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Two new eudesmanolides, 3β-acetoxy-1β,4α-dihydroxy-11αH-eudesman-12,6α-olide (1) and 3β-acetoxy-1β-hydroxy-11αH-eudesman-4(15)-en-12,6α-olide (2), were isolated from the flowers of Achillea millefolium, their structures were established on the basis of spectral analysis.

A rare new cyclic tetrapeptide, 5,5′-epoxy-MKN-349A (1), featured by a MKN-349A (5) skeleton and containing an uncommon ether bridge between C(5) and C(5′), and a new steroid, named 11-O-acetyl-NGA0187 (2), together with two known steroids, 3 and 4, were isolated from an endophytic fungus Penicillium sp. GD6 associated with the Chinese mangrove Bruguiera gymnorrhiza. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analyses and by comparison with the data of related compounds reported in literature. Neither of the compounds 3 and 4, isolated in this study, showed obvious bioactivities in the antibacterial bioassay experiments.

Five new limonoids, aphagranols D–H (1–5, resp.), were isolated from the EtOH extract of the fruits of Aphanamixis grandifolia by chromatographic methods. Their structures were established on the basis of extensive spectroscopic analyses. The absolute configuration of 1 was determined by comparison the experimental and calculated electronic circular dichroism (ECD) spectra. All of the isolates were evaluated for insecticidal activities.

Torreyanoxane, a novel 3,4-secoglutinane triterpenoid, was isolated from the pulp of Torreya nucifera. The structure was determined on the basis of spectroscopic methods.

Two new natural taxanes were isolated from the heartwood of Taxus cuspidata. The structures were established as rel-(2α,5α,7β,9α,10β,12α)-7,9-bis(acetyloxy)-2-(benzoyloxy)-11,12-epoxy-1,5-dihydroxy-10-[(hydroxyacetyl)oxy]tax-4(20)-en-13-one (1), and (2α,5α,10β,14β)-taxa-4(20),11-diene-2,5,10,14-tetrol 2-acetate (2) on the basis of spectroscopic analysis.

Two new meroterpenes, ‘acetoxydehydroaustin B’ (1) and ‘1,2-dihydro-acetoxydehydroaustin B’ (2) were isolated in the form of a mixed crystal from the mangrove endophytic fungus Aspergillus sp. 085241B. Their structures and absolute configurations were determined by extensive analysis of their spectra and X-ray diffraction data. In a preliminary bioassay, the mixed crystal did not exhibit activities against cancer cell lines of MDA-MB-435, SKBR3, HepG2, HEP3B, PC-3, and A549, as well as against α-glucosidase and tyrosinase.

A new lactone, 1,8-dihydroxy-10-methoxy-3-methyldibenzo[b,e]oxepine-6,11-dione (1), and two new xanthones, 1-hydroxy-8-(hydroxymethyl)-6-methoxy-3-methyl-9H-xanthen-9-one (2) and 1-hydroxy-8-(hydroxymethyl)-3-methoxy-6-methyl-9H-xanthen-9-one (3), were isolated from a mangrove endophytic fungus Phoma sp. SK3RW1M collected from the South China Sea. This is the first report on xanthone derivatives isolated as secondary metabolites from Phoma species. Their structures were elucidated by spectroscopic methods, mainly 1D- and 2D-NMR techniques, and the structure of compound 2 was confirmed by X-ray crystallography. Cytotoxicity assays showed that compounds 1–3 were inactive against KB and KBv200 cells.

Two new cembrane diterpenes, sinulaparvalides A and B (1 and 2, resp.), which contain an intriguing seven-membered lactone moiety, along with the four known related cembranoids 3-6, were isolated from the Hainan soft coral Sinularia parva. The structures of compounds I and 2 were established by spectroscopic methods, mainly on the basis of 2D-NMR techniques, and were confirmed by single-crystal X-ray diffraction analysis. The in vitro cytotoxic activities of these compounds were tested on human colon carcinoma (HCT-116), human promyelocytic leukemia (HL-60), and human lung carcinoma (A-549) tumor cell lines.

Two new ent-abietane diterpenoids, macrophynin E (1) and macrophynin F (2), and a known related ent-abietanoid (−)-lambertic acid (3), together with four known ent-kauranoids, were isolated from the roots and aerial parts of Isodon macrophylla, respectively. The structures of the new compounds were elucidated on the basis of spectroscopic-data analysis and chemical correlations.