A method for detecting related substances of dexzopiclone intermediate YZ1

Abstract

The present invention relates to the technical field of chemical analysis, and discloses a method for detecting related substances of a dexzopiclone intermediate YZ1, wherein the method comprises the following steps: S1. preparing a test solution and an impurity positioning solution respectively for standby use; S2. accurately measuring equal amounts of the test solution and the impurity positioning solution, respectively injecting them into a high performance liquid chromatograph, using mobile phase A and mobile phase B for separation and analysis in a gradient elution mode, and recording a chromatogram; wherein the chromatographic conditions are: using octadecylsilane bonded silica gel as a filler; using a perchloric acid trifluoroacetic acid aqueous solution as mobile phase A, and acetonitrile as mobile phase B; and in the perchloric acid trifluoroacetic acid aqueous solution, the volume ratio of perchloric acid, trifluoroacetic acid and water is: 0.1-0.5:1:1000. The present invention adopts high performance liquid chromatography, and by analyzing the contents of effective ingredients and impurities in the dexzopiclone intermediate, the purity of the dexzopiclone intermediate can be monitored, the quality can be ensured, and the production process can be evaluated.

Description

Technical Field

[0001] The invention relates to the technical field of chemical analysis, and in particular to a method for detecting related substances of a dexzopiclone intermediate YZ1. Background Art

[0002] Dexzopiclone is a fast-acting, short-acting non-benzodiazepine sedative hypnotic developed by Sepracor, an American company. It is the dextrorotatory single isomer of zopiclone. It was launched in the United States in April 2005 and in Japan in April 2012. Preclinical and clinical studies have shown that the affinity of this product for benzodiazepine receptors is 50 times that of dextrorotatory zopiclone. Dexzopiclone has the advantages of stronger efficacy and lower toxicity compared with zopiclone.

[0003] (6-(5-chloro-2-pyridyl)-5H-pyrrolo[3,4-b]pyrazine-5,7(6H)-dione) is an intermediate for preparing eszopiclone, and its synthetic route is as follows: .

[0004] At present, there are few literature reports on the detection method of related substances of dexzopiclone intermediate YZ1, and it is difficult to simultaneously and effectively separate the six impurity peaks in intermediate YZ1. In order to strengthen the quality control of dexzopiclone intermediate YZ1 and meet the existing needs, it is urgent to develop a detection method for related substances of dexzopiclone intermediate YZ1. Summary of the invention

[0005] Purpose of the invention: In view of the problems existing in the prior art, the present invention provides a method for detecting related substances of the dexzopiclone intermediate YZ1. By developing and continuously optimizing the detection method, a gradient elution procedure is finally established with a mixed solution of perchloric acid, trifluoroacetic acid and water as mobile phase A and acetonitrile as mobile phase B, thereby achieving effective separation of the intermediate YZ2 and various potential organic impurities.

[0006] Technical solution: The present invention provides a method for detecting related substances of the dexzopiclone intermediate YZ1, comprising the following steps: S1. Prepare the test solution and impurity location solution separately and set aside; S2. Accurately measure equal amounts of the test solution and the impurity location solution, inject them into the high performance liquid chromatograph, use mobile phase A and mobile phase B to separate and analyze by gradient elution, and record the chromatogram; The chromatographic conditions are as follows: octadecylsilane bonded silica gel is used as filler; perchloric acid / trifluoroacetic acid aqueous solution is used as mobile phase A, and acetonitrile is used as mobile phase B; in the perchloric acid / trifluoroacetic acid aqueous solution, the volume ratio of perchloric acid, trifluoroacetic acid and water is 0.1-0.5:1:1000.

[0007] Furthermore, the related substances include one or more of the following compounds: .

[0008] Furthermore, the concentration of the perchloric acid is 70% to 72%.

[0009] Furthermore, the mobile phase is subjected to linear gradient elution with the gradient shown in the following table: .

[0010] Furthermore, the chromatographic conditions also include: Flow rate: 1.0 ml / min; The detection wavelength is 283nm; The column temperature was 30°C; The injection volume was 20 μl.

[0011] Furthermore, the specific preparation method of the test solution is: take the sample to be tested, accurately weigh it, add acetonitrile to dissolve and dilute it, shake it well, filter it, and take the filtrate; the concentration of the test solution is 0.4 mg / ml.

