Acetaminophen disinfection by-product as well as preparation method and application thereof

Abstract

The invention discloses an acetaminophen disinfection by-product as well as a preparation method and application thereof, belongs to the technical field of environmental chemistry and organic synthesis, and particularly relates to two acetaminophen disinfection by-products, namely a compound P186 and a compound P220. According to the method, a column chromatography gradient elution system is established by simulating the reaction of acetaminophen and sodium hypochlorite during water disinfection, and analysis instruments such as a high performance liquid chromatography-quadrupole-time-of-flight mass spectrometer, high performance liquid chromatography, carbon-13 nuclear magnetic resonance, hydrogen-1 nuclear magnetic resonance and a Fourier transform infrared instrument are combined, so that the content of acetaminophen in water is detected, and the content of acetaminophen in water is detected. And analyzing and identifying the structures and the purities of the compound P186 and the compound P220. The method can provide standard samples and technical support for the conversion mechanism, toxicity evaluation and pollution prevention and control of the acetaminophen disinfection by-product in the environment.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis and environmental chemistry technology, specifically relating to acetaminophen disinfection byproduct compounds P186 and P220, their preparation methods, and applications. Background Technology

[0002] Acetaminophen is a widely used over-the-counter antipyretic and analgesic, often combined with other medications in compound preparations. After human ingestion, some acetaminophen, both unchanged and metabolites, enters municipal wastewater systems through excrement. Because traditional wastewater treatment processes struggle to completely remove it, acetaminophen is discharged into natural water bodies via effluent. Furthermore, medical wastewater, drug abuse, and the indiscriminate disposal of expired medications also contribute to its entry into natural aquatic environments. Due to its widespread use, complex pathways of entry into water bodies, and environmental persistence, acetaminophen is frequently detected in various aquatic environments and is a typical trace organic pollutant of concern in current environmental chemical and ecological risk assessments.

[0003] Chlorination disinfection is a primary means of ensuring drinking water safety. Sodium hypochlorite, an inorganic chlorine-containing disinfectant, possesses strong oxidizing properties and is widely used in the disinfection and purification processes of water supply systems. However, during water treatment, sodium hypochlorite reacts with organic matter and other substances in the water to produce chlorination disinfection byproducts, posing potential hazards to human health and the environment. Studies have found that nitrogen-containing disinfection byproducts generated from precursors through chlorination disinfection are more toxic than conventional carbon-containing disinfection byproducts, exhibiting stronger polarity and hydrophilicity, and migrating more easily with water than conventional disinfection byproducts, thus being widely present in chlorinated drinking water. Existing research data indicates that nitrogen-containing disinfection byproducts can increase oxidative stress levels and possess carcinogenic and mutagenic properties.

[0004] Acetaminophen in water can generate various disinfection byproducts during water disinfection. Currently, there are no systematic reports on acetaminophen disinfection byproducts. Summary of the Invention

[0005] In order to solve the above-mentioned technical problems, the purpose of this invention is to provide a disinfection byproduct of acetaminophen, its synthesis method and application.

[0006] To achieve the above-mentioned objective, the technical solution adopted by the present invention is: acetaminophen disinfection byproducts, wherein the acetaminophen disinfection byproducts are compound P186 with structural formula (I) and compound P220 with structural formula (II).

[0007] and

[0008] The preparation method of acetaminophen disinfection byproduct compound P186 includes the following steps: (1) Synthesis of crude extract of disinfection byproduct of acetaminophen: Dissolve acetaminophen (APAP) in purified water, add sodium hypochlorite solution, stir the reaction at room temperature for 3-4 h, and dry under vacuum to obtain crude product.

[0009] (2) Dissolve the crude product in methanol and mix it evenly with silica gel, then dry it and load it into a silica gel column. Use a solvent with a volume ratio of dichloromethane:methanol = 100:1 as the eluent to elute and collect the separated fractions. (3) The fractions were monitored by thin-layer chromatography, and the fractions with the same Rf value were combined. The solvent was removed by rotary evaporation to obtain the purified compound P186.

