Edaravone prodrug compound and pharmaceutical use thereof in treatment or alleviation of neurodegenerative or motor neuron disease

A compound represented by the following Chemical formula 1 or a pharmaceutically acceptable salt thereof.

• In Chemical Formula 1,
• R1 and R2 are each independently hydrogen or (C1-C3)alkyl,
• R3 is any one selected from the group consisting of (C1-C3)alkyl, (C3-C7)cycloalkyl, phenyl, —CH2NH2, —CH(CH3)NH2, —CH(CH2OH)NH2, —CH(CH(CH3)OH)NH2, —CH(CH2SH)NH2, —CH(CH(CH3)2)NH2, —CH(C(CH3)3)NH2, —CH(CH2CH(CH3)2)NH2, —CH(CH(CH3)CH2CH3)NH2, —CH(CH2CH2SCH3)NH2, pyrrolidin-2-yl, —CH(CH2Ph)NH2, —CH(CH2PhOH-p)NH2, —CH(1H-indole-3-yl-CH2)NH2, —CH(CH2CO2H)NH2, —CH(CH2CH2CO2H)NH2, —CH(CH2CONH2)NH2, —CH(CH2CH2CONH2)NH2, —CH(1H-imidazol-4-yl-CH2)NH2, —CH2CH2CH2CH2NH2, and —CH2CH2CH2NHC(NH)NH2.