Sesquiterpene derivatives from Callicarpa longifolia Lam

From the MeOH residue of Callicarpa longifolia Lam. branches and leaves, three new humulane-type sesquiterpenes, namely callicarpols A - C (1 - 3), and one known eudesmane derivative 3α,5β-dihydroxy-β-costol (4), were isolated using various chromatographic techniques. Their structures were confirmed by spectroscopic methods including 1D, 2D NMR and HR-TOF-MS. The relative configurations of 1 - 3 were suggested by NOESY interactions. Moreover, 1 exhibited moderate inhibitory effect on LPS-induced NO generation in RAW264.7 cells with an IC₅₀ value of 39.03 ± 4.04 µM, whereas 4 revealed weak effect with an IC₅₀ value of 88.75 ± 3.44 µM.