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Thirty-three natural products were isolated from the aerial parts of Antidesma bunius, Euphorbiaceae, a plant used in Vietnamese traditional medicine against rheumatoid arthritis. All compounds were reported the first time for this species, and nine constituents resembled undescribed natural products, noticeably three coumarinolignans with 2,2-dimethyl-1,3-dioxolane moiety, two cyclopeptides, and two furofuran-type lignans connected with a phenylpropanoid moiety. The individual structures were elucidated by combining NMR and MS data, and their configuration was established by NOESY and ECD experiments and NMR calculations. Compounds with sufficient amount were analyzed for their inhibition of advanced glycation endproducts (AGEs) formation, metabolites involved in many diseases like Alzheimer, joint diseases or diabetes. With IC

Two xanthones, namely virgataxanthone A and B, have been isolated from the stem bark of Garcinia virgata, together with two formylated tocotrienols and the known delta-tocotrienol, griffipavixanthone and 2,6-dihydroxy-4-methoxybenzophenone (cotoin). Their structures were mainly established using one and two-dimensional NMR and mass spectroscopies. When sufficient material was available, the antioxidant activities of the crude extracts as well as the isolated compounds were evaluated.

A new tirucallane triterpene, (−)-leucophyllone, was isolated from the stem bark of Aglaia leucophylla and its structure was elucidated from spectral data as 23( Z )-25-methoxy-tirucall-7,23-diene-3-one. In addition, (−)-caryophyllene oxide, (−)-niloticin, (−)-bourjotinolone and (−)-piscidinol were isolated from the same plant.

Bioactivity guided fractionation of an ethanolic extract of the stem bark of Aglaia leucophylla led to the isolation of two new 3,4-secotirucallane type triterpenoids, namely (24 Z )-3,4-secotirucalla-4(28),7,24-triene-3,26-dioic acid and its 3-monomethyl ester, together with five known triterpenoids [(+)-ocotillone, (+)-ocotillol, (+)-cabraleone, (+)-cabralealactone and (+)-eichlerianic acid] and one known sesquiterpene [(−)-caryophyllene oxide].

Six coumarins have been isolated from the fruits and the stem bark of Calophyllum dispar (Clusiaceae). The structures of these minor components were established by means of spectroscopic analysis, including extensive 2D NMR studies. Some of these coumarins exhibited a significant cytotoxic activity against KB cells.