Complexes of Porphyrins and Related Systems

The structure of Eu(terpy)3 (reproduced by permission of the Royal Society of Chemistry from G.H. Frost, F.A. Hart, C. Heath, and M.B. Hursthouse, Chem. Commun., 1969, 1421). 

Complexes, particularly of gadolinium, with a N4-donor macrocycle backbone that also supports carboxylate groups have assumed importance in the context of MRI contrast agents (Sections 5.5.2 and 5.5.3). 

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