Archive for the ‘News’ Category

Polar solvents promote halogen bonds over hydrogen ones

Solvent effects control competition between hydrogen bonding and halogen bonding in supramolecular systems, new research shows. The upshot of the finding is a potential new tool to direct supramolecular self-assembly.

During self-assembly, each molecule breaks its bonding interactions with neighbouring solvent molecules, then forms new interactions. To investigate competition between hydrogen bonding and halogen bonding when co-crystals form, researchers from an ongoing collaboration between the UK Universities of Sheffield, York and Cambridge chose seven solvents of different polarities to study three aromatic molecules known to self-assemble. The molecules’ functional groups included pairs of hydrogen bond and halogen bond donors that compete for a common acceptor group.

Solvent plays a critical role in directing self-assembly

Read the full story by Fiona Tscherny on Chemistry World.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

First +5 praseodymium compound with PrN triple bond made

The first pentavalent praseodymium nitride–oxide that features a rare Pr≡N triple bond is the second ever lanthanide(V) complex to be made.

Lanthanide chemistry is dominated by the +3 oxidation state. There are some common +4 lanthanide complexes such as cerium oxide (CeO2), but +5 compounds have proven elusive. Praseodymium has long been considered as the most promising route to lanthanide(V) chemistry as it has five valence electrons, but the first pentavalent praseodymium complex, the oxide PrO2+, was only synthesised last year.

Source: © Royal Society of Chemistry
Calculations led to these representations of the molecular orbitals of the praseodymium(V) compound, NPrO

Read the full story by Aurora Walshe on Chemistry World.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

15-minute test catches out flu virus

A team in the US has designed a test for detecting influenza viruses in just 15 minutes using a glucose meter – a cheap, handheld instrument that is widely available.

Source: © Royal Society of Chemistry
Proteins sitting on the flu viruses’ surface cleave a carbon–oxygen bond in a modified sialic acid, releasing the sugar galactose

Suri S Iyer and colleagues from Georgia State University have now designed a test to detect influenza viruses A and B in just 15 minutes. The test only requires a nasal swab and a glucose meter – a simple instrument usually used for diabetes control. ‘Influenza virus can be deadly especially in weak or immunocompromised people. This diagnostic can help these people as vaccines for flu are not perfect,’ Iyer explains.

Read the full story by Adrian Robinson on Chemistry World.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Molecular suit provides basic protection

Scientists have designed a macrocycle that can completely surround a small molecule like a suit and protect it from a strong base. This reversible suiting strategy could find applications as protecting groups in organic synthesis and the design of molecular machines.


Source: © Royal Society of Chemistry
The suit-1-ane: a macrocycle (orange) completely encloses a benzimidazolium cation (blue)

Protecting groups alter the reactivity of organic molecules by shielding functional groups from other reactants. Mechanically interlocked molecules (MIMs) are linked structures that require a covalent bond to be broken to separate them, which could make them useful protecting groups.

Read the full story by Harriet Brewerton on Chemistry World.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Tamed radicals expand chemical space

A method to functionalise complex molecules with catalytic radicals could expand chemical libraries of the drug and agrochemical industry

Source: © Royal Society of Chemistry Even complex molecules like the anti-cancer drug camptothecin (top left) can be modified using Molander’s radical alkylation

US scientists have developed a visible-light mediated reaction that uses tamed alkyl radicals to functionalise complex molecules. This mild and selective method could allow chemists to explore new corners of chemical space and to discover new drugs and agrochemicals.

Read the full story by Jessica Dwyer on Chemistry World.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Neural network provides accurate simulations without the cost

An efficient new computer brain can provide quick answers to computational chemistry problems

A computer that has been taught about organic chemistry can describe the forces in molecules as accurately as density functional theory (DFT), but hundreds of thousands of times faster. This combination of speed and accuracy could allow researchers to tackle problems that were previously impossible.

Chemists hoping to use computer simulations face a dilemma. Researchers commonly need to know the energy of a molecule, and the forces that control how it twists and bends. Accurate methods like DFT, which use quantum mechanics, take the most computer power and time. Approximations such as semi-empirical methods give faster but less reliable results. Although there is a spectrum of options, most techniques ask researchers to trade off speed and accuracy.

Read the full story by Alexander Whiteside on Chemistry World.

 

 

Source: © Royal Society of Chemistry
The neural network can predict molecular energies hundreds of thousands of times faster than DFT

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Outstanding Reviewers for Chemical Science in 2016

Following the success of Peer Review Week in September 2016 (dedicated to reviewer recognition) during which we published a list of our top reviewers, we are delighted to announce that we will continue to recognise the contribution that our reviewers make to the journal by announcing our Outstanding Reviewers each year.

We would like to highlight the Outstanding Reviewers for Chemical Science in 2016, as selected by the editorial team, for their significant contribution to the journal. The reviewers have been chosen based on the number, timeliness and quality of the reports completed over the last 12 months.

We would like to say a big thank you to those individuals listed here as well as to all of the reviewers that have supported the journal. Each Outstanding Reviewer will receive a certificate to give recognition for their significant contribution.

