Cyclic leucine amide derivative and application thereof

Abstract

The invention discloses a cyclic leucine amide compound as well as a pharmaceutical composition and application thereof. The cyclic leucine amide derivative provided by the invention has PDK1 inhibitory activity, and the compound has a good application prospect in preparation of antitumor drugs.

Description

Technical Field

[0001] The present invention belongs to the field of pharmaceuticals, and provides a class of cyclo-leucinamide compounds, their preparation methods and pharmaceutical uses. These compounds have PDK1 inhibitory activity and have application prospects for preparing anti-tumor drugs. Background Art

[0002] According to the 2019 statistical data of the World Health Organization, cancer is the first or second leading cause of death in 112 countries (CA CANCER J CLIN 2021; 71: 209–249). Moreover, in the next 20 years, the number of newly diagnosed cancer cases globally is expected to increase by approximately 50%. In recent years, with the in-depth understanding of the basic mechanisms of cancer, significant progress has been made in targeted therapy for some tumor indications. However, the huge unmet clinical needs still suggest that continuous research and development of new anti-tumor drugs are needed.

[0003] The PI3K / Akt / mTOR signaling pathway is abnormally expressed in tumor cells and plays an important role in tumor growth, survival and tumor angiogenesis. Kinase inhibitors of certain nodes (such as PDKl, Akt, mTOR) in this pathway have become the focus of current anti-tumor drug research. 3-Phosphoinositide-dependent protein kinase-1 (PDK1) can activate 23 downstream kinases, and at the same time can continuously phosphorylate substrates, causing conformational changes in the substrates, exposing the anchoring sites, and enhancing the binding degree with PDK1. PDK1 has become an important target for anti-tumor drugs. Sodium dichloroacetate (DCA) is used as a specific PDK1 inhibitor for the treatment of malignant tumors. However, long-term application of this drug will cause clinical side effects such as peripheral neurotoxicity.

[0004] Therefore, novel small molecule PDK1 inhibitors have good application prospects in the treatment of malignant tumors. Summary of the Invention

[0005] Technical Problem to be Solved: The present invention provides a class of cyclo-leucinamide compounds, which have 3-phosphoinositide-dependent protein kinase-1 (PDK1) inhibitory activity and can be used to prepare drugs for treating malignant tumors.

[0006] Technical Solution: A class of cyclo-leucinamide compounds of formula I or their pharmaceutically acceptable salts, hydrates or solvates:

[0007]

[0008] Wherein, R1 is selected from C1-C6 alkyl or substituted phenyl; R2 is selected from hydrogen or C1-C3 alkyl; R3 is selected from hydrogen or C1-C3 alkyl.

[0009] Preferably, R1 is selected from C1-C3 alkyl or substituted phenyl; R2 is selected from hydrogen or C1-C3 alkyl; R3 is selected from hydrogen or C1-C3 alkyl.

[0010] More preferably, R1 is selected from methyl, ethyl, phenyl substituted with trifluoromethoxy; R2 and R3 are simultaneously selected from hydrogen, or R2 and R3 are simultaneously selected from methyl.

[0011] Most preferably, the compound is a compound selected from the following group or a pharmaceutically acceptable salt thereof:

[0012]

[0013] Compound 1: as shown in S1;

[0014]

[0015] Compound 2: as shown in S2;

[0016]

[0017] Compound 3: as shown in S3.

[0018]

[0019] The compound provided by the present invention further includes a pharmaceutically acceptable equivalent of the compound or a mixture of two or more thereof.

[0020] Preferably, the compound provided by the present invention may include one or a mixture of two or more of a pharmaceutically acceptable salt, hydrate, and solvate.

[0021] Preferably, the compound provided by the present invention includes an acid salt or a base salt of the compound provided by the present invention. The pharmaceutically acceptable salt has the pharmaceutical activity of the compound and meets the requirements both biologically and in practical applications.

[0022] The present invention provides a class of cyclo-leucinamide compounds or pharmaceutically acceptable salts thereof for treating tumors.

