左氧氟沙星脱羧杂质的合成研究

Study on synthesis of levofloxacin decarboxylated impurities

以左氧氟沙星羧酸为原料,先制备左氧氟沙星,再酸性条件下脱羧,经两步合成左氧氟沙星脱羧杂质,其总收率为73%.产物经^(1)H NMR,MS及HPLC确证.HPLC检测结果表明,该杂质纯度超过95%,达到杂质标准品要求.同时对脱羧反应条件、酸浓度、反应时间分别进行优化,脱羧收率可达94%.该工艺原料易得、操作简单,且溶剂可回收,符合绿色化学理念.

Levofloxacin is a widely used antibiotic in clinic.In order to enhance its quality to deal with more and more adverse reactions in clinic,the decarboxylated impurity was synthesized in two steps,using levofloxacin carboxylic acid as starting material.The structure was characterized by ^(1)H NMR,MS and HPLC.The key step of decarboxylation conditions was optimized in reaction conditions,acid concentration,reaction time.Finally,an easy and green rout for synthesizing high purity levofloxacin decarboxylated impurity was obtained.