768 results about "Dimethylaniline N-oxide" patented technology

The present invention relates to a new industrial process for the synthesis of solvate- free 17a-acetoxy-11ss-[4-(N,N-dimethyl-amino)-phenyl]-19-norpregna-4,9-diene-3,20-dione [CDB -2914] of formula (I) which is a strong antiprogestogene and antiglucocorticoid agent. The invention also relates to compounds of formula (VII) and (VIII) used as intermediates in the process. The process according to the invention is the following: i) 3-(ethylene-dioxy)-estra-5(10),9(11)-diene-17-one of formula (X) is reacted with potassium acetilyde formed in situ in dry tetrahydrofuran by known method, ii) the obtained 3-(ethylene-dioxy)-17a-ethynyl-17ss-hydroxy-estra-5(10),9(11)-diene of formula (IX) is reacted with phenylsulfenyl chloride in dichloromethane in the presence of triethylamine and acetic acid, iii) the obtained isomeric mixture of 3-(ethylene-dioxy)-21-(phenyl-sulfinyl)-19-norpregna-5(10),9(11),17(20),20-tetraene of formula (VIII) is reacted first with sodium methoxide in methanol, then with trimethyl phosphite, iv) the obtained 3-(ethylene-dioxy)-17a-hydroxy-20-methoxy-19-norpregna-5(10),9(11),20-triene of formula (VII) is reacted with hydrogen chloride in methanol, then v) the obtained 3-(ethylene-dioxy)-17a-hydroxy-19-norpregna-5(10),9(11l); -diene-20- one of formula (VI) is reacted with ethylene glycol hi dichloromethane in the presence of trimethyl orthoformate and p-toluenesulfonic acid by known method, vi) the obtained 3,3,20,20-bis(ethylene-dioxy)-17a-hydroxy-19-norpregna- 5(10),9(11)-diene of formula (V) is reacted with hydrogen peroxide in a mixture of pyridine and dichloromethane in the presence of hexachloroacetone by known method, vii) the obtained 3,3,20,20-bis(ethylene-dioxy)-17a-hydroxy-5,10-epoxy-19-norpregn-9(11)-ene of formula (IV), containing approximately a 1:1 mixture of 5a,10a- and 5ss,10ss-epoxides, is isolated from the solution and reacted with a Grignard reagent obtained from 4-bromo-N,N-dimethyl-aniline in tetrahydrofuran.

The invention provides N-diethylaminoacetyl-2,6-dimethylaniline derivatives, a preparation method and applications thereof. The structure of the derivatives is represented by the formula (I). The preparation method comprises the following steps: carrying out reactions between N-diethylaminoacetyl-2,6-dimethylaniline and halogenated compounds to obtain a corresponding quaternary ammonium salt intermediate, and then subjecting the quaternary ammonium salt intermediate to react with corresponding 2-methoxyl-4-subsituted phenol derivative raw material so as to obtain the N-diethylaminoacetyl-2,6-dimethylaniline derivatives. The derivatives can be used as a long-acting local anesthetic drug or a pain relieving drug capable of separating the motion and the feeling, can exert a reversible and lasting local anesthetic effect in organism bodies, do not affect motor function in a certain dosage range, and have an ideal retardant effect on separation of motion and feeling.

An adhesive composition that includes a mixture of a cationically polymerizable component, an acidic component, and an initiator is provided. Preferably, the initiator comprises an iodonium salt, a visible light sensitizer, and an electron donor compound, wherein the initiator has a photoinduced potential greater than or equal to that of N,N-dimethylaniline in a standard solution of 2.9x10-5 moles / g diphenyl iodonium hexafluoroantimonate and 1.5x10-5 moles / g camphorquinone in 2-butanone. This adhesive composition is cationically polymerizable and is able to bond to hard tissue and cationic restorative materials upon curing.

