Efficient synthesis of the ¹⁸F-labelled amino acid 3-O-methyl-6-[¹⁸F]fluoro-L-DOPA

The ¹⁸F-labelled amino acid derivative 3-O-methyl-6-[¹⁸F]fluoro-L-DOPA ([¹⁸F]OMFD) is a potential radiotracer to image tumour tissue using positron emission tomography. The precursor N-formyl-3-O-methyl-4-O-boc-6-trimethyl-stannyl-L-DOPA--ethyl ester enables the direct electrophilic radiofluorination by stereoselective destannylation. After partial hydrolysis, an optimized HPLC purification and sterile filtration the [¹⁸F]OMFD obtained with high radiochemical purity is ready for use. The total synthesis time is about 50 minutes and the radiochemical yield achieved is 20-25% (decay corrected, related to [¹⁸F]F₂). It was demonstrated that [¹⁸F]OMFD can be produced routinely and reliably for clinical use. [¹⁸F]FDOPA - preparation devices can be used with minor modifications.