Method for detecting dimethyl carbamyl chloride in palmitoyl chloride and application

Abstract

The invention provides a method for detecting dimethyl carbamyl chloride in palmitoyl chloride and application, and belongs to the technical field of pharmaceutical chemistry detection. The method comprises the following steps: mixing dimethyl carbamate (DMCC-DER) with a diluent to prepare a standard solution; mixing palmitoyl chloride with a diluent, heating, and cooling to obtain a sample solution; detecting the purity of the standard substance solution and the sample solution obtained in the step (1) and the step (2); and the diluent is methanol. The method is simple to operate, reagents are easy to obtain, the sensitivity can reach 3.0 mu g / ml, the accuracy is high, the reproducibility is good, and reference and technical support are provided for quality control of DMCC and safety and quality controllability of subsequent pharmaceutical products.

Description

TECHNICAL FIELD

[0001] The application provides a method for detecting dimethylcarbamoyl chloride in palmitoyl chloride and application, and belongs to the technical field of pharmaceutical chemistry detection. BACKGROUND

[0002] Dimethylcarbamoyl chloride (DMCC) has relatively large polarity and high activity, and cannot be directly detected. However, DMCC is also a common chemical reagent, which is often present in the synthesis of pharmaceutical and pesticide products, and is usually generated by the substitution reaction of N,N-dimethylformamide (DMF) and hydrochloric acid, or the substitution reaction of DMF and sulfonyl chloride / carbon chloride.

[0003] Taking the pharmaceutical intermediate palmitoyl chloride as an example, the addition of DMF can significantly improve the yield and avoid the generation of by-product palmitic anhydride in the process of generating palmitic acid from palmitic acid. However, DMF may form DMCC through Vilsmeier reaction with the chlorinating agent in the process.

[0004] DMCC is a genotoxic impurity, which is a colorless to yellow liquid with irritancy and toxicity. Controlling the limit of DMCC is very important for drug safety. DMCC belongs to carbon chloride, has the commonness of acyl chloride, is easy to decompose in the presence of active hydrogen, is unstable to high temperature, and if GC direct injection is adopted, the acyl chloride group will undergo acylation reaction with the coating layer of the GC chromatographic column, resulting in failure of the chromatographic column.

[0005] Ding Qianqian et al. studied the detection method of DMCC in glucoside sodium in GC-MS method for determination of genotoxic impurity dimethylcarbamoyl chloride in glucoside sodium (China Medical Science 13.21 (2023): 80-83). The specific method is as follows: accurately weigh 575 mg of glucoside sodium in a 10 ml volumetric flask, dilute to the mark with ether, shake and centrifuge with a glass centrifuge tube as a test solution; accurately weigh 575 mg of glucoside sodium in a 10 ml volumetric flask, add DMCC control product stock solution, dilute to 40 ng of DMCC per milliliter with ether as a mixed solution. The study found that the response value of the chromatographic peak did not meet the requirements when the split ratio of the sample was 5:1, and the response value of the mass spectrum peak was high when the sample was not split; the DMCC peak type detected by the VF-WAXms capillary column was not good.

[0006] The experiment screened water solvents that can dissolve both glucoside sodium and DMCC, but the acyl chloride bond (-COCl) in the structure is unstable and easy to break in water. The experiment also investigated organic solvents such as ether, acetonitrile and alcohol, and the results showed that DMCC has good solubility and best stability in ether. At the same time, since the GC-MS used is sensitive, the chromatographically pure ether is preferentially selected.

[0007] However, diethyl ether is a special dangerous chemical, and its purchase procedure is complicated and complex. The GC-MS instrument is expensive, and cannot be popularized in the workshop of a pharmaceutical factory. In addition, the requirements for the instrument user are high, and therefore, there are certain limitations.

[0008] Martina Stare et al. in Investigation on the Formation and Hydrolysis of N,N-Dimethylcarbamoyl Chloride (DMCC) in Vilsmeier Reactions Using GC / MS as the Analytical Detection Method (Organic Process Research & Development 2009, 13, 857-862) developed a very useful analytical procedure for the detection and quantification of trace amounts of DMCC formed in VR: the method is based on the derivatization of DMCC with ethanol to form ethyl N,N-dimethylcarbamate and analysis by gas chromatography coupled with a mass spectrometer in selected ion monitoring mode. The analytical method has selectivity and good linearity. The limits of detection and quantification for DMCC were determined by the standard addition method and were LOD = 0.2 ppm and LOQ = 0.7 ppm, respectively.

