Method for Separating Cariprazine Hydrochloride and Its Cis-Isomer Impurity by Liquid Chromatography

Abstract

The present disclosure relates to the field of pharmaceutical analytical chemistry, and provides a method for separating cariprazine hydrochloride and its cis-isomer impurity by liquid chromatography. The liquid chromatography is normal-phase liquid chromatography. The chromatographic column used in the normal-phase liquid chromatography is a chiral chromatographic column. The mobile phase used is a mixed solution of an alkane solvent, an alcohol solvent and a modifier. Among them, the modifier includes one of triethylamine and diethylamine. The method provided by the present disclosure can achieve complete separation of cariprazine hydrochloride and its cis-isomer impurity, thereby providing data support for the screening of the preparation process and quality control of cariprazine hydrochloride, and is of great significance in terms of the quality controllability and safety of the preparation products of cariprazine hydrochloride.

Description

Technical Field

[0001] The present disclosure relates to the technical field of pharmaceutical analytical chemistry, for example, to a method for separating cariprazine hydrochloride and its cis-isomer impurity by liquid chromatography. Background Art

[0002] Cariprazine hydrochloride, chemically named trans-N-4-{2-[4-(2,3-dichlorophenyl)-1-piperazinyl]ethyl}cyclohexyl-N’,N’-dimethylurea hydrochloride (its structural formula is shown in Formula I), is an atypical antipsychotic drug, applicable to the treatment of adult schizophrenia, the treatment related to acute mania or mania, and the treatment of depressive episodes related to adult bipolar disorder type I (i.e., bipolar depression).

[0003]

[0004] There are cis- and trans-structures on the cyclohexyl group in the structure of cariprazine hydrochloride. However, in the synthesis route of cariprazine hydrochloride (for example, CN110872262A, CN105330616B or CN102256955B) or the synthesis route of its key intermediate (for example, CN102224130B), the cis-structure on the cyclohexyl group may be introduced through starting materials or intermediates, thus generating the cis-isomer impurity of cariprazine hydrochloride during the synthesis process (its structural formula is shown in Formula II).

[0005]

[0006] It can be seen that establishing a method for separating cariprazine hydrochloride and its cis-isomer impurity is of great significance for the screening and quality control of the preparation process of cariprazine hydrochloride. However, at present, the research on the separation method of cariprazine hydrochloride and its cis-isomer impurity is seriously lacking, which makes it still difficult to improve the quality controllability and safety of the preparation products of cariprazine hydrochloride.

[0007] In summary, there is an urgent need for a method that can achieve the complete separation of cariprazine hydrochloride and its cis-isomer impurity. Summary of the Invention

[0008] The purpose of the present disclosure is to overcome the deficiencies in the prior art and provide a method for separating cariprazine hydrochloride and its cis-isomer impurity by liquid chromatography to achieve the complete separation of cariprazine hydrochloride and its cis-isomer impurity.

[0009] The purpose of the present disclosure is achieved by the following technical solutions:

[0010] On the one hand, a method for separating cariprazine hydrochloride and its cis - isomer impurity by liquid chromatography is provided. The liquid chromatography is normal - phase liquid chromatography, and the chromatographic conditions of the normal - phase liquid chromatography include: chromatographic column: chiral chromatographic column; mobile phase: a mixed solution of an alkane solvent, an alcohol solvent, and a modifier; wherein, the modifier includes one of triethylamine and diethylamine.

[0011] In this regard, it should be noted that the molecular formula of cariprazine hydrochloride is C 21 H 33 Cl3N4O, with a molecular weight of 463.87, and its structural formula is shown as Formula I.

[0012]

[0013] The molecular formula of the cis - isomer impurity of cariprazine hydrochloride is C 21 H 32 Cl2N4O, with a molecular weight of 427.41, and its structural formula is shown as Formula II.

[0014]

[0015] Therefore, it should be understood that cariprazine hydrochloride and the cis - isomer impurity belong to stereoisomers.

[0016] It is worth noting that the method provided by the present disclosure can improve the selectivity for cariprazine hydrochloride and the cis - isomer impurity by separating cariprazine hydrochloride and the cis - isomer impurity in a normal - phase mode using the chiral chromatographic column. On this basis, by adding the modifier to the mobile phase, the peak shape and resolution of the chromatographic peaks can be improved, and finally, the complete separation of cariprazine hydrochloride and the cis - isomer impurity is achieved.

