47 results about "Phenylcarbamates" patented technology

The invention discloses a method for determining an impurity F in captopril tablets through high performance liquid chromatography and belongs to the technical field of pharmaceutical analysis. Detection is performed under the conditions as follows: an amylase-tris(5-chloro-2-methyl phenyl carbamate) coated chromatographic column is used, normal hexane-absolute ethyl alcohol-trifluoroacetic acid serves as a mobile phase, a volume ratio of the normal hexane to absolute ethyl alcohol to trifluoroacetic acid is 80:20:0.1, a detection wavelength is 215nm, flow velocity is 1ml/min, a column temperature is 35 DEG C and a sample amount is 20[mu]l. A structural formula of the impurity F is as shown in the description. According to the method disclosed by the invention, the content of the impurityF in the captopril tablets can be quantitatively determined, so that the quality of the captopril tablets is effectively controlled. According to the method provided by the invention, the captopril and the impurity F can be proved to be effectively separated in a system suitability solution, and the method has high precision and high separation degree. A signal to noise ratio of a self-contrast solution is more than 10, and if the sample contains the impurity F, the impurity F can be detected.

The invention discloses a preparation method for 4-(4'-aminophenylmethylene) methyl N-phenylcarbamate. Methyl carbonate, diaminodiphenylmet hanes, solvent and catalyst are added into a reactor, the air in the reactor is replaced by aerating nitrogen, the self-pressure lifting is made at the reaction temperature between 150 and 180 DEG C, the reaction is made for 0.5 to 4 hours under the stirring, the mixture obtained after the reaction is filtered, then crystallization solvent is used to make two to three recrystallizations to the filter cake, white crystalloid solids precipitated at 30 DEG C are taken, and the solids are the target product. The method has the advantages of low cost, no pollution and simple preparation.

(S)-N-ethyl-N-methyl-3-[1-(dimethylamino)ethyl]-phenyl carbamate (formula (1)) or at least one active ingredient according to formula (2) for the preventive protection of people from poisoning caused by cholinesterase inhibitors.

The invention discloses a method for splitting a chlortrimeton enantiomer by using simulated moving bed chromatography. The method is characterized by comprising the following steps: by adopting a simulated moving bed chromatography system, taking silica gel of amylose-tri(3,5-dimethyl phenylcarbamate) as a filler, and taking a mixed solution of normal hexane and isopropyl alcohol as a mobile phase, splitting the chlortrimeton enantiomer under normal phase conditions, thereby obtaining high-purity R-chlortrimeton and S-chlortrimeton. The simulated moving bed chromatography system has the advantages of continuous production, high degree of automation and high production efficiency.

A process for the preparation of compound of formula (I); wherein R¹ is hydrogen, linear, branched or cyclic lower alkyl, cyclohexyl, allyl, propargyl or benzyl; R² is hydrogen, methyl, ethyl or propyl; or R¹ and R² together with the nitrogen to which they are attached form a cyclic moiety of three to eight-membered ring, with or without a hetero atom like nitrogen or oxygen; R³ is hydrogen or lower alkyl; R⁴ and R⁵ are the same or different and each is a lower alkyl; comprising reacting compound of formula (II); wherein R³, R⁴ and R⁵ are as defined above, with compound of formula (III); wherein R¹ and R² are as defined above, in the presence of a base, and further resolving the compound of formula (I) to obtain (S)-isomer of compound of formula (I), substantially free of R-isomer.

The invention provides a method for detecting beta-elemene and related substances thereof, which comprises the following steps of: performing isocratic elution by taking a polysaccharide derivative ofwhich the surface material is amylose-tris (3-chloro-5-methylphenyl carbamate) as a filler and acetonitrile water as a mobile phase. According to the method, beta-elemene can be effectively separatedfrom adjacent impurities and all the impurities, the reproducibility is good, beta-elemene and related substances thereof can be accurately detected, the problem that beta-elemene and related substances thereof are difficult to separate is effectively solved, and therefore it is guaranteed that the quality of beta elemene is controllable.