[0010] Further, step (3) specifically involves using a solvent with a volume ratio of dichloromethane:methanol = 15:1 as the developing solvent, monitoring each fraction by thin-layer chromatography, merging all fractions with an Rf value of 0.37, concentrating by rotary evaporation to remove the solvent, and obtaining the purified compound P186.

[0011] The preparation method of acetaminophen disinfection byproduct compound P220 includes the following steps: (1) Synthesis of crude extract of disinfection byproduct of acetaminophen: Dissolve acetaminophen in purified water, add sodium hypochlorite solution, stir the reaction at room temperature for 3-4 h, and dry under vacuum to obtain crude product.

[0012] (2) Dissolve the crude product in methanol and mix it evenly with silica gel, then dry it and load it into a silica gel column. Use a solvent with a volume ratio of dichloromethane:methanol = 200:1 as the eluent to elute and collect the separated fractions.

[0013] (3) The fractions were monitored by thin-layer chromatography, and the fractions with the same Rf value were combined. The solvent was removed by rotary evaporation to obtain the purified compound P220.

[0014] Further, step (3) specifically involves using a solvent with a volume ratio of dichloromethane:methanol = 15:1 as the developing solvent, monitoring each fraction by thin-layer chromatography, merging all fractions with an Rf value of 0.44, concentrating by rotary evaporation to remove the solvent, and obtaining the purified compound P220.

[0015] Furthermore, in step (1), the available chlorine content in the sodium hypochlorite solution is ≥ 7%.

[0016] Further, in step (2), the obtained crude product is dissolved in methanol and mixed evenly with 100-200 mesh silica gel, with a mass ratio of crude product:silica gel = 1:(1-3).

[0017] Furthermore, in step (2), the silicone column is filled with 200-300 mesh silicone.

[0018] The present invention relates to the application of acetaminophen disinfection byproducts in the toxicity assessment of acetaminophen disinfection byproducts in the environment.

[0019] The application of acetaminophen disinfection byproducts provided by this invention in providing standardized samples for pollution control.

[0020] The beneficial effects of this invention are: This invention, by simulating the reaction conditions of acetaminophen and sodium hypochlorite, establishing a gradient elution column chromatography purification system, and combining high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-quadrupole-time-of-flight mass spectrometry), HPLC, carbon-13 NMR, hydrogen-1 NMR, and Fourier transform infrared spectroscopy, achieves the efficient preparation and structural identification of acetaminophen disinfection byproducts P186 and P220. This provides standardized samples and technical support for studying the formation mechanism of acetaminophen disinfection byproducts in the environment, toxicity assessment, and pollution control. It is of great significance for improving drug safety, protecting public health, and protecting the environment. This invention has the advantages of simple operation, high product purity, and good reproducibility, and is suitable for laboratory-scale and industrial production. Attached Figure Description

[0021] Figure 1 Flowchart for the synthesis of acetaminophen disinfection byproducts P186 and P220.

[0022] Figure 2 This is the high-resolution mass spectrum of compound P186.

[0023] Figure 3 For compound P186 1 H NMR results.

[0024] Figure 4 For compound P186 13 C NMR results.

[0025] Figure 5 This is the high-performance liquid chromatogram of compound P186.

[0026] Figure 6 This is the infrared spectrum of compound P186.

[0027] Figure 7 High-resolution mass spectrum of compound P220

[0028] Figure 8 For compound P220 1 H NMR results.

[0029] Figure 9 For compound P220 13 C NMR results.

[0030] Figure 10 This is the high-performance liquid chromatogram of compound P220.

[0031] Figure 11 This is the infrared spectrum of compound P220. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] Example 1: Acetaminophen disinfection byproduct—compound P186

[0034] I. The preparation method is as follows: Synthetic routes such as Figure 1 .

[0035] 1. Synthesis of crude extract of acetaminophen disinfection byproduct

[0036] Dissolve 3.3 g of acetaminophen in 100 mL of purified water, add 54.7 mL of sodium hypochlorite solution (the available chlorine content of sodium hypochlorite solution is 7%), the solution quickly turns from colorless to black, stir the reaction at room temperature for 3-4 h, place the reaction solution in a vacuum drying oven and dry at 50 °C to obtain a black solid, which is the crude product.

