79868-75-0Relevant articles and documents
A D (-)-α - (4-ethyl -2,3-dioxygen piperazin-1-carboxamido) method for the preparation of acetic acid the hydroxybenzotriazole
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Paragraph 0030; 0039; 0040, (2017/01/31)
The invention discloses a method for preparing D(-)-alpha-(4-ethyl-2,3-dioxopiperazine-1-formamido) p-hydoxyphenylacetic acid. 4-ethyl-2,3-dioxopiperazine-1-formate and a salt of D(-)-alpha-p-hydoxyphenylglycine are subjected to a condensation reaction in an aqueous phase to obtain the D(-)-alpha-(4-ethyl-2,3-dioxopiperazine-1-formamido) p-hydoxyphenylacetic acid. The 4-ethyl-2,3-dioxopiperazine-1-formate is used as a raw material, zinc halide is used as a catalyst, and the aqueous phase reaction is adopted, so that the process is compact and environment-friendly, the intermediate EOCP is easy to separate, the use of organic solvents is completely avoided, the working environment is improved, the post treatment cost is saved, the treatment cost of 'three wastes' is greatly reduced, the purity of the obtained HO-EPCP is high, the purity of the one-step crystallized product is more than 96%, re-crystallization is not needed, and the economic and social benefits are significant.
N,N'-carbonyl-bis-(4-ethyl-2,3-dioxo)-piperazine
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, (2008/06/13)
A new compound called N,N'-carbonyl-bis-(4-ethyl-2,3-dioxo)-piperazine of Formula I STR1 A process for the preparation thereof based on the reaction of 4-ethyl-2,3-dioxo-piperazine or a trimethylsilyl derivative thereof with carbonyl chloride or a derivat