Stat3 / hdac dual-target inhibitor, composition and application thereof

Abstract

The application discloses a STAT3 / HDAC dual-target inhibitor, a composition and application thereof. A variety of biological experiments prove that the compound has excellent anti-proliferation activity on a variety of cancer cells, has STAT3 and HDAC dual inhibition activity, and has the functions of regulating Ser727 and Tyr705 phosphorylation, and can be used as a STAT3 / HDAC dual-target inhibitor to prepare an anti-tumor and other STAT3 related disease treatment, and has a good application prospect.

Description

Technical Field

[0001] This invention belongs to the field of medicinal chemistry, specifically relating to a STAT3 / HDAC dual-target inhibitor, its composition, and its applications. Background Technology

[0002] Signal transducer and activator of transcription 3 (STAT3), a non-enzymatic protein with dual functions as an intracellular signal transducer and transcription factor, is continuously activated in approximately 70% of human cancers. STAT3 plays a crucial role in multiple oncogenic pathways and has long been considered a highly promising target for cancer therapy. However, the development of STAT3 inhibitors faces significant challenges due to the lack of typical small-molecule binding pockets inherent to transcription factors.

[0003] Within the structural motif of STAT3, the SH2 domain is involved in initiating the transcription of target genes. Given the indispensable role of the SH2 domain in STAT3 activation and dimerization, small molecule compounds targeting this domain dominate the development of STAT3 inhibitors. Currently, inhibitors targeting the SH2 domain face limitations in further development due to limited efficacy, and most of these inhibitors only interfere with the classic STAT3 activation mechanism by blocking Tyr705 phosphorylation, failing to inhibit Ser727 phosphorylation.

[0004] Unlike Tyr705 phosphorylation, Ser727 phosphorylation mediates oncogenicity through non-canonical STAT3 function. In addition to enhancing the canonical transcriptional function of STAT3, Ser727 phosphorylation also promotes the interaction between STAT3 and GRIM-19, regulates mitochondrial oxidative phosphorylation (OXPHOS), promotes ATP production, and increases oxygen consumption. Ser727 phosphorylation is one of the important causes of RAS-mediated tumorigenesis.

[0005] Given the complementary roles of Tyr705 and Ser727 phosphorylation in cancer development and progression, developing STAT3 inhibitors that simultaneously inhibit both phosphorylation levels holds promise for enhancing anti-tumor efficacy. Although dual-site phosphorylation inhibitors of Tyr705 and Ser727 show greater promise than Tyr705 phosphorylation inhibitors, studies have shown that inhibiting STAT3 phosphorylation alone is insufficient to fully block its function. Furthermore, dual-site phosphorylation inhibitors of Tyr705 and Ser727 have exhibited insufficient anti-tumor activity in clinical trials. Therefore, effective strategies are urgently needed to further enhance the anti-tumor function of dual-site phosphorylation inhibitors.

[0006] Histone deacetylases (HDACs) are a classic class of epigenetic regulatory proteins. Their abnormal activation is closely related to the occurrence, development, invasion, and metastasis of various malignant tumors, such as prostate cancer, colorectal cancer, breast cancer, lung cancer, cutaneous T-cell lymphoma, multiple myeloma, and malignant melanoma. Currently, the US FDA and NMPA have approved five HDAC inhibitors for the treatment of malignant tumors. Although these drugs have shown significant anti-tumor activity against various hematologic malignancies, their efficacy in treating solid tumors is poor.

[0007] The occurrence and development of tumors is a complex pathological process involving multiple factors, multiple targets, and multiple signaling pathways. Single-target inhibitors suffer from insufficient efficacy and frequent drug resistance in clinical applications. Multi-target drugs designed based on the concept of "polyphacology" offer a new approach to address these issues. Developing single-molecule / dual (multi-target) inhibitors that simultaneously intervene in the functions of HDACs and other key oncogenic proteins to achieve synergistic anticancer efficacy has become a feasible strategy to improve the therapeutic effect of single-target drugs and overcome drug resistance. In recent years, various single-molecule / dual (multi-target) inhibitors that simultaneously intervene in the JAK-STAT3 pathway and HDACs have been reported, including JAK / HDAC inhibitors, STAT3 / HDAC inhibitors, and JAK / HDAC / BRD4 inhibitors. However, to date, no STAT3 / HDAC dual-target inhibitors with both Ser727 and Tyr705 phosphorylation regulation functions have been reported. Such molecules can maximally and directly intervene in STAT3 function while simultaneously addressing the insufficient efficacy of inhibiting STAT3 alone. Summary of the Invention

[0008] To address the shortcomings of existing STAT3 inhibitors in antitumor efficacy, this invention aims to provide a STAT3 / HDAC dual-target inhibitor, its composition, and its applications. Multiple biological experiments have confirmed that the compound of this invention possesses dual inhibitory effects on STAT3 and HDAC, while also regulating Ser727 and Tyr705 phosphorylation, and exhibiting significant antitumor activity.

[0009] This invention is achieved through the following technical solution:

[0010] On one hand, the present invention provides a STAT3 / HDAC dual-target inhibitor, characterized in that the STAT3 / HDAC dual-target inhibitor has compounds as shown in formulas I-V or their pharmaceutically acceptable salts or deuterated derivatives.

[0011]

[0012] In the above formula: X is independently selected from -(CH2)n1-, where n1 = 1-7;

[0013] Ring A is independently selected from aryl or five-membered heteroaryl;

[0014] Ring B is independently selected from -CONHR1;

[0015] The ring C is independently selected from -COR2 or R3;

[0016] Wherein, R1 is independently selected from at least a six-membered nitrogen-containing monoacid heterocyclic group or a seven- to nine-membered diazaspirocyclic group; R 2、 R3 may be the same or different, and each is independently selected from at least aryl or five- to six-membered heteroaryl groups.

[0017] In some preferred embodiments of the present invention, n1 = any one of 1, 3 or 7.

[0018] In certain preferred embodiments of the present invention, X is independently selected from -CH2-; cycloatom A is independently selected from either phenyl or thiophene.

[0019] In certain preferred embodiments of the present invention, X is independently selected from -CH2-; R1 is independently selected from any one of piperazine, 2,6-diazaspiro[3.3]heptyl, 2,6-diazaspiro[3.4]octyl or 2,7-diazaspiro[4.4]nonyl.

[0020] In certain preferred embodiments of the present invention, R2 is independently selected from any one of phenyl, thiophene or pyridinyl, and R3 is independently selected from pyrimidinyl.

[0021] In certain preferred embodiments of the present invention, the STAT3 / HDAC dual-target inhibitor is selected from any of the following compounds or their pharmaceutically acceptable salts or deuterates:

[0022]

[0023] In another aspect, the present invention also provides a pharmaceutical composition comprising an effective amount of a STAT3 / HDAC dual-target inhibitor as shown in Formula I-V or a pharmaceutically acceptable salt or deuterated thereof, and at least one pharmaceutically acceptable carrier or excipient.

[0024] In some preferred embodiments of the invention, the pharmaceutical composition further includes at least one other therapeutic agent, which is an immunotherapeutic agent.

[0025] The dosage form of the pharmaceutical composition described in this invention is any clinically or pharmaceutically acceptable dosage form, such as tablets, granules, capsules, injections, oral liquids, syrups, suppositories, transdermal preparations, and other conventional pharmaceutical formulations.

[0026] Finally, the present invention also provides the use of STAT3 / HDAC dual-target inhibitors as shown in Formulas I-V, or pharmaceutically acceptable salts or deuterated derivatives thereof, or pharmaceutical compositions thereof, in the preparation of antitumor drugs.

[0027] The tumors described in this invention include solid tumors and hematologic tumors, including but not limited to breast cancer, cervical cancer, colon cancer, pancreatic cancer, esophageal squamous cell carcinoma, non-small cell lung cancer, ovarian cancer, lymphoma, acute myeloid leukemia, and chronic myeloid leukemia.

[0028] The dosage of the compound of this invention is 1 mg-1000 mg / day, but may deviate from this range depending on the severity of the condition or the dosage form.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] This invention provides a class of STAT3 / HDAC dual-target inhibitors. Through various biological experiments, it has been confirmed that these compounds have excellent anti-proliferative activity against a variety of cancer cells. They also have dual inhibitory activity against STAT3 and HDAC, and can regulate the phosphorylation of Ser727 and Tyr705. They can be used as STAT3 / HDAC dual-target inhibitors for the preparation of anti-tumor and other STAT3-related disease treatments, and have good application prospects. Attached Figure Description

[0031] Figure 1 Effects of compound 17 on phosphorylation of STAT3 Tyr705 and Ser727 sites in HCT-116 cells: (A) Expression levels of p-STAT3 Tyr705 and p-STAT3 Ser727 after treatment with compound 17 or OPB-31121; (B) Quantitative results of Western blot (WB) bands (results are expressed as mean ± standard deviation, n = 3, *p<0.05, **p<0.01, ***p<0.001 VS blank control).

[0032] Figure 2 The dose-response curves of compound 17 and OPB-31121 inhibiting ATP production are shown.

[0033] Figure 3 Effects of compound 17 on mitochondrial function in HCT-116 cells: (A) Inhibition of OXPHOS in mitochondria of HCT-116 cells by compound 17; (BD) Inhibition of basal OCR, maximum OCR and mitochondrial ATP production by compound 17 in HCT-116 cells (Results are expressed as mean ± standard deviation, n = 3, **p<0.01 VS blank control).

[0034] Figure 4 Effects of compound 17 on H3 and α-tubulin deacetylation in HCT-116 cells: (A) Expression levels of Ac-H3 and Ac-α-tubulin after treatment with compound 17 or OPB-31121; (B) Quantitative results of WB bands (results are expressed as mean ± standard deviation, n = 3, *p<0.05 VS blank control).

[0035] Figure 5 Effects of compound 17 on the cell cycle of HCT-116 cells: Effects of treatment with compound 17, OPB-31121, or SAHA on cell cycle distribution.

[0036] Figure 6 Effect of compound 17 on apoptosis in HCT-116 cells: Effects of compound 17, OPB-31121 or SAHA treatment on apoptosis.

[0037] Figure 7 Bar chart showing the effects of treatment with (AB) compound 17, OPB-31121, or SAHA on cell cycle arrest, S phase, and apoptosis. (Results are expressed as mean ± standard deviation, n = 3, *) p <0.05,** p <0.01, *** p <0.001, **** p <0.0001 VS blank control). Detailed Implementation

[0038] Unless otherwise defined, all technical terms herein have the same meaning as commonly understood by one of ordinary skill in the art to which the subject matter of the claims pertains.

[0039] In this application, "aryl" refers to a monocyclic or fused polycyclic ring having 6 to 14 carbon atoms and possessing a fully conjugated π-electron system. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, anthracene, phenanthryl, fluorenyl, 2,3-dihydro-1H-isoindolyl, 2-benzoxazolinone, 2H-1,4-benzoxazin-3(4H)-one-7-yl, etc.

[0040] "Five- to six-membered heteroaryl groups" refer to non-all-carbon monocyclic or fused polycyclic groups with 5 to 6 ring atoms, possessing a fully conjugated π-electron system. Examples of five- to six-membered heteroaryl groups include, but are not limited to, pyridyl, imidazolyl, pyrimidinyl, thiophene, furanyl, and thiazolyl.

[0041] "Six-membered nitrogen-containing monoacid heterocyclic group" refers to a monocyclic saturated heterocyclic group with 6 ring atoms in which at least one nitrogen atom is substituted. Examples of six-membered nitrogen-containing monoacid heterocyclic groups include, but are not limited to, piperidinyl and piperazine groups.

[0042] "Seven- to nine-membered diazaspirocyclic groups" refers to diazaspirocyclic systems with 7 to 9 ring atoms. This system consists of two monocyclic rings connected by a shared spiro atom, and the ring skeleton contains two nitrogen atoms. Examples of seven- to nine-membered diazaspirocyclic groups include, but are not limited to, 2,6-diazaspiro[3.3]heptyl, 2,6-diazaspiro[3.4]octyl, 2,7-diazaspiro[4.4]nonyl, 2,6-diazaspiro[3.4]octyl, 2,7-diazaspiro[3.5]nonyl, and 2,7-diazaspiro[3.5]nonyl.

