1 R1F S-[(1-oxyl-2,2,5,5-tetramethyl-4-phenyl-2,5-dihydro-1h-pyrrol-3-yl)methyl] methanesulfonothioate 1.000 2 MTN S-[(1-oxyl-2,2,5,5-tetramethyl-2,5-dihydro-1h-pyrrol-3-yl)methyl] methanesulfonothioate 0.727