Impurity compound of phenylbutyrin as well as preparation method and application of impurity compound

Abstract

The invention relates to the technical field of organic synthesis, and provides an impurity compound of phenylbutyrin as well as a preparation method and application thereof. The preparation method of the impurity compound comprises the following steps: reacting phenylbutyric acid with 1, 3-diphenoxy-2-propanol to prepare an intermediate III; replacing the intermediate III with nitrogen and hydrogen, and reacting to obtain an intermediate IV; reacting the intermediate IV with 4-oxo-4-phenylbutyric acid overnight to prepare an intermediate V; sodium borohydride is added into the intermediate V for reduction, and the impurity compound 2-((4-phenylbutyryloxy) propane-1, 3-diyl bis (4-hydroxy-4-phenylbutyrate)) of the phenylbutyrin is obtained. According to the technical scheme, the problem that the quality control related research cannot be promoted due to the lack of effective preparation means of the newly degraded impurities in the storage stage of the phenylbutyrin is solved.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, specifically to an impurity compound of phenylbutyrate, its preparation method, and its application. Background Technology

[0002] In the field of pharmaceutical research and development and manufacturing, impurity control is a core aspect of ensuring drug quality and medication safety. Drug impurities come from a wide range of sources, including starting materials, intermediates, polymers, and by-reaction products introduced during the production process, as well as degradation products generated during storage due to environmental factors. Therefore, systematic research and precise detection of various impurities in drugs have become key indicators for measuring the level of drug quality control.

[0003] Chlorobutyrate is an organic compound commonly used as a drug in the medical field, primarily for treating urea cycle disorders. Research on its impurities has attracted industry attention. However, existing literature and research findings focus more on process impurities generated during the production of chlorobutyrate. In-depth and systematic research and analysis have not yet been conducted on new degradation impurities that may arise during storage due to changes in environmental conditions. This results in a technological gap in the long-term storage quality control of chlorobutyrate and its preparations, leading to incomplete identification of new impurity risks and insufficient quality and safety assurance. Summary of the Invention

[0004] This invention proposes an impurity compound of phenylbutyrate, its preparation method and application, which solves the problem that the lack of effective preparation methods for newly degraded impurities during the storage stage of phenylbutyrate has hindered the progress of related research on its quality control.

[0005] Our team has long been dedicated to experimental research on the formation patterns of impurities in glyceryl phenylbutyrate and its preparations during storage. Extensive targeted experiments have revealed that under specific environmental conditions, glyceryl phenylbutyrate, when exposed to high temperature and light, generates an impurity with a novel chemical structure, which we have named 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)). This impurity has a significant negative impact on the quality stability of glyceryl phenylbutyrate and must be included in strict quality control.

[0006] During the storage of glyceryl phenylbutyrate and its preparations, the content of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) shows a significant increasing trend due to the influence of temperature rise and light exposure. After being stored under high temperature or light conditions for one month, the content of this impurity can reach as high as 1.417%. According to the requirements for impurity control in the "Technical Guidelines for Impurity Research of Chemical Drugs", structural identification and quality control of this impurity are necessary.

[0007] Given the critical impact of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) on the quality of phenylbutyrate glycerol, and the fact that research on this impurity is currently lacking in the industry, it is urgent to establish an effective preparation method for this impurity. This will provide the necessary material basis for subsequent development of detection methods, quality standards, and stability control studies, thereby comprehensively improving the quality control level of phenylbutyrate glycerol and its preparations and ensuring the safety of clinical use.

[0008] The technical solution of the present invention is as follows: An impurity compound of phenylbutyrate, the impurity compound having the following structural formula:

[0009] The impurity compound is 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)).

[0010] This invention also proposes a method for preparing impurity compounds of phenylbutyrate, the reaction route of which is as follows:

[0011] The target compound is 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)).

[0012] As a further technical solution, the preparation method of the intermediate III includes the following steps: dissolving phenylbutyric acid (compound I) in dichloromethane, adding 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and 4-dimethylaminopyridine, stirring, and then adding 1,3-diphenoxy-2-propanol (compound II). After reacting overnight at room temperature under an inert gas atmosphere, the intermediate III is obtained by extraction, drying, filtration, and concentration.

[0013] As a further technical solution, the molar ratio of compound I to compound II is 3~6:4.

[0014] As a further technical solution, the preparation method of intermediate IV includes the following steps: dissolving intermediate III in methanol, adding a catalyst, purging with nitrogen and hydrogen three times respectively, reacting overnight at room temperature, filtering and concentrating to obtain intermediate IV.

[0015] As a further technical solution, the catalyst is one of palladium on carbon catalyst and ruthenium on carbon catalyst, preferably palladium on carbon catalyst.