[0017] In some embodiments, the alkane solvent includes n - hexane.

[0018] In some embodiments, the alcohol solvent includes one of isopropanol, ethanol, and methanol.

[0019] In some examples, the alcohol solvent is ethanol.

[0020] In some examples, the modifier is diethylamine.

[0021] Exemplarily, the mobile phase is a mixed solution of n - hexane, ethanol, and diethylamine.

[0022] In the above technical solution, by further defining the composition components of the mobile phase, the peak shape and resolution of the chromatographic peaks can be further improved.

[0023] In some embodiments, the volume of the modifier is 0.1% to 1% of the total volume of both the alkane solvent and the alcohol solvent.

[0024] In some examples, the volume of the modifier is 0.2% of the total volume of both the alkane solvent and the alcohol solvent.

[0025] In the above technical solution, by further limiting the addition amount of the modifier, the peak shape and resolution of the chromatographic peak can be further improved.

[0026] In some embodiments, the volume ratio of the alkane solvent to the alcohol solvent is 98:2 to 70:30.

[0027] In some examples, the volume ratio of the alkane solvent to the alcohol solvent is 85:15.

[0028] In the above technical solution, by limiting the volume ratio of the alkane solvent to the alcohol solvent, the resolution of the cariprazine hydrochloride and the cis isomer impurity and the required elution time can be better controlled.

[0029] In some embodiments, the flow rate of the mobile phase is 0.5 to 1.5 mL / min.

[0030] In some examples, the flow rate of the mobile phase is 1.0 mL / min.

[0031] In some embodiments, the column temperature of the chiral chromatographic column is 25 to 50 °C.

[0032] In some examples, the column temperature of the chiral chromatographic column is 40 °C.

[0033] In some embodiments, the chiral chromatographic column includes one of Chiral INA, Lux Cellulose-1, and ODS-SP.

[0034] In some examples, the chiral chromatographic column is Chiral INA.

[0035] In some embodiments, the chromatographic conditions of the normal-phase liquid chromatography further include: detection wavelength: 200 to 280 nm; injection volume: 10 to 50 μL; elution program: isocratic elution.

[0036] In some examples, the detection wavelength is 230 nm.

[0037] In some examples, the injection volume is 10 μL.

[0038] In some embodiments, the time of the isocratic elution is 10 to 60 min.

[0039] In some examples, the time for isocratic elution is 10 min.

[0040] In some embodiments, the method includes: separately detecting a blank solution, a system suitability solution, and a test solution by using the normal-phase liquid chromatography method, and recording a chromatogram. On this basis, exemplarily, the method further includes: after recording the chromatogram, calculating the content of the cis isomer impurity in the test solution by the peak area normalization method.

[0041] Among them, the blank solution is the same as the mobile phase.

[0042] The method for preparing the system suitability solution includes: taking a cariprazine hydrochloride reference substance and a cis isomer impurity reference substance, adding a first solvent to dissolve them to obtain the system suitability solution; among them, the first solvent is the same as the mobile phase. On this basis, exemplarily, in the system suitability solution, the concentration of the cariprazine hydrochloride reference substance is 2 g / L, and the concentration of the cis isomer impurity reference substance is 0.02 g / L.

[0043] The method for preparing the test solution includes: taking a sample to be tested, adding a second solvent to dissolve it to obtain the test solution; among them, the second solvent is the same as the mobile phase. On this basis, exemplarily, in the test solution, the concentration of the sample to be tested is 0.5 - 3 g / L, for example, 2 g / L.

[0044] The beneficial effects of the present disclosure are:

[0045] 1. A method for separating cariprazine hydrochloride and its cis isomer impurity by using liquid chromatography provided by the present disclosure can improve the selectivity for cariprazine hydrochloride and its cis isomer impurity by separating cariprazine hydrochloride and its cis isomer impurity in a normal-phase mode by using a chiral chromatographic column.

[0046] 2. A method for separating cariprazine hydrochloride and its cis isomer impurity by using liquid chromatography provided by the present disclosure can improve the peak shape and resolution of chromatographic peaks by adding a modifier to the mobile phase.

[0047] 3. A method for separating cariprazine hydrochloride and its cis isomer impurity by using liquid chromatography provided by the present disclosure can achieve complete separation of cariprazine hydrochloride and its cis isomer impurity.

