72 results about "Salt formation" patented technology

The invention discloses a preparation method of 3-quinuclidinone hydrochloride, which comprises the following steps: carrying out temperature control reaction on 4-picolinic acid and chloroacetic acid under alkaline water conditions to obtain an aqueous solution of a compound a, and directly entering the next reaction without post-treatment after the reaction is finished; adding a reducing agent alkaline water system into the aqueous solution of the compound a, controlling the temperature to react, controlling the temperature to adjust the pH value to 5-5.5 after the reaction is finished, extracting with n-butyl alcohol, and drying to obtain an n-butyl alcohol solution of a compound b, and directly entering the next reaction step; wherein the reducing agent is one of sodium borohydride and potassium borohydride; dropwise adding thionyl chloride into an n-butyl alcohol solution of the compound b, controlling the temperature to react after dropwise adding is ended, and concentrating to remove the solvent and unreacted thionyl chloride after the reaction is ended, so as to obtain a compound c; carrying out Dieckmann condensation reaction on the compound c at controlled temperature under the condition of organic alkali by using toluene as a solvent, carrying out hydrochloric acid quenching reaction after the reaction is finished, and directly carrying out next-step reaction after extracting and removing impurities from a water phase containing a hydrochloride solution of a compound d by using toluene; and carrying out a decarboxylation reaction on the compound d in a hydrochloric acid aqueous solution at controlled temperature, after the reaction is finished, adjusting the pH value to 10-13, extracting, and salifying to obtain a target compound TM, namely 3-quinuclidinone hydrochloride. The preparation method of 3-quinuclidinone hydrochloride provided by the invention has the advantages of economical and easily available raw materials, mild reaction conditions, efficient reaction, simple operation and low cost, and is suitable for industrial application.

The application belongs to the technical field of pharmaceutical chemistry synthesis, and specifically discloses a preparation method of oseltamivir and a phosphate thereof and an intermediate thereof, which comprises the following steps: (1) a compound of formula VII is reacted with VIII under the action of a base in a solvent to obtain an intermediate of formula VI, and then the intermediate of formula VI is reacted under the action of a strong base at high temperature to obtain formula V; (2) formula V is subjected to ring-opening reaction with tert-butylamine in a solvent under the catalysis of a Lewis acid to obtain formula IV; (3) formula IV is reacted with an acetylating agent in a solvent under the action of a base to obtain formula III; (4) formula III is reacted under the action of an acid at a certain temperature to obtain formula II; and (5) formula II is subjected to salt formation with phosphoric acid in a solvent to obtain oseltamivir. The preparation method has the characteristics of simple operation, low cost, high yield, high optical purity of the product, stable process and the like, and is suitable for industrial production.

This invention relates to the field of pharmaceutical technology and discloses a method for improving the clarity and color of oxybuprocaine hydrochloride solution, comprising the following steps: S110: Oxoplasmin is added to a reactor, and an organic solvent is added while stirring to control the reaction system at 0-10°C; an antioxidant is added. S120: Hydrochloric acid is slowly added in batches to the temperature-controlled reaction system. After the addition is complete, the temperature is controlled at 0-10°C for 2-4 hours, then the temperature is raised to 40-50°C for 2-4 hours, and activated carbon is added. S130: The mixture is filtered while hot, and solvent is slowly added dropwise to the filtrate until the product precipitates. After slurrying at 25-35°C for 2 hours, the mixture is filtered, and the filter cake is vacuum dried in a vacuum drying oven at 40-50°C for 12-16 hours to obtain oxybuprocaine hydrochloride. This invention provides a novel method for obtaining oxybuprocaine hydrochloride by adding antioxidants and activated carbon in the salt formation step. The clarity and color of the resulting product solution meet pharmacopoeia requirements.

The application discloses a synthesis method of 3,3-difluorocyclopentylamine hydrochloride, and particularly relates to the technical field of chemical synthesis. The synthesis method comprises the following steps: taking 2-cyclopentenone and phthalimide as raw materials, and sequentially performing a Michael addition reaction, deoxygenation fluorination, removal of a phthaloyl protecting group, Boc protection and deprotection and salt formation reaction to obtain 3,3-difluorocyclopentylamine hydrochloride. The synthesis route and process design of the application are reasonable, the starting raw material is 2-cyclopentenone, the required reaction condition is mild, the post-treatment method is simple, the operability is strong, the raw material and reagent are cheap and easy to obtain, and the total yield can reach 43.6%, so the synthesis method has large-scale preparation value.

