A new stereoisomer Meso-araguspongine C together with nine reported macrocyclic bis-quinolizidine alkaloids araguspongines A, C, E, L, N-P, petrosin, and petrosin A were isolated from marine sponge Xestospongia muta. Stereochemistry of meso-araguspongine C (2) and araguspongines N-P (3-5) were established by their NMR data and conformational analyses. Both araguspongine C (1) and meso-araguspongine C (2) exhibited great cytotoxic activity towards HepG-2, HL-60, LU-1, MCF-7, and SK-Mel-2 human cancer cells (IC in the range of 0.43-1.02 μM). At a concentration of 20 μM, isolated compounds (1-10) also showed modest inhibitory effects (from 7.6 to 40.8%) on the NO production in LPS activated RAW264.7 macrophages.

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Four new cucurbitane- type triterpene glycosides, charantosides D-G (1–4) were isolated from a methanol extract of Momordica charantia fruits. The structures of these compounds were determined by chemical and spectroscopic methods to be (19 R)-5 β,19-epoxy-25-methoxycucurbita-6,23-diene-3 β,19-diol 3- O-β-D-glucopyranoside, (19 R)-5 β,19-epoxy-25-methoxycucurbita-6,23-diene-3 β,19-diol 3- O-β-D-allopyranoside, 7 β-methoxycucurbita-5,23 E,25-triene-3 β-ol 3- O-β-D-allopyranoside, and 3 β,7 β-dihydroxycucurbita-5,23 E,25-triene-19-al 3- O-β-D-allopyranoside.

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Three new acetylated terpenoids, rhabdaprovidines A-C (1-3), were isolated from the Vietnamese sponge Rhabdastrella providentiae. Their chemical structures were established by HR-ESI-MS, 1D and 2D-NMR experiments. These compounds share 6,6,5-tricyclic nucleus of isomalabaricane-type triterpene, the specific secondary constituents from Rhabdastrella species. Compounds 1-3 inhibited NO production in LPS stimulated BV2 cells with IC 50 values of 20.4 ± 1.5, 17.5 ± 0.9, and 46.8 ± 2.3 µM, respectively.

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Chemical investigation of a fermentation culture of the marine endophytic fungus Paraconiothyrium sp. VK‐13 resulted in the isolation of five compounds, including a new phenolic compound, 1‐(2,5‐dihydroxyphenyl)‐1‐oxobutan‐3‐yl acetate (1) and four known metabolites, 1‐(2,5‐dihydroxyphenyl)‐2‐buten‐1‐one (2), 3,7‐dimethyl‐1,8‐dihydroxy‐6‐methoxyisochroman (3), modiolides A (4) and B (5). Their chemical structures were identified based on 1D, 2D NMR, and MS spectroscopic analysis and comparison with the data reported previously in the literature. All the isolated compounds were reported for the first time from the genus Paraconiothyrium.