33 results about "Triethyl orthoformate" patented technology

The invention relates to the field of organic chemical synthesis, in particular to a synthetic method and application of pyrimidone compounds. The invention provides a synthesis method, reactants are o-amino heterocyclic formamide and triethyl orthoformate respectively, a solvent system is a hexafluoroisopropanol solvent, and a product is a heterocyclic pyrimidone compound. The reaction does not need strong acid or strong alkali conditions, does not need additional reducing agents or oxidizing agents, does not need transition metal catalysis, is economical and practical, the reaction conditions are relatively mild, and the synthesized pyrimidone compound has a good antibacterial effect.

The application provides a preparation method of finerenone and intermediates thereof. The application discloses a preparation method of a finerenone intermediate 5, which comprises the following steps: step 1: in an organic solvent, a resolution reaction is carried out between a finerenone intermediate 2 and D-tartaric acid diphenyl ester to obtain a resolution salt, then an acid-base reaction is carried out between the resolution salt and a base to obtain the finerenone intermediate 3; step 2: in an organic solvent, a nucleophilic substitution reaction is carried out between the finerenone intermediate 3 and triethyl orthoformate in the presence of an acid to obtain a finerenone intermediate 4; step 3: in a solvent, a hydrolysis reaction is carried out between the finerenone intermediate 4 to obtain the finerenone intermediate 5. The preparation method has the advantages of short reaction steps, high total reaction yield, simple and safe operation, simple post-treatment steps, high product purity, low production cost and suitability for industrial production.

The preparation method comprises the following steps: dissolving a compound in a formula 1 and a compound in a formula 2 in a solvent, adding piperidine and acetic acid, and carrying out carbon-carbon coupling to synthesize a compound in a formula 3; dissolving the compound in the formula 3 and the compound in the formula 4 in a solvent, and performing ring closing to synthesize a compound in a formula 5; dissolving the compound as shown in the formula 5 into a solvent, adding triethyl orthoformate, and performing alkylation reaction under the catalysis of acid to synthesize a compound as shown in a formula 6; dissolving the compound of formula 6 in a solvent, adding DDQ, and synthesizing a compound of formula 7; dissolving the compound as shown in the formula 7 in a solvent, and performing NaOH hydrolysis to synthesize a compound as shown in a formula 8; dissolving the compound as shown in the formula 8 into a solvent, and carrying out ammonification reaction under the action of CDI and hexamethyldisilazane to synthesize a compound as shown in a formula 9; and dissolving the compound shown in the formula 9 into a solvent, and carrying out reductive resolution under the action of catalysts A and B to synthesize the fenerenone shown in the formula 10. The preparation method of the fenerenone has the advantages of high chiral selectivity, no need of chromatographic column separation, high yield, low cost and the like.

This application relates to a UV-3 ultraviolet absorber and its preparation method, belonging to the field of chemical synthesis technology. The preparation method employs a one-pot process, in which benzocaine reacts with triethyl orthoformate in xylene solvent. This step utilizes reactive distillation coupling control, continuously removing the generated alcohol distillate through a distillation separation device to promote reaction equilibrium shift, obtaining a xylene solution of the intermediate NET. Subsequently, the solution is heated to a reaction temperature of 135–145°C, and benzyl chloride is added dropwise for N-alkylation, while a tail gas absorption device absorbs byproduct gases. The reaction slurry is then cooled for crystallization, solid-liquid separation, and drying to obtain the UV-3 product. This invention simplifies the production process through a one-pot process, avoids the use of toxic DMF solvent, and solves the technical problem of raw material residues leading to subsequent side reactions in the one-pot process through reactive distillation coupling control, resulting in a final product with high purity and high yield.

The present invention discloses a method for synthesizing a pevonedistat intermediate, comprising the following steps: adding compound I, triethyl orthoformate and a catalyst into a reaction vessel to react and generate compound II; performing a crystallization operation and filtering the reaction solution to obtain a crude compound II; adding the crude compound II and (S)-(+)-1-aminoindene into a solvent to react and generate compound III; adding a nucleophilic substance into the reaction solution, performing a reflux reaction, and causing compound III to undergo a Dimroth rearrangement to generate a crude compound IV; and recrystallizing the crude compound IV to obtain a refined compound IV. The method for synthesizing the pevonedistat intermediate provided by the present invention uses compound I as a raw material to generate N-(S)-(+)-1-aminoindene as a pevonedistat intermediate in two steps. 6 -Indenyl-7-deazaadenine; the synthesis method shortens the production cycle, has mild synthesis conditions, and low raw material prices, which is conducive to industrial production.