The invention relates to the technical field of organic synthesis, in particular to a refining method of a crude product of dextroborneol, which comprises the following steps: sequentially carrying out a rearrangement reaction, an esterification reaction, a salt forming reaction, an alkaline hydrolysis reaction and post-treatment refining on the crude product of dextroborneol in the presence of a solvent and a catalyst on the basis of a reaction product to obtain a refined product of dextroborneol, in the refined dextroborneol product, the content of dextroborneol is greater than or equal to 98.0%, the content of L-borneol is less than or equal to 1.0%, the content of isoborneol is less than or equal to 0.15%, the content of natural camphor is less than or equal to 0.15%, and the content of other impurities is less than or equal to 0.10%. The method has the advantages that the isoborneol structure can be selectively destroyed under mild conditions, impurities are effectively removed through the esterification-salification-alkaline hydrolysis three-step reaction, and the purity and yield of dextroborneol are remarkably improved.

The invention belongs to the field of medicinal chemistry, and particularly relates to a preparation method of a lutrombopag intermediate, which comprises the step of preparing an intermediate I p-toluenesulfonate by using a new salifying system.

The application discloses a preparation method of a trans-7H-pyrrolo[2,3-d]pyrimidine compound, and the full name of the trans-7H-pyrrolo[2,3-d]pyrimidine compound is trans-N-methyl-4-(methyl-7H-pyrrolo[2,3-d]pyrimidin-4-ylamino)cyclohexylmethanesulfonamide maleate, which is prepared from trans-4-[(tert-butoxycarbonyl)amino]cyclohexane carboxylic acid and 4-chloro-7H-pyrrolo[2,3-d]pyrimidine as starting materials through reduction, chlorination, substitution, oxidation, methylation, condensation and salt formation reactions. The preparation method has the advantages of few reaction steps, simple operation, low production cost, high production efficiency, high yield, high product purity and suitability for scale-up production.

A method for resolving a phenylalanine derivative of formula (I), and an intermediate. The method comprises: a resolving step comprising using a resolving reagent to react with the phenylalanine derivative represented by formula (I) in a reaction solvent to obtain a resolved intermediate, wherein the resolving reagent is selected from N-acetyl-D-phenylalanine and / or (2R,3R)-(−)-dibenzoyl-L-tartaric acid, and the reaction solvent is selected from 90-99% aqueous ethanol, absolute ethyl alcohol, or acetone. The method uses a chiral reagent to perform salt formation and racemate resolution, and has the advantages of being easy to operate, requiring no special production devices, and being easy to scale up production.

The application provides a kind of solvent-free salt formation reaction equipment and process, shell is provided with feed inlet, feed inlet is connected with the grinding chamber in the shell feed, temperature control sleeve is arranged outside the grinding chamber, and the reaction cabin capable of overturning is arranged in the grinding chamber;Ultrasonic tool head is arranged on the grinding chamber above the reaction cabin, the top cover of the reaction cabin can be opened and closed, and the bottom cover of the reaction cabin is hollow fiber reverse osmosis membrane.The process of the application is simple, the combination device can effectively eliminate the influence of raw material residues, the water is removed quickly and completely, the reaction time is short, the energy consumption is low, the content of the obtained product is high, the impurities are few, and a new idea is provided for the synthesis of related products of such raw materials.

The invention provides a preparation method and application of a ziprasidone related substance B, and belongs to the technical field of heterocyclic compound synthesis. Ziprasidone is taken as an object, ziprasidone is salified to synthesize ziprasidone mesylate, ziprasidone mesylate is dissolved and dispersed in a solvent containing activated carbon, after 5-7 days of standing, the solvent is filtered and concentrated, and a related substance B is obtained through crystallization. When the scheme is applied to crystallization of ziprasidone salt, generation of a related substance B can be effectively inhibited, and the product quality is improved.

