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Abstract: The cembranolides sartrolides A–G (1–7) and the dimer bissartrolide (8) were isolated from Sarcophyton trocheliophorum Marenzeller, along with three known analogues (9–11). Their stereochemistry was elucidated by spectroscopic analysis (IR, UV, NMR) and Flack single crystal X-ray diffraction analysis (for sarcrassin D and emblide), applied for the first time to this class of compounds. Sartrolides A–G (1–7) include an α,β-unsaturated ɛ-lactone and differ for the pattern of functionalization at C-1/C-8 moiety, including the rare 1Z,3E-diene system in sartrolide G. Bissartrolide (8) is only the third example of cembrane dimer found as a natural product. The known cembranolide 11 showed significant antibacterial activity against Staphylococcus aureus Newman strain. [Copyright &y& Elsevier]

Abstract: A detailed investigation of the South China Sea soft coral Sarcophyton trocheliophorum Marenzeller yielded, along with six known terpenes (6−11), the new sarcophytonolides N−R (1−5), whose structures have been elucidated by detailed spectroscopic analysis. Sarcophytonolides N–R are mono- or bicyclic cembranoids characterized by the presence of three/four double bonds and oxidized methyl groups. Some of the isolated compounds showed significant inhibitory activity against human protein tyrosine phosphatase 1B (PTP1B) enzyme, a key target for the treatment of type-II diabetes and obesity, and some preliminary structure–activity relationships have been drawn. This is the first report on the anti-PTP1B activity of cembrane diterpenoids. [Copyright &y& Elsevier]

In order to explore the interaction between the sea and monsoon in the South China Sea, the heat exchanges at air-sea interface during monsoon periods in 1986 were calculated using observational data. It shows that when the summer monsoon bursts and prevails over the South China Sea, the air-sea interface heat exchange is strong and the latent heat rises rapidly in the intertropical convergence zone and the tropic cyclone system near 20.49°N, 114.14°E. On May 24, 1986, the sensible heat became positive in the typhoon system. The heating exchange indicates that heat is transported from ocean to atmosphere, with major contribution of latent heat. When the summer monsoon prevails over the South China Sea and the weather is fine, even SST (sea surface temperature) is high, but sensible heat appears to be negative. The heat exchange indicates that heat is transported from atmosphere to ocean, with major contribution of short-wave radiation absorbed by sea surface and sensible heat. When summer monsoon is over and the northeast monsoon prevails over the South China Sea, the heat exchange at air-sea interface is very strong. The heating exchange shows that the ocean heats the atmosphere, with major contribution of latent heat when cold air arrives at the sea surface and the sensible heat rises to positive rapidly. Therefore it can be concluded that the heat exchange at air-sea interface is different from the SST in South China Sea. When the summer monsoon prevails over the South China Sea, the main trend is the ocean responding to the atmosphere. [ABSTRACT FROM AUTHOR]

Two new cembranoids, yalongenes A ( 1) and B ( 2), were isolated from the South China Sea soft coral Sarcophyton trocheliophorum Marenzeller. Their structures were elucidated by detailed spectroscopic analysis (IR, MS, and NMR) and by comparison with a related model compound. Yalongenes 1 and 2 were evaluated for their cytoprotective effects on SH-SY5Y cell injury induced by H2O2 in vitro, and the result showed that only compound 1 had a significant cytoprotective activity at the concentration of 1 μ M. [ABSTRACT FROM AUTHOR]