The invention relates to the field of preparation of fluxapyroxad, and discloses a preparation method of fluxapyroxad. The preparation method comprises the following steps: 1, heating 4, 4-difluoro-3-oxobutanamide and triethyl orthoformate in an organic solvent for reaction to obtain a compound a; 2, adding the compound a into a mixed solution of methylhydrazine and an organic solvent under an ice bath condition, and then reacting under a heating condition; and after the reaction is completed, evaporating out the solvent and concentrating to obtain a compound b. 3, under the action of an alkaline reagent and a metal catalyst, adding the compound b and 2-bromochlorobenzene into an organic solvent, and heating for condensation reaction to generate a compound c; and 4, adding the compound c and 3, 4, 5-trifluorophenylboronic acid into a solvent to carry out Suzuki reaction under the protection of nitrogen and the action of an alkaline reagent and a metal catalyst. And after the reaction is completed, evaporating out the solvent and concentrating to obtain the fluxapyroxad. The method disclosed by the invention has the characteristics of overall economy, environmental protection, safety and high efficiency, and also has relatively strong industrial application potential.

The application discloses a method for asymmetrically catalytically synthesizing naphthyridine carboxamide drug finerenone, and belongs to the technical field of organic synthesis. In the first step, compound 1 is reacted with S-1-phenylethanol in an organic solvent to generate intermediate 2; in the second step, compound 2 is reacted with 4-cyano-2-methoxybenzaldehyde in an organic solvent to generate intermediate 3; in the third step, compound 3 is reacted with 4-amino-5-methylpyridin-2-ol in the presence of a chiral catalyst in an organic solvent to generate crude intermediate 4, the crude intermediate 4 is then salified by adding a resolving agent, and after being freed, the intermediate 4 is obtained; in the fourth step, compound 4 is reacted with triethyl orthoformate in an organic solvent under the catalysis of an acid to generate intermediate 5; in the fifth step, compound 5 is catalytically hydrogenated in the presence of a palladium catalyst to generate intermediate 6; and in the sixth step, compound 6 is reacted with hexamethyldisilazane in the presence of a condensing agent, and after treatment, the product I is obtained. The application provides an improved preparation method for finerenone and has the prospect of industrial production.

The invention relates to moisture-proof plywood and a preparation method thereof, and belongs to the technical field of plywood processing.The moisture-proof plywood is obtained by gluing three layers of veneers through an adhesive, and the fiber directions of the adjacent layers of veneers are perpendicular to each other; the adhesive is composed of a liquid adhesive and a filling agent; wherein the liquid glue is prepared from the following raw materials in parts by weight: 40 to 45 parts of isocyanate, 6 to 12 parts of dioctyl phthalate, 3 to 6 parts of triethyl orthoformate, 12 to 16 parts of epoxidized soybean oil and 1 to 3 parts of polydimethylsiloxane; the filling agent is prepared from the following raw materials in parts by weight: 35-55 parts of wood flour, 10-20 parts of calcium carbonate, 30-35 parts of aluminum stearate and 5-10 parts of carbon nanotubes. The fiber directions of the adjacent layers of veneers are perpendicular to each other, the veneers can be prevented from being broken in the fiber directions, the adhesive is prepared in the mode that the liquid adhesive and the filler are combined, the filler provides a framework for the liquid adhesive, and the viscosity, the leveling property and other construction performance of the adhesive can be controlled.

The invention relates to the technical field of biological medicines, in particular to a preparation method of an intermediate androstane-17alpha-methyl-17beta-hydroxy-3-ketone of steanoconazole, and belongs to the technical field of biological medicines. The method comprises the following steps: by taking 4-androstenedione as a raw material and p-toluenesulfonic acid as a catalyst, carrying out 3-position ketene etherification protection on the 4-androstenedione and triethyl orthoformate to obtain a compound shown in a formula III; then carrying out Grignard addition on the compound shown in the formula IV and methyl magnesium bromide and carrying out in-situ silyl ether protection to obtain a compound shown in the formula IV; carrying out normal-pressure hydrogenation to obtain a compound as shown in a formula V; and carrying out acid hydrolysis, neutralization, devitrification and recrystallization through a one-pot method to obtain a high-purity target product shown in the formula I. The method is characterized in that the problems of unstable key intermediate, complex process, low yield and the like are successfully solved through in-situ silyl ether protection and one-pot method operation, and the method has the outstanding advantages of short route, safety in operation, high yield, good product purity and suitability for industrial production.

