A high purity 1 - methyl -5 - ethyl -5 - phenyl barbituric acid preparation method
The purpose of this invention is to provide a process for preparing high-purity 1 - methyl - 5 - ethyl - 5 - phenyl barbituric acid (hereinafter mentioned as compound I) preparation method, comprises two steps: A, α - ethyl - α - phenyl malonic acid diethyl (hereinafter mentioned as compound III) in the presence of a methanol solution of sodium methoxide, the role of the methylluracil prepared with 1 - methyl - 5 - ethyl - 5 - phenyl barbiturics acid sodium (hereinafter mentioned as compound II); compound II in hydrochloric acid to acidification to prepare the compounds I to the crude; B, the above obtained compound I for ethanol aqueous solution of the crude product recrystallized to obtain compound I of the exquisite; the process is stable, easy control of reaction conditions, the product quality is stable, the obtained crude product HPLC content of 99.0% or more, by one-time of the product after purifying>HPLC purity 99.9%, high yield, low production cost, is more suitable for industrial production.
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Paragraph 0017-0028
(2019/05/15)
Hydrolysis of N,N- and N,S-dimethyl derivatives of 2-thiophenobarbital
Kinetics of hydrolysis of N,N- and N,S-dimethyl-2-thiophenobarbital and products of this reaction were investigated. The UV spectroscopy served as a tool for kinetic investigations and chromatography was used to separate and isolate the main products of hydrolysis. These products were identified by spectroscopic methods and the course of hydrolysis of both isomers was compared.
Tarsa, Monika,Zuchowski, Grzegorz,Bojarski, Jacek
p. 253 - 256
(2007/10/03)
Methylation of 5-ethyl-5-phenyl-2-thioxo-4,6(1H,3H,5H)-pyrimidinedione
Methylation of the title compound (2-thiophenobarbital) under different conditions yielded two pairs of isomeric N-, and S--monomethyl and N,N'- and N,S-dimethyl derivatives.Spectral data confirm their structure and allow to identify the methyl substitution.Preliminary results of irradiation of N-CH3 substituted compounds are also presented. Key words: pyrimidines, sulfur compounds, 2-thiobarbiturate
Kubaszek, M.,Paluchowska, M.,Chmiel, E.,Bojarski, J.