A process for the preparation of milorine tartrate

Abstract

This invention, entitled "A Method for Preparing Milobalin Benzylsulfonic Acid," belongs to the field of organic synthesis technology. The technical problem to be solved is to improve the yield and purity of Milobalin Benzylsulfonic Acid, while ensuring convenient, environmentally friendly, and safe operation. The key technical points are: a method for preparing Milobalin Benzylsulfonic Acid, comprising the following steps: S1, using Formula 1 as a raw material, an esterification reaction is carried out to obtain Formula 2; S2, using Formula 1 as a raw material, a TL100L lipase reaction is used to obtain Formula 3; or using Formula 2 as a raw material, a CALB lipase hydrolysis is used to obtain Formula 3; S3, using Formula 3 as a raw material, an ammonolysis reaction is carried out under the action of a catalyst to obtain Formula 4; S4, using Formula 4 as a raw material, a Hoffmann reaction is carried out to obtain Formula 5; S5, using Formula 5 as a raw material, a salt-forming reaction is carried out with benzylsulfonic acid to obtain the final product.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, specifically relating to a method for preparing milobalin benzylsulfonic acid. Background Technology

[0002] Milobalin besylate is mainly used to treat diabetic peripheral neuropathy, postherpetic neuralgia, and fibromyalgia. It has advantages such as high safety and good tolerability, and is developing into a world-class drug for treating neuralgia, with broad market prospects. The structural formula of milobalin besylate is as follows:

[0003] .

[0004] The currently disclosed methods for preparing milobalin besylate mainly include the following: Relevant patent application documents retrieved: The publication country is China, publication number CN101878193A, publication date July 9, 2014. This document discloses a method using (1R,5S)-3-ethyl-bicyclo[3.2.0]heptane-3-en-6-one as the starting material, which is reacted with HWE and then reacted with nitromethane to generate an intermediate. This intermediate is then subjected to nitro reduction, chiral resolution, and detert-butylation to finally form a salt to obtain milobalin benzenesulfonic acid. However, this route generates double bond isomers on the five-membered ring during detert-butylation, which are difficult to remove.

[0005] To avoid the problem of difficult removal of the aforementioned double bond isomeric impurities, this paper further optimizes the second-generation synthetic route. By first generating an intermediate with nitromethane, then removing the tert-butyl group, then resolving and reducing, and finally forming a salt to obtain milobalin benzenesulfonic acid, the generation of double bond isomeric impurities is avoided.

[0006] The synthetic routes for the two reactions mentioned above are as follows:

[0007] This synthetic route is difficult to operate, results in significant product loss, and is costly due to the use of chemical chiral resolution.

[0008] Another publication, published in China (CN121135591A, December 16, 2025), discloses a method using a compound of formula III, generated by the HWE reaction of (1R,5S)-3-ethyl-bicyclo[3.2.0]heptane-3-en-6-one with diethyl malonate, as a starting material. Under the action of a strong organic base, the compound of formula III is reacted with acetonitrile in a nonpolar organic solvent at a low temperature below -50°C to obtain an intermediate product. Under alkaline conditions, the intermediate product undergoes oxidation and hydrolysis under the action of an oxidant. After the reaction, it is acidified to obtain another intermediate product, which is then subjected to a high-temperature decarboxylation reaction in an aprotic solvent to obtain compound of formula VI. Compound of formula VI is then subjected to a Hoffmann degradation reaction to obtain compound of formula I, milobalin, or a milobalin acid salt. The above synthetic route is as follows:

[0009] This synthetic route uses Michael addition, which requires reaction at ultra-low temperatures and is subject to harsh reaction conditions. It also uses an oxidant for oxidation, which carries certain risks of flammability and explosion. Furthermore, it requires high-temperature decarboxylation, which is subject to harsh reaction conditions and is difficult to operate.

[0010] The prior art represented by the aforementioned documents has at least the following unresolved technical problems or defects: The synthetic routes described in the aforementioned patent documents either involve chiral resolution, resulting in low yields and difficult recovery; or involve ultra-high temperature or ultra-low temperature reactions, which are difficult to operate, have high risk factors, and produce wastewater that is environmentally unfriendly.

[0011] Therefore, there is an urgent need in the field to provide a method for preparing milobalin benzylsulfonic acid that is convenient to operate, environmentally friendly and safe, does not require chiral separation, and has higher yield and purity. Summary of the Invention

[0012] The purpose of this invention is to provide: A method for preparing milobalin benzylsulfonic acid, and related technologies, to solve technical problems such as improving the yield and purity of milobalin benzylsulfonic acid, and ensuring convenient, green, environmentally friendly and safe operation, or a combination thereof.

[0013] Terminology Explanation: Unless otherwise defined, all technical terms in this invention have the same meanings as commonly understood by one of ordinary skill in the art to which the subject matter pertains. Unless otherwise stated, all patents, patent inventions, and disclosures referenced in this invention are incorporated herein by reference in their entirety. If multiple definitions exist for terms in this invention, the definitions in this chapter shall prevail.

[0014] It should be understood that the above brief description and the following detailed description are exemplary and for illustrative purposes only, and do not limit the subject matter of the invention in any way. In this invention, the singular is used in conjunction with the plural unless otherwise specifically stated. It should also be noted that, unless otherwise stated, the use of “or” or “or” means “and / or”. Furthermore, the use of the term “comprising” and other forms such as “including,” “containing,” and “contains” are not limiting.

[0015] Definitions of standard chemical terms can be found in the reference "Basic Organic Chemistry (Volumes 1 & 2), Higher Education Press, June 2005, 3rd Edition".

[0016] Unless otherwise stated, conventional methods within the scope of the art, such as purity testing, shall be used.

[0017] Unless specifically defined, the use of various commercially available products in this invention employs standard techniques. For example, it may be carried out using the manufacturer's instructions for use with the reagent kit, or in accordance with methods known in the art or the description of this invention. The techniques and methods described herein can generally be implemented according to conventional methods well known in the art, based on the descriptions in the various summary and more specific documents cited and discussed in this specification.

[0018] As used herein, the term "alkyl" refers to both divalent and polyvalent residues. For example, whenever appropriate, the term "alkyl" includes "alkylene," for instance, when the formula indicates that the alkyl group is divalent, or when a substituent is linked to form a ring. Examples of alkyl residues include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, sec-butyl, and, for example, n-pentyl, n-hexyl, n-heptyl, and analogs and isomers of n-octyl. Where the alkyl group is optionally substituted with one or more substituents, the one or more is typically 1, 2, 3, 4, or 5, and 1, 2, 3, or 4, and 1, 2, or 3, and 1 or 2, or 1, wherein the multiple substituents are chosen independently. Unless otherwise indicated, it should be understood that any substitution of the alkyl group or the alkyl group substituted on another part is linked at any available atom to provide a stable compound.

[0019] In a first aspect, the present invention provides: A method for preparing milobalin benzylsulfonic acid includes the following steps: S1. Using Formula 1 as raw material, Formula 2 is obtained through esterification reaction; S2. Using Formula 1 as raw material, Formula 3 is obtained by reaction with TL100L lipase; or using Formula 2 as raw material, Formula 3 is obtained by hydrolysis with CALB lipase. S3. Using Formula 3 as raw material, Formula 4 is obtained through ammonolysis under the action of a catalyst; S4. Using Formula 4 as raw material, Formula 5 is obtained through the Hoffmann reaction; S5. Using Formula 5 as a raw material, react with benzenesulfonic acid to form a salt, and the product is obtained. The synthesis route is as follows: .

[0020] Includes: the R group in Formula 2 and Formula 3; reaction conditions for steps S1-S4, etc.

[0021] In this context, "the R group in Formula 2 and Formula 3" is selected from C1-C4 alkyl groups.

[0022] Among them, the R group in Formula 2 and Formula 3 is preferably methyl, ethyl, propyl or butyl.

[0023] Among them, the R group in Formula 2 and Formula 3 is further preferably methyl or ethyl.

[0024] In step S1, "the esterification reaction process" includes: first mixing Formula 1 with an alcohol, and then adding an esterification reagent to carry out the esterification reaction.

[0025] It includes: alcohol; esterification reagent; Formula 1, mass ratio of alcohol to esterification reagent, etc.

[0026] The "alcohol" is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol and isobutanol.

[0027] The preferred "alcohol" is: alcohol, ethanol, propanol, isopropanol, butanol, or isobutanol.

[0028] The "alcohol" is further preferably methanol or ethanol.

[0029] The "esterification reagent" is selected from sulfuric acid or thionyl chloride.

[0030] The preferred "esterification reagent" is sulfuric acid.

[0031] Wherein, “Formula 1, mass ratio of alcohol to esterifying reagent” is selected from any value or range between 1:4:0.07 and 0.09.

[0032] The preferred mass ratio of "Formula 1, alcohol to esterification reagent" is 1:4:0.07, 1:4:0.08, 1:4:0.09 or any two of them.

[0033] The preferred ratio of "Formula 1, alcohol to esterification reagent" is any value or range between 1:4:0.08 and 0.09.

[0034] The "mixing temperature" is selected from any value or range between 25℃ and 35℃.

[0035] The preferred "mixing temperature" is 25°C, 30°C, 35°C, or any two of these temperatures.

[0036] The "mixing temperature" is selected from any value or range between 25℃ and 30℃.

[0037] The preferred "mixing temperature" is 25°C.

[0038] The "temperature of esterification reaction" is any value or range between 50℃ and 70℃, and the "time of esterification reaction" is any value or range between 10 and 12 hours.

[0039] The preferred temperature for the esterification reaction is 50℃, 55℃, 60℃, 65℃, 70℃ or any two of these, and the preferred time for the esterification reaction is 10h, 11h, 12h or any two of these.

[0040] The temperature of the "esterification reaction" is further preferably 50℃, 55℃, 60℃, 65℃, 70℃ or any two of them, and the time of the "esterification reaction" is further preferably 10h, 11h, 12h or any two of them.

[0041] The temperature of the "esterification reaction" is further preferably any value or range between 55℃ and 60℃, and the time of the "esterification reaction" is further preferably any value or range between 10h and 11h.

[0042] After the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is first adjusted to 6-7, and then distilled under reduced pressure; then toluene is added, the pH is adjusted to 8-9, and the liquid-liquid phase and organic phase are separated and concentrated.

