- Preparation method of anticoccidial drug Diclazuril
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The invention discloses a preparation method of an anticoccidial drug Diclazuril. The method takes 3,4,5-trichloronitrobenzene as a raw material and the 3,4,5-trichloronitrobenzene and 4-chlorobenzylcyanide are subjected to condensation reaction to generate 2,6-dichloro-alpha-(4-chlorobenzyl)-4-nitrophenylacetonitrile; enabling a condensate and hydrazine hydrate to be subjected to reduction to generate 2,6-dichloro-alpha-(4-chlorobenzyl)-4-aminophenylacetonitrile, enabling a reduzate and malonyl ethyl dicarbamate to be subjected to diazo, coupling, cyclization, hydrolysis and decarboxylationone-pot reaction to generate the Diclazuril. The method disclosed by the invention has a simple technology and is easy to operate; the environment protection problem caused by the fact that the odor of thioglycolic acid is great in a decarboxylation process of the Diclazuril is solved; meanwhile, the yield is improved and the total yield of the Diclazuril synthesized by taking 2,6-dichloro p-nitroaniline as the raw material is 43.8 percent, so that the preparation method is suitable for industrial production.
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Paragraph 0027; 0028; 0034; 0035; 0041; 0042; 0058; 0059
(2018/04/03)
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- A coccidian preparation method
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The invention relates to a preparation method for diclazuril. A document reports that the synthesis of diclazuril is carried out in a such way that 2,6-dichloro-para-nitroaniline or 3,4,5-trichloronitrobenzene is used as an initial raw material and is subjected to diazotization reaction, substitution reaction, reduction reaction and the like to prepare a common intermediate 3. The existing process has many steps and is low in overall yield so that the costs of diclazuril raw materials and preparation stay at a high level. The invention provides a synthetic process of diclazuril. Particularly, the synthetic process comprises the steps that an intermediate 4 is prepared by performing reaction on the intermediate 3 and sodium nitrite by means of reduction and is subjected to cyclization and ring enlargement to obtain a product. In the route, a column chromatography means is not adopted; therefore, the process is short in the reaction steps and is suitable for industrial production.
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Paragraph 0031; 0050-0051
(2018/09/02)
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- Diclazuril and isotope internal standard D4-Diclazuril method for the preparation of
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The invention relates to a preparation method for diclazuril and isotope interior label D4-diclazuril. In the invention, 2, 6-dichloro-4-nitroaniline is adopted as a raw material, and the raw material is subjected to a sandmeyer reaction, affinity substitution, reduction, diazotization, diazonium reduction, a two-step condensation reaction, cyclization and refining, so that the diclazuril or the isotope interior label D4-diclazuril competitive product is obtained. According to the invention, during the process, the affinity substitution and the nitro-reduction can be continuously implemented without processing, and the diazotization, the diazonium reduction as well as the two-step condensation reaction can realize one-pot synthesis, the material prepared is high in purity and can reach 99.5%, the total yield is increased by about 10% as compared with that of the prior art, and the blank of the detection field of the medicine is filled up.
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