58909-39-0Relevant articles and documents
Preparation method of triazine ring
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Paragraph 0017; 0035-0050, (2021/05/08)
The invention belongs to the technical field of preparation of organic intermediates, and particularly relates to a preparation method of a triazine ring. The method comprises the following steps: adding 2-methyl thiosemicarbazide, diethyl oxalate and a mixed alcohol solvent into a reaction flask, dropwise adding a mixed base catalyst, carrying out cyclization reaction at 45-55 DEG C, performing acidifying with hydrochloric acid, performing cooling to 0-5 DEG C, and carrying out suction filtration to obtain a triazine ring crude product; dissolving the triazine ring crude product in distilled water at 65-70 DEG C, performing cooling to 10-15 DEG C, crystallizing to obtain a triazine ring wet product, and drying at 90-100 DEG C for 3-5 hours to obtain a triazine ring dry product. According to the preparation method, a new solvent system is not introduced, the reaction selectivity is high, side reactions are few, the solvent system is easy to recycle, and the product yield is high; the adopted raw materials are cheap, easy to obtain, low in cost and suitable for industrial amplification.
The use of mixed solvent to synthesize triazine ring new method
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Paragraph 0022; 0023; 0024; 0025; 0026; 0027; 0028-0031, (2017/10/07)
The invention relates to a novel method for synthesizing thiotriazinone (TTZ) by using a mixed solvent. The synthetic process comprises the following steps: performing cyclization reaction on 2-methylthiosemicarbazide, the mixed solvent, diethyl oxalate and sodium methylate at 0-45 DEG C to generate triazine ring sodium salt, and acidifying through hydrochloric acid to obtain thiotriazinone. Due to the use of the mixed solvent, the system viscosity of the synthetic process is greatly improved, the TTZ cyclization yield is increased to be more than 90% (by 2-methylthiosemicarbazide), and the content of a byproduct-1-methyl-5-sulfydryl-1,2,4-triazole-3-methyl carboxylate is less than 0.002%, namely less than 20ppm.
Cephalosporin compounds and antibacterial agents
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, (2008/06/13)
Cephalosporin compounds of the formula (I): STR1 wherein R1 and R2 may be the same or different and are a hydrogen atom or a lower alkyl group of 1-5 carbon atoms and A is a hydrogen atom or a nucleophilic compound residue or pharmacologically acceptable salts thereof have excellent antibacterial activity against Gram positive and Gram negative microorganisms.