[0037] 2. Washing

[0038] The crude product was dissolved in methanol, and then 100-200 mesh silica gel was added at a mass ratio of crude product to silica gel of 1:2. After mixing evenly, the mixture was placed in a vacuum drying oven and dried at 50°C. Finally, the sample was loaded into a silica gel column (filled with 200-300 mesh silica gel) and eluted with a solvent of dichloromethane to methanol of 100:1 by volume. The separated fractions were collected.

[0039] 3. Purification

[0040] Using a solvent with a volume ratio of dichloromethane:methanol = 15:1 as the developing solvent, each fraction was monitored by thin-layer chromatography. All fractions with an Rf value of 0.37 were combined, concentrated by rotary evaporation, and the solvent was removed to obtain the purified compound, which was named compound P186.

[0041] II. Structural Confirmation

[0042] 1. Structural confirmation of the high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry system

[0043] The structure of the isolated compound P186 was confirmed by high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.

[0044] The parameters for the high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-QFMS) were set as follows: An Agilent 6530 QFMS system was used for mass spectrometry analysis, and samples were separated using an Agilent 1260 HPLC system in ESI(+) mode. The nebulizer flow rate was 8 L / min; nebulizer temperature was 350 °C; nebulizer pressure was 35 psig; capillary voltage was 3500 V; and the mass scan range was 50–1000 Da. Argon was used as the collision gas. The chromatographic column was an Agilent ZORBAX SB-C18 (4.6 mm × 250 mm, 5 µm). The mobile phase flow rate was set to 0.5 mL / min; and the column temperature was 30 °C. Gradient elution was performed using a 0.1% formic acid / water / methanol elution system. The elution process was as follows: within 10 min, the ratio of the 0.1% formic acid / water / methanol mobile phase linearly changed from 60 / 40 to 10 / 90.

[0045] Gradient elution was performed using 0.1% formic acid water (A) and methanol (B) as the elution system, with conditions shown in Table 1. The structure of the separated compound P186 was confirmed by high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-QPC-MS / MS), with gradient elution for 10 min yielding a spectrum with good resolution and peak shape. Figure 2 The image shows the primary mass spectrum of compound P186. The mass-to-nucleus ratio (m / z) of compound P186 is 186.0308, and its molecular formula is C8H8ClNO2. Its precise molecular weight is in good agreement with the theoretical value (error < 5 ppm).

[0046] Table 1. Elution conditions of mobile phase for high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.

[0047] 2. Nuclear magnetic resonance analysis

[0048] A Bruker Ascend™ 600MHz nuclear magnetic resonance spectrometer was used. The purified compound P186 was dried in a vacuum drying oven to avoid moisture interference. After drying for 24 h, compound P186 was dissolved in a deuterated solvent (DMSO-d6). After the sample was fully dissolved, it was transferred to an NMR tube for NMR analysis. The results are as follows: Figure 3 and Figure 4 The results showed: 1H NMR (600 MHz, DMSO-d6) δ 9.83 (d, J = 23.3 Hz, 2H, H-9& H-7), 7.69 (d, J = 2.5 Hz, 1H, H-3), 7.22 (dd, J = 8.8, 2.6 Hz, 1H, H-5), 6.89 (d, J =8.8 Hz, 1H, H-6), 1.99 (s, 3H, H-11). 13 C NMR (151 MHz, DMSO) δ 168.35 (C-10), 149.21 (C-1), 132.29 (C-4), 121.10 (C-2), 119.57 (C-3), 119.50 (C-5), 116.92 (C-6), 24.22 (C-11). 3. High-performance liquid chromatography analysis The purity of the isolated compound P186 was analyzed by high performance liquid chromatography.

