the following preparation process:

[0135]

[0136] In this compound, Z is H or I, M is a halogen or borate group, and the definitions of other groups are consistent with those of the compound shown in general formula (II). Intermediate 1 reacts with compound R1-AM to obtain intermediate 2, and then reacts with R3-L-NH2 to obtain the compound with the structure shown in general formula (II).

[0137] In some preferred embodiments, the Z atom in intermediate 1 can be H. When Z is H, M is a halogen. In this case, intermediate 1 undergoes a Heck coupling reaction with R1-AM to obtain intermediate 2. In other preferred embodiments, the Z atom in intermediate 1 can be I. When Z is I, M is a borate group. In this case, intermediate 1 undergoes a Suzuki coupling reaction with R1-AM to obtain intermediate 2.

[0138] In some preferred embodiments, intermediate 2 undergoes a nucleophilic substitution reaction with R3-L-NH2 to yield a compound with the structure shown in general formula (II). In other preferred embodiments, intermediate 2 undergoes a Buchwald-Hartwig coupling reaction with R3-L-NH2 to yield a compound with the structure shown in general formula (II).

[0139] A third aspect of the present invention provides a pharmaceutical composition comprising a compound, a deuterated form thereof, a stereoisomer thereof or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier thereof, according to any one of the foregoing technical solutions.

[0140] A fourth aspect of the invention provides the use of the compounds, deuterated derivatives, stereoisomers, or pharmaceutically acceptable salts described in any of the foregoing technical solutions, or the pharmaceutical compositions described in any of the foregoing technical solutions, in the preparation of medicaments for treating and / or preventing PIM-related diseases.

[0141] In some preferred embodiments, the PIM-related diseases include autoimmune diseases or tumors.

[0142] In some preferred embodiments, the PIM-related diseases include inflammatory bowel disease, hematologic malignancy, or solid tumor;

[0143] In some further preferred embodiments, the hematologic malignancies include, but are not limited to, acute myeloid leukemia, myelofibrosis, and chronic lymphocytic leukemia; the solid tumors include, but are not limited to, gastric cancer and prostate cancer.

[0144] The fifth aspect of the invention provides the use of the compounds, deuterated derivatives, stereoisomers, or pharmaceutically acceptable salts described in any of the foregoing technical solutions, or the pharmaceutical compositions described in any of the foregoing technical solutions, as PIM kinase inhibitors.

[0145] In some preferred embodiments, the PIM kinase inhibitor is used to treat and / or prevent PIM-related diseases, such as autoimmune diseases or tumors.

[0146] In some preferred embodiments, the PIM-related diseases include inflammatory bowel disease, hematologic malignancy, or solid tumor;

[0147] In some further preferred embodiments, the hematologic malignancies include, but are not limited to, acute myeloid leukemia, myelofibrosis, and chronic lymphocytic leukemia; the solid tumors include, but are not limited to, gastric cancer and prostate cancer.

[0148] The compound provided by this invention has a good PIM kinase inhibitory effect. Compared with the PIM inhibitor TP-3654, it has stronger cell inhibitory activity, lower toxicity and side effects, and has strong efficacy, good pharmacokinetic properties and high bioavailability. It is a novel, highly active and low-toxicity ideal PIM inhibitor that can be used to treat and / or prevent diseases such as acute myeloid leukemia, myelofibrosis, chronic lymphocytic leukemia and other hematologic malignancies, gastric cancer, prostate cancer and other solid tumors. Detailed Implementation

[0149] definition

[0150] The numerical ranges used in this article include the endpoints and any values ​​in between. For example, "0-3" can include 0, 1, 2, or 3, and "1-3" can include 1, 2, or 3.

[0151] The "C1-C" used in this article n "Including C1-C2, C1-C3, ... C1-C nFor example, a "C1-C6" group refers to a moiety containing 1 to 6 carbon atoms, meaning the group contains 1, 2, 3, 4, 5, or 6 carbon atoms. Therefore, for example, "C1-C4 alkyl" refers to an alkyl group containing 1 to 4 carbon atoms, where the alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl. Numerical ranges in this document, such as "1-6," refer to integers within a given range.

[0152] The term "alkyl" as used alone or in combination herein refers to a saturated aliphatic hydrocarbon that is optionally substituted with a straight chain or optionally substituted with a branched chain. "alkyl" as used herein preferably has 1-6 carbon atoms, for example, 1-5 carbon atoms, 1-4 carbon atoms, or 1-3 carbon atoms. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, 2-methyl-1-propyl, 2-methyl-2-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-3-butyl, 2,2-dimethyl-1-propyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2,2-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, etc. In this document, when the term "alkyl" is used in a numerical range, such as "C1-C6 alkyl," it refers to an alkyl group that can be composed of 1, 2, 3, 4, 5, or 6 carbon atoms. The term alkyl in this document also includes cases where no numerical range is specified. Alkyl groups can be optionally substituted or unsubstituted.

[0153] The term “alkyl” as used in this article refers to an alkyl group linked to other groups, such as an alkyl group in an alkoxy group, and is defined the same as when used alone.

[0154] The term "alkylene" as used alone or in combination herein refers to a saturated aliphatic divalent hydrocarbon group obtained by removing two hydrogen atoms from a straight-chain or branched saturated aliphatic hydrocarbon group. The "alkylene" herein preferably has 1-6 carbon atoms, for example, 1-5 carbon atoms, 1-4 carbon atoms, or 1-3 carbon atoms. Non-limiting examples of alkylene include -CH2- (i.e., methylene), -CH2-CH2- (i.e., ethylene), -CH2-CH2-CH2-, -CH(CH3)CH2-, -C(CH3)2-, -CH2-C(CH3)-CH2-, -CH2-CH2-CH2-CH2-, -CH2-C(CH3)-CH2-CH2-, -CH2-CH2-CH2-CH2-CH2-, -CH2-CH2-CH2-CH2-CH2-, etc. Alkylenes may be optionally substituted or unsubstituted.

[0155] The term “heteroalkyl” as used alone or in combination herein refers to a group in which a carbon atom in an alkyl group is replaced by one or more heteroatoms selected from nitrogen, oxygen, and sulfur, wherein the definition of alkyl is the same as the definition of “alkyl” above.

[0156] The term "alkoxy" as used alone or in combination herein is meant as "alkyl-O-". Non-limiting examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, etc. Alkoxy groups may be optionally substituted or unsubstituted.

[0157] The term "cycloalkyl" as used alone or in combination herein refers to saturated monocyclic, bicyclic, fused, bridged, spirocyclic, and other carbon rings. C3-C is preferred in this document. 12 Cycloalkyl, more preferably C3-C 10 Cycloalkyl, most preferably C3-C8 cycloalkyl. Non-limiting examples of monocyclic cycloalkyl include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, etc., which may be optionally substituted or unsubstituted.

[0158] In the definition of "cycloalkyl", "spirocyclic" refers to a polycyclic group consisting of two or more ring structures, where each ring shares a carbon atom (called a spiro atom). Preferably, it consists of 6 to 12 nucleotides, more preferably 8 to 9 nucleotides. Based on the number of shared spiro atoms between rings, spirocyclic groups are classified as monospiro, bispiro, or polyspirocyclic alkyl groups. Preferably, they are monospiro and bispirocyclic alkyl groups, and more preferably 4 / 5, 4 / 6, 5 / 5, or 5 / 6 spirocyclic alkyl groups.

[0159] In the definition of "cycloalkyl", "fused ring" refers to a polycyclic aromatic hydrocarbon group containing two or more ring structures that share a pair of carbon atoms. Preferably, it is a 6- to 12-membered group, more preferably an 8- to 9-membered group. Depending on the number of rings, it can be classified as bicyclic, tricyclic, tetracyclic, or polycyclic fused cycloalkyl. Preferably, it is a bicyclic or tricyclic group, more preferably a 5-membered / 5-membered, 5-membered / 6-membered, or 6-membered / 6-membered bicyclic alkyl group.

[0160] In the definition of "cycloalkyl", "bridged ring" refers to a polycyclic aromatic hydrocarbon group containing two or more ring structures that share two carbon atoms that are not directly connected. Preferably, it consists of 6 to 12 rings, more preferably 8 to 9 rings. Based on the number of rings, it can be classified as bicyclic, tricyclic, tetracyclic, or polycyclic bridged cycloalkyl groups, with bicyclic or tricyclic being preferred.

[0161] The term "heteroaryl" as used alone or in combination herein refers to a 5- to 12-membered (preferably 5- to 10-membered, more preferably 5- to 6-membered) monocyclic, bicyclic, or tricyclic system, wherein at least one ring is aromatic and at least one ring contains one or more heteroatoms selected from nitrogen, oxygen, and sulfur, and the heteroaryl group has one or more attachment sites connected to the remainder of the molecule. Non-limiting examples of "heteroaryl" include furanyl, imidazolyl, isoxazolyl, oxazolyl, pyrroleyl, pyrazolyl, pyridinyl, pyrimidinyl, pyridazinyl, thiophene, thiazolyl, etc.; it also includes, but is not limited to, the following bicyclic groups: benzimidazolyl, benzofuranyl, benzothiophene, indolyl, oxoindolyl, dihydroindolyl, imidazopyridyl, pyrazolopyridyl, pyrazolopyrimidinyl, quinolinyl, isoquinolinyl, quinazolinyl, etc. Heteroaryl groups may be optionally substituted or unsubstituted.

[0162] The term "heterocyclic group" as used alone or in combination herein includes alicyclic and aromatic heterocyclic groups, wherein one or more cyclic atoms are heteroatoms, such as oxygen, nitrogen, sulfur, etc., including monocyclic, fused, bridged, and spirocyclic groups. Preferably, heterocyclic groups are 3- to 10-membered monocyclic, bicyclic, or tricyclic groups, which may contain one, two, or three ring atoms selected from nitrogen, oxygen, and / or sulfur. Non-limiting examples of "heterocyclic group" include morpholinyl, oxobutyryl, thiomorpholinyl, tetrahydropyranyl, 1,1-dioxo-thiomorpholinyl, piperidinyl, 2-oxo-piperidinyl, pyrrolyl, 2-oxo-pyrrolyl, piperazine-2-one, 8-oxa-3-aza-bicyclo[3.2.1]octyl, piperazine, etc. Heterocyclic groups may be optionally substituted or unsubstituted.

[0163] In the definition of "heterocyclic group", "spirocyclic" refers to a polycyclic group with two or more ring structures in which the single rings share an atom with each other, containing one or more double bonds in the rings, but none of the rings have fully conjugated π electrons, and one or more ring atoms are selected from nitrogen, oxygen or S(O). n(where n is selected from 0, 1, or 2) heteroatoms, and the remaining ring atoms are carbon. Preferably, they are 6 to 12-membered, and more preferably 8 to 9-membered. Spirocyclic rings are classified into monospirocyclic, bispirocyclic, or multispirocyclic groups according to the number of shared spiroatoms between rings, preferably monospirocyclic and bispirocyclic groups, and more preferably 4-membered / 4-membered, 4-membered / 5-membered, 4-membered / 6-membered, 5-membered / 5-membered, or 5-membered / 6-membered monospirocyclic groups.

[0164] In the definition of "heterocyclic group", "fused ring" refers to a polycyclic group containing two or more ring structures that share a pair of atoms with each other. One or more rings may contain one or more double bonds, but none of the rings have fully conjugated π electrons in an aromatic system. At the same time, at least one ring has fully conjugated π electrons in an aromatic system, wherein one or more ring atoms are selected from nitrogen, oxygen or S(O). n (where n is selected from 0, 1 or 2) heteroatoms, and the remaining ring atoms are carbon. Preferably, they are 6 to 12-membered, and more preferably 8 to 9-membered. Depending on the number of rings, they can be classified as bicyclic, tricyclic, tetracyclic or polycyclic fused heterocyclic groups, preferably bicyclic or tricyclic, and more preferably 5-membered / 5-membered or 5-membered / 6-membered bicyclic fused heterocyclic groups.

[0165] In the definition of "heterocyclic group", "bridged ring" refers to a polycyclic group containing two or more ring structures that share two atoms that are not directly connected to each other. One or more rings may contain one or more double bonds, but none of the rings have fully conjugated π electrons. One or more ring atoms are selected from nitrogen, oxygen or S(O). n (where n is selected from 0, 1, or 2) heteroatoms, and the remaining ring atoms are carbon. Preferably, it consists of 6 to 12 rings, more preferably 8 to 9 rings. Depending on the number of rings, it can be classified as a bicyclic, tricyclic, tetracyclic, or polycyclic bridged heterocyclic group, with bicyclic or tricyclic rings being preferred.

[0166] The term “halogen” as used alone or in combination in this article refers to fluorine, chlorine, bromine or iodine.

[0167] The term "hydroxyl group" as used alone or in combination in this article refers to -OH.

[0168] The term "cyano" as used alone or in combination in this article refers to -CN.

[0169] The term "methanesulfonyl" as used alone or in combination in this article refers to -S(O)2-CH3.

[0170] As used herein, the terms “(substituted)” or “substituted with” refer to the substitution of one or more hydrogen atoms on a particular atom by a specified group (such as halogen, alkyl, etc.) where the substitution results in a stable compound if the normal valence of the specified atom is not exceeded under the present circumstances.

[0171] The term “pharmaceutically acceptable salt” as used herein is well known to those skilled in the art.

