Sucrosephenylpropanoid esters and isoflavonoids isolated from Belamcanda chinensis roots and their potential anti-osteoclastogenic activity

Repeated chromatography of the CH₂Cl₂ and EtOAc soluble fractions from the methanol extract of Belamcanda chinensis root yielded six new sucrosephenylpropanoid esters (1–6) and twenty-one known compounds (7–27). The structures of 1–6 were elucidated using diverse nuclear magnetic resonance (NMR) techniques and high-resolution mass spectrometry (HRMS) data analysis, together with chemical methods. All the twenty-seven isolated compounds were evaluated for their anti-osteoclastogenic activities. Preliminary screening results revealed that compounds 1 and 19 exhibited strong effects against RANKL-induced osteoclast formation in RAW264.7 cells. In addition, the treatment of mouse bone marrow macrophages (BMMs) with compounds 1 and 19 significantly decreased RANKL-induced TRAP-positive multinucleated osteoclast formation in a concentration-dependent manner without affecting cell viability. Further bioassay investigation showed that compounds 1 and 19 inhibited the expression of some osteoclast-specific marker genes and the transcription factor nuclear factor of activated T cells cytoplasmic 1 (NFATc1) in response to RANKL. To the best of our knowledge, this is the first investigation of anti-osteoclastogenic activity for compounds isolated from B. chinensis.