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Updated: Jul 14, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Metal complexes of cyclen and cyclam derivatives useful for medical applications: a discussion based on thermodynamic
Rita Delgado1, Vítor Félix, Luís M P Lima
1Instituto de Tecnologia Química e Biológica, UNL, Apartado 127, 2781-901, Oeiras, Portugal. delgado@itqb.unl.pt
Abstract:
A series of the most common chelators used in magnetic resonance imaging (MRI) and in radiopharmaceuticals for medical diagnosis and tumour therapy, H(4)dota, H(4)teta, H(8)dotp and H(8)tetp, is examined from a chemical point of view. Differences between 12- and 14-membered tetraazamacrocyclic derivatives with methylcarboxylate and methylphosphonate pendant arms and their chelates with divalent first-series transition metal and trivalent lanthanide ions are discussed on the basis of their thermodynamic stability constants, X-ray structures and theoretical studies.
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