Patent No. EP3524595 (titled "High-Purity Quinoline Derivative And Method For Manufacturing Same") was filed by Eisai R&D Management on Aug 26, 2015. The application was issued on Aug 10, 2022.
Quinline derivative that is easy to remove such impurities by a common purification method such as chromatography and crystallization. The derivative comprises a compound represented by formula (IV) or a salt thereof; an organometallic reagent such as butyllithium, methyllithium, lithium bistrimethylsilylamide, sodium bistrimethylsilylamide or potassium bistrimethylsilylamide; a hydride such as lithium hydride, sodium hydride or potassium hydride; a heterocyclic compound such as imidazole, pyridine, dimethylpyridine, trimethylpyridine or 4-dimethylaminopyridine; or an organic amine such as triethylamine, N,N-diisopropylethylamine or diazabicycloundecene.

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