Methods of making novel compounds

Abstract

This invention relates to a method for preparing 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine, a novel candidate for the treatment of NF2. Through an optimized preparation method, a low-impurity and high-purity compound can be prepared even with low manufacturing costs and short preparation time, and the compound thus prepared can be used as a novel therapeutic agent for neurofibromatosis type 2 (NF2).

Description

Technical Field

[0001] This disclosure relates to a method for preparing novel compounds, and more specifically, to a method for preparing 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine. Background Technology

[0002] Neurofibromatosis (NF) is a hereditary disease affecting the skeletal, soft tissue, skin, and nervous system, and is classified into neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2). Neurofibromatosis type 2 is characterized by benign tumors originating from the eighth cranial nerve, causing symptoms such as hearing loss, tinnitus, and balance disorders. Because it originates from Schwann cells within the central nervous system, it is also known as vestibular Schwannoma. The average age of onset for neurofibromatosis type 2 is 18 to 24 years, and it is known that almost all patients develop bilateral vestibular Schwannomas before the age of 30. In addition, Schwannomas of cranial and peripheral nerves, meningiomas, ependymomas, and, in rare cases, astrocytomas may also progress.

[0003] Neurofibromatosis type 2 is caused by a mutation in the NF2 gene located on the long arm of chromosome 22 (22q12.2). The NF2 gene encodes a protein called merlin, which is produced in Schwann cells surrounding nerve cells in the brain and spinal cord of the nervous system.

[0004] Meanwhile, Korean Patent Application Publication No. 10-2022-0128710 has discovered a novel compound for the treatment of neurofibromatosis type 2 (NF2), and research on the optimal preparation method of this compound is ongoing. Summary of the Invention Technical issues

[0005] The purpose of this disclosure is to provide an optimal method for preparing 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine. Technical solution

[0006] To achieve the above objective, this disclosure provides a method for preparing 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine, the method comprising: a) dissolving 4-MBC (4-methoxybenzyl chloride) in DMF (dimethylformamide), then adding NaN3 (sodium azide) and reacting for 1 to 3 hours to synthesize an intermediate; b-1) dissolving 4-HPA (4-hydroxyphenylacetonitrile) in THF (tetrahydrofuran), then adding DEAECl·HCl (2-diethylaminoethyl chloride) to the solution. b-1) Add NaOH aqueous solution to the reaction product of step b-1) and cool it to 5°C to 20°C; b-2) Add NaOH aqueous solution to the reaction product of step b-1) and react it for 2 to 4 hours to synthesize the intermediate; c) Dissolve the intermediate of step a) and the intermediate of step b-2) in DMSO, then add KTB (potassium tert-butoxide, t-BuOK) and react it at 20°C to 40°C for 1 to 3 hours; and d) Dissolve the reaction product of step c) in CH2Cl2 (dichloromethane), add activated carbon, stir it at 15°C to 40°C for 30 to 100 minutes, and filter and wash it. Beneficial effects

[0007] This disclosure relates to a method for preparing novel compounds for treating NF2, and through an optimal preparation method, compounds with high purity and high yield can be prepared with only a small amount of impurities, even with less preparation cost and preparation time. Attached Figure Description

[0008] Figure 1 A synthetic scheme for 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine (hereinafter referred to as PRG-N-01) is shown. Detailed Implementation

[0009] The following will describe this disclosure in more detail.

[0010] ​​

[0011] This disclosure provides a method for preparing 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine, the method comprising: a) dissolving 4-MBC (4-methoxybenzyl chloride) in DMF (dimethylformamide), then adding NaN3 (sodium azide) and reacting for 1 to 3 hours to synthesize an intermediate; b-1) dissolving 4-HPA (4-hydroxyphenylacetonitrile) in THF (tetrahydrofuran), then adding DEAECl·HCl (2-diethylaminoethyl chloride hydrochloride) and... a) Add water and cool it to 5°C to 20°C; b-2) Add NaOH aqueous solution to the reaction product of step b-1) and let it react for 2 to 4 hours to synthesize the intermediate; c) Dissolve the intermediate of step a) and the intermediate of step b-2) in DMSO, then add KTB (potassium tert-butoxide, t-BuOK) and let it react at 20°C to 40°C for 1 to 3 hours; and d) Dissolve the reaction product of step c) in CH2Cl2 (dichloromethane), add activated carbon, stir it at 15°C to 40°C for 30 to 100 minutes, and filter and wash it.

[0012] The reaction in step a) can be carried out at 15°C to 60°C, and preferably at 25°C to 30°C.

