Rufforone: A New Styrylpyrone from Sanrafaelia ruffonammari

A new styrylpyrone, 6-(7-hydroxy-8-methoxystyryl)-4-methoxypyran-2-one (1), together with two known styrylpyrones, 6-(7,8-epoxystyryl)-4-methoxypyran-2-one (2) and 6-(7,8-dihydroxystyryl)-4-methoxypyran-2-one (3) were isolated from the stem bark of Sanrafaelia ruffonammari Verdc. 6-(7,8-Epoxystyryl)-4-methoxypyran-2-one exhibited high inhibitory activity to interferon-γ-induced nitric oxide generation in RAW264.7 macrophages, whereas the other two showed no activity.