The invention relates to an anchoring agent, which is resin mortar for an anchoring agent and the anchoring agent, and is used for anchoring large-diameter anchor cables used in the construction of the support of coal mine roadways and the protection of underground engineering. The resin mortar comprises the following compositions in portion by mass: 800 to 1,200 portions of MG unsaturated polyester resin, 4,000 to 6,000 portions of limestone powder, 3 to 10 portions of dimethylaniline, and 6 to 12 portions of white carbon black, wherein the particle size of the limestone powder is between 80 and 120 meshes. The resin mortar and a curing agent form a bi-component anchoring agent. The anchoring agent can effectively reduce the consistency of the resin mortar, and improve the compressive strength after the solidification of the anchoring agent, thereby realizing the effects during the use such as high adhesive force, low stirring resistance and the like; and the anchoring agent meets the requirement of using large-diameter and high-strength anchor cables in the support of the coal mine roadways, reduces anchoring length, construction time and construction personnel, and improves the production efficiency.

Alkoxy aromatic compounds are conveniently dealkylated to the corresponding phenolic compounds by treatment with aluminum chloride / N,N-dimethyl aniline complex. Aromatic poly O-demethylation is a unique feature of this invention. This process is applicable to the manufacture of polyphenols such as Resveratrol, Oxyresveratrol, Gnetol.

The invention relates to a conducting resin and especially relates to a silver nanowire-filled self-repairing conducting resin and a preparation method thereof. Through an emulsion polymerization method, core-shell structure nano-particles comprising shells of polystyrene and cores of a polymercaptan-dimethylaniline mixture with silver nanowires dispersed therein are prepared; the core-shell structure nano-particles are dispersed in an isotropic conducting resin filled with silver nanowires; under the action of an external force, the core-shell structure nano-particles fracture automatically; the polymercaptan-dimethylaniline mixture and an excess amount of epoxy groups in the isotropic conducting resin undergo a rapid reaction so that resin microcracks produced by the external force are repaired automatically; and simultaneously, the silver nanowires of the core-shell structure nano-particles are uniformly dispersed on repaired places so that repairing effects on a conductive network are obtained. Therefore, a service life of a conducting resin is improved and a cost of an electron component is reduced.

The invention discloses a metabonomics-based diagnosis marker for chronic obstructive pulmonary disease and application thereof. The diagnosis marker comprises the following 28 blood plasma metabolismmarkers: phosphatidylcholine PC 16:1-36:3, phosphatidylcholine PC 26:0-22:4, phosphatidylcholine PC 26:0-22:3, phosphatidylcholine PC 47:5e, phosphatidylcholine PC 44:11e, phosphatidylcholine PC 16:0-24:5, phosphatidylcholine PC 20:2-20:3, phosphatidylcholine PC 40:10, phosphatidylcholine PC 38:9e, phosphatidylcholine PC 18:1-20:4, phosphatidylcholine PC 16:0-20:3, phenylacetaldehyde, dihydrouracil, nicotinamide, 4-methoxycinnamic acid, ketovaline, threonine, DL-3-aminoisobutyric acid, pyruvic acid, stachyose, caffeic acid, N, N-dimethylaniline, maltotriose, D(-)-gulonate-gamma-lactone, and L-asparaginase. The marker provided by the invention has good classification on metabolome data of patients suffering chronic obstructive pulmonary disease and healthy people, and can accurately distinguish the patients suffering chronic obstructive pulmonary disease from the healthy people.

The invention discloses a synthesizing method of adenine represented by a formula (I). The method comprises steps that: (1) acetyl hypoxanthine represented by a formula (III) and excess phosphorus oxychloride are subject to a chlorination reaction under the catalyzing of N,N-dimethyl aniline; the reaction is sufficiently carried out, and then 6-chloropurine represented by a formula (II) is obtained after processing; (2) in an autoclave, ammonia gas is delivered to an aqueous solution of 6-chloropurine until saturated; the autoclave is sealed, and a temperature in the autoclave is increased to120 to 140 DEG C; a reaction is processed until the materials are completely reacted; the pH value of the reaction liquid is regulated to 7-8; the reaction liquid is cooled, an adenine crude product is precipitated; the adenine crude product is refined by using water, and is processed through active carbon decoloration, such that adenine represented by the formula (I) is obtained. The synthesizing method provided by the invention is advantaged in high production efficiency, high reaction yield, good product quality, low three-waste rate, and low production cost.

