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[ 18 F]FLUDA is a selective radiotracer for in vivo imaging of the adenosine A 2A receptor (A 2A R) by positron emission tomography (PET). Promising preclinical results obtained by neuroimaging of mice and piglets suggest the translation of [ 18 F]FLUDA to human PET studies. Thus, we report herein a remotely controlled automated radiosynthesis of [ 18 F]FLUDA using a GE TRACERlab FX2 N radiosynthesizer. The radiotracer was obtained by a one-pot two-step radiofluorination procedure with a radiochemical yield of 9±1%, a radiochemical purity of ≥99%, and molar activities in the range of 69-333 GBq/μmol at the end of synthesis within a total synthesis time of approx. 95 min (n = 16). Altogether, we successfully established a reliable and reproducible procedure for the automated production of [ 18 F]FLUDA., (© 2022 The Authors. Journal of Labelled Compounds and Radiopharmaceuticals published by John Wiley & Sons Ltd.)

Monocarboxylate transporters 1 and 4 (MCT1 and MCT4) are involved in tumor development and progression. Their expression levels are related to clinical disease prognosis. Accordingly, both MCTs are promising drug targets for treatment of a variety of human cancers. The noninvasive imaging of these MCTs in cancers is regarded to be advantageous for assessing MCT-mediated effects on chemotherapy and radiosensitization using specific MCT inhibitors. Herein, we describe a method for the radiosynthesis of [ 18 F]FACH ((E)-2-cyano-3-{4-[(3-[ 18 F]fluoropropyl)(propyl)amino]-2-methoxyphenyl}acrylic acid), as a novel radiolabeled MCT1/4 inhibitor for imaging with PET. A fluorinated analog of α-cyano-4-hydroxycinnamic acid (FACH) was synthesized, and the inhibition of MCT1 and MCT4 was measured via an L-[ 14 C]lactate uptake assay. Radiolabeling was performed by a two-step protocol comprising the radiosynthesis of the intermediate (E)/(Z)-[ 18 F]tert-Bu-FACH (tert-butyl (E)/(Z)-2-cyano-3-{4-[(3-[ 18 F]fluoropropyl)(propyl)amino]-2-methoxyphenyl}acrylate) followed by deprotection of the tert-butyl group. The radiofluorination was successfully implemented using either K[ 18 F]F-K 2.2.2 -carbonate or [ 18 F]TBAF. The final deprotected product [ 18 F]FACH was only obtained when [ 18 F]tert-Bu-FACH was formed by the latter procedure. After optimization of the deprotection reaction, [ 18 F]FACH was obtained in high radiochemical yields (39.6 ± 8.3%, end of bombardment (EOB) and radiochemical purity (greater than 98%)., (© 2019 John Wiley & Sons, Ltd.)