Impurity compound of dotenorad and preparation and detection method thereof

Abstract

The invention belongs to the technical field of medicines, and particularly relates to an impurity compound of dotenorad as well as a preparation method and a detection method of the impurity compound. Specifically, a new compound impurity (I) is provided, the process of the step is optimized to reduce generation of the impurity, a good warning effect is achieved, detailed research on removal and transmission of the impurity in subsequent synthesis of a dotenorad raw material medicine is facilitated, and the impurity is prevented from being transmitted into the raw material medicine. The invention also provides a preparation method and a detection method of the impurity (I) and application of the impurity (I) in quality analysis of dotenorad raw material medicines and preparations thereof.

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical technology, specifically relating to an impurity compound of dotenoroxetine and its preparation and detection methods. Background Technology

[0002] Adverse reactions to drugs during clinical use are not only related to the pharmacological activity of the drug itself, but sometimes also to impurities present in the drug. Therefore, conducting standardized impurity studies is directly related to the quality and safety of marketed drugs.

[0003] Dotinurad, chemically known as 2-[(5-bromo-4-cyano-1H-pyrazol-1-yl)methyl]-4-(4-methoxyphenyl)-1,2,4-triazol-3-thione, is a selective uric acid transporter 1 (URAT1) inhibitor developed by Fuji Pharmaceutical in Japan. It was first approved for marketing in Japan in 2020 under the brand name URECE. In 2023, it entered the clinical trial stage in China, with the indication of hyperuricemia with gout. It promotes uric acid excretion and lowers blood uric acid levels by inhibiting URAT1-mediated uric acid reabsorption in renal tubular epithelial cells. It has higher selectivity for URAT1 than similar drugs (such as febuxostat), requires a low daily dose (the usual dose is 2 mg / day), and has less impact on renal function. It is suitable for patients with mild to moderate renal insufficiency. As a new generation drug in the field of gout treatment, it can make up for the shortcomings of traditional drugs (such as allopurinol) such as high risk of allergy and poor tolerance. Clinical demand is growing rapidly.

[0004] Patent WO2011040449 discloses a method for synthesizing dotenororil. , Starting with 2-aminobenzylthiol (compound 1), it reacts with formalin solution to generate 2,3-dihydro-1,3-benzothiazole (compound 2), which then undergoes an acylation reaction with compound 4 to generate compound 5. Compound 5 is then oxidized and demethylated to give dotenoroxetine. During the synthesis of compound 5, we discovered that a new, unknown impurity separated after the main peak with changes in reaction temperature. Through research on this new impurity, we found that it is a dimer impurity compound (formula I) formed by the dimer of compound 2 participating in the reaction. The structure of formula I is shown below:

[0005] To better control this impurity in dotenorolac, the applicant invented a method for the preparation and detection of this dimer impurity compound (Formula I), which is of great significance for research on impurities in dotenorolac. It can be used for qualitative and quantitative analysis of impurities in dotenorolac production, thereby improving the quality of dotenorolac and providing important guidance for the safe use of medication by the public. Summary of the Invention

[0006] In order to improve the quality of dotenorazole and reduce the risks of clinical use, the present invention aims to provide a dotenorazole dimer impurity compound I, its preparation method and detection method.

[0007] The first aspect of the invention provides for dotenorazine impurities (I). .

[0008] A second aspect of the present invention provides a method for preparing a dotenorazine impurity (I), comprising the following steps: , Step (4): The compound shown in Formula III reacts with the compound shown in Formula IVa under the action of a base and an organic solvent to generate dotenoroxetine impurity (I).

[0009] In some embodiments of the present invention, the base in step (4) is selected from any one or a combination of triethylamine, N-methylmorpholine, pyridine, and diisopropylethylamine.

