(2R,4S)-4-((t-Butoxycarbonyl)amino)-2-hydroxy-2,6-dimethyl-3-oxoheptyl Acetate is an intermediate in synthesizing Carfilzomib (2S,4S)-Diol (C183495), a derivative of Carflizomib (C183460), which is a second-generation proteasome inhibitor that is used as a treatment in relapsed and refractory multiple myeloma.