The invention relates to a fold-resistant white plastic film and a preparation method thereof. The fold-resistant white plastic film is prepared from the following components in parts by weight: 18 to 25 parts of bisphenol S-type epoxy resin, 5 to 11 parts of cellulose acetate butyrate, 1 to 3 parts of diaminopropyl polydimethylsiloxane, 0.1 to 2 parts of polymethyl hydrogen siloxane, 0.02 to 0.8 parts of boron trifluoride-dimethylaniline, 0.02 to 0.06 parts of isophorone diamine and 55 to 75 parts of aqueous solution of polyethylene glycol. The invention also provides the preparation method of the fold-resistant white plastic film.

A process for preparing high-purity pentazolol features the reaction between 1-(4-chlorphenylethyl)-1-tert-butyl-1, 2-epoxy ethane and 1,2,4-triazole in organic polar solvent under existence of alkali while adding catalyst chosen from N,N-dimethyl-4-aminopyridine, N,N-dimethylphenylamine, methylphrrolidone, dimethyl formamide, methanol sodium, ethanol sodium, potassium hydroxide and sodium hydroxide. Its advantages are high output rate and high purity.

The invention relates the electrostatic resistance resin anchoring agent, comprising clay and curing agent. The clay comprises unsaturated polyester resin, dimethylaniline, white carbon black, silica powder, and acetylene black. The curing agent comprises water, silica powder, benzoyl peroxide, sodium carboxymethylcellulose and acetylene black,. The invention adds acetylene black in clay and curing agent, so the invention has good antistatic property. The invention can meet the request for static electricity at many producing stations. The invention has the advantages of simple technology and easy operation.

The invention relates to a preparation method of sulfadoxine, which comprises the following steps: (1) reacting methyl methoxyacetate and excessive diethyl oxalate to generate 3-methoxy-2-oxo-methylethyl succinate, and decarbonylating to obtain 2-methoxy-methylethyl malonate; (2) reacting the 2-methoxy-methylethyl malonate and formamide to generate a cyclocompound; (3) carrying out chlorination reaction; (4) carrying out condensation reaction; and (5) carrying out methoxylation reaction. The purity of the 2-methoxy-methylethyl malonate obtained in the step (1) is strictly controlled, and the cyclocompound in the step (2) is controlled to exist in the form of anhydrous hydroxy sodium salt; in the step (3), no catalyst, including N,N-dimethylaniline, is used; and in the step (5), solid sodium hydroxide is substituted for sodium methoxide solution. The invention is easy to operate, has the advantage of high product quality, greatly lowers the production cost, and has obvious economic benefit and environmental benefit.

The invention relates to a one-pot method for preparing ropivacaine. According to the invention, L-piperidine-2-carbonyl chloride is prepared from L-piperidine-2-carboxylic acid; intermediate separation is not needed, and the material is directly subjected to a reaction with 2,6-dimethylaniline, and (S)-N-(2,6-dimethylphenyl)piperidine-2-carboxamide is prepared; intermediate separation is not needed, and the material is directly subjected to a reaction with bromopropane, such that ropivacaine is prepared. According to the invention, when the intermediate is prepared, no separation is needed, and reactions can be directly carried out. The method is green and environment-friendly. With the method, process operation is simplified, cost is reduced, and yield is improved. The method is more suitable for large-scale industrialized productions.

The invention relates the flame-retarded resin anchoring agent, comprising clay and curing agent. The clay comprises unsaturated polyester resin, dimethylaniline, white carbon black, silica powder, diphenyl ether, and antimony trioxide. The curing agent comprises water, silica powder, benzoyl peroxide, sodium carboxymethylcellulose and antimony trioxide. The invention adds fire retarding agent in clay and curing agent, so the invention has good fire-retardancy. The invention has the advantages of simple technology, and easy application.

