Synthesis of a 11C-labeled novel, quinuclidine based ligand for the 5-HT3 receptor

L-683,877, a high affinity, 5-HT₃ selective receptor ligand has been labeled with ¹¹C for use in PET studies to measure regional brain kinetics of L-683,877 and to determine if [¹¹C]L-683,877 can be used for serotonin 5-HT₃ receptor imaging. [¹¹C]L-683,877 was prepared by reacting [¹¹C]methyl iodide with the desmethyl, borane-protected precursor, L-686,472, in DMF in the presence of tetrabutyl ammonium hydroxide. The average specific activity of [¹¹C]L-683,877 was 2700 Ci/mmol and the average radiochemical yield (decay uncorrected) was 20% at the end of synthesis (22 min from EOB).