[0043] In step S2, the enzyme concentration of "TL100L lipase" is 15-100 g / L, and the enzyme activity is not less than 5000 L U / g.

[0044] In step S2, "the reaction process" includes: dissolving compound formula 1 in buffer and alcohol reagent, and then reacting it with TL100 enzyme.

[0045] Includes: buffer solution; alcohol reagent; formula 1, the mass ratio of buffer solution, alcohol reagent and TL100 enzyme, etc.

[0046] Among them, "buffer solution" refers to potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer.

[0047] Among them, "alcohol reagents" refers to methanol or ethanol.

[0048] The mass ratio of Formula 1, buffer solution, alcohol reagent and TL100 enzyme is any value or range between 20:100-150:10-20:3-5.

[0049] The preferred mass ratio of Formula 1, buffer solution, alcohol reagent and TL100 enzyme is 20:100:10:3.

[0050] The "reaction temperature" is any value or range between 0℃ and 30℃, the "reaction time" is any value or range between 24 and 60 hours, and the "reaction pH" is any value or range between 7.5 and 8.0.

[0051] The preferred "reaction temperature" is 0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃ or any two of these, and the preferred "reaction time" is 24h, 30h, 35h, 40h, 50h, 55h, 60h or any two of these.

[0052] The "reaction temperature" is further preferably any value or range between 0℃ and 10℃, and the "reaction time" is any value or range between 24 and 50h.

[0053] In step S2, the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity is not less than 5000 L U / g.

[0054] In step S2, "the hydrolysis process" includes: dissolving Formula 2 in a buffer solution, and then adding CALB lipase to carry out the hydrolysis reaction.

[0055] Includes: buffer solution; Formula 2, mass ratio of buffer solution to CALB enzyme; hydrolysis conditions, etc. Among them, "buffer solution" refers to potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer.

[0056] The preferred "buffer solution" is potassium dihydrogen phosphate buffer solution.

[0057] The mass ratio of Formula 2, buffer solution and CALB enzyme is any value or range between 10:20 and 60:1-3.

[0058] The preferred mass ratio of Formula 2, buffer solution, and CALB enzyme is 10:50:1.

[0059] The "hydrolysis temperature" is any value or range between 0℃ and 30℃, the "hydrolysis time" is any value or range between 24 and 60 hours, and the "hydrolysis pH" is any value or range between 7.6 and 8.2.

[0060] The "hydrolysis temperature" is defined as 0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃ or any two of these ranges; the "hydrolysis time" is defined as 24h, 30h, 36h, 42h, 48h, 54h, 60h or any two of these ranges; and the "hydrolysis pH" is defined as 7.6, 8, 8.2 or any two of these ranges.

[0061] The preferred "hydrolysis temperature" is any value or range between 5℃ and 15℃, and the preferred "hydrolysis time" is any value or range between 24h and 48h.

[0062] In step S2, post-treatment is performed after the reaction and after the hydrolysis. The post-treatment includes: first adjusting the pH to 1-1.5, then heating to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, and filtering; finally separating the phases, extracting the aqueous phase with ethyl acetate, combining the organic phases and concentrating under reduced pressure.

[0063] In step S3, the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate.

[0064] The catalyst is preferably calcium chloride.

[0065] The ammonia source for the ammonolysis reaction is: ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride.

[0066] The preferred ammonia source for the ammonolysis reaction is methanol-ammonia.

[0067] Formula 3: The mass ratio of catalyst to ammonia source is any value or range between 5:2, 5:8, and 10.

[0068] In step S3, the "temperature of the ammonolysis reaction" is any value or range between 35℃ and 75℃, the "time of the ammonolysis reaction" is any value or range between 6 and 12h, and the "pressure of the ammonolysis reaction" is any value or range between 0.5 and 1.0MPa.

[0069] After the ammonolysis reaction is completed, the temperature needs to be lowered to 20℃-35℃ and concentrated under reduced pressure; then the temperature is raised to 35℃-45℃ and methanol and water are added to adjust the pH to 1-2; finally, the temperature is lowered to 0℃-5℃ to crystallize, filter and dry.

[0070] In step S4, "the process of the Hoffmann reaction" includes: first mixing the alkaline solution and water, then adding Formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining the product.

[0071] Includes: alkaline solution; degradation reagent; Formula 4, mass ratio of degradation reagent, alkaline solution and water, etc.

[0072] Among them, "alkali solution" refers to a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%.

[0073] The preferred "alkali solution" is a sodium hydroxide solution with a mass fraction of 25-35%.

[0074] The "degradation reagent" is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite.

[0075] The preferred "degradation reagent" is sodium hypochlorite.

[0076] The "mass fraction of degradation reagent" is any value or range between 5% and 15%.

[0077] Among them, "the mass ratio of Formula 4, degradation reagent, alkali solution and water" is any value or range between 50:150-200:25-30:20-30.

[0078] The "mixing temperature" is any value or range between -1℃ and 1℃.

[0079] The "stirring temperature" is any value or range between -5℃ and 5℃, and the "stirring time" is any value or range between 20 and 40 minutes.

[0080] The reaction conditions for adding the degradation reagent are as follows: first react at -5℃ to -5℃ for 1-2 hours, then react at 30℃ to 40℃ for 3-5 hours; after the Hoffmann reaction is completed, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5 to 6.5, crystallization performed, filtered and dried.

[0081] In step S5, "the process of salt formation reaction" includes: in an organic solvent, first mix Formula 5 with water, cool to 15-25°C, and then react with benzenesulfonic acid to form a salt, thus obtaining the product.

[0082] Includes: organic solvent; Formula 5, mass ratio of water, organic solvent and benzenesulfonic acid; conditions for salt formation reaction, etc.

[0083] The "organic solvent" refers to methanol or ethanol.

[0084] The mass ratio of "Formula 5, water, organic solvent and benzenesulfonic acid" is any value or range between 30:1-5:100-500:11.4-45.

[0085] The salt formation reaction takes 1-2 hours. After the salt formation reaction is completed, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours to allow crystallization, followed by filtration and drying.

[0086] Based on further solutions to the technical problems of the present invention, or simultaneous solutions to multiple technical problems, the preferred solution in the technical solution provided in the first aspect of the present invention includes: The first preferred embodiment: the R groups in both Formula 2 and Formula 3 are C1-C4 alkyl groups. This technical solution, while addressing the technical problem of "improving the yield and purity of milobalin benzylsulfonic acid," further solves the technical problems of "convenient operation, green environmental protection, and safety."

[0087] The second preferred embodiment: In step S1, the esterification reaction process includes: first mixing Formula 1 with an alcohol, and then adding an esterification reagent to carry out the esterification reaction. This technical solution not only solves the technical problem of "improving the yield and purity of milobalin benzyl sulfonate", but also further solves the technical problems of "convenient operation, green environmental protection and safety".

[0088] The third preferred embodiment: the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol; the esterification reagent is sulfuric acid or thionyl chloride. This technical solution, while addressing the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further solves the technical problems of "convenient operation, green environmental protection, and safety."

[0089] The fourth preferred embodiment: the mass ratio of the alcohol to the esterification reagent in Formula 1 is 1:4:0.07-0.09. This technical solution, in addition to solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further addresses the technical issues of "convenient operation, environmental friendliness, and safety."

[0090] The fifth preferred embodiment: the mixing temperature is 25℃-35℃; the esterification reaction temperature is 50℃-70℃, and the esterification reaction time is 10-12 hours. This technical solution, while addressing the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further solves the technical problems of "convenient operation, green environmental protection, and safety."

[0091] The sixth preferred option involves cooling the temperature to 20°C-35°C after the esterification reaction, adjusting the pH to 6-7, performing vacuum distillation, adding toluene, adjusting the pH to 8-9, separating the liquid phase, and concentrating the organic phase. This technical solution, while addressing the technical issues of "improving the yield and purity of milobalin benzyl sulfonate," further addresses the technical problems of "convenient operation, environmental friendliness, and safety."

[0092] The seventh preferred embodiment: In step S2, the concentration of the TL100L lipase solution is 15-100 g / L, and the enzyme activity of the TL100L lipase is not less than 5000 U / g. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin besylate," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0093] The eighth preferred embodiment: In step S2, the reaction process includes: dissolving compound formula 1 in buffer solution and alcohol reagent, and then reacting it with TL100 enzyme. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin besylate", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0094] The ninth preferred embodiment: the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer; the alcohol reagent is methanol or ethanol; the mass ratio of Formula 1, the buffer solution, the alcohol reagent, and the TL100 enzyme is 20:100-150:10-20:3-5. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin besylate," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0095] The tenth preferred embodiment: In step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60 h, and the reaction pH is 7.5-8.0. This technical solution, in addition to solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0096] Eleventh preferred embodiment: In step S2, the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin besylate", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0097] The twelfth preferred embodiment: In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution, and then adding CALB lipase for hydrolysis. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin besylate", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0098] The thirteenth preferred embodiment: the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer; the mass ratio of the buffer solution and CALB enzyme in Formula 2 is 10:20-60:1-3. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin besylate," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0099] The fourteenth preferred embodiment: In step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.2. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0100] The fifteenth preferred embodiment: In step S2, post-treatment is performed after the reaction and hydrolysis are completed. The post-treatment includes: first adjusting the pH to 1-1.5, then heating to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, followed by filtration; finally, separating the phases, extracting the aqueous phase with ethyl acetate, combining the organic phases, and concentrating under reduced pressure. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0101] The sixteenth preferred embodiment: In step S3, the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate; the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride; the mass ratio of the catalyst and the ammonia source in Formula 3 is 5:2-5:8-10. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin benzylsulfonic acid," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0102] The seventeenth preferred embodiment: In step S3, the ammonolysis reaction temperature is 35℃-75℃, the reaction time is 6-12 hours, and the pressure is 0.5-10.0 MPa. After the ammonolysis reaction, the temperature needs to be lowered to 20℃-35℃ for reduced pressure concentration; then the temperature is raised to 35℃-45℃, methanol and water are added, and the pH is adjusted to 1-2; finally, the temperature is lowered to 0℃-5℃ for crystallization, filtration, and drying. This technical solution, in addition to solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0103] The eighteenth preferred embodiment: In step S4, the Hoffmann reaction process includes: first mixing the alkaline solution and water, then adding Formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining the product. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin benzylsulfonic acid", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0104] The nineteenth preferred embodiment: the alkaline solution is a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%; the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite; the mass fraction of the degradation reagent is 5-15%; the mass ratio of Formula 4, degradation reagent, alkaline solution, and water is 50:150-200:25-30:20-30. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further addresses the technical problems of "convenient operation, green environmental protection, and safety."