[0043] The compounds of the present invention or their pharmaceutically acceptable salts or deuterated derivatives have the same efficacy, wherein the pharmaceutically acceptable salts are salts of the above general formulas (I-V), and wherein the pharmaceutically acceptable salts are hydrochloride, sulfate, phosphate, maleate, fumarate, citrate, methanesulfonate, tartrate, sodium or potassium salts.

[0044] In this application, the term "pharmaceutical carrier" refers to conventional drug carriers in the pharmaceutical field, including conventional diluents, excipients (such as water), fillers (such as starch), binders (such as cellulose derivatives, gelatin, etc.), humectants (such as glycerin, etc.), disintegrants (such as agar, calcium carbonate, etc.), absorption enhancers (such as quaternary ammonium compounds, etc.), surfactants (such as hexadecyl alcohol, etc.), adsorbent carriers (such as kaolin and soap clay, etc.), lubricants (such as talc, etc.), and flavoring agents, sweeteners, etc. may be added when necessary.

[0045] In this application, the term "any pharmaceutically acceptable dosage form" applies to administration via any suitable route, such as oral (including sublingual or sublingual), rectal, nasal, topical (including sublingual, sublingual, or transdermal), vaginal, or parenteral (including subcutaneous, intramuscular, intravenous, or intradermal) administration. These formulations can be prepared by any method known in the field of pharmaceutical science. For example, methods involving mixing the active ingredient with a carrier or excipient.

[0046] In this application, the term "effective amount" means an amount of at least one pharmaceutical agent or compound that, when taken orally, is sufficient to alleviate one or more symptoms of the disease or condition being treated to a certain extent. For example, an "effective amount" for treatment is the amount of a compound or composition disclosed herein that is clinically necessary to provide significant symptom relief.

[0047] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0048] The reagents and raw materials used in this invention are all commercially available.

[0049] Taking compounds 1 (Route I), 6 (Route II), 10 (Route III), 11 (Route IV), 12 (Route V), and 16 (Route VI) as examples, the compound preparation methods of the present invention are as follows:

[0050] In addition, compounds 2-5 were prepared according to route I; compounds 7-9 according to route II; compounds 13-15 according to route V; and compound 17 according to route VI. It should be noted that the specific examples included below are for illustrative purposes only and should not be construed as limiting the scope of the invention. Furthermore, it should be understood that after reading the contents of this invention, those skilled in the art can make various alterations or modifications to the invention, and such equivalent forms also fall within the scope defined by the appended claims.

[0051] Route I:

[0052]

[0053] In Route I, the reactants and reaction conditions involved are as follows:

[0054] a is Boc₂O, dichloromethane (DCM), 0 °C to room temperature (rt);

[0055] b is 2-chloro-5-nitropyridine, K2CO3, N,N-dimethylformamide (DMF), 65 ℃;

[0056] c is NaH, CH3I, anhydrous DMF, 0 ℃ to rt;

[0057] d is (1) trifluoroacetic acid (TFA), DCM, 0 °C to rt; (2) ethyl bromoacetate, Cs2CO3, KI, anhydrous acetonitrile (CH3CN), N2 protection, 70 °C;

[0058] e is (1) Zn, acetic acid (HOAc), N2 protection, 50 ℃; (2) 4-(trifluoromethyl)benzoic acid, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI), 1-hydroxybenzotriazole (HOBt), triethylamine (TEA), DCM, rt;

[0059] f is NH2OH (50% in H2O), NaOH, tetrahydrofuran (THF) / methanol (MeOH), 0 °C to rt.

[0060] Route II:

[0061]

[0062] In Route II, the reactants and reaction conditions involved are as follows:

[0063] a is N-Boc-piperazine, TBD, THF, N2 protection, reflux;

[0064] b is (1) TFA, DCM, 0 ℃ to rt; (2) methyl 2-chloropyrimidine-5-carboxylate, Cs2CO3, KI, anhydrous CH3CN, N2 protection, 70 ℃;

[0065] c is NH2OH (50% in H2O), NaOH, THF / MeOH, 0 ℃ to rt.

[0066] Route III:

[0067]

[0068] In Route III, the reactants and reaction conditions involved are as follows:

[0069] a is (1) TFA, DCM, 0 ℃ to rt; (2) methyl-2-(4-(((methanesulfonyl)oxo)methyl)piperidin-1-yl)pyrimidine-5-carboxylic acid ester, Cs2CO3, KI, anhydrous CH3CN, N2 protected, 70 ℃;

[0070] b is (1) Zn, HOAc, N2 protection, 50 ℃; (2) 4-(trifluoromethyl)benzoic acid, EDCI, HOBt, TEA, DCM, rt;

[0071] c is NH2OH (50% in H2O), NaOH, THF / MeOH, 0 ℃ to rt.

[0072] Route IV:

[0073]

[0074] In Route IV, the reactants and reaction conditions involved are as follows:

[0075] a is (1) TFA, DCM, 0 ℃ to rt; (2) N-Boc-4-piperidinone, HAc, NaBH(OAc)3, DCM, rt;

[0076] b is (1) Zn, HOAc, N2 protection, 50 ℃; (2) 4-(trifluoromethyl)benzoic acid, EDCI, HOBt, TEA, DCM, rt;

[0077] c is (1) TFA, DCM, 0 ℃ to rt; (2) methyl 2-chloropyrimidine-5-carboxylate, Cs2CO3, KI, anhydrous CH3CN, N2 protection, 70 ℃;

[0078] d is NH2OH (50% in H2O), NaOH, THF / MeOH, 0 ℃ to rt.

[0079] Route V:

[0080]

[0081] In route V, the reactants and reaction conditions involved are as follows:

[0082] a is (1) TFA, DCM, 0 ℃ to rt; (2) 1-BOC-4-methanesulfonyloxymethylpiperidine, Cs2CO3, KI, anhydrous DMF, N2 protection, 95 ℃.

[0083] b is (1) Zn, HOAc, N2 protection, 50 ℃; (2) 4-(trifluoromethyl)benzoic acid, EDCI, HOBt, TEA, DCM, rt;

[0084] c is (1) TFA, DCM, 0 ℃ to rt; (2) Monomethyl terephthalate, EDCI, HOBt, TEA, DCM, rt;

[0085] d is NH2OH (50% in H2O), NaOH, THF / MeOH, 0 ℃ to rt.

[0086] Route VI:

[0087]

[0088] In Route VI, the reactants and reaction conditions involved are as follows:

[0089] a is (1) TFA, DCM, 0 ℃ to rt; (2) 5-(methoxycarbonyl)-2-pyridinecarboxylic acid, EDCI, HOBt, TEA, DCM, rt;

[0090] b is NH2OH (50% in H2O), NaOH, THF / MeOH, 0 ℃ to rt.

[0091] Example 1: Synthesis of N-[6-[4-[2-(hydroxyamino)-2-oxoethylamino]-2-methylphenoxy]pyridin-3-yl]-4-(trifluoromethyl)benzamide (Compound 1)

[0092] (1) Synthesis of tert-butyl (4-hydroxy-3-methylphenyl)carbamate (intermediate 19)

[0093]

[0094] Add 18 (1.2 g, 9.75 mmol, 1.0 eq) and DCM (20 mL) to a two-necked flask. Add Boc₂O (2.46 mL, 10.73 mmol, 1.1 eq) dropwise under ice bath conditions. After the addition is complete, move the mixture to room temperature. Once the reaction is complete as shown by TLC, neutralize with saturated NaHCO₃ solution, extract with EA, and wash successively with saturated NaHCO₃ solution, water, and saturated NaCl solution. Combine the organic phases, dry over anhydrous Na₂SO₄, concentrate under reduced pressure, and precipitate the crude product by silica gel column chromatography to obtain 1.5 g of a pale red solid.

[0095] Yield 69%. 1 H NMR (400 MHz, DMSO-d6): δ 8.87 (s, 2H), 7.13 (s, 1H), 7.04-6.97 (m, 1H), 6.63 (d, J = 8.8 Hz, 1H), 2.06 (s, 3H), 1.44 (s, 9H). ESI-MS m / z: 224 [M+H] + .

[0096] (2) Synthesis of tert-butyl (3-methyl-4-((5-nitropyridin-2-yl)oxy)phenyl)carbamate (intermediate 20)

[0097]

[0098] Intermediate 19 (1.5 g, 6.72 mmol, 1.0 eq), 2-chloro-5-nitropyridine (1.60 g, 10.08 mmol, 1.5 eq), K₂CO₃ (1.86 g, 13.44 mmol, 2.0 eq), and anhydrous DMF (20 mL) were added sequentially to a round-bottom flask, and the mixture was heated to 65 °C. After the reaction was confirmed to be complete by TLC, the mixture was extracted with EA and washed sequentially with saturated NaHCO₃ solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na₂SO₄, concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography to obtain 1.73 g of a pale yellow solid.

[0099] Yield 75%. 1H NMR (400 MHz, DMSO-d6): δ 9.38 (s, 1H), 9.00 (d, J =2.8 Hz, 1H), 8.60 (dd, J = 9.2, 2.8 Hz, 1H), 7.45 (d, J = 2.5 Hz, 1H), 7.30(dd, J = 8.7, 2.8 Hz, 1H), 7.20 (d, J = 9.2 Hz, 1H), 7.02 (d, J = 8.8 Hz,1H), 2.01 (s, 3H), 1.48 (s, 9H). ESI-MS m / z: 346 [M+H] + .

[0100] (3) Synthesis of methyl (3-methyl-4-[(5-nitropyridin-2-yl)oxy]phenyl)carbamate tert-butyl ester (intermediate 21)

[0101]

[0102] Intermediate 20 (1.73 g, 5.01 mmol, 1.0 eq), NaH (60%, 300.56 mg, 12.52 mmol, 2.5 eq), and anhydrous DMF (20 ml) were added sequentially to two-necked flasks. The mixture was reacted under N2 protection in an ice bath for 0.5 h. Subsequently, CH3I (659 μL, 10.02 mmol, 2.0 eq) was added, and the reaction was moved to room temperature. After TLC showed that the reaction was complete, saturated NH4Cl solution was added to quench the reaction. The mixture was extracted with EA and washed successively with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography to obtain 1.39 g of a pale yellow solid.

[0103] Yield 84%. 1 H NMR (400 MHz, DMSO-d6): δ 9.02 (d, J = 2.8 Hz, 1H), 8.63 (dd, J = 9.2, 2.8 Hz, 1H), 7.30-7.23 (m, 2H), 7.18 (dd, J = 8.8, 2.7 Hz, 1H), 7.11 (d, J = 8.6 Hz, 1H), 3.20 (s, 3H), 2.06 (s, 3H), 1.41 (s, 8H). ESI-MS m / z: 360 [M+H] + .

[0104] (4) Synthesis of N-methyl-N-[3-methyl-4-[(5-nitropyridin-2-yl)oxy]phenyl]glycine ethyl ester (intermediate 22a)

[0105]

[0106] Intermediate 21 (1.22 g, 3.18 mmol, 1.0 eq) and DCM (16 mL) were added to a round-bottom flask. TFA (4 mL) was added dropwise under ice bath. After the addition was complete, the mixture was moved to room temperature. After the TLC showed that the reaction was complete, saturated NaHCO3 solution was added to quench the reaction. The mixture was extracted with EA and washed successively with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, and concentrated under reduced pressure to give a pale red solid, which was used directly in the next step without purification.

[0107] The above product (390 mg, 1.50 mmol, 1.0 eq), ethyl bromoacetate (500 μL, 4.51 mmol, 3.0 eq), KI (249.7 mg, 1.50 mmol, 1.0 eq), Cs₂CO₃ (1.2 g, 3.76 mmol, 2.5 eq), and anhydrous CH₃CN (8 mL) were added sequentially to a two-necked flask. The mixture was heated to 70 °C under N₂ protection. After the reaction was complete as shown by TLC, the mixture was extracted with EA and washed sequentially with saturated NaHCO₃ solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na₂SO₄, concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography to obtain 440.7 mg of a pale yellow solid.