The invention discloses a synthesis method of mefenamic acid. The method comprises the following steps: firstly adding o-halophenylacetic acid, 2,3-dimethylaniline, acid binding agent, catalyst and water in a reaction container to react; then adding water in the reaction mixture to dilute, then acidifying to ensure that the pH value is 2-3, cooling to the room temperature, filtrating, washing filter residue with warm water to obtain raw mefenamic acid; then adding the raw mefenamic acid in a reaction container, then adding organic solvent to perform recrystallization, filtrating to obtain solid, dissolving the obtained solid in organic solvent to perform second recrystallization, filtrating, and drying to obtain the target product. The synthesis method of mefenamic acid in the invention has the advantage that the production cost is low, the utilization of reaction raw materials is complete, the product purity is high, the environmental pollution is little, the operation safety is high, and the method is environmentally friendly and is applicable to industrial production.

The invention provides a method for preparing lidocaine. The method comprises the following steps: using 2,6-dimethylaniline and chloroacetic chloride as raw materials to prepare an intermediate, namely acetyl chloride-2,6-dimethylaniline, and using the prepared intermediate and diethylamine to react and obtain lidocaine, wherein acetone is used as solvent and carbonate is used as catalyst in thereaction process. The method of the invention has simple synthetic technology and does not require the complicated step that the intermediate is washed with acid firstly and washed with base secondlyin the post-treatment, thus avoiding unnecessary loss. Therefore, the yields of the intermediate and lidocaine prepared by the method are higher; and the prepared lidocaine has high purity which is more than 99%, and good industrial application prospect. In addition, the method of the invention uses acetone as solvent, thus the solvent is non-toxic basically and environmentally friendly, has no stimulation and can be recycled.

The invention relates to a cracking process of organosilicon high-boiling components.. The cracking process is characterized in that organosilicon high-boiling components are used as raw materials and are subjected to impurity removal, N,N-dimethylaniline, N,N-diethylformamide or tri-n-butylamine are selected as a catalyst, the catalytic cracking is performed inside a reaction vessel to which hydrogen chloride gas is introduced, and finally, dimethyldichlorosilane, monomethyltrichlorosilane, monomethyldichlorosilane and trimethylchlorosilane are respectively recovered through a layered cooling tower at different temperatures. The cracking process has the advantages that the matching is reasonable, the operation is simple, the recovery ratio is high, and more than 60% of dimethyldichlorosilane product with high added value can be obtained.

The invention provides a method for preparing lidocaine hydrochloride, and belongs to the technical field of anesthetic synthesis. The method comprises the following steps: by taking 2,6-xylenol as a raw material, Pd / C as a main catalyst and 2,6-dimethylcyclohexanone as a promoter, performing liquid phase amination with ammonia water at high temperature, thereby obtaining a midbody 2,6-dimethylaniline; enabling sodium methylate, 2,6-dimethylaniline and N,N-lignocaine methyl acetate as raw materials to react at 90-95 DEGC, distilling while reaction is performed to remove methanol till no methanol can be evaporated out, continuously reacting for 30 minutes, cooling to the room temperature, adding dichloroethane, washing with water, and leaving to stand to layer, thereby obtaining an organic layer, namely, a lidocaine based dichloroethane solution; further adding hydrochloric acid into the lidocaine based dichloroethane solution, adjusting the pH value to be 3.5-4 by using hydrogen chloride, adding activated carbon to reflux for 20-40 minutes, filtering, concentrating the filtrate, cooling, crystallizing, and dying, thereby obtaining lidocaine hydrochloride. The lidocaine hydrochloride prepared by using the method is simple in synthesis process and high in product purity, that is, the purity can be greater than 99%, and the total yield is greater than 84%.

