CAS No:2734474-72-5||Chemical Formula:C23H27N5O7S ||Molecular Weight:517.55700 ||Exact Mass:517.16312 ||2-(((E)-(2-((R)-(4-ethyl-2,3-dioxopiperazine-1-carboxamido)(phenyl)methyl)-5-oxooxazol-4(5H)-ylidene)methyl)amino)-3-mercapto-3-methylbutanoic acid