2,2,6,6-tetramethyl-3,5-bis(methoxycarbonyl)-4-piperidone-1-oxyl

2,2,8,8-tetramethyl-1-(1-phenylethoxy)-4-azocanol

2,2,6,6-tetramethyl-1-p-toluenesulfonyl-4-(p-toluenesulfonyloximo)piperidine

2,2,6,6-tetramethyl-4-p-toluenesulfonyloximinopiperidine-1-oxyl

4-[benzyloxycarbonyl-(2-tert-butoxycarbonylaminoethyl)amino]-2,2,6,6-tetramethylpiperidin-1-oxyl radical