This invention proposes a method for preparing dehydroepiandrosterone (DHEA), comprising the following steps: S1, dissolving 4-androstenedione in acetic anhydride to obtain a first material, which is then pumped separately into an acetylation microchannel reactor with quaternized GO-phosphotungstic acid catalyst supported on the inner wall for reaction with acetyl chloride; S2, mixing triethyl orthoformate with anhydrous ethanol to obtain a second material, which is then pumped separately into a ketal microchannel reactor with niobium oxide / γ-CD-phosphotungstic acid catalyst supported on the inner wall of the ketal microchannel reactor; S3, dehydrating the effluent from step S2 and adjusting the pH to 7-8, then pumping separately into a reduction microchannel reactor with an ethanol solution containing sodium borohydride for reduction reaction; S4, adding hydrochloric acid to the effluent from step S3 and adjusting the pH to 2-3 to obtain a hydrolysate; evaporating the solvent from the hydrolysate, filtering and drying to obtain DHEA. The supported heteropolyacid composite membrane used in this invention exhibits high catalytic efficiency, high yield, and excellent quality.

The invention relates to a preparation method of medroxyprogesterone acetate. The preparation method of medroxyprogesterone acetate comprises the following steps: mixing 17alpha-hydroxyprogesterone with glacial acetic acid, acetic anhydride and a first catalyst for first reaction to prepare an intermediate 1; mixing the intermediate 1 with tetrahydrofuran, ethanol, triethyl orthoformate and a second catalyst to carry out a second reaction, then adding formaldehyde and N-methylaniline to carry out a third reaction, then adding hydrochloric acid and water to carry out a fourth reaction, and collecting a crude product of an intermediate 2; and preparing the medroxyprogesterone acetate through a series of refining steps. According to the preparation method, the dosage of the palladium-carbon catalyst is small, the cost can be obviously reduced, and the product is lower in impurity content and higher in purity.

The utility model discloses a reactor for preparing triethyl orthoformate through alcoholysis reaction. Comprising a bottom plate, a tank body fixedly connected to the upper end of the bottom plate, a feeding unit arranged at the upper end of the tank body, an air inlet unit arranged on the side wall of the tank body, a discharging unit arranged on the lower portion of the side wall of the tank body, a mixing mechanism arranged at the upper end of the bottom plate, a second fixing box arranged on the lower portion of the inner wall of the tank body and a vertical cylinder fixedly connected to the upper end of the second fixing box. The hopper body is fixedly connected to the upper end of the vertical cylinder, the inner tank is fixedly connected to the inner wall of the second fixing box, the second through hole is formed in the lower end of the inner tank in a penetrating mode, the vertical pipes are fixedly connected to the upper end of the inner tank, and the third through holes are formed in the peripheral walls of the vertical pipes in a penetrating mode. The device has the advantages that the gas-liquid mass transfer can be efficiently enhanced, the removal of light components is promoted, the semi-continuous efficient reaction is realized, and the catalyst is convenient to recycle.

The invention provides a preparation method of 17 [alpha]-hydroxyprogesterone, which comprises the following steps: S1, putting 17 [beta]-cyano-17 [alpha]-hydroxy-4-androstene-3-ketone, ethylene glycol, triethyl orthoformate and a beta-CD-SO3H / SiO2 catalyst into a reaction kettle, and carrying out a ketal reaction, so as to obtain 17 [beta]-cyano-5-androstene-17-ol-3, 3-ethylene ketal; and S2, dissolving the 17 [beta]-cyano-5-androstene-17-ol-3, 3-ethylene ketal in an organic solvent, adding lithium chloride and a benzene solution containing methyl zinc, carrying out a reaction, and after the reaction is finished, carrying out acid hydrolysis to obtain the 17 [alpha]-hydroxyprogesterone. The solid acid catalyst beta-CD-SO3H / SiO2 coated hydrophobic SiO2 is adopted, so that the problems of more side reactions, low purity and yield and the like of liquid acid are effectively solved, and the purity and yield of the final product respectively reach 98.8% and 92.9%.

