Erik C. Wiener1, Raghvendra Sengar2, Luce Vander Elst3, Marie-Caline Abadjian4, Curtis E. Moore5, Arnold L. Rheingold5, Douglas Grotjahn6
1University of Pittsburgh, Pittsburgh, PA, United States; 2University of Pittsburgh, Johnstown, United States; 3General, Organic and Biomedical Chemistry, University of Mons, Mons, Belgium; 4San Diego State University, United States; 5University of California, San Diego, CA, United States; 6San Diego State University, San Diego, CA, United States
MRI offers the promise of molecular and cellular imaging by using exogenous or endogenous markers. Using exogenous stains requires suitable concentrations at the desired target by delivery of large numbers of paramagnetic or super paramagnetic ions, or a smaller number of more highly efficient agents. This report presents the syntheses of two new bifunctional Gd(III) chelates, with optimal water exchange rates, that can be coupled to other molecules using either click or peptide coupling chemistry. Nuclear magnetic relaxation dispersion experiments demonstrate 100% higher relaxivities then their slower exchange rate controls. Water residence times are measured using 17O NMR.