[0016] As a further technical solution, the preparation method of intermediate V includes the following steps: intermediate IV, 4-oxo-4-phenylbutyric acid, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and 4-dimethylaminopyridine are dissolved in dichloromethane, reacted overnight at room temperature under a nitrogen atmosphere, and then extracted, dried, filtered, concentrated and purified by column chromatography to obtain intermediate V.

[0017] As a further technical solution, the eluent for column chromatography purification is petroleum ether and ethyl acetate in a volume ratio of 2 to 4:1.

[0018] As a further technical solution, the preparation method of the target compound includes the following steps: dissolving intermediate V in methanol, adding sodium borohydride under a nitrogen atmosphere, reacting overnight at room temperature, extracting, drying, filtering, and concentrating to obtain the target compound, namely crude 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)), and then purifying it by high performance liquid chromatography to obtain 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)).

[0019] As a further technical solution, the gradient elution conditions during high-performance liquid chromatography purification are as follows:

[0020] Chromatographic column: octadecylsilane-bonded silica gel; mobile phase A: water; mobile phase B: acetonitrile.

[0021] As a further technical solution, the detection wavelength during the high-performance liquid chromatography purification is 210 nm.

[0022] The present invention also proposes the application of an impurity compound of phenylbutyrate or an impurity compound of phenylbutyrate prepared by the preparation method described above in the quality control of phenylbutyrate or its preparations.

[0023] The working principle and beneficial effects of this invention are as follows: The method for preparing 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) provided by this invention fills the gap in the research on newly degraded impurities during the storage stage of phenylbutyrate. It provides the necessary material basis for the development of detection methods, the formulation of quality standards and the research on stability control of this impurity, and can comprehensively improve the quality control level of phenylbutyrate and its preparations, effectively avoid the quality risk of excessive impurities, and ensure the safety of clinical medication. Attached Figure Description

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0025] Figure 1 The 1H NMR spectrum of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) in Example 1 of this invention; Figure 2 The carbon NMR spectrum of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) in Example 1 of this invention; Figure 3 This is a high-resolution mass spectrum of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) in Example 1 of the present invention. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1 A method for preparing 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) includes the following steps: S1. Dissolve (3.0 g, 18.3 mmol) phenylbutyric acid (compound I) in 20 mL of dichloromethane, add (5.85 g, 42.6 mmol) 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and (0.36 g, 4.3 mmol) 4-dimethylaminopyridine, stir for 10 min, then add (6.64 g, 24.4 mmol) 1,3-diphenoxy-2-propanol (compound II), react overnight at room temperature under nitrogen atmosphere, then extract with 30 mL of dichloromethane, dry with anhydrous sodium sulfate, filter, and concentrate to obtain intermediate III; S2. Dissolve (7.1 g, 17.1 mmol) intermediate III in 30 mL of methanol, add 1.0 g of palladium on carbon catalyst (10%), purge three times with nitrogen and hydrogen respectively, and react overnight at room temperature; filter and concentrate to obtain intermediate IV; S3. 2.5 g (10.3 mmol) of intermediate IV, 5.50 g (30.9 mmol) of 4-oxo-4-phenylbutyric acid, 5.93 g (30.9 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide, and 0.38 g (3.1 mmol) of 4-dimethylaminopyridine were dissolved in 10 mL of dichloromethane. The mixture was reacted overnight at room temperature under a nitrogen atmosphere. After extraction with 20 mL of dichloromethane, washing with water, drying with anhydrous magnesium sulfate, filtering, concentrating, and then purifying by column chromatography (eluent: petroleum ether and ethyl acetate in a 2:1 volume ratio) to obtain intermediate V. The stationary phase for column chromatography purification was silica gel, 200-300 mesh. S4. Dissolve (0.5 g, 0.9 mmol) intermediate V in 10 mL of methanol. Under a nitrogen atmosphere, add (68.1 mg, 1.8 mmol) sodium borohydride. React overnight at room temperature. After extraction with 20 mL of dichloromethane, washing with water, drying with anhydrous magnesium sulfate, filtering, and concentrating, obtain crude 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)). Purify by high performance liquid chromatography to obtain 20.8 mg of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)), with a purity of 79.3%. The gradient elution conditions for high performance liquid chromatography purification are as follows:

[0028] Column: Octadecylsilane-bonded silica gel; Mobile phase A: Water; Mobile phase B: Acetonitrile; Detection wavelength: 210 nm; The present invention examines the structure of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) obtained in Example 1. The product obtained in the embodiments of the present invention is subjected to 1 HNMR test ( Figure 1 The classification is as follows: (see Table 1)

[0029]

[0030] The product obtained in the embodiments of the present invention 13 C NMR test results ( Figure 2 The results show that all carbon atoms in the product have corresponding signals in the carbon spectrum; The products obtained in the embodiments of the present invention were subjected to HRMS testing. Figure 3 ): Positive ion mode, [M+Na] + :585.2452.

