Three new scalarane-based sesterterpenes from the tropical marine sponge strepsichordaia lendenfeldi1

From the dichloromethane extract of the tropical marine sponge Strepsichordaia lendenfeldi collected from the Great Barrier Reef, Australia, three new (1, 2, and 9) and seven known (3-8 and 10) scalarane-based sesterterpenes were isolated. All molecular structures were secured by spectroscopic methods, particularly 1D and 2D NMR, and accurate mass measurement.

Halogenated monoterpenes from plocamium costatum and their biological activity1

From the dichloromethane solubles of the temperate red alga Plocamium costatum, one new [1,4-dibromo-2,3,6-trichloro-3, 7-dimethyl-7-octene] (1) and three previously reported polyhalogenated monoterpenes (2-4), and the known phytol derivative 3,7,11,15-tetramethylhexadec-1-en-3-ol (1-phyten-3-ol, 5) were isolated. The structure of 1 was deduced from its spectroscopic data. For compound 3, complete 1H and 13C NMR data are reported for the first time. The CH2Cl2 extract and compounds 3 and 5 deterred settlement of barnacle larvae, suggesting a potential ecological role of these isolates.

Three new metabolites from marine-derived fungi of the genera coniothyrium and microsphaeropsis

The marine sponges Ectyplasia perox and Myxilla incrustans were investigated for associated fungal strains. Among others, a Coniothyrium sp., from E. perox, and a Microsphaeropsis sp., from M. incrustans, were isolated, cultured, and investigated for their biologically active secondary metabolite contents. The new compound microsphaeropsisin (1) together with the known compounds (R)-mellein (4), (3R,4S)-hydroxymellein (5), (3R,4R)-hydroxymellein (6), and 4, 8-dihydroxy-3,4-dihydro-2H-naphthalen-1-one (7) were isolated from the Microsphaeropsis sp. From culture extracts of the Coniothyrium sp., the new compounds (3S)-(3',5'-dihydroxyphenyl)butan-2-one (2) and 2-(1'(E)-propenyl)-octa-4(E),6(Z)-diene-1,2-diol (3), together with the six known metabolites (3R)-6-methoxymellein (8), (3R)-6-methoxy-7-chloromellein (9), cryptosporiopsinol (10), phenylethanol, (p-hydroxyphenyl)ethanol, and 2-(hydroxymethyl)furan, were obtained. All structures were determined using spectroscopic methods. With the exception of 3, all compounds were tested for their antimicrobial properties, and all but 10 demonstrated significant antimicrobial activity in agar diffusion assays.

Geniculol, a new biologically active diterpene from the endophytic fungus geniculosporium sp.1

An endophytic fungus of the genus Geniculosporium was isolated from Teucrium scorodonia. The EtOAc extract of this isolate exhibited antialgal activities, as well as demonstrating an interesting profile during chemical screening. After mass cultivation of this fungus, in an optimized agar medium, two of the compounds responsible for the observed biological activity were isolated, the new diterpene geniculol (1), and the known fungal metabolite cytochalasin F (2). Geniculol is an unprecedented and irregular diterpenoid. For 1 and 2 complete 1H and 13C NMR data are reported. Both metabolites exhibit algacidal properties. Additionally, cytochalasin F was shown to be an inhibitor of photosynthesis, suggesting an ecological function in the plant-symbiont relationship for this secondary metabolite.