The molecule is a precorrin carboxylic acid anion obtained by deprotonation of the carboxy groups of cobalt-precorrin-5B; major species at pH 7.3. It is a conjugate base of a cobalt-precorrin-5B.
cobalt;3-[(1Z,2S,3S,4Z,7S,11S,14Z,17R,18R)-8,13,17-tris(2-carboxylatoethyl)-2,7,12,18-tetrakis(carboxylatomethyl)-2,7,11,17-tetramethyl-10,18-dihydro-3H-corrin-21,23-diid-3-yl]propanoate