7,3＇,4＇-Trihydroxyflavone

7,3',4'-Trihydroxyflavone is a flavonoid identified in Albizia julibrissin bark, known for its diverse biological activities. It acts as a potent scavenger of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and peroxynitrite radicals in cell-free assays, with IC₅₀ values of 2.2 µM and 5.78 µM, respectively. Additionally, it reduces total reactive oxygen species in rat kidney homogenates (IC₅₀ = 3.9 µM). The compound inhibits cyclooxygenase-1 (COX-1) with an IC₅₀ of 36.7 µM and exhibits activity against Mycobacterium tuberculosis (MIC = 50 µg/ml). Furthermore, it suppresses the mRNA expression of key osteoclastic marker genes, including those encoding the calcitonin receptor, cathepsin K, V-ATPase V0 subunit d2 (Atp6vOd2), and dendritic cell-specific transmembrane protein (Dcstamp). It also inhibits RANKL-induced osteoclastic differentiation in mouse bone marrow-derived macrophages (BMDMs).