The invention relates to an improvement of the producing method of methylchlorosilane, adding methylchlorodisilane, and a catalyst N, N-dimethylaniline1 accounting for 1-2% of the weight of methylchlorodisilane into a cracking kettle, making the materials a certain quantity, where the kettle is installed with a fractionating tower. It controls temperature at 90-110 deg.C, charging hydrogen chloride into the materials, making the molar ratio of methylchlorodisilane to hydrogen chloride 1 to 0.9-5.5, and its characteristic: the ratio of the height of the crackling kettle to the diameter = 1.0-2.0; the flux of the hydrogen chloride is 16 cu m / h; reacting for 5 hours, and then supplementing methylchlorodisilane into the kettle, and later supplementing once at 2h intervals, supplementing the hydrogen chloride once 200 kg, and completing in 0.5 h; supplementing the catalyst 2 kg at 4h intervals and completing in 10 minutes. It continuously reacts for 28-36 h, and collects condensate. It does not preprocess raw materials, and the sum of methylhydrodichlorosilane and dimethyldichlorosilane higher than that of existing techniques.

The invention discloses a waterproof and anticorrosive paint special for marine ships. The paint comprises 60-85wt% of a component A and 15-40wt% of a component B. The component A comprises the following raw materials: epoxy resin, chlorinated rubber, an ethylene chloride-vinyl acetate copolymer, organic fluorine modified acrylic resin, a silane coupling agent, zinc powder, mica powder, iron oxide red, ceramic micro-powder, molybdenum disulfide, propylene glycol butyl ether, propylene glycol methyl ether acetate, a dispersing agent, an organic silicon defoamer, a leveling agent, methyl isobutyl ketone and n-butanol; and the component B includes the following raw materials: poly 2, 3-dimethylaniline modified montmorillonite, a curing agent, ethyl acetate, and butyl acetate. The waterproof and anticorrosive paint special for marine ships provided by the invention has excellent waterproof performance and corrosion resistance, also has excellent impact resistance, abrasion resistance and weather resistance, has good comprehensive performance when used in ship engineering, and has long service life.

The invention relates to a polyalkyl-substituted aromatic diamine monomer, and the general formula of the structural formula is shown in the figure, wherein R is -CH(CH3)2 or -C(CH3)3; and the preparation is as follows: under nitrogen protection, 2,6-methyl toluidine is heated to the temperature of 100 to 120 DEG C, and the mixed liquid of aromatic formaldehyde and hydrochloric acid is slowly dropped in the 2,6-methyl toluidine and then the mixture is heated for carrying out reflux; after being cooled, 10% aqueous sodium hydroxide solution is dropped into the mixture till the pH value thereof is neutral, and then alcohol is added, the obtain sediment is washed with methanol; after drying of the mixture, chromatographic separation and purification is carried out on the mixture by silicagel column, thus obtaining the polyalkyl-substituted aromatic diamine monomer; the application can be used to prepare soluble, high-temperature resistant polyimide film material with high transparency and low dielectric constant. The substituted aromatic diamine monomer containing polyalkyl prepared in the invention has high purity and is table at room temperature; the preparation method has simple operation and low cost without any special requirement for equipment, thereby being applied to industrial production.

The invention belongs to the field of construction materials and relates to a textured paint. The textured paint consists of the following raw materials in parts by weight: 10-15 parts of water, 40-50 parts of composite emulsion, 15-20 parts of quartz sand, 8-13 parts of silicon-based active gel, 6-9 parts of putty, 12-18 parts of cellulose ether, 2-4 parts of a mildewproof preservative, 1-3 parts of organic zirconium complex, 3-5 parts of dimethyl aniline and 4-7 parts of pentaerythrite, wherein the composite emulsion contains 10-20 percent of polyurethane resin, 30-50 percent of polyacrylic ester resin, 10-20 percent of polyvinyl alcohol resin, 15-25 percent of epoxy resin and 5-15 percent of an emulsifier; putty comprises the following materials in parts by weight: 10-15 parts of polymer powder, 30-50 parts of light clay bricks, 10-15 parts of pearlstone, 6-9 parts of alumina cement, 12-18 parts of mullite, 10-15 parts of bentonite, 2-4 parts of boromagnesite, 1-3 parts of starch sugar powder, 3-5 parts of methyl cellulose, 5-8 parts of silica powder, 5-10 parts of fibrilia or viscose, 8-18 parts of soluble glass, 4-6 parts of dispersible emulsion powder and 10-15 parts of composite suspending liquid. The textured paint has the advantages of long opening time, high cohesiveness, good alkali resistance and excellent water conservation performance.