[0012] Furthermore, the specific preparation method of the impurity localization solution is: respectively take pyrazine-2,3-dicarboxylic acid reference substance, pyrazine-2,3-dicarboxylic anhydride reference substance, impurity G reference substance, impurity E reference substance, impurity I reference substance and impurity J reference substance, accurately weigh them, add acetonitrile to dissolve and dilute, shake well, filter, and take the filtrate; the concentration of the impurity localization solution is 20 μg / ml.

[0013] Beneficial effects: Compared with the prior art, the present invention has the following specific beneficial effects: 1. The present invention provides a method for detecting related substances of the intermediate YZ1 of dexzopiclone, which adopts high performance liquid chromatography, has high sensitivity, fast analysis speed, high equipment penetration rate, and is easy to promote.

[0014] 2. In the present invention, perchloric acid and trifluoroacetic acid are added to the mobile phase A, and the impurities can be effectively separated from each other and from the main peak, and the peak shape is good, which is convenient for subsequent analysis of the chromatogram.

[0015] 3. The method has been verified to have good specificity, precision, accuracy, durability and stability. By analyzing the contents of active ingredients and impurities in the dexzopiclone intermediate YZ1, the purity of the dexzopiclone intermediate YZ1 can be monitored to ensure its quality, and the production process of the dexzopiclone intermediate YZ1 can be evaluated. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1It is a linear graph of pyrazine-2,3-dicarboxylic acid with a concentration between 0.0393 μg / ml and 0.7857 μg / ml; Figure 2 The linear graph of pyrazine-2,3-dicarboxylic anhydride with a concentration between 0.0390 μg / ml and 0.7803 μg / ml; Figure 3 It is a linear graph of impurity G with a concentration between 0.0232μg / ml and 38.6280μg / ml; Figure 4 It is a linear graph of impurity E with a concentration between 0.0272 μg / ml and 0.8167 μg / ml; Figure 5 It is a linear graph of impurity I with a concentration between 0.0168 μg / ml and 0.8384 μg / ml; Figure 6 It is the impurity J linear graph with concentration between 0.0160μg / ml and 0.7981μg / ml; Figure 7 It is the linear graph of YZ1 with a concentration between 77.9913μg / ml and 467.9478μg / ml; Figure 8 Specific pyrazine-2,3-dicarboxylic acid spectrum for the detection method validation of related substances of the dexzopiclone intermediate YZ1; Fig. 9 Specific pyrazine-2,3-dicarboxylic anhydride spectrum for the verification of the detection method of related substances of the dexzopiclone intermediate YZ1; Fig.10 Verify the specific impurity E spectrum for the detection method of related substances of the dexzopiclone intermediate YZ1; Fig.11 Verify the specific impurity G spectrum for the detection method of related substances of the dexzopiclone intermediate YZ1; Fig.12 Validation of the specific impurity I spectrum for the detection method of related substances of the dexzopiclone intermediate YZ1; Fig.13 Validation of the specific impurity J spectrum for the detection method of related substances of the dexzopiclone intermediate YZ1; Fig.14 Spectrum of the specific test sample solution for the verification of the detection method of related substances of the intermediate YZ1 of dexzopiclone; Fig.15 Spectrum of the spiked solution for validating the specificity of the detection method for related substances of the dexzopiclone intermediate YZ1. DETAILED DESCRIPTION

[0017] The present invention is described in detail below in conjunction with the embodiments.

[0018] The instruments and chromatographic columns used in the present invention are shown in Table 1:

[0019] The reagents and reference substances used in the present invention are shown in Table 2:

[0020] The solution preparation method used in the present invention is as follows: Perchloric acid and trifluoroacetic acid aqueous solution: Take 0.43 ml of 70%~72% perchloric acid and 1 ml of trifluoroacetic acid, add them into 1000 ml of water and mix well.

[0021] Blank solvent: acetonitrile.

[0022] Pyrazine-2,3-dicarboxylic acid fixing solution: take about 2 mg of pyrazine-2,3-dicarboxylic acid reference substance, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the pyrazine-2,3-dicarboxylic acid stock solution; accurately measure 1 ml of pyrazine-2,3-dicarboxylic acid stock solution, place it in a 50 ml volumetric flask, dilute to the scale with acetonitrile, and shake well.

[0023] Pyrazine-2,3-dicarboxylic anhydride positioning solution: Take about 2 mg of pyrazine-2,3-dicarboxylic anhydride reference substance, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the pyrazine-2,3-dicarboxylic anhydride stock solution; accurately measure 1 ml of pyrazine-2,3-dicarboxylic anhydride stock solution, place it in a 50 ml volumetric flask, dilute to the scale with acetonitrile, and shake well.

