| 摘要 |
A method relates to obtaining of 5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]thio]-1H-benzimidazole (pirmethazole), comprising the following reaction stages, which are carried out in series in one main solution system, which comprises an organic solvent which is not mixed with water, and added determined water amount within the limits from 0,3 to 5,5mg of water/ml organic solvent, which is not mixed with water, without isolation of intermediate compounds: stage 1) the reaction of (4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl alcohol (pirmethyl ) with chloro-dehydroxylation reagent with obtaining of (4-methoxy-3,5-dimethyl-2-pyridinyl)methyl chloride (pirmethyl chloride); stage 2) the reaction of (4-methoxy-3,5-dimethyl-2-pyridinyl) methyl chloride, obtained at the stage 1 from 2-mercapto-5-mercaptobenzimidazole (metmerkazole) in the presence of a base with formation of 5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]thio]-1H-benzimidazole (pirmethazole).
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