14C‐labelling of ipamorelin, a growth hormone secretagogue

Ipamorelin (NNC 26-0161) labelled with 14 C has been synthesised from [ 14 C]α-aminoisobutyric acid in three steps using solid phase chemistry. The overall radiochemical yield was 31%. The radiochemical purity (RCP) was >98% and the specific radioactivity was 57 mCi/mmol.