[0108] Yield 84% for two steps. 1 H NMR (400 MHz, CDCl3): δ 9.01 (d, J = 2.8Hz, 1H), 8.58 (dd, J = 9.2, 2.8 Hz, 1H), 7.14 (d, J = 9.2 Hz, 1H), 6.93 (d, J= 8.8 Hz, 1H), 6.62 (d, J = 2.8 Hz, 1H), 6.54 (dd, J = 8.8, 3.2 Hz, 1H), 4.20(s, 2H), 4.14-4.10 (m, 2H), 2.99 (s, 3H), 2.00 (s, 3H), 1.21-1.17 (m, 3H).ESI-MS m / z: 346 [M+H] + .

[0109] (5) Synthesis of N-methyl-N-[3-methyl-4-[(5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy]phenyl]glycine ethyl ester (intermediate 23a)

[0110]

[0111] Intermediate 22a (440 mg, 1.27 mmol, 1.0 eq) and HOAc (9 ml) were added to a round-bottom flask, followed by Zn powder (1.25 g, 19.11 mmol, 15.0 eq). The mixture was heated at 50 °C under N2 protection. After TLC showed complete reaction, the zinc powder was removed by filtration. The filtrate was extracted with EA and washed successively with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, and concentrated under reduced pressure. The unpurified solution was used directly in the next step.

[0112] To a round-bottom flask, p-trifluorobenzoic acid (363.3 mg, 1.91 mmol, 1.5 eq), EDCI (366.3 mg, 1.91 mmol, 1.5 eq), HOBt (258.2 mg, 1.91 mmol, 1.5 eq), and DCM (9 mL) were added sequentially, and the mixture was stirred at room temperature for 0.5 h. Then, an unpurified intermediate (401.8 mg, 1.27 mmol, 1.0 eq) and TEA (530 μL, 3.82 mmol, 3.0 eq) were added, and the mixture was stirred at room temperature again. After TLC showed complete reaction, the mixture was extracted with EA, washed sequentially with NaHCO3 solution, water, and saturated NaCl solution, the organic phases were combined, dried over anhydrous Na2SO4, concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography to obtain 447.4 mg of a pale yellow solid.

[0113] Yield 77% for two steps. 1H NMR (600 MHz, DMSO-d6): δ 10.57 (s, 1H), 8.42 (d, J = 2.4 Hz, 1H), 8.19-8.11 (m, 3H), 7.92 (d, J = 7.8 Hz, 2H), 6.92(d, J = 9.0 Hz, 1H), 6.87 (d, J = 9.0 Hz, 1H), 6.59 (d, J = 2.4 Hz, 1H), 6.51 (dd, J = 9.0, 3.0 Hz, 1H), 4.18 (s, 2H), 4.11 (q, J = 7.2 Hz, 2H), 2.98 (s,3H), 2.02 (s, 3H), 1.19 (t, J = 7.2 Hz, 3H). ESI-MS m / z: 430 [M+H] + .

[0114] (6) Synthesis of N-[6-[4-[2-(hydroxyamino)-2-oxoethylamino]-2-methylphenoxy]pyridin-3-yl]-4-(trifluoromethyl)benzamide (compound 1)

[0115]

[0116] NH₂OH (50% in H₂O, 1 mL) and NaOH (131.3 mg, 1.64 mmol, 8.0 eq) were added to a round-bottom flask. Then, under ice bath conditions, intermediate 23a (200 mg, 0.41 mmol, 1.0 eq), dissolved in THF:MeOH (V:V = 1:1, 2 mL), was added dropwise to the hydroxylamine solution. After the addition was complete, the mixture was allowed to return to room temperature. Once the reaction was complete as indicated by TLC, the pH was adjusted to 7 with HOAc, and the mixture was concentrated under reduced pressure to remove THF and MeOH. The mixture was then filtered, the filter cake was washed with water, and the crude product was purified by silica gel column chromatography to obtain 154 mg of a white solid.

[0117] Yield 79%. 1H NMR (600 MHz, DMSO-d6): δ 10.58 (s, 1H), 10.56 (s, 1H), 8.82 (s, 1H), 8.41 (d, J = 1.8 Hz, 1H), 8.18-8.12 (m, 3H), 7.93 (d, J = 7.8Hz, 2H), 6.92 (d, J = 9.0 Hz, 1H), 6.87 (d, J = 9.0 Hz, 1H), 6.58 (d, J = 2.4Hz, 1H), 6.51 (dd, J = 9.0, 2.4 Hz, 1H), 3.85 (s, 2H), 2.99 (s, 3H), 2.02 (s,3H). 13 C NMR (151 MHz, DMSO-d6): δ 166.64, 164.33, 160.20, 146.56, 142.87,139.61, 138.17, 132.96, 131.51 (q, J C-F = 31.9 Hz), 130.50, 130.21, 128.59(2C), 125.47 (q, J C-F = 3.3 Hz, 2C), 123.93 (q, J C-F = 272.7 Hz), 122.25,121.21, 114.29, 110.60, 109.70, 53.68, 16.57. (One carbon signal wasoverlapped with the peak of DMSO-d6). ESI-HRMS m / z: calcd for C 23 H 21 F3N4O4 [M+H] + 475.1593; found 475.1568. HPLC purity 97.50 %.

[0118] Example 2: Synthesis of N-[6-(4-((4-hydroxyamino-4-oxobutyl)(methyl)amino)-2-methylphenoxy)pyridin-3-yl]-4-(trifluoromethyl)benzamide (Compound 2)

[0119]

[0120] Compound 2 was prepared according to the synthesis in Example 1, except that ethyl bromobutyrate in step (4) was replaced with methyl 4-bromobutyrate, and it underwent deBoc and nucleophilic substitution with intermediate 20, followed by condensation to amide and hydroxylamine hydrolysis according to steps (5) and (6). The prepared compound 2 was a pale yellow solid.

[0121] Yield 43%. 1 H NMR (600 MHz, DMSO-d6): δ 10.56 (s, 1H), 10.40 (s, 1H), 8.71 (s, 1H), 8.43 (d, J = 3.0 Hz, 1H), 8.18-8.11 (m, 3H), 7.92 (d, J = 7.8Hz, 2H), 6.90 (d, J = 9.0 Hz, 1H), 6.86 (d, J = 9.0 Hz, 1H), 6.62 (d, J = 2.4Hz, 1H), 6.56 (dd, J = 8.4, 2.4 Hz, 1H), 3.27 (t, J = 7.2 Hz, 2H), 2.86 (s,3H), 2.05-1.99 (m, 5H), 1.77–1.70 (m, 2H). 13 C NMR (151 MHz, DMSO-d6): δ168.91, 164.33, 160.26, 146.61, 142.44, 139.61, 138.19, 132.91, 131.51 (q,J C-F = 31.9 Hz), 130.49, 130.36, 128.59 (2C), 125.47 (q, J C-F = 3.2 Hz, 2C), 123.93 (q, J C-F = 272.7 Hz), 122.36, 114.29, 110.62, 109.64, 51.72, 38.21,29.53, 22.06, 16.57. ESI-HRMS m / z: calcd for C 25 H 25 F3N4O4 [M+H] + 503.1906; found503.1901. HPLC purity 98.89 %.

[0122] Example 3: Synthesis of N-[6-(4-((8-hydroxyamino-8-oxooctyl)(methyl)amino)-2-methylphenoxy)pyridin-3-yl]-4-(trifluoromethyl)benzamide (compound 3)

[0123]

[0124] Compound 3 was prepared according to the synthesis in Example 1, except that ethyl bromoacetate in step (4) was replaced with ethyl 8-bromooctanoate, and it underwent de-Boc and nucleophilic substitution with intermediate 20, followed by condensation into an amide and hydroxylamine hydrolysis according to steps (5) and (6). The prepared compound 3 was a white solid.

[0125] Yield 54%. 1 H NMR (600 MHz, DMSO-d6): δ 10.57 (s, 1H), 10.35 (s, 1H), 8.69 (s, 1H), 8.44 (d, J = 3.0 Hz, 1H), 8.18-8.13 (m, 3H), 7.91 (d, J = 8.4Hz, 2H), 6.90 (d, J = 9.0 Hz, 1H), 6.85 (d, J = 8.4 Hz, 1H), 6.58 (d, J = 3.0Hz, 1H), 6.53 (dd, J = 8.4, 3.0 Hz, 1H), 3.26 (t, J = 7.2 Hz, 2H), 2.85 (s,3H), 2.02 (s, 3H), 1.94 (t, J = 7.2 Hz, 2H), 1.55-1.42 (m, 4H), 1.31-1.22 (m, 6H). 13 C NMR (151 MHz, DMSO-d6): δ 169.20, 164.35, 160.30, 146.70, 142.36,139.60, 138.20, 132.89, 131.55 (q, J C-F = 31.9 Hz), 130.54, 130.38, 128.61(2C), 125.47 (q, J C-F = 3.5 Hz, 2C), 123.92 (q, J C-F= 272.7 Hz), 122.40,114.19, 110.56, 109.66, 52.19, 38.24, 32.28, 28.72, 28.68, 26.51, 26.04,25.13, 16.58. ESI-HRMS m / z: calcd for C 29 H 33 F3N4O4 [M+H] + 559.2532; found559.2527. HPLC purity 98.06 %.

[0126] Example 4: Synthesis of N-hydroxy-4-[[methyl[3-methyl-4-[(5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy]phenyl]amino]methyl]benzamide (compound 4)

[0127]

[0128] Compound 4 was prepared according to the synthesis in Example 1, except that ethyl bromoacetate in step (4) was replaced with methyl 4-(chloromethyl)benzoate, and it underwent deBoc and nucleophilic substitution with intermediate 20, followed by condensation to amide and hydroxylamine hydrolysis according to steps (5) and (6). The prepared compound 4 was a white solid.

[0129] Yield 39%. 1 H NMR (600 MHz, DMSO-d6): δ 11.16 (s, 1H), 10.57 (s, 1H), 8.99 (brs, 1H), 8.42 (d, J = 2.4 Hz, 1H), 8.19-8.11 (m, 3H), 7.92 (d, J =8.4Hz, 2H), 7.71 (d, J = 7.8 Hz, 2H), 7.31 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 8.4Hz, 1H), 6.85 (d, J = 9.0 Hz, 1H), 6.66 (s, 1H), 6.56 (d, J = 7.8 Hz, 1H), 4.59 (s, 2H), 3.02 (s, 3H), 2.01 (s, 3H). 13 C NMR (151 MHz, DMSO-d6): δ164.32, 164.17, 160.13, 146.49, 142.81, 139.56 (2C), 138.17, 132.92, 131.50(q, JC-F = 32.3 Hz), 131.39, 130.54, 130.42, 128.59 (2C), 127.11, 126.78,125.46 (q, J C-F = 3.5 Hz, 2C), 123.90 (q, J C-F = 272.7 Hz), 122.39, 114.36,110.75, 109.74, 55.62, 39.01, 16.55. ESI-HRMS m / z: calcd for C 29 H 25 F3N4O4 [M+H] + 551.1906; found 551.1901. HPLC purity 95.31 %.

[0130] Example 5: Synthesis of N-hydroxy-5-[[methyl[3-methyl-4-[(5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy]phenyl]amino]methyl]thiophene-2-carboxamide (compound 5)

[0131]

[0132] Compound 5 was prepared according to the synthesis in Example 1, except that ethyl bromoacetate in step (4) was replaced with methyl 5-(bromomethyl)thiophene-2-carboxylic acid, and it underwent deBoc and nucleophilic substitution with intermediate 20, followed by condensation to amide and hydroxylamine hydrolysis in steps (5) and (6) respectively. The prepared compound 4 was a white solid.

