Carfilzomib (2S,4S)-Diol Hydrochloride, the salt form of Carfilzomib (2S,4S)-Diol (C183495), and a derivative of Carflizomib (C183460), a second-generation proteasome inhibitor that is used as a treatment in relapsed and refractory multiple myeloma. Molecular Formula: C40H59N5O8 ? HCl Solubility: Methanol (Slightly) Molecular Weight: 737.93