A method for preparing calcium acetyltaurate and other acetyltaurate salts

Abstract

The invention discloses a method for preparing acetyltaurine calcium salt and other acetyltaurine salts, comprising the following steps: S1, dissolving taurine in deionized water and reacting with calcium hydroxide, filtering and concentrating the water to obtain taurine calcium salt; S2, dispersing taurine calcium salt in acetic acid and reacting with acetic anhydride, concentrating the acetic acid to obtain acetyltaurine calcium salt. S3, dissolving acetyltaurine calcium salt in deionized water and adding dropwise M n+ The cationic sulfate aqueous solution is filtered after calcium sulfate precipitation is precipitated, and a single post-treatment solvent is added to concentrate the water for crystallization, filtered and dried to obtain other acetyltaurate. The process method of the present invention can efficiently prepare acetyltaurate of various metal ions through sulfates of different metal ions through the same process route; and the process is simple and stable, the reaction conditions are relatively mild, the raw materials are all commercially available, cheap and easy to obtain, the yield is high, and it is conducive to large-scale industrial production.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and in particular to a method for preparing acetyltaurine calcium salt and other acetyltaurine salts. Background Art

[0002] Taurine is one of the common sulfur-containing amino acids in humans and animals. Taurine is widely distributed in various tissues and organs in the body. N-acetyltaurine is a derivative of taurine and a secondary metabolite in the human body. Studies have shown that acetyltaurine and its magnesium salt have important physiological functions in inhibiting food intake and resisting obesity, as well as preventing retinal damage. Since acetyltaurine salts have good water solubility, good stability, and easy absorption, they have broad application prospects.

[0003] The existing application of acetyltaurine is mainly concentrated on magnesium salt. In addition to magnesium salt, there are few literature reports on the application and preparation methods of other metal salts of acetyltaurine, and the process does not have universality and large-scale industrial production prospects. Therefore, it is necessary to propose a new method for simultaneously preparing multiple acetyltaurine metal salts to solve some of the above problems. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for preparing acetyltaurine calcium salt and other acetyltaurine salts in view of the deficiencies in the prior art.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] The present invention provides a method for preparing acetyltaurine calcium salt, and provides a method for preparing other acetyltaurine salts using the acetyltaurine calcium salt. Specifically, the acetyltaurine calcium salt prepared in the present invention comprises: acetyltaurine calcium monohydrate with one inherent water molecule, and the relative molecular weight (Molecular Weight) is about 390.44. Other acetyltaurate salts prepared include: acetyltaurate calcium monohydrate with one inherent water molecule, with a relative molecular weight of about 390.44; acetyltaurate lithium monohydrate with one inherent water molecule, with a relative molecular weight of about 191.13; acetyltaurate sodium monohydrate with one inherent water molecule, with a relative molecular weight of about 207.18; acetyltaurate potassium monohydrate with one inherent water molecule, with a relative molecular weight of about 223.29; acetyltaurate magnesium dihydrate with two inherent water molecules, with a relative molecular weight of about 392.69; acetyltaurate ferrous salt without inherent water molecules, with a relative molecular weight of about 388.20; acetyltaurate zinc salt without inherent water molecules, with a relative molecular weight of about 397.73. The reaction routes of acetyltaurate calcium salt and other acetyltaurate salts are shown in the attached figure.Figure 1 As shown in the figure, Ca(OH)2 is calcium hydroxide, Ac2O is acetic anhydride, and MSO4 refers to the sulfate corresponding to the metal ion. n+ is a cation, and n is an integer selected from 1, 2 or 3. The cation M n+ It can be any cation suitable for use in the disclosed method. Suitable cations include, but are not limited to, for example, Li + 、Na + , K + Mg 2+ , Fe 3+ / Fe 2 + 、Zn 2+ NH4 + In some embodiments, when M n+ When it is a divalent or trivalent cation, the balance M n+ The anion necessary for the charge of may include a mixture of acetyltaurate and another pharmaceutically acceptable anion. By way of example and not limitation, a compound suitable for the present invention may be acetyltaurate magnesium chloride.

