(-)-CMLD010509 ((-)-SDS-1-021) is an isomer of CMLD010509 (SDS-1-021). CMLD010509 (SDS-1-021) is a highly specific inhibitor of the oncogenic translation program supporting multiple myeloma (MM)-including key oncoproteins such as MYC, MDM2 , CCND1, MAF, and MCL-1. CMLD010509 (SDS-1-021) shows an IC 50 below 10 nM for most MM cell lines and induces apoptosis. CMLD010509 (SDS-1-021) is a potent and selective translation inhibitor through an eIF4E phosphorylation-independent mechanism.