[0105] The twentieth preferred embodiment: the mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 minutes; the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1-2 hours, then reacting at 30℃ to 40℃ for 3-5 hours; after the Hoffmann reaction, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5-6.5, crystallization performed, filtered, and dried. This technical solution, while solving the technical problem of "improving the yield and purity of milobalin benzyl sulfonate," further addresses the technical issues of "convenient operation, green environmental protection, and safety."

[0106] The twenty-first preferred embodiment: In step S5, the salt-forming reaction process includes: first mixing Formula 5 with water in an organic solvent, cooling to 15-25℃, and then reacting with benzenesulfonic acid to form a salt, thereby obtaining the product. This technical solution, while solving the technical problem of "improving the yield and purity of benzenesulfonic acid milobalin", further solves the technical problems of "convenient operation, green environmental protection and safety".

[0107] The twenty-second preferred embodiment: the organic solvent is methanol, ethanol, acetonitrile, or toluene; the mass ratio of Formula 5, water, organic solvent, and benzenesulfonic acid is 30:1-5:100-500:11.4-45; the salt formation reaction time is 1-2 hours, after which the temperature needs to be lowered to 0-5℃, crystallization takes 1-2 hours, followed by filtration and drying. This technical solution, while addressing the technical problem of "improving the yield and purity of milobalin benzenesulfonic acid," further solves the technical problems of "convenient operation, green environmental protection, and safety."

[0108] In this invention, Examples 1 and 2 at least support the protection scope of "the R groups in Formula 2 and Formula 3 are all C1-C4 alkyl groups".

[0109] The phrase "The R groups in Formula 2 and Formula 3 are both C1-C4 alkyl groups" is derived from the foregoing explanation and / or Examples 1 and 2 through the common features "Formula 2 and Formula 3". Therefore, those skilled in the art can reasonably infer that the subordinate concepts of the technical features "The R groups in Formula 2 and Formula 3 are both C1-C4 alkyl groups", the essentially equivalent technical means of "The R groups in Formula 2 and Formula 3 are both C1-C4 alkyl groups", and the technical means that can replace "The R groups in Formula 2 and Formula 3 are both C1-C4 alkyl groups" based on existing technology and conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solutions.

[0110] In this invention, Examples 1 and 2 at least support the protection scope of "in step S1, the esterification reaction process includes: first mixing Formula 1 with an alcohol, and then adding an esterification reagent to carry out the esterification reaction".

[0111] The phrase "the esterification process includes: first mixing Formula 1 with an alcohol, then adding an esterification reagent to carry out the esterification reaction" is summarized from the foregoing explanation and / or Examples 1 and 2 based on the common feature "esterification reaction". Therefore, those skilled in the art can reasonably infer that the technical feature "the esterification process includes: first mixing Formula 1 with an alcohol, then adding an esterification reagent to carry out the esterification reaction" is a subordinate concept; the technical means that are essentially equivalent to "the esterification process includes: first mixing Formula 1 with an alcohol, then adding an esterification reagent to carry out the esterification reaction", and the technical means that can replace "the esterification process includes: first mixing Formula 1 with an alcohol, then adding an esterification reagent to carry out the esterification reaction" based on the existing technical level and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0112] In this invention, Examples 1 and 2 at least support the protection scope of "the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol and isobutanol; the esterification reagent is sulfuric acid or thionyl chloride".

[0113] The phrase "the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol" is derived from the foregoing explanation and / or Examples 1 and 2, summarized by the common feature "methanol and ethanol". Therefore, those skilled in the art can reasonably infer that the technical feature "the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol", the subordinate concept of "the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol", the essentially equivalent technical means of "the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol", and the technical means that can replace "the alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol" based on the existing technical level and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0114] The phrase "the esterification reagent is sulfuric acid or thionyl chloride" is derived from the foregoing explanation and / or Examples 1 and 2, based on the common feature "sulfuric acid". Therefore, those skilled in the art can reasonably presume that the technical feature "the esterification reagent is sulfuric acid or thionyl chloride", the subordinate concepts of "the esterification reagent is sulfuric acid or thionyl chloride", the essentially equivalent technical means of "the esterification reagent is sulfuric acid or thionyl chloride", and the technical means that can replace "the esterification reagent is sulfuric acid or thionyl chloride" based on the existing technical level and within the scope of conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0115] In this invention, Examples 1 and 2 at least support the protection scope of "the mass ratio of alcohol to esterification reagent in Formula 1 is 1:4:0.07-0.09".

[0116] The statement "Formula 1, the mass ratio of alcohol to esterifying reagent is 1:4:0.07-0.09" is derived from the foregoing explanation and / or Examples 1 and 2, based on the common feature "adding 50g of Formula 1 and 200g of methanol to a reaction vessel, heating to 30°C and stirring to dissolve, and slowly adding 4.12g of sulfuric acid after the solution becomes clear." Therefore, those skilled in the art can reasonably presume that the technical feature "Formula 1, the mass ratio of alcohol to esterifying reagent is 1:4:0.07-0.09"; the subordinate concept "Formula 1, the mass ratio of alcohol to esterifying reagent is 1:4:0.07-0.09" is essentially equivalent to the technical means; and any technical means that can replace "Formula 1, the mass ratio of alcohol to esterifying reagent is 1:4:0.07-0.09" based on existing technology and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0117] In this invention, Examples 1 and 2 at least support the protection scope of "the mixing temperature is 25℃-35℃; the esterification reaction temperature is 50℃-70℃; and the esterification reaction time is 10-12h".

[0118] The phrase "mixing temperature is 25℃-35℃" is derived from the foregoing explanation and / or Examples 1 and 2, summarized by the common feature "heating to 30℃ and stirring to dissolve". Therefore, those skilled in the art can reasonably infer that the technical feature "mixing temperature is 25℃-35℃", the subordinate concept of "mixing temperature is 25℃-35℃", the essentially equivalent technical means of "mixing temperature is 25℃-35℃", and the technical means that can replace "mixing temperature is 25℃-35℃" based on the existing technical level and within the scope of conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0119] The statement "The esterification reaction temperature is 50℃-70℃, and the esterification reaction time is 10-12h" is derived from the foregoing explanation and / or Examples 1 and 2, summarizing the common features "after addition, the temperature is raised to 65℃ for reflux reaction, and the reaction is held at that temperature for 10h" and "after addition, the temperature is raised to 50℃ for reaction, and the reaction is held at that temperature for 12h". Therefore, those skilled in the art can reasonably infer that the subordinate concepts of the technical features "the esterification reaction temperature is 50℃-70℃, and the esterification reaction time is 10-12h", the essentially equivalent technical means of "the esterification reaction temperature is 50℃-70℃, and the esterification reaction time is 10-12h", and the technical means that can replace "the esterification reaction temperature is 50℃-70℃, and the esterification reaction time is 10-12h" based on existing technical levels and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0120] In this invention, Examples 1 and 2 at least support the protection range of "after the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH needs to be adjusted to 6-7, the liquid phase needs to be distilled under reduced pressure, toluene needs to be added, the pH needs to be adjusted to 8-9, and the liquid phase needs to be separated and the organic phase concentrated".

[0121] "After the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is adjusted to 6-7, and the mixture is distilled under reduced pressure. Then, toluene is added, the pH is adjusted to 8-9, and the mixture is separated and the organic phase is concentrated." This is summarized from the above explanation and / or Examples 1 and 2, which share the common characteristic of "after the heat preservation is completed, TLC (developing solvent is ethyl acetate: petroleum ether = 1:2, v / v) detects no raw material spot, then the temperature is lowered to 25℃, 10% sodium carbonate aqueous solution is added to adjust the pH to 6-7, and the mixture is distilled under reduced pressure at 50℃ until no methanol distillate is distilled out. 200g of toluene is added to the reaction vessel, solid sodium carbonate is added to adjust the pH to 8.0-9.0, the mixture is stirred evenly, and then the mixture is separated and the organic phase is concentrated." Therefore, based on reasonable presumption, those skilled in the art can determine that the technical feature "after the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is first adjusted to 6-7, vacuum distillation is performed, then toluene is added, the pH is adjusted to 8-9, and the liquid-liquid mixture is separated and the organic phase is concentrated" and the subordinate concept of "after the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is first adjusted to 6-7, vacuum distillation is performed, then toluene is added, the pH is adjusted to 8-9, and the liquid-liquid mixture is separated and the organic phase is concentrated" are essentially equivalent to the technical means of "after the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is first adjusted to 6-7, vacuum distillation is performed, then toluene is added, the pH is adjusted to 8-9, and the liquid-liquid mixture is separated and the organic phase is concentrated". Furthermore, any technical means that can replace "after the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is first adjusted to 6-7, vacuum distillation is performed, then toluene is added, the pH is adjusted to 8-9, and the liquid-liquid mixture is separated and the organic phase is concentrated" based on existing technical capabilities and conventional technical means and common knowledge should all fall within the protection scope of the aforementioned technical solution.

[0122] In this invention, Examples 3 and 4 at least support the protection range of "in step S2, the enzyme concentration of the TL100L lipase is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g".

[0123] "The concentration of the TL100L lipase is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g," which is summarized from the foregoing explanation and / or Examples 3 and 4 based on the common feature "TL100L lipase." Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical features "the enzyme concentration of the TL100L lipase is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g", "the enzyme concentration of the TL100L lipase is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g", the essentially equivalent technical means of "the enzyme concentration of the TL100L lipase is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g", and the technical means that can replace "the enzyme concentration of the TL100L lipase is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g" based on existing technical levels and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0124] In this invention, Examples 3 and 4 at least support the protection scope of "in step S2, the reaction process includes: compound formula 1 is dissolved in buffer and alcohol reagent, and then reacted with TL100 enzyme".