[0010] In some embodiments of the present invention, the organic solvent in step (4) is selected from any one or a combination of multiple of dichloromethane, ethyl acetate, tetrahydrofuran, 1,4-dioxane, diethyl ether, dimethyl sulfoxide, N,N-dimethylformamide, acetone, acetonitrile, toluene, 1,2-dichloroethane, and N-methylpyrrolidone.

[0011] In some embodiments of the present invention, the temperature of the reaction in step (4) is 20~30°C.

[0012] Furthermore, the compound shown in Formula III is prepared by the following method: , Step (2): The compound shown in Formula V reacts in a base and an organic solvent to produce the compound shown in Formula II; Step (3): Dissolve the compound shown in Formula II and activated carbon in an organic solvent, and continuously blow air in during the reaction to obtain the compound shown in Formula III.

[0013] Furthermore, the base in step (2) is selected from any one or more combinations of triethylamine, diethylamine, n-propylamine, diisopropylethylamine, isopropylamine, morpholine, N-methylmorpholine, piperidine, pyridine, and piperazine; the organic solvent in step (2) is selected from any one or more combinations of tetrahydrofuran, 1,4-dioxane, dimethyl sulfoxide, N,N-dimethylformamide, acetone, and acetonitrile; the organic solvent in step (3) is selected from any one or more combinations of acetone, tetrahydrofuran, 1,4-dioxane, and acetonitrile.

[0014] Furthermore, the compound shown in formula IVa is prepared by the following method: , Step (1): The compound shown in Formula IV reacts with a chlorinating agent in dichloromethane to produce the compound shown in Formula IVa.

[0015] Furthermore, the chlorination reagent in step (1) is selected from any one or a combination of multiple of oxalyl chloride, thionyl chloride, phosphorus trichloride, and phosphorus pentachloride.

[0016] A third aspect of the invention provides the use of impurity (I) in the quality control of dotenoroxetine or its pharmaceutical compositions. , Impurity (I) serves as a reference for impurities in dotenoroxetine or its pharmaceutical compositions.

[0017] A fourth aspect of the present invention provides a method for detecting dotenorazole impurity (I) by high performance liquid chromatography. , 1) Chromatographic conditions: The column was GL Inertsil ODS-2, 250 mm × 4.6 mm × 5 μm; 0.1% phosphoric acid aqueous solution was used as mobile phase A, and acetonitrile was used as mobile phase B; the detection wavelength was 210 nm; the column temperature was 40℃; the mobile phase flow rate was 1 mL / min; the injection volume was 10 μL; gradient elution was used, and the elution gradient program was as follows: Time (min) Mobile phase A (%) Mobile phase B (%) 0 70 30 20 20 80 35 20 80 36 70 30 45 70 30 2) Preparation of the test solution: Dissolve the sample in mobile phase B; 3) Determination: Accurately measure the sample solution and inject it into the liquid chromatograph, and record the chromatogram.

[0018] Beneficial technical effects of the present invention: (1) The present invention has discovered a new impurity, which serves as a good warning for optimizing the process of this step to reduce the generation of the impurity. It is also beneficial to conduct detailed research on the removal and transfer of the impurity in the subsequent synthesis of dotenoroxetine API, so as to avoid the transfer of the impurity to the API.

[0019] (2) As an impurity reference for dotenorolac or its pharmaceutical composition, the present invention also provides a method for preparing and detecting the impurity (I). The preparation method of the present invention can quickly, easily and efficiently obtain the impurity reference, with simple process and high purity, and can provide a qualified reference for the quality control of dotenorolac. Attached Figure Description

[0020] Figure 1 : Dotenorazole impurity (I) 1 H-NMR spectrum.

[0021] Figure 2 Mass spectrum of dotenoroxetine impurity (I). Detailed Implementation

[0022] Example 1 Synthesis of Formula II

[0023] Add 50 ml of DMF to a flask, stir, and cool to 0–5 °C. Add 10.0 g (74.1 mmol) of formula V, and after it is completely dissolved, add 14.9 g (148.2 mmol) of triethylamine in fractions. Stir the reaction at this temperature for 1 h, then raise the temperature to 10–20 °C and continue the reaction for 10 h. Stop the reaction, add 100 g of ethyl acetate, stir well, and wash the organic phase three times with 50 ml of saturated brine. Distill the organic phase under reduced pressure until almost no liquid remains, giving 7.2 g of a light gray solid powder, yield 72%.

