N-(2-carboxyethyl)-N-[2-(2,5-dihydro-2,5-dioxo-1H-

N-(2-Carboxyethyl)-N-[2-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)ethyl]-,mono(4-methylbenzenesulfon-ate) B-alanine