稳定同位素氘标记左氧氟沙星-D_(3)的合成

Synthesis of Stable Isotope Deuterium Labeled Levofloxacin-D_(3)

为了提高稳定同位素利用率,建立简便、成本低廉的合成方法,本研究以哌嗪为起始原料,和氯甲酸苄酯(CBZ-Cl)反应得到CBZ-哌嗪,然后与碘甲烷-D_(3)反应得到CBZ-哌嗪-CD_(3),之后脱去CBZ保护得到甲基哌嗪-D_(3),最后和左氧氟沙星羧酸反应得到左氧氟沙星-D_(3)。以投入的碘甲烷-D_(3)物质的量计算,左氧氟沙星-D_(3)产率为37.0%。所合成的左氧氟沙星-D_(3)产品经核磁共振波谱、高效液相色谱和质谱等表征确认,化学纯度为98.5%,同位素丰度为99.5atom%D,以上结果表明,合成的左氧氟沙星-D_(3)可作为同位素内标用于动物源食品中左氧氟沙星残留的定量检测。

In order to improve the stable isotope utilization rate,a simple and inexpensive synthesis method was developed.The synthesis of levofloxacin is based on piperazine as the starting material,and the reaction with carbobenzoxy chloride(CBZ-Cl)to get CBZ-piperazine-CD_(3),and then the reaction with iodomethane-D_(3)to get CBZ-piperazine-CD_(3),after the removal of CBZ protection to get methylpiperazine-D_(3),and finally the reaction with levofloxacin carboxylic acid to get levofloxin-D_(3).The yield of levofloxacin-D_(3)was 37.0%based on the amount of iodomethane-D_(3).The synthesized Levofloxacin-D_(3)product was characterized by nuclear magnetic resonance spectroscopy,high performance liquid chromatography and mass spectrometry.The chemical purity was 98.5%and the isotope abundance was 99.5atom%D.It can be used as the internal standard for the quantitative determination of levofloxacin residue in animal food.