Abstract #1899

Relaxometric Properties of Gadolinium Chelates of DOTA-Like Ligands with Axially Uneven Distribution of Donor Atoms

Miloslav Polasek¹, Peter Caravan²

¹Radiology, A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, United States; ²Radiology, Massachusetts General Hospital, Charlestown, MA, United States

We explored a novel design of DOTA-like compounds where removal of an acetate arm on N1 is counterbalanced by a donor arm on N7. Surprisingly, presence of a non-coordinating moiety on N1 lowered kinetic stability of the Gd chelates. Choice of the donor arm on N7 influenced both kinetic stability and water exchange rate, the latter could be tuned over 2 orders of magnitude.