- A high-purity medicinal gemmezine production process
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The present invention discloses a high purity medicinal gemmezine production process. The present invention takes malonitrile and trimethyl orthoxyacetate as the starting material, by condensation reaction, cyclization reaction, chlorination reaction and hydrolysis reaction to obtain gemmepyrimidine, wherein the present invention does not distill sulfonyl chloride and acetic acid in the chlorination step, cooling crystallization after the addition of methanol pulp refining; hydrolysis step using sulfuric acid to remove methyl and cyanogen without concentration directly adjust pH precipitation, and then using absolute ethanol refining, after the use of the above process, reduce the corrosion of equipment and pipelines, and 4-Me-CDHP, N-Me-CDHP, CN-CDEP and other unknown monozythic content is controlled at ≤0.03%, which is more suitable for the needs of industrial production of high-purity meperidine.
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Paragraph 0016; 0036-0037; 0041-0042
(2022/01/10)
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- Preparation method of gimeracil intermediate
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The invention belongs to the technical field of chemical synthesis, and provides a method for preparing a gimeracil intermediate 5-chloro-3-cyano-4-methoxy-2(1H)-pyridone, wherein the method comprisesthe steps: by using 1,1-dicyano-2-methoxy-4-(N,N-dimethylamino)-1,3-butadiene as a starting material, carrying out reflux cyclization in an acetic acid aqueous solution with the mass fraction of 80%,cooling the reaction solution, adding acetic anhydride, heating to a required temperature, dropwise adding sulfonyl chloride for chlorination, and treating to obtain a product. The method is good inyield, high in purity, easy to operate, capable of saving production cost and suitable for industrial production.
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Paragraph 0042-0057
(2020/12/31)
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- A lucky US pyrimidine synthesis method (by machine translation)
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The invention belongs to the technical field of chemical synthesis, in particular to a lucky US pyrimidine synthesis method. The method will be the 3 - cyano - 4 - methoxy - 2 - H - pyridone with sulfonic acid chloride in glacial acetic acid in the separated after the reaction to the 3 - cyano - 4 - methoxy - 5 - chloro 2 - (1H) pyridone; the 3 - cyano - 4 - methoxy - 5 - chloro 2 - (1H) pyridone with hydrobromic acid to obtain lucky US pyrimidine. The invention provides a method for the preparation of pyrimidine lucky US, simple operation, cycle is short, low cost, good product purity, easy product of large-scale production. (by machine translation)
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Paragraph 0022; 0023; 0025; 0027; 0028
(2017/07/01)
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- 5-chloro-3-cyano-4-methoxy -2 (1 H) pyridone synthetic method
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The invention belongs to the technical field of chemical synthesis, and particularly relates to a synthesis method of 5-chloro-3-cyano-4-methony-2-(1H)-pyridinone. The synthesis method comprises the following steps: thionyl chloride is slowly dropped in 3-cyano-4-methony-2-(1H)-pyridinone at the temperature ranging from 0 DEG C to 5 DEG C, the additive amount of thionyl chloride is 5 ml per gram of the 3-cyano-4-methony-2-(1H)-pyridinone, the dropping speed is 1.2-2.0 ml/min, then the temperature is slowly increased until backflow is generated, the heat preservation reaction is performed for 5.5-6.5 hours, thionyl chloride is subjected to pressure reduction and evaporation drying, normal hexane is added, the solids are subjected to pulping for 1 hour, the additive amount of normal hexane is 5 ml per gram of 3-cyano-4-methony-2-(1H)-pyridinone, and filtering and drying are performed, so that 5-chloro-3-cyano-4-methony-2-(1H)-pyridinone is obtained. The synthesis method has the advantages of thorough raw material reaction, high product purity and easiness in purification.
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Paragraph 0013-0017
(2017/06/20)
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- CONVENIENT AND PRACTICAL SYNTHESIS OF 5-CHLORO-4-HYDROXY-2(1H)-PYRIDINONE
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5-Chloro-4-hydroxy-2(1H)-pyridinone (1) was prepared by 4-step reactions via the key intermediate 5-chloro-3-cyano-4-methoxy-2(1H)-pyridinone (5).This synthetic route has several advantages over the reported methods in procedure, yield and applicability.
- Yano, Shin-go,Ohno, Tomoyasu,Ogawa, Kazuo
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p. 145 - 148
(2007/10/02)
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