Three new iridoids from two Viburnum species

Three new iridoids, 10-deacetyl suspensolide A aglycone (1), 7-deacetyl suspensolide A aglycone (2), and 7,10-dideacetyl suspensolide A aglycone (3), were isolated from two species of Viburnum. Their structures were elucidated on the basis of spectroscopic methods, including 1D and 2D NMR techniques. Compound 2 exhibited moderate anti-inflammatory activity against NO production in LPS-stimulated RAW 264.7 cells with IC50 of 17.2 μM.