Lanthanide Complexes (Gd^III and Eu^III ) Based on a DOTA-TEMPO Platform for Redox Monitoring via Relaxivity.

ABSTRACT: Three lanthanide complexes (Ln=Gd, Eu) based on a DO3 A ([Ln(L₁ )]) or DO2 A ([Ln(L_2-3 )]⁺ ) platform appended by a redox active TEMPO-based arm were prepared. Complex [Ln(L₂ )]⁺ shows an alkyne arm, offering the possibility of postfunctionalization by click reaction to yield [Ln(L₃ )]⁺ . The complexes demonstrate a redox response whereby the hydroxylamine, nitroxide and oxoammonium forms of the arm can be obtained in turn. Luminescence measurements on the europium complexes support an octadentate (L₁ , L₃ ) or heptadentate (L₂ ) chelation by the ligand, with one water molecule in the inner coordination sphere. The relaxivity was determined from 20 kHz to 30 MHz by fast-field cycli

SUBMITTER: Barre R 

PROVIDER: S-EPMC9544908 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature