deuterated n-ethyl-n-phenyl-1,2-dihydro-4-hydroxy-5-chloro-1-methyl-2-oxoquinoline-3-carboxamide, their salts and their uses. The present invention provides deuterated n-ethyl-n-phenyl-1,2-dihydro-4-hydroxy-5-chloro-1-methyl-2-oxoquinoline-3-carboxamide, its salts and their uses.deuterado n-etil-n-fenil-1,2-di-hidro-4-hidroxi-5-cloro-1-metil-2-oxoquinolino-3-carboxamida, os seus sais e suas utilizações. a presente invenção proporciona deuterado n-etil-n-fenil-1, 2-di-hidro-4-hidroxi-5-cloro-1-metil-2-oxoquinolino-3-carboxamida, seus sais e seus usos.