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Monitoring ATP cleavage by fluorescence

14 Nov 2013

Exploring enzymatic systems that use adenosine triphosphate (ATP) can improve our understanding of various biological pathways. The production of ATP cleavage products can be monitored in vitro using radioactive ATP analogues or by the colorimetric detection of released phosphate or pyrophosphate. These methods do not allow the continuous detection of ATP turnover. Enzyme-coupled assays offer an alternative means to explore these systems, but require consideration of the effects of additional enzymes. Thus, there is a need for probes that enable the continuous study of enzymatic ATP consumption.

This HOT article describes the synthesis of ATP analogues labelled with a fluorescence donor and a fluorescence acceptor, suitable for Förster Resonance Energy Transfer. Excitation promotes energy transfer from the fluorescence donor to the fluorescence acceptor on the same molecule. Cleavage of the ATP analogue prevents energy transfer via an intramolecular pathway, resulting in a large change in fluorescence. Synthetic routes to seven new doubly labelled ATP analogues are reported and the fluorescence properties of these molecules are described using snake venom phosphodiesterase as a model enzyme.

Synthesis and fluorescence characteristics of ATP-based FRET probes
Norman Hardt, Stephan M. Hacker and Andreas Marx
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41751D

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Professor Ramachary joins the Advisory Board

05 Nov 2013

We are pleased to announce that Professor Dhevalapally B. Ramachary, University of Hyderabad, has recently joined the Organic & Biomolecular Chemistry Advisory Board.

The main focus of his research group is to engineer novel and green asymmetric cascade and multi-component reactions (MCRs) to generate biologically important molecules and natural products in a single step via emerging chiral amines or amino acid-catalysis.

His research group is actively engaged in the design and synthesis of novel enzyme mimetic small organic amines and amino acids to catalyze the fundamental organic reactions in an enantioselective manner.

Direct organocatalytic stereoselective transfer hydrogenation of conjugated olefins of steroids
RSC Adv., 2013,3, 13497-13506 DOI: 10.1039/C3RA41519H, Paper

Direct catalytic asymmetric synthesis of highly functionalized (2-ethynylphenyl)alcohols via Barbas–List aldol reaction: scope and synthetic applications
Org. Biomol. Chem., 2012, 10, 5094-5101 DOI: 10.1039/C2OB25563D, Paper

Observation of neighboring ortho-hydroxyl group participation in organocatalytic asymmetric sequential Michael-lactonization reactions: synthesis of highly substituted chiral spirodihydrocoumarins
Org. Biomol. Chem., 2012, 10, 5825-5829 DOI: 10.1039/C2OB07122C, Communication

Discovery of 2-aminobuta-1,3-enynes in asymmetric organocascade catalysis: construction of drug-like spirocyclic cyclohexanes having five to six contiguous stereocenters
Chem. Commun., 2012,48, 2252-2254 DOI: 10.1039/C2CC17219D, Communication

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Oliver Kappe: Freedom to explore

24 Oct 2013

Oliver Kappe is professor of chemistry at the University of Graz in Austria. Research in the Kappe group focuses on enabling technologies for synthesis, including microwave and continuous flow methods.

Read some of his recent work in OBC and Green Chemistry:

A three step continuous flow synthesis of the biaryl unit of the HIV protease inhibitor Atazanavir

Design and evaluation of improved magnetic stir bars for single-mode microwave reactors

On the mechanism of the Dakin–West reaction

Nanocatalysis in continuous flow: supported iron oxide nanoparticles for the heterogeneous aerobic oxidation of benzyl alcohol

Direct aerobic oxidation of 2-benzylpyridines in a gas–liquid continuous-flow regime using propylene carbonate as a solvent

Can you tell us what inspired you to become a scientist?

In my case it was pretty straightforward since my father was also a professor of organic chemistry at the University of Graz. It’s a family affair!

What led you towards microwave chemistry in particular?

At a conference in 1998 in Hungary I heard a lecture by Professor Rajender Varma, now at the US EPA, highlighting the benefits of doing organic chemistry under microwave conditions. At that time it was all kitchen microwaves, there was almost nothing else available. That same year we started our collaboration and the following year published our first joint paper together.

I liked it so much that we continued in many different areas. We studied fundamental issues, such as the occurrence of special microwave effects, as well as the application of microwave chemistry in organic synthesis and fields like peptide chemistry, nanomaterials, polymer synthesis. And of course, finally, we looked at how to scale-up microwave chemistry.

