52648-79-0Relevant articles and documents
A preparation method of Rhizoma Chuanxiong hydrochlorothizide
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Paragraph 0041-0043; 0050-0052; 0059-0061; 0068-0069, (2017/07/04)
The invention discloses a preparation method of ligustrazine, wherein the preparation method comprises the following steps: adding 3-hydroxy-2-butanone and ammonium acetate as main materials into a reaction vessel, then adding anhydrous ethanol, introducing nitrogen, carrying out water bath heating on the reaction vessel, stirring, stropping introduction of the nitrogen, and waiting the temperature to be dropped to room temperature; adding an aromatization catalyst, then stirring, and filtering to obtain a filtrate A; concentrating the filtrate A to obtain a solution B; adding water and an extraction agent into the B solution, extracting, and taking an upper-layer solution to obtain a solution C; carrying out reduced pressure distillation on the solution C to obtain a solution D; adding water into the solution D, and carrying out cooling crystallization to obtain a mixed material E; and filtering the mixed material E to obtain ligustrazine crystals. The reaction time is greatly shortened, the purification processing is more convenient, the method has the advantages of energy conservation and environmental protection, the prepared ligustrazine is in a needle-shaped crystal form, and the yield can reach 87%.
Cytostatic thymine derivatives of 2-imidazolethione
Guglielmi
, p. 1733 - 1738 (2007/10/05)
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