(2S)-2'-Methoxykurarinone, a compound isolated from the roots of Sophora flavescens , has anti-inflammatory, antipyretic, antidiabetic, and antineoplastic effects. (2S)-2'-Methoxykurarinone (MK) inhibits osteoclastogenesis and bone resorption through down-regulation of RANKL signaling. (2S)-2'-Methoxykurarinone (MK) displays cytotoxic activity against human myeloid leukemia HL-60 cells.