[0013] The amount of NaN3 used in step a) can be 1.0 to 3.0 equivalents, preferably 1.1 to 2.2 equivalents, and more preferably 1.5 equivalents.

[0014] The amount of DEAECl·HCl used in step b-1) can be 1.0 to 1.5 equivalents, and preferably 1.2 equivalents.

[0015] The reaction in step b-2) can be carried out at 40°C to 70°C, and preferably at 60°C to 65°C.

[0016] The amount of NaOH used in step b-2) can be 2.5 to 4 equivalents, and preferably 3.0 equivalents.

[0017] The NaOH aqueous solution in step b-2) can be from 20% (w / v) to 50% (w / v), preferably from 22% (w / v) to 45% (w / v), and more preferably 22.5% (w / v).

[0018] The amount of KTB used in step c) can be from 1.0 to 3.0 equivalents, and preferably 2.0 equivalents.

[0019] In step d), the volume ratio of the reaction product of step c) to CH2Cl2 (dichloromethane) can be from 1:1.5 to 1:4.0, and preferably 1:3. Embodiments of the present invention

[0020] The following will describe embodiments, etc., in detail to aid in understanding this disclosure. However, the following embodiments, etc., are merely illustrative of the content of this disclosure, and the scope of this disclosure is not limited to the following embodiments, etc. The embodiments of this disclosure are provided to explain this disclosure more completely to those skilled in the art.

[0021] ‌

[0022] [Preparation Example] Synthesis of PRG-N-01 Compound

[0023]

[0024] (1) Step 1: Synthesis of intermediate-1 (azide)

[0025] Weigh 4-MBC (4-methoxybenzyl chloride, 638.5 mmol, 100 g) into a round-bottom flask, add DMF (dimethylformamide, 1000 mL) and dissolve. Once the reactants are completely dissolved, add NaN3 (957.8 mmol, 62.3 g) and allow to react at 25°C to 30°C for 2 hours. Cool the reaction solution to 5°C to 10°C, then slowly add purified water (2500 mL). Transfer the reaction solution to a separatory funnel, extract with IPE (isopropyl ether, 2500 mL), and remove residual water with anhydrous magnesium sulfate. Concentrate the reaction solution under reduced pressure and use it for the next reaction without further purification.

[0026] HPLC analysis results: 98.5% area.

[0027] ‌

[0028] (2) Step 2: Synthesis of intermediate-2 (cyanide)

[0029] Weigh 4-HPA (4-hydroxyphenylacetonitrile) (851.2 mmol, 113.3 g) into a round-bottom flask, add THF (tetrahydrofuran, 1133 mL) and dissolve. Once the reactant is completely dissolved, add DEAECl·HCl (2-diethylaminoethyl chloride hydrochloride, 1021.4 mmol, 175.8 g) and purified water (226 mL), and cool the reactant to 10°C to 20°C. Slowly add a solution of NaOH (2553.5 mmol, 102.1 g) dissolved in purified water (453 mL) to the reaction solution, then raise the temperature to 60°C to 65°C and allow it to react for 3 hours. Cool the reaction solution to 20°C to 30°C, then transfer the reaction product to a separatory funnel to collect the organic layer, and remove residual water with anhydrous magnesium sulfate. Concentrate the reaction solution under reduced pressure and use it for the next reaction without further purification.

[0030] HPLC analysis results: 99.2% area.

[0031] ‌

[0032] (3) Step 3: Synthesis of crude PRG-N-01

[0033] Weigh intermediate-1 (azide, 625.8 mmol, 102.1 g) and intermediate-2 (Cyano, 817.1 mmol, 189.8 g) into a round-bottom flask, add DMSO (706.3 mL) and dissolve. Cool the reaction mixture to 10-15°C, slowly add KTB (potassium tert-butoxide, 1251.5 mmol, 140.4 g), then raise the temperature to 20-30°C and allow it to react for 2 hours. Cool the reaction solution again to 10-15°C, then slowly add purified water (1020 mL). Transfer the reaction solution to a separatory funnel, extract with CH2Cl2 (1020 mL), and wash with 20% saline (280 mL). Remove residual water with anhydrous magnesium sulfate. After concentration under reduced pressure, crystallization was carried out using CH2Cl2 (150 mL) and IPE (isopropyl ether, 2040 mL).

[0034] HPLC analysis results: 99.1% area.

[0035] Yield: 80% overall, beige solids.