[0172] As used herein, the term "pharmaceutically acceptable" means a substance (such as a carrier or diluent) that does not affect the biological activity or properties of the compounds of the present invention and is relatively non-toxic, i.e., that the substance can be administered to an individual without causing an adverse biological reaction or interacting adversely with any component contained in the composition.

[0173] As used herein, the term "pharmaceutical composition" refers to a bioactive compound optionally mixed with at least one pharmaceutically acceptable chemical component, including but not limited to carriers, stabilizers, diluents, dispersants, suspending agents, thickeners, and / or excipients.

[0174] As used in this article, the term "carrier" refers to a relatively non-toxic chemical compound or reagent that facilitates the introduction of the compound into cells or tissues.

[0175] The term “stereoisomer” as used in this article includes, but is not limited to, enantiomers, cis-trans isomers, etc.

[0176] As used herein, the term "enantiomer" refers to isomerism in compounds with the same molecular formula, resulting from differences in the spatial arrangement of atoms or groups. Two enantiomers are mirror images of each other and cannot be superimposed. The term "cis-trans isomer" as used herein generally refers to stereoisomerism, a non-diasteretic phenomenon where the spatial arrangement of groups differs due to rotational constraints within the molecule. Organic molecules containing such isomers, such as alkenes, azo compounds, and alicyclic hydrocarbons, are considered cis-trans isomers. In this application, cis-trans isomerism is primarily manifested in alicyclic hydrocarbons. For example, in cyclohexane, cis-trans isomerism occurs when two substituents are substituted. When the two substituents are substituted on the same side of the ring, it is a "cis" isomer; when they are substituted on different sides, it is a "trans" isomer.

[0177] The compounds of this invention may contain asymmetric or chiral centers, and thus exist in different stereoisomer forms. It is contemplated that all stereoisomer forms of the compounds of this invention, including but not limited to diastereomers, enantiomers, sterically hindered isomers, and geometric (conformal) isomers and mixtures thereof, such as racemic mixtures, are within the scope of this invention.

[0178] Unless otherwise stated, the structures described in this invention also include all isomers of this structure (e.g., diastereomers, enantiomers, cis-trans isomers, sterically hindered isomers, geometric (conformal) isomers), for example, R and S configurations of each asymmetric center, (Z) and (E) double bond isomers, cis-trans isomers of aliphatic cyclic hydrocarbons, sterically hindered isomers of biphenyl structures (see *Basic Organic Chemistry* (Second Edition), Vol. 1, Xing Qiyi et al., pp. 104-105); PAC, 1996, 68, 2193. (*Basic terminology of stereochemistry* (IUPAC Recommendations 1996, on page 2201)), and (Z) and (E) conformational isomers. Therefore, individual stereoisomers of the compounds of this invention, as well as mixtures of enantiomers, mixtures of diastereomers, sterically hindered isomers, and mixtures of geometric (conformal) isomers, are all within the scope of this invention.

[0179] In the following examples, all the compounds prepared have the structure shown in general formula (I):

[0180]

[0181] Wherein, ring A is a 5-6 membered aryl or a 5-6 membered heteroaryl; the 5-6 membered heteroaryl contains at least one heteroatom selected from N, O, and S;

[0182] X is a C or N atom;

[0183] L represents a chemical bond or a methylene group;

[0184] R1 is selected from hydrogen, halogen, hydroxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl or trifluoromethyloxy;

[0185] R2 is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl or trifluoromethyloxy;

[0186] R3 is selected from 3-10 saturated or unsaturated hydrocarbon groups (including straight-chain, branched alkyl or heteroalkyl groups), monocyclic or bicyclic cycloalkyl or heterocyclic alkyl groups, monocyclic or bicyclic aryl or heteroaryl groups; the heteroalkyl, heterocyclic, or heteroaryl group contains at least one heteroatom selected from N, O, or S; R3 is optionally surrounded by 1-3 R groups. a replace;

[0187] The R aIt is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy or -(C1-C6 alkylene)-OH.

[0188] Some of these compounds also conform to the structure shown in general formula (II):

[0189]

[0190] Wherein, ring A is a phenyl or a 5-membered heteroaryl group, wherein the 5-membered heteroaryl group contains one or two heteroatoms optionally selected from N, O, and S; and ring A is substituted by R1;

[0191] L represents a chemical bond or a methylene group;

[0192] R1 is selected from hydrogen, halogen, hydroxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), -N(C1-C6 alkyl)2, trifluoromethyl or trifluoromethyloxy;

[0193] R3 is selected from 3-10 membered monocyclic or bicyclic cycloalkyl or heterocyclic groups, wherein the heterocyclic group contains one or two heteroatoms optionally selected from N, O, or S; wherein R3 is optionally surrounded by 1-3 R atoms. a replace;

[0194] The R a It is selected from hydrogen, halogen, hydroxyl, carboxyl, cyano, -NH2, -C1-C6 alkyl, -O(C1-C6 alkyl), -NH(C1-C6 alkyl), trifluoromethyl, trifluoromethyloxy or -(C1-C6 alkylene)-OH.

[0195] For compounds with the structure shown in general formula (II), the following methods can usually be used for synthesis.

[0196]

[0197] Where Z is H or I, M is a halogen or borate group, and the definitions of other groups are consistent with those of the compound shown in general formula (II). Intermediate 1 reacts with compound R1-AM to obtain intermediate 2, and then reacts with R3-L-NH2 to obtain the compound with the structure shown in general formula II.

[0198] Step 1: Synthesis of intermediate 2.

[0199] When the Z atom of intermediate 1 is H, then M is a halogen. In this case, intermediate 1 undergoes a Heck coupling reaction with R1-AX to give intermediate 2. The specific reaction conditions are as follows:

[0200]

[0201] Under nitrogen protection at room temperature, R1-AX is added sequentially to the intermediate 1 solution, followed by the Pd catalyst, support, and base. The reaction is carried out at a temperature above room temperature, and the reaction is monitored by methods such as TLC or LCMS until the reaction is complete, yielding intermediate 2. The solvent, Pd catalyst, support, and base can be selected from common Heck reaction systems. In some specific embodiments, the solvent can be toluene, DMF, NMP, etc. In some specific embodiments, the Pd catalyst can be palladium chloride, palladium acetate, tetraphenylphosphine palladium, and under certain special conditions, copper catalysts such as cuprous iodide can also be used. In some specific embodiments, the support can be triphenylphosphine, BINAP, etc. In some specific embodiments, the base can be triethylamine, potassium carbonate, sodium acetate, potassium acetate. The reaction temperature is above room temperature, or it can be the reflux temperature of the solvent, or slightly below the reflux temperature, specifically any temperature between 20-120°C.

[0202] When the Z atom in intermediate 1 is I, then M is a borate group. In this case, intermediate 1 undergoes a Suzuki coupling reaction with R1-AM to give intermediate 2. The specific reaction conditions are as follows:

[0203]

[0204] Under nitrogen protection at room temperature, R1-AB(OH)2 is added sequentially to the intermediate 1 solution, followed by the Pd catalyst, support, and base. The reaction is carried out at a temperature above room temperature, and the reaction is monitored by methods such as TLC or LCMS until the reaction is complete, yielding intermediate 2. The solvent, Pd catalyst, support, and base can be selected from common Suzuki reaction systems. In some specific embodiments, the solvent can be toluene, dioxane, water, or a combination thereof. In some specific embodiments, the Pd catalyst can be palladium chloride, Pd / C, palladium acetate, tetraphenylphosphine palladium, or Pd2(dba)3; under certain special conditions, a nickel catalyst can also be used. In some specific embodiments, the support can be triphenylphosphine, BINAP, or PCy3. In some specific embodiments, the base can be potassium carbonate, sodium carbonate, cesium carbonate, or lithium carbonate. The reaction temperature is above room temperature, or it can be the reflux temperature of the solvent, or slightly below the reflux temperature, specifically any temperature between 80-110°C.

[0205] Step 2: Synthesis of compounds with the structure shown in general formula (II).

[0206] For some compounds, nucleophilic substitution reactions are suitable, and the specific reaction conditions are as follows:

[0207]

[0208] At room temperature, R3-L-NH2 and a base are added sequentially to a dimethyl sulfoxide solution of intermediate 2, followed by heating and monitoring the reaction by TLC or LCMS until complete, yielding a compound with the structure shown in general formula (II). In some specific embodiments, the base may be cesium fluoride, potassium fluoride, cesium fluoride, and N,N-diisopropylethylamine or combinations thereof, or no base may be added. In some specific embodiments, the reaction temperature is typically above room temperature, specifically any value between 100 and 140 °C.

[0209] For another group of compounds, the Buchwald-Hartwig coupling reaction is more suitable, and the specific reaction conditions are as follows:

[0210]

[0211] Under nitrogen protection at room temperature, R3-L-NH2 is added sequentially to the intermediate 2 solution, followed by the catalyst, support, and base. The reaction is carried out at a temperature above room temperature, and the reaction is monitored by methods such as TLC or LCMS until the reaction is complete, yielding the compound with the structure shown in general formula (II). The solvent, Pd catalyst, support, and base can be selected from common Buchwald-Hartwig reaction systems. In some specific embodiments, the solvent can be toluene, dioxane, water, or a combination thereof. In some specific embodiments, the catalyst can be palladium acetate or Pd2(dba)3. In some specific embodiments, the support can be P(t-Bu)3, BINAP, P(o-tolyl)3, or Xantphos. In some specific embodiments, the base can be cesium carbonate, potassium tert-butoxide, or sodium tert-butoxide. The reaction temperature is above room temperature, or the reflux temperature of the solvent can be selected, or slightly below the reflux temperature, specifically any temperature between 80-110°C.

[0212] The present invention will be further described in detail below with reference to specific embodiments, but the present invention is not limited to the following embodiments.

[0213] The preparation conditions used in the examples are as follows:

[0214] Pre-HPLC preparation conditions: Instrument: GILSON-GX281; Wavelength: 220nm & 254nm; Column type: Waters X-bridge (30×100mm, 10μm) or Luna C18 (30×75mm, 3μm) or Luna C18 (30×75mm, 3μm); Mobile phase: A: 10mM ammonium bicarbonate or H2O (0.1% formic acid) or H2O (0.1% trifluoroacetic acid), B: acetonitrile; Run time: 15min; Flow rate: 25mL / min.

[0215] Reverse column purification was performed using a C18 reverse silica column (Spherical C18, 40-60 μm, 40 g-120 g) with water / acetonitrile (95 / 5 to 30 / 70) as the mobile phase.

[0216] Example 1: 6-(((1-methylpiperidin-4-yl)methyl)amino)-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid (compound 6)

[0217]

[0218] (1) Ethyl 3-bromo-6-chloroimidozono[1,2-b]pyridazine-2-carboxylic acid ester

[0219] Ethyl 6-chloroimidazolo[1,2-b]pyridazine-2-carboxylate (1.0 g, 3.92 mmol) was dissolved in dichloromethane (15 mL), and NBS (1.1 g, 5.88 mmol) was added. The reaction mixture was stirred overnight at room temperature. Water was added to the reaction solution, and the mixture was extracted with dichloromethane. The organic phase was washed with saturated brine (10 mL), dried over anhydrous sodium sulfate, concentrated under reduced pressure, and the crude product was purified by reverse-phase column chromatography to give ethyl 3-bromo-6-chloroimidazolo[1,2-b]pyridazine-2-carboxylate (310 mg, yield: 24%), a yellow solid. MS (ESI): m / z 305.8 [M+H] + .

[0220] (2) Ethyl 6-chloro-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid ester

[0221] Under nitrogen atmosphere, tetraphenylphosphine palladium (185 mg, 0.16 mmol) was added to a mixed solution (5:1, 12 mL) of ethyl 3-bromo-6-chloroimidozolo[1,2-b]pyridazine-2-carboxylate (500 mg, 1.64 mmol), (3-(trifluoromethoxy)phenyl)boronic acid (185 mg, 0.16 mmol), and potassium carbonate (375 mg, 4.94 mmol) in dioxane and water. The reaction mixture was heated to 90 °C and stirred overnight. The reaction mixture was then concentrated under reduced pressure. The crude product was purified using a reverse-phase column chromatography to give ethyl 6-chloro-3-(3-(trifluoromethoxy)phenyl)imidozolo[1,2-b]pyridazine-2-carboxylate (310 mg, yield: 49%), a yellow solid. MS (ESI): m / z 385.9 [M+H] + .

[0222] (3) 6-(((1-methylpiperidin-4-yl)methyl)amino)-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid

[0223] Ethyl 6-chloro-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid (100 mg, 0.26 mmol) was dissolved in toluene (5 mL), followed by the addition of sodium tert-butoxide (75 mg, 0.78 mmol), BINAP (23 mg, 0.05 mmol), tris(dibenzylacetone)dipalladium (27 mg, 0.03 mmol), and (1-methylpiperidin-4-yl)methylamine (66 mg, 0.52 mmol). The mixture was purged with nitrogen and reacted overnight at 100 °C. The reaction solution was filtered, and the filtrate was concentrated to dryness and purified directly using a reverse-phase column to obtain the crude product. The crude product was purified by Prep-HPLC to obtain 6-(((1-methylpiperidin-4-yl)methyl)amino)-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid (8.5 mg, yield: 7%), a white solid. MS(ESI): m / z 450.2 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ7.77-7.72(m,3H),7.55(t,J=8.4Hz,1H),7.38(d,J=8.4Hz,1H),7.28(t,J=5.6Hz,1H),6.82(d,J=9.6 Hz,1H),2.99(t,J=6.0Hz,2H),2.87-2.81(m,2H),2.23(s,3H),2.00(t,J=11.6Hz,2H),1.65-1.58(m,3H),1.24-1.18(m,2H).