The invention discloses a method for preparing a fenerenone tablet. The method comprises the following steps: step 1, taking a compound FNLT-8 and a compound FNLT-9 as raw materials, and coupling to obtain a compound FNLT-7; 2, the compound FNLT-7 and a compound FNLT-10 are subjected to a reaction, and a compound FNLT-6 is obtained; 3, the compound FNLT-6 is subjected to ethylation through triethyl orthoformate, and a compound FNLT-5 is obtained; 4, performing reflux reaction on the compound FNLT-5 under the action of a catalyst, and finally performing tartaric acid resolution to obtain a compound FNLT-4; 5, further reacting the compound FNLT-4 to obtain a compound FNLT-3; 6, hydrolyzing the compound FNLT-3 under an alkaline condition to obtain a compound FNLT-2; 7, the compound FNLT-2 is split through a splitting reagent, and a compound FNLT-1 is obtained. According to the method disclosed by the invention, one-step synthesis of FNLT-9 to FNLT-6 in an original process is changed into two-step synthesis, the yield and the content are improved, the product content is improved from FNLT-4 to FNLT-2 by adopting an optimized process, and meanwhile, the product content is improved from FNLT-2 to FNLT-1 by adopting a resolution reagent for resolution, so that the cost is reduced, and the method is suitable for industrial production.

The invention discloses a synthesis method of a diene liquid crystal monomer, which comprises the following steps: S1, Grignard addition reaction: carrying out Grignard addition reaction on substituted cyclohexyl N-methoxy-N-methyl benzamide and a substituted cyclohexyl methyl chloride Grignard reagent to obtain a ketone intermediate; s2, the ketone intermediate sequentially reacts with 5, 5-dibromobarbituric acid for a bromination reaction, then sodium formate is added into an alcohol solvent for a hydroxylation reaction, then sodium borohydride is added for a reduction reaction, and a vicinal diol intermediate is obtained; and S3, carrying out an orthoformate reaction on the vicinal diol intermediate obtained in the step S2 and triethyl orthoformate in a fluorine-containing alcohol solvent, then heating to reflux, and carrying out an elimination reaction to obtain the target diene liquid crystal monomer. According to the invention, a traditional double bond construction strategy of multiple Wittig reactions is abandoned, a new synthesis route which takes the Grignard reaction as a starting point and finally constructs a diene structure by a one-pot method through a low-temperature orthoformate / elimination reaction carried out in a specific fluorine-containing solvent is designed, the route is simple, the total yield is high, and the overall cost is lower.

The invention relates to the technical field of pharmaceutical chemicals, in particular to a preparation method of cholesterol. The method comprises the following steps: 3-position carbonyl ketal protection reaction: uniformly mixing BA, ethylene glycol, p-toluene phosphoric acid and triethyl orthoformate, controlling the temperature to be 40-60 DEG C, reacting for 2-8 hours, cooling to-10-10 DEG C, controlling the temperature to be 1-5 hours, filtering, and drying at 40-70 DEG C to obtain a compound IM1; oxidation of 21-site hydroxyl into aldehyde; s3, carrying out Grignard reaction on the 21-site aldehyde group; carrying out a reaction of oxidizing 21-site hydroxyl into ketone; carrying out a reaction of reducing 21-site carbonyl into methylene; carrying out 3-position carbonyl ester forming reaction; the method disclosed by the invention has the characteristics of good selectivity, low cost and small pollution, and the method is stable and easy to realize industrial production.

The invention discloses a preparation method of a drug intermediate 8-(2-benzamido) sodium caprylate, which comprises the following steps: in the presence of a solvent A or a catalyst, reacting salicylamide with triethyl orthoformate to obtain a compound I-1; (2) in the presence of alkali and a solvent B, carrying out substitution reaction on the compound I-1 and 8-bromocaprylic acid tert-butyl ester to obtain a compound I-2; (3) in the presence of an acid and a solvent C, carrying out a deprotection reaction on the compound I-2 to obtain a compound I-3; and (4) in the presence of a solvent D, reacting the compound I-3 with alkali salt of sodium to obtain the compound I. The method provided by the invention has the advantages of high yield, high selectivity, low production cost, few byproducts, easiness in industrial production and environmental friendliness.

