New labelling-strategies



Synthesis of 2-[18F]Fluoroethylamine:

Starting from N,N-(dibenzyl)-aminoethyltosylate, the labelling synthon 2-[18F]fluoroethylamine is produced in a two step reaction. In principle, it can be used for the radioactive labelling via carboxylic functions by forming a 18F-labelled acid amide e.g. for binding to the C-terminals of peptides.

in situ synthesis of 2-iodo-[18F]fluoroethane:

By addition of iodide compounds to the established secondary precursors 2-bromo-[18F]fluoroethane and 2-[18F]fluoroethyltosylate, 2-Iode-[18F]fluoroethane is formed in situ, which is, due to the high nucleophilicity of the iodine, a better alcylating agent than its educts. That is why this in situ synthesis was analyzed systematically at the Mainz Institute of Nuclear Chemistry. The reaction conditions were optimized to increase the alcylating yield of many different radiopharmaceuticals.

 

Synthesis of N-([18F]fluoroalkyl)-N-nitroso-4-methyl-benzenesulfonamids:

Theoretically these compounds are able to release 18F-labelled diazoalkanes under alkaline conditions. It is possible to 18F-label acetic fluoro-alcylatable groups like carboxy or phenolic HO functions using diazoalkanes. The advantage of this procedure is that there is no need to protect higher nucleophilic groups like amino functions. This would eventually be an advantage compared to established 2-[18F]fluoroethyltosylate.

Synthesis of 72As-labelled amino acids, peptides and proteins:

 

Synthesis of bifunctional Chelators:

These Copounds are able to complex Arsen and bind to amino acids (e.g. trosin), peptides (e.g. octreotid) and antibodies.