[0024] Impurity G localization solution: Take about 12 mg of the impurity G reference substance, accurately weigh it, place it in a 20 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity G stock solution; accurately measure 1 ml of the impurity G stock solution, place it in a 50 ml volumetric flask, dilute to the scale with acetonitrile, and shake well.

[0025] Impurity E localization solution: Take about 2 mg of the impurity E reference substance, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity E stock solution; accurately measure 1 ml of the impurity E stock solution, place it in a 50 ml volumetric flask, dilute to the scale with acetonitrile, and shake well.

[0026] Impurity I localization solution: Take about 1 mg of the impurity I reference substance, accurately weigh it, place it in a 50 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity I stock solution; accurately measure 1 ml of the impurity I stock solution, place it in a 50 ml volumetric flask, dilute to the scale with acetonitrile, and shake well.

[0027] Impurity J localization solution: Take about 2 mg of the impurity J reference substance, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity J stock solution; accurately measure 1 ml of the impurity J stock solution, place it in a 50 ml volumetric flask, dilute to the scale with acetonitrile, and shake well.

[0028] Test solution: Take an appropriate amount of the product, weigh accurately, dissolve in acetonitrile and quantitatively dilute to make a solution containing about 0.4 mg per 1 ml.

[0029] Test sample spiked solution: Take about 40 mg of the product, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve it, accurately add 1 ml of each of the above impurity location solutions, dilute to the scale with acetonitrile, and shake well.

[0030] The chromatographic conditions in the experiment of the present invention are as follows: octadecylsilane bonded silica gel is used as a filler (Merck PurospherSTAR RP-C18, 250 mm×4.6 mm, 5 μm); a perchloric acid-trifluoroacetic acid aqueous solution (0.43 ml of 70%-72% perchloric acid and 1 ml of trifluoroacetic acid are placed in 1000 ml of water and mixed) is used as mobile phase A, acetonitrile is used as mobile phase B, and gradient elution is performed according to the following table; the flow rate is 1.0 ml per minute; the detection wavelength is 283 nm; the column temperature is 30° C.; and the injection volume is 20 μl.

[0031]

[0032] In the present invention, if there are impurity peaks in the chromatogram of the test solution, the impurity G shall not be greater than 5% by peak area normalization method, other individual impurities shall not be greater than 0.10%, and the total impurities shall not be greater than 5%. The chromatogram of the test solution recorded under the related substances shall be calculated by the peak area normalization method, and the YZ1 content shall not be less than 95%.

[0033] Implementation 1: Linear relationship: Pyrazine-2,3-dicarboxylic acid stock solution: Take about 2 mg of pyrazine-2,3-dicarboxylic acid reference substance, accurately weigh it, put it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the pyrazine-2,3-dicarboxylic acid stock solution.

[0034] Pyrazine-2,3-dicarboxylic anhydride stock solution: Take about 2 mg of pyrazine-2,3-dicarboxylic anhydride reference substance, accurately weigh it, put it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the pyrazine-2,3-dicarboxylic anhydride stock solution.

[0035] Impurity G stock solution: Take about 12 mg of the impurity G reference substance, accurately weigh it, place it in a 20 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity G stock solution.

[0036] Impurity E stock solution: Take about 2 mg of the impurity E reference substance, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity E stock solution.

[0037] Impurity I stock solution: Take about 1 mg of the impurity I reference substance, accurately weigh it, place it in a 50 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity I stock solution.

[0038] Impurity J stock solution: Take about 2 mg of the impurity J reference substance, accurately weigh it, place it in a 100 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the impurity J stock solution.

[0039] YZ1 stock solution: Take about 40 mg of YZ1, weigh accurately, put it in a 10 ml volumetric flask, add acetonitrile to dissolve and dilute to the scale, shake well, and use it as the YZ1 stock solution.

[0040] Accurately measure 0.2 ml, 0.5 ml, 0.8 ml, 1.0 ml, 1.2 ml and 2.0 ml of pyrazine-2,3-dicarboxylic acid stock solution, pyrazine-2,3-dicarboxylic anhydride stock solution, impurity G stock solution, impurity E stock solution, impurity I stock solution and impurity J stock solution respectively, place them in 50 ml volumetric flasks, dilute to the scale with acetonitrile, shake well and use them as linear 1, linear 2, linear 3, linear 4, linear 5 and linear 6 solutions respectively.

