No‐carrier‐added, ¹⁸F‐labelling of a cholesterol derivative, used in detection of adrenal malignancies

Abstract

Summary[ 18 F]Cholesteryl 4-(fluoromethyl)benzoate 6b was prepared from 3-cholesteryl [(4-nitrobenzenesulfonyl)oxymethyl]benzoate in one step using K + -Kryptofix 2.2.2, as counter ion and acetonitrile as the solvent at 40-608C. The product was isolated by HPLC in 75% (decay corrected) radiochemical yield with a radiochemical purity of more than 90% in 30 min (specific radioactivity 2000-2500 Ci/mmol). Biodistribution studies in mice showed that a high target/non-target ratio of radioactivity was obtained in adrenal and ovaries.

Radiosynthesis of dimethyl-2-[18F]-(fluoromethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate for L-type calcium channel imaging

“…Based on our previous works on the production and biological evaluation of fluorine-18 labeled compounds such as cholesteryl esters [12], benzodiazepine ligands [13] and with respect to our other research project on the interesting biological actions of dihydropyridines [14], we decided to prepare a 18 F-labeled nifedipine analogue 4b. The synthesis utilizes commercially available nifedipine 1, to obtain, […”