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New eunicellin-base diterpenoids, klysimplexins I-T (1-12), were isolated from a cultured soft coral Klyxum simplex. Their structures were elucidated by spectroscopic methods, particularly in 1D and 2D NMR experiments. The absolute stereochemistry of 4 was determined by Mosher's method. Compounds 9 and 12 have been shown to exhibit cytotoxicity toward a limited panel of cancer cell lines. Compounds 2-6, 10 and 11 were found to display significant in vitro anti-inflammatory activity in LPS-stimulated RAW264.7 macrophage cells by inhibiting the expression of the iNOS protein. Compounds 10 and 11 also could effectively reduce the level of COX-2 protein.

Acute toxic responses as well as uptake and depuration rates for tributyltin (TBT) and dibutyltin (DBT) were examined in the small planktonic shrimp, Acetes intermedius. The 72-h LC(50) values of TBT and DBT for the shrimp were found to be 18.6 and 82.6 microg L(-1) as tin. The uptake rate constants of TBT and DBT in the shrimp were 0.0006 and 0.0002 L g(-1) h(-1), and the corresponding depuration rate constants were 0.0303 and 0.0106 h(-1), respectively. It appears that real-time ambient TBT pollution status can be more closely reflected in this species. The shrimp may serve as a biomonitor to indicate short-term fluctuations in ambient TBT pollution. A field survey was also conducted to distinguish contrasts in butyltin accumulation under different ambient conditions. These observations provide valuable information for the evaluation of TBT pollution status in the environment using A. intermedius as a biomonitor.