The molecule is a metallochlorin that is heme d in which the hydroxy group and the carboxy group of the 6-carboxyethyl substituent have undergone intramolecular condensation to afford the corresponding gamma-spirolactone. It is a ferroheme, a gamma-lactone, an azaspiro compound, an oxaspiro compound, a tertiary alcohol, a monocarboxylic acid and a metallochlorin. It derives from a heme d cis-diol. It is a conjugate acid of a cis-heme d hydroxychlorin gamma-spirolactone(1-).
3-[(2R,17'S)-8',13'-bis(ethenyl)-17'-hydroxy-3',7',12',17'-tetramethyl-5-oxospiro[oxolane-2,18'-porphyrin-21,23-diide]-2'-yl]propanoic acid;iron(2+)