A general method for the fluorine‐18 labelling of fluoroquinolone antibiotics

Abstract

SummaryFluoroquinolones are an important class of antibiotic agents with a broad spectrum of antibacterial activity. Labelling of fluoroquinolones with fluorine-18 is of interest for the performance of pharmacokinetic measurements and the visualization of bacterial infections in humans with positron emission tomography. A two-step radiosynthetic pathway to prepare fluorine-18-labelled ciprofloxacin (1-cyclopropyl-6-[18 F]fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-quinoline-3-carboxylic acid) has previously been developed. In the present work this approach was applied to the preparation of the structurally related compounds [

Chronic Urticaria and Parasitic Infections

“…Since the 6-position of the carboxylic acid was only moderately activated for nucleophilic substitution high temperature (175°C) and long reaction times (40 min) were required. In the second step of the synthesis, an in-situ generated boron complex of 7-chloro-1-cyclopropyl-6-[ 18 F]fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (Langer et al, 2003b) was reacted with piperazine to yield [ 18 F]ciprofloxacin. 2.…”

Épidémiologie et anatomie des cancers ORL

“…However, as [ 18 F]ciprofloxacin will be used to study the tissue distribution of ciprofloxacin at therapeutic doses and as ciprofloxacin is a marketed drug with a good safety profile, high specific activity of [ 18 F]ciprofloxacin is not mandatory. In the second step of the synthesis, an in-situ generated boron complex of 7-chloro-1-cyclopropyl-6-[ 18 F]fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (Langer et al, 2003b) was reacted with piperazine to yield [ 18 F]ciprofloxacin. Crude product was purified by semipreparative HPLC (Fig.…”

19F/18F exchange synthesis for a novel [18F]S1P3‐radiopharmaceutical

“…Previously, direct 19 F/ 18 F isotope exchange reactions have been applied to 18 F‐fluorination of small aromatic molecules. 18 F‐Labeling of larger molecules with 19 F/ 18 F isotope exchange reaction has been reported to be more difficult, and commonly, these molecules have been produced with at least a two‐step synthesis where protecting groups were needed or by coupling a 18 F‐labeled small molecule with a larger molecule . In this study, [ 18 F] 1 was synthesized using one‐step synthesis and 19 F/ 18 F isotope exchange reaction (Figure ).…”

“…The 19 F/ 18 F isotope exchange reaction allows the labeling of drug molecules that contain fluorine in their molecular structure. Several 19 F/ 18 F isotope exchange studies examined the effects of the molecular structure of the precursor and have investigated the reaction kinetic parameters to optimize radiochemical yield and specific activity . Most of these studies have been performed using relatively small amounts of initial activity of 18 F‐fluorine, and precursor compounds have mostly been relatively simple small molecules …”