The invention provides a preparation method of fenerenone and an intermediate thereof. The invention discloses a preparation method of a fenerenone intermediate 5, which comprises the following steps: step 1, in an organic solvent, carrying out resolution reaction on a fenerenone intermediate 2 and D-diphenyl tartrate to obtain a resolution salt, and then carrying out acid-base reaction on the resolution salt and alkali to obtain a fenerenone intermediate 3; 2, in an organic solvent, in the presence of acid, carrying out nucleophilic substitution reaction on the fenerenone intermediate 3 and triethyl orthoformate to obtain a fenerenone intermediate 4; and step 3, in a solvent, carrying out a hydrolysis reaction on the fenerenone intermediate 4 to obtain the fenerenone intermediate 5. The preparation method provided by the invention has the advantages of short reaction steps, high reaction total yield, simple and safe operation, simple post-treatment steps, high purity of the prepared product, low production cost and suitability for industrial production.

The application provides a preparation method of 17alpha-hydroxyprogesterone, which comprises the following steps: S1, 17beta-cyano-17alpha-hydroxy-4-androsten-3-ketone, ethylene glycol, triethyl orthoformate and a beta-CD-SO3H / SiO2 catalyst are put into a reaction kettle to perform a ketal reaction, so that 17beta-cyano-5-androsten-17-ol-3,3-ethylene glycol ketal is obtained; S2, the 17beta-cyano-5-androsten-17-ol-3,3-ethylene glycol ketal is dissolved in an organic solvent, lithium chloride and a methyl zinc-containing benzene solution are added to react, and after the reaction is completed, 17alpha-hydroxyprogesterone is obtained through acid hydrolysis. The solid acid catalyst beta-CD-SO3H / SiO2@hydrophobic SiO2 is adopted, so that the problems of more side reactions, lower purity and lower yield caused by liquid acid are effectively solved, and the purity and the yield of the final product reach 98.8% and 92.9% respectively.

The utility model discloses a distillation and purification device for triethyl orthoformate. Comprising a bottom plate, a bearing block fixedly connected to the upper end of the bottom plate, a distillation still fixedly connected to the upper end of the bearing block, a groove body formed in the peripheral wall of the distillation still in a penetrating mode, a sliding door hinged to the inner wall of the groove body, a feeding assembly arranged on the peripheral wall of the distillation still, a steam output assembly arranged at the upper end of the distillation still and a discharging assembly arranged at the lower end of the distillation still. The first bearing ring is fixedly connected to the middle part of the inner wall of the distillation kettle; the movable ring is placed at the upper end of the first bearing ring; the fixed cylinder is arranged on the inner wall of the movable ring in a sliding manner; the separation cylinder is fixedly connected to the lower end of the movable ring; the guide cylinder is fixedly connected to the upper end of the fixed cylinder; the air guide assembly is arranged at the upper part of the inner wall of the distillation kettle. The utility model has the advantages that the internal airflow can be actively guided and adjusted, the mass and heat transfer efficiency is high, and the cleaning and maintenance are convenient.

The present invention relates to a preparation method of marbofloxacin. The preparation method of the present invention is that under alkaline conditions, ethyl 2,3,4,5-tetrafluorobenzoate reacts with acetonitrile to prepare intermediate (I), intermediate (I) reacts with triethyl orthoformate and acetic anhydride and then reacts with formylhydrazine to prepare intermediate (II), intermediate (II) cyclizes under alkaline conditions to prepare intermediate (III), intermediate (III) is hydrolyzed with base and then cyclizes with formaldehyde to prepare intermediate (IV), and intermediate (IV) reacts with N -methylpiperazine and then through N -methylation to prepare marbofloxacin. The raw materials of the present invention are cheap, the reaction conditions are mild, the operation is easy, the product yield and purity are high, and it is suitable for industrial production.

