Copper(ii) complexes of cyclams with N-(2,2,2-trifluoroethyl)-aminoalkyl pendant arms as potential probes for ¹⁹F magnetic resonance imaging

Abstract

A series of Cu(II) complexes with cyclam-based ligands containing two N-(2,2,2-trifluoroethyl)-aminoalkyl pendant arms in 1,8-positions (L1: 1,2-ethylene spacer, L2: 1,3-propylene spacer; L3: 1,4-butylene spacer) was studied in respect to potential...

Transition metal complexes of cyclam with two 2,2,2-trifluoroethylphosphinate pendant arms as probes for 19F magnetic resonance imaging

“…33 Observed T 1 for the Cu(II)-H 2 L complexes (ca. 5-9 ms) is slightly lower than values found for isomeric Cu(II) complexes of 1,8-(tfe-NHCH 2 CH 2 ) 2 cyclam (7-12 ms) 42 theory. 30 Preliminary calculation confirmed that the contribution of relaxation is set of complexes negligible and, thus, only the dipolar relaxation mechanism was considered.…”

“…5–9 ms) is slightly lower than values found for isomeric Cu( ii ) complexes of 1,8-(tfe-NHCH 2 CH 2 ) 2 cyclam (7–12 ms) 42 whereas the average M⋯F distances found in the Cu( ii )–H 2 L complexes are somewhat longer (6.36 Å) than those observed for the Cu( ii )–1,8-(tfe-NHCH 2 CH 2 ) 2 cyclam (5.6–6.1 Å). 42 However, the signals of the Cu( ii )–H 2 L complexes are very broad. The / T 1 ratio is ca.…”

“…42 It was shown that complexation of Cu( ii ) to these structures shortens significantly fluorine relaxation times to an optimal range (order of tenths of milliseconds). 42 Some time ago, we introduced (2,2,2-trifluoroethyl)phosphinic acid as a suitable pendant arm in the cyclen-based ligand H 4 dotp tfe (Fig. 1) and studied its lanthanide( iii ) complexes.…”

Transition metal complexes of the (2,2,2-trifluoroethyl)phosphinate NOTA analogue as potential contrast agents for 19F magnetic resonance imaging

“…1) containing six fluorine atoms and a study of its transition metal complexes was reported. 47 The results showed that such a concept is viable and brought promising data especially for the Co 2+ complex. 47 Fig.…”

“…47 The results showed that such a concept is viable and brought promising data especially for the Co 2+ complex. 47 Fig. 1 Ligands mentioned in the text.…”