The molecule is the linear tetrapyrrole anion that is dinoflagellate luciferin protonated to pH 7.3. It is a conjugate base of a dinoflagellate luciferin. It is a conjugate acid of a dinoflagellate luciferin(2-).
(2S,3S,4S,5Z)-4-(2-carboxylatoethyl)-5-[2-[[5-[(3-ethenyl-4-methyl-5-oxo-1,2-dihydropyrrol-2-yl)methyl]-3-ethyl-4-methyl-1H-pyrrol-2-yl]methyl]-3-methyl-4-oxo-1H-cyclopenta[b]pyrrol-6-ylidene]-3-methylpyrrolidin-1-ium-2-carboxylate