Synthesis and HNO Donating Properties of the Piloty's Acid Analogue Trifluoromethanesulphonylhydroxamic Acid: Evidence for Quantitative Release of HNO at Neutral pH Conditions

Trifluoromethanesulphonylhydroxamic acid, CF3SO2NHOH, is shown to release HNO under physiological pH conditions. A two‐step synthesis is presented with the first complete characterization of CF3SO2NHOH. This molecule rapidly decomposes in neutral aqueous solution to cleanly release HNO and CF3SO2−, which was demonstrated using the HNO traps TXPTS and HOCbl, and by 19F NMR spectroscopy. Simple and clean HNO generator: The trifluoromethanesulphonyl analogue of the well‐established HNO donors methanesulphohydroxamic acid (MSHA) and benzenesulphohydroxamic acid (Piloty's acid) has been synthesized. Unlike MSHA and Piloty's acid, CF3SO2NHOH is an excellent HNO generator at neutral pH conditions, stoichiometrically releasing HNO and the benign CF3SO2− side product.