[0048] 4. A method for separating cariprazine hydrochloride and its cis - isomer impurity by liquid chromatography provided by the present disclosure can provide data support for the screening of the preparation process and quality control of cariprazine hydrochloride, and is of great significance in terms of the quality controllability and safety of the pharmaceutical products of cariprazine hydrochloride. Description of the Drawings

[0049] To more clearly illustrate the technical solutions in the present disclosure, the drawings required for use in some embodiments of the present disclosure will be briefly introduced below. Obviously, the drawings in the following description are only the drawings of some embodiments of the present disclosure, and those of ordinary skill in the art can also obtain other drawings based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams and are not limitations on the actual processes of the methods involved in the embodiments of the present disclosure.

[0050] Figure 1 It is the liquid chromatogram of the blank solution in Example 1 of the present disclosure;

[0051] Figure 2 It is the liquid chromatogram of the system suitability solution in Example 1 of the present disclosure;

[0052] Figure 3 It is the liquid chromatogram of the test solution in Example 1 of the present disclosure;

[0053] Figure 4 It is the liquid chromatogram of the blank solution in Example 2 of the present disclosure;

[0054] Figure 5 It is the liquid chromatogram of the system suitability solution in Example 2 of the present disclosure;

[0055] Figure 6 It is the liquid chromatogram of the test solution in Example 2 of the present disclosure;

[0056] Figure 7 It is the liquid chromatogram of the blank solution in Example 3 of the present disclosure;

[0057] Figure 8 It is the liquid chromatogram of the system suitability solution in Example 3 of the present disclosure;

[0058] Figure 9 It is the liquid chromatogram of the test solution in Example 3 of the present disclosure;

[0059] Figure 10 It is the liquid chromatogram of the blank solution in Example 4 of the present disclosure;

[0060] Figure 11 It is the liquid chromatogram of the system suitability solution in Example 4 of the present disclosure;

[0061] Figure 12The liquid chromatogram of the test solution in Example 4 of the present disclosure;

[0062] Figure 13 The liquid chromatogram of the blank solution in Example 5 of the present disclosure;

[0063] Figure 14 The liquid chromatogram of the system suitability solution in Example 5 of the present disclosure;

[0064] Figure 15 The liquid chromatogram of the test solution in Example 5 of the present disclosure;

[0065] Figure 16 The liquid chromatogram of the blank solution in Example 6 of the present disclosure;

[0066] Figure 17 The liquid chromatogram of the system suitability solution in Example 6 of the present disclosure;

[0067] Figure 18 The liquid chromatogram of the test solution in Example 6 of the present disclosure;

[0068] Figure 19 The liquid chromatogram of the blank solution in Comparative Example 1 of the present disclosure;

[0069] Figure 20 The liquid chromatogram of the system suitability solution in Comparative Example 1 of the present disclosure;

[0070] Figure 21 The liquid chromatogram of the test solution in Comparative Example 1 of the present disclosure;

[0071] Figure 22 The liquid chromatogram of the blank solution in Comparative Example 2 of the present disclosure;

[0072] Figure 23 The liquid chromatogram of the system suitability solution in Comparative Example 2 of the present disclosure;

[0073] Figure 24 The liquid chromatogram of the test solution in Comparative Example 2 of the present disclosure. Detailed implementation manners

[0074] Next, the technical solutions in some embodiments of the present disclosure will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present disclosure.

[0075] Hereinafter, the terms "first", "second", etc. are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features.

[0076] When describing some embodiments, the expression "A and / or B" may be used. It is readily understood that "A and / or B" includes the following three combinations: only A, only B, and the combination of A and B.

[0077] When describing some embodiments, the expressions "at least one of A, B, and C" and "at least one of A, B, or C" may be used. Both have the same meaning and include the following combinations of A, B, and C: only A, only B, only C, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B, and C.

[0078] It should be noted that the sources of the cariprazine hydrochloride reference substance, cis-isomer impurity reference substance, and the sample to be tested used in the embodiments of the present disclosure are as follows:

[0079] The cariprazine hydrochloride reference substance is from Sichuan Aobang Good Pharmaceutical Co., Ltd., with the batch number T220201-R and the content of 99.67%;

[0080] The cis-isomer impurity reference substance is from Sichuan Aobang Good Pharmaceutical Co., Ltd., with the batch number 022-Z05-211126-01-02-R and the content of 98.47%;

[0081] The sample to be tested is from Chengdu Aobang Pharmaceutical Co., Ltd., with the batch number T220201.

