The molecule is an L-arginine derivative in which the omega-nitrogen atoms carries a hydroxy group and one of the omega-nitrogen atoms carries a methyl group; major species at pH 7.3. It is a L-arginine derivative and a non-proteinogenic L-alpha-amino acid. It derives from a L-argininium(1+).
(2S)-5-[(Z)-[amino(methylamino)methylidene]-hydroxyazaniumyl]-2-azaniumylpentanoate