New coumarins and anti-inflammatory constituents from Zanthoxylum avicennae

Zanthoxylum avicennae is commercially used as healthcare products for the improvement of chronic hepatitis and rheumatism. Its fruit is also used as a spice. Five new coumarins, 5′-methoxyauraptene (1), 6,5′- dimethoxyauraptene (2), 5′-methoxycollinin (3), 7-((2′E,5′E)- 7′-methoxy-3′,7′-dimethylocta-2′,5′-dienyloxy) coumarin (4), and 6-methoxy-7-((2′E,5′E)-7′-methoxy-3′, 7′-dimethylocta-2′,5′-dienyloxy)coumarin (5), have been isolated from the leaves of Z. avicennae, together with 15 known compounds (6-20). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 6, 9-15, and 18 exhibited inhibition (IC ₅₀ ≤ 8.29 μg/ml) of superoxide anion generation by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/ cytochalasin B (fMLP/CB). Compounds 6, 10, 12, 14, and 18 inhibited fMLP/CB-induced elastase release with IC ₅₀ values ≤6.30 μg/ml.