[0007] The first aspect of the present invention provides a method for preparing acetyl taurine calcium salt, comprising the following steps:

[0008] S1, dissolving taurine in deionized water and reacting with calcium hydroxide, filtering and concentrating the water to obtain taurine calcium salt;

[0009] S2. Dispersing the taurine calcium salt obtained in step S1 in acetic acid and reacting with acetic anhydride, and concentrating the acetic acid to obtain acetyl taurine calcium salt.

[0010] Preferably, in step S1, the molar ratio of calcium hydroxide to taurine is 0.5:1 to 0.7:1; for example, it can be 0.5:1, 0.6:1, 0.7:1 or any value between them, and most preferably 0.5:1.

[0011] Preferably, the volume of deionized water used in step S1 is 3 to 10 times the weight of taurine, measured in mL by volume and g by weight, for example, 3, 5, 8, 10 times or any value therebetween, and most preferably 8 times.

[0012] Preferably, the reaction temperature of step S1 is 50-100°C, for example, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C or any value therebetween, most preferably 100°C.

[0013] Preferably, the molar ratio of acetic anhydride in step S2 to taurine in step S1 is 0.8:1 to 1.5:1; for example, it can be 0.8:1, 1.0:1, 1.2:1, 1.5:1 or any value between them, and most preferably is 1.0:1.

[0014] Preferably, the reaction temperature of step S2 is 10-60°C, for example, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C or any value therebetween, most preferably 50°C.

[0015] Preferably, the reaction time of step S2 is 0.5-2.0 h, for example, 0.5, 1.0, 1.5, 2.0 h or any value therebetween, most preferably 1.0 h.

[0016] Preferably, the volume of acetic acid used in step S2 is 3 to 10 times the weight of taurine in step 1, measured in mL by volume and g by weight; for example, it can be 3, 5, 8, 10 times or any value between them, and most preferably 5 times.

[0017] Preferably, the preparation method of acetyltaurine calcium salt comprises the following steps:

[0018] S1. Dissolve taurine in deionized water and react with calcium hydroxide at 50-100° C. with stirring until the product is a colorless clear liquid, keep warm and stir for 0.5-2 hours, and concentrate to dryness at 50-70° C. to obtain taurine calcium salt;

[0019] S2. Disperse the taurine calcium salt obtained in step S1 in acetic acid and react with acetic anhydride at 10-60° C. for 0.5-2.0 h, and concentrate to dryness at 50-70° C. to obtain acetyl taurine calcium salt.

[0020] The second aspect of the present invention provides a method for preparing acetyl taurate, wherein the acetyl taurate is other acetyl taurate than acetyl taurate calcium salt, and the method comprises the following steps:

[0021] The calcium salt of acetyl taurate as described above was dissolved in deionized water and added dropwise to M n+ A cationic sulfate aqueous solution is prepared, calcium sulfate is precipitated and then filtered, the water is concentrated and then a single post-treatment solvent is added for crystallization, and then filtered and dried to obtain acetyl taurate;

[0022] wherein n is an integer selected from 1, 2 or 3.

[0023] Preferably, M n+ For Li + 、Na + , K + Mg 2+, Fe 3+ , Fe 2+ 、Zn 2+ or NH4 + .

[0024] Preferably, the method for preparing acetyl taurate is characterized by comprising the following steps:

[0025] Add the above-mentioned calcium acetyl taurate salt into deionized water and stir until it is completely dissolved to obtain a calcium acetyl taurate salt solution; n+ The sulfate of the cation is dissolved in deionized water, and the resulting M n+ The cationic sulfate aqueous solution is added dropwise to the acetyl taurate calcium salt solution, the reaction is stirred for 0.5-2h, the precipitate is filtered and discarded, the filtrate is concentrated to dryness at 50-70°C, and then a single post-treatment solvent is added for crystallization, filtered, rinsed and dried to obtain acetyl taurate.

