Two new minor silvestrol analogues [2‴-epi-silvestrol (1) and 2‴,5‴-diepi-silvestrol (2)], together with a new 21-norbaccharane-type triterpene (3), two new 3,4-seco-dammarane triterpenes (4 and 5), and a new eudesmane sesquiterpene (6), as well as nine known compounds, were isolated from a large-scale recollection of the CHCl3-soluble extract of the stem bark of Aglaia foveolata obtained in Kalimantan, Indonesia. The structures of the new compounds were established by interpretation of their spectroscopic data. All of the isolates were tested for cytotoxicity against HT-29 cells. The new silvestrol analogues, 1 and 2, were considerably less active as cytotoxic agents than silvestrol (7) and episilvestrol (5‴-epi-silvestrol) (8), against this cell line, showing the importance of the configuration at C-2‴ in mediating such activity within this compound class. Several of the compounds isolated were also evaluated in a NF-κB (p65) inhibition assay.

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Aim The role of long-distance dispersal in the Indomalesian, Australasian and Pacific flora is currently hotly debated. The lack of well-resolved phylogenetic trees for Pacific plants has been a major limitation for biogeographical analysis. Here, we present a well-resolved phylogenetic tree for the tribe Aglaieae in the mahogany family, Meliaceae, and use it to investigate the origin, evolution and dispersal history of biotas in this area. The subfamily Melioideae, including the tribe Aglaieae (Meliaceae, Sapindales), is a plant group with good representation in the region in terms of biomass and species numbers, wide ecological attributes and known animal vectors. The family has a good fossil record (especially from North America and Europe). Genera and species in the tribe Aglaieae therefore provide an excellent model group for addressing this debate.Location Indomalesia, Australasia, Pacific islands.Methods Results from nuclear internal transcribed spacer ribosomal DNA analyses of 82 taxa, based on sequence alignment guided by secondary structure models, were combined with evidence from fossils and distribution data. We used strict and relaxed molecular clock approaches to estimate divergence times within Aglaieae. Putative ancestral areas were investigated through area-based and eventbased biogeographical approaches. Information on dispersal routes and their direction was inferred from the investigation of dispersal asymmetries between areas.Results Our study indicates that the crown group of Aglaieae dates back at least to the Late Eocene, with major divergence events occurring during the Oligocene and Miocene. It also suggests that dispersal routes existed during Miocene-Pliocene times from the area including Peninsular Malaysia, Sumatra and Borneo to Wallacea, India and Indochina, and from the area including New Guinea, New Ireland and New Britain further east to the Pacific islands at the peripheries of the distribution range. The origin of the Fijian species dates back to the Pliocene.Main conclusions Dispersal over oceanic water barriers has occurred during geological time and seems to have been a major driving force for divergence events in Aglaieae, with some old Gondwanan land masses (e.g. Australia) colonized only during recent times. Movement from the ancestral area was predominantly towards the east. Extant Fijian species of Aglaia are monophyletic and share morphological features rarely found in species of other areas, suggesting speciation within an endemic clade. Divergence of living taxa from their closest living relatives took place during both the Miocene and the Pliocene, and peaked in the Pliocene. The present-day distribution of many species in the tribe must therefore have arisen as a result

Eight new compounds, including two cyclopenta[b]benzopyran derivatives (1, 2), two cyclopenta[b]benzofuran derivatives (3, 4), three cycloartane triterpenoids (5–7), and an apocarotenoid (8), together with 16 known compounds, were isolated from the chloroform-soluble partitions of separate methanol extracts of a combination of the fruits leaves and twigs, and of the roots of Aglaia perviridis collected in Vietnam. Isolation work was monitored using human colon cancer cells (HT-29) and facilitated with an LC/MS dereplication procedure. The structures of the new compounds (1–8) were determined on the basis of spectroscopic data interpretation. The Mosher ester method was employed to determine the absolute configurations of 5–7, and the absolute configurations of the 9,10-diol unit of compound 8 was established by a dimolybdenum tetraacetate [Mo2(AcO)4] induced circular dichroism (ICD) procedure. Seven known rocaglate derivatives (9–15) exhibited significant cytotoxicity against the HT-29 cell line, with rocaglaol (9) being the most potent (ED50 0.0007 µM). The new compounds 2–4 were also active against this cell line, with ED50 values ranging from 0.46 to 4.7 µM. The cytotoxic compounds were evaluated against a normal colon cell line, CCD-112CoN. In addition, the new compound perviridicin B (2), three known rocaglate derivatives (9, 11, 12), as well as a known sesquiterpene, 2-oxaisodauc-5-en-12-al (17), showed significant NF-κB (p65) inhibitory activity in an ELISA assay.

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