[0041] Accurately measure the above solution and the quantitative limit solution, inject them into the liquid chromatograph respectively, record the chromatogram, and calculate the linear regression equation, such as Figure 1-6 shown.

[0042] The results showed that pyrazine-2,3-dicarboxylic acid had a good linear relationship in the concentration range of 0.0393μg / ml~0.7857μg / ml, and the linear regression equation was: y=190735x-7616.2, r=0.9996.

[0043] The linear relationship of pyrazine-2,3-dicarboxylic anhydride was good in the concentration range of 0.0390μg / ml~0.7803μg / ml, and the linear regression equation was: y=198838x-7615.9, r=0.9997.

[0044] Impurity G has a good linear relationship in the concentration range of 0.0232μg / ml~38.6280μg / ml, and the linear regression equation is: y=53866x-16918, r=0.9998.

[0045] Impurity E has a good linear relationship in the concentration range of 0.0272μg / ml~0.8167μg / ml, and the linear regression equation is: y=39292x+209.2, r=0.9999.

[0046] Impurity I has a good linear relationship in the concentration range of 0.0168μg / ml~0.8384μg / ml, and the linear regression equation is: y=70140x+1012.8, r=0.9995.

[0047] Impurity J has a good linear relationship in the concentration range of 0.0160μg / ml~0.7981μg / ml, and the linear regression equation is: y=68520x-97.698, r=0.9998.

[0048] Accurately measure 0.2ml, 0.5ml, 0.8ml, 1.0ml and 1.2ml of YZ1 stock solution, place them in 10ml volumetric flasks respectively, dilute to the scale with acetonitrile, shake well, and use them as YZ1 linear 1, linear 2, linear 3, linear 4 and linear 5 solutions.

[0049] Accurately measure YZ1 linear 1 to linear 5 solutions, inject them into the liquid chromatograph respectively, record the chromatogram, and calculate the linear regression equation, such as Figure 7 shown.

[0050] The results showed that YZ1 had a good linear relationship in the concentration range of 77.9913μg / ml~467.9478μg / ml, and the linear regression equation was: y=52919x+2E+06, r=0.9962.

[0051] Actual sample testing (taking the determination of 6 batches of YZ1 samples from Jiangsu Tasly Lili Diyi Pharmaceutical Co., Ltd. as an example): Accurately measure equal amounts of the test solution and the impurity location solution, inject them into the high performance liquid chromatograph, and record the chromatogram. The chromatographic conditions are as follows: octadecylsilane bonded silica gel is used as the filler (Merck Purospher STAR RP-C18, 250mm×4.6mm, 5μm); perchloric acid trifluoroacetic acid aqueous solution (take 0.43ml of 70%~72% perchloric acid and 1ml of trifluoroacetic acid, put them in 1000ml water, mix well) as the mobile phase A, acetonitrile as the mobile phase B, and perform gradient elution according to Table 3; the flow rate is 1.0ml per minute; the detection wavelength is 283nm; the column temperature is 30℃; the injection volume is 20μl.

[0052]

[0053] Implementation 2: Exclusive properties: Accurately measure pyrazine-2,3-dicarboxylic acid positioning solution, pyrazine-2,3-dicarboxylic anhydride positioning solution, impurity G positioning solution, impurity E positioning solution, impurity I positioning solution, impurity J positioning solution, test sample solution and test sample spiked solution, respectively, and inject them into the liquid chromatograph, record the chromatogram, and investigate the blank solvent, the interference with the related substances and content determination of the right-zopiclone intermediate YZ1, and the separation between the peaks. The results are shown in Table 5.

[0054]

[0055] The results showed that in the spiked chromatogram of the test sample, the order of peaks was pyrazine-2,3-dicarboxylic acid / pyrazine-2,3-dicarboxylic anhydride, impurity E, impurity G, YZ1, impurity J, and impurity I; the blank solvent did not interfere with the determination of YZ1, and the impurity peaks could be effectively separated from the YZ1 peak. The analytical method for the determination of related substances and content of the dexzopiclone intermediate YZ1 had good specificity.

[0056] Repeatability: According to the analytical method for the determination of related substances and content of the intermediate YZ1 of right zopiclone, 6 test sample solutions were determined. The RSD of impurity G, other single impurities, total impurities and content in the 6 test sample solutions were investigated, and the results are shown in Table 6.

