Universität Tübingen
Studies on the Nucleophilic Aromatic 18F-Fluorination- From Model Compounds to Aromatic Amino Acids
Abstract
The objective of this work was to develop a new strategy aiming at the syntheses of n.c.a. 18F-labeled aromatic amino acids via three steps, i.e. nucleophilic 18F-labeling, decarbonylation and hydrolysis. First, systematic investigations on nucleophilic aromatic 18F-fluorination was performed by using a variety of model compounds exhibiting different substitution patterns with both +M (-MeO or -Me) and -M substituents (leaving group (-LG) or -CHO). Secondly, the optimized decarbonylation condition was determined by decarbonylating the 18F-labeled model compounds. In overall synthesis, a proof-of-principle study on the synthesis of [18F]fluoro-p-tyrosine proved the three-step synthetic strategy to be suitable for syntheses of 18F-labeled aromatic amino acids. However, in the case of the precursor with low reactivity toward SNAr ([18F]fluoro-m-tyrosine and [18F]FDOPA), further optimization of the organic synthesis of precursors is in progress. In the last part, an automated synthesis of [18F]FDOPA over four steps (fluorination, reductive iodination, alkylation and hydrolysis), as described in the literature, was brought into routine application for the first time. 9064 ± 3076 MBq of [18F]FDOPA could be produced within 120 min of production time from EOB (n = 5). The radiochemical purity and enantiomeric purity were both 95 %. The specific activity was ca. 50 GBq/µmol at EOS.
Author and committee
dc:creator, dc:contributor.*- Author
-
- Shen, Bin
Identifiers
dc:identifier.*- Identifier
- hdl:10900/49234