7,3',4'-Trihydroxyflavone is a flavonoid that has been found in A. julibrissin bark and has diverse biological activities.1,2,3,4 It scavenges 2,2-diphenyl-1-picrylhydrazyl and peroxynitrite radicals in cell-free assays (IC50s = 2.2 and 5.78 μM, respectively), as well as reduces total reactive oxygen species in rat kidney homogenates (IC50 = 3.9 μM).1 7,3',4'-Trihydroxyflavone inhibits COX-1 (IC50 = 36.7 μM).2 It is active against M. tuberculosis (MIC = 50 μg/ml).3 It decreases mRNA expression of the osteoclastic marker genes encoding the calcitonin receptor, cathepsin K1 V-ATPase V0 subunit d2 (Atp6v0d2), and dendritic cell specific transmembrane protein (Dcstamp) in and inhibits RANKL-induced osteoclastic differentiation of mouse bone marrow-derived macrophages (BMDMs).4

|1. Jung, M.J., Chung, H.Y., Kang, S.S., et al. Antioxidant activity from the stem bark of Albizzia julibrissin. Arch. Pharm. Res. 26(6), 458-462 (2003).|2. Selvam, C., Jachak, S.M., and Bhutani, K.K. Cyclooxygenase inhibitory flavonoids from the stem bark of Semecarpus anacardium Linn. Phytother. Res. 18(7), 582-584 (2004).|3. Chokchaisiri, R., Suaisom, C., Sriphota, S., et al. Bioactive flavonoids of the flowers of Butea monosperma. Chem. Pharm. Bull. (Tokyo) 57(4), 428-432 (2009).|4. Kang, J.H., Lee, J., Moon, M., et al. 3'4'7-Trihydroxyflavone inhibits RANKL-induced osteoclast formation via NFATc1. Pharmazie 70(10), 661-667 (2015).