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Updated: Sep 27, 2026

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging
Published on: December 4, 2016
The CoIII-C bond in (1-thia-4,7-diazacyclodecyl-kappa3N4,N7,C10)(1,4,7-triazacyclononane-kappa3N1,N4,N7)cobalt(III)
Pernille Harris1, Pauli Kofod, Yong Sheng Song
1Centre for Crystallographic Studies, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark. ph@kemi.dtu.dk
Abstract:
In the title compound, [Co(C(6)H(15)N(3))(C(7)H(15)N(2)S)]S(2)O(6).H(2)O, the Co-C bond distance is 1.9930 (13) A, which is shorter than for related compounds with the linear 1,6-diamino-3-thiahexan-4-ide anion in place of the macrocyclic 1-thia-4,7-diazacyclodecan-8-ide anion. The coordinated carbanion produces an elongation of 0.102 (7) A of the Co-N bond to the 1,4,7-triazacyclononane N atom in the trans position. This relatively small trans influence is presumably a result of the triamine ligand forming strong bonds to the Co(III) atom.
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