The molecule is an octadeca-9,11-dienoate that is the conjugate base of 9-cis,11-trans-octadecadienoic acid, formed by deprotonation of the carboxylic acid functional group. It is a conjugate base of a 9-cis,11-trans-octadecadienoic acid.
(9Z,11E)-octadeca-9,11-dienoate