Inside Cover: Stable Isotope Phosphate Labelling of Diverse Metabolites is Enabled by a Family of 18O‐Phosphoramidites (Angew. Chem. Int. Ed. 5/2022)

18O-labelled condensed phosphates can be synthesized with a family of 18O-phosphoramidite reagents, as reported by Henning J. Jessen and co-workers in their Research Article (e202112457). “Heavy” phosphoramidites, based on a 4-hydroxyphenol core, are equipped with 18O-isotopes derived from H218O. The toolbox includes a versatile array of protecting groups, removable by acid, base, or fluoride upon self-immolation of a quinone methide. Straightforward access to major classes of biologically relevant 18O-phosphorylated metabolites is demonstrated, including nucleotides, inositol phosphates, and inorganic polyphosphates.