The invention discloses a preparation method of 2-chloro-4-amido-6,7-dimethoxy quinazoline. The preparation method comprises the following steps: 3,4-dimethoxy benzaldehyde is taken as an initial raw material, then the following reactions are sequentially carried out: oxidizing reaction between the 3,4-dimethoxy benzaldehyde and oxydol, nitration reaction between the 3,4-dimethoxy benzaldehyde and nitric acid, reduction reaction of the 3,4-dimethoxy benzaldehyde and hydrogen ion obtained by iron powder and hydrochloric acid, reaction between the 3,4-dimethoxy benzaldehyde and sodium cyanate, chlorination reaction between the 3,4-dimethoxy benzaldehyde and phosphorus oxychloride, ammoniation reaction between the 3,4-dimethoxy benzaldehyde and ammonia liquor, etc., then the 2-chloro-4-amido-6,7-dimethoxy quinazoline is obtained. The synthetic method takes the commercialized 3,4-dimethoxy benzaldehyde as the initial raw material, and potassium permanganate is not used in the oxidizing reaction process, organic solvents (glacial acetic acid, DMF) are not used in the refining process, the noxious solvent N, N-amino dimethylbenzene or the organic solvent N, N-dimethyl formamide with high boiling point is not used in the chlorination process, so the use amounts of the organic solvents and the phosphorus oxychloride are reduced, thus reducing the production cost, simplifying the production process, protecting the health of operators, reducing 'three wastes' pollution, protecting the environment and greatly improving the reaction yield and the production efficiency.

The invention belongs to the technical field of anti-inflammatory drug production, and relates to a method for preparing mefenamic acid. The method comprises: adding o-chlorobenzoic acid and 2,3-dimethylaniline into a system which is formed by a non-protonic polar solvent and a dehydrant, performing condensation reaction in the presence of an acid-binding agent, a catalyst and a phase-transfer catalyst, and obtaining mefenamic sodium; acidifying the mefenamic sodium and obtaining coarse mefenamic acid products; and refining the coarse mefenamic acid products in an organic solvent and water and obtaining finished mefenamic acid products. The method improves the production efficiency of the mefenamic acid and reduces the production cost of the mefenamic acid.

The invention discloses an environment-friendly and anti-cracking paint which comprises the following components in parts by weight: 35-55 parts of linear alkyl aryl sulfonate, 25-35 parts of hydroxy acrylic resin, 15-20 parts of soybean plant short oil type alkyd resin, 10-15 parts of glycerin, 10-15 parts of turpentine, 15-25 parts of limonene, 5-10 parts of dimethylaniline, 0.1-1 part of a defoaming agent, 0.1-1 part of a flatting agent, 0.1-1 part of a wetting agent, 10-15 parts of mica powder, 10-15 parts of a filler and 1-3 parts of a pigment. The environment-friendly and anti-cracking paint can effectively prevent the paint surface of a floor from being cracked and prolong the service life of the floor; furthermore, the environment-friendly and anti-cracking paint is environment-friendly and healthy, so that toxic gases such as formaldehyde dispersed by the floor are greatly reduced, and the safety of a user is ensured.

