33 results about "Carbamic acid ethyl ester" patented technology

The present invention relates to the technical field of veterinary medicine, in particular to a method for preparing 2-[phenyl]-1,2,4-triazine-3,5(2H,4H)-diketone compounds, comprising the following steps: (1 ) using dichloroacetyl chloride and ethyl carbamate as reaction raw materials, adding an acid-binding agent and a reaction solvent, heating and undergoing heat preservation reaction, distillation and rectification to obtain (2,2-dichloroacetyl) ethyl carbamate; (2) adding the aniline compound shown in structural formula 2 into hydrochloric acid, after being treated with diazotization reagent, reducing reagent, and acid precipitation reagent, and then washing with neutralization water to obtain the phenylhydrazine compound shown in structural formula 3; (3) Add phenylhydrazine compounds and (2,2-dichloroacetyl) ethyl carbamate into anhydrous acetic acid, add reaction aids, heat until the reaction is complete, and then undergo distillation to obtain 2-[phenyl]-1, 2,4‑triazine‑3,5(2H,4H)‑diones. By using the method, the overall reaction steps are shortened, the economic benefit is improved, and the discharge of three wastes is reduced.

A modified release pharmaceutical formulation includes about 30-70% N-(2-amino-4- (fluorobenzylamino) -phenyl) carbamic acid ethyl ester (retigabine), or a pharmaceutically acceptable salt, solvate or hydrate thereof, about 5-30% of a drug delivery matrix including hydroxypropylmethylcellulose (HPMC), about 1.0-10% of an anionic surfactant, and an enteric polymer. The pharmaceutical formulation produces a sustained plasma concentration of retigabine following administration to a subject for 4-20 hours longer than the time required for in vitro release of 80% of retigabine. A formulation includes about 30-70% N-(2-amino-4- (fluorobenzylamino) -phenyl) carbamic acid ethyl ester (retigabine), or a pharmaceutically acceptable salt, solvate or hydrate thereof, about 5-30% of a drug delivery matrix, and an agent for retarding release in the gastric environment. The plasma concentration vs. time profile of this formulation is substantially flat over an extended period lasting for about 4 hours to about 36 hours. A method of treating a disorder characterized by nervous system hyperexcitability includes administering to a subject an effective amount of these pharmaceutical formulations.

A modified release pharmaceutical formulation includes about 30-70% N-(2-amino-4-(fluorobenzylamino)-phenyl)carbamic acid ethyl ester (retigabine), or a pharmaceutically acceptable salt, solvate or hydrate thereof, about 5-30% of a drug delivery matrix including hydroxypropylmethylcellulose (HPMC), about 1.0-10% of an anionic surfactant, and an enteric polymer. The pharmaceutical formulation produces a sustained plasma concentration of retigabine following administration to a subject for 4-20 hours longer than the time required for in vitro release of 80% of retigabine. A formulation includes about 30-70% N-(2-amino-4-(fluorobenzylamino)-phenyl)carbamic acid ethyl ester (retigabine), or a pharmaceutically acceptable salt, solvate or hydrate thereof, about 5-30% of a drug delivery matrix, and an agent for retarding release in the gastric environment. The plasma concentration vs. time profile of this formulation is substantially flat over an extended period lasting for about 4 hours to about 36 hours. A method of treating a disorder characterized by nervous system hyperexcitability includes administering to a subject an effective amount of these pharmaceutical formulations.

The invention provides a preparation method for a nanofiber membrane used for detecting ethyl carbamate. The preparation method comprises the steps that spinning materials are dissolved in solvent andmixed uniformly to obtain a spinning solution; acetylcholin esterase and a phosphate buffer are mixed to prepare an enzymic preparation; parts of spinning solution and the enzymic preparation are mixed according to the volume ratio that the spinning solution volume to the enzymic preparation volume is (1-2):1, and a spinning solution A is obtained; another parts of spinning solution and a color developing agent are mixed according to the volume ratio that the spinning solution volume to the color developing agent volume is (2-3):1, and a spinning solution B is obtained; the spinning solutionA and the spinning solution B are subjected to electrostatic spinning to obtain the nanofiber membrane. When the nanofiber membrane is utilized to detect ethyl carbamate, the contact area between theethyl carbamate and nanofibers is larger, so that the ethyl carbamate, the color developing agent and the enzymic preparation take effect, thereby generating a color developing result, and the color developing result is utilized to quickly and accurately judge the ethyl carbamate content in a sample.

The invention discloses ethyl carbamate hydrolytic enzyme mutants capable of improving the thermostability, and belongs to the technical field of gene engineering and enzyme engineering. By means of a molecular technical means, the ethyl carbamate hydrolytic enzyme mutants capable of improving the thermostability are obtained, and the half-life periods of the ethyl carbamate hydrolytic enzyme mutants Q328C and Q328V are increased by 7.46 times and 1.96 times respectively compared with a native enzyme. The mutants Q328C, Q328R and Q328 V all have better tolerance at 30 DEG C or above than the native enzyme. In addition, the tolerance to ethyl alcohol and the tolerance to acid of the mutant Q328C are improved.

The structural formula of 1,3-bis(3,4,5-trifluoro-2,6-dinitrophenyl) urea of ​​the present invention comprises the following steps for its preparation method: 3,4,5-trifluoroaniline is substituted The reaction obtains the intermediate product (3,4,5-trifluorophenyl) ethyl carbamate, and then through nitration reaction to obtain 1,3-bis(3,4,5-trifluoro-2,6-dinitrophenyl ) urea. ZXC‑19 has poor solubility in water and is soluble in most organic solvents. It has a very high density at 298K, has good thermal stability, high solid-state heat of formation and good detonation performance, low sensitivity, and no combustion products. Small molecular weight, suitable for use as rocket propellant. 1,3-bis(3,4,5-trifluoro-2,6-dinitrophenyl) urea has a very simple synthesis method, high yield, easy industrial production, environmental friendliness, and easy recrystallization. An important raw material for ZXC‑8.

The invention discloses a production process for improving the yield of hexazinone, comprising the following steps: step S1, first using cyanamide and ethyl chloroformate to generate ethyl cyanocarbamate, and then combining ethyl cyanocarbamate with dimethyl sulfate The ester synthesizes a methyl product under the catalytic condition of a catalyst; step S2, synthesizes a guanidine derivative with a methyl product and dimethylamine; step S3, uses chloroform to perform multiple extractions on the guanidine derivative; step S4, performs precipitation on the guanidine derivative Processing: step S5, reacting guanidine derivatives with cyclohexyl isocyanate to synthesize a hexazinone intermediate under the condition of toluene as a solvent; step S6, performing a cyclization reaction between the hexazinone intermediate and sodium methoxide to prepare hexazinone and washing with water; Step S7, purifying and drying hexazinone to obtain the technical product of hexazinone; the production process of the present invention is easy for industrial production and has strong practicability, and solves the technical problem of low yield of the technical product of hexazinone in the prior art.