4-Amino-TEMPO-d17 (4-Amino-2,2,6,6-tetramethylpiperidine-1-oxyl-d17) is the deuterium labeled 4-Amino-TEMPO (HY-W002004). 4-Amino-TEMPO (4-Amino-2,2,6,6-tetramethylpiperidine-1-oxyl) is a stable nitroxide radical and N-nucleophile based on TEMPO. 4-Amino-TEMPO has superoxide dismutase-mimetic activity, can protect cells from oxidative damage, and has radioprotective effects. 4-Amino-TEMPO is widely used in fields such as biomedicine, materials science, and industrial production. 4-Amino-TEMPO can be used as a spin label to detect free radicals, an oxidation catalyst in industrial production, and an antioxidant stabilizer for polymers, among others[1][2].