[0026] Preferably, M n+ The sulfate of the cation is any one of lithium sulfate, lithium sulfate monohydrate, sodium sulfate, sodium sulfate decahydrate, potassium sulfate, magnesium sulfate, magnesium sulfate heptahydrate, ferrous sulfate, ferrous sulfate heptahydrate, zinc sulfate, and zinc sulfate heptahydrate.

[0027] Preferably, the single post-treatment solvent is selected from ethanol, methanol, isopropanol, acetone, tetrahydrofuran, and most preferably ethanol.

[0028] Preferably, M n+ The molar ratio of the cationic sulfate to the calcium salt of acetyl taurate is 1.0:1 to 1.2:1; for example, it can be 1.0:1, 1.1:1, 1.2:1 or any value between them, and the most preferred ratio is 1.0:1.

[0029] Preferably, the volume of deionized water used to dissolve acetyl taurate calcium salt is 3 to 10 times the weight of acetyl taurate calcium salt, measured in mL by volume and g by weight, for example, 3, 5, 8, 10 times or any value in between, most preferably 5 times.

[0030] Preferably, the volume unit is mL and the weight unit is g. n+ The volume of the deionized water of the cationic sulfate is 3 to 10 times the weight of the calcium salt of acetyl taurate, for example, 3, 5, 8, 10 times or any value in between, and most preferably 3 times.

[0031] Preferably, the volume of the single post-treatment solvent, measured in mL by volume and g by weight, is 5 to 20 times the weight of the acetyl taurate calcium salt monohydrate in step S2, for example, 5, 10, 15, 20 times or any value between them, most preferably 10 times.

[0032] The beneficial effects of the present invention are:

[0033] The invention provides a preparation method of acetyltaurine calcium salt and other metal salts. The invention uses taurine which is cheap and easily available in large-scale industrial production as a raw material, firstly generates water-soluble taurine calcium salt with calcium hydroxide, then reacts with acetic anhydride in acetic acid to prepare acetyltaurine calcium salt product, and finally utilizes acetyltaurine calcium salt and sulfates of various metal ions to react and precipitate calcium sulfate to obtain other acetyltaurine salt products. The process method of the invention can efficiently prepare acetyltaurine salts of various metal ions through sulfates of different metal ions through the same process route; the process is simple and stable, the reaction conditions are relatively mild, the raw materials are all commercially available, cheap and easily available, the yield is high, and the large-scale industrial production is conducive. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The reaction route of the acetyltaurine calcium salt and other acetyltaurine salts of the present invention;

[0035] Figure 2 This is the NMR spectrum of the finished product of acetyltaurine calcium salt monohydrate prepared in Example 2;

[0036] Figure 3 This is the NMR spectrum of the finished product of acetyltaurine magnesium salt dihydrate prepared in Example 3;

[0037] Figure 4 This is the NMR spectrum of the finished product of acetyltaurine sodium salt monohydrate prepared in Example 5;

[0038] Figure 5 This is the NMR spectrum of the finished product of acetyl taurine zinc salt prepared in Example 8. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0040] It should be understood that terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0041] The test methods used in the following examples are conventional methods unless otherwise specified. The materials and reagents used in the following examples are all commercially available unless otherwise specified. In the following examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if the manufacturer is not specified, are all conventional products that can be purchased commercially.

[0042] Example 1

[0043] Preparation of taurine calcium salt:

[0044]

[0045] Add 1.2L of water to a 2L three-necked flask, then add taurine (150.0g, 1.20mol), stir and disperse evenly; then add calcium hydroxide (44.5g, 0.60mol) in batches, heat to 100°C, stir to react until dissolved into a colorless clear liquid, and keep stirring for 1h; transfer the reaction solution to a rotary evaporator, heat to 60°C, and concentrate to dryness under reduced pressure to obtain taurine calcium salt, which is a white powder to block solid with a wet weight of 189.5g.

