Synthesis And Analysis Of 4-Ethyl-1-Chloroformyl-2,3-Dioxopiperazine

4-ethyl-1-chloroformyl-2,3-dioxopiperazine, the intermediate of preparingoxopiperazinyl penicillin,which is widely applied in the production ofbacteriophage. Oxopiperzinyl penicillin has strong antibacterial effect on the G+and G- bacilli. Additionally, it has not only a benign curative effect for thesymptom arising from Pseudomonas aeruginosa,Proteus,Escherichia coli andSerratia, but has also especial effect for Pseudomonas aeruginosa that hasdrug-resistant for gentamicin and aminobenzyl penicillin,the demand in thedomestic market has been rising all the time.This paper described the process of 4-ethyl-1-chloroformyl-2,3-dioxopiperazine(EOCP) and analyzed and characterized the product.(1) Gas Chromatography and Chemical Analysis were used to measure4-ethyl-1-chloroformyl-2,3-dioxopiperazineSelecting Chromosorb W-Bw+5%KOH+20%Apiezon L(1.8m×4mm)for packer column, flow velocity 15ml/min, column temperature 90℃, hydrogenflame detector using the mixture of hydrogen(40ml/min) and oxygen (600ml/min), detector temperature 170℃, injecting quantity 1μl. Under theestablished chromatography conditions, the measured area of chromatographypeak shows a good linear relationship, its regression equation isy=3703.6x-22057 and its related coefficient is R~2=0.9998; recovery is 98.62%～100.05%, precision is RSD≤0.32%, purity is 99.47%.Argentimetry was used to analyse EOCP, for its simple operation. It'srecovery is 98.08%～100.96%, Average recovery is 99.37%; precision is RSD≤1.02%. It has reaches the requirement of qualitative analysis and can act as thecriterion of quality control analysis of 4-ethyl-1-chloroformyl-2,3-dioxopiperazine.(2) The synthesis of 4-ethyl-1-chloroformyl-2,3-dioxopiperazine4-ethyl-1-chloroformyl-2,3-dioxopiperazine was prepared by adding4-ethyl-2,3-dioxopiperazine into dichloromethane, then introducing triphosgeneunder low temperature, in which trimethylchlorosilane was protective group andtriethylamine was catalyst. After basing on reviewing the reaction conditionson the yield effect that include the following factors: the select of solvent andacyl halide, reaction time, material ratio, reaction temperature and so on, theoptimized reaction conditions were gained; the resulting product yield was94.12%.