[0057]

[0058] The results showed that the analytical method for the determination of related substances and content of the dexzopiclone intermediate YZ1 had good repeatability.

[0059] Intermediate precision: Different personnel were investigated on different dates and using different instruments to determine the test solution according to the analytical method for related substances and content determination of the intermediate YZ1 of dexzopiclone. The RSD of impurity G, other single impurities, total impurities and content in the test solution (a total of 12 portions, including 6 portions under the repeatability item) were investigated. The results are shown in Table 7.

[0060]

[0061] The results showed that the intermediate precision of the analytical method for the determination of related substances and content of the dexzopiclone intermediate YZ1 was good.

[0062] Limit of Detection and Limit of Quantitation: The detection limit and quantification limit were determined by the signal-to-noise ratio method. The corresponding concentration when the signal-to-noise ratio was about 3:1 was taken as the detection limit, and the corresponding concentration when the signal-to-noise ratio was about 10:1 was taken as the quantification limit.

[0063] (1) Detection limit of pyrazine-2,3-dicarboxylic acid Accurately measure 3 ml of the pyrazine-2,3-dicarboxylic acid quantitative limit solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the pyrazine-2,3-dicarboxylic acid detection limit solution. The detection limit concentration is 0.0118 μg / ml, which is 2.95% of the limit.

[0064] (2) Limit of quantification of pyrazine-2,3-dicarboxylic acid Accurately measure 5 ml of pyrazine-2,3-dicarboxylic acid linear 1 solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the quantification limit solution of pyrazine-2,3-dicarboxylic acid. The quantification limit concentration is 0.0393 μg / ml, which is 9.82% of the limit.

[0065] The quantification limit solution of pyrazine-2,3-dicarboxylic acid was taken and injected 6 times to examine the peak area RSD. The results are shown in Table 8.

[0066]

[0067] The results showed that the quantification limit solution of pyrazine-2,3-dicarboxylic acid had good precision.

[0068] (3) Detection limit of pyrazine-2,3-dicarboxylic anhydride Accurately measure 3 ml of the quantitative limit solution of pyrazine-2,3-dicarboxylic anhydride, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the detection limit solution of pyrazine-2,3-dicarboxylic anhydride. The detection limit concentration is 0.0117 μg / ml, which is 2.92% of the limit.

[0069] (4) Limit of quantification of pyrazine-2,3-dicarboxylic anhydride Accurately measure 5 ml of pyrazine-2,3-dicarboxylic anhydride linear 1 solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the quantification limit solution of pyrazine-2,3-dicarboxylic anhydride. The quantification limit concentration is 0.0390 μg / ml, which is 9.75% of the limit.

[0070] The quantitative limit solution of pyrazine-2,3-dicarboxylic anhydride was taken and injected 6 times to examine the peak area RSD. The results are shown in Table 9.

[0071]

[0072] The results showed that the quantification limit solution of pyrazine-2,3-dicarboxylic anhydride had good precision.

[0073] (5) Detection limit of impurity G Accurately measure 3 ml of the impurity G quantitative limit solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the impurity G detection limit solution. The detection limit concentration is 0.0070 μg / ml, which is 0.035% of the limit.

[0074] (6) Impurity G Quantification Limit Accurately measure 0.2 ml of impurity G linear 1 solution, place it in a 50 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, then accurately measure 1 ml, place it in a 100 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, as the impurity G quantitative limit solution, the quantitative limit concentration is 0.0232 μg / ml, which is 0.116% of the limit.

[0075] The quantitative limit solution of impurity G was taken and injected 6 times repeatedly to examine the peak area RSD. The results are shown in Table 10.

[0076]

[0077] The results showed that the precision of the quantitative limit solution of impurity G was good.

[0078] (7) Detection limit of impurity E Accurately measure 3 ml of the quantitative limit solution of impurity E, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the detection limit solution of impurity E. The detection limit concentration is 0.0082 μg / ml, which is 2.05% of the limit.

[0079] (8) Impurity E quantitative limit Accurately measure 5 ml of impurity E linear 1 solution, place it in a 15 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the impurity E quantitative limit solution. The quantitative limit concentration is 0.0272 μg / ml, which is 6.80% of the limit.

[0080] The quantitative limit solution of impurity E was taken and injected 6 times repeatedly to examine the peak area RSD. The results are shown in Table 11.