[0046] Example 2

[0047] Preparation of acetyltaurate calcium salt monohydrate:

[0048]

[0049] Add 750 mL of acetic acid to a 2L three-necked flask, then add 189.5 g of the wet taurine calcium salt obtained in Example 1, and stir to disperse evenly; then add acetic anhydride (122.5 g, 1.20 mol), raise the temperature to 50° C., and keep stirring for 1.0 h; after TLC monitoring of the reaction is complete, transfer the reaction solution to a rotary evaporator, raise the temperature to 60° C., concentrate to dryness under reduced pressure, and then further blow dry to obtain 220.5 g of acetyl taurine calcium salt monohydrate in the form of white powder to block solid, with a yield of 94.1%.

[0050] After testing, the moisture content of the sample is 4.77% (the detection method is based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyltaurine calcium salt monohydrate is 4.6%; the calcium content of the sample is 10.03% (the detection method is based on the inductively coupled plasma mass spectrometry in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the calcium content of acetyltaurine calcium salt monohydrate is 10.30%; it can be determined that the obtained sample is indeed acetyltaurine calcium salt monohydrate.

[0051] The NMR spectrum of the finished product of acetyltaurine calcium salt monohydrate prepared in this example is as follows Figure 2 As shown, the NMR data are as follows:

[0052] 1 H NMR (400MHz, D2O): δ = 3.48 (t, J = 6.8Hz, 2H), 3.01 (t, J = 6.8Hz, 2H), 1.91 (s, 3H).

[0053] Example 3

[0054] Preparation of acetyltaurate magnesium salt dihydrate:

[0055]

[0056] Add 100 mL of water to a 500 mL three-necked flask, weigh 20.0 g (51.2 mmol) of acetyltaurine calcium salt monohydrate obtained in Example 2, add it, stir and dissolve; in addition, dissolve magnesium sulfate heptahydrate (12.6 g, 51.2 mmol) in 60 mL of water, then dropwise add it to the reaction system to precipitate a white solid precipitate; stir and react for 1 h after addition, filter the precipitate, the mother liquor is a colorless clear liquid, transfer it to a rotary evaporation bottle, heat to 60 ° C and concentrate under reduced pressure until there is no droplet, add 200 mL of anhydrous ethanol, precipitate a white solid, and stir and crystallize at room temperature for 4 h. Filter, rinse the wet product with 10 mL of ethanol twice, and dry it with air at 90 ° C to obtain 19.5 g of acetyltaurine magnesium salt dihydrate finished product, which is a white powder with a yield of 97.0%.

[0057] After testing, the moisture content of the sample was 9.05% (the detection method was based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyltaurine magnesium salt dihydrate was 9.2%; the magnesium content of the sample was 6.26% (the detection method was based on the inductively coupled plasma mass spectrometry method in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the magnesium content of acetyltaurine magnesium salt dihydrate was 6.18%; it can be determined that the obtained sample is indeed acetyltaurine magnesium salt dihydrate.

[0058] The NMR spectrum of the finished product of acetyltaurine magnesium salt dihydrate prepared in this example is as follows Figure 3 As shown, the NMR data are as follows:

[0059] 1 H NMR (400MHz, D2O): δ = 3.47 (t, J = 6.8Hz, 2H), 3.00 (t, J = 6.8Hz, 2H), 1.90 (s, 3H).

