Twelve new diterpenoids based on two rare skeletal types, namely, paralianones A-D (1-4) and pepluanols A-H (5-12), along with five known compounds, were isolated from an acetone extract of Euphorbia peplus. Their structures were proposed based on 1D and 2D NMR spectroscopic data analysis. These diterpenoids were evaluated for potential anti-inflammatory activity in a lipopolysaccharide-stimulated mouse macrophage cellular model. Compounds 3, 4, 11, 13, and 16 displayed moderate inhibitory effects on NO inhibition, with IC50 values ranging from 29.9 to 38.3 μM.

Five new ent-kaurane diterpenoids, named mascaroside III–V (1–3), and 20-nor-cofaryloside I–II (4–5), together with seven known diterpenoids, were isolated from methanol extracts of the green coffee beans of Yunnan Arabica Coffee. Their chemical structures were elucidated by extensive spectroscopic analyses. Meanwhile, cytotoxicity assay against HL-60, A-549, SMMC-7721, MCF-7 and SW480 cell lines showed that they have not evident inhibition of cytotoxicity.Graphical AbstractElectronic supplementary materialThe online version of this article (doi:10.1007/s13659-016-0099-1) contains supplementary material, which is available to authorized users.

Three new limonoid-type triterpenoids, namely toonasins A–C (1–3) with a rare lactam E ring, along with six known compounds (4–9) were isolated from the barks of Toona sinensis. The structures of new compounds were elucidated by interpretation of spectroscopic data, and the relative configuration of compound 1 was further characterized by X-ray crystallographic analyses. The isolated compounds were evaluated for their cytotoxic activities against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW480), and compounds 3 and 5 showed weak cytotoxicities.Electronic supplementary materialThe online version of this article (doi:10.1007/s13659-016-0108-4) contains supplementary material, which is available to authorized users.