[0133] Yield 77%. 1 H NMR (600 MHz, DMSO-d6): δ 11.13 (s, 1H), 10.57 (s, 1H), 9.07 (s, 1H), 8.43 (d, J = 3.0 Hz, 1H), 8.19-8.11 (m, 3H), 7.92 (d, J = 8.4Hz, 2H), 7.46 (s, 1H), 7.01 (d, J = 3.6 Hz, 1H), 6.92 (d, J = 9.0 Hz, 1H), 6.88 (d, J = 9.0 Hz, 1H), 6.74 (d, J = 2.4 Hz, 1H), 6.67 (dd, J = 9.0, 3.0Hz, 1H), 4.71 (s, 2H), 2.95 (s, 3H), 2.03 (s, 3H). 13C NMR (151 MHz, DMSO-d6): δ 164.35, 160.10, 159.56, 146.71, 145.99, 143.33, 139.61, 138.19, 135.70,132.95, 131.51 (q, J C-F = 32.0 Hz), 130.58, 130.45, 128.60 (2C), 127.26,126.04, 125.48 (q, J C-F = 3.2 Hz), 123.94 (q, J C-F = 272.7 Hz, 2C), 122.36,115.23, 111.56, 109.78, 51.26, 38.45, 16.54. ESI-HRMS m / z: calcd forC 27 H 23 F3N4O4S [M+H] + 557.1470; found 557.1465. HPLC purity 95.64 %.

[0134] Example 6: Synthesis of N-hydroxy-2-[4-(N-methyl-N-(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)glycyl)piperazin-1-yl]pyrimidine-5-carboxamide (Compound 6)

[0135] (1) Synthesis of 4-[N-methyl-N-[3-methyl-4-[(5-(4-trifluoromethylbenzoylamino)pyridin-2-yl)oxy]phenyl]glycyl]piperazine-1-carboxylic acid tert-butyl ester (intermediate 24a)

[0136]

[0137] Add 23a (450 mg, 0.92 mmol, 1.0 eq), N-Boc-piperazine (343.9 mg, 1.85 mmol, 2.0 eq), TBD (128.5 mg, 0.92 mmol, 1.0 eq), and THF (9 mL) sequentially to a round-bottom flask. Under nitrogen protection, heat to reflux at 75 °C. After TLC showed complete reaction, remove THF by rotary evaporation, extract with EA, and wash successively with saturated NaHCO3 solution, water, and saturated NaCl solution. Combine the organic phases, dry over anhydrous Na2SO4, concentrate under reduced pressure, and purify the crude product by silica gel column chromatography to obtain 247.1 mg of a pale yellow solid.

[0138] Yield 72%.1 H NMR (600 MHz, DMSO-d6): δ 10.56 (s, 1H), 8.42 (d, J =2.4 Hz, 1H), 8.18-8.12 (m, 3H), 7.92 (d, J = 7.8 Hz, 2H), 6.91 (d, J = 9.0Hz, 1H), 6.83 (d, J = 9.0 Hz, 1H), 6.56 (d, J = 3.0 Hz, 1H), 6.48 (dd, J =9.0, 3.0 Hz, 1H), 4.26 (s, 2H), 3.50-3.45 (m, 2H), 3.44-3.36 (m, 4H), 3.32-3.28 (m, 2H), 2.94 (s, 3H), 2.01 (s, 3H), 1.41 (s, 9H). ESI-MS m / z: 629 [M+H] + .

[0139] (2) Synthesis of methyl 2-(4-{2-[methyl(3-methyl-4-{[5-({[4-(trifluoromethyl)phenyl]carbonyl}amino)pyridin-2-yl]oxy}phenyl)amino]acetyl}piperazin-1-yl)pyrimidine-5-carboxylate (intermediate 25a)

[0140]

[0141] The preparation of intermediate 25a was carried out in accordance with Example 1, except that intermediate 21 in step (4) was replaced with intermediate 24a and ethyl bromoacetate was replaced with methyl 2-chloropyrimidine-5-carboxylic acid; 116.2 mg of pale yellow solid was obtained by the same method.

[0142] Yield 89% in two steps. 1H NMR (600 MHz, DMSO-d6): δ 10.56 (s, 1H), 8.83 (s, 2H), 8.42 (d, J = 3.0 Hz, 1H), 8.17-8.12 (m, 3H), 7.92 (d, J = 8.4Hz, 2H), 6.91 (d, J = 9.0 Hz, 1H), 6.84 (d, J = 12.6 Hz, 1H), 6.58 (d, J =3.0 Hz, 1H), 6.50 (dd, J = 9.0, 3.0 Hz, 1H), 4.32 (s, 2H), 3.96 (t, J = 4.8Hz, 2H), 3.87 (t, J = 5.4 Hz, 2H), 3.81 (s, 3H), 3.63 (t, J = 5.4 Hz, 2H), 3.57 (t, J = 5.4 Hz, 2H), 2.96 (s, 3H), 2.02 (s, 3H). ESI-MS m / z: 665 [M+H] + .

[0143] (3) Synthesis of N-hydroxy-2-[4-(N-methyl-N-(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)glycyl)piperazin-1-yl]pyrimidine-5-carboxamide (compound 6)

[0144]

[0145] Compound 6 was prepared according to Example 1, except that intermediate 23a in step (6) was replaced with intermediate 25a; 46.8 mg of a pale yellow solid was obtained by the same method.

[0146] Yield 43%. 1H NMR (600 MHz, DMSO-d6): δ 11.11 (brs, 1H), 10.57 (s,1H), 9.04 (brs, 1H), 8.71 (s, 2H), 8.42 (d, J = 2.4 Hz, 1H), 8.18-8.12 (m,3H), 7.92 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 9.0 Hz, 1H), 6.84 (d, J = 9.0 Hz,1H), 6.58 (d, J = 3.0 Hz, 1H), 6.50 (dd, J = 9.0, 3.0 Hz, 1H), 4.32 (s, 2H),3.91 (t, J = 5.4 Hz, 2H), 3.82 (t, J = 5.4 Hz, 2H), 3.61 (t, J = 5.4 Hz, 2H),3.55 (t, J = 5.4 Hz, 2H), 2.96 (s, 3H), 2.02 (s, 3H). 13 C NMR (151 MHz, DMSO-d6): δ 167.89, 164.34, 161.81, 161.39, 160.26, 157.14, 147.02, 142.57,139.62, 138.19, 132.95, 131.50 (q, J C-F = 31.7 Hz), 130.47, 130.07, 128.60(2C), 125.47 (q, J C-F = 3.5 Hz, 2C), 123.91 (q, J C-F = 272.7 Hz), 122.15,114.94, 114.16, 110.53, 109.67, 53.08, 43.72, 43.49, 43.35, 40.89, 39.32,16.58. ESI-HRMS m / z: calcd for C 32 H 31 F3N8O5 [M+H] + 665.2448. HPLC purity 97.94%。

[0147] Example 7: Synthesis of N-hydroxy-2-[6-(N-methyl-N-(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)glycyl)-2,6-diazaspiro[3.3]heptane-2-yl]pyrimidine-5-carboxamide (compound 7)

[0148]

[0149] Compound 7 was prepared according to the synthesis in Example 6, except that N-Boc-piperazine in step (1) was replaced with tert-butyl 2,6-diazaspiro[3.3]heptane-2-carboxylic acid, which was then reacted with intermediate 23a under TBD conditions to form an amide, followed by aromatic nucleophilic substitution and hydroxylamine hydrolysis according to steps (2) and (3). The prepared compound 7 was a pale yellow solid.

[0150] Yield 57%. 1 H NMR (600 MHz, DMSO-d6): δ 11.09 (s, 1H), 10.57 (s, 1H),9.03 (brs, 1H), 8.65 (s, 2H), 8.42 (d, J = 2.4 Hz, 1H), 8.19-8.11 (m, 3H),7.92 (d, J = 8.4 Hz, 2H), 6.92 (d, J = 8.4 Hz, 1H), 6.86 (d, J = 9.0 Hz, 1H), 6.58 (d, J = 3.0 Hz, 1H), 6.50 (dd, J = 9.0, 3.0 Hz, 1H), 4.41 (s, 2H), 4.26(s, 4H), 4.11 (s, 2H), 3.98 (s, 2H), 2.94 (s, 3H), 2.03 (s, 3H). 13 C NMR (151MHz, DMSO-d6): δ 168.88, 163.73, 161.54, 159.60, 156.41, 146.17, 142.18,139.01, 137.56, 132.35, 130.89 (q, J C-F = 31.7 Hz), 129.90, 129.58, 128.00(2C), 124.85 (q, J C-F = 3.6 Hz, 2C), 123.32 (q, J C-F= 272.6 Hz), 121.62,113.62, 109.96, 109.08, 59.22, 57.54, 52.17, 38.70, 32.69, 30.94, 28.82,15.97. ESI-HRMS m / z: calcd for C 33 H 31 F3N8O5 [M+H] + 677.2448; found 677.2442. HPLC purity 95.56 %.

[0151] Example 8: Synthesis of N-hydroxy-2-[6-(N-methyl-N-(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)glycyl)-2,6-diazaspiro[3,4]octane-2-yl]pyrimidine-5-carboxamide (compound 8)

[0152]

[0153] Compound 8 was prepared according to the synthesis in Example 6, except that N-Boc-piperazine in step (1) was replaced with tert-butyl 2,6-diazaspiro[3.4]octane-2-carboxylic acid, which was then reacted with intermediate 23a under TBD conditions to form an amide, followed by aromatic nucleophilic substitution and hydroxylamine hydrolysis according to steps (2) and (3). The prepared compound 8 was a pale yellow solid.

[0154] Yield 41%. 1H NMR (600 MHz, DMSO-d6): δ 11.10 (brs, 1H), 10.60 (s,1H), 9.12 (brs, 1H), 8.66 (d, J = 9.6 Hz, 1H), 8.42 (s, 1H), 8.20-8.10 (m,3H), 7.92 (d, J = 7.8 Hz, 2H), 6.91 (d, J = 8.4 Hz, 1H), 6.84 (dd, J =9.0,2.4 Hz, 1H), 6.59-6.55 (m, 1H), 6.50 (dd, J = 9.0, 3.6 Hz, 1H), 4.19-4.10 (m,3H), 4.09-4.01 (m, 3H), 3.79-3.74 (m, 1H), 3.63-3.53 (m, 2H), 3.43-3.38 (m,1H), 2.96 (s, 3H), 2.22 (t, J = 6.6 Hz, 1H), 2.08 (t, J = 6.6 Hz, 1H), 2.02(s, 3H). 13 C NMR (151 MHz, DMSO-d6): δ 167.68, 164.33, 162.35, 161.82, 160.25,156.95, 146.99, 142.53, 139.63, 138.18, 132.95, 131.48 (q, J C-F = 31.9 Hz),130.46, 130.04, 128.60 (2C), 125.46 (q, J C-F = 3.6 Hz, 2C), 123.91 (q, J C-F =272.7 Hz), 122.13, 121.21, 115.37, 114.11, 110.50, 109.64, 58.89, 58.69,44.30, 40.80, 39.30, 38.70, 36.05, 33.77, 16.58. ESI-HRMS m / z: calcd forC 34 H 33 F3N8O5 [M+H] + 691.2604; found 691.2599. HPLC purity 95.10 %。

[0155] Example 9: Synthesis of N-hydroxy-2-[7-(N-methyl-N-(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)glycyl)-2,7-diazaspiro[4,4]nonane-2-yl]pyrimidine-5-carboxamide (compound 9)

[0156]

[0157] Compound 9 was prepared according to the synthesis in Example 6, except that N-Boc-piperazine in step (1) was replaced with tert-butyl 2,7-diazaspiro[4.4]nonane-2-carboxylic acid, which was then reacted with intermediate 23a under TBD conditions to form an amide, followed by aromatic nucleophilic substitution and hydroxylamine hydrolysis according to steps (2) and (3). The prepared compound 9 was a pale yellow solid.

[0158] Yield 43%. 1 H NMR (600 MHz, DMSO-d6): δ 11.07 (s, 1H), 10.57 (s, 1H), 8.98 (s, 1H), 8.74-8.58 (m, 2H), 8.42 (s, 1H), 8.21-8.06 (m, 3H), 7.92 (d, J= 8.4 Hz, 2H), 6.91 (d, J = 8.4 Hz, 1H), 6.83 (dd, J = 9.0, 5.4 Hz, 1H), 6.56(d, J = 10.8 Hz, 1H), 6.53-6.45 (m, 1H), 4.24-4.07 (m, 2H), 3.74-3.41 (m,8H), 2.96 (d, J = 7.2 Hz, 3H), 2.08-1.94 (m, 6H), 1.93-1.81 (m, 1H). 13 C NMR(151 MHz, DMSO-d6): δ 167.76, 164.33, 162.17, 160.27, 160.17, 157.01, 156.97,147.00, 142.51, 139.64, 138.18, 132.96, 131.50 (q,J C-F = 32.2 Hz), 130.45,130.05, 128.60 (2C), 125.47 (q, J C-F = 3.8 Hz, 2C), 123.89 (q, J C-F= 272.7Hz), 122.13, 114.08, 114.06, 110.48, 109.65, 55.33, 55.27, 48.70, 46.36,45.86, 34.73, 33.85, 33.64, 32.83, 16.58. ESI-HRMS m / z: calcd for C 35 H 35 F3N8O5[M+H] + 705.2761; found 705.2755. HPLC purity 97.32 %.

