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