[0009] GC / MS-SIM analysis sample preparation: 4 samples (about 0.5 g) were taken simultaneously from the reaction mixture and weighed. The samples were added to 4 separate 5 ml test tubes with C2H5OH (1 ml) and heated to 70°C. The test tubes were equipped with a magnetic stirrer, and the interlayer was permeated with a glass capillary blood vessel. The test tubes were placed in a heating block. 0.5 mL of acetonitrile was added to one of the test tubes, and a DMCC standard (0.5 mL) was added to the other three. After one hour, the mixture was cooled to room temperature. Saturated NaHCO3 (1-2 mL) and H2O (1-2 mL) were added to each test tube to bring the pH of the solution to 8-9. Each sample was extracted with a CH2Cl2 (2 mL) mixture with 50 ppm of naphthalene (internal standard). The organic phase obtained from each sample was first dried with anhydrous sodium sulfate and then subjected to gas chromatography / mass spectrometry analysis.

[0010] The sample preparation method of this method is complex, and needs to be used with a mass spectrometer, which is expensive. SUMMARY

[0011] The present application aims at the problems existing in the prior art, and provides a method for detecting dimethyl carbamoyl chloride in palmitoyl chloride and application, the method is simple to operate, only needs to heat the reaction in a solution state, does not need to perform other cumbersome operations, reagents are easy to obtain, the sensitivity can reach 3.0 mu g / ml, the accuracy is high, the reproducibility is good, and reference and technical support are provided for quality control of DMCC and controllability of safety and quality of subsequent pharmaceutical products.

[0012] To achieve the above object, the technical scheme adopted by the present application is as follows: In a first aspect, the present application provides a method for detecting dimethyl carbamoyl chloride in palmitoyl chloride, characterized in that the method comprises the following steps: (1) mixing methyl dimethylcarbamate with a diluent to configure a standard solution; (2) mixing, heating and cooling palmitoyl chloride with a diluent to obtain a sample solution; (3) detecting the purity of methyl dimethylcarbamate in the standard solution and the sample solution obtained in steps (1) and (2); The diluent is methanol.

[0013] Further, the methanol is anhydrous methanol.

[0014] Further, the heating temperature in step (2) is 50-70 DEG C, and the heating time is 0.5-2 h.

[0015] Further, the heating temperature in step (2) is 50-60 DEG C, and the heating time is 0.5-1 h.

[0016] Further, the heating temperature in step (2) is 60 DEG C, and the heating time is 1 h.

[0017] Further, the ratio of palmitoyl chloride to diluent in step (2) is (180-220) mg:10 mL.

[0018] Further, the ratio of palmitoyl chloride to diluent in step (2) is (200-220) mg:10 mL.

[0019] Further, the ratio of palmitoyl chloride to diluent in step (2) is 200 mg:10 mL.

[0020] Further, the purity detection in step (3) is gas chromatography detection.

[0021] Further, the carrier gas for the gas chromatography detection is nitrogen, and the carrier gas flow rate is 1.0-3.0 mL / min.

[0022] Further, the carrier gas for the gas chromatography detection is nitrogen, and the carrier gas flow rate of the carrier gas is 2.0-3.0 mL / min.

[0023] Further, the split ratio of the gas chromatography detection is (3-10):1.

[0024] Further, the split ratio of the gas chromatography detection is (3-5):1.

[0025] Further, the temperature rising program of the gas chromatography detection is: 60-80℃ for 4 min, rising to 280-300℃ at a speed of 10-20℃ / min, and keeping for 10-15 min.

[0026] Further, the temperature rising program of the gas chromatography detection is: 80℃ for 4 min, rising to 280℃ at a speed of 20℃ / min, and keeping for 10 min.

[0027] Further, the injection port temperature and detector temperature of the gas chromatography detection are 280-300℃.

[0028] Further, the column model of the gas chromatography detection is RESTEK Rtx-5 Amine.

[0029] Further, the detector of the gas chromatography detection is FID.