[0159] Example 10: Synthesis of N-hydroxy-2-[4-[(methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidin-1-yl]pyrimidine-5-carboxamide (compound 10)

[0160] (1) Synthesis of methyl 2-{4-[(methyl{3-methyl-4-[(5-nitropyridin-2-yl)oxy]phenyl}amino)methyl]piperidin-1-yl}pyrimidine-5-carboxylate (intermediate 26)

[0161]

[0162] The preparation of intermediate 26 was carried out in accordance with Example 1, except that the ethyl bromoacetate in step (4) was replaced with methyl 2-(4-(((methanesulfonyl)oxy)methyl)piperidin-1-yl)pyrimidine-5-carboxylate; 202.3 mg of pale yellow solid was obtained by the same method.

[0163] Yield 44% for two steps. 1 H NMR (600 MHz, CDCl3): δ 9.00 (d, J = 2.4Hz, 1H), 8.84 (s, 2H), 8.54 (dd, J = 9.0, 3.0 Hz, 1H), 7.63 (d, J = 9.0 Hz,2H), 7.22 (s, 1H), 7.14 (d, J =8.4 Hz, 1H), 4.98-4.86 (m, 2H), 3.88 (s, 3H), 3.20 (d, J = 7.2 Hz, 2H), 3.03-2.85 (m, 5H), 2.28- 2.15 (m, 4H), 1.74-1.43(m, 2H), 1.33-1.19 (m, 2H). ESI-MS m / z: 493 [M +H] +.

[0164] (2) Synthesis of methyl 2-[4-[(methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidin-1-yl]pyrimidine-5-carboxylic acid (intermediate 27)

[0165]

[0166] For the preparation of intermediate 27, refer to Example 1, replace intermediate 22a in step (5) with intermediate 26; 147.2 mg of white solid was obtained by the same method.

[0167] Yield 58%. 1 H NMR (600 MHz, DMSO-d6): δ 10.58 (s, 1H), 8.76 (dd, J =9.0, 3.0 Hz, 1H), 8.42 (d, J = 3.0 Hz, 1H), 8.21-8.08 (m, 3H), 7.92 (d, J =8.4 Hz, 2H), 6.90 (d, J = 9.0 Hz, 1H), 6.86 (d, J = 9.0 Hz, 1H), 6.59 (d, J =2.4 Hz, 1H), 6.54 (dd, J = 9.0, 2.4 Hz, 1H), 4.79 (dt, J = 13.2, 3.0 Hz, 2H),3.78 (s, 3H), 3.19 (d, J = 7.2 Hz, 2H), 3.01-2.87 (m, 5H), 2.10-1.95 (m, 4H), 1.81-1.69 (m, 2H), 1.22 (qd, J = 12.6, 4.2 Hz, 2H). ESI-MS m / z: 635 [M +H] + .

[0168] (3) Synthesis of N-hydroxy-2-[4-[(methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidin-1-yl]pyrimidine-5-carboxamide (compound 10)

[0169]

[0170] Compound 10 was prepared according to Example 1, except that intermediate 23a in step (6) was replaced with intermediate 25a; 70.1 mg of white solid was obtained by the same method.

[0171] Yield 50%.1 H NMR (600 MHz, DMSO-d6): δ 11.03 (brs, 1H), 10.56 (s,1H), 8.99 (s, 1H), 8.66 (s, 2H), 8.43 (d, J = 2.4 Hz, 1H), 8.18-8.11 (m, 3H),7.92 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 8.4 Hz, 1H), 6.86 (d, J = 9.0 Hz, 1H),6.59 (d, J = 2.4 Hz, 1H), 6.55 (dd, J = 9.0, 3.0 Hz, 1H), 4.78-4.72 (m, 2H),3.19 (d, J = 7.2 Hz, 2H), 2.97-2.84 (m, 5H), 2.10-2.00 (m, 4H), 1.77-1.70 (m,2H), 1.20 (qd, J = 12.6, 4.2 Hz, 2H). 13 C NMR (151 MHz, DMSO-d6): δ 164.32,162.02, 161.30, 160.28, 157.11 (2C), 146.76, 142.24, 139.57, 138.18, 132.89,131.50 (q, J C-F = 31.7 Hz), 130.49, 130.34, 128.59 (2C), 125.47 (q, J C-F = 3.0Hz, 2C), 123.92 (q, J C-F = 273.3 Hz), 122.35, 114.07, 113.78, 110.18, 109.66,57.85, 43.51 (2C), 34.90, 29.52 (2C), 16.59. (One carbon signal wasoverlapped with the peak of DMSO-d6). ESI-HRMS m / z: calcd for C 32 H 32 F3N7O4 [M+H] + 636.2546. HPLC purity 96.17 %。

[0172] Example 11: Synthesis of N-hydroxy-2-[4-[methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-yl]pyrimidine-5-carboxamide (compound 11)

[0173] (1) Synthesis of 4-[methyl[3-methyl-4-[(5-nitropyridin-2-yl)oxy]phenyl]amino]piperidine-1-carboxylic acid tert-butyl ester (intermediate 28)

[0174]

[0175] Intermediate 21 (1.22 g, 3.18 mmol, 1.0 eq) and DCM (16 mL) were added to a round-bottom flask. TFA (4 mL) was added dropwise under ice bath. After the addition was complete, the mixture was moved to room temperature. After the TLC showed that the reaction was complete, saturated NaHCO3 solution was added to quench the reaction. The mixture was extracted with EA and washed successively with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, and concentrated under reduced pressure to give a pale red solid, which was used directly in the next step without purification.

[0176] The above product (700.33 mg, 2.70 mmol, 1.0 eq) and DCM (10 mL) were added to a round-bottom flask. N-tert-butyloxycarbonyl-4-piperidinone (1.07 g, 5.40 mmol, 2.0 eq), HOAc (154 μL, 2.70 mmol, 1.0 eq), and NaBH(OAc)3 (1.72 g, 8.10 mmol, 3.0 eq) were added under ice bath conditions, and the mixture was then allowed to react at room temperature. After TLC showed complete reaction, the pH was adjusted to 7 with saturated NaHCO3 solution, and the mixture was extracted with DCM. The extract was washed successively with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography to obtain 776.6 mg of a pale yellow solid.

[0177] Yield 65% for two steps. 1H NMR (600 MHz, CDCl3): δ 9.05 (d, J = 2.4Hz, 1H), 8.44 (dd, J = 9.0, 3.0 Hz, 1H), 6.96 (d, J = 9.0 Hz, 1H), 6.93 (d, J= 8.4 Hz, 1H), 6.71-6.64 (m, 2H), 4.36-4.15 (m, 2H), 3.74-3.64 (m, 1H), 2.88-2.66 (m, 5H), 2.11 (s, 3H), 1.79-1.61 (m, 4H), 1.48 (s, 9H). ESI-MS m / z: 444[M +H] + .

[0178] (2) Synthesis of 4-[methyl[3-methyl-4-[(5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy]phenyl]amino]piperidine-1-carboxylic acid tert-butyl ester (intermediate 29)]

[0179]

[0180] The preparation of intermediate 29 was carried out in accordance with Example 1, except that intermediate 22a in step (5) was replaced with intermediate 28; 508.4 mg of light red solid was obtained by the same method.

[0181] Yield 64%. 1 H NMR (600 MHz, CDCl3): δ 10.56 (s, 1H), 8.43 (d, J = 2.4Hz, 1H), 8.18-8.13 (m, 3H), 7.92 (d, J = 7.8 Hz, 2H), 6.91 (d, J = 9.0 Hz, 1H), 6.87 (d, J = 8.4 Hz, 1H), 6.74 (d, J = 3.0 Hz, 1H), 6.69 (dd, J = 9.0 ,3.0 Hz, 1H), 4.10-3.99 (m, 2H), 3.78 (tt, J = 11.4, 3.6 Hz, 1H), 2.95-2.75(m, 2H), 2.68(s, 3H), 2.04 (s, 3H), 1.65-1.59 (m, 2H), 1.54 (qd, J = 12.0,4.8 Hz, 2H), 1.41 (s, 9H). ESI-MS m / z: 586 [M+H] + .

[0182] (3) Synthesis of methyl 2-[4-[methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-yl]pyrimidine-5-carboxylic acid (intermediate 30)

[0183]

[0184] The preparation of intermediate 30 was carried out in accordance with Example 1, except that the ethyl bromoacetate in step (4) was replaced with methyl 2-chloropyrimidine-5-carboxylic acid; 45.6 mg of white solid was obtained by the same method.

[0185] Yield 62% for two steps. 1 H NMR (600 MHz, DMSO-d6): δ 10.57 (s, 1H), 8.80 (s, 2H), 8.43 (d, J = 3.0 Hz, 1H), 8.18-8.13 (m, 3H), 7.93 (d, J = 8.4Hz, 2H), 6.93 (d, J = 8.4 Hz, 1H), 6.89 (d, J = 8.4 Hz, 1H), 6.79 (d, J = 3.0Hz, 1H), 6.73 (dd, J = 9.0, 3.0 Hz, 1H), 4.94-4.88 (m, 2H), 4.01 (tt, J =11.4, 4.2 Hz, 1H), 3.80 (s, 3H), 3.12 (td, J = 13.2, 2.4 Hz, 2H), 2.67 (s,3H), 2.05 (s, 3H), 1.79-1.73 (m, 2H), 1.65 (qd, J = 12.0, 4.2 Hz, 2H). ESI-MSm / z: 622 [M+H] + .

[0186] (4) Synthesis of N-hydroxy-2-[4-[methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-yl]pyrimidine-5-carboxamide (compound 11)

[0187]

[0188] Compound 11 was prepared according to Example 1, except that intermediate 23a in step (6) was replaced with intermediate 30; 35.7 mg of white solid was obtained by the same method.

[0189] Yield 83%. 1H NMR (600 MHz, DMSO-d6): δ 10.58 (brs, 1H), 9.01 (s,1H), 8.68 (brs, 2H), 8.43 (d, J = 2.7 Hz, 1H), 8.19-8.11 (m, 3H), 7.92 (d, J= 7.8 Hz, 2H), 6.92 (d, J = 8.4 Hz, 1H), 6.89 (d, J = 8.4 Hz, 1H), 6.79 (d, J= 2.4 Hz, 1H), 6.73 (dd, J = 9.0, 2.4 Hz, 1H), 4.87 (d, J = 13.2 Hz, 2H),4.03-3.91 (m, 1H), 3.06 (t, J = 12.6 Hz, 2H), 2.67 (s, 3H), 2.05 (s, 3H), 1.74 (d, J = 12.0 Hz, 2H), 1.68-1.57 (m, 2H). 13 C NMR (151 MHz, DMSO-d6): δ164.35, 161.21 (2C), 160.19, 159.54, 157.08, 147.24, 143.00, 139.60, 138.19,132.93, 131.52 (q, J = 32.2 Hz), 130.55, 130.38, 128.60 (2C), 125.49 (q, J =3.8 Hz, 2C), 123.92 (q, J C-F = 272.6 Hz), 122.32, 115.88, 114.02, 112.17,109.72, 56.22, 43.16 (2C), 31.38, 28.43 (2C), 16.56. ESI-HRMS m / z: calcd forC 31 H 30 F3N7O4 [M+H + 622.2390. HPLC purity 95.03%.