[0023] Beneficial effects:

[0024] A class of cyclo-leucinamide compounds described in the present application are characterized by having PDK1 inhibitory activity and can be used to prepare drugs for treating tumors. Detailed implementation manners

[0025] The present invention discloses cyclo-leucinamide compounds and their uses. Those skilled in the art can draw on the content of this article and appropriately improve process parameters to achieve them. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments. Relevant personnel can obviously make changes or appropriate alterations and combinations to the methods and applications described herein without departing from the content, spirit, and scope of the present invention to implement and apply the technology of the present invention.

[0026] To enable those skilled in the art to better understand the technical solutions of the present invention, the following further detailed description of the present invention is provided in conjunction with specific embodiments.

[0027] The general formula compounds of the present invention can be synthesized through the following route:

[0028]

[0029] Example 1: Synthesis of Compound S1

[0030]

[0031]

[0032] Step 1: Synthesis of Intermediate B1

[0033] Add A (1.05 g, 4.60 mmol), EDCI (1.32 g, 6.90 mmol), HOBT (0.93 g, 6.90 mmol) and 30 ml of dichloromethane into a reaction flask, stir at room temperature for 1 h, then successively add DIPEA (1.52 g, 11.50 mmol) and ethylamine (0.25 g, 5.55 mmol), stir at room temperature for 12 h, detect by TLC, when the reaction is complete, add 20 ml of water for washing, wash with saturated NaCl, dry with anhydrous Na2SO4, filter, rotary evaporate, and purify the crude product by silica gel column chromatography (petroleum ether:ethyl acetate = 5:1) to obtain 0.84 g of white solid, with a yield of 71%.

[0034] Step 2: Synthesis of Intermediate C1

[0035] Add B1 (0.89 g, 3.48 mmol), 20 ml of dichloromethane, and trifluoroacetic acid (5.00 ml, 65.40 mmol) into a reaction flask, heat up to 30 °C, stir for 2 h, detect by TLC, when the reaction is complete, directly rotary evaporate the reaction solution to obtain 1.34 g of yellow oily substance C1 (containing trifluoroacetic acid), and calculate the yield as 100%, which is directly used for the next step.

[0036] Step 3: Synthesis of the Final Product S1

[0037] Add C1 (1.34 g, 3.48 mmol) and 30 ml of dichloromethane to a reaction flask. Cool the temperature to 0 - 5 °C, and successively add triethylamine (1.10 g, 11.40 mmol) and diketene (0.32 g, 3.92 mmol). Raise the temperature to room temperature and stir for 12 h. Detect by TLC. After the reaction is complete, rotary evaporate the reaction solution. Purify the residue by silica gel column chromatography (dichloromethane:methanol = 10:1) to obtain 0.50 g of white solid with a yield of 60%.

[0038] ESI-MS: 241.14 [M+H] +

[0039] 1 H NMR (400 MHz, DMSO-d6) δ 8.13 (s, 1H), 7.57 (t, J = 5.6 Hz, 1H), 3.38 (s, 2H), 3.10–3.02 (m, 2H), 2.16 (s, 3H), 2.04–1.94 (m, 2H), 1.89–1.80 (m, 2H), 1.61 (dq, J = 7.5, 3.5 Hz, 4H), 0.99 (t, J = 7.2 Hz, 3H).

[0040] Example 2: Synthesis of Compound S2

[0041]

[0042]

[0043] Step 1: Synthesis of Intermediate B1

[0044] Add A (1.05 g, 4.60 mmol), EDCI (1.32 g, 6.90 mmol), HOBT (0.93 g, 6.90 mmol) and 30 ml of dichloromethane to a reaction flask. Stir at room temperature for 1 h, then successively add DIPEA (1.52 g, 11.50 mmol) and ethylamine (0.25 g, 5.55 mmol). Stir at room temperature for 12 h. Detect by TLC. After the reaction is complete, add 20 ml of water for washing, wash with saturated NaCl, dry with anhydrous Na2SO4, filter, rotary evaporate, and purify the crude product by silica gel column chromatography (petroleum ether:ethyl acetate = 5:1) to obtain 0.84 g of white solid with a yield of 71%.