[0082] In addition, the instruments and other reagents used in the embodiments of the present disclosure can be purchased from the market.

[0083] Example 1

[0084] 1. Chromatographic conditions

[0085] Chromatographic column: Chiral INA 250×4.6 mm, 5 μm;

[0086] Detection wavelength: 230 nm;

[0087] Flow rate: 1.0 mL / min;

[0088] Column temperature: 40 °C;

[0089] Mobile phase: n-hexane - ethanol - diethylamine (85:15:0.2);

[0090] Injection volume: 10 μL;

[0091] Elution procedure: Isocratic elution for 10 min.

[0092] 2. Preparation of blank solution:

[0093] Mix n - hexane, ethanol, and diethylamine in a volume ratio of 85:15:0.2 to obtain it; that is, the blank solution is the same as the mobile phase.

[0094] 3. Preparation of test solution:

[0095] Take an appropriate amount of the sample to be tested, add the first solvent to dissolve and dilute to prepare a solution with a concentration of 2 g / L; among them, the first solvent is the same as the above - mentioned mobile phase.

[0096] 4. Preparation of system suitability solution:

[0097] Take appropriate amounts of cariprazine hydrochloride reference substance and cis - isomer impurity reference substance, add the second solvent to dissolve and dilute to prepare a mixed solution containing 2 g / L of cariprazine hydrochloride and 0.02 g / L of cis - isomer impurity; among them, the second solvent is the same as the above - mentioned mobile phase.

[0098] 5. Separation and determination of cariprazine hydrochloride and its cis - isomer impurity

[0099] Inject the above - mentioned blank solution, the above - mentioned test solution, and the above - mentioned system suitability solution into the above - mentioned liquid chromatograph respectively according to the above - mentioned chromatographic conditions, and record the chromatogram, as Figures 1 - 3 shown.

[0100] On this basis, the data results of Example 1 are shown in Table 1:

[0101] Table 1 Data results of Example 1

[0102] Name Retention Time (min) Resolution Theoretical Plate Number Tailing Factor Cis-Isomer Impurity 5.236 —— 9276 1.2 Cariprazine Hydrochloride 6.243 4.0 7538 1.4

[0103] It can be seen that under the above - mentioned chromatographic conditions, the solvent peak does not interfere with the detection of the cis - isomer impurity, and the resolution between the cis - isomer impurity peak and the cariprazine hydrochloride peak is 4.0.

[0104] It should be noted that after recording the chromatogram, the content of the cis - isomer impurity in the test solution can be further calculated by the peak area normalization method. The method for calculating the content of the cis - isomer impurity in the test solution by the peak area normalization method can be adaptively selected with reference to relevant technologies, and this disclosure's embodiments do not limit this.

[0105] Example 2

[0106] 1. Chromatographic conditions

[0107] Chromatographic column: Chiral INA 250×4.6 mm, 5 μm;

[0108] Detection wavelength: 230 nm;

[0109] Flow rate: 0.9 mL / min;

[0110] Column temperature: 35 °C;

[0111] Mobile phase: n-hexane - ethanol - diethylamine (83:17:0.2);

[0112] Injection volume: 10 μL;

[0113] Elution program: Isocratic elution for 10 min.

[0114] 2. Preparation of blank solution:

[0115] Mix n-hexane, ethanol, and diethylamine according to the volume ratio of 83:17:0.2 to obtain it; that is, the blank solution is the same as the mobile phase.

[0116] 3. Preparation of test solution:

[0117] Take an appropriate amount of the sample to be tested, add the first solvent to dissolve and dilute to make a solution of 2 g / L; among them, the first solvent is the same as the above mobile phase.

[0118] 4. Preparation of system suitability solution:

[0119] Take appropriate amounts of cariprazine hydrochloride reference substance and cis-isomer impurity reference substance, add the second solvent to dissolve and dilute to make a mixed solution containing 2 g / L of cariprazine hydrochloride and 0.02 g / L of cis-isomer impurity; among them, the second solvent is the same as the above mobile phase.

[0120] 5. Separation and determination of cariprazine hydrochloride and its cis-isomer impurity

[0121] Inject the above blank solution, the above test solution, and the above system suitability solution into the above liquid chromatograph respectively according to the above chromatographic conditions, and record the chromatogram, as Figures 4 - 6 shown.