[0224] Example 2: N-((1-methylpiperidin-4-yl)methyl)-3-(pyridin-3-yl)imidazolium[1,2-a]pyridine-6-amine (Compound 7)

[0225]

[0226] (1) 6-Chloro-3-(pyridin-3-yl)imidazo[1,2-a]pyridine

[0227] Following the method in step (2) of Example 1, 3-bromo-6-chloroimidazolo[1,2-a]pyridine (200 mg, 0.86 mmol) and pyridine-3-ylboronic acid (105 mg, 0.86 mmol) were used as starting materials to obtain the product 6-chloro-3-(pyridin-3-yl)imidazolo[1,2-a]pyridine (67 mg, yield: 34%), a yellow oily liquid. MS (ESI): m / z 230 [M+H] + .

[0228] (2) N-((1-methylpiperidin-4-yl)methyl)-3-(pyridin-3-yl)imidazol[1,2-a]pyridine-6-amine

[0229] Following the method in step (3) of Example 1, using 6-chloro-3-(pyridin-3-yl)imidazo[1,2-a]pyridine (67 mg, 0.29 mmol) and (1-methylpiperidin-4-yl)methylamine (37.6 mg, 0.29 mmol) as starting materials, N-((1-methylpiperidin-4-yl)methyl)-3-(pyridin-3-yl)imidazo[1,2-a]pyridine-6-amine (10.9 mg, yield: 11%) was obtained as a white solid. MS (ESI): m / z 323.2 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ9.37(s,1H),8.56(d,J=8.0Hz,1H),8.49(s,1H),8.06(s,1H),7.78(d,J=8.0Hz,1H),7.49-7.45(m,1H),7.20(t,J=6.4Hz,1 H),6.76(d,J=9.6Hz,1H),3.17(t,J=6.0Hz,2H),2.80(d,J=11.2Hz,2H),2 .14(s,3H),1.84(t,J=11.2Hz,2H),1.74-1.65(m,1H),1.29-1.20(m,2H).

[0230] Example 3: 1-Methyl-4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid (Compound 8)

[0231]

[0232] (1) 6-Chloro-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine

[0233] Following the method in step (2) of Example 1, 3-bromo-6-chloroimidazole[1,2-b]pyridazine (800 mg, 3.44 mmol) and (3-(trifluoromethoxy)phenyl)boronic acid (708.4 mg, 3.44 mmol) were used as starting materials to obtain the product 6-chloro-3-(3-(trifluoromethoxy)phenyl)imidazole[1,2-b]pyridazine (560.2 mg, yield: 52%), a yellow solid. MS (ESI): m / z 314.0 [M+H] + .

[0234] (2) 1-(tert-butoxycarbonyl)-4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid

[0235] Following the method in step (3) of Example 1, using 6-chloro-3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine (510 mg, 1.63 mmol) and 1-tert-butyl-4-ethyl 4-(aminomethyl)piperidine-1,4-dicarboxylic acid (466 mg, 1.63 mmol) as starting materials, 1-(tert-butoxycarbonyl)-4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazine-6-yl)amino)methyl)piperidine-4-carboxylic acid (240 mg, yield: 28%) was obtained as a white solid. MS (ESI): m / z 536.0 [M+H] + .

[0236] (3) 4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid

[0237] 1-(tert-butoxycarbonyl)-4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid (150 mg, 1.75 mmol) was dissolved in ethyl acetate (5 mL). Ethyl acetate hydrochloride (5 mL) was added to the reaction mixture, and the mixture was stirred at room temperature for 2 hours. The solution was concentrated under reduced pressure to give 4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid (122 mg, yield: 99%), a white solid. MS (ESI): m / z 436.0 [M+H] + .

[0238] (4) 1-Methyl-4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid

[0239] 4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid (122 mg, 0.28 mmol) was dissolved in methanol (5 mL), and 37% formaldehyde solution (113.5 mg, 1.4 mmol) and sodium cyanoborohydride (35.2 mg, 0.56 mmol) were added. The reaction mixture was stirred overnight at room temperature. The reaction solution was filtered and evaporated to dryness. The residue was purified by Pre-HPLC to give 1-methyl-4-(((3-(3-(trifluoromethoxy)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)methyl)piperidine-4-carboxylic acid (35.8 mg, yield: 29%), a white solid. MS (ESI): m / z 450.3 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.45(s,1H),8.19(s,1H),8.10(d,J=8.4Hz,1H),8.01(s,1H),7.77(d,J=10.0Hz,1H),7.56(t,J=8.0Hz 1H),7.29(d,J=8.0Hz,1H),7.02(s,1H),6.87(d,J=9.6Hz,1H),3.52(s,2H),2 .69(d,J=10.8Hz,2H),2.19(s,3H),2.16-2.09(m,4H),1.56(t,J=10.4Hz,2H).

[0240] Example 4: N-(1-isopropyl-1H-pyrazol-3-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-amine (Compound 10)

[0241]

[0242] (1) 1-Isopropyl-3-nitro-1H-pyrazole

[0243] 3-Nitro-1H-pyrazole (1050 mg, 9.2 mmol) and NaH (446 mg, 11.1 mmol) were dissolved in DMF (5 mL). The reaction mixture was stirred at 0 °C for 0.5 h. 2-Bromopropane (1250 mg, 10.2 mmol) was added to the reaction mixture, and the mixture was stirred overnight at room temperature. The reaction was quenched with a small amount of water. The mixture was extracted with ethyl acetate, and the organic phase was washed successively with saturated brine, dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and purified by reverse-phase column chromatography to obtain 1-isopropyl-3-nitro-1H-pyrazole[2,3-b]pyridine (320 mg, yield: 23%), a colorless oil. MS (ESI): m / z 156.1 [M+H] + .

[0244] (2) 1-Isopropyl-1H-pyrazole-3-amine

[0245] 1-Isopropyl-3-nitro-1H-pyrazole (200 mg, 1.2 mmol) and Pd / C (100 mg) were added to a methanol (4 mL) solution. The mixture was heated to 40 °C under hydrogen protection and stirred overnight. The reaction solution was filtered and evaporated to dryness to give 1-isopropyl-1H-pyrazole-3-amine (120 mg, yield: 74%), a colorless oil. MS (ESI): m / z 126.1 [M+H] + .

[0246] (3) 6-Chloro-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine

[0247] Following the method in step (2) of Example 1, 3-bromo-6-chloroimidazole[1,2-b]pyridazine (300 mg, 1.2 mmol) and (3-(trifluoromethyl)phenyl)boronic acid (246 mg, 1.2 mmol) were used as raw materials to obtain (6-chloro-3-(3-(trifluoromethyl)phenyl)imidazole[1,2-b]pyridazine (120 mg, yield: 31%), a yellow solid. MS (ESI): m / z 298.3 [M+H] + .

[0248] (4) N-(1-isopropyl-1H-pyrazol-3-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-amine

[0249] Following the method in step (3) of Example 1, using 6-chloro-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine (120 mg, 0.4 mmol) and 1-isopropyl-1H-pyrazole-3-amine (50 mg, 0.4 mmol) as starting materials, N-(1-isopropyl-1H-pyrazole-3-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-amine (15.8 mg, yield: 10%) was obtained as a white solid. MS (ESI): m / z 387.2 [M+H] + . 1 H NMR(400MHz, DMSO-d6)10.01(s,1H),8.58(s,1H),8.32-8.29(m,1H),8.04(s,1H),7.93(d,J=9.6Hz,1H), 7.75-7.70(m,2H),7.62(s,1H),7.03(d,J=9.6Hz,1H),6.54(s,1H),4.48-4.38(m,1H),1.42-1.40(m,6H).

[0250] Example 5: 2-((1r,4r)-4-((2-methyl-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)propanol (compound 11)

[0251]

[0252] (1) 3-Bromo-6-chloro-2-methylimidazo[1,2-b]pyridazine

[0253] 6-Chloro-2-methylimidazo[1,2-b]pyridazine (300 mg, 1.8 mmol) and NBS (350 mg, 1.9 mmol) were dissolved in dichloromethane (5 mL). The reaction mixture was reacted overnight at room temperature. The reaction solution was concentrated under reduced pressure and purified by silica gel column chromatography (PE:EA = 3:1) to obtain 3-bromo-6-chloro-2-methylimidazo[1,2-b]pyridazine (440 mg, yield: 100%), a white solid. MS (ESI): m / z 245.7 [M+H] + .

[0254] (2) 6-Chloro-2-methyl-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine

[0255] Following the method in step (2) of Example 1, 3-bromo-6-chloro-2-methylimidazo[1,2-b]pyridazine (450 mg, 1.8 mmol) and 3-(trifluoromethyl)phenyl)boronic acid (279 mg, 1.5 mmol) were used as raw materials to obtain 6-chloro-2-methyl-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine (110 mg, yield: 19%), a white solid. MS (ESI): m / z 311.9 [M+H] + .

[0256] (3)2-((1r,4r)-4-((2-methyl-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)propanol

[0257] Following the method in step (3) of Example 1, 6-chloro-2-methyl-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine (40 mg, 0.1 mmol) and 2-((1r,4r)-4-aminocyclohexyl)propanol (40 mg, 0.3 mmol) were used as starting materials to obtain 2-((1r,4r)-4-((2-methyl-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-yl)amino)cyclohexyl)propanol (23.8 mg, yield: 43%), a white solid. MS (ESI): m / z 433.4 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.35(s,1H),7.93(d,J=7.5Hz,1H),7.75–7.61(m,3H),6.83(d,J=7.3Hz,1H),6.65(d,J=9.6Hz ,1H),4.02(s,1H),3.54–3.37(m,1H),2.45(s,3H),2.09(d,J=10.1Hz,2H),1.81(d,J=12.0Hz,2H),1.27–0.95(m,11H).

[0258] Example 6: 2-[(1r,4r)-4-[[3-(2-thienyl)imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol (Compound 14)

[0259]

[0260] (1) 6-Chloro-3-(2-thienyl)imidazo[1,2-b]pyridazine

[0261] Following the method in step (2) of Example 1, 6-chloro-3-iodo-imidazo[1,2-b]pyridazine (0.05 g, 178.9 μmol) and 2-thiopheneboronic acid (27.47 mg, 214.7 μmol) were used as raw materials in six parallel batches to obtain 6-chloro-3-(2-thiophene)imidazo[1,2-b]pyridazine (0.2 g, yield: 79.05%), a yellow solid. 1 H NMR (400MHz, CDCl3) δ7.71-7.64(m,2H),7.61-7.52(m,2H),7.50-7.43(m,2H).

[0262] (2) 2-[4-[[3-(2-thienyl)imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol

[0263] At 20°C, 2-((1r,4r)-4-aminocyclohexyl)prop-2-ol (6.67 mg, 42.43 μmol), cesium fluoride (6.44 mg, 42.43 μmol), and N,N-diisopropylethylamine (5.48 mg, 42.43 μmol, 7.39 μL) were added sequentially to a dimethyl sulfoxide (0.05 mL) solvent containing 6-chloro-3-(2-thienyl)imidazo[1,2-b]pyridazine (0.005 g, 21.21 μmol). After the addition was complete, the reaction system was heated to 100°C and stirred for 12 hours. LC-MS showed that the starting material reacted completely and products were formed. The reaction solution was purified by Prep-HPLC to give 2-[(1r,4r)-4-[[3-(2-thienyl)imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol (0.002 g, yield: 26.45%), a yellow solid. MS (ESI): m / z 357.1 [M+H] + . 1 HNMR (400MHz, CDCl3) δ7.78(brs,1H),7.59(dd,J=1.1,3.7Hz,2H),7.30(d,J=5.3Hz,1H),7.08(dd,J=3.7,5.1Hz,1H),6.33(d, J=9.0Hz,1H),4.17(brs,1H),3.82-3.67(m,1H),2.36(d,J=11.0Hz,2H),1.92(d,J=9.4Hz,2H),1.37-1.18(m,5H),1.18(s,6H).

[0264] Example 7: N-(7-azaspiro[3.5]nonane-2-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (Compound 16)

[0265]

[0266] (1) 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester

[0267] At 20 °C, 0.66 g (2.75 mmol) of 2-amino-7-Boc-7-azaspirocyclo[3.5]nonane and 0.6 g (2.02 mmol) of 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (3 mL) were dissolved in dimethyl sulfoxide. Potassium fluoride (468.42 mg, 8.06 mmol) was then added to the reaction mixture. After the addition was complete, the reaction mixture was heated to 140 °C and stirred at this temperature for 12 hours. TLC showed complete consumption of the starting materials. The reaction mixture was cooled to room temperature and then poured into water for extraction with ethyl acetate. The combined organic phases were concentrated to dryness to obtain the crude product. The crude product was purified by column chromatography to obtain 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (0.68 g, yield: 65.24%), a yellow solid.

