Figure 1.

OSSL_325096 inhibits multiple myeloma (MM) cell proliferation. A, Chemical structure of OSSL_325096. (R)‐ and (S)‐OSSL_325096 are two stereoisomers (enantiomers) that differ in the configuration of the chiral carbon assigned by the asterisk. Such a simple difference in configuration resulted in a significant difference in bioactivity. B, Antiproliferative activity of OSSL_325096 and DBeQ in MM cell lines. Cells were treated with 0.1% DMSO, 0.05, 0.1, 0.5, 1, 5, or 10 μmol/L OSSL_325096 or DBeQ for 96 h and cell viability was evaluated by WST‐8 assay. Cell viability of DMSO‐treated samples served as a control. C, (S)‐OSSL_325096 showed higher antiproliferative activity than (R)‐OSSL_325096. KMS12PE cells were treated with 100, 25, 6.25, 1.56, or 0.39 μmol/L of R type or S type OSSL_325096 for 96 h and cell viability was evaluated by WST‐8 assay. Data represent the mean ± SD derived from three separate experiments