[0024] Example 2 Synthesis of Formula III

[0025] Add 200 ml of acetone to a flask, start stirring, and add 7.2 g (26.3 mmol) of Formula II and 0.7 g of activated charcoal. Continuously purge air into the reaction mixture using an air pump and heat to reflux for approximately 6 hours. Filter the reaction mixture while hot, and concentrate the filtrate under reduced pressure to a minimum volume. Perform column chromatography (silica gel, eluent: hexane:ethyl acetate = 20:1) to obtain 0.81 g of off-white columnar crystals, yield 11.2%.

[0026] Example 3 Synthesis of Formula IVa

[0027] Add 50 ml of dichloromethane and 0.1 ml of DMF to a flask and start stirring. Add 0.65 g (3.1 mmol) of formula IV. After the solid has completely dissolved, cool the reaction solution to 0–5 °C and add 0.75 g (6.2 mmol) of oxaloyl chloride in stages. After reacting for 1 h, raise the temperature of the reaction solution to 20–30 °C and continue reacting for 2 h. Concentrate the reaction solution under reduced pressure until there is almost no effluent, and dissolve it in ethyl acetate to obtain an ethyl acetate solution of formula IVa.

[0028] Example 4 Synthesis of Formula I

[0029] Add 50 ml of ethyl acetate and 0.5 g of pyridine to a flask, start stirring, and gradually cool to -15 to -5 °C. Add 0.81 g of Formula III, and stir until completely dissolved. Then, add dropwise an ethyl acetate solution of IVa obtained in Example 3. After the addition is complete, heat the reaction solution to 20-30 °C and react for 2 h. Concentrate the reaction solution to dryness, add dichloromethane and stir for 30 min, then filter. Wash the filtrate three times with water. Concentrate the filtrate until almost no liquid remains. Add 5 ml of ethyl acetate to the remaining solid, and allow it to stand at -5 to -10 °C for 24 h to crystallize. Filter to obtain 0.61 g of off-white powder, yield 43%, purity 99.2%. 1 H-NMR (600 MHz, DMSO-d6) δ:10.04 (s,1H), 7.97 (d, 2H), 7.69 (d,1H), 7.57 (d,1H), 7.37 (d, 1H), 7.26 (d,1H), 6.99 (d,1H), 6.80 (d, 1H), 6.60 (d, 1H), 6.52 (s,1H), 4.97 (s, 2H), 4.72(s,2H), 3.91 (s,3H). MS (ESI): 475.01 [MH] - .

[0030] Example 5 High-performance liquid chromatography method for the detection of dotenorazole impurity (I) (1) Chromatographic conditions: Instrument: High-performance liquid chromatograph equipped with an ultraviolet detector; Column: GL Inertsil ODS-2, 250 mm × 4.6 mm × 5 μm; Mobile phase A: 0.1% aqueous phosphoric acid solution; Mobile phase B: acetonitrile; Detection wavelength: 210 nm; Column temperature: 40 ℃; Flow rate: 1.0 mL / min; Injection volume: 10 μL; Gradient elution, the elution gradient procedure is as follows: Time (min) Mobile phase A (%) Mobile phase B (%) 0 70 30 20 20 80 35 20 80 36 70 30 45 70 30 (2) Solution preparation: Diluent: Mobile phase B; Blank solution: diluent; Test solution: Accurately weigh 4 mg of dotenorazole impurity (I) into a 20 ml volumetric flask, dilute with diluent (mobile phase B), dissolve, cool to room temperature, and then dilute to the mark with the diluent and shake well.