[0036] ‌

[0037] (4) Step 4: Synthesis of PRG-N-01

[0038] Weigh 500.6 mmol (200 g) of crude PRG-N-01 into a round-bottom flask, add 600 mL of CH2Cl2 and dissolve. After the reactant is completely dissolved, add 10 wt% (20 g) of activated carbon and stir for 1 hour at 20-30°C. Filter the reactant through a Celite filtration membrane and wash thoroughly with CH2Cl2 to recover the organic layer. After concentration under reduced pressure, crystallize using 600 mL of CH2Cl2 and IPE (isopropyl ether, 2400 mL).

[0039] HPLC analysis results: 99.8% area.

[0040] Yield: 90%, white solid.

[0041] ¹H-NMR (400 MHz, DMSO-d6) δ: 7.62 (d, 2H), 7.23 (d, 2H), 6.95 (d, 2H), 6.91 (d, 2H), 5.65 (s, 2H ), 5.36 (s, 2H), 4.02 (t, 2H), 3.72 (s, 3H), 2.77 (t, 2H), 2.55 (q, 4H), 0.97 (t, 6H).

[0042] ‌

[0043] [Experimental Example 1] Optimization Study of Intermediate-1 (Azide) Synthesis

[0044]

[0045] Intermediate-1 (azide) was synthesized in the same manner as step 1 of the above embodiment, and the results were analyzed by HPLC. The HPLC operating conditions and details are as follows.

[0046] ‌

[0047] Detector: Ultraviolet absorption spectrometer (measurement wavelength: 226 nm).

[0048] Column: Agilent eclipse plus C8 (4.6 mm × 250 mm, 5 μm).

[0049] Column temperature: kept constant at around 40℃.

[0050] Mobile phase A: 20 mM sodium octane sulfonate in water.

[0051] Mobile phase B: 0.01% TFA in acetonitrile.

[0052] [Table 1]

[0053] Flow rate: 0.8 mL / min, analysis time: 48 minutes.

[0054] Diluent: 100% methanol.

[0055] Sample concentration: Place 100 mg of sample in a 100 mL volumetric flask, add diluent and dissolve, then bring the volume to the mark.

[0056] Injection volume: 5 μL.

[0057] ‌

[0058] (1) Effect of reaction solvent on the induction of intermediate-1 (azide) synthesis

[0059] [Table 2]

[0060] The reaction was carried out in the same manner as step 1 of the above embodiment using DMF, acetonitrile (ACN), acetone (ACT), and tetrahydrofuran (THF). When the reaction was carried out using acetonitrile, acetone, and tetrahydrofuran solvents, an unknown peak appeared, while when the reaction was carried out using DMF solvent, no unknown peak was observed, and it can be confirmed that the reaction was completed in just 2 hours.

[0061] (2) Effect of reaction temperature on the synthesis of induced intermediate-1 (azide)

[0062] [Table 3]

[0063] Using the same method as step 1 of the above embodiment, it was confirmed that there was residue of the raw material (4-MBC) within the reaction temperature range of 5°C to 10°C, while the reaction could be completed in 2 hours within other temperature ranges, and there was no significant difference in purity. Therefore, the reaction temperature was set to 25°C to 30°C, which was considered a suitable reaction condition.

[0064] (3) Effect of NaN3 usage on the synthesis of induced intermediate-1 (azide).

[0065] [Table 4]

[0066] The amount of NaN3 used to synthesize intermediate-1 (azide) was tested in the same manner as in step 1 of the above embodiment. The results confirmed that when used in the range of 1.1 to 3.0 equivalents, the reaction was completed within 2 hours in all cases. Theoretically, NaN3 and 4-MBC (4-methoxybenzyl chloride) react in a 1:1 ratio, and there is no problem even when an excess of 3 equivalents of NaN3 is used; however, setting the amount of NaN3 used to 1.5 equivalents represents an intermediate range.

[0067] [Experimental Example 2] Optimization Study of Intermediate-2 (Cyano) Synthesis

[0068]

[0069] Intermediate-2 (Cyano) was synthesized in the same manner as step 2 of the above embodiment, and the results were analyzed by HPLC.

[0070] ‌

[0071] (1) Effect of reaction temperature on the synthesis of induced intermediate-2 (Cyano)

[0072] [Table 5]

[0073] Following the same procedure as step 2 of the above embodiment, it was confirmed that the reaction was completed within 2 to 3 hours in the temperature range of 40°C to 65°C. In the reaction at 60°C to 65°C, it was confirmed that the reaction rate of the conversion of the starting material (4-HPA) to cyanide was rapid, and the amount of the generated unknown impurity-2 (hereinafter referred to as UK-2) was relatively small. Therefore, it was confirmed that it is advantageous to terminate the reaction in a shorter time due to this reaction temperature.