An O-GlcNAcase-specific inhibitor and substrate are engineered by the extension of the N-Acetyl Moiety of O-(2-acet-amido-2-deoxy-D-glucopyranosylidene)amino-N-phenylcarbamate (PUGNAc). The reagent substrate includes a fluorophor and the inhibitor. This reagent substrate is for high-throughput analysis of O-GlcNAcase within cellular assays and imaging agent for the in vivo analysis of O-GlcNAcase.

The present invention discloses a 3-cyanopyridine production method, which belongs to the technical field of fine chemical production, raw material molar ratio is as follows: 3-methylpyridine:ammonia:oxygen:homemade catalyst is 1: 4-14: 12-40: 1.5-2.5; and key points of the production method are as follows: 1, selection of the raw material ratio; 2, selection of appropriate temperature, to be more specific, the temperature is as low as possible under possible conditions;3, selection of reaction time; and 4, selection of a catalyst, to be more specific, the catalyst is selected for more full reaction to obtain a highest yield. The 3-cyanopyridine production method has the advantages of simple production process, low production cost and no pollution, the product yield can reach 70%, the content can reach 90%; the main use of the product is as follows: 1. 3-cyanopyridine is used as a dye intermediate; 2. the 3-cyanopyridine is used as a pesticide pymetrozine intermediate, rodenticide pyridyl phenylcarbamates and mieshujing intermediate; 3. and the 3-cyanopyridine is used as a pharmaceutical intermediate, pigment intermediate, resin intermediate, and the like, and also used as an important chemical intermediate.

The invention relates to a method of measuring content of optical isomers in (R)-lipoic acid. In the method, a silica gel chiral column coated by amylose-tri-((S)-alpha-methyl-phenylcarbamate) is used, a mixed solvent of an alkane solvent, an alcohol solvent and an organic acid modifier is used as a mobile phase, optical isomers are separated under control of the flow rate and the column temperature of the silica gel chiral column and are detected through an ultraviolet detector, wherein the wavelength of the ultraviolet detector is controlled, so as to obtain the content of the optical isomers of R-lipoic acid. Through adoption of the method, two optical isomers of (R)-lipoic acid can be separated, and the content of each optical isomer of (R)-lipoic acid can be measured accurately, so that the content of optical isomers in R-(+)-lipoic acid tromethamine salt crude drug and preparation can be measured, a foundation is laid for quality analysis and quality control of the R-(+)-lipoic acid tromethamine salt crude drug and the preparation thereof, and the medicine security and effectiveness are ensured.

The invention belongs to the technical field of medicine quality determination, and particularly relates to a method for detecting an isomer in a briviact injection by using high performance liquid chromatography. In order to solve the problem that the method for accurately detecting the isomer in the briviact injection is lacked in the prior art, the technical scheme of the invention is as follows: (1) taking the briviact injection, and diluting the briviact injection to serve as a test solution; (2) detecting the test solution by adopting a high performance liquid chromatography, and judging whether isomer impurities exist or not according to impurity peaks in a map; the chromatographic conditions of the high performance liquid chromatography are as follows: a mobile phase adopts phosphate buffer solution-acetonitrile, and a chromatographic column adopts amylose-tri (3-chloro-5-methyl phenyl carbamate) bonded silica gel as a filling agent. By adopting the chromatographic conditions, the accurate detection of the isomer in the briviact injection can be realized.

The invention provides a high performance liquid detection method for the content of gingerol components. According to the technical scheme, firstly, response characteristics of gingerol components in HPLC detection are analyzed, and a specific detection method is designed on the basis. Specifically, the method comprises the following steps: respectively preparing a to-be-detected sample and a reference substance solution by using a methanol solution, carrying out column chromatography by using amylose-tri (3-chloro-5-methyl phenyl carbamate) as a filler on the basis, and adopting an ethanol-phosphate solution and acetonitrile as mobile phases under the conditions that the column temperature is 34-38 DEG C, the detection wavelength is 330-350 nm, the flow rate is 0.3-0.6 mL/min and the sample size is 30 [mu] L; linear gradient elution is adopted, and the content is calculated according to the peak area by adopting an internal standard method after detection. The method is simple and convenient to operate, the detection efficiency is remarkably improved, the process is easy to standardize, the response is sensitive, the accuracy is high, and the method has a good popularization prospect and outstanding technical advantages.