Labdane-type diterpenes and flavones from Dodonaea viscosa.

A new labdane diterpenoid, 2,18-dihydroxylabda-7,13(E)-dien-15-oic acid (1), together with two known labdane diterpenes (3, 4), a new flavone, 5,7-dihydroxy-3,6,4'-trimethoxy-3'-(4-hydroxy-3-methyl-but-2-enyl)flavone (2) with three known flavones (5-7) were isolated from the aerial parts of Dodonaea viscosa. Their structures were determined by extensive analysis of spectroscopic data (1D and 2D NMR, MS) and by comparison with literature data. The anti-inflammatory activity of five compounds (1-5) was evaluated with a flow cytometry TNF-α secretion assay on human THP-1 cell line.