[0049] The parameters of the high-performance liquid chromatograph (HPLC) were set as follows: a Shimadzu LC-2030Plus HPLC system was used, and the maximum absorption peak of the disinfection byproduct was detected at a wavelength of 254 nm. A Diamonsil C18(2) 5u (250 mm × 4.6 mm) column was selected for gradient separation, with a column temperature of 30 ℃ and a mobile phase of 0.1% formic acid / methanol. The elution process of compound P186 was as follows: within 20 min, the ratio of the mobile phase changed linearly from 95 / 5 to 1 / 99. The mobile phase elution conditions are shown in Table 2, and the results are as follows. Figure 5 .

[0050] The analysis results showed that compound P186 exhibited a significant characteristic absorption peak at a wavelength of 254 nm. Compound P186 had a retention time of 11.655 min, a symmetrical peak shape, good separation, and a purity of 97.946%.

[0051] Table 2 Elution conditions of mobile phase for P186 in high performance liquid chromatography

[0052] 4. Fourier transform infrared analysis

[0053] Take dried potassium bromide and a small amount of sample, mix them, grind them evenly with an agate mortar, then compress them into tablets, and use an IRAffinity-1 infrared spectrometer at 4000 cm⁻¹. -1 -400 cm -1 Compound P186 was scanned within the spectral range.

[0054] The infrared results of compound P186 are as follows: Figure 6 : 3178 cm -1 It is the stretching vibration of the phenolic hydroxyl group OH and the stretching vibration of NH; 2841 cm -1 It is the stretching vibration of CH; 1618 cm -1 It is a stretching vibration of C=O, 1598 cm. -1 It is a C=C skeletal vibration of the benzene ring; 1548 cm -1 It is the bending vibration of NH; 1419 cm -1 and 1363 cm -1 It is an in-plane curvature of CH; 1268 cm -1 1232 cm -1 1189 cm -1 and 1139 cm -1 It represents the symmetric and asymmetric stretching of CN and CO; 1047 cm -1 975 cm -1 875 cm -1 and 813 cm -1 It is the out-of-plane curvature of CH; 707 cm -1 605 cm -1 It is the stretching vibration of C-Cl.

[0055] In summary, the structure of compound P186 is as shown in formula (I), with the chemical formula C8H8ClNO2, and its chemical name is 3-chloro-4-hydroxyacetanilide. The physicochemical properties of compound P186 are: white powder, readily soluble in methanol.

[0056]

[0057] Example 2: Acetaminophen disinfection byproduct—compound P220

[0058] I. The preparation method is as follows: Synthetic routes such as Figure 1 .

[0059] 1. Synthesis of crude extract of acetaminophen disinfection byproduct

[0060] Dissolve 3.3 g of acetaminophen in 100 mL of purified water, add 54.7 mL of sodium hypochlorite solution (the available chlorine content of sodium hypochlorite solution is 7%), the solution quickly turns from colorless to black, stir the reaction at room temperature for 3-4 h, place the reaction solution in a vacuum drying oven and dry at 50 °C to obtain a black solid, which is the crude product.

[0061] 2. Washing

[0062] The crude product was dissolved in methanol, and then 100-200 mesh silica gel was added at a mass ratio of crude product to silica gel of 1:2. After mixing evenly, the mixture was placed in a vacuum drying oven and dried at 50°C. Finally, the sample was loaded into a silica gel column (filled with 200-300 mesh silica gel) and eluted with a solvent of dichloromethane to methanol of 200:1 by volume. The separated fractions were collected.

[0063] 3. Purification

[0064] Using a solvent with a volume ratio of dichloromethane:methanol = 15:1 as the developing solvent, each fraction was monitored by thin-layer chromatography. All fractions with an Rf value of 0.44 were combined, concentrated by rotary evaporation, and the solvent was removed to obtain the purified compound, which was named compound P220.

[0065] II. Structural Confirmation

[0066] 1. Structural confirmation of the high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry system

[0067] The structure of the isolated compound P220 was confirmed using high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.