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HOT Organic & Biomolecular Chemistry articles for October

22 Oct 2013

The development of highly active acyclic chiral hydrazides for asymmetric iminium ion organocatalysis
Eoin Gould, Tomas Lebl, Alexandra M. Z. Slawin, Mark Reid, Tony Davies and Andrew D. Smith
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41719K, Paper

Free to access until 2nd December

Efficient and regioselective nickel-catalyzed [2 + 2 + 2] cyclotrimerization of ynoates and related alkynes
Sanjeewa K. Rodrigo, Israel V. Powell, Michael G. Coleman, Jeanette A. Krause and Hairong Guan
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41872C, Communication

Free to access until 25th November

Characterization of CYP76AH4 clarifies phenolic diterpenoid biosynthesis in the Lamiaceae
Jiachen Zi and Reuben J. Peters
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41885E, Communication

Free to access until 25th November

The Cope rearrangement of gem-dimethyl substituted divinylcyclopropanes
Jonathan D. Osler, William P. Unsworth and Richard J. K. Taylor
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41617H, Paper

Free to access until 18th November

Expand this blog to see more Hot articles

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Gold nanoparticles detect avian influenza

07 Oct 2013

The influenza virus is capable of crossing from animals to humans. The health threat posed by influenza jumping the species barrier has been highlighted by recent outbreaks: N5N1 ‘bird flu’ in 2003/2004, H1N1 ‘swine flu’ in 2009 and avian H7N9 earlier this year. Current methods used for the detection of influenza are time consuming and may require trained analysts and specialised equipment. There is a need for a rapid diagnostic test to discriminate between human influenza and emerging animal strains.

This HOT article describes a gold nanoparticle-based colorimetric assay for the detection of influenza. Specificity was achieved by targeting the haemagglutanin (HA) surface glycoprotein. Human influenza binds preferentially to sialic acid α2,6 galactose sequences and avian influenza preferentially binds to sialic acid α2,3 galactose sequences. Gold nanoparticles were functionalised with trivalent α2,6-thio-linked sialic acid ligands and polyethylene glycol ligands. A solution of gold nanoparticles was used to detect HA virus surface glycoproteins and in the presence of human influenza virus a colour change was observed. The colour change was caused by the aggregation of the glycopeptide with the influenza virus and was detectable with the naked eye. Owing to the careful choice of ligands, this assay was able to discriminate between human and avian H5N1 influenza.

Glyconanoparticles for the plasmonic detection and discrimination between human and avian influenza virus
María J. Marín, Abdul Rashid, Martin Rejzek, Shirley A. Fairhurst, Stephen A. Wharton, Stephen R. Martin, John W. McCauley, Thomas Wileman, Robert A. Field and David A. Russell
Org. Biomol. Chem., 2013,11, 7101-7107
DOI: 10.1039/C3OB41703D

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OMCOS 17 poster prizes

26 Sep 2013

Congratulations to Carla Obradors and Keisuke Nakamura who received poster prizes from OBC and Chemical Science at OMCOS 17 (17th IUPAC International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis).

Carla Obradors, from the group of Professor Antonio Echavarren at Institute of Chemical Research of Catalonia (ICIQ) won for a poster entitled “Role of the Counterion in Intermolecular Gold(I)-Catalyzed Cycloadditions“, while Keisuke Nakamura from the group of Professor Naoto Chatani at Osaka University presented a poster entitled “Nickel-Catalyzed Transformations Involving the Cleavage of a Carbon-Nitrogen Bond in Aniline Derivative“.

Both winners received a copy of Organometallic Chemistry, edited by Ian J S Fairlamb, Jason M Lynam. Their awards were presented by Chemical Science Associate Editor Matt Gaunt.

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RSC Organic Division Poster Symposium – Deadline for poster abstracts 02 October 2013

23 Sep 2013

RSC Organic Division Poster Symposium: Deadline for poster abstracts 02 October 2013

The RSC Organic Division Poster Symposium is still accepting abstracts, but not for long. If you are a final year PhD student based in the UK/ROI and would like the opportunity to showcase your work to leading chemists in industry and academia, as well as your peers, make sure you submit your poster abstract by Wednesday 2^nd October.

The symposium will take place on Monday 2^nd December 2013, at The Chemistry Centre, Burlington House, London and there are several prizes available on the day. Alongside the £500 First Prize, there will also be a £500 “Selected by Industry” prize and two runners-up prizes of £250. And this year our headline sponsor, F. Hoffmann-La Roche are offering a further prize of a visit to their site in Basel, Switzerland, to the First and Industry prize winners.

Reasonable travel costs will be covered for the students who are selected to present at this meeting. If you would like to find out more about the symposium and submit an abstract, visit our symposium website

We would like to thank F. Hoffmann-La Roche, Ltd. for their generous support of this event.