[0060] Example 4

[0061] Preparation of acetyltaurate lithium salt monohydrate:

[0062]

[0063] Add 100 mL of water to a 500 mL three-necked flask, weigh 20.0 g (51.2 mmol) of acetyl taurine calcium salt monohydrate obtained in Example 1, add it, stir and dissolve; in addition, dissolve lithium sulfate monohydrate (6.35 g, 51.2 mmol) in 60 mL of water, then dropwise add it to the reaction system to precipitate a white solid precipitate; after adding, stir and react for 1 hour, filter the precipitate, the mother liquor is a colorless clear liquid, transfer it to a rotary evaporation bottle, heat it to 60 ° C and concentrate it under reduced pressure until there is no droplet, add 200 mL of anhydrous ethanol, precipitate a white solid, and stir and crystallize it at room temperature for 4 hours. Filter, rinse the wet product with 10 mL of ethanol twice, and dry it with air at 90 ° C to obtain 17.2 g of acetyl taurine lithium salt monohydrate finished product, which is a white powder with a yield of 87.9%.

[0064] After testing, the moisture content of the sample was 9.55% (the detection method was based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyl taurate lithium monohydrate was 9.4%; the lithium content of the sample was 3.71% (the detection method was based on the inductively coupled plasma mass spectrometry method in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the lithium content of acetyl taurate lithium monohydrate was 3.60%; it can be determined that the obtained sample is indeed acetyl taurate lithium monohydrate.

[0065] Example 5

[0066] Preparation of acetyltaurate sodium salt monohydrate:

[0067]

[0068] Add 100 mL of water to a 500 mL three-necked flask, weigh 20.0 g (51.2 mmol) of acetyltaurine calcium salt monohydrate obtained in Example 1, add it, stir and dissolve; separately, dissolve sodium sulfate decahydrate (16.50 g, 51.2 mmol) in 60 mL of water, then dropwise add it to the reaction system to precipitate a white solid precipitate; after adding, stir and react for 1 hour, filter the precipitate, the mother liquor is a colorless clear liquid, transfer it to a rotary evaporation bottle, heat to 60 ° C and concentrate under reduced pressure until there is no droplet, add 200 mL of anhydrous ethanol, precipitate a white solid, stir and crystallize at room temperature for 4 hours. Filter, rinse the wet product with 10 mL of ethanol twice, and dry it with air at 90 ° C to obtain 18.7 g of acetyltaurine sodium salt monohydrate finished product, which is a white powder with a yield of 88.1%.

[0069] After testing, the moisture content of the sample was 9.21% (the detection method was based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyl taurate sodium monohydrate was 8.7%; the sodium content of the sample was 10.85% (the detection method was based on the inductively coupled plasma mass spectrometry method in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the sodium content of acetyl taurate sodium monohydrate was 11.10%; it can be determined that the obtained sample is indeed acetyl taurate sodium monohydrate.

[0070] The NMR spectrum of the finished product of acetyltaurine sodium salt monohydrate prepared in this example is as follows Figure 4 As shown, the NMR data are as follows:

[0071] 1H NMR (400MHz, D2O) δ3.50 (t, J = 6.8 Hz, 2H), 3.03 (t, J = 6.8 Hz, 2H), 1.94 (s, 3H).

[0072] Example 6

[0073] Preparation of acetyltaurine potassium salt monohydrate:

[0074]

[0075] Add 100 mL of water to a 500 mL three-necked flask, weigh 20.0 g (51.2 mmol) of acetyl taurine calcium salt monohydrate obtained in Example 1, add it, stir and dissolve; in addition, dissolve potassium sulfate (8.92 g, 51.2 mmol) in 60 mL of water, then drop it into the reaction system to precipitate a white solid precipitate; stir and react for 1 h after adding, filter the precipitate, the mother liquor is a colorless clear liquid, transfer it to a rotary evaporation bottle, heat it to 60 ° C and concentrate it under reduced pressure until there is no droplet, add 200 mL of anhydrous ethanol, precipitate a white solid, stir and crystallize at room temperature for 4 h. Filter, rinse the wet product with 10 mL of ethanol twice, and dry it with air at 90 ° C to obtain 16.9 g of acetyl taurine potassium salt monohydrate finished product, which is a white powder with a yield of 73.9%.