[0125] "In step S2, the reaction process includes: dissolving compound formula 1 in buffer solution and alcohol reagent, and then reacting it with TL100 enzyme," which is summarized from the foregoing explanation and / or Examples 3 and 4 with the common feature "adding 100g of formula 1 and 500g of potassium dihydrogen phosphate buffer (the buffer solution is prepared by dissolving 5g of potassium dihydrogen phosphate in 1000g of water, then adding sodium carbonate to adjust the pH of the system to 7.2-7.5) and 50g of methanol to the reaction vessel, stirring and cooling to 10°C, adding 15g of TL100 enzyme, and incubating the reaction for 24-48h." Therefore, based on reasonable presumption, those skilled in the art can determine that the technical feature “in step S2, the reaction process includes: compound formula 1 is dissolved in buffer solution and alcohol reagent, and then reacted with TL100 enzyme”, the subordinate concept of A, the technical means that are essentially equivalent to “in step S2, the reaction process includes: compound formula 1 is dissolved in buffer solution and alcohol reagent, and then reacted with TL100 enzyme”, and the technical means that can replace “in step S2, the reaction process includes: compound formula 1 is dissolved in buffer solution and alcohol reagent, and then reacted with TL100 enzyme” based on the existing level of technology and conventional technical means and common knowledge, should all fall within the protection scope of the above technical solution.

[0126] In this invention, Examples 3 and 4 at least support the protection scope of "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer or sodium phosphate buffer; the alcohol reagent is methanol or ethanol; the mass ratio of Formula 1, buffer solution, alcohol reagent and TL100 enzyme is 20:100-150:10-20:3-5".

[0127] The phrase "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer" is derived from the foregoing explanation and / or Examples 3 and 4, summarizing the common feature "potassium dihydrogen phosphate buffer." Therefore, those skilled in the art can reasonably infer that the technical feature "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer," the subordinate concepts of "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer," the essentially equivalent technical means of "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer," and the technical means that can replace "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer" based on existing technology and conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0128] The phrase "the alcohol reagent is methanol or ethanol" is derived from the foregoing explanation and / or Examples 3 and 4, summarizing the common feature "methanol or ethanol". Therefore, those skilled in the art can reasonably infer that the technical feature "the alcohol reagent is methanol or ethanol", the subordinate concept of "the alcohol reagent is methanol or ethanol", the essentially equivalent technical means of "the alcohol reagent is methanol or ethanol", and the technical means that can replace "the alcohol reagent is methanol or ethanol" based on the existing technical level and within the scope of conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0129] The mass ratio of Formula 1, buffer solution, alcohol reagent, and TL100 enzyme is 20:100-150:10-20:3-5, which is summarized from the foregoing explanation and / or Examples 3 and 4, based on the common feature of "adding 100g of Formula 1, 500g of potassium dihydrogen phosphate buffer (the buffer solution is prepared by dissolving 5g of potassium dihydrogen phosphate in 1000g of water, then adding sodium carbonate to adjust the pH of the system to 7.2-7.5), and 50g of methanol to the reaction vessel, stirring and cooling to 10°C, and then adding 15g of TL100 enzyme". Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical feature “the mass ratio of Formula 1, buffer solution, alcohol reagent and TL100 enzyme is 20:100-150:10-20:3-5”, the technical means that are essentially equivalent to “the mass ratio of Formula 1, buffer solution, alcohol reagent and TL100 enzyme is 20:100-150:10-20:3-5”, and the technical means that can replace “the mass ratio of Formula 1, buffer solution, alcohol reagent and TL100 enzyme is 20:100-150:10-20:3-5” based on the existing technical level and within the scope of conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0130] In this invention, Examples 3 and 4 at least support the protection range of "in step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60h, and the reaction pH is 7.5-8.0".

[0131] "In step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60h, and the reaction pH is 7.5-8.0," which is summarized from the foregoing explanation and / or Examples 3 and 4, based on the common feature that "100g of Formula 1 and 500g of potassium dihydrogen phosphate buffer (the buffer is prepared by dissolving 5g of potassium dihydrogen phosphate in 1000g of water, then adding sodium carbonate to adjust the pH of the system to 7.2-7.5) and 50g of methanol are added to the reaction vessel, stirred and cooled to 10℃, 15g of TL100 enzyme is added, and the reaction is kept at this temperature for 24-48h. During the reaction, the pH of the system is adjusted to 7.5-8.0 with sodium carbonate to maintain the pH stability of the system." Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical feature "in step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60h, and the reaction pH is 7.5-8.0", the essentially equivalent technical means of "in step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60h, and the reaction pH is 7.5-8.0", and the technical means that can replace "in step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60h, and the reaction pH is 7.5-8.0" based on existing technical levels and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0132] In this invention, Example 5 at least supports the protection range of "in step S2, the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g".

[0133] "The concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g," which is summarized from the foregoing explanation and / or Example 5 using the characteristic "CALB lipase." Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical features "the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g", "the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g", the essentially equivalent technical means of "the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g", and the technical means that can replace "the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g" based on existing technical levels and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0134] In this invention, Example 5 at least supports the protection scope of "in step S2, the hydrolysis process includes: dissolving Formula 2 in buffer solution, and then adding CALB lipase for hydrolysis".

[0135] "In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution, and then adding CALB lipase for hydrolysis," which is summarized from the foregoing explanation and / or Example 5 with the characteristic "adding 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer (the preparation method of the buffer solution is the same as in Example 3) to the reaction vessel, stirring and cooling to 15°C, adding 10g of CALB enzyme, and incubating the reaction for 24-48h. During the incubation period, the pH of the system is adjusted to 7.6-8.2 with sodium carbonate to maintain the pH stability of the system." Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical feature "In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution and then adding CALB lipase for hydrolysis", "In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution and then adding CALB lipase for hydrolysis", the essentially equivalent technical means of "In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution and then adding CALB lipase for hydrolysis", and the technical means that can replace "In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution and then adding CALB lipase for hydrolysis" based on existing technical levels and conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0136] In this invention, Example 5 at least supports the protection range of "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer or sodium phosphate buffer; the mass ratio of Formula 2, the buffer solution and CALB enzyme is 10:20-60:1-3".

[0137] The phrase "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer" is derived from the foregoing explanation and / or Example 5, specifically from the feature "potassium dihydrogen phosphate buffer." Therefore, those skilled in the art can reasonably infer that the subordinate concepts of the technical feature "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer," the essentially equivalent technical means of "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer," and any technical means that can replace "the buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer" based on existing technology and common knowledge should all fall within the protection scope of the aforementioned technical solution.

[0138] The phrase "the mass ratio of Formula 2, buffer, and CALB enzyme is 10:20-60:1-3" is summarized from the foregoing explanation and / or Example 5, specifically the feature "adding 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer to a reaction vessel, stirring and cooling to 15°C, and then adding 10g of CALB enzyme." Therefore, those skilled in the art can reasonably infer that the subordinate concepts of the technical feature "the mass ratio of Formula 2, buffer, and CALB enzyme is 10:20-60:1-3," the essentially equivalent technical means of "the mass ratio of Formula 2, buffer, and CALB enzyme is 10:20-60:1-3," and any technical means that can replace "the mass ratio of Formula 2, buffer, and CALB enzyme is 10:20-60:1-3" based on existing technology and conventional techniques and common knowledge, should all fall within the protection scope of the aforementioned technical solution.

[0139] In this invention, Example 5 at least supports the protection range of "in step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.2".

[0140] "In step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.2," which is summarized from the foregoing explanation and / or Example 5 with the characteristic "adding 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer to the reaction vessel, stirring and cooling to 15℃, adding 10g of CALB enzyme, and incubating the reaction for 24-48h. During the incubation period, the pH of the system is adjusted to 7.6-8.2 with sodium carbonate to maintain the pH stability of the system." Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical feature "in step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.2", the essentially equivalent technical means of "in step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.2", and the technical means that can replace "in step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.2" based on existing technical level and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0141] In this invention, Example 5 at least supports the protection scope of "in step S2, after the reaction and after the hydrolysis are completed, post-processing is performed, the post-processing includes: first adjusting the pH to 1-1.5, raising the temperature to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, filtering; finally separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases and concentrating under reduced pressure".

[0142] "In step S2, post-treatment is performed after the reaction and after the hydrolysis. The post-treatment includes: first adjusting the pH to 1-1.5, heating to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, filtering; finally separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases, and concentrating under reduced pressure." This is summarized from the foregoing explanation and / or Example 5, specifically the characteristic "adding hydrochloric acid to adjust the pH to 1.0-1.5, stirring for 30 min, heating to 30℃, adding 20g of diatomaceous earth and 300g of ethyl acetate, stirring for 1 h, filtering, separating the layers, extracting the aqueous phase with 300g of ethyl acetate, combining the organic phases, and concentrating under reduced pressure at 55℃ until no fraction remains." Therefore, those skilled in the art can reasonably presume that the technical feature “In step S2, after the reaction and after the hydrolysis, post-treatment is performed, the post-treatment includes: first adjusting the pH to 1-1.5, raising the temperature to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, filtering; finally separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases and concentrating under reduced pressure” and “In step S2, after the reaction and after the hydrolysis, post-treatment is performed, the post-treatment includes: first adjusting the pH to 1-1.5, raising the temperature to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, filtering; finally separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases and concentrating under reduced pressure” are subordinate concepts, ...…” are subordinate concepts. The post-treatment performed after both the reaction and the hydrolysis is completed, including: adjusting the pH to 1-1.5, heating to 25℃-35℃; adding diatomaceous earth and ethyl acetate, filtering; and finally separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases, and concentrating under reduced pressure, are all technical means that are essentially equivalent to the above-mentioned technical solution. Any technical means that can replace the above-mentioned technical solution within the scope of protection, based on existing technology and common knowledge, including the following: after the reaction and the hydrolysis are completed, post-treatment is performed, including: adjusting the pH to 1-1.5, heating to 25℃-35℃; adding diatomaceous earth and ethyl acetate, filtering; and finally separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases, and concentrating under reduced pressure, are also considered equivalent to the above-mentioned technical solution.