This invention discloses a method for synthesizing an intermediate of retinoic acid, relating to the field of pharmaceutical organic synthesis technology, comprising the following steps: S1, in the presence of a base, 2-amino-3-chloropyridine and 4-bromopiperidine undergo a nucleophilic substitution reaction in solvent A to prepare compound III; S2, in the presence of a catalyst and ammonia solution, compound III undergoes an amination reaction in solvent B to prepare compound II; S3, compound II is dissolved in solvent C, and sequentially undergoes CDI cyclization and hydrogen chloride solution salt formation to prepare compound I, namely 1-(piperidin-4-yl)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one. This invention is low-cost, uses mild reaction conditions, has a simple synthesis process, high yield, and eliminates the need for expensive and potentially unsafe excipients, effectively improving reaction safety, being environmentally friendly, and suitable for industrial production.

The invention discloses a synthesis method of an FLT3 inhibitor of quinatinib dihydrochloride. According to the method disclosed by the invention, the raw material drug of the quinatinib dihydrochloride is synthesized and prepared through seven chemical reactions including Boc protecting group feeding, bromination reaction, condensation ring closing reaction, Boc protecting group removal, phosgene condensation reaction, final etherification reaction to obtain the quinatinib, and final salification. The method has the advantages of wide raw material source, low cost, simplicity in operation, high product recovery rate, easiness in industrial industrialization and the like.

The present invention relates to the field of medical intermediates, and provides a preparation method for a key intermediate tert-butyl (3aR,5S,6aS)-5-(methylamino)hexahydrocyclopenta[c]pyrrole-2(1H)-carboxylate mesylate of a JAK kinase inhibitor. The method comprises: reacting tert-butyl cis-5-oxohexahydrocyclopenta[C]pyrrole-2(1H)-carboxylate as a raw material with a methylamine equivalent to obtain intermediate A; and then carrying out a reduction reaction in metallic sodium and isopropanol to obtain a crude product, adding L-DBTA to form a salt, removing isomers, and then carrying out re-liberation and salt formation with methanesulfonic acid to obtain a purified product. The method significantly reduces reaction steps, reduces raw material costs, has a simple and reliable process, and is easy for industrial production.

The application relates to the technical field of permanent ferrite preparation, in particular to a method for preparing strontium ferrite by a multi-field coupling auxiliary molten salt method. First, a chemical coprecipitation method is improved to obtain a mixture containing an excess precipitant, inorganic salt and strontium ferrite precursor; then the mixture is subjected to heat treatment under multi-field coupling; finally, strontium ferrite powder is obtained after washing and drying. The application simplifies the chemical coprecipitation process, avoids Sr loss and realizes in-situ salt formation; a multi-element molten salt system is constructed during heat treatment, and an alkali-containing molten salt system with activation is proposed; in the molten salt liquid phase environment, multi-physical fields such as magnetic fields and ultrasonic vibration force fields are cooperated to control the orientation and growth of grains, new driving force and fast channels are provided for ion diffusion, and the rapid synthesis of strontium ferrite and the control of microstructure and size are realized in a low temperature and short time.

This invention relates to the field of materials technology, and more particularly to a 3D-printed, internally hollowed-cone solar interface evaporator with directional salt deposition function, its preparation method, and its application. The invention includes step 1: three-dimensional model construction; step 2: substrate surface pretreatment and chemical activation; and step 3: hydrothermal preparation of a Co-Bi-S coating. This invention uses a 3D-printed porous, internally hollowed-cone resin device as a substrate, and grows a Co-Bi-S coating in situ on its surface using a hydrothermal method. This coating exhibits both excellent photothermal conversion performance and corrosion resistance. The evaporator structure is designed as a porous, internally hollowed-cone shape, which provides a larger evaporation area, stronger light capture and focusing capabilities, and can achieve higher evaporation temperatures and directional salt deposition effects. The prepared solar interface evaporator exhibits excellent photothermal conversion performance and water evaporation efficiency, and also demonstrates good structural stability and corrosion resistance. This solves the technical problems of low photothermal conversion efficiency and poor stability in high-salt environments inherent in traditional solar evaporators, making it suitable for applications such as seawater desalination.

This invention provides a method for preparing labetalol hydrochloride, belonging to the field of pharmaceutical synthesis. The method uses 5-acetylsalicylic acid as a starting material, obtains 3-bromo-5-(2-bromoacetyl)-2-hydroxybenzamide through bromination, then undergoes a substitution reaction with 1-methyl-3-phenylpropylamine, followed by hydrogenation reduction, and finally salt formation to obtain labetalol hydrochloride. The method provides a high conversion rate and few byproducts by using the synthesized 3-bromo-5-(2-bromoacetyl)-2-hydroxybenzamide intermediate to replace 5-bromoacetylsalicylic acid. The obtained product can be directly used in the next reaction, followed by substitution and reduction to obtain the final product. This method is low-cost, high-yield, simple, and controllable, facilitating industrialized production and showing excellent application prospects.