[0122] On this basis, the data results of Example 2 are shown in Table 2:

[0123] Table 2 Data results of Example 2

[0124] Name Retention Time (min) Resolution Theoretical Plate Number Tailing Factor Cis-Isomer Impurity 5.186 —— 12977 1.1 Cariprazine Hydrochloride 6.025 4.0 10691 1.2

[0125] It can be seen that under the above chromatographic conditions, the solvent peak does not interfere with the detection of the cis-isomer impurity, and the resolution between the cis-isomer impurity peak and the cariprazine hydrochloride peak is 4.0.

[0126] It should be noted that after recording the chromatogram, the content of the cis-isomer impurity in the test solution can be further calculated by the peak area normalization method. The method for calculating the content of the cis-isomer impurity in the test solution by the peak area normalization method can be adaptively selected with reference to relevant technologies, and the embodiments of the present disclosure do not limit this.

[0127] Example 3

[0128] 1. Chromatographic conditions

[0129] Chromatographic column: Chiral INA 250×4.6 mm, 5 μm;

[0130] Detection wavelength: 230 nm;

[0131] Flow rate: 1.1 mL / min;

[0132] Column temperature: 45 °C;

[0133] Mobile phase: n-hexane - ethanol - diethylamine (87:13:0.2);

[0134] Injection volume: 10 μL;

[0135] Elution program: Isocratic elution for 12 min.

[0136] 2. Preparation of blank solution:

[0137] Mix n-hexane, ethanol, and diethylamine in a volume ratio of 83:17:0.2 to obtain it; that is, the blank solution is the same as the mobile phase.

[0138] 3. Preparation of test solution:

[0139] Take an appropriate amount of the sample to be tested, add the first solvent to dissolve and dilute to make a solution of 2 g / L; wherein, the first solvent is the same as the above mobile phase.

[0140] 4. Preparation of system suitability solution:

[0141] Take appropriate amounts of the cariprazine hydrochloride reference substance and the cis-isomer impurity reference substance, add the second solvent to dissolve and dilute to make a mixed solution containing 2 g / L of cariprazine hydrochloride and 0.02 g / L of cis-isomer impurity; wherein, the second solvent is the same as the above mobile phase.

[0142] 5. Separation and determination of cariprazine hydrochloride and its cis-isomer impurity

[0143] Inject the above blank solution, the above test solution, and the above system suitability solution into the above liquid chromatograph respectively according to the above chromatographic conditions, and record the chromatogram, as Figures 7 - 9 shown.

[0144] On this basis, the data results of Example 3 are shown in Table 3:

[0145] Table 3 Data Results of Example 3

[0146] Name Retention Time (min) Resolution Theoretical Plate Number Tailing Factor Cis-Isomer Impurity 6.653 —— 10089 1.2 Cariprazine Hydrochloride 7.916 4.0 7568 1.6

[0147] It can be seen therefrom that under the above chromatographic conditions, the solvent peak does not interfere with the detection of the cis isomer impurity, and the resolution between the cis isomer impurity peak and the cariprazine hydrochloride peak is 4.0.

[0148] It should be noted that after recording the chromatogram, the content of the cis isomer impurity in the test solution can be further calculated by the peak area normalization method. The method for calculating the content of the cis isomer impurity in the test solution by the peak area normalization method can be adaptively selected with reference to relevant technologies, and the embodiments of the present disclosure do not limit this.

[0149] Example 4

[0150] 1. Chromatographic Conditions

[0151] Chromatographic column: Chiral INA 250×4.6 mm, 5 μm;

[0152] Detection wavelength: 230 nm;

[0153] Flow rate: 1.0 mL / min;

[0154] Column temperature: 40 °C;

[0155] Mobile phase: n-hexane - ethanol - triethylamine (85:15:0.2);

[0156] Injection volume: 10 μL;

[0157] Elution program: Isocratic elution for 10 min.

[0158] 2. Preparation of Blank Solution:

[0159] Mix n-hexane, ethanol, and triethylamine in a volume ratio of 85:15:0.2 to obtain it; that is, the blank solution is the same as the mobile phase.

[0160] 3. Preparation of Test Solution:

[0161] Take an appropriate amount of the sample to be tested, add the first solvent to dissolve and dilute to make a solution of 2 g / L; wherein, the first solvent is the same as the above mobile phase.

[0162] 4. Preparation of System Suitability Solution:

[0163] Weigh appropriate amounts of cariprazine hydrochloride reference substance and cis-isomer impurity reference substance, dissolve and dilute them with the second solvent to prepare a mixed solution containing 2 g / L of cariprazine hydrochloride and 0.02 g / L of cis-isomer impurity; among them, the second solvent is the same as the above-mentioned mobile phase.