[0143] In this invention, Example 6 at least supports the protection scope of "In step S3, the catalyst is selected from one or more of calcium chloride, magnesium chloride and copper sulfate; the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate or ammonium chloride; the mass ratio of the catalyst and the ammonia source in Formula 3 is 5:2-5:8-10".

[0144] The phrase "the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate" is derived from the foregoing explanation and / or Example 6 using the feature "calcium chloride". Therefore, those skilled in the art can reasonably presume that the subordinate concepts of the technical feature "the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate", the essentially equivalent technical means of "the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate", and the technical means that can replace "the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate" based on existing technology and conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0145] The statement that "the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride" is derived from the foregoing explanation and / or Example 6, summarized by the feature "methanol ammonia". Therefore, those skilled in the art can reasonably infer that the subordinate concepts of the technical feature "the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride", the essentially equivalent technical means of "the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride", and the technical means that can replace "the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride" based on existing technology and conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0146] The phrase "Formula 3, the mass ratio of catalyst to ammonia source is 5:2-5:8-10" is summarized from the foregoing explanation and / or Example 6, specifically the feature "adding 50g of Formula 3 and 80.8g of a 25% methanol-ammonia solution to a pressure-resistant reaction vessel, then adding 26.4g of calcium chloride, and slowly heating to 70°C and maintaining the temperature and pressure for 6-12 hours." Therefore, those skilled in the art can reasonably infer that the technical feature "Formula 3, the mass ratio of catalyst to ammonia source is 5:2-5:8-10," the subordinate concepts of "Formula 3, the mass ratio of catalyst to ammonia source is 5:2-5:8-10," the essentially equivalent technical means of "Formula 3, the mass ratio of catalyst to ammonia source is 5:2-5:8-10," and the technical means that can replace "Formula 3, the mass ratio of catalyst to ammonia source is 5:2-5:8-10" based on existing technology and conventional technical means and common knowledge, should all fall within the protection scope of the aforementioned technical solution.

[0147] In this invention, Example 6 at least supports the protection range of "in step S3, the temperature of the ammonolysis reaction is 35℃-75℃, the time of the ammonolysis reaction is 6-12h, and the pressure of the ammonolysis reaction is 0.5-10.0MPa; after the ammonolysis reaction is completed, it is necessary to first cool down to 20℃-35℃, concentrate under reduced pressure; then heat up to 35℃-45℃ and add methanol and water to adjust the pH to 1-2; finally cool down to 0℃-5℃, crystallize, filter and dry".

[0148] "In step S3, the temperature of the ammonolysis reaction is 35℃-75℃, the reaction time is 6-12 hours, and the pressure is 0.5-10.0 MPa; after the ammonolysis reaction, the temperature needs to be lowered to 20℃-35℃ for concentration under reduced pressure; then the temperature is raised to 35℃-45℃, methanol and water are added, and the pH is adjusted to 1-2; finally, the temperature is lowered to 0℃-5℃ for crystallization, filtration, and drying," as summarized in the foregoing explanation and / or Example 6. Therefore, those skilled in the art can reasonably infer that the technical feature "In step S3, the temperature of the ammonolysis reaction is 35℃-75℃, the reaction time is 6-12 hours, and the pressure is 0.5-10.0 MPa; after the ammonolysis reaction, the temperature needs to be lowered to 20℃-35℃ for concentration under reduced pressure; then the temperature is raised to 35℃-45℃, methanol and water are added, and the pH is adjusted to 1-2; finally, the temperature is lowered to 0℃-5℃ for crystallization, filtration, and drying" is appropriate. The text describes a process involving ammonolysis, specifically step S3, where the temperature is 35℃-75℃, the reaction time is 6-12 hours, and the pressure is 0.5-10.0 MPa. It further describes the process of cooling the mixture to 20℃-35℃ for concentration under reduced pressure, then heating it to 35℃-45℃ and adding methanol and water to adjust the pH to 1-2. Finally, it describes cooling the mixture to 0℃-5℃ for crystallization, filtration, and drying. The technical means that are basically equivalent to the following, which are based on the existing technical level and can replace the following, within the scope of conventional technical means and common knowledge: "The temperature of the ammonolysis reaction is 35℃-75℃, the reaction time is 6-12h, the pressure is 0.5-10.0MPa; after the ammonolysis reaction is completed, the temperature needs to be lowered to 20℃-35℃ and concentrated under reduced pressure; then the temperature is raised to 35℃-45℃ and methanol and water are added to adjust the pH to 1-2; finally, the temperature is lowered to 0℃-5℃ for crystallization, filtration and drying" in step S3, should all fall within the protection scope of the above technical solution.

[0149] In this invention, Example 7 at least supports the protection scope of "in step S4, the Hoffmann reaction process includes: first mixing the alkali solution and water, then adding Formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining the product".

[0150] "In step S4, the Hoffmann reaction process includes: first mixing the alkali solution and water, then adding Formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining the product," which is summarized from the foregoing explanation and / or Example 7. Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concept of the technical feature "In step S4, the Hoffmann reaction process includes: first mixing the alkali solution and water, then adding formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining" and the technical means that are basically equivalent to "In step S4, the Hoffmann reaction process includes: first mixing the alkali solution and water, then adding formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining" and the technical means that can replace "In step S4, the Hoffmann reaction process includes: first mixing the alkali solution and water, then adding formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining" based on the existing technical level and within conventional technical means and common knowledge, should all fall within the protection scope of the above technical solution.

[0151] In this invention, Example 7 at least supports the protection scope of "the alkaline solution is a sodium hydroxide, potassium hydroxide or lithium hydroxide solution with a mass fraction of 25-35%; the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite and calcium hypobromite; the mass fraction of the degradation reagent is 5-15%; the mass ratio of Formula 4, degradation reagent, alkaline solution and water is 50:150-200:25-30:20-30".

[0152] The phrase "the alkaline solution is a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%" is derived from the foregoing explanation and / or Example 7, summarized by the feature "28.1g of sodium hydroxide solution with a mass fraction of 30%". Therefore, those skilled in the art can reasonably infer that the subordinate concepts of the technical feature "the alkaline solution is a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%", the essentially equivalent technical means of "the alkaline solution is a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%", and the technical means that can replace "the alkaline solution is a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%" based on existing technology and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0153] The phrase "the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite" is summarized by the foregoing explanation and / or Example 7 using the feature "173g of sodium hypochlorite solution with a mass fraction of 10%". Therefore, those skilled in the art can reasonably presume that the technical feature "the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite", the subordinate concept of "the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite", the essentially equivalent technical means of "the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite", and the technical means that can replace "the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite" based on the existing technical level and within the scope of conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0154] The phrase "the mass fraction of the degradation reagent is 5-15%" is derived from the foregoing explanation and / or Example 7, summarized by the feature "173g of sodium hypochlorite solution with a mass fraction of 10%". Therefore, those skilled in the art can reasonably presume that the technical feature "the mass fraction of the degradation reagent is 5-15%", the subordinate concept of "the mass fraction of the degradation reagent is 5-15%", the essentially equivalent technical means of "the mass fraction of the degradation reagent is 5-15%", and the technical means that can replace "the mass fraction of the degradation reagent is 5-15%" based on the existing technical level and within the scope of conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0155] The phrase "Formula 4, the mass ratio of degradation reagent, alkali solution and water is 50:150-200:25-30:20-30" is summarized from the foregoing explanation and / or Example 7, specifically the characteristic "Add 25g of water and 28.1g of 30% sodium hydroxide solution to the reaction vessel, stir and cool to 0°C, slowly add 50g of Formula 4, controlling the temperature <5°C; after the addition is complete, cool to -5°C and stir for 30 minutes, then slowly add 173g of 10% sodium hypochlorite solution, controlling the temperature ≤0°C". Therefore, based on reasonable presumption, those skilled in the art can determine that the technical feature “the mass ratio of the degradation reagent, alkali solution and water in Formula 4 is 50:150-200:25-30:20-30”, the subordinate concept of “the mass ratio of the degradation reagent, alkali solution and water in Formula 4 is 50:150-200:25-30:20-30”, the technical means that are basically equivalent to “the mass ratio of the degradation reagent, alkali solution and water in Formula 4 is 50:150-200:25-30:20-30”, and the technical means that can replace “the mass ratio of the degradation reagent, alkali solution and water in Formula 4 is 50:150-200:25-30:20-30” based on the existing technical level and within the scope of conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0156] In this invention, Example 7 at least supports the following protection range: "The mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20 to 40 minutes; the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1 to 2 hours, then reacting at 30℃ to 40℃ for 3 to 5 hours; after the Hoffmann reaction is completed, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5 to 6.5, crystallization performed, filtered, and dried."

[0157] "The mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min; the reaction conditions for adding the degradation reagent are: first react at -5℃ to 5℃ for 1-2 h, then react at 30℃ to 40℃ for 3-5 h; after the Hoffmann reaction is completed, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5-6.5, crystallized, filtered, and dried," which is summarized from the foregoing explanation and / or Example 7 in this document. Therefore, those skilled in the art can reasonably presume that the technical features "the mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min; the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1-2 h, then reacting at 30℃ to 40℃ for 3-5 h; after the Hoffman reaction, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5-6.5, crystallization, filtration, and drying" and "the mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min; the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1-2 h, then reacting at 30℃ to 40℃ for 3-5 h; after the Hoffman reaction, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5-6.5, crystallization, filtration, and drying" are subordinate concepts, and "the mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min ... the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1-2 h, then reacting at 30℃ to 40℃ for 3-5 h; after the Hoffman reaction, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5-6.5, crystallization, filtration The following technical means are essentially equivalent to the above-mentioned technical solution: "The mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min; the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1-2 h, then reacting at 30℃ to 40℃ for 3-5 h; after the Hoffman reaction, the temperature needs to be lowered to 20℃ to 30℃, the pH is adjusted to 5.5-6.5, crystallization is performed, filtration is carried out, and drying is performed." These technical means, based on existing technology and conventional technical means and common knowledge, can replace the above-mentioned technical solution with the following: "The mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min; the reaction conditions for adding the degradation reagent are: first reacting at -5℃ to 5℃ for 1-2 h, then reacting at 30℃ to 40℃ for 3-5 h; after the Hoffman reaction, the temperature needs to be lowered to 20℃ to 30℃, the pH is adjusted to 5.5-6.5, crystallization is performed, filtration is carried out, and drying is performed."

