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Three new dammarane-type triterpenoids, namely elliptaglin A-C ( 1 - 3 ) were isolated from the stem bark of Aglaia elliptica (C.DC.) Blume along with three known derivatives, namely (20 S )-hydroxydammar-24-en-3-on ( 4 ), cabralealactone ( 5 ), and E -25-hydroperoxydammar-23-en-20-ol-3-one ( 6 ). Subsequently, their chemical structures were determined using HR-ESI-MS, FTIR, 1D and 2D-NMR spectroscopic analysis as well as comparison with previous studies. The cytotoxicity activities of the isolated compounds against MCF-7 breast cancer and B16-F10 melanoma cell lines were then tested using PrestoBlue reagent. The analysis results showed that elliptaglin B ( 2 ) had the strongest activity against both cell lines with IC 50 values of 60.98 and 51.83 µM, respectively.

A novel 2,3-epoxy naphthoquinol, named (6 R ,7 R ,8 R )-theissenone A ( 1 ), possessing an oxatricyclo[5.4.0.0 3,5 ]undeca-trien-2-one skeleton, together with two known compounds, (6 S ,7 R ,8 R )-theissenone ( 2 ) and arthrinone ( 3 ), were produced by an endophytic fungus, Arthrinium marii M-211, which was isolated from mangrove plants. The structure of 1 , including the absolute stereochemistry, was elucidated by analysis of nuclear magnetic resonance (NMR) and mass spectrometry (MS) data and time-dependent density functional theory (TDDFT) calculations of electronic circular dichroism (ECD) spectra. Additionally, the absolute structure of 2 was deduced as a diastereomer of 1 using ECD spectral data analysis. Compounds 1 , 2 and 3 exhibited cytotoxic activity against the H4IIE rat hepatoma cells, with IC 50 values of 67.5, 46.6 and 13.4 µM, respectively.

Two new compounds, a new lactone, quercilactone A ( 1 ), and (17 R )-hydroxynafuredin ( 5 ), as well as five known compounds, scytalone ( 2 ), 3 S ,4 R -hydoxy-scytalone ( 3 ), nafuredin ( 4 ), (+)-(3 R ,5 R )-3-hydroxy-5-decanolide ( 6 ) and 3-ethyl-4-hydroxy-6-methyl-2 H -pyran-2-one ( 7 ), were isolated from Raffaelea quercivora , a fungus that causes Japanese oak wilt disease. The structures of these compounds were determined by 1D and 2D NMR spectroscopic analyses. The absolute configuration at C-17 of 5 was determined to be R by the modified Mosher's method. Compounds 1 , 2 , and 7 exhibited weak phytotoxic activity in lettuce seedlings at a concentration of 100 μg mL -1 .

Two new naphthoquinone derivatives, 6-hydroxy-astropaquinone B ( 1 ) and astropaquinone D ( 2 ) as well as the known compound 3- O -methyl-9- O -methylfusarubin ( 3 ) were isolated from Fusarium napiforme , an endophytic fungus isolated from the mangrove plant, Rhizophora mucronata . The structures of 1 and 2 were determined by 1D and 2D NMR spectroscopic analyses. Compounds 1 , 2 and 3 exhibited moderate antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa . Furthermore, 1 , 2 and 3 were phytotoxic action in lettuce seeding at a concentration of 30 μg · mL -1 .

The endophytic fungus, Clonostachys rosea B5-2 was isolated from mangrove plants and subjected to the one strain many compounds (OSMAC) methodology. By this approach, it was found that modification of the culture media enhanced the production of secondary metabolites by C. rosea B5-2. The apple juice supplemented solid rice media led to significant changes in the secondary metabolism of the fungus, C. rosea B5-2, and induced the production of four new compounds, (-)-dihydrovertinolide ( 2 ), and clonostach acids A ( 3 ), B ( 4 ), and C ( 5 ) together with the known compound, (-)-vertinolide ( 1 ). The new compound (-)-dihydrovertinolide ( 2 ) exhibited phytotoxicity against lettuce seedlings at a concentration of 50 mg L -1 .

A new limonoid, pentandricine (1), along with three known limonoids, ceramicine B (2), 6-de(acetyloxy)-23-oxochisocheton (3), 6-de(acetyloxy)-23-oxo-7-O-deacetylchisocheton (4), have been isolated from the stembark of Chisocheton pentandrus. The chemical structures of the new compound were elucidated on the basis of spectroscopic evidence. All of the compounds were tested for their cytotoxic effects against MCF-7 breast cancer cells. Compounds 1-4 showed weak and no cytotoxicity against MCF-7 breast cancer cells with IC 50 values of 369.84, 150.86, 208.93 and 120.09 μM, respectively.

New (-)-5',6-dimethoxyisolariciresinol-(3″,4″-dimethoxy)-3α-O-β-d-glucopyranoside compound was isolated from the methanol extract of the bark of Aglaia eximia (Meliaceae). The chemical structure of the new compound were elucidated on the basis of spectroscopic data including, UV, IR, HR-ESI-TOFMS, 1D-NMR, 2D-NMR and comparison with those related compounds previously reported.