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Fast and reasonable low‐scale (200 nmol) syringe‐made synthesis of¹⁵N‐labeled oligonucleotides representing DNA trinucleotide codons is communicated. All codons were prepared by solid‐phase controlled pore glass synthesis column technique via the phosphoramidite method. Twenty‐four labeled oligonucleotides covering the DNA genetic code alphabet were prepared using commercially available reagents and affordable equipment in a reasonably short period of time, with acceptable yields and purity for direct applications in mass spectrometry. 

The multifunctional radioligand [³H]T0901317 ([³H]1) has been employed as a powerful autoradiographic tool to target several receptors, such as liver X, farnesoid X, and retinoic acid‐related orphan receptor alpha and gamma subtypes at nanomolar concentrations. Although [³H]1is commercially available and its synthesis via tritiodebromination has been reported, the market price of this radioligand and the laborious synthesis of corresponding bromo‐intermediate potentially preclude its widespread use in biochemical, pharmacological, and pathological studies in research lab settings. We exploit recent reports on hydrogen‐isotope exchange (HIE) reactions in tertiary benzenesulfonamides where the sulfonamide represents anortho‐directing group that facilitates CH activation in the presence of homogenous iridium(I) catalysts. Herein, we report a time‐ and cost‐efficient method for the tritium late‐stage labeling of compound1—a remarkably electron‐poor substrate owing to the tertiary trifluoroethylsulfonamide moiety. Under a straightforward HIE condition using a commercially available Kerr‐type NHC Ir(I) complex, [(cod)Ir (NHC)Cl], the reaction with1afforded a specific activity of 10.8 Ci/mmol. Additionally, alternative HIE conditions using the heterogeneous catalyst of Ir‐black provided sufficient 0.72 D‐enrichment of1but unexpectedly failed while repeating with tritium gas.