[0158] In this invention, Examples 8-11 at least support the protection scope of "In step S5, the salt formation reaction process includes: in an organic solvent, first mix Formula 5 with water, cool to 15-25°C, and then carry out a salt formation reaction with benzenesulfonic acid to obtain".

[0159] “In step S5, the salt formation reaction process includes: mixing Formula 5 with water in an organic solvent, cooling to 15-25°C, and then reacting with benzenesulfonic acid to form a salt, thus obtaining the product,” as summarized in the foregoing explanation and / or Examples 8-11. Therefore, based on reasonable presumption, those skilled in the art can determine that the technical feature “In step S5, the salt-forming reaction process includes: in an organic solvent, first mixing formula 5 with water, cooling to 15-25°C, and then reacting with benzenesulfonic acid to form a salt, thus obtaining”, the subordinate concept of “In step S5, the salt-forming reaction process includes: in an organic solvent, first mixing formula 5 with water, cooling to 15-25°C, and then reacting with benzenesulfonic acid to form a salt, thus obtaining”, the technical means that are basically equivalent to “In step S5, the salt-forming reaction process includes: in an organic solvent, first mixing formula 5 with water, cooling to 15-25°C, and then reacting with benzenesulfonic acid to form a salt, thus obtaining”, and the technical means that can replace “In step S5, the salt-forming reaction process includes: in an organic solvent, first mixing formula 5 with water, cooling to 15-25°C, and then reacting with benzenesulfonic acid to form a salt, thus obtaining” based on existing technical level and conventional technical means and common knowledge, should all fall within the protection scope of the above technical solution.

[0160] In this invention, Examples 8-11 at least support the protection scope of "the organic solvent is methanol, ethanol, acetonitrile or toluene; the mass ratio of Formula 5, water, organic solvent and benzenesulfonic acid is 30:1-5:100-500:11.4-45; the salt formation reaction time is 1-2 hours, after the salt formation reaction is completed, it needs to be cooled to 0℃-5℃, crystallization for 1-2 hours, filtration and drying".

[0161] The phrase "the organic solvent is methanol, ethanol, acetonitrile, or toluene" is derived from the foregoing explanation and / or Examples 8-11, summarizing the common feature "methanol, ethanol, acetonitrile, or toluene". Therefore, those skilled in the art can reasonably infer that the technical feature "the organic solvent is methanol, ethanol, acetonitrile, or toluene", the subordinate concepts of "the organic solvent is methanol, ethanol, acetonitrile, or toluene", the essentially equivalent technical means of "the organic solvent is methanol, ethanol, acetonitrile, or toluene", and the technical means that can replace "the organic solvent is methanol, ethanol, acetonitrile, or toluene" based on the existing technical level and within the scope of conventional technical means and common knowledge should all fall within the protection scope of the above-mentioned technical solution.

[0162] "Formula 5, the mass ratio of water, organic solvent and benzenesulfonic acid is 30:1-5:100-500:11.4-45", which is summarized from the foregoing explanation and / or Examples 8-11. Therefore, based on reasonable presumption, those skilled in the art can determine that the subordinate concepts of the technical feature “the mass ratio of Formula 5, water, organic solvent and benzenesulfonic acid is 30:1-5:100-500:11.4-45”, the technical means that are essentially equivalent to “the mass ratio of Formula 5, water, organic solvent and benzenesulfonic acid is 30:1-5:100-500:11.4-45”, and the technical means that can replace “the mass ratio of Formula 5, water, organic solvent and benzenesulfonic acid is 30:1-5:100-500:11.4-45” based on the existing technical level and within the scope of conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0163] The phrase "the salt-forming reaction takes 1-2 hours, and after the salt-forming reaction, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours for crystallization, followed by filtration and drying" is summarized from the foregoing explanation and / or Examples 8-11. Therefore, those skilled in the art can reasonably infer that the technical feature "the salt-forming reaction takes 1-2 hours, and after the salt-forming reaction, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours for crystallization, followed by filtration and drying," the subordinate concept of "the salt-forming reaction takes 1-2 hours, and after the salt-forming reaction, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours for crystallization, followed by filtration and drying," the essentially equivalent technical means of "the salt-forming reaction takes 1-2 hours, and after the salt-forming reaction, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours for crystallization, followed by filtration and drying," and the technical means that can replace "the salt-forming reaction takes 1-2 hours, and after the salt-forming reaction, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours for crystallization, followed by filtration and drying" based on existing technology and conventional technical means and common knowledge, should all fall within the protection scope of the above-mentioned technical solution.

[0164] The beneficial effects of this invention are as follows: (1) Compared with the prior art, the present invention has better technical effects in terms of yield and purity.

[0165] According to experimental tests, the present invention increases the multi-step yield of milobalin benzyl sulfonate from 60% to over 75% in the prior art; and increases the purity from 90% to over 95% in the prior art.

[0166] (2) The enzyme catalysis method used in this invention is simple to operate, has mild reaction conditions, high yield, and good optical purity. Compared with other existing technologies that use metal catalysts, such as titanium tetrachloride, it not only has a cost advantage but also reduces the pollution of heavy metals to the environment.

[0167] Furthermore, based on the present invention: Based on the comparison of Examples 1-11 and Comparative Examples 1-6, the present invention adopts a combination of the following technical means: “A method for preparing milobalin benzylsulfonic acid, comprising the following steps: S1, using Formula 1 as raw material, obtaining Formula 2 through esterification reaction; S2, using Formula 1 as raw material, obtaining Formula 3 through TL100L lipase reaction; or using Formula 2 as raw material, obtaining Formula 3 through CALB lipase hydrolysis; S3, using Formula 3 as raw material, obtaining Formula 4 through ammonolysis reaction under the action of a catalyst; S4, using Formula 4 as raw material, obtaining Formula 5 through Hoffmann reaction; S5, using Formula 5 as raw material, undergoing salt formation reaction with benzylsulfonic acid to obtain…”, achieving new technical effects: improving the yield and purity of milobalin benzylsulfonic acid, and being convenient, green, environmentally friendly, and safe to operate. The combined technical effect is superior to the sum of the effects of each individual technical means. Detailed Implementation

[0168] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following content is merely an exemplary description of the scope of protection claimed by the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, and such changes should also fall within the scope of protection claimed by the present invention.

[0169] The present invention will be further described below by way of specific embodiments. All instruments, devices, equipment, reagents, and products used in the embodiments of the present invention, unless otherwise specified, were obtained through conventional commercial channels. Specifically, TL100 enzyme and CALB enzyme were purchased from Novozymes; the concentrations of methanol and ethanol were both 99.9%; the concentration of sulfuric acid was 98%; and the concentration of hydrochloric acid was 30-36%.

[0170] Example 1: Preparation of Formula 2 (dimethyl ester compound)

[0171] 50g of Formula 1 and 200g of methanol were added to a reaction vessel, and the mixture was heated to 30°C and stirred to dissolve. After the solution became clear, 4.12g of sulfuric acid was slowly added. After the addition was complete, the mixture was heated to 65°C and refluxed for 10 hours. After the reflux was completed, TLC (ethyl acetate:petroleum ether = 1:2, v / v) showed no starting material spot. The mixture was then cooled to 25°C, and a 10% sodium carbonate aqueous solution was added to adjust the pH to 6-7. The mixture was then distilled under reduced pressure at 50°C until no methanol distilled off. 200g of toluene was added to the reaction vessel, and solid sodium carbonate was added to adjust the pH to 8.0-9.0. After stirring evenly, the mixture was separated, and the organic phase was concentrated to obtain 54.8g of dimethyl ester compound Formula 2, with a yield of 98% and a purity of 99.8%.

[0172] Example 2 Preparation of Formula 2 (diethyl ester compound)

[0173] Add 50g of Formula 1 and 200g of ethanol to a reaction vessel, heat to 30℃ and stir to dissolve. After the solution becomes clear, slowly add 4.12g of sulfuric acid. After the addition is complete, heat to 50℃ and maintain the reaction temperature for 12h. After the reaction is complete, TLC (ethanol: petroleum ether = 1:2, v / v) shows no starting material spot and the temperature is lowered to 25℃. Add 10% sodium carbonate aqueous solution to adjust the pH to 6-7. Distill under reduced pressure at 50℃ until no ethanol distills off. Add 200g of toluene to the reaction vessel, add solid sodium carbonate to adjust the pH to 8.0-9.0, stir well, separate the liquids, concentrate the organic phase, and obtain 59.7g of diethyl ester compound Formula 2, yield: 97.5%, purity: 99.7%.

[0174] Example 3 Preparation of Formula 3 (monomethyl ester compound)

[0175] Add 100g of Formula 1 and 500g of potassium dihydrogen phosphate buffer (the buffer is prepared by dissolving 5g of potassium dihydrogen phosphate in 1000g of water, then adding sodium carbonate to adjust the pH of the system to 7.2-7.5) and 50g of methanol to the reaction vessel, stir and cool to 10℃, add 15g of TL100 enzyme (enzyme concentration of 15-100g / L, enzyme activity of 30000U / g), and incubate the reaction for 24-48h. During the incubation period, adjust the pH of the system to 7.5-8.0 with sodium carbonate to maintain the pH stability of the system. After the reaction of Formula 1 was completed by TLC (ethyl acetate:petroleum ether = 1:2, v / v), hydrochloric acid was added dropwise to adjust the pH to 1.0-1.5. After stirring for 30 min, the temperature was raised to 30 °C, 30 g of diatomaceous earth and 300 g of ethyl acetate were added, and the mixture was stirred for 1 h. After filtration and separation, the aqueous phase was extracted with 300 g of ethyl acetate. The organic phases were combined and concentrated under reduced pressure at 55 °C until no fraction was obtained, yielding 99.5 g of monomethyl ester compound Formula 3, with a yield of 94.1% and a purity of 99.4%.

