The molecule is a 2-(omega-methylthio)alkylmaleate(2-) obtained by deprotonation of both carboxy groups of 2-(3-methylthiopropyl)maleic acid; major species at pH 7.3. It is a conjugate base of a 2-(2-methylthiopropyl)maleic acid.
(Z)-2-(3-methylsulfanylpropyl)but-2-enedioate