| 摘要 |
PURPOSE: A method for preparing a pemetrexed disodium salt is provided to obtain a high purity of pemetrexed diethyl ester and pemetrexed disodium salt with high yield. CONSTITUTION: A method for preparing high purity pemetrexed diethyl ester of chemical formula 1 comprises: a step of dissolving low purity pemetrexed diethyl ester in a mixture solvent; a step of adding one selected from C3-C6 ketone, C3-C6 ester, and acetonitrile and depositing a crystal; and a step of filtering, washing, and drying the crystal. The mixture solvent contains: a solvent selected among dimethylformamide, dimethyl sulfoxide, dimethylacetamide, and N-methylpyrrolidanone; and a co-solvent selected from C1-C4 alcohol.
|