[0031] Example 2 Compared with Example 1, the only difference in Example 2 is that, in this example, in step S1, the amount of phenylbutyric acid (compound I) added is 5.0 g, 30.5 mmol; the amount of 1,3-diphenoxy-2-propanol (compound II) added is 6.64 g, 24.4 mmol; this example yields 24.3 mg of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) with a purity of 81.3%.

[0032] Example 3 Compared with Example 1, the only difference in Example 2 is that, in this example, in step S1, the amount of phenylbutyric acid (compound I) added is 6.0 g, 36.6 mmol; the amount of 1,3-diphenoxy-2-propanol (compound II) added is 6.64 g, 24.4 mmol; this example yields 23.1 mg of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) with a purity of 80.5%.

[0033] Example 4 Compared with Example 2, the only difference in Example 4 is that in this example, in step S3, the eluent is petroleum ether and ethyl acetate in a volume ratio of 3:1; this example yields 25.4 mg of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) with a purity of 81.9%.

[0034] Example 5 Compared with Example 2, the only difference in Example 5 is that in this example, in step S3, the eluent is petroleum ether and ethyl acetate in a volume ratio of 4:1; this example yields 24.0 mg of 2-((4-phenylbutyryloxy)propane-1,3-dimethylbis(4-hydroxy-4-phenylbutyrate)) with a purity of 80.8%.

[0035] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An impurity compound of glycerol phenylbutyrate, characterized by, The impurity compound has the following structural formula: The impurity compound is 2-((4-phenylbutyryloxy)propane-1,3-diyl bis(4-hydroxy-4-phenylbutyrate)).

2. A method for preparing a phenylbutyric acid glyceride impurity compound for use in the preparation of a phenylbutyric acid glyceride impurity compound as claimed in claim 1, characterized in that, The reaction route is as follows: The target compound is 2-((4-phenylbutyryloxy)propane-1,3-diyl bis(4-hydroxy-4-phenylbutyrate)).

3. The method for preparing an impurity compound of phenylbutyrate according to claim 2, characterized in that, The preparation method of the intermediate III comprises the following steps: dissolving compound I in dichloromethane, adding 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and 4-dimethylaminopyridine, stirring, then adding compound II, reacting overnight at room temperature under an inert gas atmosphere, and then extracting, drying, filtering and concentrating to obtain the intermediate III.

4. The method for preparing an impurity compound of phenylbutyrate according to claim 2, characterized in that, The preparation method of the intermediate IV comprises the following steps: dissolving the intermediate III in methanol, adding a catalyst, replacing with nitrogen and hydrogen for three times respectively, reacting overnight at room temperature, and then filtering and concentrating to obtain the intermediate IV.

5. The method for preparing an impurity compound of phenylbutyrate according to claim 4, characterized in that, The catalyst is one of a palladium-carbon catalyst and a ruthenium-carbon catalyst.

6. The method for preparing an impurity compound of phenylbutyrate according to claim 2, characterized in that, The preparation method of the intermediate V comprises the following steps: dissolving the intermediate IV, 4-oxo-4-phenylbutyric acid, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and 4-dimethylaminopyridine in dichloromethane, reacting overnight at room temperature under a nitrogen atmosphere, and then extracting, drying, filtering, concentrating and purifying by column chromatography to obtain the intermediate V. The eluent for the column chromatography purification is petroleum ether and ethyl acetate in a volume ratio of 2-4:

1.

7. The method for preparing an impurity compound of phenylbutyrate according to claim 6, characterized in that, The preparation method of the target compound comprises the following steps: dissolving the intermediate V in methanol, adding sodium borohydride under the protection of a nitrogen atmosphere, reacting overnight at room temperature, then extracting and drying, and then filtering, concentrating and purifying by high performance liquid chromatography to obtain the target compound, i.e., 2-((4-phenylbutyryloxy)propane-1,3-diyl bis(4-hydroxy-4-phenylbutyrate)) crude product.

8. The method for preparing an impurity compound of phenylbutyrate according to claim 2, characterized in that, The gradient elution conditions for the high performance liquid chromatography purification are as follows:

9. The method for preparing an impurity compound of phenylbutyrate according to claim 8, characterized in that, The chromatographic column is octadecylsilane bonded silica gel; the mobile phase A is water; and the mobile phase B is acetonitrile.

10. The impurity compound of phenylbutyrates according to claim 1 or prepared by the preparation method according to any one of claims 2-9, in the quality control of phenylbutyrates or preparations thereof. ​

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