The application discloses a long carbon chain polyamide continuous salting method and system, and the method comprises the following steps: mixing a long carbon chain binary acid dispersion liquid I and a long carbon chain binary amine dispersion liquid II in a mixer, and then feeding the mixture into a reaction kettle to obtain a reaction product; the reaction product is divided into two streams, a first stream of the reaction product is circulated back into the reaction kettle, and a second stream of the reaction product is taken out. In the method, the conversion rate of the reaction kettle binary acid is greater than 99.50%, the particle size of the obtained solid salt particles is located in the range of 20-40 microns, the particle size distribution is narrow, and the impurity content in the solid salt is less than 0.20 wt%.

The invention discloses a preparation method of litamilast, which comprises the following steps: a) carrying out primary carbonyl insertion reaction on a compound shown in a formula (II) and a compound shown in a formula (III) to obtain a compound shown in a formula (IV); b) performing trifluoromethanesulfonylation on the compound in the formula (IV) to obtain a compound in a formula (V); c) carrying out secondary carbonyl insertion reaction on the compound shown in the formula V and amino acid shown in the formula VI to obtain a compound VII, and salifying the compound VII and dicyclohexylamine VIII to obtain a litamilast dicyclohexylamine salt IX; and d) dissolving and dissociating the litamilast dicyclohexylamine salt (IX), acidifying and crystallizing to obtain a litamilast crude product, and refining to obtain a litamilast (I) finished product. The method has the advantages of short steps, mild conditions, avoidance of frequent use of group protection and deprotection, avoidance of use of toxic reagents or toxic gases, great reduction of the occurrence of side reactions, reduction of the generation of impurities, simple post-treatment and higher purity.

The invention relates to a preparation method of bis (fluorosulfonyl) imine salt. The method comprises the following steps: adding anhydrous ammonium fluoride and cation source fluoride into an organic solvent, and then dropwise adding a sulfonyl chloride solution; and after dropwise adding, continuously stirring, and carrying out reflux reaction for 5-20 hours to obtain the bis (fluorosulfonyl) imine salt. According to the method, hydrogen fluoride and sulfonyl fluoride are not adopted, meanwhile, the adverse effect of water of water-containing metal hydroxide or metal carbonate in the bis (fluorosulfonyl) imide salification reaction process on product purification is avoided, and efficient, low-cost and large-scale preparation of the bis (fluorosulfonyl) imide salt is achieved.

The application belongs to the field of pharmaceutical preparations and discloses a soothing pharmaceutical preparation and a preparation method thereof. The preparation method comprises the following steps: firstly, preparing synthetic naphazoline hydrochloride by using compound 1 containing a cyano group, wherein a composite solvent composed of toluene and ethyl acetate is used for condensation reaction in the synthesis process, and dilute hydrochloric acid is used for salt formation; secondly, preparing synthetic pheniramine maleate by using compound 2 containing a halogen group and compound 3 containing a cyano group, wherein a weak base catalyst is used for condensation reaction in the synthesis process; finally, adding functional additives, naphazoline hydrochloride and pheniramine maleate into water, stirring and dissolving, and filling to obtain the soothing pharmaceutical preparation, wherein the pH of the soothing pharmaceutical preparation is 5.7-6.3. The soothing pharmaceutical preparation prepared by the above method can effectively avoid the adverse influence of impurities in naphazoline hydrochloride and pheniramine maleate on the soothing effect.

