Contemporary 14C radiocarbon levels of oxygenated polybrominated diphenyl ethers (O-PBDEs) isolated in sponge–cyanobacteria associations

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Pollution Bulletin 62 (2011): 631-636, doi:10.1016/j.marpolbul.2010.12.022.Considerable debate surrounds the sources of oxygenated polybrominated diphenyl ethers (O-PBDEs) in wildlife as to whether they are naturally produced or result from anthropogenic industrial activities. Natural radiocarbon (14C) abundance has proven to be a powerful tool to address this problem as recently biosynthesized compounds contain contemporary (i.e. modern) amounts of atmospheric radiocarbon; whereas industrial chemicals, mostly produced from fossil fuels, contain no detectable 14C. However, few compounds isolated from organisms have been analyzed for their radiocarbon content. To provide a baseline, we analyzed the 14C content of four OPBDEs. These compounds, 6-OH-BDE47, 2’-OH-BDE68, 2’,6-diOH-BDE159, and a recently identified compound, 2’-MeO-6-OH-BDE120, were isolated from the tropical marine sponges Dysidea granulosa and Lendenfeldia dendyi. The modern radiocarbon content of their chemical structures (i.e. diphenyl ethers, C12H22O) indicates that they are naturally produced. This adds to a growing baseline on, at least, the sources of these unusual compounds.The project described was supported in part by Grant Numbers NA16RU1496 and NA06OAR4300227 from the National Oceanic and Atmospheric Administration, and Grant Number 5P20RR021929 from the National Center for Research Resources

Cyclocarbonylative Sonogashira Reactions of 1-Ethynylbenzyl Alcohols: Synthesis of 1-Carbonylmethylene-1,3-Dihydroisobenzofurans

In this work, we present a carbonylative Sonogashira reaction of o-ethynyl benzyl alcohols and aryl iodides, followed by a cyclization process to selectively give carbonylmethylene isobenzofurans in high yields and in an atom-economic fashion. The reaction can be carried out in the absence of CuI, with a small amount of PdCl2(PPh3)2 (0.2–0.5 mol-%), using aryl iodides bearing both electron-withdrawing and electron-donating groups. Of the two possible stereoisomeric products, Z-isobenzofuran derivatives were obtained as major products. But, when the reaction was extended to a secondary alcohol, an interesting switch in stereoselectivity was observed

Chlorinated Didemnins from the Tunicate Trididemnum solidum

Chemical investigation of the tunicate Trididemnum solidum resulted in the isolation of two new chlorinated compounds belonging to the didemnin class, along with two known compounds didemnin A and didemnin B. The structural determination of the compounds was based on extensive NMR and mass spectroscopic analysis. The isolated compounds 1–4 were tested for their anti-inflammatory activity using in vitro assays for inhibition of inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB) activity. The anti-cell proliferative activity of the above compounds was also evaluated against four solid tumor cell lines

Antibacterial Secondary Metabolites from the Cave Sponge <em>Xestospongia </em>sp.

Chemical investigation of the cave sponge <em>Xestospongia </em>sp. resulted in the isolation of three new<strong> </strong>polyacetylenic long chain compounds along with two known metabolites. The structures of the new metabolites were established by NMR and MS analyses. The antibacterial activity of the new metabolites was also evaluated

Appendix B. Statistical analyses of soft-coral genets.

Statistical analyses of soft-coral genets