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Abstract: A new oxazole (1) was obtained from Chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2–4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro. [Copyright &y& Elsevier]

Six new polyketides, alternaritins A–D [(±)- 1 – 4 ] and isoxanalteric acid I (8), and 25 known Alternaria toxins were isolated from the culture of an endophytic fungi Alternaria sp. MG1. 3 is a rare fungal metabolite. 6 is a new natural product, and 5 , 7 , and 9 are known previously but their absolute configurations have not been determined. Three enantiomers [(±)- 1 , (±)- 7 , and (±)- 15 ] were separated via chiral HPLC resolution. The structures of those polyketides (1 – 9) were elucidated by spectrometric analysis using MS and NMR. The absolute configurations were established using X-ray diffraction analysis and statistical comparative analysis of the experimental ECD and OR data, in conjunction with quantum mechanical calculations. All of the compounds were evaluated for their bioactivities. Known compound 27 exerted the most potent cytotoxic activities against HT-1080 and NCI-H1299 cell lines. The new compounds, 2 and 3 , showed moderate inhibition on COX-2, while a pair of isomers, 8 and 9 , exhibited medium activity on COX-2 and uropathogenic Escherichia coli. [Display omitted] [ABSTRACT FROM AUTHOR]

Bidens pilosa is used in various folk medicines such as antimalarial, antibacterial, blood pressure-lowering, and antihyperglycemic agents. Phytochemical investigation of the aerial parts of this plant yielded 10 polyacetylenes and 9 flavonoids, including four new polyacetylenes (5, 7- 9) and one new chalcone glucoside (11). The molecular structures of the isolated compounds were elucidated by comprehensive spectroscopic analysis., (Georg Thieme Verlag KG Stuttgart-New York.)

Two new 8,9-seco-cacalol-type sesquiterpene lactones, ligulolide C (1 and 2) and six known sesquiterpenes, adenostylide (3 and 4), cacalol (5), 1 -hydroxy-2-(3'-pentenyl)-3,7-dimethylbenzofuran (6), 1beta, 6alpha-dihydroxy-4(14)-eudesmene (7) and (+)-oplopanone (8), have been isolated from an extract of the whole plant of Ligularia virgaurea spp. oligocephala. The structures of 1 and 2 were confirmed by spectroscopic methods including 1D and 2D NMR spectra. A discussion of biogenesis of 1 and 2 was described. Cytotoxicity against selected cancer cells human promyelocytic leukemia (HL-60), human ovarian (HO-8910) and human lung epithehial (A-549) of compounds 1-8 were measured in vitro.

[structure: see text] [structure: see text] Sesquiterpene lactones, ligulolide A (1) and 6beta,8alpha-dihydroxy-1-oxoeremophila-7(11),9(10)-diene-12,8-olide (2), were isolated from Ligularia virgaurea spp. oligocephala. Their structures were established by analysis of one- and two-dimensional NMR data. The relative stereostructures were determined on the basis of NOESY and single-crystal X-ray experiments. 1 represents a novel sesquiterpene carbon framework, and a possible biosynthetic process is proposed. 2 is a novel eremophilane-type sesquiterpene.