Professor Atsushi Fukuoka, Hokkaido University

Dr Gilles Gasser, Chimie ParisTech, PSL Research University

Professor Dirk Guldi, Friedrich Alexander Universität

Dr Christian Hackenberger, Leibniz-Institut für Molekulare Pharmakologie im Forschungsverbund Berlin e.V. (FMP)

Dr Takashi Hisatomi, The University of Tokyo

Dr Paul Knochel, Ludwig-Maximilians-Universität

Professor Jun Kubota, Fukuoka University

Professor Stefan Matile, Universite de Geneve

Professor Frank Wuerthner, Universitaet Wuerzburg

Professor Juyoung Yoon, Ewha Womans University

We would also like to thank the Chemical Science board and the General Chemistry community for their continued support of the journal, as authors, reviewers and readers.

If you would like to become a reviewer for our journal, just email us with details of your research interests and an up-to-date CV or résumé. You can find more details in our author and reviewer resource centre

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

First observation of unusual hemi bond

Experimental evidence for two-centre three-electron bond described as ‘a triumph of spectroscopy’

Researchers in Japan have observed the stable hemi-bonded structure of (H2S)n+ (n = 3–6). Using infra-red (IR) spectroscopy, the team has experimental evidence for this unusual, previously only theoretically predicted, structure.

The two-centre three-electron (2c–3e) bond, also known as a hemi bond, was first proposed by Linus Pauling in the 1930s. It is formed by the lone pair orbitals of a neutral molecule and its radical cation overlapping, causing the bonding sigma orbital to be doubly occupied and the antibonding sigma* orbital to be singly occupied.

Read the full story by Suzanne Howson on Chemistry World.


Source: © Royal Society of Chemistry
Two possible structural motifs of (H2S)2+

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Stabilization of the world’s smallest lasso

Molecular snare threads through itself under redox conditions

Source: © Royal Society of Chemistry

The world’s smallest lasso has been created by scientists in Saudi Arabia and the US. The molecular device threads through itself, forming a reversible noose, in response to chemical and electronic stimuli.

The research team, led by 2016 Nobel prize-winner Fraser Stoddart of Northwestern University, were inspired by naturally occurring lasso peptides – molecules produced by a variety of bacteria, which consist of a linear peptide tail laced through a macrolactam ring.

Read the full story by Jamie Durrani on Chemistry World.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Meet Michelle Chang: Chemical Science Associate Editor

In August last year, we were delighted to welcome Professor Michelle Chang as Chemical Science Associate Editor, handling submissions in the area of chemical biology.

Michelle C. Chang earned a B.Sc. in Biochemistry and in French Literature at the University of California in San Diego. This was followed by research as a National Science Foundation Predoctoral Fellow and as a M.I.T./Merck Foundation Predoctoral Fellow. In 2004, she obtained her Ph.D. at the Massachusetts Institute of Technology with Professor JoAnne Stubbe and Professor Daniel G. Nocera.

After a Postdoctoral Fellowship at the University of California, Berkeley, she joined the faculty where she is currently working as an Associate Professor at the Department of Chemistry.

Michelle’s team uses the approaches of mechanistic biochemistry, molecular and cell biology, metabolic engineering, and synthetic biology to address problems in energy and human health. Her group designs and creates new biosynthetic pathways in microbial hosts for in vivo production of biofuels from abundant crop feedstocks and pharmaceuticals from natural products or natural product scaffolds.

Below is a list of hot Chemical Science articles published within Michelle’s area of expertise – all free to read. We hope you enjoy them!

Assembly Line Termination in Cylindrocyclophane Biosynthesis: Discovery of an Editing Type II Thioesterase Domain in a Type I Polyketide Synthase
H. Nakamura, J.X. Wang and E.P. Balskus
Chem. Sci., 2015,6, 3816-3822
DOI: 10.1039/C4SC03132F 

An enantioselective artificial Suzukiase based on the biotin–streptavidin technology
Anamitra Chatterjee, Hendrik Mallin, Juliane Klehr, Jaicy Vallapurackal, Aaron D. Finke, Laura Vera, May Marshb and Thomas R. Ward
Chem. Sci., 2016,7,673-677
DOI:  10.1039/C5SC03116H 

Next-generation disulfide stapling: reduction and functional re-bridging all in one
Maximillian T. W. Lee, Antoine Maruani, James R. Baker, Stephen Caddicka and Vijay Chudasama
Chem. Sci., 2016,7, 799-802
DOI: 10.1039/C5SC02666K

Activity modulation and allosteric control of a scaffolded DNAzyme using a dynamic DNA nanostructure
Xiuhai Mao, Anna J. Simon, Hao Pei, Jiye Shi, Jiang Li, Qing Huang, Kevin W. Plaxcob and Chunhai Fan
Chem. Sci., 2016,7, 1200-1204
DOI: 10.1039/C5SC03705K

You can submit your high quality research in the area of chemical biology to Michelle Chang’s Editorial Office.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)