preferred_name: 3-{(2Z)-2-{[3-(2-carboxyethyl)-5-{(Z)-[(3E,4S)-3-ethylidene-4-methyl-5-oxopyrrolidin-2-ylidene]methyl}-4-methyl-1H-pyrrol-2-yl]methylene}-4-methyl-5-[(Z)-(3-methyl-5-oxo-4-vinyl-1,5-dihydro-2H-pyrrol-2-ylidene)methyl]-2H-pyrrol-3-yl}propanoic acid