The molecule is zwitterionic form of 3-hydroxy-4-methyl-L-kynurenine arising from transfer of a proton from the carboxy to the amino group; major species at pH 7.3 It derives from a 3-hydroxy-L-kynurenine zwitterion and a L-kynurenine zwitterion. It is an enantiomer of a 3-hydroxy-4-methyl-D-kynurenine zwitterion.
(2S)-4-(2-amino-3-hydroxy-4-methylphenyl)-2-azaniumyl-4-oxobutanoate