gadolinium(III) ion 2-[6,9-bis({1-carboxylato-3-[(2,3-dihydroxypropyl)carbamoyl]propyl})-3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(14),11(15),12-trien-3-yl]-4-[(2,3-dihydroxypropyl)carbamoyl]butanoate [ 933983-75-6 ]