[0074] (2) Effect of inorganic base type on the synthesis of induced intermediate-2 (Cyano)

[0075] [Table 6]

[0076] In the same manner as step 2 of the above embodiment, when K2CO3 is used in an amount of 2.85 equivalents or more, the reaction proceeds without problems, but there is a disadvantage of a large amount of inorganic base to be added. In the case of NaOH, the reaction proceeds optimally at 3 equivalents, and this is advantageous due to the relatively small molecular weight of NaOH. In particular, when a 22.5% (w / v) NaOH solution is added, impurity formation is minimized at RT for 12 minutes, therefore the inorganic base is set to be added as NaOH solution.

[0077] (3) Effect of DEAECl·HCl (2-diethylaminoethyl chloride hydrochloride) dosage on the synthesis of induced intermediate-2 (Cyano)

[0078] [Table 7]

[0079] Following the same procedure as step 2 of the above embodiment, when the amount of DEAECl·HCl used was changed from 1.1 to 1.5 equivalents and experiments were conducted, the results confirmed that the reaction at 65°C yielded suitable results at only 1.1 equivalents. Therefore, it was confirmed that the amount of DEAECl·HCl used to convert all 4-HPA to cyano and minimize the generation of UK-2 impurities was 1.2 equivalents.

[0080] [Experimental Example 3] Optimization Study on the Synthesis of Crude PRG-N-01

[0081]

[0082] The crude PRG-N-01 was synthesized in the same manner as step 3 of the above embodiment, and the results were analyzed by HPLC.

[0083] ‌

[0084] (1) Effect of reaction solvent on the induction of crude PRG-N-01 synthesis

[0085] [Table 8]

[0086] The cyanation reaction was carried out using THF, DMSO, DMF, and IPE-THF solvents in the same manner as step 3 of the above embodiment. When tetrahydrofuran (THF) was used as the reaction solvent, a large amount of unknown impurities were generated, resulting in low product purity and the formation of viscous brown crystals after crystallization. When DMF was used as the reaction solvent, the amount of unknown impurity-3 (hereinafter referred to as UK-3) increased, leading to low overall product purity. When DMSO was used as the reaction solvent, the purity of the product during synthesis was optimal, and most of the generated impurities were removed during post-processing; therefore, DMSO was chosen as the reaction solvent.

[0087] (2) Effect of inorganic base type on the induction of crude PRG-N-01 synthesis

[0088] [Table 9]

[0089] Following the same procedure as step 3 of the above embodiment, experiments were conducted on the inorganic base used to synthesize crude PRG-N-01. The reactivity was significantly lower with KOH, and the reaction failed to proceed with DBU (1,8-diazabicyclo[5.4.0]undec-7-ene). While results meeting the required standards were confirmed when reacting with NaOH and NaOEt, problems with stirring difficulties due to increased reactant viscosity were also identified. Therefore, KTB was chosen as the inorganic base for synthesizing crude PRG-N-01.

[0090] (3) Effect of KTB (potassium tert-butoxide, t-BuOK) dosage on the induced synthesis of crude PRG-N-01

[0091] [Table 10]

[0092] Following the same procedure as step 3 of the above embodiment, as a result of experiments on the amount of KTB used to synthesize crude PRG-N-01, it was confirmed that the level met the standard in all cases when KTB was used in the range of 1.5 to 3.0 equivalents. Furthermore, since UK-3 was completely removed after crystallization, it was determined that there were no issues with purity, and therefore the amount of KTB used was set to 2.0 equivalents.

[0093] (4) Effect of the order of raw material addition on the induction of crude PRG-N-01 synthesis

[0094] [Table 11]

[0095] As a result of proceeding in the same manner as step 3 of the above embodiments, in the case of item 3 in Table 11, it was confirmed that an unknown side reaction occurred when the reaction was carried out in the order of azide > KTB > Cyano. In the case of item 2 in Table 11, although the exothermic reaction was controlled when KTB was added to the cyano reactant and an azide solution in DMSO was slowly added, continuous exothermic reaction was observed during the addition of the azide in DMSO, and the final product was confirmed to be yellow in appearance.

[0096] As shown in item 1 of Table 11, an exothermic reaction of approximately 25°C was observed when KTB was added to the azide and Cyano reactants. However, when the initial exothermic reaction was controlled by adding KTB in batches (1% of the total amount to be added), no further exothermic reaction was observed. Therefore, the order in which KTB was added to the azide and Cyano reactants was determined.

