A new oleanane type triterpenoid from Viburnum taitoense Hayata

The chemical constituents of Viburnum taitoense Hayata were investigated using column chromatography silica gel and Sephadex LH-20, etc. Seven pentacyclic triterpenoids were isolated and their structures were elucidated by spectral data and physicochemical properties as 3β,6β-dihydroxy olean-11,13(18)-dien-28-acid (1), 3β-hydroxy olean-11,13(18)-diene-28-acid (2), 12-ene-olean-28-acid-3β-palmitate (3), 3β-acetylcocodiol (4), corosolic acid (5), uvaol (6) and ursolic acid (7). Among them, compound 1 is a new oleanane type triterpenoid and its absolute configuration was confirmed by single-crystal X-ray diffraction data. Compounds 2-5 were isolated from this genus for the first time. All the compounds were evaluated for their anti-inflammatory activities in vitro, and compound 5 showed significant inhibitory activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with an IC₅₀ of 25.52 ±0.56 μmol·L^-1 when compared to the positive control, quercetin (IC₅₀ of 25.46 ±0.62 μmol·L^-1).