Synthesis of [1,2‐3H]ethylamine hydrochloride and [3H]‐labeled apadenoson for a human ADME study

Tritium‐labeled [1,2‐³H]ethylamine hydrochloride was prepared through a multiple‐step sequence in high radioactive specificity. The labeled amine was isolated in high purity following cartridge filtration and used subsequently in the synthesis of [N‐ethyl‐1,2‐³H]apadenoson, an adenosine A_2a receptor agonist. The overall yield for this transformation was 56% and the radiochemical purity of the final product was greater than 99%. Copyright © 2008 John Wiley & Sons, Ltd.