Horsfielenigans A and B, Two Rearranged Lignans with Anti-Inflammatory Effects from Horsfieldia kingii.

Seven lignans were isolated from 70 % aqueous acetone extracts of the twigs and leaves of Horsfieldia kingii. Among these, new compounds 1-3 were identified by spectroscopic techniques, with horsfielenigans A and B (1 and 2) being particularly noteworthy for their rare ß-benzylnaphthalene skeleton, where compound 1 contains an oxabicyclo[3,2,1]octane moiety. In vitro evaluation of bioactivity against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages revealed inhibitory effects by 1 (IC50 =7.3 µM) and 2 (IC50 =9.7 µM).