[0097] ‌

[0098] [Experimental Example 4] Optimization Study of PRG-N-01 Synthesis

[0099]

[0100] PRG-N-01 was synthesized in the same manner as step 4 of the above embodiment, and the results were analyzed by HPLC.

[0101] ‌

[0102] (1) Effect of CH2Cl2 dosage on the induction of PRG-N-01 purification

[0103] [Table 12]

[0104] * vol refers to the volume measured using an amount equivalent to XX times the weight of PRG-N-01. Example: Purification of 1 kg of PRG-N-01 → 1.5 vol of CH2Cl2 = 1.5 L

[0105] Experiments were conducted in the same manner as step 4 of the above embodiments to confirm the purification effect based on the amount of CH2Cl2 used. The results confirmed that with increasing CH2Cl2 usage, better decolorization was achieved when IPE was added after the reactants were dissolved to induce crystal formation. When IPE was added at 1.5 vol after dissolution, a large amount of solid precipitated at once, while when IPE was added after dissolving in CH2Cl2, the solid precipitated slowly, thus being more effective in improving purity and appearance. Reflux was performed, confirming improved purity, but with a significant decrease in yield. Therefore, when purifying crude PRG-N-01, the amount of CH2Cl2 used was set to 3 vol, which is an intermediate value between 1.5 and 4 vol.

[0106] ‌

[0107] (2) Effect of activated carbon type on the induction of PRG-N-01 purification

[0108] [Table 13]

[0109] Experiments were conducted in the same manner as step 4 of the above embodiment to confirm the purification effect based on the type of activated carbon. The results showed that impurities were removed by carbon (impurity carbon) treatment for 12.38 minutes at RT using Shinki carbon (Shinki Chemical Industry, Korea), neutral carbon (Norit, Japan), and SA-20 (MEADWESTVACO, USA). Among these, the purity obtained after treatment with Shinki carbon was confirmed to be the best; therefore, Shinki carbon was chosen for purification.

[0110] The above description of this disclosure is merely illustrative, and those skilled in the art will understand that this disclosure can be readily modified into other specific forms without altering its technical spirit or key features. Therefore, it should be understood that the above embodiments are illustrative in all respects and not restrictive.

[0111] The scope of this disclosure is shown by the following claims, and all variations or modifications derived from the meaning and scope of the claims and their equivalents shall be construed as being included within the scope of this disclosure.

Claims

1. A method for preparing 4-(4-(2-(diethylamino)ethoxy)phenyl)-1-(4-methoxybenzyl)-1H-1,2,3-triazol-5-amine, comprising: a) Dissolve 4-MBC (4-methoxybenzyl chloride) in DMF (dimethylformamide), then add NaN3 (sodium azide) and react for 1 to 3 hours to synthesize an intermediate; b-1) Dissolve 4-HPA (4-hydroxyphenylacetonitrile) in THF (tetrahydrofuran), then add DEAECl·HCl (2-diethylaminoethyl chloride hydrochloride) and water, and cool it to 5°C to 20°C; b-2) Add NaOH aqueous solution to the reaction product of step b-1) and allow it to react for 2 to 4 hours to synthesize the intermediate; c) Dissolve the intermediates from step a) and step b-2) in DMSO, then add KTB (potassium tert-butoxide, t-BuOK) and react at 20°C to 40°C for 1 to 3 hours; and d) Dissolve the reaction product of step c) in CH2Cl2 (dichloromethane), add activated carbon, stir at 15°C to 40°C for 30 to 100 minutes, and then filter and wash it.

2. The method of claim 1, wherein, The reaction in step a) is carried out at 15°C to 60°C.

3. The method of claim 1, wherein, The amount of NaN3 used in step a) is 1.0 to 3.0 equivalents.

4. The method of claim 1, wherein, The amount of DEAECl·HCl used in step b-1) is 1.0 to 1.5 equivalents.

5. The method of claim 1, wherein, The reaction in step b-2) is carried out at 40°C to 70°C.

6. The method of claim 1, wherein, The amount of NaOH used in step b-2) is 2.5 to 4 equivalents.

7. The method of claim 1, wherein, The NaOH aqueous solution in step b-2) is a 20% (w / v) to 50% (w / v) NaOH aqueous solution.

8. The method of claim 1, wherein, The amount of KTB used in step c) is between 1.0 and 3.0 equivalents.

9. The method of claim 1, wherein, In step d), the volume ratio of the reaction product of step c) to CH2Cl2 (dichloromethane) is 1:1.5 to 1:4.0.

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