[0076] After testing, the moisture content of the sample was 7.87% (the detection method was based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyltaurine potassium monohydrate was 8.1%; the potassium content of the sample was 18.22% (the detection method was based on the inductively coupled plasma mass spectrometry method in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the potassium content of acetyltaurine potassium monohydrate was 17.50%; it can be determined that the obtained sample is indeed acetyltaurine potassium monohydrate.

[0077] Example 7

[0078] Preparation of acetyl taurate ferrous salt:

[0079]

[0080] Add 100 mL of water to a 500 mL three-necked flask, weigh 20.0 g (51.2 mmol) of acetyltaurine calcium salt monohydrate obtained in Example 1, add it, stir and dissolve; separately, dissolve ferrous sulfate heptahydrate (14.23 g, 51.2 mmol) in 60 mL of water, then dropwise add it to the reaction system to precipitate a white solid precipitate; after adding, stir and react for 1 h, filter the precipitate, the mother liquor is a light green clear liquid, transfer it to a rotary evaporation bottle, heat to 60 ° C and concentrate under reduced pressure until there is no droplet, add 200 mL of anhydrous ethanol, precipitate a dark green solid, stir and crystallize at room temperature for 4 h. Filter, rinse the wet product with 10 mL of ethanol twice, and dry it with air at 90 ° C to obtain 18.3 g of acetyltaurine ferrous salt finished product, which is a dark green powder with a yield of 92.1%.

[0081] After testing, the moisture content of the sample is 0.51% (the detection method is based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyltaurine ferrous salt is 0%; the iron content of the sample is 14.14% (the detection method is based on the inductively coupled plasma mass spectrometry method in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the iron content of acetyltaurine ferrous salt is 14.40%; it can be determined that the obtained sample is indeed acetyltaurine ferrous salt.

[0082] Example 8

[0083] Preparation of acetyl taurate zinc salt:

[0084]

[0085] Add 50 mL of water to a 250 mL three-necked flask, weigh 10.0 g (25.6 mmol) of acetyltaurine calcium salt monohydrate obtained in Example 1, add it, stir and dissolve; separately, dissolve zinc sulfate heptahydrate (7.36 g, 25.6 mmol) in 30 mL of water, then dropwise add it to the reaction system to precipitate a white solid precipitate; after adding, stir and react for 1 h, filter the precipitate, the mother liquor is a colorless clear liquid, transfer it to a rotary evaporation bottle, heat to 60 ° C and concentrate under reduced pressure until there is no droplet, add 100 mL of anhydrous ethanol, precipitate a white solid, stir and crystallize at room temperature for 4 h. Filter, rinse the wet product with 10 mL of ethanol twice, and dry it with air at 90 ° C to obtain 8.75 g of acetyltaurine zinc salt finished product, which is a white powder with a yield of 86.0%.

[0086] After testing, the moisture content of the sample is 0.42% (the detection method is based on the water determination method (Karl Fischer method) in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the moisture content of acetyltaurine zinc salt is 0%; the zinc content of the sample is 15.87% (the detection method is based on the inductively coupled plasma mass spectrometry method in Part IV of the 2020 edition of the Chinese Pharmacopoeia), and the theoretical value of the zinc content of acetyltaurine zinc salt is 16.40%; it can be determined that the obtained sample is indeed acetyltaurine zinc salt.

[0087] The NMR spectrum of the finished product of acetyltaurine zinc salt prepared in this example is as follows Figure 5 As shown, the NMR data are as follows:

[0088] 1H NMR (400MHz, D2O) δ3.42 (t, J = 6.8 Hz, 2H), 2.95 (t, J = 6.8 Hz, 2H), 1.85 (s, 3H).

[0089] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A method for preparing acetyltaurine calcium salt, characterized in that: The following steps are involved: S1, dissolving taurine in deionized water and reacting with calcium hydroxide, filtering and concentrating the water to obtain taurine calcium salt; S2. Dispersing the taurine calcium salt obtained in step S1 in acetic acid and reacting with acetic anhydride, and concentrating the acetic acid to obtain acetyl taurine calcium salt.

