No abstract

Glaucumolides A (1) and B (2), novel biscembranes composed of an unprecedented α,β-unsaturated ε-lactone, along with the known metabolites ximaolide A (3) and isosarcophytonolide D (4), were isolated from the cultured soft coral Sarcophyton glaucum. The structures of the new metabolites were determined by extensive spectroscopic analyses. Compounds 1 and 2 were shown to exhibit cytotoxicity against a limited panel of cancer cell lines. In anti-inflammation assay, compounds 1 and 2 displayed strong inhibition of superoxide anion generation and elastase release in human neutrophils stimulated by fMLP/CB. Furthermore, both 1 and 2 were shown to significantly inhibit the accumulation of the pro-inflammatory inducible nitric oxide synthase protein, and compounds 1−3 were found to effectively reduce the expression of cyclooxygenase-2 protein, in lipopolysaccharide-stimulated RAW264.7 macrophage cells.

Antioxidant-directed fractionation of an ethyl acetate extract of Streptomyces sp. TC1 resulted in the isolation of a novel secondary metabolite with an aromatic organofluorine scaffold (1), an atypical tripod-type triallyl phenol (2), and a leucine residue comprised polyamine (3). Their structures were established by comprehensive spectroscopic analysis of 1D and 2D NMR data, and compound 1 was confirmed by (19)F NMR and single-crystal X-ray diffraction studies. The absolute configuration of compound 3 was assigned by comparison of its ECD spectra and quantum chemical ECD calculations. Of these, compound 1 displayed antioxidant and DNA and protein binding properties.

Four new isoprenoids, including two norcembranoids sinulerectols A and B (1 and 2), a cembranoid sinulerectol C (3), and a degraded cembranoid sinulerectadione (4), along with three known isoprenoids, an unnamed norcembrene (5), sinularectin (6), and ineleganolide (7), and a known nitrogen-containing compound (Z)-N-[2-(4-hydroxyphenyl)ethyl]-3-methyldodec-2-enamide (8), were isolated from an extract of the marine soft coral Sinularia erecta. The structure of sinularectin (6) was revised, too. Compounds 3, 4, and 8 exhibited inhibitory activity against the proliferation of a limited panel of cancer cell lines, whereas 1, 2, and 8 displayed potent anti-inflammatory activity in fMLP/CB-stimulated human neutrophils.