[0068] The parameters for the high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-QFMS) were set as follows: An Agilent 6530 QFMS system was used for mass spectrometry analysis, and samples were separated using an Agilent 1260 HPLC system in ESI(+) mode. The nebulizer flow rate was 8 L / min; nebulizer temperature was 350 °C; nebulizer pressure was 35 psig; capillary voltage was 3500 V; and the mass scan range was 50-1000 Da. Argon was used as the collision gas. The column was an Agilent ZORBAX SB-C18 (4.6 mm × 250 mm, 5 µm). The mobile phase flow rate was set to 0.5 ml / min; and the column temperature was 30 °C. Gradient elution was performed using a 0.1% formic acid / water / methanol elution system. The elution process was as follows: within 10 min, the ratio of the 0.1% formic acid / water / methanol mobile phase linearly changed from 60 / 40 to 10 / 90.

[0069] Gradient elution was performed using 0.1% formic acid water (A) and methanol (B) as the elution system, with conditions shown in Table 3. The structure of the separated compound P220 was confirmed by high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-QPC-MS / MS), with gradient elution for 10 min yielding a spectrum with good resolution and peak shape. Figure 7 The image shows the first-order mass spectrum of compound P220. The mass-to-nucleus ratio (m / z) of compound P220 is 219.9920, and its molecular formula is C8H7Cl2NO2. Its precise molecular weight is in good agreement with the theoretical value (error < 5 ppm).

[0070] Table 3. Mobile phase elution conditions for high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry

[0071] 2. Nuclear magnetic resonance analysis

[0072] A Bruker Ascend™ 600MHz nuclear magnetic resonance spectrometer was used. The purified compound P220 was dried in a vacuum drying oven to avoid moisture interference. After drying for 24 h, compound P220 was dissolved in a deuterated solvent (DMSO-d6). After the sample was fully dissolved, it was transferred to an NMR tube for NMR analysis. The results are as follows: Figure 8 and Figure 9 The results showed: 1 H NMR (600 MHz, DMSO-d6) δ 9.97 (s, 1H, H-9), 9.81 (s, 1H, H-7), 7.58 (s, 2H, H-3& H-5), 2.01 (s, 3H, H-11). 13 C NMR (151 MHz, DMSO-d6) δ 168.75 (C-10), 145.08 (C-1), 132.92 (C-4), 122.66 (C-2& C-6), 119.43 (C-3& C-5), 24.32 (C-11). 3. High-performance liquid chromatography analysis The purity of the isolated compound P220 was analyzed by high performance liquid chromatography.

[0073] The parameters of the high-performance liquid chromatograph (HPLC) were set as follows: a Shimadzu LC-2030Plus HPLC system was used, and the maximum absorption peak of the disinfection byproduct was detected at a wavelength of 254 nm. A Diamonsil C18(2) 5u (250 mm × 4.6 mm) column was selected for gradient separation, with a column temperature of 30 ℃ and a mobile phase of 0.1% formic acid / methanol. The elution process of compound P220 was as follows: within 20 min, the ratio of the mobile phase changed linearly from 95 / 5 to 1 / 99. The mobile phase elution conditions are shown in Table 4, and the results are as follows. Figure 10 .

[0074] The analysis results showed that compound P220 exhibited a significant characteristic absorption peak at a wavelength of 254 nm. Compound P220 had a retention time of 14.078 min, a symmetrical peak shape, good separation, and a purity of 99.061%.

[0075] Table 4 Elution conditions of P220 mobile phase in high performance liquid chromatography

[0076] 4. Fourier transform infrared analysis

[0077] Take dried potassium bromide and a small amount of sample, mix them, grind them evenly with an agate mortar, then compress them into tablets, and use an IRAffinity-1 infrared spectrometer at 4000 cm⁻¹. -1 -400 cm -1 Compound P220 was scanned within the spectral range.

[0078] The infrared results of compound P220 are as follows Figure 11 The stretching vibrations of OH and NH appeared at 3319 cm. -1 Furthermore, the peak shape is clearly split; 2922 cm -1 2868 cm -1 It is a CH stretching vibration; 1662 cm -1 It is a stretching vibration of C=O, 1593 cm. -1 It is a C=C skeletal vibration of the benzene ring; 1541 cm -1 It is the bending vibration of NH; 1485 cm -1 1402 cm -1 It is an in-plane curvature of CH; 1284 cm -1 1222 cm -1 and 1161 cm -1 It is the symmetric and asymmetric stretching of CN and CO; 1020 cm -1 858 cm -1 and 804 cm -1It is the out-of-plane curvature of CH; 677 cm -1 582 cm -1 It is the stretching vibration of C-Cl.