[0030] In the second aspect, the application provides the application of the method in controlling the production quality of palmitoyl chloride.

[0031] The application has the following technical effects: The application uses methanol as a derivatization reagent to convert DMCC into methyl dimethylcarbamate (DMCC-DER) under heating conditions, and the reaction equation is as follows: .

[0032] The method has the advantages of simple operation, easy-to-obtain reagent, sensitivity up to 3.0 μg / ml, high accuracy, good reproducibility, and the like, and provides a reference and technical support for DMCC quality control and subsequent pharmaceutical product safety and quality controllability, and has practical significance. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The gas chromatogram of the blank solution.

[0034] Figure 2 The gas chromatogram of the limit of quantification solution (3.0 μg / ml DMCC-DER).

[0035] Figure 3Gas chromatogram for standard solution STD (10.0 pg / ml DMCC-DER).

[0036] Figure 4 Gas chromatogram for sample solution (20 mg / ml palmitoyl chloride).

[0037] Figure 5 Linear plot and residual plot.

[0038] Figure 6 Gas chromatogram for Comparative Example 1, blue is DMCC, red is MEOH.

[0039] Figure 7 Gas chromatogram for Comparative Example 1 blank, LOQ and STD, where blue is STD, red is methanol, green is LOQ.

[0040] Figure 8 Gas chromatogram for DMCC heated for 30 min and 50 min, blue is 50 min, red is 30 min.

[0041] Figure 9 Gas chromatogram for DMCC heated for 1 h, 1.5 h and 2 h, red is 1 h, green is 1.5 h, blue is 2 h.

[0042] Figure 6 , 7 The solvent peak in Figure 9 is higher, so there is no complete screenshot to see the target peak, which does not affect the technical effect.

[0043] Figures 1-4 and Figures 6-9 Gas chromatography detection result figure, directly generated by computer, font is small, in order to see the target peak, there is no complete screenshot, which does not affect the technical effect.

[0044] The horizontal coordinate unit of Figures 1-4 and Figures 6-9 is min, and the vertical coordinate unit is pA.

[0045] The horizontal coordinate of Figure 7 from left to right is 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, and the vertical coordinate from bottom to top is 18, 19, 20, 21, 22, 23, 24. Figure 9 The horizontal coordinate of from left to right is 2, 3, 4, 5, 6, 7, 8, and the vertical coordinate from bottom to top is 20, 21, 22, 23, 24, 25, 26, 27, 28. DETAILED DESCRIPTION

[0046] Following, the embodiments of the present application are described through specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure of the present specification. The present application can also be implemented or applied through other different embodiments, and the details in the present specification can be modified or changed based on different views and applications without departing from the spirit of the present application.

[0047] Before further describing the embodiments of the present application, it should be understood that the scope of protection of the present application is not limited to the specific embodiments described below; it should also be understood that the terms used in the embodiments of the present application are used to describe the specific embodiments, not to limit the scope of protection of the present application.

[0048] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified by the present application, both ends of each numerical range and any number between the two ends can be selected. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0049] It is worth noting that, unless otherwise specified, the raw materials used in the present application are ordinary commercially available products, and their sources are not specifically limited.

[0050] Example 1: A method for detecting dimethylcarbamoyl chloride 1.1 Instruments Gas chromatograph Agilent 8890, electronic analytical balance (100,000th).

[0051] 1.2 Reagents Anhydrous methanol, methyl dimethylcarbamate (DMCC-DER) standard.

[0052] 1.3 Chromatographic conditions The chromatographic conditions are shown in Table 1.

[0053] Table 1

[0054] 1.4 Solution preparation The solution preparation is shown in Table 2.

[0055] Table 2

[0056] 1.5 Detection process According to the sequence of Table 3, the sample was injected.

[0057] Table 3

[0058] 1) The last injection is a system blank, the others are balance systems. 2) After every 5 injections, add STD1 as a check.

[0059] Ensure the system meets the following parameters: 1) The blank is interference-free (at the DMCC-DER peak position, the area of the interference peak in the blank is less than 50% of the LOQ area). 2) The signal-to-noise ratio of the main peak in the limit of quantification solution is greater than 10. 3) The response factor RSD of all STD1 is ≤2.0%. 4) The recovery rate between STD1 and STD2 is 98.0-102.0%.

