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Preparation and Evaluation of 99mTc-labeled Tridentate Chelates for Pre-targeting Using Bioorthogonal Chemistry
Published on: February 4, 2017
Oxotechnetium(V) complexes with a novel class of tridentate thiosemicarbazide ligands
Hung Huy Nguyen1, Pedro I da S Maia, Victor M Deflon
1Institute of Chemistry and Biochemistry, Freie Universitat Berlin, Fabeckstrasse 34-36, D-14195 Berlin, Germany.
Abstract:
A novel tridentate thiosemicarbazide-type ligand class with an SNS donor set, H(2)L(1), was prepared by reactions of N-[N',N'-dialkylamino(thiocarbonyl)]benzimidoyl chlorides with thiosemicarbazides. H(2)L(1) ligands readily react with (NBu(4))[TcOCl(4)] in MeOH under the formation of red oxotechnetium(V) complexes of composition [TcOCl(L(1))]. The monomeric, five-coordinate compounds are air-stable and bind (L(1))(2-) tridentate in the equatorial coordination sphere. The compounds represent the first examples of oxotechnetium(V) complexes with NS chelate-bonded thiosemicarbazones.
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