The invention discloses a synthetic method of tea geometrid sex pheromone (3Z, 6Z, 9Z)-octadecatriene, which comprises the following steps: carrying out bromination on cis-3-hexene-1-alcohol in a bromination system, and carrying out salt forming reaction on the brominated cis-3-hexene-1-alcohol and triphenylphosphine to obtain cis-3-hexenyl triphenylphosphonium bromide; the preparation method comprises the following steps: generating an alkynyl metal intermediate from 3-butyne-1-alcohol under the action of an organic metal reagent, and carrying out alkylation reaction on the alkynyl metal intermediate and n-octane bromide to obtain 3-dodecanol; carrying out hydrogenation reaction under the action of a catalyst, and then carrying out oxidation reaction under the action of an oxidizing agent to obtain cis-3-dodecenal; the preparation method comprises the following steps: dispersing cis-3-hexenyl triphenyl phosphonium bromide in an ether solvent, and carrying out Wittig reaction on the cis-3-hexenyl triphenyl phosphonium bromide and cis-3-dodecenal under the action of alkali to obtain the (3Z, 6Z, 9Z)-octadecatriene. The synthesis method only needs six-step reaction, the reaction condition is mild, the raw materials are cheap and easy to obtain, the yield is high, and large-scale production is easy.

This invention provides a method for preparing a sacubitril intermediate, relating to the field of pharmaceutical synthesis technology. Using (2R)-4-nitro-2-methyl-butyrate ethyl ester and 4-bromomethylbiphenyl as initial raw materials, the method involves condensation reaction, hydrogenation reduction reaction, acidification, amino protection reaction with BOC anhydride, hydrolysis, salt formation and resolution reaction with R(+)-α-methylbenzylamine, and acidification to liberate the sacubitril intermediate. The preparation method provided by this invention is simple, easy to operate, has a high yield of the target product (36.5% overall yield in Example 1), high purity, low raw material cost, low production cost, and generates minimal waste, making it suitable for industrial production.

The invention discloses a synthesis method of a high-content lactofen active compound, and belongs to the technical field of pesticide production. According to the technical scheme, the method comprises the following steps: S1, salifying: dissolving an acifluorfen crude product in an organic solvent, adding a sodium hydroxide aqueous solution, heating to 100-120 DEG C, reacting for 3-4 hours to generate acifluorfen sodium salt, adding water for extraction at the extraction temperature of 80-90 DEG C, and collecting a water phase part; the mass ratio of the acifluorfen crude product to the organic solvent to the sodium hydroxide aqueous solution is 1: (1.5-3.3): (1.8-2.6); s2, acid precipitation: adding the water phase part into an acid precipitation kettle, adding hydrochloric acid to adjust the pH value to 1-2, keeping the temperature in the kettle at 45-55 DEG C, carrying out heat preservation reaction for 5-6 hours, adding an organic solvent, extracting, layering, taking the organic phase part, and dehydrating to obtain a purified acifluorfen organic phase; and S3, condensation. The method disclosed by the invention can be suitable for industrial production and can be used for obtaining high-yield lactofen at the same time.

The application relates to the technical field of medicine synthesis, and discloses a preparation method of an avibactam intermediate, which comprises the following steps: taking AVI-SM-0 as a starting material, and sequentially performing esterification reaction, Boc protection, ring-opening addition reaction, imidization reaction, deprotection ring closure reaction, reduction reaction and salt formation to obtain the avibactam intermediate. The process is simple in operation, low in cost, high in stability, and the product quality meets the registration declaration requirements of avibactam.

The invention discloses a preparation method of basic nickel carbonate in the field of inorganic material preparation. The method comprises the following steps: mixing a nickel sulfate solution and a sodium carbonate solution in a reaction kettle, adding a specific molecular regulating agent, carrying out precipitation reaction at a controlled temperature, aging, filtering, washing and drying to obtain sphere-like basic nickel carbonate with uniform granularity and high purity. The regulating agent is synthesized by the following steps: firstly, protecting hydroxyl of (S)-tert-leucinol by using tert-butyldimethylsilyl chloride; then carrying out Michael addition with 2-(trifluoromethyl) acrylic acid under the action of a basic catalyst; carrying out secondary Michael addition on the obtained product and 2-dodecenoic acid to introduce a hydrophobic long chain; removing a silyl ether protecting group to release hydroxyl; and finally salifying with sodium hydroxide to obtain the target regulating agent. The molecular regulating agent can effectively control the precipitation process through steric hindrance and coordination, significantly improves the particle size distribution and purity of the product, and is simple in preparation process and suitable for industrial production.

The invention discloses a preparation method of renobactam, which comprises the following steps: by taking (2S, 5R)-5-((benzyloxy) amino) piperidine-2-carboxylic acid ethyl ester oxalate as a starting raw material, carrying out ester hydrolysis, Boc protection, condensation, deprotection, ring closing, debenzylation, Boc protection, sulfonation, ammonium salt formation and deprotection to obtain the renobactam. The preparation method has the advantages of simple operation, few steps, simple post-treatment, good reaction selectivity, high purity, high yield and the like, and is suitable for industrial production.

