Utility of 1,3,4,6‐tetra‐O‐acetyl‐2‐deoxy‐2‐[¹⁸F]fluoro‐glucopyranoside for no‐carrier‐added ¹⁸F‐glycosylation of amino acids

A radiochemical method for the 18 F‐glycosylation of amino acid side chains was developed starting from peracetylated 2‐deoxy‐2‐[ 18 F]fluoroglucopyranoside (TA‐[ 18 F]FDG). O ‐(2‐deoxy‐2‐[ 18 F]fluoro‐ D ‐glucopyranosyl)‐ L ‐serine and the corresponding threonyl compound were obtained in a radiochemical yield of 25% and 12% (related to [ 18 F]fluoride), respectively, after Zemplén deprotection within a total reaction time of 90 min. The anomeric configuration of the corresponding 19 F‐substituted compounds revealed preferential α ‐stereoselectivity. The 18 F‐glycosylation method using TA‐[ 18 F]FDG is compatible with the short half‐life of fluorine‐18 and combines glycosylation and 18 F‐labelling of a target compound within a single reaction step. TA‐[ 18 F]FDG is a promising 18 F‐labelled prosthetic group and could be adapted to 18 F‐labelling of bioactive peptides to study their pharmacokinetics using positron emission tomography (PET).