The invention belongs to the field of building materials and relates to a textured coating. The textured coating is formed by combining the following raw materials in parts by weight: 10-15 parts of water, 40-50 parts of composite latex, 15-20 parts of quartz sand, 8-13 parts of silica-based active gel, 6-9 parts of putty, 12-18 parts of cellulose ether, 2-4 parts of a mould-proof preservative, 1-3 parts of an organic zirconium complex, 3-5 parts of dimethylaniline, 4-7 parts of pentaerythritol and 3-6 parts of lignocellulose aerogel liquid, wherein the composite latex contains 10-20 percent of polyurethane resin, 30-50 percent of polyacrylate resin, 10-20 percent of polyvinyl alcohol resin, 15-25 percent of epoxy resin and 5-15 percent of an emulsifying agent. A preparation method of the lignocellulose aerogel liquid comprises steps of crushing, purifying, freeze-thawing, solidifying and regenerating. The coating is long in opening time, high in caking property, good in alkali resistance and excellent in water retaining property.

The invention discloses a preparation method of noctilucent fibers capable of emitting red light in darkness. The preparation method comprises the following steps: mixing 2-hydroxybenzaldehyde with 3-hydroxyl-N,N-dimethylaniline which can be dissolved in water to obtain a mixture, heating the mixture, mixing the mixture with anhydrous zinc chloride and sulfuric acid to obtain a mixture I, and carrying out the reaction on the mixture I to obtain a light conversion agent; mixing the light conversion agent with SrAl2O4:Eu<2+>, Dy<3+> and a fiber forming polymer base material to obtain a mixture II, smelting the mixture II, and granulating to obtain noctilucent particles for spinning; and drying the noctilucent particles, then smelting the noctilucent particles and spinning to obtain the noctilucent fibers. The red light emitted by the noctilucent fibers prepared by adopting the preparation method can be maintained for more than ten hours, the highest luminance can reach 3.0cd / m<2>, the emitted red light is one of three basic colors, and the noctilucent fibers can be compounded with one or two of blue light noctilucent fibers and green light noctilucent fibers to prepare luminous colorful noctilucent fibers, so that the important significance can be realized.

The invention discloses a production method of mefenamic acid, which comprises the following steps of: (1) adding water and o-chlorobenzoic acid into a reaction kettle, evenly mixing, and dropwise adding a sodium hydroxide solution while stirring, thereby obtaining a mixed solution; (2) adding solid sodium bicarbonate into the mixed solution in the step (1), adding chalcanthite, 2,3-dimethylaniline and cetyl trimethyl ammonium chloride, and carrying out reflux reaction; (3) after the reflux reaction in the step (2) is finished, dropwise adding hydrochloric acid, and filtering to obtain the crude product; (4) washing the crude product in the step (3) with water, filtering, and drying under reduced pressure to obtain the crude product; and (5) adding dimethyl formamide and water to dissolvethe crude product in the step (4), adding activated carbon to carry out reflux decolorization, filtering, cooling to room temperature to crystallize, filtering, recrystallizing, washing with water after the filtration for the last recrystallization, and drying under reduced pressure to obtain the fine mefenamic acid product. The invention can lower the production cost, easily implement industrialproduction, and overcome the defects in the prior art.

A dry-sheet type serum creatinine detection reagent strip and a preparing method thereof are disclosed and belong to the field of in-vitro diagnosis. A creatinine reacting membrane, a filtering membrane and a diffusion layer in the reagent strip are fixed to a plastic plate in an appropriately overlapping manner. The reagent strip is characterized in that the reacting membrane includes a diluting liquid and a reacting reagent, the diluting liquid includes a buffer liquid, a surfactant, a stabilizer, an adhesive, a coenzyme factor and an aseptic, and the reacting reagent includes creatinine amidohydrolase, creatinase, sarcosine oxidase, peroxidase, 4-aminoantipyrine and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3,5-dimethylaniline. The Trinder reagent is utilized as an indicator probe, an analyte finally generates a colored quinone compound through various enzyme functions, and the creatinine content of a sample is indirectly detected through the coloration degree of the quinone compound. According to the reagent strip and the method, a liquid phase reaction is transferred to a solid carrier, objectives of simple operation and rapid and convenient detection of the creatinine content of the sample are achieved, and the reagent strip and the method are high in sensitivity, good in accuracy and convenient in popularization and application.