[0045] Step 2: Synthesis of Intermediate C1

[0046] B1 (0.89 g, 3.48 mmol), 20 ml of dichloromethane, and trifluoroacetic acid (5.00 ml, 65.40 mmol) were added to a reaction flask. The temperature was raised to 30 °C and stirred for 2 h. TLC detection showed that the reaction was complete. The reaction solution was directly evaporated to dryness to obtain 1.34 g of yellow oil C1 (containing trifluoroacetic acid). The yield was calculated as 100% and was directly used for the next step.

[0047] Synthesis of Intermediate D1 in Step 3

[0048] C1 (1.34 g, 3.48 mmol) and 30 ml of dichloromethane were added to a reaction flask. The temperature was lowered to 0 - 5 °C, and triethylamine (1.10 g, 11.40 mmol) and diketene (0.32 g, 3.92 mmol) were added sequentially. The mixture was stirred at room temperature for 12 h. TLC detection showed that the reaction was complete. The reaction solution was evaporated to dryness, and the residue was purified by silica gel column chromatography (dichloromethane:methanol = 10:1) to obtain 0.50 g of white solid with a yield of 60%.

[0049] Synthesis of Final Product S2 in Step 4

[0050] D1 (1.12 g, 4.65 mmol), potassium carbonate (1.40 g, 10.22 mmol), and 30 ml of DMF were added to a reaction flask equipped with a U-shaped drying tube. The mixture was stirred at room temperature for 1 h, then iodomethane (2.62 g, 18.60 mmol) was added. TLC detection showed that the reaction was complete. 40 ml of water and 40 ml of ethyl acetate were added, and the mixture was stirred and separated. The ethyl acetate phase was retained, washed with saturated NaCl aqueous solution, dried over anhydrous Na2SO4, filtered, evaporated, and the crude product was purified by silica gel column chromatography (ethyl acetate:petroleum ether = 10:1) to obtain 0.81 g of yellow oil with a yield of 65%.

[0051] ESI-MS: 269.34 [M + H] +

[0052] 1 H NMR (400 MHz, DMSO-d6) δ 8.13 (s, 1H), 7.57 (t, J = 5.6 Hz, 1H), 3.38 (s, 2H), 2.16 (s, 3H), 2.04–1.94 (m, 2H), 1.89–1.80 (m, 2H), 1.87–1.76 (m, 6H), 1.61 (dq, J = 7.5, 3.5 Hz, 4H), 0.99 (t, J = 7.2 Hz, 3H).

[0053] Example 3: Synthesis of Compound S3

[0054]

[0055] Synthesis of Intermediate B2 in Step 1

[0056] A (1.05 g, 4.60 mmol), EDCI (1.32 g, 6.90 mmol), HOBT (0.93 g, 6.90 mmol) and 30 mL of dichloromethane were added to a reaction flask, and the mixture was stirred at room temperature for 1 h. Then, DIPEA (1.52 g, 11.50 mmol) and 4-trifluoromethoxyaniline (0.98 g, 5.55 mmol) were added successively, and the mixture was stirred at room temperature for 12 h. TLC detection showed that the reaction was complete. Then, 20 mL of water was added for washing, followed by saturated NaCl washing, and drying over anhydrous Na2SO4. After filtration and rotary evaporation, the crude product was purified by silica gel column chromatography (petroleum ether:ethyl acetate = 5:1) to obtain 1.27 g of a white solid with a yield of 71%.

[0057] Synthesis of Intermediate C2 in Step 2

[0058] B1 (1.35 g, 3.48 mmol), 20 mL of dichloromethane, and trifluoroacetic acid (5.00 mL, 65.40 mmol) were added to a reaction flask. The temperature was raised to 30 °C and the mixture was stirred for 2 h. TLC detection showed that the reaction was complete. The reaction solution was directly rotary evaporated to obtain 1.45 g of a yellow oil C1 (containing trifluoroacetic acid), and the yield was calculated as 100%. It was directly used for the next step.

[0059] Synthesis of Final Product S2 in Step 3

[0060] C1 (1.45 g, 3.48 mmol) and 30 mL of dichloromethane were added to a reaction flask. The temperature was lowered to 0 - 5 °C, and triethylamine (1.10 g, 11.40 mmol) and diketene (0.32 g, 3.92 mmol) were added successively. The mixture was stirred at room temperature for 12 h. TLC detection showed that the reaction was complete. The reaction solution was rotary evaporated, and the residue was purified by silica gel column chromatography (dichloromethane:methanol = 10:1) to obtain 0.78 g of a white solid with a yield of 60%.