[0176] Example 4 Preparation of Formula 3 (monoethyl ester compound)

[0177] Add 100g of Formula 1, 500g of potassium dihydrogen phosphate buffer (prepared as in Example 3), and 50g of ethanol to a reaction vessel. Stir and cool to 0°C. Add 15g of TL100L enzyme (enzyme concentration 15-100g / L, enzyme activity 30000U / g). Incubate for 24-50h. During the incubation, adjust the pH of the system to 7.5-8.0 with sodium carbonate to maintain pH stability. Detect the reaction of Formula 1 by TLC (ethyl acetate:petroleum ether = 1:2, v / v). After the reaction is complete, add hydrochloric acid to adjust the pH to 1.0-1.5. Stir for 30min, then heat to 30°C. Add 30g of diatomaceous earth and 300g of ethyl acetate. Stir for 1h, filter, separate into layers, extract the aqueous phase with 300g of ethyl acetate, combine the organic phases, and concentrate under reduced pressure at 55°C until no fraction remains, yielding 104.8g of monoethyl ester compound Formula 3, yield 93.8%, purity 99.6%.

[0178] Example 5 Preparation of Formula 3 (monomethyl ester compound)

[0179] Add 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer (prepared as in Example 3) to a reaction vessel, stir and cool to 15°C, add 10g of CALB enzyme (enzyme concentration 15-100g / L, enzyme activity 30000U / g), and incubate for 24-48h. During the incubation period, adjust the pH of the system to 7.6-8.2 with sodium carbonate to maintain pH stability. After the reaction of Formula 2 is complete, detect it by TLC (ethyl acetate:petroleum ether = 1:2, v / v). Adjust the pH to 1.0-1.5 by adding hydrochloric acid dropwise, stir for 30min, and then heat to 30°C. Add 20g of diatomaceous earth and 300g of ethyl acetate, stir for 1h, filter, separate the layers, extract the aqueous phase with 300g of ethyl acetate, combine the organic phases, and concentrate under reduced pressure at 55°C until no fraction remains, to obtain 85.3g of monomethyl ester compound Formula 3, yield 90.03%, purity: 99.5%.

[0180] Example 6 Preparation of Formula 4

[0181] Add 50g of Formula 3 and 80.8g of a 25% methanol-ammonia solution to a pressure-resistant reaction vessel (0.5-10.0MPa), then add 26.4g of calcium chloride. Slowly raise the temperature to 70℃ and maintain the pressure (0.5-10.0MPa) for 6-12 hours. After the reaction is complete, detect the reaction by TLC (ethanol: petroleum ether = 1:2, v / v). Slowly lower the temperature to 25℃ and transfer the reaction solution in the reaction vessel to another bottle. Concentrate under reduced pressure until no fraction remains. Raise the temperature to 40℃ and add 100g of methanol and 100g of water. Stir well and add hydrochloric acid dropwise to adjust the pH of the system to 1.0-2.0. At this point, solid precipitates. Slowly lower the temperature to 0-5℃ and maintain the temperature for 1 hour to allow crystallization. Filter and dry to obtain 43.9g of Formula 4, with a yield of 93.3% and a purity of 98.9%.

[0182] Example 7 Preparation of Formula 5

[0183] Add 25g of water and 28.1g of 30% sodium hydroxide solution to a reaction vessel, stir and cool to 0℃, then slowly add 50g of Formula 4, keeping the temperature <5℃; after the addition is complete, cool to -5℃ and stir for 30min, then slowly add 173g of 10% sodium hypochlorite solution, keeping the temperature ≤0℃; after the addition is complete, keep the reaction at this temperature for 1-2h, then slowly raise the temperature to 40℃ and keep the reaction at this temperature for 4h; after the reaction is complete, slowly lower the temperature to 25℃, add hydrochloric acid to adjust the pH to 5.5-6.5, stir until a white solid precipitates, keep the temperature at this temperature for 1h to allow crystallization, then slowly cool to 0-5℃, keep the temperature at this temperature for 1h to allow crystallization, filter, dry the wet product, and obtain 40.8g of solid compound Formula 5, yield 92.4%, purity: 99.8%.

[0184] Example 8 Preparation of Formula 6 (Milobalin benzylsulfonate)

[0185] Add 30g of formula 5, 240g of ethanol and 3g of water to the reaction vessel, stir well and then cool to 15-25℃. Slowly add a mixed solution of 22.7g of benzenesulfonic acid and 60g of ethanol. After the addition is complete, keep the mixture warm and stir for 1-2 hours. After the warming is complete, slowly cool to 0℃-5℃ and stir to precipitate crystals for 2 hours. Filter, wash with ice-cold ethanol, and dry the wet product to obtain 50.8g of milobalin benzenesulfonic acid, with a yield of 96.4% and a purity of 99.9%.

[0186] Example 9 Preparation of Formula 6 (Milobalin benzylsulfonate) Add 30g of Formula 5, 240g of methanol and 3g of water to a reaction vessel, stir well and then cool to 15-25℃. Slowly add a mixed solution of 22.7g of benzenesulfonic acid and 60g of methanol. After the addition is complete, keep the mixture warm and stir for 1-2 hours. After the warming is complete, slowly cool to 0℃-5℃ and stir to induce crystallization for 2 hours. Filter, wash with ice-cold ethanol, and dry the wet product to obtain 51.2g of milobalin benzenesulfonic acid, with a yield of 97.2% and a purity of 99.9%.

[0187] Example 10 Preparation of Formula 6 (Milobalin benzylsulfonate) Add 30g of formula 5, 240g of acetonitrile and 3g of water to the reaction vessel, stir well and then cool to 15-25℃. Slowly add a mixed solution of 22.7g of benzenesulfonic acid and 60g of acetonitrile. After the addition is complete, keep the mixture warm and stir for 1-2 hours. After the warming is complete, slowly cool to 0℃-5℃ and stir to precipitate crystals for 2 hours. Filter, wash with ice-cold acetonitrile, and dry the wet product to obtain 49.7g of milobalin benzenesulfonic acid, with a yield of 94.3% and a purity of 99.9%.

[0188] Example 11 Preparation of Formula 6 (Milobalin benzylsulfonate) Add 30g of formula 5, 240g of toluene and 3g of water to a reaction vessel, stir until homogeneous, and then cool to 15-25℃. Slowly add a mixed solution of 22.7g of benzenesulfonic acid and 60g of toluene dropwise. After the addition is complete, keep the mixture warm and stir for 1-2 hours. After the warming is complete, slowly cool the mixture to 0℃-5℃ and stir to induce crystallization for 2 hours. Filter the solution, wash with icy toluene, and dry the wet product to obtain 47.5g of milobalin benzenesulfonic acid, with a yield of 90.1% and a purity of 99.9%.

[0189] Comparative Example 1 Compared with Example 1, the only difference is the reaction temperature and time.

[0190] Add 50g of Formula 1 and 200g of methanol to a reaction vessel, heat to 30℃ and stir to dissolve; after the solution becomes clear, slowly add 4.12g of sulfuric acid, then heat to 40℃ and maintain the temperature for 20-30h; after the temperature maintenance, cool to 25℃, add 10% sodium carbonate aqueous solution to adjust the pH to 6-7, distill under reduced pressure at 50℃ until no methanol distillate, add 200g of toluene to the reaction vessel, add sodium carbonate to adjust the pH to 8.0-9.0, stir evenly, separate the liquids, concentrate the organic phase to obtain 41.4g of dimethyl ester compound Formula 2, yield: 84.1%, purity: 90.4%.

[0191] It can be seen that reducing the reaction temperature to 40℃ significantly increases the reaction time, and the esterification effect is poor, with both purity and yield decreasing.

[0192] Comparative Example 2 Compared with Example 3, the only difference is the amount of TL100 enzyme added and the reaction time.

[0193] Add 100g of Formula 1 and 500g of potassium dihydrogen phosphate buffer (the buffer is prepared by dissolving 5g of potassium dihydrogen phosphate in 1000g of water, then adding sodium carbonate to adjust the pH of the system to 7.2-7.5) and 50g of methanol to the reaction vessel, stir and cool to 10℃, add 5g of TL100 enzyme (enzyme concentration of 15-100g / L, enzyme activity of 30000U / g), and incubate the reaction for 60-72h. During the incubation period, adjust the pH of the system to 7.5-8.0 with sodium carbonate to maintain the pH stability of the system. After the reaction of Formula 1 was completed by TLC (ethyl acetate:petroleum ether = 1:2, v / v), hydrochloric acid was added dropwise to adjust the pH to 1.0-1.5. After stirring for 30 min, the temperature was raised to 30 °C, 30 g of diatomaceous earth and 300 g of ethyl acetate were added, and the mixture was stirred for 1 h. After filtration and separation, the aqueous phase was extracted with 300 g of ethyl acetate. The organic phases were combined and concentrated under reduced pressure at 55 °C until no fraction was obtained, yielding 89.1 g of monomethyl ester compound Formula 3, with a yield of 84.2% and a purity of 98.4%.

[0194] It can be seen that reducing the amount of enzyme added significantly increases the reaction time, while reducing both purity and yield.

[0195] Comparative Example 3 Compared with Example 4, the only difference is that the type of enzyme and the reaction time are changed.

[0196] 100g of Formula 1, 500g of potassium dihydrogen phosphate buffer (prepared as in Example 3), and 50g of ethanol were added to a reaction vessel. The mixture was stirred and cooled to 0°C. 15g of Novozymes RM IM enzyme (enzyme concentration 15-100g / L, enzyme activity 30000U / g) was added, and the reaction was incubated. During the incubation period, the pH of the system was adjusted to 7.5-8.0 with sodium carbonate to maintain pH stability. After the reaction of Formula 1 was complete (90h total reaction time) by TLC (ethyl acetate:petroleum ether = 1:2, v / v), hydrochloric acid was added dropwise to adjust the pH to 1.0-1.5. After stirring for 30min, the temperature was raised to 30°C, 30g of diatomaceous earth and 300g of ethyl acetate were added, and the mixture was stirred for 1h. After filtration and separation, the aqueous phase was extracted with 300g of ethyl acetate. The organic phases were combined and concentrated under reduced pressure at 55°C until no fraction was obtained, yielding 69.5g of monoethyl ester compound Formula 3, with a yield of 62.2% and a purity of 91.2%.

[0197] It can be seen that changing the type of enzyme significantly increases the reaction time, while reducing both purity and yield.

[0198] Comparative Example 4 Compared with Example 5, the only difference is the amount of CALB enzyme added and the reaction time.

