Synthesis of 15N-enriched pseudouridine derivatives

reaction: see text]. A procedure for the chemical synthesis of 3-15N]-labeled pseudouridine and a methylated derivative was developed. A suitably protected pseudouridine precursor was nitrated at N3 followed by treatment with 15NH4Cl to afford the 15N-labeled product in six steps with a 20% yield. This methodology will allow for the production of RNAs with 3-15N]pseudouridine and 3-15N-methyl]pseudouridine at specific locations.