- Preparation method of N, N-dimethylacetamide
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The invention provides a preparation method of N, N-dimethylacetamide, which comprises the following steps: 1) enabling pentamidine hydrochloride and dimethyl acetylsuccinate to react under the action of organic amine to obtain 2-(2-n-butyl-4-hydroxy-6-methylpyrimidine-5-yl)-methyl acetate, wherein the pKa of the organic amine is 8-11.5; 2) enabling the 2-(2-n-butyl-4-hydroxy-6-methylpyrimidine-5-yl)-methyl acetate to react with dimethylamine, so as to obtain the 2-(2-n-butyl-4-hydroxy-6-methylpyrimidine-5-yl)-N, N-dimethylacetamide. The preparation method provided by the invention has the advantages of simple reaction and post-treatment process, high atom economy and low cost.
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Paragraph 0051-0052; 0058-0063; 0067-0068; 0097-0098; ...
(2021/09/04)
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- Method for preparing Fimasartan
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The invention discloses a method for preparing Fimasartan. The method comprises the steps that valeronitrile is used as a raw material to prepare pentanimidamide hydrochloride, then pentanimidamide hydrochloride and acetylsuccinic acid diethyl ester conduct a cyclization reaction and an amidation reaction to prepare 2-(2-normal-butyl-4-hydroxyl-6-methylpyrimidine-5-radical)-N,N-dimethylacetamide (intermediate II), the intermediate II is subjected to sulfo-carbonylation through a Lawesson's reagent to obtain 2-(2-normal-butyl-4-hydroxyl-6-methylpyrimidine-5-radical)-N,N-dimethylacetamide (intermediate III), the intermediate III is subjected to an N-alkylation reaction, radicals are protected through detritylation, and Fimasartan is prepared. The preparation method has the advantages of highreaction selectivity, high synthesis yield, high reaction efficiency and the like.
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- Method for synthesizing Fimasartan
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The invention discloses a method for synthesizing Fimasartan. The method comprises the steps: subjecting a compound VI and a compound VII to a reaction in toluene, so as to obtain a compound V; subjecting the compound V and pentamidine hydrochloride to a reaction in the presence of alkali metal hydroxide, so as to obtain a compound IV; subjecting the compound IV to hydrogen drawing with lithium hydride in a mixed solvent prepared from toluene and DMF, and then, carrying out an N-alkylation reaction with 2-cyano-4'-bromo-methyl biphenyl, so as to obtain a compound III; subjecting the compound III and sodium azide to a reaction in DMF in the presence of zinc chloride, so as to obtain a compound II; and subjecting the compound II to a thio amidation reaction with a Lawesson's reagent, therebyobtaining the target product I. According to the method, the process is simple, the operation is simple and convenient, the raw materials are readily available, and the method is economical and efficient, so that the production cost of the Fimasartan is greatly reduced, and the industrial production is easy to achieve.
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Paragraph 0070; 0071; 0072
(2018/05/16)
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- A preparation method of the midbody non-Ma Shatan (by machine translation)
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The invention discloses a method of preparing intermediates of non-Ma Shatan, including: a) 2 - (2 - butyl - 4 - hydroxy - 6 - methyl - pyrimidine - 5 - yl) - acetic acid with a carbonyl di-imidazole in the presence of an alkali reaction; b) step a) the obtained product with dimethylamine reaction, to obtain 2 - (2 - butyl - 4 - hydroxy - 6 - methyl - pyrimidine - 5 - yl) - N, N - dimethyl acetamide. Compared with the prior art, the invention of the intermediate non-Ma Shatan preparation method has the following advantages: (1) inhibiting the generation of by-product urea, the by-product urea in conventional preparation generated in the process and can be easily removed in the purification process. (2) simplified post-processing operation program, the production efficiency is improved, after the reaction product by crystallization, direct filtration to obtain the target compound. (3) the use of the save a large amount of the extraction solvent, the energy consumption is saved, and reduce the production cost. Compared with the conventional preparation method more easy industrialized application. (by machine translation)
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Paragraph 0048; 0049; 0050; 0051; 0052; 0053; 0054-0057
(2017/06/20)
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- NOVEL PREPARATION METHOD OF 2-(2-N-BUTYL-4-HYDROXY-6-METHYL-PYRIMIDIN-5-YL)-N,N-DIMETHYLACETAMIDE
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The present invention provides a method for preparing 2-(2-n-butyl-4-hydroxy-6-methyl-pyrimidin-5-yl)-N,N-dimethylacetamide, comprising reacting a compound of the following formula 2 with pentanamidine or a salt thereof in the presence of a base. [Formula 2] wherein R1 represents C1-C6 linear or branched alkyl or C3-C6 cycloalkyl. Further, the present invention provides a method for preparing 2-(2-n-butyl-4-hydroxy-6-methyl-pyrimidin-5-yl)-N,N-dimethylacetamide, comprising the steps of: a) reacting 2-(2-n-butyl-4-hydroxy-6-methyl-pyrimidin-5-yl)-acetic acid with a haloformate compound in the presence of a base, and b) reacting the product of Step a) with dimethylamine.
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Page/Page column 9
(2011/08/08)
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