[0060] Material parameters are shown in Table 4.

[0061] Table 4

[0062] Molecular weight conversion factor = 103.1 / 107.5.

[0063] 1.6 Calculation method The content of DMCC is calculated by external standard method, the formula is as follows:

[0064] Where: R i : The response factor of DMCC in the sample solution; R s : The average response factor of DMCC-DER in the first 6 injections of STD1 solution; P s : The content of DMCC-DER standard, %.

[0065] Molecular weight conversion factor: 0.96.

[0066] DMCC-DER chromatographic parameters are shown in Table 5.

[0067] Table 5

[0068] 1.7 Reporting results requirements: 1) Only integrate DMCC-DER, do not integrate the rest of the peaks. 2) Report the average of two samples.

[0069] 3) When the calculated result is less than 150 ppm, report <150 ppm, when the calculated result is greater than 150 ppm, report the measured value.

[0070] Figure 1 Gas chromatogram of blank solution, Figure 2 Gas chromatogram of limit of quantification solution (3.0 μg / ml DMCC-DER), Figure 3 Gas chromatogram of standard solution STD (10.0 μg / ml DMCC-DER), Figure 4 Gas chromatogram of sample solution (20 mg / ml palmitoyl chloride).

[0071] The gas chromatogram table of standard solution is shown in Table 6.

[0072] Table 6

[0073] Comparative Example 1 The standard solution is the same as Example 1, and the sample solution is different from Example 1 in that DMCC is heated at 60°C for half an hour.

[0074] The chromatographic conditions are shown in Table 7.

[0075] Table 7

[0076] The DMCC-DER derived under the above method has too early peak, such as Figure 6 .

[0077] The temperature program is optimized, as shown in Table 8.

[0078] Table 8

[0079] As Figure 7 , the figure is blank, LOQ (DMCC-DER), STD (DMCC-DER) superimposed, blue is STD, red is methanol, and green is LOQ. DMCC has retention on the chromatographic column after derivation under the above method, but the peak shape is poor.

[0080] The chromatographic column of the optimized method is changed to RESTEK Rtx-5 Amine. The rest of the detection parameters remain unchanged, and the derivation conditions of DMCC are screened.

[0081] Figure 8 The results of DMCC heated at 60°C for 30 min and 50 min, respectively. Blue is 50 min, and red is 30 min.

[0082] Figure 9 The results of DMCC heated at 60°C for 1 h, 1.5 h and 2 h, respectively. Red is 1 h, green is 1.5 h, and blue is 2 h.

[0083] Under the above method, both DMCC and DMCC-DER are retained on the chromatographic column, and the effect is obviously better at 60°C for 50 min than for 30 min, but it is still not completely derivatized. When the time is extended to 1 h, no peak of DMCC is detected, and no change is observed after further extending the derivatization time. Therefore, the optimal derivatization condition is 60°C for 1 h.

[0084] 2. Test example: method validation The verification results of Example 1 are summarized in Table 9.

[0085] Table 9

[0086] (1) System suitability ① At the peak position of DMCC-DER, the blank solution (diluent) should not have interference. If there is interference, the area of the interference peak should be less than 50% of the peak area of the limit of quantification solution.

[0087] The gas chromatogram of the blank solution (anhydrous methanol) is shown in Figure 1 , and the gas chromatogram of the limit of quantification solution (3.0 μg / ml DMCC-DER) is shown in Figure 2 . It can be seen that there is no interference at the peak position of DMCC-DER (7.051 min).

[0088] The table of the gas chromatogram of the limit of quantification solution is shown in Table 10.

[0089] Table 10

[0090] ② In the same sequence, 6 injections (STD1) + 1 injection (STD2) of DMCC-der standard solution are continuously injected. The RSD of the response factors of all 6 injections of STD1 is less than 2%, and the recovery rate of STD1 and STD2 should be between 98.0-102.0%.

[0091] The results are shown in Table 11.

[0092] Table 11

[0093] (2) Accuracy and precision Configuration 12 concentration of 20 mg / ml of palmitoyl chloride solution, divided into four groups, respectively, to add the blank solution and 3 levels of DMCC, configuration of the following levels of DMCC solution: blank (Blank-1~Blank-3), 3.0 μg / ml (LOQ-1~LOQ-3), 10.0 μg / ml (100%-1~100%-3), 20.0 μg / ml (200%-1~200%-3), the ratio between the measured value and the added value, the recovery rate is between 75-125%, RSD≤10.0%.

