The molecule is an alpha-amino acid zwitterion resulting from a transfer of two protons from the carboxy groups to the amino groups of isonocardicin C; major species at pH 7.3. It is a tautomer of an isonocardicin C.
(2S)-2-azaniumyl-4-[4-[(1R)-1-azaniumyl-2-[[(3S)-1-[(R)-carboxylato-(4-hydroxyphenyl)methyl]-2-oxoazetidin-3-yl]amino]-2-oxoethyl]phenoxy]butanoate