[0268] (2) N-(7-azaspiro[3.5]nonane-2-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-amine

[0269] At 25°C, 0.68 g (1.36 mmol) of 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester was dissolved in dichloromethane (3 mL). Dioxane hydrochloride (4 M, 5 mL) was added to the solution, and the mixture was stirred at 25°C for 0.5 hours after the addition was complete. LCMS showed that the starting material was completely consumed. The pH of the reaction solution was adjusted to ~8 with ammonia, and then concentrated to dryness to obtain the crude product. The crude product was purified by Prep-HPLC to obtain N-(7-azaspiro[3.5]nonane-2-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (0.5 g, yield: 91.87%), a white solid. MS(ESI): m / z 402.1 [M+H] + . 1H NMR (400MHz, DMSO-d6) δ8.94(s,1H),8.28(d,J=6.7Hz,1H),8.07(s,1H),7.79(d,J=9.7Hz,1H),7.71-7.63(m,2H),7.44(d,J=6.1Hz,1H),6.72(d,J =9.7Hz,1H),4.25-4.13(m,1H),2.69-2.62(m,2H),2.60-2.55(m,2H),2. 38-2.30(m,2H),1.72-1.61(m,2H),1.56-1.49(m,2H),1.48-1.41(m,2H).

[0270] Example 8: N-(6-azaspiro[3.4]octane-2-ylmethyl)-3-(3-(trifluoromethyl)phenyl)imidazol[1,2-b]pyridazine-6-amine (Compound 18)

[0271]

[0272] (1) 2-[[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]methyl]-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester

[0273] Referring to the method in step (1) of Example 7, 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (50 mg, 167.98 μmol) and 2-(aminomethyl)-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester (52.48 mg, 218.37 μmol) were used as raw materials to obtain 2-[[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]methyl]-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester (45 mg, crude product), a yellow oily substance.

[0274] (2) N-(6-azaspiro[3.4]octane-2-ylmethyl)-3-(3-(trifluoromethyl)phenyl)imidazol[1,2-b]pyridazine-6-amine

[0275] Following the method in step (2) of Example 7, using 2-[[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]methyl]-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester (45 mg, 89.72 μmol) as a starting material, N-(6-azaspiro[3,4]octane-2-ylmethyl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-amine (9.4 mg, yield: 26.10%) was obtained as a yellow solid. MS (ESI): m / z 402.0 [M+H]+ . 1 H NMR (400MHz, DMSO-d6) δ8.97(s,1H),8.32(d,J=7.39Hz,1H),8.09(s,1H),7.79(d,J=9.66Hz,1H),7.62-7.72(m,2H),7.25(t,J=5. 13Hz, 1H), 6.76 (d, J = 9.66Hz, 1H), 3.14-3.24 (m, 4H), 2.85-3.00 (m, 3H), 2.56-2.53 (m, 1H), 2.00-2.18 (m, 2H), 1.70-1.90 (m, 4H).

[0276] Example 9: N-(azacycloheptane-4-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (Compound 19)

[0277]

[0278] (1) 4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]azacycloheptane-1-carboxylic acid tert-butyl ester

[0279] Following the method in step (1) of Example 7, 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (50 mg, 167.98 μmol) and tert-butyl aziridine-1-carboxylate (720.0 mg, 3.36 mmol) were used as raw materials to obtain 4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]tert-butyl aziridine-1-carboxylate (0.4 g, yield: 50.08%), a yellow solid.

[0280] (2) N-(azacycloheptane-4-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine

[0281] Following the method in step (2) of Example 7, 4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]azacycloheptane-1-carboxylic acid tert-butyl ester (0.4 g, 105.15 μmol) was used as the starting material to obtain N-(azacycloheptane-4-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (0.22 g, yield: 69.67%), a yellow solid. MS (ESI): m / z 376.1 [M+H] + . 1H NMR (400MHz, DMSO-d6) δ8.73 (s, 1H), 8.40 (d, J = 7.2Hz, 1H), 8.08-8.04 (m, 1H), 7.82-7.75 (m, 1H), 7.72-7.63 (m, 2H), 7.14-7.03(m,1H),6.76(d,J=9.7Hz,1H),3.93(td,J=3.8,7.8Hz,1H),2.91-2.76(m,3H),2.73-2.64(m,1H),2.53(br s,1H),2.11-1.94(m,2H),1.79-1.67(m,2H),1.63(dt,J=4.6,9.1Hz,1H),1.60-1.49(m,1H).

[0282] Example 10: 2-((1r,4r)-4-((3-(5-(trifluoromethyl)thiophene-2-yl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)prop-2-ol (Compound 20)

[0283]

[0284] (1) 6-Chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine

[0285] At 20 °C, 2-bromo-5-(trifluoromethyl)thiophene (1.81 g, 7.81 mmol), potassium carbonate (1.80 g, 13.02 mmol), and triphenylphosphine (341.59 mg, 1.30 mmol) were added sequentially to a toluene (10 mL) solution of 6-chloroimidazolo[1,2-b]pyridazine (1 g, 6.51 mmol). The system was then purged three times with nitrogen. After purging, palladium acetate (146.19 mg, 651.17 μmol) was added to the reaction system under nitrogen protection. After the addition was complete, the reaction solution was heated to 120 °C and stirred at 120 °C for 12 hours. TLC showed that the reaction was complete, and LCMS showed that a product was formed. The reaction solution was cooled to room temperature, poured into water, and then extracted with ethyl acetate. The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated to dryness to give 1.8 g of crude 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine, a yellow solid.

[0286] (2)2-((1r,4r)-4-((3-(5-(trifluoromethyl)thiophen-2-yl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)prop-2-ol

[0287] At 20 °C, 2-((1r,4r)-4-aminocyclohexyl)prop-2-ol (310.68 mg, 1.98 mmol), cesium fluoride (500.18 mg, 3.29 mmol), and N,N-diisopropylethylamine (425.56 mg, 3.29 mmol) were added sequentially to a solution of 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine (0.5 g, 1.65 mmol) in dimethyl sulfoxide (5 mL). After the addition was complete, the system was heated to 100 °C and stirred at 100 °C for 12 hours. TLC showed that the reaction was complete, and LCMS showed that a product was formed. The reaction solution was cooled to room temperature and poured into water, then extracted with ethyl acetate. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated to dryness to obtain the crude product. The crude product was purified by Prep-HPLC to give 2-((1r,4r)-4-((3-(5-(trifluoromethyl)thiophene-2-yl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)prop-2-ol (0.18 g, yield: 25.76%), a white solid. MS (ESI): m / z 425.1 [M+H] + . 1 HNMR(400MHz, DMSO-d6)δ8.14(s,1H),7.92-7.70(m,3H),7.28(d,J=6.8Hz,1H),6.73(d,J=9.7Hz,1H),4.09( s,1H),3.67(brs,1H),2.27(brs,2H),1.94(brs,2H),1.30(d,J=9.0Hz,1H),1.25-1.14(m,4H),1.07(s,6H).

[0288] Example 11: (1S,3R)-3-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cycloheptanol (Compound 21)

[0289]

[0290] At 25°C, 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (50 mg, 211.26 μmol) and (1S,3R)-3-aminocycloheptanol (36 mg, 217.31 μmol) were dissolved in dimethyl sulfoxide (1 mL) in an 8 mL reaction flask, followed by the addition of N,N-diisopropylethylamine (68.26 mg, 528.14 μmol) and cesium fluoride (80.22 mg, 528.14 μmol). After the addition was complete, the reaction temperature was raised to 140°C and the reaction was carried out at this temperature for 12 hours. LC-MS showed that the reactants were completely consumed. The reaction solution was cooled to room temperature, poured into water, and extracted with ethyl acetate. The combined organic phases were concentrated to dryness to obtain the crude product. The crude product was purified by Prep-HPLC to give a white solid (1S,3R)-3-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cycloheptanol (7 mg, yield: 8.49%). MS (ESI): m / z 391.2 [M+H) + . 1 H NMR (400MHz, DMSO-d6) δ8.71(s,1H),8.42(d,J=7.4Hz,1H),8.06(s,1H),7.78(d,J=9.8Hz,1H),7.72-7.64(m,2H),7.10(d,J=7.5Hz ,1H),6.72(d,J=9.8Hz,1H),4.49(d,J=4.1Hz,1H),3.88-3.67(m,2H),2.16(d,J=12.3Hz,1H),2.01-1.81(m,2H),1.69-1.40(m,7H).

[0291] Example 12: cis-4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cycloheptanol (compound 23)

[0292]

[0293] Following the method of Example 11, using cis-4-aminocycloheptanol hydrochloride (36 mg, 217.32 μmol) and 5-(6-chloroimidazolo[1,2-b]pyridazin-3-yl)thiazole (50 mg, 211.26 μmol) as starting materials, cis-4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cycloheptanol (16.6 mg, yield: 20.13%) was obtained as a white solid. MS (ESI): m / z 391.2 [M+H] + . 1H NMR (400MHz, CDCl3) δ8.68(s,1H),8.18-8.10(m,1H),7.89(s,1H),7.70(d,J=9.7Hz,1H),7.62-7.55(m,2H),6.46(d,J=9.7Hz,1H),4.50(d,J=7 .5Hz,1H),4.18-4.02(m,2H),2.21-2.11(m,1H),2.09-2.00(m,1H),1.9 9-1.92(m,2H),1.90-1.76(m,3H),1.68-1.63(m,1H),1.53-1.39(m,2H).

[0294] Example 13: N-(6-azaspiro[3.4]octane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-amine (Compound 24)

[0295]

[0296] (1) 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester

[0297] Referring to the method in step (1) of Example 7, 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (0.1 g, 335.95 μmol) and 2-amino-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester (98.84 mg, 436.74 μmol) were used as raw materials to obtain 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester (0.12 g, crude product), a yellow oily substance.

[0298] (2) N-(6-azaspiro[3.4]octane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-amine

[0299] Following the method in step (2) of Example 7, 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-6-azaspiro[3,4]octane-6-carboxylic acid tert-butyl ester (60 mg, 123.07 μmol) was used as a starting material to obtain N-(6-azaspiro[3,4]octane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-amine (5.1 mg, yield: 10.70%), a yellow solid. MS (ESI): m / z 388.2 [M+H] + . 1H NMR(400MHz,DMSO-d6)δ8.88(s,1H),8.32-8.39(m,1H),8.08-8.12(m,1H), 7.79-7.86(m,1H),7.65-7.74(m,2H),7.53(d,J=5.99Hz,1H),6.73(d,J=9.7 8Hz,1H),4.13-4.24(m,1H),3.49-3.59(m,1H),3.12(s,2H),3.06(t,J=7.1 5Hz, 2H), 2.56 (d, J = 3.18Hz, 2H), 2.00-2.08 (m, 2H), 1.92 (t, J = 7.34Hz, 2H).

[0300] Example 14: [(2R,5S)-5-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]tetrahydropyran-2-yl]methanol (Compound 25)

[0301]

[0302] (1)(2S)-2-(tert-butoxycarbonylamino)hex-5-enoic acid methyl ester

[0303] Activated zinc powder (44.70 g, 683.6 mmol) and N,N-dimethylformamide (200 mL) were added to reaction flask 1. The reaction system was then cooled to 0 °C, and a solution of (2R)-2-(tert-butoxycarbonylamino)-3-iodopropionate (45 g, 136.72 mmol) in N,N-dimethylformamide (50 mL) was added dropwise. The reaction system was heated to 20 °C and stirred for one hour. The supernatant was then collected and set aside. In reaction flask 2, 3-bromopropene (28.12 g, 232.4 mmol) was added to N,N-dimethylformamide (200 mL) containing cuprous bromide (35.30 g, 246.1 mmol) at 20 °C. The mixture was then cooled to -15 °C, and the supernatant from reaction flask 1 was added dropwise. The mixture was then heated to 20 °C and stirred for 12 hours. TLC (petroleum ether / ethyl acetate = 3 / 1) showed that the starting material reacted completely and new spots formed, indicating the formation of the product. 500 mL of ethyl acetate was added to the reaction system and stirring was continued for 15 minutes, followed by the addition of 500 mL of water. The organic phase was washed successively with 1M sodium thiosulfate solution (300 mL) and water (300 mL), then dried over anhydrous sodium sulfate, filtered, and concentrated completely to obtain the crude product. The crude product was purified by column chromatography (petroleum ether / ethyl acetate = 100 / 1 to 100% ethyl acetate) to give methyl (2S)-2-(tert-butoxycarbonylamino)hex-5-enoate (20 g, yield: 60.12%), a colorless oil.

[0304] (2) N-[(1S)-1-(hydroxymethyl)pent-4-enyl] tert-butyl carbamate

[0305] Under nitrogen protection at 20°C, lithium borohydride (1.79 g, 82.20 mmol) was added in portions to tetrahydrofuran (100 mL), followed by the slow dropwise addition of a tetrahydrofuran (60 mL) solution of (2S)-2-(tert-butoxycarbonylamino)hex-5-enoic acid methyl ester (20 g, 82.20 mmol). The reaction was then stirred at 20°C for 12 hours. TLC (petroleum ether / ethyl acetate = 5 / 1) showed that the starting material reacted completely and new spots formed, indicating the formation of the product. The reaction solution was quenched in 500 mL of water and extracted with ethyl acetate (300 mL × 2). The organic phase was washed with 500 mL of saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to remove the solvent, yielding N-[(1S)-1-(hydroxymethyl)pent-4-enyl]carbamate tert-butyl ester (12 g, yield: 67.81%), a colorless oil. The crude product was used directly in the next step. 1 H NMR (400MHz, CDCl3) δ5.74 (tdd, J=6.6, 10.3, 17.0Hz, 1H), 5.01-4.88 (m, 2H), 4.59 (brs, 1H ),3.68-3.55(m,2H),3.55-3.41(m,1H),2.11-2.01(m,2H),1.61-1.41(m,3H),1.38(s,9H).

