A kind of method for synthesizing clean production of metronidazole crude drug

Abstract

The invention relates to a clean production method for synthesizing metronidazole, and belongs to the field of the organic synthesis of drugs. The method comprises the following steps: 1, utilizing a neutralizing second mother liquor (with the pH value of 10.5-11.0) in a metronidazole synthesis process to substitute a 30% sodium hydroxide solution to be used in a neutralization reaction of a metronidazole hydroxylation liquid; and 2, carrying out concentrated recovery on the above finally obtained metronidazole production mother liquor before emission, neutralizing the mother liquor by sulfuric acid until the pH value is 5.0-6.0, allowing the neutralized solution to stand for above 6h, centrifuging to obtain a nitro substance, and sending the recovered mother liquor to a sewage treatment station. About 200kg of the 30% sodium hydroxide solution is saved each batch, the emission of the neutralizing second mother liquor (with the pH value of 10.5-11.0) is reduced, cycle production is formed, the environmental protection throughput is reduced, and the production cost is reduced. The wet product of the recovered nitro substance in each batch is about 18kg, so the production cost is reduced, and the environmental protection throughout is reduced.

Description

technical field [0001] The invention relates to the production of metronidazole, in particular to a clean production method for synthesizing a metronidazole crude drug. Background technique [0002] Metronidazole, alias: metronidazole. Belongs to national essential medicines. It is white or light yellow crystal or crystalline powder. It has broad-spectrum anti-anaerobic and antiprotozoal effects, and is mainly used to treat systemic or local infections caused by anaerobic bacteria, as well as amoebiasis and trichomonal vaginitis. [0003] At present, there are 7 pharmaceutical factories in my country to synthesize metronidazole raw materials, with a total annual output of about 7,000 tons, 50% of which are sold domestically and 50% are exported. The synthetic process routes are basically the same, and there is a certain degree of environmental pollution, and the pressure on environmental protection is high, and the cost of environmental protection is relatively high. Env...

AI Technical Summary

Problems solved by technology

The synthetic process routes are basically the same, and there is a certain degree of environmental pollution, the pressure on environmental protection is high, and the cost of environmental protection is relatively high.

Environmental pollution is the core problem restricting the production of metronidazole raw materials

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