[0079] In summary, the structure of compound P220 is as shown in formula (II), with the chemical formula C8H7Cl2NO2, and its chemical name is 3',5'-dichloro-4'-hydroxyacetanilide. The physicochemical properties of compound P220 are: white powder, readily soluble in methanol.

[0080]

Claims

1. A disinfection byproduct of acetaminophen, characterized in that, The acetaminophen disinfection byproducts are compound P186 with structural formula (I) and compound P220 with structural formula (II); and .

2. The method for preparing the acetaminophen disinfection byproduct according to claim 1, characterized in that, The preparation method of compound P186 includes the following steps: (1) Synthesis of crude extract of disinfection byproduct of acetaminophen: Acetaminophen was dissolved in purified water, sodium hypochlorite solution was added, and the mixture was stirred at room temperature for 3-4 h. The mixture was then dried under vacuum to obtain the crude product. (2) Dissolve the crude product in methanol and mix it evenly with silica gel, then dry it and load it into a silica gel column. Use a solvent with a volume ratio of dichloromethane:methanol = 100:1 as the eluent to elute and collect the separated fractions. (3) The fractions were monitored by thin-layer chromatography, and the fractions with the same Rf value were combined. The solvent was removed by rotary evaporation to obtain the purified compound P186.

3. The method for preparing the acetaminophen disinfection byproduct according to claim 2, characterized in that, Step (3) is as follows: a solvent with a volume ratio of dichloromethane:methanol = 15:1 is used as the developing solvent. Each fraction is monitored by thin-layer chromatography. All fractions with an Rf value of 0.37 are combined and concentrated by rotary evaporation to remove the solvent, thereby obtaining the purified compound P186.

4. The method for preparing the acetaminophen disinfection byproduct according to claim 1, characterized in that, The preparation method of compound P220 includes the following steps: (1) Synthesis of crude extract of disinfection byproduct of acetaminophen: Dissolve acetaminophen in purified water, add sodium hypochlorite solution, stir the reaction at room temperature for 3-4 h, and dry under vacuum to obtain crude product; (2) Dissolve the crude product in methanol and mix it evenly with silica gel, then dry it and load it into a silica gel column. Use a solvent with a volume ratio of dichloromethane:methanol = 200:1 as the eluent to elute and collect the separated streams. (3) The fractions were monitored by thin-layer chromatography, and the fractions with the same Rf value were combined. The solvent was removed by rotary evaporation to obtain the purified compound P220.

5. The method for preparing the acetaminophen disinfection byproduct according to claim 4, characterized in that, Step (3) is as follows: a solvent with a volume ratio of dichloromethane:methanol = 15:1 is used as the developing solvent. Each fraction is monitored by thin-layer chromatography. All fractions with an Rf value of 0.44 are combined. The solvent is removed after rotary evaporation concentration to obtain the purified compound P220.

6. The method for preparing the acetaminophen disinfection byproduct according to any one of claims 2-5, characterized in that, In step (1), the available chlorine content in the sodium hypochlorite solution is ≥ 7%.

7. The method for preparing the acetaminophen disinfection byproduct according to any one of claims 2-5, characterized in that, In step (2), the crude product is dissolved in methanol and mixed evenly with 100-200 mesh silica gel. The mass ratio of crude product to silica gel is 1:(1-3).

8. The method for preparing the acetaminophen disinfection byproduct according to any one of claims 2-5, characterized in that, In step (2), the silicone column is filled with 200-300 mesh silicone.

9. The application of the acetaminophen disinfection byproduct as described in claim 1 in the toxicity assessment of acetaminophen disinfection byproducts in the environment.

10. The application of the acetaminophen disinfection byproduct of claim 1 in providing standardized samples for pollution control.

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