Spinneret - Weaving the chemical web one molecule at a time...

A newly discovered diterpene quesnoin with a novel ring structure, bridged by a single oxygen atom, has been isolated from 55 million-year-old amber from the Eocene geological period by Akino Jossang and colleagues at the National Museum of Natural History in Paris.

According to a report in Chemistry World, Jossang said that, “It is very difficult to isolate pure known compounds in amber, so to discover a new structure was unexpected and exceptional.” The biosynthesis is intriguing but whether or not the quesnoin has any potential applications is a different matter.

The compound is related to one from a tree found today only in the Amazon rainforest adding to the weight of evidence that Paris was once a tropical region. Anyone who has spent an August there will know how that might have been.

Spinneret host Tony Williams tells me that he used the new ChemSpider manual deposition scheme to add this new compound to the database. “We are about to rollout the ability for anyone to deposit structures on ChemSpider. This one took me 5 mins…about 3.5 of that drawing the structure!” The entry description includes the DOI of the original paper and links directly to it.

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This week’s Spinneret post actually points you to my latest Alchemist column on ChemWeb.com but also goes into a little more detail on one of the items reported there regarding pesticide contamination.

First off, Environmental research gets a boost from NIH in the form of a $6.8million grant to establish three DISCOVER centers to study the effects of environmental pollutants. Crystallography reveals the cellular machinations of the humble hydrogen peroxide molecule in The Alchemist this week, while fatty samples suggest that all of us harbor at least one pesticide or other persistent organic compound in our tissues. In environmental news, researchers have turned to gold to help them convert biomass into a useful chemical feedstock, while in theoretical studies it still matters, relatively, that electrons and nuclei are massively and speedily different. Finally, crystals behaving badly in supramolecular chemistry could herald new approaches to technological problems.

Read current issue of The Alchemist here.

Anyway, back to the contentious item on global contamination, which referred to news that almost everyone in Spain, and putatively the world, may be contaminated with at least one pesticide. I did have some misgivings about reporting on this and my concerns were brought into sharp relief by an Alchemist reader friend who happens to be a retired organic chemist with a great deal of experience.

He points out that the item on finding persistent organics in blood serum should really be put into perspective. “The fact that many of these studies find mainly halogenated compounds may well simply reflect the exquisite sensitivity of the detectors used in capillary gas chromatography to halogen,” he says, “these devices will pick up nanomolar concentrations of compounds containing chlorine or bromine.” He also asks whether strict controls were used by the investigators in this research and points out that work in this area submitted for regulatory filing requires stringent controls beyond simply showing a peak that has roughly the same Rf as a suspected pollutant.

More to the point, however, he questions the significance of finding traces of DDT or even DDE in serum. “If this were truly perilous the landscape should be littered with victims,” he says.

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