[0164] 5. Separation and determination of cariprazine hydrochloride and its cis-isomer impurity

[0165] Inject the above blank solution, the above test solution, and the above system suitability solution into the above liquid chromatograph respectively according to the above chromatographic conditions, and record the chromatogram, as Figures 10 - 12 shown.

[0166] On this basis, the data results of Example 4 are shown in Table 4:

[0167] Table 4 Data results of Example 4

[0168] Name Retention Time (min) Resolution Theoretical Plate Number Tailing Factor Cis-Isomer Impurity 3.261 — 4511 1.2 Cariprazine Hydrochloride 3.755 2.5 4864 1.2

[0169] It can be seen therefrom that under the above chromatographic conditions, the solvent peak does not interfere with the detection of the cis-isomer impurity, and the resolution between the cis-isomer impurity peak and the cariprazine hydrochloride peak is 2.5.

[0170] It should be noted that after recording the chromatogram, the content of the cis-isomer impurity in the test solution can be further calculated by the peak area normalization method. The method for calculating the content of the cis-isomer impurity in the test solution by the peak area normalization method can be adaptively selected with reference to related technologies, and the embodiments of the present disclosure do not limit this.

[0171] Example 5

[0172] 1. Chromatographic conditions

[0173] Chromatographic column: Chiral INA 250×4.6 mm, 5 μm;

[0174] Detection wavelength: 210 nm;

[0175] Flow rate: 1.0 mL / min;

[0176] Column temperature: 40 °C;

[0177] Mobile phase: n-hexane - methanol - diethylamine (98:2:1);

[0178] Injection volume: 10 μL;

[0179] Elution program: Isocratic elution for 60 min.

[0180] 2. Preparation of blank solution:

[0181] It is obtained by mixing n - hexane, methanol and diethylamine in a volume ratio of 98:2:1; that is, the blank solution is the same as the mobile phase.

[0182] 3. Preparation of test solution:

[0183] Take an appropriate amount of the sample to be tested, add the first solvent to dissolve and dilute it to make a solution with a concentration of 2 g / L; among them, the first solvent is the same as the above - mentioned mobile phase.

[0184] 4. Preparation of system suitability solution:

[0185] Take appropriate amounts of cariprazine hydrochloride reference substance and cis - isomer impurity reference substance, add the second solvent to dissolve and dilute to make a mixed solution containing 2 g / L of cariprazine hydrochloride and 0.02 g / L of cis - isomer impurity; among them, the second solvent is the same as the above - mentioned mobile phase.

[0186] 5. Separation and determination of cariprazine hydrochloride and its cis - isomer impurity

[0187] Inject the above - mentioned blank solution, the above - mentioned test solution and the above - mentioned system suitability solution into the above - mentioned liquid chromatograph respectively according to the above - mentioned chromatographic conditions, and record the chromatogram, as Figures 13 - 15 shown.

[0188] On this basis, the data results of Example 5 are shown in Table 5:

[0189] Table 5 Data results of Example 5

[0190] Name Retention Time (min) Resolution Theoretical Plate Number Tailing Factor Cis-Isomer Impurity 34.215 — 1587 1.2 Cariprazine Hydrochloride 40.507 3.2 1841 2.5

[0191] It can be seen that under the above - mentioned chromatographic conditions, the solvent peak does not interfere with the detection of the cis - isomer impurity, and the resolution between the cis - isomer impurity peak and the cariprazine hydrochloride peak is 3.2.

[0192] It should be noted that after recording the chromatogram, the content of the cis - isomer impurity in the test solution can be further calculated by the peak area normalization method. The method for calculating the content of the cis - isomer impurity in the test solution by the peak area normalization method can be adaptively selected with reference to relevant technologies, and the embodiments of the present disclosure do not limit this.

[0193] Example 6

[0194] 1. Chromatographic conditions

[0195] Chromatographic column: Chiral INA 250×4.6 mm, 5 μm;

[0196] Detection wavelength: 250 nm;

[0197] Flow rate: 1.0 mL / min;

[0198] Column temperature: 35 °C;

[0199] Mobile phase: n - hexane - isopropanol - diethylamine (70:30:0.1);

[0200] Injection volume: 10 μL;

[0201] Elution program: Isocratic elution for 20 min.

