Organic & Biomolecular Chemistry Blog

While protein assemblies are key to biological processes, their mis-assembly often leads to altered functions such as those found in neurodegenerative diseases. Considerable efforts are ongoing towards the understanding of the assembly processes, either using native or artificial systems.

In this OBC Hot article, Mingming Ma and Dennis Bong at the Ohio State University (Columbus, USA) construct a protein-protein artificial interface and demonstrate that when functionalized with synthetic cyanuric acid and melamine, the streptavidin proteins are able to assemble selectively, based on reversible supramolecular recognition. Such synthetic modules could be used to direct the molecular interactions for the construction of novel biomaterials and functional molecular assemblies.

Interested in proteins, biomaterials or supramolecular chemistry? This OBC Communication is for you!

FREE to access for a period of 4 weeks.

Protein assembly directed by synthetic molecular recognition motifs
Mingming Ma and Dennis Bong
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05998J, Communication

Arindam Banerjee and collaborators at the Indian Institute of Chemical Biology and Indian Association for the Cultivation of Science in Jadavpur (India) demonstrate the spontaneous formation of hierarchical vesicle-in-vesicle systems from remarkably simple peptides.

These multivesicular structures are stable over a wide pH range (2 to 12) and can encapsulate anticancer drugs and fluorescent dyes, while the release is triggered by biocompatible Ca2+ ions. Combined with a negligible cytotoxicity, these peptide based functional vesicles hold future promise as biocompatible delivery vehicles.

This article has been selected as HOT and will be free to access for the next 4 weeks. Why not read it now!

Self-assembling dipeptide-based nontoxic vesicles as carriers for drugs and other biologically important molecules Jishu Naskar, Subhasish Roy, Anindita Joardar, Sumantra Das and Arindam Banerjee
Org. Biomol. Chem., 2011, 9, 6610-6615
DOI: 10.1039/C1OB05757J, Paper

Victor Pike and colleagues from the National Institute of Mental Health in Bethesda (Maryland, USA) have devised novel and efficient methods to readily access 18F-labelled mGluR5 PET radioligands that are useful for molecular imaging with positron emission tomography (PET).

While iodonium based compounds are considered promising for the preparation of PET radiotracers, very few examples of applications have been realised so far. Now, Pike and colleagues have designed appropriate diaryliodonium tosylates as precursors for introducing fluorine-18 into simple arenes to radiosynthesise standard PET radiotracers. These would otherwise be poorly accessible via traditional aromatic nucleophilic substitution reactions with the [18F]fluoride ion, due to the weak activation of the aryl ring.

The referees and the OBC Editorial office very much enjoyed this excellent paper, and we hope you will too! Read it for FREE for the next 4 weeks.

Syntheses of mGluR5 PET radioligands through the radiofluorination of diaryliodonium tosylates
Sanjay Telu, Joong-Hyun Chun, Fabrice G. Siméon, Shuiyu Lu and Victor W. Pike
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05555K, Paper

This hot article from Julio Casado and colleagues at the University of Salamanca provides the first study of the alkylating ability of p-nitrostyrene oxide (pNSO), which is widely used in the pharmaceutical industry as a chiral building block for a variety of drugs.  pNSO is also used as a substrate to study the activity of epoxide hydrolases and in polymer production.

4-(p-nitrobenzyl)pyridine (NBP), a model nucleophile for DNA bases, was used to study the alkylating effects of pNSO.  They found that although pNSO is a strong alkylating agent, it has low efficacy – probably due to the instability of the  NBP-pNSO adduct formed.  A previously unreported pNSO-guanosine adduct was also detected.

For the full details of this interesting study download the article – it’s currently free to access for 4 weeks:

Reactivity of p-nitrostyrene oxide as an alkylating agent. A kinetic approach to biomimetic conditions
Marina González-Pérez, Rafael Gómez-Bombarelli, M. Teresa Pérez-Prior, José A. Manso, Isaac F. Céspedes-Camacho, Emilio Calle and Julio Casado
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05909B

Ivan Jabin and collaborators in Belgium and France have designed a novel Calix[6]crypturea receptor with unique binding properties that are acid-base controllable.

This external stimulus is used to modulate the flexibility of the calixarene, allowing it to bind either neutral molecules, anions, primary/secondary ammonium ions, quaternary ammonium ions, with remarkable selectivity.

Interested? Why not read the article now and let us know what you think by leaving a comment below!

Acid–base modulation of a versatile heteroditopic calix[6]arene based receptor Damien Cornut, Jérôme Marrot, Johan Wouters and Ivan Jabin
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05759F, Paper

This OBC paper has been selected as a Hot Article and will be FREE to access to all for a period of 4 weeks.

While retinoids are essential in many biological processes such as vision or cell differentiation and can be found in many of our favorite cosmetic products, both phototoxicity and photocarcinogenicity have been reported for retinol. Professor Fukuzumi and Dr. El-Agamey at Ozaka University (Japan) are shedding light on the roles of retinol in phototoxicity and free radical initiated oxidative stress: using Laser Flash Photolysis, the scientists have successfully generated the retinol radical cation , which was found to be reactive towards bases and other carotinoids inducing pro-oxidant effects.

Wish to find out more? Why not read this OBC paper today!

Laser flash photolysis study on the retinol radical cation in polar solvents
Ali El-Agamey and Shunichi Fukuzumi
Org. Biomol. Chem.., 2011, Advance Article
DOI: 10.1039/C1OB05814B, Paper

This Hot Article will be FREE to access to all for a period of 4 weeks.

Haifeng Du and colleagues from the Chinese Academy of Sciences and the Beijing University of Chemical Technology (Beijing, PR China) have used a simple one-step condensation of a α,β-unsaturated ketones and readily available (R)-tert-butanesulfinamide to synthesise a variety of chiral olefin/sulfinimide hybrid ligands. Highly efficient in rhodium-catalyzed asymmetric 1,4-additions, these novel ligands lead to high yields with excellent ee’s (up to 98%) , and could find wide application as a useful asymmetric synthetic methodology.

Interested in asymmetric 1,4-additions? Why not read this OBC communication now!

Chiral N-tert-butanesulfinyl α,β-unsaturated ketimine: a simple and highly effective olefin/sulfinimide hybrid ligand for asymmetric 1,4-additions
Xiangqing Feng, Beibei Wei, Jing Yang and Haifeng Du
Org. Biomol. Chem., 2011, 9, 5927-5929
DOI: 10.1039/C1OB05971H

This OBC communication will be FREE to access to all for a period of 4 weeks