2-Butenedioic acid (2Z)-, monomethyl ester 2-Butenedioic acid (Z)-, monomethyl ester (9CI) 2-Butenedioic acid, monomethyl ester 3052-50-4 EINECS 221-271-3 Hydrogen methyl maleate Maleic acid, monomethyl ester Methyl hydrogen maleate Monomethyl (Z)-2-butenedioate Monomethyl maleate NSC 11205 NSC 525206