2. The method for preparing acetyltaurine calcium salt according to claim 1, characterized in that: In step S1, the molar ratio of calcium hydroxide to taurine is 0.5:1 to 0.7:1; The volume of the deionized water used in step S1 is 3 to 10 times the weight of taurine, with the volume unit being mL and the weight unit being g.

3. The method for preparing acetyltaurine calcium salt according to claim 1, characterized in that: The molar ratio of acetic anhydride in step S2 to taurine in step S1 is 0.8:1 to 1.5:1; The volume of acetic acid used in step S2 is 3 to 10 times the weight of taurine in step 1, with volume in mL and weight in g.

4. The method for preparing acetyltaurine calcium salt according to claim 1, characterized in that: The following steps are involved: S1. Dissolve taurine in deionized water and react with calcium hydroxide at 50-100° C. with stirring until the product is a colorless clear liquid, keep warm and stir for 0.5-2 hours, and concentrate to dryness at 50-70° C. to obtain taurine calcium salt; S2. Disperse the taurine calcium salt obtained in step S1 in acetic acid and react with acetic anhydride at 10-60° C. for 0.5-2.0 h, and concentrate to dryness at 50-70° C. to obtain acetyl taurine calcium salt.

5. A method for preparing acetyl taurate, wherein the acetyl taurate is other acetyl taurate than acetyl taurate calcium salt, characterized in that: The method comprises the following steps: The calcium salt of acetyl taurate according to any one of claims 1 to 4 is dissolved in deionized water and added dropwise to M n+ A cationic sulfate aqueous solution is prepared, calcium sulfate is precipitated and then filtered, the water is concentrated and then a single post-treatment solvent is added for crystallization, and then filtered and dried to obtain acetyl taurate; wherein n is an integer selected from 1, 2 or 3.

6. The method for preparing acetyl taurate according to claim 5, characterized in that: M n+ For Li + 、Na + , K + Mg 2+ , Fe 3+ , Fe 2+ 、Zn 2+ or NH4 + .

7. The method for preparing acetyl taurate according to claim 6, characterized in that: The following steps are involved: The acetyl taurate calcium salt according to any one of claims 1 to 4 is added to deionized water and stirred until completely dissolved to obtain an acetyl taurate calcium salt solution; n+ The sulfate of the cation is dissolved in deionized water, and the resulting M n+ The cationic sulfate aqueous solution is added dropwise to the acetyl taurate calcium salt solution, the reaction is stirred for 0.5-2h, the precipitate is filtered and discarded, the filtrate is concentrated to dryness at 50-70°C, and then a single post-treatment solvent is added for crystallization, filtered, rinsed and dried to obtain acetyl taurate.

8. The method for preparing acetyl taurate according to claim 7, characterized in that: M n+ The sulfate of the cation is any one of lithium sulfate, lithium sulfate monohydrate, sodium sulfate, sodium sulfate decahydrate, potassium sulfate, magnesium sulfate, magnesium sulfate heptahydrate, ferrous sulfate, ferrous sulfate heptahydrate, zinc sulfate, and zinc sulfate heptahydrate.

9. The method for preparing acetyl taurate according to claim 7, characterized in that: The single post-treatment solvent is selected from one of ethanol, methanol, isopropanol, acetone and tetrahydrofuran.

10. The method for preparing acetyl taurate according to claim 7, characterized in that: M n+ The molar ratio of the cationic sulfate to the calcium salt of acetyltaurine is 1.0:1 to 1.2:1; The volume unit is mL and the weight unit is g: The volume of deionized water used to dissolve acetyl taurine calcium salt is 3 to 10 times the weight of acetyl taurine calcium salt. n+ The volume of the deionized water of the cationic sulfate is 3 to 10 times the weight of acetyl taurate calcium salt, and the volume of the single post-treatment solvent is 5 to 20 times the weight of acetyl taurate calcium salt monohydrate in step S2.

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