[0094] The detection results are shown in Table 12.

[0095] Table 12

[0096] (3) Linearity Configuration DMCC solution 6: LOQ (3.0 μg / ml), L-50% (5.0 μg / ml), L-100% (10.0 μg / ml), L-120% (12 μg / ml), L-150% (15.0 μg / ml), L-200% (20.0 μg / ml), after derivation in turn two needle, record peak area, regression curve by least squares method, record regression equation, correlation coefficient R 2 and residual sum of squares, R 2 greater than 0.998, residual sum of squares less than or equal to 0.1. The results are shown in Table 13 and Table 14.

[0097] DMCC linear graph and residual graph are shown in Figure 5 .

[0098] Table 13

[0099] Table 14

[0100] (4) Detection limit and limit of quantification Configuration 6 concentration of 3 μg / mL DMCC-DER solution as the limit of quantification solution (LOQ), continuous sampling 6 needle, evaluation of DMCC-DER peak signal to noise ratio. The signal to noise ratio is greater than 10.

[0101] Configuration 6 concentration of 1.5 μg / mL DMCC-DER solution as the limit of detection solution (LOD), continuous sampling 6 needle, evaluation of DMCC-DER peak signal to noise ratio. The signal to noise ratio is greater than 3.

[0102] The detection results are shown in Table 15 and Table 16.

[0103] Table 15

[0104] Table 16

[0105] (5) Stability Using STD1 (DMCC-DER) solution as the standard stability solution, samples were injected at 0h, 4h, 12h, 19h and 24h to evaluate the difference in DMCC-DER content relative to 0h, and the relative deviation RD% was used for evaluation.

[0106] Using a 100%-1 spiking solution as the stability solution for the test sample, the sample was injected at 0h, 4h, 12h, 19h, and 24h to assess the difference in DMCC-DER content relative to 0h, which was evaluated using the relative deviation RD%. The results are shown in Tables 17 and 18.

[0107] Table 17

[0108] Table 18

[0109] Conclusion: The standard and spiked sample solutions were stable at room temperature for 19 hours.

[0110] The methanol derivatization method of the present invention is simple to operate and does not require expensive instruments and reagents. However, problems such as poor peak shape and incomplete derivatization efficiency are encountered during the research process. The technical solution of the present invention solves the above problems.

[0111] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for detecting dimethylcarbamoyl chloride in palmitoyl chloride, characterized in that, Includes the following steps: (1) Mix methyl dimethylcarbamate with a diluent to prepare a standard solution; (2) Mix palmitoyl chloride with diluent, heat and cool to obtain sample solution; (3) The purity of methyl dimethylcarbamate was tested on the standard solution and sample solution obtained in steps (1) and (2); The diluent is methanol.

2. The method according to claim 1, characterized in that, The methanol in question is anhydrous methanol.

3. The method according to claim 1, characterized in that, The heating temperature in step (2) is 50-70℃ and the heating time is 0.5-2h.

4. The method according to claim 1, characterized in that, In step (2), the ratio of palmitoyl chloride to diluent is (180-220) mg: 10 mL.

5. The method according to claim 1, characterized in that, The purity detection in step (3) is performed by gas chromatography.

6. The method according to claim 5, characterized in that, The carrier gas used in the gas chromatography detection is nitrogen, and the carrier gas flow rate is 1.0-3.0 mL / min.

7. The method according to claim 5, characterized in that, The split ratio for gas chromatography detection is (3-10):

1.

8. The method according to claim 5, characterized in that, The temperature program for gas chromatography detection is as follows: hold at 60-80℃ for 4 minutes, then increase to 280-300℃ at a rate of 10-20℃ / min and hold for 10-15 minutes.

9. The method according to claim 8, characterized in that, The temperature program for gas chromatography detection is as follows: hold at 80°C for 4 minutes, then increase to 280°C at a rate of 20°C / min and hold for 10 minutes.

10. The use of the method according to any one of claims 1-9 in controlling the production quality of palmitoyl chloride.

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