塞拉菌素合成新工艺研究

Study on New Process for Synthesis of Selamectin

目的改进塞拉菌素的合成工艺。方法以多拉菌素为起始原料,经二氧化锰氧化、一锅法脱糖肟化反应得到关键中间体25-环己烷基-25-去(1-甲丙基)-5-脱氧-5-(肟基)-阿维菌素B1a单糖,用乙腈和水混合溶剂重结晶,再通过氢化反应制得塞拉菌素。结果中间体及目标产物结构均经^(1)H-NMR、^(13)C-NMR和HPLC-HRMS确证,总收率达53.2%,产物纯度97.1%。结论此工艺步骤简化,操作简便,收率高,成本较低,有应用于工业化生产的潜力。

OBJECTIVE To improve the synthetic process of selamectin.METHODS As the starting material,doramectin was firstly oxidated by manganese dioxide and then the key intermediate 25-cyclohexyl-25-de(1-methypropyl)-5-demethoxy-5-hydroxyimino-avermectin Bla monosaccharide was obtained via deglycosidation and oximation.Selamectin was prepared by hydrogenation after recrystallization with acetonitrile and water.RESULTS The structures of intermediates and product were confirmed by ^(1)H-NMR,^(13)C-NMR and HPLC-HRMS,the total yield was 53.2%and the purity of the product was 97.1%.CONCLUSION This synthetic process is charactered by simplified step,simple operation,high yield and lower cost,which exhibits the potential to be applied for industrial production.