[0306] (3) N-[(1S)-1-(hydroxymethyl)-3-(ethylene-2-yl)propyl] tert-butyl carbamate

[0307] At 20°C, a dichloromethane solution (150 mL) of N-[(1S)-1-(hydroxymethyl)pent-4-enyl]carbamate tert-butyl (10 g, 46.45 mmol) and an aqueous solution of potassium dihydrogen phosphate (18.96 g, 139.35 mmol) (200 mL) were mixed together, followed by the addition of m-chloroperoxybenzoic acid (8.02 g, 46.45 mmol) at 20°C, and the mixture was stirred for 12 hours. TLC (petroleum ether / ethyl acetate = 1 / 1) showed that the starting material reacted completely and new spots formed, indicating the formation of the product. The reaction mixture was separated to obtain the organic phase, and the aqueous phase was extracted with dichloromethane (100 mL × 2). The organic phases were combined and concentrated under reduced pressure to remove the solvent, yielding the crude product. The crude product was purified by column chromatography (petroleum ether / ethyl acetate = 100 / 1 to 100% ethyl acetate) to give N-[(1S)-1-(hydroxymethyl)-3-(ethylene oxide-2-yl)propyl] tert-butyl carbamate (4 g, yield: 37.23%), a yellow oil.

[0308] (4) N-[(3S,6R)-6-(hydroxymethyl)tetrahydropyran-3-yl]tert-butyl carbamate

[0309] At 20°C, camphor-10-sulfonic acid (97.40 mg, 389.1 μmol) was added to a solution of N-[(1S)-1-(hydroxymethyl)-3-(ethyleneoxy-2-yl)propyl] tert-butyl carbamate (0.9 g, 3.89 mmol) in dichloromethane (9 mL), and the mixture was stirred at 20°C for 12 hours. TLC (petroleum ether / ethyl acetate = 0 / 1) showed that the starting material reacted completely and new spots formed, indicating the formation of the product. The reaction solution was concentrated to remove the solvent, yielding a crude product, which was then purified by column chromatography (petroleum ether / ethyl acetate = 100 / 1 to 100% ethyl acetate) to give N-[(3S,6R)-6-(hydroxymethyl)tetrahydropyran-3-yl] tert-butyl carbamate (0.28 g, yield: 31.11%), a white solid. 1 H NMR(400MHz, CDCl3)δ4.22(brs,1H),4.06-4.02(m,1H),3.58-3.50(m,2H),3.47-3.42(m,1H),3.48-3.42(m,1H),3.33-3.2 5(m,1H),2.95(t,J=10.6Hz,1H),2.04(d,J=12.3Hz,1H),1.88(d,J=12.7Hz,1H),1.38(d,J=5.4Hz,10H),1.29-1.21(m,1H).

[0310] (5) [(2R,5S)-5-aminotetrahydropyran-2-yl]methanol hydrochloride

[0311] At 20°C, 0.3 g (1.30 mmol) of N-[(3S,6R)-6-(hydroxymethyl)tetrahydropyran-3-yl]carbamate tert-butyl ester was added to dioxane hydrochloride (3 mL), followed by stirring at 20°C for 2 hours. TLC (petroleum ether / ethyl acetate = 0 / 1) showed that the starting material reacted completely and new spots formed, indicating the formation of the product. The reaction solution was concentrated under reduced pressure to remove the solvent, yielding [(2R,5S)-5-aminotetrahydropyran-2-yl]methanol hydrochloride (0.2 g, yield: 91.98%), a white solid. The crude product was used directly in the next step.

[0312] (6)[(2R,5S)-5-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]tetrahydropyran-2-yl]methanol

[0313] Following the method in step (1) of Example 7, using [(2R,5S)-5-aminotetrahydropyran-2-yl]methanol hydrochloride (0.10 g, 760 μmol) and 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (250 mg, 840.0 μmol) as raw materials, [(2R,5S)-5-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]tetrahydropyran-2-yl]methanol (0.0054 g, yield: 2.84%) was obtained as a white solid. MS (ESI): m / z 393.1 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.89 (s, 1H), 8.37 (d, J = 7.5Hz, 1H), 8.14 (s, 1H), 7.87 (d, J=9.9Hz,1H),7.81-7.67(m,2H),7.34(d,J=6.6Hz,1H),7.03(d,J=9.8Hz,1H),4.6 8(t,J=5.4Hz,1H),4.12(d,J=11.1Hz,1H),3.90(brs,1H),3.69(d,J=10.6Hz,1H) ,3.57-3.49(m,3H),2.18(d,J=13.7Hz,1H),1.94-1.77(m,1H),1.73-1.52(m,2H).

[0314] Example 15: N-(7-methyl-7-azaspiro[3.5]nonane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-amine (Compound 26)

[0315]

[0316] (1) 2-((3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)-7-azaspiro[3,5]nonane-7-carboxylic acid tert-butyl ester

[0317] Following the method in step (1) of Example 7, 2-amino-7-Boc-7-azaspiro[3.5]nonane (0.11 g, 457.68 μmol) and 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (0.1 g, 335.95 μmol) were used as raw materials to obtain 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (75 mg, yield: 44.51%), a yellow solid.

[0318] (2) N-(7-methyl-7-azaspiro[3.5]nonane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-amine

[0319] At 25°C, 40 mg (79.75 μmol) of 2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester was dissolved in 1 mL of THF. Lithium aluminum hydride (7.5 mg, 197.61 μmol) was added at 25°C, and the reaction mixture was heated to 30°C and stirred at 30°C for 16 hours. LC-MS showed complete consumption of the starting material. The reaction was quenched by adding sodium sulfate decahydrate at 25°C. After stirring at 25°C for 4 hours, the mixture was filtered, the filter cake was washed with ethyl acetate, and the filtrate was concentrated to obtain the crude product. The crude product was purified by Prep-HPLC to obtain N-(7-methyl-7-azaspiro[3.5]nonane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-amine (9 mg, yield: 27.16%), a pale yellow gelatinous substance. MS (ESI): m / z 416.2 [M+H] + . 1 H NMR(400MHz,CD3OD)δ8.91(s,1H),8.24-8.15(m,1H),7.93(s,1H),7.71-7.61(m,3H),6.75(d,J=9.6Hz,1H),4 .32(t,J=7.9Hz,1H),3.55-3.45(m,1H),3.23-3.10(m,1H),2.56-2.37(m,4H),2.28(s,3H),1.84-1.66(m,6H).

[0320] Example 16: N-(1-methylazacycloheptane-4-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (Compound 27)

[0321]

[0322] It is obtained by further methylation of compound 19.

[0323] Acetic acid (399.92 μg, 6.66 μmol) was added dropwise to a mixture of dichloromethane (0.3 mL) and methanol (0.3 mL) containing N-(azacycloheptan-4-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (0.025 g, 66.60 μmol) and paraformaldehyde (12 mg, 99.90 μmol). The mixture was stirred at 25 °C for 30 minutes. Then, sodium cyanoborohydride (16.74 mg, 266.39 μmol) was added to the reaction mixture, and the mixture was stirred at 25 °C for 12 hours. LC-MS analysis showed complete consumption of the starting materials and product formation. The reaction solution was concentrated under reduced pressure to remove the solvent, yielding a crude product. The crude product was dissolved in methanol and filtered. The filtrate was directly purified by Prep-HPLC to obtain N-(1-methylazacycloheptane-4-yl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (11.9 mg, yield: 45.89%), a yellow oil. MS (ESI): m / z 390.1 [M+H] + . 1 H NMR (400MHz, CDCl3) δ8.55(s,1H),8.07(t,J=3.8Hz,1H),7.78(s,1H),7.59(d,J=9.5Hz,1H),7.48(d,J=4.9Hz,2H),6.41(d,J=9.6Hz,1H),4.87(d,J= 8.0Hz,1H),4.17(tq,J=4.1,7.9Hz,1H),2.76-2.58(m,2H),2.51-2.41(m, 2H),2.33(s,3H),2.10-1.99(m,1H),1.92-1.82(m,3H),1.78-1.57(m,2H).

[0324] Example 17: N-(azacycloheptane-4-yl)-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-amine (Compound 28)

[0325]

[0326] (1) 4-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]azacycloheptane-1-carboxylic acid tert-butyl ester

[0327] Following the method in step (2) of Example 10, using 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine (0.22 g, 724.42 μmol) and 4-aminoazacycloheptane-1-carboxylic acid tert-butyl ester (186.30 mg, 869.31 μmol) as raw materials, 4-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine-6-yl]amino]azacycloheptane-1-carboxylic acid tert-butyl ester (0.26 g, yield: 74.53%) was obtained as a yellow solid.

[0328] (2) N-(azacycloheptane-4-yl)-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-amine

[0329] Following the method in step (2) of Example 7, using 4-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]azacycloheptane-1-carboxylic acid tert-butyl ester (0.25 g, 519.17 μmol) as the starting material, N-(azacycloheptane-4-yl)-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-amine (0.12 g, yield: 60.60%) was obtained as a yellow solid. MS (ESI): m / z 382.0 [M+H] + . 1 H NMR (400MHz, CD3OD) δ7.98 (s, 1H), 7.70-7.65 (m, 2H), 7.58 (dd, J = 1.1, 4.0Hz, 1H), 6.77 (d, J = 9.8Hz, 1H),4.17-4.06(m,1H),3.21-3.11(m,1H),3.09-2.92(m,3H),2.43-2.26(m,2H),2.00-1.70(m,4H).

[0330] Example 18: 4-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]bicyclo[2.2.2]octane-1-ol (compound 29)

[0331]

[0332] Following the method in step (2) of Example 10, using 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine (0.03 g, 98.78 μmol) and 4-aminobicyclo[2.2.2]octane-1-ol hydrochloride (21.06 mg, 118.54 μmol) as starting materials, 4-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine-6-yl]amino]bicyclo[2.2.2]octane-1-ol (10 mg, yield: 24.79%) was obtained as a yellow solid. MS (ESI): m / z 409.0 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.13(s,1H),7.81-7.69(m,3H),6.89(s,1H),6.76(d,J=9.8Hz,1H),4.38(s,1H),2.25-2.17(m,6H),1.76-1.66(m,6H).

[0333] Example 19: N-(7-cyclopropyl-7-azaspiro[3.5]nonane-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-amine (Compound 30)

[0334]

[0335] At 25°C, N-(7-azaspiro[3.5]non-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazolium[1,2-b]pyridazine-6-amine (60 mg, 149.47 μmol), sodium cyanoborohydride (56.36 mg, 896.80 μmol), and acetic acid (53.85 mg, 896.80 μmol, 51.29 μL) were added to a methanol (4 mL) solution of 1-ethoxy-1-trimethoxycyclopropane (156.32 mg, 896.80 μmol, 180.30 μL). After the addition was complete, the reaction solution was heated to 60°C and stirred at 60°C for 12 hours. LCMS showed complete consumption of the starting material. The reaction solution was directly purified by Prep-HPLC without any pretreatment to obtain N-(7-azaspiro[3.5]non-2-yl)-3-(3-(trifluoromethyl)phenyl)imidazol[1,2-b]pyridazin-6-amine (27 mg, yield: 46.28%), a white solid. MS (ESI): m / z 442.3 [M+H] + . 1H NMR (400MHz, CDCl3) δ8.70(s,1H),8.00(d,J=6.8Hz,1H),7.81(s,1H),7.62(d,J=9.6Hz,1H),7.55-7.44(m,2H),6. 39(d,J=9.6Hz,1H),4.46(d,J=6.0Hz,1H),4.32-4.20(m,1H),2.65-2.34(m,6H),1.72-1.54(m,7H),0.38(brs,4H).

[0336] Example 20: N-(7-azaspiro[3.5]nonane-2-yl)-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-amine (Compound 31)

[0337]

[0338] (1) 2-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3,5]nonane-7-carboxylic acid tert-butyl ester

[0339] Following the method in step (2) of Example 10, using 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine (220 mg, 724.42 μmol) and 2-amino-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (208.93 mg, 869.31 μmol) as raw materials, 2-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (0.2 g, yield: 54.39%) was obtained as a yellow solid.

[0340] (2) N-(7-azaspiro[3.5]nonane-2-yl)-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine-6-amine

[0341] Following the method in step (2) of Example 7, using 2-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (0.2 g, 394.03 μmol) as a starting material, N-(7-azaspiro[3.5]nonane-2-yl)-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-amine (0.134 g, yield: 83.46%) was obtained as a white solid. MS (ESI): m / z 408.1 [M+H] + . 1H NMR (400MHz, DMSO-d6) δ8.16 (s, 1H), 7.88-7.72 (m, 4H), 6.76 (d, J = 9.7Hz, 1H), 4.38 -4.27(m,1H),3.04(brs,2H),2.97-2.90(m,2H),2.55(brs,2H),1.87-1.69(m,6H).

