Adenanthera pavonina L. has been used traditionally to relieve inflammation. This study aimed to expand the phytochemical knowledge of A. pavonina and evaluate its constituents for their antioxidant and anti-inflammatory potentials as tumor necrosis factor alpha (TNF-a) inhibitors. The antioxidant activity was evaluated using the DPPH radical scavenging assay, and the inhibition of TNF-a was assessed through ELISA and qRT-PCR techniques. Interestingly, five previously undescribed metabolites, including a pentadienoic acid derivative, a triterpenoid glycoside, and three tamarixetin glycosides, were identified alongside seven known compounds. Most compounds evaluated had higher DPPH radical scavenging capabilities than the standard, trolox. Tamarixetin 3-O-(a-ʟ -rhamnopyranosyl)-(1!2)-b-ᴅ-galactopyranoside (11), a previously undescribed compound, was the most effective at suppressing TNF-a protein and m-RNA levels. Other flavonoid glycosides,
quercetin 3-O-(a-ʟ-rhamnopyranosyl-(1!2)-b-ᴅ-xylopyranoside (4), isovitixin (5), and quercetin-3-O-[a-ʟ -rhamnopyranosyl-(1!2)]-[a-ʟ-rhamnopyranosyl-(1!6)]-b-ᴅ -galactopyranoside (9), also significantly lowered TNF-a production.