The molecule is the cyclic tetrapyrrole anion that is ferroheme o protonated to pH 7.3. It is a conjugate base of a ferroheme o.
3-[18-(2-carboxylatoethyl)-7-ethenyl-12-[(1S,4E,8E)-1-hydroxy-5,9,13-trimethyltetradeca-4,8,12-trienyl]-3,8,13,17-tetramethylporphyrin-21,23-diid-2-yl]propanoate;iron