[0342] Example 21: 6-(((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)amino)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid (Compound 42)

[0343]

[0344] (1) Ethyl 3-bromo-6-chloroimidozono[1,2-b]pyridazine-2-carboxylic acid ester

[0345] Ethyl 6-chloroimidazolo[1,2-b]pyridazine-2-carboxylate (2 g, 8.8 mmol) and NBS (1.9 g, 10.6 mmol) were dissolved in dichloromethane (20 mL). The reaction mixture was stirred at 40 °C for 48 hours. A small amount of water was added, and the mixture was extracted separately with ethyl acetate (40 mL x 2). The extract was dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and purified by reverse-phase column chromatography to obtain ethyl 3-bromo-6-chloroimidazolo[1,2-b]pyridazine-2-carboxylate (2.3 g, yield: 88%), a white solid. MS (ESI): m / z 304.3 [M+H] + .

[0346] (2) Following the method in step (2) of Example 1, using 3-bromo-6-chloroimidozolo[1,2-b]pyridazine-2-carboxylic acid ethyl ester (300 mg, 0.9 mmol) and (3-(trifluoromethyl)phenyl)boronic acid (131 mg, 0.6 mmol) as raw materials, 6-chloro-3-(3-(trifluoromethyl)phenyl)imidozolo[1,2-b]pyridazine-2-carboxylic acid ethyl ester (60 mg, yield: 16%) was obtained as a yellow solid.

[0347] (3) Following the method in step (3) of Example 1, using ethyl 6-chloro-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-2-carboxylate (60 mg, 0.4 mmol) and 2-((1r,4r)-4-aminocyclohexyl)propanol (50 mg, 0.4 mmol) as raw materials, 6-(((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)amino)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-2-carboxylic acid (15.8 mg, yield: 10%) was obtained as a white solid. MS (ESI): m / z 463.3 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.14(s,1H),8.01(d,J=6.8Hz,1H),7.76(d,J=7.6Hz,2H), 7.67(t,J=8.0Hz,1H),7.09(d,J =7.2Hz, 1H), 6.78 (d, J = 9.2Hz, 1H), 4.01 (s, 1H), 2.03 (d, J = 9.8Hz, 2H), 1.78 (d, J = 11.6Hz, 2H), 1.23-0.90 (m, 11H).

[0348] Example 22: (1R,3R)-3-((3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cycloheptanol (compound 44)

[0349]

[0350] Following the method in step (2) of Example 10, using (1R,3R)-3-aminocycloheptanol hydrochloride (35 mg, 211.28 μmol) and 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (62.89 mg, 211.28 μmol) as raw materials, (1R,3R)-3-((3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-6-yl)amino)cycloheptanol (8.1 mg, yield: 9.82%) was obtained as a yellow solid. MS (ESI): m / z 391.1 [M+H] + . 1H NMR (400MHz, DMSO-d6) δ8.74 (s, 1H), 8.43 (d, J = 7.46Hz, 1H), 8.06 (s, 1H), 7.77 (d,J=9.66Hz,1H),7.63-7.73(m,2H),7.07(d,J=7.34Hz,1H),6.76(d,J=9.66H z,1H),4.41(d,J=3.79Hz,1H),4.01-4.09(m,1H),3.86(dd,J=8.68,3.67Hz,1H ),2.02-2.12(m,2H),1.82-1.96(m,2H),1.65-1.79(m,2H),1.30-1.56(m,4H).

[0351] Example 23: (1R,4R)-4-((3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cycloheptanol (compound 45)

[0352]

[0353] Following the method in step (1) of Example 7, using (1R,4R)-4-aminocycloheptanol hydrochloride (28.90 mg, 174.45 μmol) and 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (41.29 mg, 174.45 μmol) as starting materials, 4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]cycloheptanol (11 mg, yield: 16.15%) was obtained as a white solid. MS (ESI): m / z 391.2 [M+H] + . 1 H NMR (400MHz, CD3OD) δ8.60(s,1H),8.38-8.29(m,2H),7.93(d,J=9.9Hz,1H),7.87-7.74(m,2H),7.19(d,J= 9.8Hz,1H),4.03-3.97(m,1H),3.92-3.78(m,1H),2.21-2.06(m,2H),2.05-1.93(m,2H),1.73-1.49(m,6H).

[0354] Example 24: [(2S,5R)-5-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]tetrahydropyran-2-yl]methanol (Compound 46)

[0355]

[0356] Following the method in step (1) of Example 7, using [(2S,5R)-5-aminotetrahydropyran-2-yl]methanol hydrochloride (Example 28, 30.00 mg, 228.71 μmol) and 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine (76.40 mg, 251.58 μmol) as raw materials, [(2S,5R)-5-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine-6-yl]amino]tetrahydropyran-2-yl]methanol (0.005 g, yield: 5.49%) was obtained as a white solid. MS (ESI): m / z 399.0 [M+H] + . 1 HNMR (400MHz, DMSO-d6) δ8.16 (s, 1H), 7.84 (d, J = 9.7Hz, 1H), 7.81-7.75 (m ,2H),7.26(d,J=6.9Hz,1H),6.74(d,J=9.8Hz,1H),4.72-4.61(m,1H),4.17 (d,J=8.5Hz,1H),3.92(s,1H),3.46-3.39(m,1H),3.30-3.23(m,2H),3.17 (t,J=10.6Hz,1H),1.82(d,J=11.3Hz,1H),1.53-1.31(m,2H),1.15(s,1H).

[0357] Example 25: [(2R,5S)-5-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazin-6-yl]amino]tetrahydropyran-2-yl]methanol (Compound 47)

[0358]

[0359] Following the method in step (1) of Example 7, using [(2R,5S)-5-aminotetrahydropyran-2-yl]methanol hydrochloride (Example 14, 30.00 mg, 228.71 μmol) and 6-chloro-3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine (76.40 mg, 251.58 μmol) as raw materials, a yellow solid [(2R,5S)-5-[[3-[5-(trifluoromethyl)-2-thienyl]imidazo[1,2-b]pyridazine-6-yl]amino]tetrahydropyran-2-yl]methanol (0.006 g, yield: 6.58%) was obtained. MS (ESI): m / z 399.0 [M+H] + . 1HNMR(400MHz,CD3OD)δ8.00(s,1H),7.71(d,J=9.8Hz,2H),7.58(d,J=3.9Hz,1H),6.76(d,J=9.8Hz,1H),4.35(dd,J=2.3,10.7Hz,1H), 4.08(d,J=11.2Hz,1H),3.62-3.54(m,2H),3.50(brs,1H),3.29-3.23(m,1H),2.44(brs,1H),1.86(d,J=9.8Hz,1H),1.62-1.49(m,2H).

[0360] Example 26: N-(7-azaspiro[3.5]nonane-2-ylmethyl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (Compound 15)

[0361]

[0362] (1) 2-[[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]methyl]-7-azaspiro[3,5]nonane-7-carboxylic acid tert-butyl ester

[0363] Referring to the method in step (1) of Example 7, 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (0.1 g, 335.95 μmol) and 2-(aminomethyl)-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (111.09 mg, 436.74 μmol) were used as raw materials to obtain 2-[[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]methyl]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (90 mg, crude product), a yellow oily substance.

[0364] (2) N-(7-azaspiro[3.5]nonane-2-ylmethyl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-amine

[0365] A solution of 2-[[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]methyl]-7-azaspiro[3.5]nonane-7-carboxylic acid tert-butyl ester (90 mg, 174.56 μmol) in hydrochloric acid / methanol (4 M, 900.00 μL) was stirred at 20 °C for 2 hours. LC-MS showed that the product had been consumed as expected and was detected. The reaction solution was concentrated to obtain a crude product. The crude product was dissolved in methanol, then water was added, and the pH was adjusted to >7 with ammonia. The resulting solution was directly purified by Prep-HPLC to give a white solid product N-(7-azaspiro[3.5]alkyl-2-ylmethyl)-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-amine (12 mg, yield: 16.55%). MS (ESI): m / z 416.1 [M+H] + . 1 H NMR (400MHz, CD3OD) δ8.86 (s, 1H), 8.19 (d, J = 7.2Hz, 1H), 7.88 (s, 1H), 7.63-7.57 (m, 3H), 6.72 (d, J = 9.5Hz, 1H), 3. 40(d,J=7.5Hz,2H),2.81-2.76(m,2H),2.72-2.62(m,3H),2.04-1.98(m,2H),1.66-1.61(m,2H),1.59-1.52(m,4H).

[0366] Example 27: 2-[(1r,4r)-4-[(3-thiazolyl-2-ylimidazol[1,2-b]pyridazin-6-yl)amino]cyclohexyl]prop-2-ol (Compound 17)

[0367]

[0368] (1) 2-(6-clomizo[1,2-b]pyridazin-3-yl)thiazole

[0369] Under nitrogen protection at 25°C, palladium dichloride bis(triphenylphosphine) chloride (17.58 mg, 25.05 μmol) was added to a solution of 6-chloro-3-iodo-imidazo[1,2-b]pyridazine (0.35 g, 1.25 mmol) and tributyl(thiazol-2-yl)stanane (468.61 mg, 1.25 mmol) in N,N-dimethylformamide (3.5 mL). After the addition was complete, the reaction mixture was stirred at 110°C for 6 hours. LC-MS showed that the starting material had been consumed and product had been formed. The reaction mixture was poured into 10 mL of aqueous solution, extracted with ethyl acetate, and the organic phases were combined and washed with saturated brine. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain 2-(6-chloroimidazo[1,2-b]pyridazine-3-yl)thiazole (0.22 g, crude product), a white solid.

[0370] (2) 2-[4-[(3-thiazolyl-2-ylimidazol[1,2-b]pyridazin-6-yl)amino]cyclohexyl]prop-2-ol

[0371] Following the method in step (1) of Example 7, using 2-((1r,4r)-4-aminocyclohexyl)prop-2-ol (132.88 mg, 845.02 μmol) and 2-(6-chloroimidazole[1,2-b]pyridazin-3-yl)thiazole (200 mg, 845.02 μmol) as raw materials, 2-[(1r,4r)-4-[(3-thiazol-2-ylimidazol[1,2-b]pyridazin-6-yl)amino]cyclohexyl]prop-2-ol (7.5 mg, yield: 2.48%), a pale yellow solid, was obtained. MS (ESI): m / z 358.2 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.06(s,1H),7.96(brs,1H),7.87-7.80(m,2H),7.24(d,J=6.4Hz,1H),6.78(d,J=9 .3Hz,1H),4.10(s,1H),3.70(brs,1H),2.31(brs,2H),1.90(brs,2H),1.23(d,J=8.4Hz,5H),1.10(s,6H).

[0372] Example 28: [(2S,5R)-5-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]tetrahydropyran-2-yl]methanol (Compound 22)

[0373]

[0374] (1) [(2S,5R)-5-aminotetrahydropyran-2-yl]methanol hydrochloride

[0375] A solution of N-[(3R,6S)-6-(hydroxymethyl)tetrahydropyran-3-yl]carbamate tert-butyl (150 mg, 648.54 μmol) in hydrochloric acid / methanol (4 M, 1.50 mL) was stirred at 20 °C for 1 hour. TLC showed that the starting material was completely consumed. The reaction solution was concentrated under reduced pressure to obtain [(2S,5R)-5-aminotetrahydropyran-2-yl]methanol hydrochloride (85 mg, crude product), a white solid.

[0376] (2) 2-[4-[(3-thiazolyl-2-ylimidazol[1,2-b]pyridazin-6-yl)amino]cyclohexyl]prop-2-ol

[0377] Following the method in step (1) of Example 7, using [(2S,5R)-5-aminotetrahydropyran-2-yl]methanol hydrochloride (85 mg, 507.06 μmol) and 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (166.03 mg, 557.76 μmol) as raw materials, a white solid product [(2S,5R)-5-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]tetrahydropyran-2-yl]methanol (9.4 mg, yield: 4.72%) was obtained. MS (ESI): m / z 393.2 [M+H] + . 1 HNMR(400MHz,DMSO-d6)δ8.79(s,1H),8.32(d,J=7.2Hz,1H),8.06(s,1H),7.80(d,J=9.7Hz, 1H),7.72-7.64(m,2H),7.05(d,J=7.5Hz,1H),6.72(d,J=9.7Hz,1H),4.65(t,J=5.7Hz,1H),4 .11-4.05(m,1H),3.88-3.77(m,1H),3.45-3.38(m,1H),3.32-3.27(m,2H),3.11(t,J=10.5H z, 1H), 2.24 (d, J = 11.8Hz, 1H), 1.78 (d, J = 12.2Hz, 1H), 1.51-1.38 (m, 1H), 1.36-1.23 (m, 1H).

[0378] Example 29: 2-((1r,4r)-4-((3-(3-(furan-2-yl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)prop-2-ol (compound 48)

[0379]

[0380] (1)2-(3-bromophenyl)furan

[0381] 1-Bromo-3-iodobenzene (500 mg, 1.77 mmol) was dissolved in dioxane / water (10 mL / 1 mL), and furan-2-boric acid (237 mg, 2.12 mmol), potassium carbonate (561 mg, 5.31 mmol), and PdCl2 (dppf) (102 mg, 0.089 mmol) were added. The reaction mixture was stirred overnight at 90 °C. The reaction solution was directly filtered, concentrated under reduced pressure, and purified by reverse-phase column chromatography to obtain 2-(3-bromophenyl)furan (310 mg, yield: 79%), a colorless liquid.

