Provided herein is an impurity of laquinimod, N-ethyl-N-phenyl-1,2-dihydro-4-hydroxy-1-methyl-2-oxoquinoline-3-carboxamide (deschloro laquinimod impurity), and process for preparation and isolation thereof. Provided further herein is a highly pure laquinimod or a pharmaceutically acceptable salt thereof substantially free of deschloro laquinimod impurity, processes for the preparation thereof, and pharmaceutical compositions comprising highly pure laquinimod or a pharmaceutically acceptable salt thereof substantially free of deschloro laquinimod impurity.
本文提供了拉奎尼莫德的杂质,即N-乙基-N-苯基-1,2-二氢-
4-羟基-1-甲基-2-氧基
喹啉-3-甲酰胺(去
氯拉奎尼莫德杂质)的过程及其制备和分离。此外,本文还提供了高纯度的拉奎尼莫德或其药用可接受盐,基本上不含去
氯拉奎尼莫德杂质,以及其制备过程和包含高纯度的拉奎尼莫德或其药用可接受盐的药物组合物。