[0202] 2. Preparation of blank solution:

[0203] Mix n - hexane, isopropanol and diethylamine according to the volume ratio of 70:30:0.1, and that is it; namely, the blank solution is the same as the mobile phase.

[0204] 3. Preparation of test solution:

[0205] Take an appropriate amount of the sample to be tested, add the first solvent to dissolve and dilute to make a solution of 2 g / L; wherein, the first solvent is the same as the above - mentioned mobile phase.

[0206] 4. Preparation of system suitability solution:

[0207] Take appropriate amounts of cariprazine hydrochloride reference substance and cis - isomer impurity reference substance, add the second solvent to dissolve and dilute to make a mixed solution containing 2 g / L of cariprazine hydrochloride and 0.02 g / L of cis - isomer impurity; wherein, the second solvent is the same as the above - mentioned mobile phase.

[0208] 5. Separation and determination of cariprazine hydrochloride and its cis - isomer impurity

[0209] Inject the above - mentioned blank solution, the above - mentioned test solution and the above - mentioned system suitability solution into the above - mentioned liquid chromatograph respectively according to the above - mentioned chromatographic conditions, and record the chromatogram, as Figures 16 - 18 shown.

[0210] On this basis, the data results of Example 6 are shown in Table 6:

[0211] Table 6 Data results of Example 6

[0212] Name Retention Time (min) Resolution Theoretical Plate Number Tailing Factor Cis-Isomer Impurity 2.811 — 4876 1.0 Cariprazine Hydrochloride 3.094 1.6 5186 1.0

[0213] It can be seen therefrom that under the above - mentioned chromatographic conditions, the solvent peak does not interfere with the detection of the cis - isomer impurity, and the resolution between the cis - isomer impurity peak and the cariprazine hydrochloride peak is 1.6.

[0214] It should be noted that after recording the chromatogram, the content of the cis-isomer impurity in the test solution can be further calculated by the peak area normalization method. The method for calculating the content of the cis-isomer impurity in the test solution by the peak area normalization method can be adaptively selected with reference to relevant technologies, and the embodiments of the present disclosure do not limit this.

[0215] It should be understood that for the separation of cariprazine hydrochloride and its cis-isomer impurity, as long as the resolution between the cis-isomer impurity peak and the cariprazine hydrochloride peak can meet the requirement of being greater than 1.5 under the corresponding chromatographic conditions, it can be regarded that the current chromatographic conditions can achieve the complete separation of cariprazine hydrochloride and its cis-isomer impurity; on this basis, the greater the resolution between the two peaks, the better the separation effect.

[0216] Therefore, the methods provided in Examples 1-6 can achieve the complete separation of cariprazine hydrochloride and its cis-isomer impurity.

[0217] Control Example 1

[0218] Control Example 1 was compared with Examples 1 and 4. The difference between Control Example 1 and Examples 1 and 4 is that the mobile phase is n-hexane-ethanol-trifluoroacetic acid (85:15:0.2), that is, trifluoroacetic acid is used as the modifier; other conditions such as the remaining chromatographic conditions and method steps are the same as those in Examples 1 and 4 (in this control example compared with Examples 1 and 4, the modifier is replaced with trifluoroacetic acid to prove that the method of the present disclosure has a better effect).

[0219] The results are as Figures 19 - 21 shown. Under the above chromatographic conditions, the peak shapes of the cis-isomer impurity peak and the cariprazine hydrochloride peak are poor, and the separation effect between the peaks is poor.

[0220] Control Example 2

[0221] Control Example 2 was compared with Examples 1 and 4. The difference between Control Example 2 and Examples 1 and 4 is that the mobile phase is n-hexane-ethanol (85:15), that is, no modifier is added; other conditions such as the remaining chromatographic conditions and method steps are the same as those in Examples 1 and 4 (in this control example compared with Examples 1 and 4, no modifier is added to prove that the method of the present disclosure has a better effect).

[0222] The results are as Figures 22 - 24 shown. Under the above chromatographic conditions, the peak shapes of the cis-isomer impurity peak and the cariprazine hydrochloride peak are poor, and the separation effect between the peaks is poor.

[0223] Experimental Example 1

[0224] To verify the effectiveness of the method provided by the present disclosure, the detection limit, quantification limit, linearity, accuracy, and precision of the above method were also verified.

