1 R1A 3-{[(2,2,5,5-tetramethyl-1-oxo-2,5-dihydro-1h-pyrrolium-3-yl)methyl]disulfanyl}-D-alanine 1.000 2 3X9 3-{[(1-hydroxy-2,2,5,5-tetramethyl-2,5-dihydro-1h-pyrrol-3-yl)methyl]disulfanyl}-L-alanine 1.000