[0382] (2) 2-(3-(furan-2-yl)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaboranecyclopentane

[0383] 2-(3-bromophenyl)furan (200 mg, 0.89 mmol) was dissolved in dioxane solution (10 mL). Under nitrogen atmosphere, bis-pinacol borate (227 mg, 0.89 mmol), potassium acetate (262 mg, 2.67 mmol), and 1,1'-bisdiphenylphosphine ferrocene palladium dichloride (33 mg, 0.05 mmol) were added. The mixture was heated to 90 °C under nitrogen atmosphere and stirred overnight. The reaction solution was used directly in the next step.

[0384] (3) 6-Chloro-3-(3-(furan-2-yl)phenyl)imidazo[1,2-b]pyridazine

[0385] To a 10 mL solution of 2-(3-(furan-2-yl)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborhexacyclopentane in dioxane, 206 mg of 3-bromo-6-chloroimidazolo[1,2-b]pyridazine (0.89 mmol), 33 mg of 1,1'-bis(diphenylphosphine)ferrocene palladium dichloride (0.045 mmol), and 1 mL of water were added. The mixture was heated to 90 °C under nitrogen and stirred overnight. The reaction was monitored by LC-MS until complete. After concentration, the reaction mixture was purified by reverse-phase column chromatography to obtain the target product, 6-chloro-3-(3-(furan-2-yl)phenyl)imidazolo[1,2-b]pyridazine (100 mg, yield: 38%), as a white solid. MS (ESI): m / z 295.9 [M+H] + .

[0386] (4)2-((1r,4r)-4-((3-(3-(furan-2-yl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)prop-2-ol

[0387] 6-Chloro-3-(3-(furan-2-yl)phenyl)imidazo[1,2-b]pyridazine (100 mg, 0.34 mmol), 2-((1r,4r)-4-aminocyclohexyl)propanol (86 mg, 0.68 mmol), and sodium tert-butoxide (98 mg, 1.02 mmol) were dispersed in toluene (5 mL), and BINAP (15 mg, 0.023 mmol) and Pd2(dba)3 (16 mg, 0.017 mmol) were added. The mixture was heated to 90 °C under nitrogen protection and stirred overnight. The reaction mixture was evaporated to dryness, and water (10 mL) was added to the reaction system. The mixture was extracted separately with ethyl acetate (20 mL x 2), dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and purified by Prep-HPLC to give 2-((1r,4r)-4-((3-(3-(furan-2-yl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)prop-2-ol (7.8 mg, yield: 5%), a white solid. MS (ESI): m / z 417.3 [M+H] + . 1 H NMR(400MHz, DMSO-d6)8.63(t,J=1.6Hz,1H),7.97-7.91(m,2H),7.78-7.77(m,1H), 7.74(d,J=10.8Hz,1H),7.68-7.60(m,1H),7.49(t,J=7.6Hz,1H),6.99-6.95(m,1H) ,6.92(d,J=6.8Hz,1H),6.68(d,J=9.6Hz,1H),6.59(q,J=1.6Hz,1H),4.02(s,1H),3 .65-3.58(m,1H),2.21(d,J=6.0Hz,2H),1.83(d,J=11.6Hz,2H),1.23-1.00(m,11H).

[0388] Example 30: 2-((1r,4r)-4-((3-(3-(5-methyl-1,3,4-oxadiazol-2-yl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)propane-2-ol (compound 49)

[0389]

[0390] (1) 2-Methyl-5-(3-(4,4,5,5-tetramethyl-1,3,2-dioxane-2-yl)phenyl)-1,3,4-oxadiazole

[0391] Add 2-(3-bromophenyl)-5-methyl-1,3,4-oxadiazole (400.0 mg, 1.68 mmol), pinacol diborate (414.2 mg, 1.68 mmol), potassium acetate (328.3 mg, 3.36 mol), and [1,1'-bis(diphenylphosphine)ferrocene]palladium dichloride (122.0 mg, 0.17 mmol) to the reaction flask, followed by 8 mL of dioxane. Under nitrogen protection, stir overnight at 90 °C. The reaction mixture is evaporated to dryness to directly give crude 2-methyl-5-(3-(4,4,5,5-tetramethyl-1,3,2-dioxane-2-yl)phenyl)-1,3,4-oxadiazole (480 mg, yield: 99%). MS (ESI): m / z 287.1 [M+H] + .

[0392] (2) 2-(3-(6-chloroimidazole[1,2-b]pyridazin-3-yl)phenyl)-5-methyl-1,3,4-oxadiazole

[0393] 2-Methyl-5-(3-(4,4,5,5-tetramethyl-1,3,2-dioxane-2-yl)phenyl)-1,3,4-oxadiazole (480 mg, 1.68 mmol), 3-bromo-6-chloroimidazole[1,2-b]pyridazine (389.0 mg, 1.68 mmol), tetra(triphenylphosphine)palladium (195.6 mg, 0.17 mmol), and potassium carbonate (460.0 mg, 3.7 mmol) were dissolved in dioxane / water (8 mL / 2 mL). The mixture was stirred overnight at 90 °C under nitrogen protection. The reaction solution was evaporated to dryness and purified by a normal column (PE / EA = 1 / 1) to give 2-(3-(6-chloroimidazole[1,2-b]pyridazine-3-yl)phenyl)-5-methyl-1,3,4-oxadiazole (110 mg, yield: 21%), a yellow solid. MS(ESI): m / z 311.9 [M+H] + .

[0394] (3)2-((1r,4r)-4-((3-(3-(5-methyl-1,3,4-oxadiazol-2-yl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)propane-2-ol

[0395] 2-(3-(6-chloroimidazolo[1,2-b]pyridazin-3-yl)phenyl)-5-methyl-1,3,4-oxadiazole (110 mg, 0.19 mmol), 2-((1r,4r)-4-aminocyclohexyl)propane-2-ol (30.3 mg, 0.19 mmol), tris(dibenzylideneacetone)dipalladium (17.3 mg, 0.02 mmol), sodium tert-butoxide (55.6 mg, 0.58 mmol), and 4,5-bisdiphenylphosphine-9,9-dimethyloxanthracene (22.0 mg, 0.04 mmol) were dissolved in toluene (5 mL). The reaction mixture was stirred overnight at 110 °C. The reaction solution was evaporated to dryness and purified by Pre-HPLC to give 2-((1r,4r)-4-((3-(3-(5-methyl-1,3,4-oxadiazol-2-yl)phenyl)imidazo[1,2-b]pyridazin-6-yl)amino)cyclohexyl)propane-2-ol (5.2 mg, yield: 6.2%), a white solid. MS (ESI): m / z 433.1 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.89(s,1H),8.42(s,1H),8.23(d,J=8.4Hz,1H),8.02-7.98(m,2H),7.74(t,J=8.0Hz,1H),7.55(d,J=6.8Hz,1H),7.09(d,J= 10.0Hz,1H),3.61-3.54(m,1H),2.60(s,3H),2.18(d,J=10.0Hz,2H),1.79 (d,J=12.0Hz,2H),1.22-1.13(m,3H),1.05(d,J=10.8Hz,2H),0.99(s,6H).

[0396] Example 31: 3-(3-(dimethylamino)phenyl)-N-((1-methylpiperidin-4-yl)methyl)imidazo[1,2-b]pyridazin-6-amine (Compound 50)

[0397]

[0398] (1) 3-(6-chloroimidazolo[1,2-b]pyridazin-3-yl)-N,N-dimethylaniline

[0399] Following the method in step (2) of Example 30, 3-bromo-6-chloroimidazolo[1,2-b]pyridazine (100 mg, 0.434 mmol) and (3-(dimethylamino)phenyl)boronic acid (86 mg, 0.521 mmol) were used as raw materials to obtain 3-(6-chloroimidazolo[1,2-b]pyridazine-3-yl)-N,N-dimethylaniline (64 mg, yield: 50.8%), a white solid.

[0400] (2) 3-(3-(dimethylamino)phenyl)-N-((1-methylpiperidin-4-yl)methyl)imidazo[1,2-b]pyridazin-6-amine

[0401] Following the method in step (3) of Example 30, using 3-(6-chloroimidazolo[1,2-b]pyridazin-3-yl)-N,N-dimethylaniline (142 mg, 0.522 mmol) and (1-methylpiperidin-4-yl)methylamine (74 mg, 0.574 mmol) as raw materials, 3-(3-(dimethylamino)phenyl)-N-((1-methylpiperidin-4-yl)methyl)imidazolo[1,2-b]pyridazin-6-amine (7.2 mg, yield: 3.9%) was obtained as a white solid. MS (ESI): m / z 365.4 [M+H] + . 1 H NMR (400MHz, DMSO-d6) δ8.26 (s, 1H), 8.34-8.30 (m, 2H), 7.97-7.95 (d, J = 9.6Hz ,1H),7.64-7.61(m,2H),7.39-7.37(m,1H),7.34-7.30(m,1H),7.05-7.02(m,1H ),6.80-6.78(m,1H),3.46-3.43(m,2H),3.25-3.22(m,2H),2.93(s,6H),2.90- 2.88(m,2H),2.70-2.66(d,J=4.8Hz,3H),2.32-1.72(m,2H),1.40-1.37(m,2H).

[0402] Example 32: 2-[(1r,4r)-4-[[3-(3-methylsulfonylphenyl)imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol (Compound 51)

[0403]

[0404] (1) 6-Chloro-3-(3-methylsulfonylphenyl)imidazo[1,2-b]pyridazine

[0405] Following the method in step (3) of Example 29, 6-chloro-3-iodo-imidazo[1,2-b]pyridazine (200 mg, 715.65 μmol) and (3-methylsulfonylphenyl)boronic acid (171.77 mg, 858.78 μmol) were used as raw materials to obtain 6-chloro-3-(3-methylsulfonylphenyl)imidazo[1,2-b]pyridazine (120 mg, yield: 54.48%), a yellow solid. MS (ESI): m / z 307.9 [M+H] + .

[0406] (2)2-[(1r,4r)-4-[[3-(3-methylsulfonylphenyl)imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol

[0407] Following the method in step (4) of Example 29, using 6-chloro-3-(3-methylsulfonylphenyl)imidazo[1,2-b]pyridazine (60 mg, 194.96 μmol) and 2-((1r,4r)-4-aminocyclohexyl)prop-2-ol (55.18 mg, 350.93 μmol) as raw materials, 2-[(1r,4r)-4-[[3-(3-methylsulfonylphenyl)imidazo[1,2-b]pyridazine-6-yl]amino]cyclohexyl]prop-2-ol (8.5 mg, yield: 10.17%), a white solid, was obtained. MS (ESI): m / z 429.1 [M+H] + . 1 H NMR(400MHz,DMSO-d6)δ8.98(brs,1H),8.33-8.46(m,1H),8.05(d,J=3.06H z,1H),7.66-7.93(m,3H),6.99(d,J=4.77Hz,1H),6.72(dd,J=9.48,3.12Hz, 1H),4.03(d,J=2.93Hz,1H),3.65-3.75(m,1H),3.24(d,J=3.18Hz,3H),2.1 5(s,2H),1.82(d,J=2.08Hz,2H),1.16-1.32(m,4H),1.07(d,J=3.06Hz,6H).

[0408] Example 33: 2-[(1r,4r)-4-[[2-amino-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol (Compound 52)

[0409]

[0410] (1) 6-Chloro-3-iodo-imidazo[1,2-b]pyridazine-2-amine

[0411] At 0°C, N-iodosuccinimide (1.60 g, 7.12 mmol) was added in portions to a solution of 6-chloroimidozolo[1,2-b]pyridazin-2-amine (1 g, 5.93 mmol) in N,N-dimethylformamide (20 mL). After the addition was complete, the reaction mixture was naturally heated to 25°C and stirred at 25°C for 2 hours. The reaction mixture was slowly poured into ice water (50 mL) to quench the reaction, and then extracted with ethyl acetate (30 mL x 3). The organic phases were combined and washed with saturated brine (30 mL). The organic phases were dried over anhydrous sodium sulfate, filtered, and concentrated to dryness to obtain the crude product. The crude product was purified by column chromatography (petroleum ether / ethyl acetate = 50 / 1 to 3 / 1) to give 6-chloro-3-iodo-imidozolo[1,2-b]pyridazin-2-amine (0.6 g, crude product), a brown solid, which was used directly for the next step.

[0412] (2) 6-Chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-2-amine

[0413] At 25°C, [3-(trifluoromethyl)phenyl]boronic acid (212.84 mg, 1.12 mmol), potassium carbonate (281.60 mg, 2.04 mmol), and di-tert-butyl dicarbonate (244.58 mg, 1.12 mmol) were added sequentially to a solution of 6-chloro-3-iodo-imidazo[1,2-b]pyridazine-2-amine (0.3 g, 1.02 mmol) in dioxane (3 mL), followed by purging with nitrogen three times. Then, under nitrogen protection, 1,1-bis(diphenylphosphine)ferrocene palladium chloride (74.54 mg, 101.87 μmol) was added to the reaction solution. After the addition was complete, the system was heated to 80°C and stirred at 80°C for 12 hours. The reaction solution was cooled to 25°C and filtered. The filtrate was concentrated to dryness to obtain the crude product. The crude product was purified by Prep-TLC (100% ethyl acetate) to obtain 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-2-amine (0.1 g, crude product), a yellow solid, which was used directly in the next step.

