Abstract:
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 1H-NMR, 13C-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.