The invention belongs to the technical field of chemical synthesis, and discloses a cefotaxime sodium synthesis method based on one-step salification of a mixed solvent system and sodium isooctanoate. The method comprises the following steps: by taking 7-aminocephalosporanic acid (7-ACA) and 2-(2-aminothiazole-4-yl)-2-(methoxyimino) acetoxyimino ethyl acetate (AE active ester) as raw materials, in a dichloromethane-methanol mixed solvent, completing a condensation reaction through triethylamine catalysis, directly dropwise adding a sodium isooctanoate acetone solution to realize salification in one step, and carrying out post-treatment to obtain the 7-aminocephalosporanic acid (7-ACA)-2-(methoxyimino) acetoxyimino ethyl acetate (AE active ester)-2-(methoxyimino) acetoxyimino ethyl acetate (AE active ester). The cefotaxime acid intermediate does not need to be separated; and performing low-temperature washing and accurate drying subsequently to obtain a cefotaxime sodium finished product. According to the method, the defects that in the prior art, a two-step method needs intermediate separation and a one-pot method needs alkaline degradation are overcome, the production period is shortened to be smaller than or equal to 8 h, the total yield is larger than or equal to 92%, the HPLC purity is larger than or equal to 99.6%, the wastewater COD is smaller than or equal to 2000 mg / L, solvent residues meet the ICH Q3C standard, and the method has the advantages of industrial feasibility and environmental protection.

This invention belongs to the field of biomedical technology and discloses a method for preparing furazolidone hydrochloride. This method involves introducing nicotinamide or saccharin as a co-crystal forming agent during the salt formation crystallization process. Under specific solvent systems and pH conditions, crystallization is carried out through programmed cooling to obtain a pharmaceutical co-crystal with a two-dimensional supramolecular hydrogen bond network structure. The obtained product is blocky or spherical, with good flowability, high chemical stability, and gradual and controllable dissolution. This method is feasible, the product meets pharmaceutical requirements, and it improves formulation performance and drug safety.

The invention discloses a synthetic method of perfluoroalkoxy methylene vinyl ether, which comprises the following steps of: 1, reacting alkyl fluoroformate with halogenated olefin under the action of an auxiliary agent to generate halogenated alkyl ether, and performing dehalogenation reaction to generate perfluoroalkoxy methylene vinyl ether; the method II comprises the following steps: reacting alkyl fluoroformate with hexafluoropropylene oxide under the action of an auxiliary agent to generate alkoxy propionyl fluoride, and carrying out salification and decarboxylation reaction to generate perfluoroalkoxy methylene vinyl ether (RfOCF2OCF = CF2); the auxiliary agent is metal fluoride or fluoro quaternary ammonium salt. In the first method and the second method, the alkyl fluoroformate and the halogenated olefin or the hexafluoropropylene oxide need to react under the action of the aid (metal fluoride or fluoro quaternary ammonium salt), so that the safety problem caused by direct use of fluorine gas is avoided, and the conversion rate of the trifluoromethyl fluoroformate and the yield and selectivity of the product can be improved.

The invention relates to a preparation method of miloabalin or meloabalin besylate, and belongs to the technical field of synthesis of drug intermediates. In order to solve the problem of impurities easy to produce cyclization in the prior art, the invention provides the preparation method of the miloabalin or the meloabalin besylate, which comprises the following steps: in the presence of a catalytic amount of noble metal catalyst and Boc2O, carrying out hydrogenation reduction and protective group loading reaction on a compound shown in a formula III to obtain a compound shown in a formula IV; carrying out selective ester hydrolysis reaction under the action of a selective ester hydrolysis reagent to obtain an intermediate compound as shown in a formula V; carrying out decarboxylation reaction under the action of a selective decarboxylation catalyst to obtain an intermediate; carrying out salt forming reaction with organic amine to obtain a compound as shown in a formula VII; and then carrying out a deprotection reaction to obtain the miloabalin. And during synthesis of the meloabalin besylate, the meloabalin besylate and benzenesulfonic acid are subjected to a salt forming reaction to obtain the meloabalin besylate. The purity of an intermediate product in each step reaches 98.5% or above, and the yield reaches 90% or above.