[0190] Example 12: Synthesis of N-hydroxy-4-[4-[(methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidin-1-carbonyl]benzamide (compound 12)

[0191] (1) Synthesis of 4-[(methyl(3-methyl-4-((5-nitro-2-pyridyl)oxy)phenyl)amino)methyl]piperidine-1-carboxylic acid tert-butyl ester (intermediate 31)

[0192]

[0193] The preparation of intermediate 31 was carried out in accordance with Example 1, except that the ethyl bromoacetate in step (4) was replaced with tert-butyl 4-[[(methylsulfonyl)oxy]methyl]piperidine-1-carboxylic acid; 1.2 g of a pale red solid was obtained by the same method.

[0194] Yield 85% in two steps. 1 H NMR (600 MHz, CDCl3): δ 9.05 (d, J = 2.4Hz, 1H), 8.43 (dd, J = 9.0, 3.0 Hz, 1H), 6.96 (d, J = 9.0 Hz, 1H), 6.91 (d, J= 9.6 Hz, 1H), 6.53 (s, 2H), 4.33-4.09 (m, 2H), 3.17 (d, J = 6.6 Hz, 2H), 2.97 (s, 3H), 2.76-2.59 (m, 2H), 2.10 (s, 3H), 1.92-1.85 (m, 1H), 1.70 (d, J= 12.6 Hz, 2H), 1.46 (s, 9H), 1.21-1.10 (m, 2H). ESI-MS m / z: 458 [M+H] + .

[0195] (2) Synthesis of 4-[(methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidine-1-carboxylic acid tert-butyl ester (intermediate 32)

[0196]

[0197] The preparation of intermediate 32 was carried out in accordance with Example 1, except that intermediate 22a in step (5) was replaced with intermediate 31; 904 mg of pale yellow solid was obtained by the same method.

[0198] Yield 58%. 1H NMR (600 MHz, DMSO-d6): δ 10.55 (s, 1H), 8.42 (d, J =3.0 Hz, 1H), 8.17-8.12 (m, 3H), 7.93 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 8.4Hz, 1H), 6.85 (d, J = 8.4 Hz, 1H), 6.57 (d, J = 3.0 Hz, 1H), 6.53 (dd, J =9.0, 3.0 Hz, 1H), 4.01-3.90 (m, 2H), 3.17 (d, J = 7.2 Hz, 2H), 2.91 (s, 3H),2.76-2.58 (m, 2H), 2.03 (s, 3H), 1.91-1.82 (m, 1H), 1.66-1.59 (m, 2H), 1.39(s, 9H), 1.07 (qd, J = 12.6, 4.2 Hz, 2H). ESI-MS m / z: 600 [M+H] + .

[0199] (3) Synthesis of methyl 4-[4-[(methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidin-1-carbonyl]benzoate (intermediate 33a)

[0200]

[0201] Intermediate 32 (900 mg, 1.50 mmol, 1.0 eq) and DCM (16 mL) were added to a round-bottom flask. TFA (4 mL) was added dropwise under ice bath conditions. After the addition was complete, the mixture was moved to room temperature. Once the reaction was complete as indicated by TLC, saturated NaHCO3 solution was added to quench the reaction. The mixture was extracted with EA and washed successively with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, and concentrated under reduced pressure to obtain a pale red solid, which was used directly in the next step without purification.

[0202] 4-(methoxycarbonyl)benzoic acid (150 mg, 0.30 mmol, 1.0 eq), EDCI (86.5 mg, 0.45 mmol, 1.5 eq), HOBt (61 mg, 0.45 mmol, 1.5 eq), and DCM (3 mL) were added sequentially to a round-bottom flask. The reaction was allowed to proceed for 0.5 h. Then, the product (81.3 mg, 0.45 mmol, 1.5 eq) and TEA (126 μL, 0.90 mmol, 3.0 eq) were added, and the reaction was allowed to proceed at room temperature. After TLC showed complete reaction, the mixture was extracted with EA and washed sequentially with saturated NaHCO3 solution, water, and saturated NaCl solution. The organic phases were combined, dried over anhydrous Na2SO4, concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography to give 156.7 mg of a white solid.

[0203] Yield 79% for two steps. 1 H NMR (600 MHz, DMSO-d6): δ 10.58 (s, 1H), 8.41 (d, J = 2.4 Hz, 1H), 8.17-8.12 (m, 3H), 8.02 (d, J = 8.4 Hz, 2H), 7.93(d, J = 7.8 Hz, 2H), 7.52 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 8.4 Hz, 1H), 6.86(d, J = 9.0 Hz, 1H), 6.58 (d, J = 3.0 Hz, 1H), 6.54 (dd, J = 9.0, 3.0 Hz,1H), 4.51 (d, J = 12.6 Hz, 1H), 3.87 (s, 3H), 3.48 (d, J = 13.8 Hz, 1H), 3.26-3.16 (m, 2H), 3.03 (t, J = 12.6 Hz, 1H), 2.92 (s, 3H), 2.75 (t, J = 12.6Hz, 1H), 2.07-1.95 (m, 4H), 1.76 (d, J = 12.6 Hz, 1H), 1.60 (d, J = 12.6 Hz, 1H), 1.22-1.13 (m, 2H). ESI-MS m / z: 662 [M+H] + .

[0204] (4) Synthesis of N-hydroxy-4-[4-[(methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino)methyl]piperidine-1-carbonyl]benzamide (compound 12)

[0205]

[0206] Compound 12 was prepared according to Example 1, except that intermediate 23a in step (6) was replaced with intermediate 33a; 143 mg of white solid was obtained by the same method.

[0207] Yield 69%. 1 H NMR (600 MHz, DMSO-d6): δ 11.30 (s, 1H), 10.56 (s, 1H), 9.11 (s, 1H), 8.42 (d, J = 1.8 Hz, 1H), 8.19-8.12 (m, 3H), 7.92 (d, J = 8.4Hz, 2H), 7.80 (d, J = 8.4 Hz, 2H), 7.45 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 9.0Hz, 1H), 6.86 (d, J = 8.7 Hz, 1H), 6.59 (d, J = 3.0 Hz, 1H), 6.54 (dd, J =9.0, 3.0 Hz, 1H), 4.51 (d, J = 9.0 Hz, 1H), 3.52 (d, J = 12.0 Hz, 1H), 3.26-3.15 (m, 2H), 3.04-3.01 (m, 1H), 2.92 (s, 3H), 2.80-2.69 (m, 1H), 2.09-1.96(m, 4H), 1.76 (d, J = 10.8 Hz, 1H), 1.60 (d, J = 9.6 Hz, 1H), 1.22-1.11 (m,2H). 13 C NMR (151 MHz, DMSO-d6): δ 168.16, 164.33, 163.62, 160.26, 146.73,142.28, 139.56, 139.07, 138.18, 133.43, 132.90, 131.97 (q, J C-F = 31.9 Hz),130.49, 130.36, 128.59 (2C), 127.06, 126.64, 125.47 (q, J C-F= 3.8 Hz, 2C), 123.89 (q, J C-F (One carbon signal was overlapped with the peak of DMSO-d6). ESI-HRMS m / z: calcd for C 35 H 34 F3N5O5 [M+H + 662.2590; found 662.2585.

[0208] Example 13: Synthesis of N-hydroxy-6-(4-((methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino)methyl)piperidine-1-carbonyl)nicotinamide (compound 13)

[0209]

[0210] Compound 13 was prepared according to the synthesis in Example 12, except that 4-(methoxycarbonyl)benzoic acid in step (3) was replaced with 5-(methoxycarbonyl)pyridine-2-carboxylic acid, and condensed with intermediate 32 to form an amide, followed by hydroxylamine hydrolysis according to step (4). The prepared compound 13 was a white solid.

[0211] Yield 56%. 1H NMR (600 MHz, DMSO-d6): δ 11.46 (s, 1H), 10.56 (s, 1H),9.29 (s, 1H), 8.89 (s, 1H), 8.42 (d, J = 3.0 Hz, 1H), 8.20 (d, J = 7.8 Hz,1H), 8.18-8.12 (m, 3H), 7.93 (d, J = 7.8 Hz, 2H), 7.62 (d, J = 7.8 Hz, 1H),6.91 (d, J = 9.0 Hz, 1H), 6.86 (d, J = 9.0 Hz, 1H), 6.59 (d, J = 2.4 Hz, 1H),6.54 (dd, J = 9.0, 3.0 Hz, 1H), 4.52 (d, J = 12.6 Hz, 1H), 3.58 (d, J = 12.6Hz, 1H), 3.26-3.16 (m, 2H), 3.06-2.97 (m, 1H), 2.92 (s, 3H), 2.80-2.69 (m,1H), 2.09-1.96 (m, 4H), 1.78 (d, J = 13.2 Hz, 1H), 1.60 (d, J = 12.6 Hz, 1H),1.23-1.17 (m, 2H). 13 C NMR (151 MHz, DMSO-d6): δ 165.45, 163.71, 161.42,159.65, 155.92, 146.32, 146.09, 141.64, 138.95, 137.57, 135.32, 132.29,130.89 (q, J C-F = 31.7 Hz), 129.87, 129.74, 128.06, 127.97 (2C), 124.86 (q,J C-F = 4.5 Hz, 2C), 123.35 (q, J C-F = 273.3 Hz), 121.77, 113.15, 109.56,109.06, 57.15, 45.87, 40.82, 34.06, 29.58, 28.81, 15.97. (One carbon signalwas overlapped with the peak of DMSO-d6). ESI-HRMS m / z: calcd for C 34 H33 F3N6O5[M+H] + 663.2543; found 663.2537. HPLC purity 98.59 %.

[0212] Example 14: Synthesis of N-hydroxy-5-(4-((methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino)methyl)piperidine-1-carbonyl)pyridin-2-carboxamide (compound 14)

[0213]

[0214] Compound 14 was prepared according to the synthesis in Example 12, except that 4-(methoxycarbonyl)benzoic acid in step (3) was replaced with 6-(methoxycarbonyl)nicotinic acid, and it was condensed with intermediate 32 to form an amide, followed by hydroxylamine hydrolysis according to step (4). The prepared compound 14 was a white solid.

[0215] Yield 61%. 1 H NMR (600 MHz, DMSO-d6): δ 11.47 (s, 1H), 10.56 (s, 1H), 9.29 (s, 1H), 8.89 (s, 1H), 8.42 (d, J = 1.8 Hz, 1H), 8.20 (dd, J = 7.8, 1.8Hz, 1H), 8.18-8.10 (m, 3H), 7.92 (d, J = 7.8 Hz, 2H), 7.62 (d, J = 8.4 Hz,1H), 6.91 (d, J = 9.0 Hz, 1H), 6.86 (d, J = 8.4 Hz, 1H), 6.59 (d, J = 2.9 Hz,1H), 6.54 (dd, J = 8.4, 2.4 Hz, 1H), 4.53 (d, J = 12.6 Hz, 1H), 3.58 (d, J =13.2 Hz, 1H), 3.27-3.15 (m, 1H), 3.06-2.98 (m, 1H), 2.92 (s, 3H), 2.82-2.73(m, 1H), 2.09-1.97 (m, 4H), 1.78 (d, J = 12.6 Hz, 1H), 1.60 (d, J = 12.6 Hz, 1H). 13C NMR (151 MHz, DMSO-d6): δ 166.53, 164.79, 162.50, 160.72, 156.99,147.40, 147.17, 142.72, 140.02, 138.64, 136.40, 133.36, 131.97 (q,J C-F = 32.2Hz), 130.95, 130.82, 129.14, 129.05 (2C), 125.93 (q, J C-F = 3.6 Hz, 2C), 124.36 (q, J C-F = 272.9 Hz), 122.85, 114.23, 110.63, 110.13, 58.23, 46.95,41.90, 35.14, 30.65, 29.89, 17.05. (One carbon signal was overlapped with the peak of DMSO-d6). m / z: calcd for C 34 H 33 F3N6O5 [M+H] + 663.2543; found663.2537. HPLC purity 98.64%.

[0216] Example 15: Synthesis of N-hydroxy-5-(4-((methyl(3-methyl-4-((5-(4-trifluoromethylbenzamido)pyridin-2-yl)oxy)phenyl)amino)methyl)piperidine-1-carbonyl)thiophene-2-carboxamide (compound 15)

[0217]

[0218] Compound 15 was prepared according to the synthesis in Example 12, except that 4-(methoxycarbonyl)benzoic acid in step (3) was replaced with 5-(methoxycarbonyl)thiophene-2-carboxylic acid, which was then condensed with intermediate 32 to form an amide, and then subjected to hydroxylamine hydrolysis according to step (4). The prepared compound 15 was a pale yellow solid.