[0031] (3) Measurement: After the system has reached equilibrium, accurately measure 10 μL each of the blank solution and the test solution and inject them into the liquid chromatograph, then record the chromatograms.

[0032] Obviously, the above embodiments are merely illustrative examples and not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of this invention.

Claims

1. A process for preparing a polythienimide impurity (I) of doramapimod, 。 2. A process for the preparation of a polythienothiophene impurity (I) characterized by, comprising the following steps: ， Step (4): reacting a compound of formula III with a compound of formula IVa in the presence of a base and an organic solvent to form the polythienimide impurity (I) of doramapimod.

3. A process for the preparation of Polydeoxyribonucleotide impurity (I) according to claim 2, characterized by, The base in step (4) is selected from any one or a combination of more than one of triethylamine, N-methylmorpholine, pyridine, diisopropylethylamine.

4. A process for the preparation of Multinoril impurity (I) according to claim 2, characterized by, The organic solvent in step (4) is selected from any one or a combination of more than one of dichloromethane, ethyl acetate, tetrahydrofuran, 1,4-dioxane, diethyl ether, dimethyl sulfoxide, N,N-dimethylformamide, acetone, acetonitrile, toluene, 1,2-dichloroethane, N-methylpyrrolidone.

5. A process for the preparation of Multinoril impurity (I) according to claim 2, characterized by, The temperature of the reaction in step (4) is 20-30 °C.

6. A process for the preparation of Multinoril impurity (I) according to claim 2, characterized by, The compound of formula III is prepared by the following method: ， Step (2): reacting a compound of formula V in the presence of a base and an organic solvent to form a compound of formula II; Step (3): dissolving the compound of formula II with activated carbon in an organic solvent, and continuously blowing air into the system with an air pump to obtain the compound of formula III.

7. The process for preparing the polythienimide impurity (I) of doramapimod according to claim 6, wherein: The base in step (2) is selected from any one or a combination of more than one of triethylamine, diethylamine, n-propylamine, diisopropylethylamine, isopropylamine, morpholine, N-methylmorpholine, piperidine, pyridine, piperazine; The organic solvent in step (2) is selected from any one or a combination of more than one of tetrahydrofuran, 1,4-dioxane, dimethyl sulfoxide, N,N-dimethylformamide, acetone, acetonitrile; The organic solvent in step (3) is selected from any one or a combination of more than one of acetone, tetrahydrofuran, 1,4-dioxane, acetonitrile.

8. A process for the preparation of Multinoril impurity (I) according to claim 2, characterized by, The compound of formula IVa is prepared by the following method: , Step (1): reacting a compound of formula IV with a chlorinating reagent in dichloromethane to form the compound of formula IVa.

9. A process for the preparation of Multinoril impurity (I) according to claim 8, characterized by, The chlorinating reagent in step (1) is selected from any one or a combination of more than one of oxalyl chloride, dichlorosulfoxide, phosphorus trichloride, phosphorus pentachloride.

10. Use of the impurity (I) in the quality control of doramapimod or a pharmaceutical composition thereof, ， characterized in that The impurity (I) is used as a reference substance for impurities in doramapimod or a pharmaceutical composition thereof.

11. A method for detecting the polythienimide impurity (I) of doramapimod by high performance liquid chromatography, characterized in that: ， 1) Chromatographic conditions: the chromatographic column is GL Inertsil ODS-2, 250 mm x 4.6 mm x 5 μm; 0.1% phosphoric acid aqueous solution is used as the mobile phase A, and acetonitrile is used as the mobile phase B; the detection wavelength is 210 nm; the column temperature is 40 °C; the flow rate of the mobile phase is 1 mL / min; the injection volume is 10 μL; gradient elution, and the elution gradient program is as follows: 2) Preparation of the test solution: the sample is dissolved with the mobile phase B; 3) Determination: accurately take the test solution into the liquid chromatograph, and record the chromatogram.

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