preferred_name: (Hydrogen 3-((2(sup 2)R,7R,8R,17S,18S)-12-acetyl-7-ethyl-2(sup 2)-(methoxycarbonyl)-3,8,13,17-tetramethyl-2(sup 1)-oxo-2(sup 1),2(sup 2),7,8,17,18-hexahydrocyclopenta(at)porphyrin-18-yl)propanoato-kappa4N(sup 21),N(sup 22),N(sup 23),N(sup 24))palladium