The application belongs to the technical field of medicine synthesis, and particularly relates to a gemigim intermediate compound and a preparation method thereof. The gemigim new intermediate compound is obtained by reacting alpha-cyanoacetamide, triethyl orthoacetate and triethyl orthoformate as starting materials. The new intermediate is cyclized to obtain a gemigim key intermediate compound 3-cyano-4-methoxy-2(1H)-pyridinone. The new intermediate synthesis method provided by the application is simple, triethyl orthoformate is used as a 'one-carbon unit' donor, the reagent only produces ethanol in the cyclization process, the use of DMF-DMA can be effectively avoided, and then the generation of dimethylamine gas or its acetate salt is avoided, so that the reaction operation is safer and more environmentally friendly.

The invention relates to the technical field of pharmaceutical chemicals, in particular to a preparation process of hydrocortisone acetate. The preparation process comprises the following steps: carbonyl protection reaction: sequentially adding ethylene glycol, triethyl orthoformate and a compound 1 into a reaction flask, then adding p-toluenesulfonic acid, adding water for crystallization, filtering and drying to obtain a compound 2; a reduction hydrolysis reaction; and a replacement reaction: adding the compound 3 into the reaction solvent, adding potassium acetate, carrying out a heating reaction, after the reaction is completed, cooling, adding water for crystallization, filtering to obtain a crude product of hydrocortisone acetate, dissolving with dichloromethane and water for desalting, washing with water for layering, concentrating to be dry, crystallizing with an alcohol solvent, and discharging to obtain a refined product of hydrocortisone acetate. According to the present invention, the method has characteristics of simple and convenient operation, high product yield, and high purity, and the method of cooling after the reaction, adding water, precipitating, filtering, removing most of the impurities, dissolving to remove the salt, and carrying out alcohol refining and discharging is provided, such that the method has characteristics of simple and convenient operation, and the obtained product has characteristics of high yield and high purity.

The invention discloses a method for preparing fenerenone, which comprises the following steps of: (a) synthesizing a compound shown as a formula 3 by taking a compound shown as a formula 1 and a compound shown as a formula 2 as raw materials; (b) reducing the compound in the formula 3 under the action of a catalyst A and a catalyst B to obtain a compound in a formula 4; (c) synthesizing a compound shown in a formula 5 from the compound shown in the formula 4 and triethyl orthoformate under the catalysis of acid; (d) performing alkaline hydrolysis on the compound in the formula 5 to synthesize a compound in a formula 6; and (e) synthesizing the compound shown in the formula 6 into fenerenone shown in a formula 7 under the action of hexamethyldisilazane and CDI. According to the preparation method of the finerenone, chiral inversion is carried out from the intermediate, then the required chiral intermediate is obtained, then the finerenone is synthesized from the intermediate, splitting is carried out through the catalyst, half of chiral isomers cannot be lost, and the catalyst enables all raw materials to be converted into the required chiral configuration.

The invention relates to a quinoline cyanine analogue near-infrared fluorescent dye and a preparation method thereof. The method comprises the following steps: refluxing 4-methylquinoline and halogenated hydrocarbon in an organic solvent, cooling, adding tert-butyl methyl ether for precipitation, carrying out suction filtration, and washing with tert-butyl methyl ether; and refluxing the product, N, N '-dibenzamidine and triethyl orthoformate in an ethanol solvent, cooling, carrying out reduced pressure spin-drying on the solvent, adding ethyl acetate to wash the remaining solid, carrying out suction filtration, leaching with ethyl acetate, suspending ethyl chromate in anhydrous and oxygen-free tetrahydrofuran, adding methyl magnesium bromide under the protection of N2, then adding methanol for quenching, and carrying out reduced pressure removal on the solvent to obtain the ethyl chromate. Obtaining a crude product; and eluting the crude product with ethyl acetate, dissolving the crude product in dichloromethane, adding triethylamine, stirring overnight at room temperature, after the reaction is finished, spin-drying the solvent, and purifying the product through column chromatography to obtain the quinoline cyanine analogue near-infrared fluorescent dye. The dye is synthesized into the dye with excitation emission wavelengths in near infrared (more than 700nm), can effectively avoid biological background fluorescence interference, and is large in molar extinction coefficient and good in fluorescence property.