[0061] ESI-MS: 373.13 [M+H] +

[0062] 1 1H NMR (400 MHz, DMSO-d6) δ 9.59 (s, 1H), 8.40 (s, 1H), 7.79–7.73 (m, 2H), 7.35–7.29 (m, 2H), 3.47 (s, 2H), 2.20 (s, 3H), 2.13 (td, J = 8.5, 4.0 Hz, 2H), 1.96–1.87 (m, 2H), 1.72–1.64 (m, 4H).

[0063] Example 4 Activity Test of Compound PDK1

[0064] To each 1.25 ml tube of 6 μM substrate peptide, add 100 μl of 10 mM ATP to make a 2X ATP / substrate mixture. Add 1 ml of 10X kinase buffer to 1.5 ml of double-distilled water to make 2.5 ml of 4X reaction buffer. Transfer 1.2 ml of 4X reaction buffer to each enzyme tube for a 4X reaction. Add 12.5 μl of 4X reaction mixture to 12.5 μl / well of the target compound and incubate at room temperature for 5 minutes. Add 25 μl of 2X ATP / substrate mixture to 25 μl / well of the pre-incubated reaction mixture / compound, and incubate the reaction plate at room temperature for 30 minutes. Add 50 μl / well of termination buffer (50 mM EDTA, pH 8) to terminate the reaction. Transfer 25 μl of each reaction to a 96-well streptavidin-coated plate containing 75 μl of dH2O / well and incubate at room temperature for 60 minutes. Wash three times with 200 μl / well of PBS / T. Dilute the primary antibody, Phospho-PKAC (Thr197) antibody, 1:1000 in PBS / T containing 1% BSA and add 100 μl / well of the primary antibody. Incubate at room temperature for 120 minutes, wash three times with 200 μl / well of PBS / T. Prepare an appropriate dilution of the Eu-labeled secondary antibody in PBS / T containing 1% BSA (dilution of anti-mouse IgG is 1:500, dilution of anti-rabbit IgG is 1:1000). Add 100 μl / well of the secondary antibody solution and incubate at room temperature for 30 minutes. Wash five times with 200 μl / well of PBS / T, add 100 μl / well of DELFIA enhancement and incubate at room temperature for 5 minutes. Read the plate using a time-resolved fluorescence plate reader.

[0065] The IC50 values of the test compounds were calculated using the statistical software GraphPad Prism 7.

[0066] Results: The PDK1 activity results of the compounds are shown in the following table:

[0067] Serial number Compound number PDK1 IC50 (μM) 1 S1 ++ 2 S2 ++ 3 S3 ++

[0068] ++ represents an IC50 of 10 - 50 μM; +++ represents an IC50 of 1 - 10 μM.

Claims

1. A class of cyclo-leucinamide compounds represented by formula I or a pharmaceutically acceptable salt, hydrate or solvate thereof: Among them, R1 is selected from C1-C6 alkyl or substituted phenyl; R2 is selected from hydrogen or C1-C3 alkyl; R3 is selected from hydrogen or C1-C3 alkyl.

2. Any of the compounds according to claim 1, characterized in that: Among them, R1 is selected from C1-C3 alkyl or substituted phenyl; R2 is selected from hydrogen or C1-C3 alkyl; R3 is selected from hydrogen or C1-C3 alkyl.

3. Any of the compounds according to claim 1, characterized in that: Among them, R1 is selected from methyl, ethyl, phenyl substituted with trifluoromethoxy; R2 and R3 are both selected from hydrogen, or R2 and R3 are both selected from methyl.

4. The compound according to claim 1, wherein The compound is a compound selected from the following group or a pharmaceutically acceptable salt thereof: Compound 1: as shown in S1; Compound 2: as shown in S2; Compound 3: as shown in S3.

5. Use of the compound according to any one of claims 1 to 4 or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating tumors.

6. A pharmaceutical composition, characterized in that, Comprising the compound according to any one of claims 1 to 4 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier.

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