Bioactive Isoflavones from Dalbergia vacciniifolia (Fabaceae)

Abstract

Three new 5-dehydroxy isoflavone compounds, 6,2′-dimethoxy-7,4′-dihydroxyisoflavone (1), 6,2′,4′-trimethoxy-7-hydroxyisoflavone (2), and 6,2′,4′,5′-tetramethoxy-7- O-[β–D-apiofuranosyl-(1→6)-β–D-glucopyranoside] isoflavone (3), along with a known isoflavone, 6,2′,4′,5′-tetramethoxy-7-hydroxyisoflavone (4), were isolated from the ethanolic extract of Dalbergia vacciniifolia Vatke. Their structures were established by spectroscopic techniques including one- and two-dimension NMR. Compound 1 showed mild cytotoxic activity against brine shrimp larvae with a LC₅₀ value of 266 μg/mL