[0199] Add 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer (prepared as in Example 3) to a reaction vessel, stir and cool to 15°C, add 3g of CALB enzyme (enzyme concentration 15-100g / L, enzyme activity 30000U / g), and incubate for 60-72h. During the incubation period, adjust the pH of the system to 7.6-8.2 with sodium carbonate to maintain pH stability. After the reaction of Formula 2 is complete, detect it by TLC (ethyl acetate:petroleum ether = 1:2, v / v). Adjust the pH to 1.0-1.5 by adding hydrochloric acid dropwise, stir for 30min, raise the temperature to 30°C, add 20g of diatomaceous earth and 300g of ethyl acetate, stir for 1h, filter, separate the layers, extract the aqueous phase with 300g of ethyl acetate, combine the organic phases, and concentrate under reduced pressure at 55°C until no fraction remains, to obtain 81.7g of monomethyl ester compound Formula 3, yield 86.3%, purity: 98.1%.

[0200] It can be seen that reducing the amount of enzyme added significantly increases the reaction time, while reducing both purity and yield.

[0201] Comparative Example 5 Compared with Example 5, the only difference is that the type of enzyme and the reaction time are changed.

[0202] 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer (prepared as in Example 3) were added to a reaction vessel. The mixture was stirred and cooled to 15°C. 10g of Novozymes TL-IM lipase (enzyme concentration 15-100g / L, enzyme activity 30000U / g) was added, and the reaction was incubated. During the incubation period, the pH of the system was adjusted to 7.6-8.2 with sodium carbonate to maintain pH stability. After the reaction of Formula 2 was complete (64h total reaction time) by TLC (ethyl acetate:petroleum ether = 1:2, v / v), hydrochloric acid was added dropwise to adjust the pH to 1.0-1.5. After stirring for 30min, the temperature was raised to 30°C, 20g of diatomaceous earth and 300g of ethyl acetate were added, and the mixture was stirred for 1h. After filtration and separation, the aqueous phase was extracted with 300g of ethyl acetate. The organic phases were combined and concentrated under reduced pressure at 55°C until no fraction was obtained, yielding 51.3g of monomethyl ester compound Formula 3, with a yield of 54.2% and a purity of 92.4%.

[0203] It can be seen that changing the type of enzyme significantly increases the reaction time, while reducing both purity and yield.

[0204] Comparative Example 6 Compared with Example 5, the only difference is that the type of enzyme and the reaction time are changed.

[0205] 100g of Formula 2 and 500g of potassium dihydrogen phosphate buffer (prepared as in Example 3) were added to a reaction vessel. The mixture was stirred and cooled to 15°C. 10g of immobilized NS 88011 lipase (enzyme concentration 15-100g / L, enzyme activity 30000U / g) was added, and the reaction was incubated. During the incubation period, the pH of the system was adjusted to 7.6-8.2 with sodium carbonate to maintain pH stability. After the reaction of Formula 2 was complete (total reaction time 80h) by TLC (ethyl acetate:petroleum ether = 1:2, v / v), hydrochloric acid was added dropwise to adjust the pH to 1.0-1.5. After stirring for 30min, the temperature was raised to 30°C, 20g of diatomaceous earth and 300g of ethyl acetate were added, and the mixture was stirred for 1h. After filtration and separation, the aqueous phase was extracted with 300g of ethyl acetate. The organic phases were combined and concentrated under reduced pressure at 55°C until no fraction was obtained, yielding 77.8g of monomethyl ester compound Formula 3, with a yield of 82.1% and a purity of 99.5%.

[0206] It can be seen that changing the type of enzyme significantly increases the reaction time, while reducing both purity and yield.

[0207] 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 preparing milobalin benzylsulfonic acid, characterized in that, Includes the following steps: S1. Using Formula 1 as raw material, Formula 2 is obtained through esterification reaction; S2. Using Formula 1 as raw material, Formula 3 is obtained by reaction with TL100L lipase; or using Formula 2 as raw material, Formula 3 is obtained by hydrolysis with CALB lipase. S3. Using Formula 3 as raw material, Formula 4 is obtained through ammonolysis under the action of a catalyst; S4. Using Formula 4 as raw material, Formula 5 is obtained through the Hoffmann reaction; S5. Using Formula 5 as a raw material, react with benzenesulfonic acid to form a salt, and the product is obtained. The synthesis route is as follows: 。 2. The preparation method according to claim 1, characterized in that, The R groups in both Formula 2 and Formula 3 are C1-C4 alkyl groups.

3. The preparation method according to claim 1, characterized in that, In step S1, the esterification reaction process includes: first mixing Formula 1 with an alcohol, and then adding an esterification reagent to carry out the esterification reaction.

4. The preparation method according to claim 3, characterized in that, The alcohol is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, and isobutanol; the esterification reagent is sulfuric acid or thionyl chloride.

5. The preparation method according to claim 3, characterized in that, The mass ratio of the alcohol to the esterification reagent in Formula 1 is 1:4:0.07-0.

09.

6. The preparation method according to claim 3, characterized in that, The mixing temperature is 25℃-35℃; the esterification reaction temperature is 50℃-70℃, and the esterification reaction time is 10-12h.

7. The preparation method according to claim 3, characterized in that, After the esterification reaction is completed, the temperature needs to be lowered to 20℃-35℃, the pH is adjusted to 6-7, the mixture is distilled under reduced pressure, toluene is added, the pH is adjusted to 8-9, and the liquid-liquid phase and organic phase are separated and concentrated.

8. The preparation method according to claim 1, characterized in that, In step S2, the concentration of the TL100L lipase solution is 15-100g / L, and the enzyme activity of the TL100L lipase is not less than 5000U / g.

9. The preparation method according to claim 1, characterized in that, In step S2, the reaction process includes: dissolving compound formula 1 in buffer solution and alcohol reagent, and then reacting it with TL100 enzyme.

10. The preparation method according to claim 9, characterized in that, The buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer; the alcohol reagent is methanol or ethanol; the mass ratio of Formula 1, buffer solution, alcohol reagent, and TL100 enzyme is 20:100-150:10-20:3-5.

11. The preparation method according to claim 9, characterized in that, In step S2, the reaction temperature is 0℃-30℃, the reaction time is 24-60h, and the reaction pH is 7.5-8.

0.

12. The preparation method according to claim 1, characterized in that, In step S2, the concentration of the CALB lipase solution is 15-100 g / L, and the enzyme activity of the CALB lipase is not less than 5000 U / g.

13. The preparation method according to claim 1, characterized in that, In step S2, the hydrolysis process includes: dissolving Formula 2 in a buffer solution and then adding CALB lipase for hydrolysis.

14. The preparation method according to claim 13, characterized in that, The buffer solution is potassium phosphate buffer, potassium dihydrogen phosphate buffer, or sodium phosphate buffer; the mass ratio of the buffer solution and CALB enzyme in Formula 2 is 10:20-60:1-3.

15. The preparation method according to claim 13, characterized in that, In step S2, the hydrolysis temperature is 0℃-30℃, the hydrolysis time is 24-60h, and the hydrolysis pH is 7.6-8.

2.

16. The preparation method according to claim 1, characterized in that, In step S2, post-treatment is performed after the reaction and after the hydrolysis. The post-treatment includes: first adjusting the pH to 1-1.5, then heating to 25℃-35℃; then adding diatomaceous earth and ethyl acetate, and filtering; finally separating the phases, extracting the aqueous phase with ethyl acetate, combining the organic phases and concentrating under reduced pressure.

17. The preparation method according to claim 1, characterized in that, In step S3, the catalyst is selected from one or more of calcium chloride, magnesium chloride, and copper sulfate; the ammonia source for the ammonolysis reaction is ammonia gas, liquid ammonia, ammonia water, methanol ammonia, ammonium carbonate, ammonium acetate, or ammonium chloride; the mass ratio of the catalyst and the ammonia source in Formula 3 is 5:2-5:8-10.

18. The preparation method according to claim 1, characterized in that, In step S3, the temperature of the ammonolysis reaction is 35℃-75℃, the reaction time is 6-12h, and the pressure is 0.5-10.0MPa. After the ammonolysis reaction is completed, the temperature needs to be lowered to 20℃-35℃ and concentrated under reduced pressure. Then, the temperature is raised to 35℃-45℃ and methanol and water are added to adjust the pH to 1-2. Finally, the temperature is lowered to 0℃-5℃ to crystallize, filter, and dry.

19. The preparation method according to claim 1, characterized in that, In step S4, the Hoffmann reaction process includes: first mixing the alkaline solution and water, then adding Formula 4, stirring, and finally adding the degradation reagent to react, thus obtaining the product.

20. The preparation method according to claim 19, characterized in that, The alkaline solution is a sodium hydroxide, potassium hydroxide, or lithium hydroxide solution with a mass fraction of 25-35%; the degradation reagent is selected from one or more of sodium hypochlorite, sodium hypobromite, calcium hypochlorite, and calcium hypobromite; the mass fraction of the degradation reagent is 5-15%; the mass ratio of Formula 4, degradation reagent, alkaline solution, and water is 50:150-200:25-30:20-30.

21. The preparation method according to claim 19, characterized in that, The mixing temperature is -1℃ to 1℃; the stirring temperature is -5℃ to 5℃, and the stirring time is 20-40 min; the reaction conditions for adding the degradation reagent are: first react at -5℃ to 5℃ for 1-2 h, then react at 30℃ to 40℃ for 3-5 h; after the Hoffmann reaction is completed, the temperature needs to be lowered to 20℃ to 30℃, the pH adjusted to 5.5-6.5, crystallized, filtered, and dried.

22. The preparation method according to claim 1, characterized in that, In step S5, the salt formation reaction process includes: mixing Formula 5 with water in an organic solvent, cooling the temperature to 15-25°C, and then reacting it with benzenesulfonic acid to form a salt, thus obtaining the product.

23. The preparation method according to claim 22, characterized in that, The organic solvent is methanol, ethanol, acetonitrile, or toluene; the mass ratio of Formula 5, water, organic solvent, and benzenesulfonic acid is 30:1-5:100-500:11.4-45; the salt formation reaction takes 1-2 hours, and after the salt formation reaction is completed, the temperature needs to be lowered to 0℃-5℃ for 1-2 hours to allow crystallization, followed by filtration and drying.

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