[0081]

[0082] The results showed that the precision of the quantitative limit solution of impurity E was good.

[0083] (9) Impurity I detection limit Accurately measure 3 ml of the quantitative limit solution of impurity I, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the detection limit solution of impurity I. The detection limit concentration is 0.0050 μg / ml, which is 1.25% of the limit.

[0084] (10) Impurity I quantitative limit Accurately measure 2 ml of impurity I linear 1 solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use this as the impurity I quantitative limit solution. The quantitative limit concentration is 0.0168 μg / ml, which is 4.20% of the limit.

[0085] The quantitative limit solution of impurity I was taken and repeated injection was performed 6 times to examine the peak area RSD. The results are shown in Table 12.

[0086]

[0087] The results showed that the precision of the quantitative limit solution of impurity I was good.

[0088] (11) Detection limit of impurity J Accurately measure 3 ml of the impurity J quantitative limit solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use it as the impurity J detection limit solution. The detection limit concentration is 0.0048 μg / ml, which is 1.20% of the limit.

[0089] (12) Impurity J quantitative limit Accurately measure 2 ml of impurity J linear 1 solution, place it in a 10 ml volumetric flask, add acetonitrile to dilute to the scale, shake well, and use this as the impurity J quantitative limit solution. The quantitative limit concentration is 0.0160 μg / ml, which is 4.00% of the limit.

[0090] Take the quantitative limit solution of impurity J and repeat the injection 6 times to examine the peak area RSD. The results are shown in Table 13.

[0091]

[0092] The results showed that the precision of the quantitative limit solution of impurity J was good.

[0093] Durability: According to the analytical method for the determination of related substances and contents of the intermediate YZ1 of right-zopiclone, the RSD of impurity G, other single impurities, total impurities and content in the test solution were investigated under different wavelengths (283±2nm), different flow rates (1.0±0.1ml / min) and different chromatographic column conditions. The results are shown in Table 14.

[0094]

[0095] The results showed that the analytical method for the determination of related substances and content of the dexazopiclone intermediate YZ1 had good durability.

[0096] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting related substances of the dexazopiclone intermediate YZ1, characterized in that: The following steps are involved: S1. Prepare the test solution and impurity location solution separately and set aside; S2. Accurately measure equal amounts of the test solution and the impurity location solution, inject them into the high performance liquid chromatograph, use mobile phase A and mobile phase B to separate and analyze by gradient elution, and record the chromatogram; The chromatographic conditions are as follows: octadecylsilane bonded silica gel is used as filler; perchloric acid / trifluoroacetic acid aqueous solution is used as mobile phase A, and acetonitrile is used as mobile phase B; in the perchloric acid / trifluoroacetic acid aqueous solution, the volume ratio of perchloric acid, trifluoroacetic acid and water is 0.1-0.5:1:1000.

2. The method for detecting related substances of the dexazopiclone intermediate YZ1 according to claim 1, characterized in that: The related substances include one or more of the following compounds: 。 3. The method for detecting related substances of the dexazopiclone intermediate YZ1 according to claim 1, characterized in that: The concentration of the perchloric acid is 70% to 72%.

4. The method for detecting related substances of the dexazopiclone intermediate YZ1 according to claim 1, characterized in that: The mobile phase is subjected to linear gradient elution as shown in the following table: 。 5. The method for detecting related substances of the dexazopiclone intermediate YZ1 according to claim 1, characterized in that: Chromatographic conditions also include: Flow rate: 1.0 ml / min; The detection wavelength is 283nm; The column temperature was 30°C; The injection volume was 20 μl.

6. The method for detecting related substances of the dexazopiclone intermediate YZ1 according to claim 1, characterized in that: The specific preparation method of the test solution is: take the sample to be tested, accurately weigh it, add acetonitrile to dissolve and dilute it, shake it well, filter it, and take the filtrate; the concentration of the test solution is 0.4 mg / ml.

7. The method for detecting related substances of the dexazopiclone intermediate YZ1 according to claim 1, characterized in that: The specific preparation method of the impurity localization solution is: respectively take pyrazine-2,3-dicarboxylic acid reference substance, pyrazine-2,3-dicarboxylic anhydride reference substance, impurity G reference substance, impurity E reference substance, impurity I reference substance and impurity J reference substance, accurately weigh them, add acetonitrile to dissolve and dilute, shake well, filter, and take the filtrate; the concentration of the impurity localization solution is 20 μg / ml.

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