[0219] Yield 51%. 1H NMR (600 MHz, DMSO- d6): δ 11.38 (s, 1H), 10.57 (s,1H), 9.25 (s, 1H), 8.43 (d, J = 1.8 Hz, 1H), 8.19-8.11 (m, 3H), 7.92 (d, J =7.8 Hz, 2H), 7.56 (s, 1H), 7.34 (d, J = 3.6 Hz, 1H), 6.91 (d, J = 9.0 Hz,1H), 6.86 (d, J = 9.0 Hz, 1H), 6.60 (d, J = 2.4 Hz, 1H), 6.55 (dd, J = 9.0,3.0 Hz, 1H), 4.58-3.91 (m, 4H), 3.21 (d, J = 6.6 Hz, 2H), 2.92 (s, 3H), 2.12-1.98 (m, 4H), 1.72 (d, J = 11.4 Hz, 2H), 1.22-1.15 (m, 2H). 13 C NMR (151 MHz,DMSO-d6): δ 164.33, 161.54, 160.27, 158.80, 146.73, 142.29, 140.66, 139.57,139.23, 138.18, 132.90, 131.51 (q, J C-F = 32.0 Hz), 130.49, 130.36, 128.85,128.59 (2C), 126.87, 125.47 (q, J C-F = 3.3 Hz, 2C), 123.90 (q, J C-F = 272.6Hz), 122.36, 113.81, 110.21, 109.67, 57.75, 34.69, 29.04, 28.71, 26.56,22.11, 16.59. ESI-HRMS m / z: calcd for C 33 H 32 F3N5O5S [M+H] + 668.2154; found668.2149. HPLC purity 97.02 %。

[0220] Example 16: Synthesis of N-hydroxy-6-[4-[methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-carbonyl]nicotinamide (compound 16)

[0221] (1) Synthesis of methyl 6-[4-[methyl-(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-carbonyl]nicotinic acid (intermediate 34a)

[0222]

[0223] The preparation of intermediate 33a was carried out in accordance with Example 12, except that intermediate 32 in step (3) was replaced with intermediate 29, and 4-(methoxycarbonyl)benzoic acid was replaced with 5-(methoxycarbonyl)pyridine-2-carboxylic acid; 69 mg of a light red solid was obtained by the same method.

[0224] Yield 57% for two steps. 1 H NMR (600 MHz, DMSO-d6): δ 10.56 (s, 1H),9.10-9.08 (m, 1H), 8.44-8.39 (m, 2H), 8.17-8.12 (m, 3H), 7.93 (d, J = 7.8 Hz,2H), 7.75 (d, J = 4.66-4.60 (m,1H), 3.95 (tt, J = 11.4, 4.2 Hz, 1H), 3.91 (s, 3H), 3.63-3.57 (m, 1H), 3.21(td, J = 14.4, 3.0 Hz, 1H), 2.94 (td, J = 12.6, 3.0 Hz, 1H), 2.72 (s, 3H),2.04 (s, 3H), 1.81-1.75 (m, 1H), 1.75-1.63 (m, 2H), 1.61-1.55 (m, 1H); ESI-MSm / z: 649 [M +H] + .

[0225] (2) Synthesis of N-hydroxy-6-[4-[methyl(3-methyl-4-((5-(4-(trifluoromethyl)benzamido)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-carbonyl]nicotinamide (compound 16)

[0226]

[0227] Compound 16 was prepared according to Example 1, except that intermediate 23a in step (6) was replaced with intermediate 34a; 25 mg of white solid was obtained by the same method.

[0228] Yield 39%. 1 H NMR (600 MHz, DMSO-d6): δ 11.47 (s, 1H), 10.56 (s, 1H), 9.29 (s, 1H), 8.90 (d, J = 2.4 Hz, 1H), 8.42 (d, J = 3.0 Hz, 1H), 8.21 (dd, J= 8.4, 2.4 Hz, 1H), 8.17-8.12 (m, 3H), 7.93 (d, J = 8.4 Hz, 2H), 7.69 (d, J =7.8 Hz, 1H), 6.92 (d, J = 8.4 Hz, 1H), 6.88 (d, J = 9.0 Hz, 1H), 6.77 (d, J =3.0 Hz, 1H), 6.72 (dd, J = 8.4, 3.0 Hz, 1H), 4.68-4.59 (m, 1H), 3.99-3.91 (m,1H), 3.70-3.61 (m, 1H), 3.25-3.15 (m, 1H), 2.97-2.89 (m, 1H), 2.72 (s, 3H), 2.04 (s, 3H), 1.81-1.75 (m, 1H), 1.74-1.64 (m, 2H), 1.63-1.56 (m, 1H). 13 C NMR(151 MHz, DMSO-d6): δ 166.09, 164.33, 162.02, 160.15, 156.39, 147.14, 146.94,143.03, 139.57, 138.17, 135.93, 132.91, 131.50 (q,J C-F = 31.9 Hz), 130.54,130.36, 128.75, 128.58 (2C), 125.47 (q, J C-F= 3.6 Hz, 2C), 123.89 (q, J C-F =271.8 Hz), 122.50, 122.29, 115.88, 112.15, 109.71, 55.82, 46.10, 41.14,31.40, 29.17, 28.45, 16.54. ESI-HRMS m / z: calcd for C 33 H 31 F3N6O5 [M+H] + 649.2386.

[0229] Example 17: Synthesis of N-hydroxy-5-[4-[methyl-[3-methyl-4-((5-(4-trifluoromethylbenzoylamino)pyridin-2-yl)oxy)phenyl)amino]piperidin-1-carbonyl]thiophene-2-carboxamide (compound 17)

[0230]

[0231] Compound 17 was prepared according to the synthesis in Example 16, except that intermediate 32 in step (1) was replaced with intermediate 29, and 4-(methoxycarbonyl)benzoic acid was replaced with 5-(methoxycarbonyl)thiophene-2-carboxylic acid for deBoc removal and condensation to form an amide, followed by hydroxylamine hydrolysis as described in step (2). The prepared compound 17 was a white solid.

[0232] Yield 59%. 1 H NMR (600 MHz, DMSO-d6): δ 11.38 (s, 1H), 10.56 (s, 1H), 9.25 (s, 1H), 8.43 (d, J = 3.0 Hz, 1H), 8.15 (m, 3H), 7.93 (d, J = 8.4 Hz, 2H), 7.57 (d, J = 3.0 Hz, 1H), 7.41 (d, J = 3.6 Hz, 1H), 6.92 (d, J = 8.4 Hz,1H), 6.88 (d, J = 8.4 Hz, 1H), 6.78 (d, J = 3.0 Hz, 1H), 6.72 (dd, J = 9.0,3.0 Hz, 1H), 4.43-4.22 (m, 2H), 3.99-3.92 (m, 1H), 3.23-2.98 (m, 2H), 2.72(s, 3H), 2.04 (s, 3H), 1.78-1.65 (m, 4H). 13C NMR (151 MHz, DMSO-d6): δ164.33, 161.58, 160.17, 158.79, 147.16, 143.03, 140.51, 139.58, 139.33,138.17, 132.91, 131.50 (q, J C-F = 31.9 Hz), 130.54, 130.36, 129.05, 128.59(2C), 126.84, 125.48 (q, J C-F = 3.6 Hz, 2C), 123.91 (q, J C-F = 272.6 Hz),122.30, 115.87, 112.14, 109.71, 55.84, 31.41, 29.43, 28.71, 26.35, 22.10,16.54. ESI-HRMS m / z: calcd for C 32 H 30 F3N5O5S [M+H] + 654.1998; found 654.1993. HPLC purity 99.17 %.

[0233] Experimental Example 1: Antitumor Cell Proliferation Activity of the Compounds of the Present Invention

[0234] STAT3 is persistently activated in the human colon cancer cell line HCT-116. In this study, OPB-31121, a representative compound that directly targets STAT3 (possessing in vitro and in vivo efficacy and inhibiting STAT3 phosphorylation at Tyr705 and Ser727 sites), and the approved HDAC inhibitor SAHA were used as positive controls. The antiproliferative activity of the compounds of this invention, OPB-31121, and SAHA against HCT-116 was evaluated using the CCK-8 assay. Other compounds of this invention have similar beneficial effects to those listed below, but this should not be construed as meaning that the compounds of this invention only possess the following beneficial effects.

[0235] The assay for antitumor cell proliferation activity was performed as follows: HCT-116 cells were cultured in McCoy's 5a medium. HCT-116 cells in logarithmic growth phase (3 × 10⁻⁶ cells) were then... 3Cells were seeded in 96-well plates and cultured overnight (37 °C, 5% CO2). After cell attachment, the cells were co-incubated with solutions of varying concentrations of compounds for 72 h. An appropriate amount of CCK-8 solution was then added to each well, and incubation continued for another 4 h. After incubation, the supernatant was discarded, and the absorbance was measured at 450 nm. The IC50 was calculated using GraphPad Prism9 software. 50 Values. The antiproliferative activity of the preferred compounds against different tumor cells and their cytotoxicity against normal cells were evaluated in the same manner as HCT-116, and the results are shown in Table 1.

[0236] Table 1. Antitumor cell proliferation activity of the compounds

[0237] Table 1: "++++" represents 0.1-1.0 μM; "+++" represents 1.0-10 μM; "++" represents 10-20 μM; "+" represents 20-30 μM.

[0238] As shown in Table 1, all the listed compounds exhibited significant anti-proliferative activity against the HCT-116 cell line, and some compounds showed comparable or even better activity than the positive controls OPB-31121 and SAHA.

[0239] Experimental Example 2: Broad-spectrum anti-tumor cell proliferation activity of the compounds of the present invention

[0240] Using a similar assay method to the above-described tumor cell antiproliferative activity test, the antiproliferative activity of compound 17 against various STAT3-high expressing tumor cell lines (including solid tumors and hematologic malignancies) was further evaluated. Other compounds of the present invention have similar beneficial effects to those listed below, but this should not be construed as meaning that the compounds of the present invention only possess the following beneficial effects.

[0241] Table 2. Antiproliferative activity of the compounds against other tumor cells

[0242] In Table 2: "++++" represents 0.1-1.0 μM; "+++" represents 1.0-10 μM; "++" represents 10-20 μM; "+" represents 20-30 μM.

[0243] As shown in Table 2, the listed compounds exhibited significant anti-proliferative activity against six STAT3-overexpressing tumor cell lines other than HCT-116 (their anti-tumor cell proliferation activity against all cell lines was superior to OPB-31121 and SAHA, or comparable to the latter), indicating that the compounds have potential broad-spectrum anti-proliferative functions against STAT3-overexpressing tumor cells.

[0244] Experimental Example 3: SPR Experiment of the Compounds of the Invention

[0245] SPR (Surface Refractive Index) is a common biophysical technique for characterizing the affinity of compounds for target proteins. The principle is that when a small molecule compound flowing through a chip specifically binds to a protein immobilized on its surface, it affects the chip's surface refractive index. This effect reflects the small molecule's affinity for the protein. To confirm that the target molecule can indeed bind to STAT3, we used this technique to examine the binding affinity of compound 17 to STAT3. Other compounds of this invention have similar beneficial effects to compound 17, but this should not be construed as meaning that the compounds of this invention only possess the following beneficial effects.

[0246] The CM5 sensor chip was activated using an activator (containing 400 mM EDC and 100 mM NHS; flow rate 10 μL / min). Subsequently, immobilization buffer (10 mM sodium acetate, pH 4.5) containing STAT3 (50 μg / mL) was injected into the Fc2 sample channel at a flow rate of 10 μL / min to achieve an immobilization level of 3000 RU. The chip was inactivated by ethanolamine-HCl (1 M, flow rate 10 μL / min). Compound 17 was diluted to gradient concentrations using running buffer (1×PBS buffer containing 0.05% Tween-20 and 5% DMSO, pH 7.4) and injected into channels Fc1-Fc2 at a flow rate of 30 μL / min, binding for 90 s followed by dissociation for 210 s.