[0414] (3)2-[(1r,4r)-4-[[2-amino-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol

[0415] At 20°C, 2-((1r,4r)-4-aminocyclohexyl)prop-2-ol (30.18 mg, 191.89 μmol), N,N-diisopropylethylamine (51.67 mg, 399.77 μmol), and cesium fluoride (60.73 mg, 399.77 μmol) were added sequentially to a solution of 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-2-amine (0.05 g, 159.91 μmol) in dimethyl sulfoxide (0.5 mL). The system was heated to 140°C and stirred for 12 hours. The reaction solution was cooled to 20°C and then diluted with water (3 mL). The resulting solution was extracted with ethyl acetate (2 mL x 3), and the combined organic phases were washed with saturated brine (2 mL x 2), dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. The crude product was purified by Prep-HPLC to give 2-[(1r,4r)-4-[[2-amino-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]cyclohexyl]prop-2-ol (0.01 g, yield: 12.78%), a pale yellow solid. MS (ESI): m / z 434.1 [M+H] + . 1 H NMR(400MHz,CD3OD)δ8.27-8.48(m,1H),7.95-8.13(m,1H),7.60-7.82(m,3H),6.84-6.94(m,1H),3 .53-3.69(m,1H),2.18(d,J=10.27Hz,2H),1.86-2.04(m,2H),1.18-1.41(m,5H),1.14-1.17(m,6H).

[0416] Example 34: 4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]bicyclo[2.2.2]oct-1-ol (compound 36)

[0417]

[0418] Following the method in step (1) of Example 7, 4-aminobicyclo[2.2.2]oct-1-ol hydrochloride (21 mg, 120.94 μmol) and 6-chloro-3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine (30 mg, 100.79 μmol) were used as starting materials to obtain 4-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazine-6-yl]amino]bicyclo[2.2.2]oct-1-ol (81 mg, yield: 33.3%), a yellow solid. MS (ESI): m / z 403.2 [M+H] + . 1H NMR(400MHz,DMSO-d6)δ8.59(s,1H),8.33-8.24(m,1H),8.05-7.95(m,1H),7.77-7.66(m,3H ),6.78-6.71(m,1H),6.68-6.59(m,1H),4.34(s,1H),2.12-2.03(m,6H),1.71-1.62(m,6H).

[0419] Example 35: 6-((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)amino)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-2-carbamate (Compound 43)

[0420]

[0421] (1) 3-Bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxylic acid

[0422] Ethyl 3-bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxylic acid (400 mg, 1.32 mmol) was dissolved in tetrahydrofuran / water (8 mL, v / v = 3 / 1), and NaOH (1.81 g, 6.62 mmol) was added. The reaction mixture was stirred at 25 °C for 2 hours. The pH of the reaction mixture was adjusted to 6 with dilute hydrochloric acid, and the solution was evaporated to dryness. The resulting solid was added to methanol (5 mL), stirred, filtered, and the filtrate was evaporated to dryness to obtain 3-bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxylic acid (345 mg, yield: 95%), a white solid, which was used directly in the next step. MS (ESI): m / z 275.9 [M+H] + .

[0423] (2) 3-Bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxamide

[0424] 3-Bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxylic acid (345 mg, 1.25 mmol) and 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (570 mg, 1.50 mmol) were dissolved in N,N-dimethylformamide (10 mL), and N,N-diisopropylethylamine (322 mg, 2.50 mmol) and ammonium chloride (100 mg, 1.88 mmol) were added. The reaction system was stirred at room temperature for 1 hour. Water (10 mL) was added to the reaction system, and the mixture was extracted with ethyl acetate (10 mL x 2). The organic phase was washed with saturated brine (10 mL), dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and purified by reverse-phase column chromatography (acetonitrile / water) to give 3-bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxamide (276 mg, yield: 80.9%), a white solid. MS (ESI): m / z 274.9 [M+H] + .

[0425] (3) 3-Bromo-6-chloroimidazole[1,2-b]pyridazine-2-carbamate

[0426] 3-Bromo-6-chloroimidazole[1,2-b]pyridazine-2-carboxamide (276 mg, 1.01 mmol) was dissolved in dichloromethane (5 mL), and N-(triethylammonium sulfonyl)carbamate (1.24 g, 5.05 mmol) was added. The reaction mixture was stirred at 25 °C for 16 hours. The reaction solution was evaporated to dryness and purified by reverse-phase column chromatography (acetonitrile / water) to give 3-bromo-6-chloroimidazole[1,2-b]pyridazine-2-carbocyanide (86 mg, yield: 33.4%), a white solid. MS (ESI): m / z 256.9 [M+H] + .

[0427] (4) 3-Bromo-6-((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)aminoimidazolium[1,2-b]pyridazine-2-carbamate

[0428] 3-Bromo-6-chloroimidazole[1,2-b]pyridazine-2-carbamate (86 mg, 0.33 mmol) was dissolved in dimethyl sulfoxide (5 mL), and 2-((1r,4r)-4-aminocyclohexyl)propane-2-ol (58 mg, 0.37 mmol), triethylamine (68 mg, 0.62 mmol), and cesium fluoride (102 mg, 0.67 mmol) were added. The reaction mixture was stirred at 110 °C for 16 hours. Water (5 mL) was added to the reaction system, and the mixture was extracted separately with ethyl acetate (10 mL x 2). The organic phase was washed with saturated brine (10 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give 3-bromo-6-((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)aminoimidazolium[1,2-b]pyridazine-2-carbamate (90 mg, yield: 70.8%), a white solid. MS (ESI): m / z 378.1 [M+H] + .

[0429] (5)6-((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)amino)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-2-carbamate

[0430] 3-Bromo-6-((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)aminoimidazolium[1,2-b]pyridazine-2-carbamate (90 mg, 0.23 mmol) and (3-(trifluoromethyl)phenyl)boronic acid (49 mg, 0.26 mmol) were dissolved in 1,4-dioxane / water (4 mL, v / v = 3 / 1). [1,1'-bis(diphenylphosphine)ferrocene]palladium dichloride (17 mg, 0.02 mmol) and potassium carbonate (65 mg, 0.47 mmol) were added to the solution. The reaction mixture was stirred overnight. After removing the solvent, the crude product was directly purified by reverse column chromatography. Pre-HPLC purification of the crude product yielded 6-((1r,4r)-4-(2-hydroxypropane-2-yl)cyclohexyl)amino)-3-(3-(trifluoromethyl)phenyl)imidazo[1,2-b]pyridazine-2-carbamate (9.2 mg, yield: 8.7%), a white solid. MS (ESI): m / z 444.2 [M+H] + . 1H NMR(400MHz, DMSO-d6)δ8.55(s,1H),8.22(d,J=8.8Hz,1H),7.89-7.84(m,3H),7.44-7.42(d,J=8.4Hz,1H),6.95-6.91(d, J=13.6Hz,1H),4.07(s,1H),3.50(br,1H),2.11(d,J=13.6Hz,2H),1.85(d,J=15.2Hz,2H),1.24-1.10(m,5H),1.05(s,6H).

[0431] Other compounds were prepared using the same process route described above.

[0432] Test Example 1: PIM1 / 2 / 3 Kinase Activity Assay

[0433] 1. Experimental Methods

[0434] The PIM1 / 2 / 3 activity of the compound was tested using the Mobility Shift Assay method. The specific method is as follows: the compound to be tested was dissolved in DMSO to prepare a 10 mM stock solution. The initial concentration of the compound for testing was 10 μM, and it was diluted 3 times to obtain 10 concentrations.

[0435] The positive control drug TP-3654 was commercially available or prepared according to Example 31 of patent WO2013013188.

[0436] Prepare kinase solutions of PIM1, PIM2, and PIM3 (all three kinases were from Carna) at a final concentration of 2.5x using 1×Kinase buffer. Add 10 μl of the 2.5x final concentration of kinase solution to each compound well and positive control well, and 10 μl of 1×Kinase buffer to each negative control well. Centrifuge at 1000 rpm for 30 seconds, vortex to mix, and incubate at room temperature for 10 minutes. Prepare a 25 / 15x final concentration mixture of ATP and Kinase substrate 20 (from GL) using 1×Kinase buffer. Add 15 μl of the 25 / 15x final concentration mixture of ATP and Kinase substrate 20 to start the reaction. Centrifuge the 384-well plate at 1000 rpm for 30 seconds, vortex to mix, and incubate at room temperature for 60 minutes. Add 30 μl of stop assay solution to stop the kinase reaction, centrifuge at 1000 rpm for 30 seconds, and vortex to mix. Read the conversion rate using a Caliper EZ Reader.

[0437] 2. Result Calculation

[0438] The IC50 values ​​of each test compound for enzyme activity were obtained by fitting dose-response curves using the analysis software GraphPad Prism 5. The results for each compound are shown in Table 1, where A+ indicates <2nM, A indicates 2-10nM, B indicates 10-100nM, C indicates 100-1000nM, D indicates 1000-10000nM, and E indicates >10000nM.

[0439] Table 1 Results of PIM1 / 2 / 3 kinase activity assay

[0440]

[0441] Test Example 2: Cell Inhibitory Activity Test

[0442] The EPOR-JAK2-V617F gene was transferred into Ba / F3 wild-type cells using a retroviral packaging system to obtain a stable cell line, Ba / F3-EPOR-JAK2-V617F, which was used to inhibit the cellular activity of the compound IC50. 50 Test (Reference: Blood. 2010; 115(15):3109-3117). The specific method is as follows:

[0443] Cells were seeded in 96-well plates and treated with the test compound (0.2% final DMSO concentration) from the DMSO stock solution. After incubation at 37°C and 5% CO2 for 72 hours, cell proliferation inhibition activity was detected using the CTG (Cell-Titer Globe) method. The initial concentration of the compound was 10 μM, with 3-fold dilutions, resulting in 9 concentrations. Dose-response curves were fitted using Graphpad 7.0 software, and IC50 was obtained. 50 value.

[0444] The results showed that most compounds exhibited cell-inhibiting activities stronger than or equivalent to the PIM inhibitor TP-3654. The IC50 values ​​of the cell-inhibiting activities of some preferred compounds were also shown. 50 Significantly superior to the PIM inhibitor TP-3654 (TP-3654 was prepared according to Example 31 of patent WO2013013188) (significantly superior by an exponential order of magnitude). Results for some tested compounds are shown in Table 2, where ++++ indicates 0-50 nM, +++ indicates 50-100 nM, ++ indicates 100-150 nM, and + indicates >150 nM.

[0445] Table 2. Results of Cell Inhibition Activity Tests

[0446]

[0447] Test Example 3: Pharmacokinetic Study

[0448] 1. Experimental Methods

[0449] Experimental animals: BALB / c mice, female; weight: 19-25g.

[0450] Test sample preparation: Prepare the target compound into 0.4 mg / mL (for intravenous administration) and 5.0 mg / mL (for oral administration) solutions for later use. Route of administration: Oral / intravenous injection. Dosage volume and frequency: 5 mL / kg (intravenous injection) or 10 mL / kg (oral), single dose.

[0451] Sample collection: Blood samples were collected at the following time points: 5 min, 15 min, 30 min, 1 hr, 2 hr, 4 hr, 8 hr and 24 hr after drug administration.

[0452] 2. Sample Analysis and Results

[0453] Sample analysis: The collected samples were analyzed using LC-MS / MS. The instrument used was an ABSciex 5500.

[0454] Pharmacokinetic data analysis: The obtained blood drug concentration data were fitted and calculated using the non-compartmental model method, and some results are summarized in Table 3.

[0455] Table 3 Results of pharmacokinetic studies

[0456]

[0457] Note: 1. The intravenous administration formulation is: 10% DMSO / 50% PEG400 / 40% (23% HPBCD);

[0458] 2. The oral formulations are: 10% Tween20 + 90% (0.5% MC) (compounds 29, 46 and TP-3654) and 5% Tween20 + 5% solubil + 90% (0.5% MC) (compound 20).

[0459] Experimental results show that the compound of the present invention has good pharmacokinetic characteristics, and the drug exposure (C0.05) of the compound in animals after oral administration was measured. max Both the AUC and the bioavailability of the tested compound were higher than those of TP-3654, indicating that the bioavailability of the tested compound was higher than that of TP-3654.

[0460] In addition, the toxic side effects of the compounds of this invention were tested. Once-daily administration to nude mice for 30 consecutive days showed that the compounds of this invention have low toxic side effects and are well tolerated in animals; the highest tested dose was 150 mg / kg / day.

[0461] Unless otherwise specified, the terms used in this invention have the meanings commonly understood by those skilled in the art.

[0462] The embodiments described in this invention are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art can make various other substitutions, changes and improvements within the scope of this invention. Therefore, this invention is not limited to the above embodiments, but is only defined by the claims.

Claims

1. A compound having the structure shown below, its deuterated form, stereoisomer, or pharmaceutically acceptable salt: 。 2. A pharmaceutical composition comprising the compound according to claim 1, a deuterated form thereof, a stereoisomer thereof, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier thereof.

3. Use of the compound of claim 1, its deuterated form, stereoisomer, or pharmaceutically acceptable salt, or the pharmaceutical composition of claim 2 in the preparation of a medicament for treating and / or preventing PIM-related diseases.

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