[0225] 1. Verification of Detection Limit, Quantification Limit, and Linearity

[0226] Preparation of linear stock solution: Appropriate amounts of cariprazine hydrochloride reference substance and cis - isomer impurity reference substance were accurately weighed, quantitatively diluted with a solvent (the same as the mobile phase in Example 1) to prepare a mixed solution containing 20 μg of cariprazine hydrochloride and cis - isomer impurity in each 1 mL.

[0227] On this basis, the linear stock solution was serially diluted to different concentrations, and solutions of each concentration were taken in the order from low to high concentration and injected for analysis under the chromatographic conditions of Example 1. The results are shown in Table 7.

[0228] Table 7 Verification Results of Detection Limit, Quantification Limit, and Linearity

[0229]

[0230]

[0231] 2. Verification of Accuracy

[0232] Spiked recovery solution: Appropriate amounts of the test samples were taken, appropriate amounts of the linear stock solution were added, and diluted with a solvent (the same as the mobile phase in Example 1) to prepare solutions with three different mass concentrations of 30%, 100%, and 150%, and 3 parallel preparations were made.

[0233] Each solution was injected for analysis under the chromatographic conditions of Example 1. The results are shown in Table 8.

[0234] Table 8 Verification Results of Accuracy

[0235]

[0236] 3. Precision

[0237] Preparation of test solution: Appropriate amounts of the test samples were accurately weighed, appropriate amounts of the linear stock solution were added, and diluted with a solvent (the same as the mobile phase in Example 1) to prepare a spiked solution with a mass concentration of 100%, and 6 parallel preparations were made.

[0238] Each solution was injected for analysis under the chromatographic conditions of Example 1. The results are shown in Table 9.

[0239] Table 9 Verification Results of Precision

[0240]

[0241] Therefore, a method for separating cariprazine hydrochloride and its cis-isomer impurity by liquid chromatography according to the present disclosure can achieve complete separation of cariprazine hydrochloride and its cis-isomer impurity, thereby providing data support for the screening of the preparation process and quality control of cariprazine hydrochloride, and is of great significance in terms of the quality controllability and safety of the pharmaceutical products of cariprazine hydrochloride.

[0242] The above are only the preferred embodiments of the present disclosure. It should be understood that the present disclosure is not limited to the forms disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept described herein through the above teachings or the techniques or knowledge in the relevant field. Any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present disclosure shall fall within the protection scope of the appended claims of the present disclosure.

Claims

1. A method for separating cariprazine hydrochloride and its cis-isomer impurities by liquid chromatography, characterized in that, The liquid chromatography method is normal-phase liquid chromatography, and the chromatographic conditions of the normal-phase liquid chromatography are as follows: Chromatographic column: chiral chromatographic column; Mobile phase: a mixed solution of an alkane solvent, an alcohol solvent, and a modifier; Among them, the alcohol solvent is one of isopropanol, ethanol, and methanol; The modifier is one of triethylamine and diethylamine; The alkane solvent is n-hexane; The volume of the modifier is 0.1% to 1% of the total volume of the alkane solvent and the alcohol solvent; The volume ratio of the alkane solvent to the alcohol solvent is 98:2 to 70:

30.

2. The method according to claim 1, wherein The flow rate of the mobile phase is 0.5 to 1.5 mL / min.

3. The method according to claim 1, characterized in that The column temperature of the chiral chromatographic column is 25 to 50 °C.

4. The method according to claim 1, wherein The chiral chromatographic column is one of Chiral INA, LuxCellulose-1, and ODS-SP.

5. The method according to claim 1, wherein The chromatographic conditions of the normal-phase liquid chromatography further include: Detection wavelength: 200 to 280 nm; Injection volume: 10 to 50 μL; Elution program: isocratic elution.

6. The method according to claim 5, wherein The time of the isocratic elution is 10 to 60 min.

7. The method according to any one of claims 1 to 6, characterized in that The method includes: Detecting the blank solution, the system suitability solution, and the test solution respectively by using the normal-phase liquid chromatography method, and recording the chromatogram; Among them, the blank solution is the same as the mobile phase; The method for preparing the system suitability solution includes: Taking a cariprazine hydrochloride reference substance and a cis-isomer impurity reference substance, adding a first solvent to dissolve them to obtain the system suitability solution; among them, the first solvent is the same as the mobile phase; The method for preparing the test solution includes: Taking a sample to be tested, adding a second solvent to dissolve it to obtain the test solution; among them, the second solvent is the same as the mobile phase.

Images