[0247] Compound 17 in this invention has a high affinity (K) for STAT3. D The concentration was 0.87 μM, confirming that the compound of the present invention is a STAT3 ligand that can directly interact with the STAT3 protein.

[0248] Experimental Example 4: Experiment on the ability of the compound of the present invention to inhibit STAT3 signal transduction

[0249] Phosphorylation at STAT3 Tyr705 and Ser727 sites plays a complementary and synergistic role in cancer development and progression, while p-STAT3 Tyr705 and p-STAT3 Ser727 are biomarkers of the classical and non-classical activation pathways of STAT3, respectively. Therefore, to further characterize that the compounds of this invention can indeed interfere with phosphorylation at Tyr705 and Ser727 sites after binding to STAT3, this experimental example uses Western blotting to examine the ability of compound 17 to inhibit the expression of these two phosphorylation forms. Other compounds of this invention have similar beneficial effects to compound 17, but this should not be construed as meaning that the compounds of this invention only have the following beneficial effects.

[0250] HCT-116 cells in logarithmic growth phase (5 × 10⁻⁶) 6 Cells (per well) were seeded in 6-well plates and cultured overnight (37 °C, 5% CO2). Different concentrations of compound 17 or OPB-31121 solution were added to each well for drug administration, while an equal volume of complete culture medium was added to the blank control wells. Cells were cultured for another 24 h. Cells were collected, proteins were extracted and separated by SDS-PAGE, and transferred to PVDF membranes, incubated sequentially with primary and secondary antibodies. ImageJ software was used to calculate grayscale values ​​and analyze the expression levels of STAT3 phosphorylation or HDAC substrate acetylation.

[0251] Figure 1 This indicates that compound 17 of the present invention can significantly inhibit phosphorylation at Tyr705 and Ser727 sites at concentrations as low as 1.0 μM. Therefore, the compound of the present invention can effectively intervene in intracellular STAT3 signaling by binding to STAT3 and simultaneously inhibiting phosphorylation at Tyr705 and Ser727 sites.

[0252] Experimental Example 5: Detection Experiment of the Inhibition of Intracellular ATP Production by the Compounds of the Present Invention

[0253] Phosphorylation of STAT3 at Ser727 can lead to increased mitochondrial ATP production in tumor cells. Given that compound 17 of this invention can inhibit STAT3 phosphorylation at Ser727, this study used an ATP assay kit to evaluate its inhibitory activity on ATP production in HCT-116 cells. Other compounds of this invention have similar beneficial effects to compound 17, but this should not be construed as meaning that the compounds of this invention only have the following beneficial effects.

[0254] HCT-116 cells were co-incubated with gradient concentrations of compound 17 and OPB-31121 for 24 h. Intracellular ATP production was quantitatively detected using a commercially available ATP assay kit (Beyotime, S0026), and the IC50 inhibitory concentration (IC50) for inhibiting ATP production was calculated. 50 value.

[0255] Figure 2 This indicates that compound 17 of the present invention can dose-dependently block ATP production (IC50) in HCT-116 cells. 50 = 0.73 μM), and its activity is superior to that of the positive control drug OPB-31121 (IC50). 50 = 1.41 μM). Consistent with the downregulation of p-STAT3 Ser727 expression, the compounds of this invention effectively inhibit ATP production in cells.

[0256] Experimental Example 6: Experiment on the inhibitory effect of the compound of the present invention on mitochondrial OXPHOS activity

[0257] Most tumors rely on OXPHOS to maintain their energy metabolism and drive disease progression. Given that phosphorylation of STAT3 at Ser727 leads to upregulation of mitochondrial OXPHOS, this study used the Seahorse assay to test the effect of compound 17 on mitochondrial OXPHOS in HCT-116 cells. Other compounds of this invention have similar beneficial effects to compound 17, but this should not be construed as meaning that the compounds of this invention only have the following beneficial effects.

[0258] HCT-116 cells in logarithmic growth phase (1×10⁻⁶) 5 Cells (cells / well) were seeded in XFp culture plates and cultured overnight (37°C, 5% CO2). Cells were co-incubated with different concentrations of Compound 17 solution for 24 h. OCR, basal OCR, maximum OCR, and ATP production rate were analyzed using the Seahorse XFSubOX kit and the Seahorse XFp analyzer.

[0259] Figure 3 This indicates that compound 17 of the present invention can inhibit mitochondrial OXPHOS in a dose-dependent manner. At concentrations as low as 0.33 μM, compound 17 significantly reduces both basal and maximal OCR. Consistent with the results of ATP inhibition experiments, the compounds of the present invention can regulate abnormal energy metabolism in tumor cells by inhibiting phosphorylation at the Ser727 site.

[0260] Experimental Example 7: Activity of the Compounds of the Present Invention in Inhibiting Representative HDAC Isotypes

[0261] The inhibitory effect of compound 17 on representative HDAC isoforms—HDAC1 and HDAC6—was evaluated using a fluorescence method. Other compounds of this invention have similar beneficial effects to those listed below, but this should not be construed as meaning that the compounds of this invention only possess the following beneficial effects.

[0262] The HDAC1 and HDAC6 inhibitory activities of compound 17 were determined using a fluorescence detection method. A 10 mM stock solution of the test compound was prepared from DMSO solution. Enzyme and substrate / trypsin solutions were prepared using buffer solutions. Gradient concentrations of the test compound solutions and enzyme solutions were incubated together in 384-well plates at room temperature for 15 min. Subsequently, the substrate / trypsin mixture was added to the detection plate to prepare the catalytic reaction system. Fluorescence values ​​were read using an Envision microplate reader to calculate the inhibition rate at each concentration. An XL-Fit curve was used to obtain the IC50 values. 50 value.

[0263] Table 3. Inhibitory activity of compounds against other representative HDAC isotypes

[0264] In Table 3: "++++" represents 5-10 nM; "+++" represents 10-50 nM; "++" represents 50-100 nM; "+" represents 100-200 nM.

[0265] As shown in Table 3, compound 17 can significantly inhibit the representative HDAC subtypes HDAC1 and HDAC6. Therefore, the compound of this invention is a dual-target inhibitor of STAT3 / HDAC that combines the phosphorylation regulation functions of Ser727 and Tyr705.

[0266] Experimental Example 8: Detection Experiment of Acetylation Level of HDAC Substrate by Compounds of the Present Invention

[0267] Histone H3 and α-tubulin are substrates of HDAC1 and HDAC6, respectively. To verify the inhibitory effect of compound 17 on HDAC in cells, this experiment used a similar testing method to the above-mentioned experiment on the ability to inhibit STAT3 signaling, and Western blotting was used to determine the effect of compound 17 on the expression of Ac-H3 and Ac-α-tubulin in cells. Other compounds of the present invention have similar beneficial effects to the compounds listed below, but this should not be construed as the compounds of the present invention having only the following beneficial effects.

[0268] Figure 4 This indicates that compound 17 of the present invention can significantly upregulate the expression levels of intracellular Ac-H3 and Ac-α-tubulin at concentrations as low as 2.0 μM. Therefore, compound 17 of the present invention can inhibit the deacetylation of intracellular HDAC substrates, i.e., it has an intracellular HDAC inhibitory effect.

[0269] Experimental Example 9: Detection Experiment of Cell Cycle and Apoptosis by Compounds of the Invention

[0270] Given that both STAT3 and HDACs are involved in tumor cell growth, survival, and proliferation, this experiment used flow cytometry to verify the effect of compound 17 on the cell cycle and apoptosis of HCT-116 cells. Other compounds of this invention have similar beneficial effects to those listed below, but this should not be construed as meaning that the compounds of this invention only have the following beneficial effects.

[0271] HCT-116 cells in logarithmic growth phase (5 × 10⁻⁶) 5Cells were seeded in 6-well plates and cultured overnight (37 °C, 5% CO2), followed by co-incubation for 72 h with OPB-31121, SAHA, or different concentrations of compound 17. Cells were then digested with 0.25% trypsin (without EDTA) and washed twice with PBS. The cell suspension was divided into two aliquots, one for cell cycle analysis. Pre-chilled 80% ethanol was added to this sample, and the cells were fixed overnight at 4 °C. After centrifugation at 1000 xg, the supernatant was discarded, and the cells were washed with PBS and resuspended in PBS. RNase A (20 μL) was added to the cell suspension, and the cells were incubated at 37 °C for 30 min. After centrifugation at 1000 xg again, the supernatant was discarded, and the pellet was resuspended in PI staining solution (400 μL). The cells were incubated at 4 °C in the dark for 30 min, and the cell cycle was analyzed using flow cytometry. The other cell suspension was used for apoptosis analysis using annexin V-FITC / PI double staining. Cells were resuspended in binding buffer (400 μL), and annexin V-FITC (5 μL) and PI (10 μL) were added sequentially. After incubation in the dark for 15 min, cell apoptosis was detected by flow cytometry.

[0272] Figure 5-7 This indicates that compound 17 in this invention arrests the cell cycle at the G0 / G1 phase and can dose-dependently increase the proportion of cells in the G0 / G1 phase and decrease the proportion of cells in the S phase. Annexin V-FITC / PI double staining results showed that it can dose-dependently increase the proportion of apoptotic cells. When the dose was 0.5 μM, the proportion of apoptotic HCT-116 cells reached 26.30%.

[0273] In summary, the compounds in this invention exhibit excellent anti-proliferative activity against a variety of cancer cells; they can simultaneously inhibit STAT3 and HDAC functions, and also possess Ser727 and Tyr705 phosphorylation regulatory functions. This class of dual-target inhibitors demonstrates significant anti-cancer potential.

Claims

1. A STAT3 / HDAC dual-target inhibitor, characterized in that, The STAT3 / HDAC dual-target inhibitors are compounds represented by formulas I-V or their pharmaceutically acceptable salts or deuterated derivatives. ； In the above formula: X is independently selected from -(CH2)n1-, where n1 = 1-7; Ring A is independently selected from aryl or five-membered heteroaryl; Ring B is independently selected from -COR1; The ring C is independently selected from -COR2 or R3; R1 is independently selected from at least a six-membered nitrogen-containing monoacid heterocyclic group or a seven- to nine-membered diazaspirocyclic group; R2 and R3 may be the same or different, and each is independently selected from at least aryl or five- to six-membered heteroaryl groups.

2. The STAT3 / HDAC dual-target inhibitor according to claim 1, characterized in that, n1 = any one of 1, 3 or 7.

3. The STAT3 / HDAC dual-target inhibitor according to claim 1, characterized in that, X is independently selected from -CH2-; ring A is independently selected from either phenyl or thiophene.

4. The STAT3 / HDAC dual-target inhibitor according to claim 1, characterized in that, X is independently selected from -CH2-; R1 is independently selected from any one of piperazinyl, 2,6-diazaspiro[3.3]heptyl, 2,6-diazaspiro[3.4]octyl or 2,7-diazaspiro[4.4]nonyl.

5. The STAT3 / HDAC dual-target inhibitor according to claim 1, characterized in that, R2 is independently selected from any one of phenyl, thiophene, or pyridinyl, and R3 is independently selected from pyrimidinyl.

6. The STAT3 / HDAC dual-target inhibitor according to claim 1, characterized in that, The STAT3 / HDAC dual-target inhibitor is selected from any of the following compounds or their pharmaceutically acceptable salts or deuterates.

7. A pharmaceutical composition comprising an effective amount of a STAT3 / HDAC dual-target inhibitor as described in any one of claims 1-6 or a pharmaceutically acceptable salt or deuterated thereof, and at least one pharmaceutically acceptable carrier or excipient.

8. The pharmaceutical composition according to claim 7, characterized in that, It also includes at least one other therapeutic agent, said other therapeutic agent being an immunotherapeutic agent.

9. The use of the STAT3 / HDAC dual-target inhibitor according to any one of claims 1-6, or a pharmaceutically acceptable salt or deuterated thereof, or the pharmaceutical composition according to claim 7 or 8, in the preparation of an antitumor drug.

10. The application according to claim 9, characterized in that, The tumors include breast cancer, cervical cancer, colorectal cancer, pancreatic cancer, esophageal squamous cell carcinoma, non-small cell lung cancer, ovarian cancer, lymphoma, acute myeloid leukemia, or chronic myeloid leukemia.

Images