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HOT Organic & Biomolecular Chemistry articles for September

19 Sep 2013

Disulfide bond reduction-triggered molecular hydrogels of folic acid–Taxol conjugates
Chengbiao Yang, Dongxia Li, Qianqi FengZhao, Lianyong Wang, Ling Wang and Zhimou Yang
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB40969D, Paper

The influence of G-quadruplex structure on DNA-based asymmetric catalysis using the G-quadruplex-bound cationic porphyrin TMPyP4·Cu
Michael Wilking and Ulrich Hennecke
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41366G, Paper

A highly active cyclometallated iridium catalyst for the hydrogenation of imines
Barbara Villa-Marcos, Weijun Tang, Xiaofeng Wu and Jianliang Xiao
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41150H, Paper

ω-Transaminase-catalyzed asymmetric synthesis of unnatural amino acids using isopropylamine as an amino donor
Eul-Soo Park, Joo-Young Dong and Jong-Shik Shin
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB40495A, Paper

Visible-light activatable organic CO-releasing molecules (PhotoCORMs) that simultaneously generate fluorophores
Ping Peng, Chaoming Wang, Zheng Shi, Valentine K. Johns, Liyuan Ma, Jeremiah Oyer, Alicja Copik, Robert Igarashi and Yi Liao
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41385C, Communication

The first asymmetric total synthesis of (+)-coriandrone A and B
Wenjing Wang, Jijun Xue, Tian Tian, Yingdong Jiao and Ying Li
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41497C, Communication

Convergent synthesis and cellular uptake of multivalent cell penetrating peptides derived from Tat, Antp, pVEC, TP10 and SAP
Gabriela A. Eggimann, Stefanie Buschor, Tamis Darbre and Jean-Louis Reymond
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41023D, Paper

Copper(II) chloride mediated (aza)oxindole synthesis by oxidative coupling of C_sp²–H and C_sp³–H centers: substrate scope and DFT study
Chandan Dey, Evgeny Larionov and E. Peter Kündig
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41254G, Paper

Histidine-functionalized water-soluble nanoparticles for biomimetic nucleophilic/general-base catalysis under acidic conditions
Geetika Chadha and Yan Zhao
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41485J, Paper

A one-pot coupling–addition–cyclocondensation sequence (CACS) to 2-substituted 3-acylpyrroles initiated by a copper-free alkynylation
Jan Nordmann and Thomas J. J. Müller
Org. Biomol. Chem., 2013, DOI: 10.1039/C3OB41269E, Paper

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Chemical and Biological Therapeutic Approaches to Neurological Disorders II

16 Sep 2013

There’s still time to register for the second one-day symposium on Chemical and Biological Therapeutic Approaches to Neurological Disorders, on Monday 23^rd September. The meeting will feature presentations and posters, from leading experts in academia and industry, about new developments in genetics, biochemistry, pathophysiology and medicinal chemistry relating to neurological disorders. A wide range of conditions will be discussed, including Alzheimer’s disease, epilepsy, schizophrenia, multiple sclerosis and Parkinson’s disease.

Neurological disorders are an increasingly important global public health problem, and the cause of much long-term suffering and disability. Currently available pharmaceuticals have been ineffective in curing many of these disorders and developing a deeper understanding of the nervous system is one of the major challenges facing scientists in the 21^st century. New research will hopefully contribute to the identification of better clinical biomarkers and medicines for diagnosis, monitoring and treatment of neurological disorders.

This one day symposium has been organised by the RSC’s Biotechnology Group with support from the Chemistry Biology Interface Division, and will be held at The Chemistry Centre, Burlington House, London. Speakers include:

Prof. Christopher Dobson, University of Cambridge
Prof. Ciaran Regan, University College Dublin
Prof. Lennart Bunch, University of Copenhagen
Prof. Peter Jenner, King’s College London
Prof. Stefan Przyborski, University of Durham
Dr. Jan Kehler, H. Lundbeck, A/S
Prof. Jonathan Corcoran, University College Dublin
Dr. Jan Passchier, Imanova Ltd.

If you would like to attend, please register here.

If you would like to find out more about this event, more information can be found on the RSC website.

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HOT – A new approach to inhibit human β-tryptase

12 Feb 2013

In this HOT article Carsten Schmuck and co-workers report the synthesis and evaluation of a series of four-armed peptide ligands that can inhibit β-tryptase. These tetravalent ligands are made up of 2 sets of arms incorporating the artificial arginine analogue guanidiniocarbonyl pyrrole cation and can inhibit β-tryptase in a reversible and non-competitive way by binding to anionic hotspots on the surface of the enzyme.

Read the complete study for free for 4 weeks!

A new approach to inhibit human β-tryptase by protein surface binding of four-armed peptide ligands with two different sets of arms
Qian-Qian Jiang, Lina Bartsch, Wilhelm Sicking, Peter R. Wich, Dominik Heider, Daniel Hoffmann and Carsten Schmuck
DOI: 10.1039/C3OB27302D

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