Synthesis and characterization of 2,6-difluoro-4-carboxyphenylboronic acid and a biotin derivative thereof as captors of anionic aqueous [F-18]-fluoride for the preparation of [F-18/F-19]-labeled aryltrifluoroborates with high kinetic stability

Arylboronic esters are readily converted to aryltrifluoroborates in the presence of aqueous fluoride. As such these represent attractive synthetic precursors that afford one-step labeling with [F-18]-fluoride for the generation of PET reagents. Herein we present the synthesis of a heretofore undisclosed arylboronic ester that is converted to its corresponding trifluoroborate. Essential for contemplating its use in PET imaging is the demonstration of kinetic resistance to solvolytic defluoridation. (C) 2008 Published by Elsevier Ltd.