2049025-67-2

(αS)-α-[[2-(4-Morpholinyl)acetyl]amino]benzenebutanoyl-L-leucyl-N-[(1R)-3-methyl-1-[[(2S)-2-methyl-2-oxiranyl]carbonyl]butyl]-L-phenylalaninamide is an impurity of Carfilzomib (C183460), which is a second-generation proteasome inhibitor that is used as a treatment in relapsed and refractory multiple myeloma.