C3H4CO2H2

Citraconic Cit`ra*con"ic, a. [Citric + aconitic.] Pertaining to, derived from, or having certain characteristics of, citric and aconitic acids. [1913 Webster]

{Citraconic acid} (Chem.), a white, crystalline, deliquescent substance, {C3H4(CO2H)2}, obtained by distillation of citric acid. It is a compound of the ethylene series. [1913 Webster]