The invention relates to a preparation method of ursolic acid derivatives. According to the invention, the structure-function relationship is deeply researched, the chemical modification method of ursolic acid is comprehensively considered, the efficient and economical synthesis and preparation method is obtained by taking substituent-free aniline, triethyl orthoformate and methyl carbazate as raw materials, the yield of UA770 obtained by the method is high, the method is simple and easy to implement, and industrial production of ursolic acid derivatives is easy to realize. Meanwhile, the UA770 can obviously down-regulate the expression of NLRP3 / GSDMD signal axis related protein, relieve pyroptosis of liver cells, reduce the MDA content in liver tissues, increase the SOD activity and improve the antioxidant capacity of the liver cells, so that the UA770 plays a role in protecting acute liver injury.

The invention discloses a synthesis method of a flurobixafen metabolite. The synthesis method comprises the following steps: carrying out condensation reaction on ethyl difluoroacetoacetate and triethyl orthoformate to prepare an intermediate A; carrying out cyclization reaction on the intermediate A and hydrazine hydrate to generate an intermediate B; carrying out N-benzylation reaction on the intermediate B and a methoxybenzyl derivative to obtain an intermediate C; performing hydrolysis and acidification reaction on the intermediate C to obtain an intermediate D; reacting the intermediate D with thionyl chloride or oxalyl chloride to obtain an intermediate E; reacting the intermediate E with 2-(3, 4-dichlorophenyl)-4-fluoroaniline to obtain an intermediate F; and carrying out N-benzyl removal reaction on the intermediate F to obtain the flurobixafen metabolite. The method has the advantages of cheap raw materials, mild reaction conditions, simplicity in operation, environmental friendliness, no need of special and expensive catalysts, high yield and the like, and is suitable for industrial production.

This invention relates to the field of refrigerants, specifically to a mixed refrigerant and its preparation method. By weight, the refrigerant comprises 85-95 parts of a basic refrigerant, 1-5 parts of a flame retardant, 1-10 parts of a lubricating oil, and 0.1-0.5 parts of a stabilizer. The basic refrigerant is a mixture of R32, R1234ze(E), and R1234yf in a mass ratio of (18-28):(45-60):(15-25). The stabilizer is a mixture of triethyl orthoformate, triphenyl phosphite, and methylbenzotriazole in a mass ratio of (0.1-0.15):(0.1-0.15):(0.15-0.2). This refrigerant has a low GWP, good flame retardant properties, and good stability.

This invention discloses a method for preparing phenelzine, comprising the following steps: dissolving compounds of formula 1 and formula 2 in a solvent, adding piperidine and acetic acid, and performing carbon-carbon coupling to synthesize compound 3; dissolving compounds of formula 3 and formula 4 in a solvent, performing cyclization to synthesize compound 5; dissolving compound 5 in a solvent, adding triethyl orthoformate, and performing alkylation under acid catalysis to synthesize compound 6; dissolving compound 6 in a solvent, adding DDQ to synthesize compound 7; dissolving compound 7 in a solvent, and hydrolyzing it with NaOH to synthesize compound 8; dissolving compound 8 in a solvent, and performing amination under the action of CDI and hexamethyldisilazane to synthesize compound 9; dissolving compound 9 in a solvent, and performing reduction resolution under the action of catalysts A and B to synthesize phenelzine of formula 10. The method for preparing phenelzine of this invention has advantages such as high chiral selectivity, no need for column chromatography separation, high yield, and low cost.

The invention discloses 3D printing photosensitive resin capable of improving storage stability and a preparation method. The 3D printing photosensitive resin capable of improving storage stability is prepared from the following components in parts by weight: acrylate oligomer, acrylate monomer, polyvinyl alcohol silicate, photoinitiator, antioxidant, triethyl orthoformate, baking soda and pigment. When the photosensitive resin is exposed in air and absorbs water vapor, the triethyl orthoformate is in contact with water to generate hydrolysis reaction, and ethyl formate and ethanol are generated; ethyl formate and baking soda are subjected to a neutralization reaction, acidity is reduced, and ethyl formate is prevented from further generating acetate and ethyl alcohol; and the generated ethanol increases the wettability and eliminates bubbles at the same time. The method has the beneficial effects that water in the photosensitive resin can react with triethyl orthoformate to generate ethanol, so that the water is eliminated, the flocculation phenomenon can be reduced, and part of bubbles can be eliminated; meanwhile, the amount of generated ethanol can be controlled by adjusting the acidity and alkalinity through baking soda.