High specific activity tritium-labeled N-(2-methoxybenzyl)-2,5-dimethoxy-4-iodophenethylamine (INBMeO): A high-affinity 5-HT2A receptor-selective agonist radioligand Original Research Article

The title compound ([3H]INBMeO) was prepared by an O,O-dimethylation reaction of a t-BOC protected diphenolic precursor using no carrier added tritiated iodomethane in DMF with K2CO3. Removal of the t-BOC protecting group and purification by HPLC afforded an overall yield of 43%, with a radiochemical purity of 99% and specific activity of 164 Ci/mmol. The new radioligand was suitable for labeling human 5-HT2A receptors in two heterologous cell lines and had about 20-fold higher affinity than [3H]ketanserin.