The molecule is a doubly-charged cyclic tetrapyrrole anion obtained by deprotonation of the two pyrrole NH groups of cytoporphyrin. It is a conjugate base of a cytoporphyrin.
(Z)-[3,7-bis(2-carboxyethyl)-12-ethenyl-17-[(4E,8E)-1-hydroxy-5,9,13-trimethyltetradeca-4,8,12-trienyl]-8,13,18-trimethylporphyrin-22-id-2-ylidene]methanolate