Thanks to developments in new phosphine ligands the area of C–Cl bond activation has made a lot of progress.
Do you think that this protocol is a versatile method for the organic community to utilise? Read the paper today and let us know by leaving your comments on this blog.
Pd-catalyzed Suzuki coupling reaction of chloroalkylidene-β-lactones with LB-Phos as the ligand
Pengbin Li, Bo Lü, Chunling Fu and Shengming Ma
DOI: 10.1039/C2OB26365C
Researchers from Taiwan have developed an efficient organocatalytic enantioselective synthesis of spironitrocyclopropanes.
Lin et al. report reaction conditions which allow almost perfect diastereocontrol as well as outstanding enantiocontrol. As nitrocyclopropanes are found in various biologically active natural products and important precursors of bio-relevant cyclopropylamines this new method fills a real synthetic need.
Want to know more? Read the communication for free now! And it will remain free for the next 4 weeks.
An efficient organocatalytic enantioselective synthesis of spironitrocyclopropanes
Utpal Das, Yi-Ling Tsai and Wenwei Lin
DOI: 10.1039/C2OB26943K
Chemists from University of Cambridge, UK, have constructed a new class of multicomponent [2] and [3]catenanes utilizing up to four building blocks and three orthogonal interactions.
In this HOT Communication Miguel Á. Alemán García and Nick Bampos report a one-pot synthesis which uses multiple supramolecular components with distinctly different sets of noncovalent interactions to construct heteroleptic interlocked supramolecular metallomacrocycles.
This Communication is free to access for the next 4 weeks!
Synthesis of a four-component [3]catenane using three distinct noncovalent interactions
Miguel Á. Alemán García and Nick Bampos
DOI: 10.1039/C2OB26587G
Issue 48 of OBC is now online; the last issue of 2012!
Front cover:
Anyone for a game of dominos? In this paper Alessandro Volonterio and colleagues report a one-pot, three-component sequential procedure for the synthesis of diversely 1,3,5- and 1,3,5,5-substituted hydantoins. Volonterio et al. believe that this methodology is especially convenient for the synthesis of spiro-hydantoins, which are particularly interesting bioactive compounds in medicinal chemistry.
Regioselective multicomponent sequential synthesis of hydantoins
Francesca Olimpieri, Maria Cristina Bellucci, Tommaso Marcelli and Alessandro Volonterio
DOI: 10.1039/C2OB26498F
Inside cover:
This colourful cover highlights the work of Atul Goel & Gerhard Bringmann et al., who report a short and efficient synthesis of racemic cis-pterocarpans and highlight a new protocol for the resolution of the enantiomers on a chiral phase through analytical and preparative HPLC.
Synthesis, optical resolution, absolute configuration, and osteogenic activity of cis-pterocarpans
Atul Goel, Amit Kumar, Yasmin Hemberger, Ashutosh Raghuvanshi, Ram Jeet, Govind Tiwari, Michael Knauer, Jyoti Kureel, Anuj K. Singh, Abnish Gautam, Ritu Trivedi, Divya Singh and Gerhard Bringmann
DOI: 10.1039/C2OB25722J
Download both cover articles for free for 6 weeks!
| Also in this issue: |
Get all of this and more today! Go to the issue now…..
Welcome to issue 47 of Organic & Biomolecular Chemistry. So what have we got in store for you this week?
On the front cover:
In this paper by Martin F. Kreutzer and Markus Nett from the Leibniz Institute for Natural Product Research and Infection Biology, report the bioinformatic analysis of an orphan nonribosomal peptide synthetase gene cluster in the rhizobium Cupriavidus taiwanensis. This genome mining strategy led to the isolation of the associated metabolite; a previously unrecognised lipopeptide siderophore.
Genomics-driven discovery of taiwachelin, a lipopeptide siderophore from Cupriavidus taiwanensis
Martin F. Kreutzer and Markus Nett
DOI: 10.1039/C2OB26296G
On the inside cover:
This attractive image highlights the perspective of Jose M. Palomo who describes the current application of click reactions in protein chemistry, the creation of new semisynthetic enzymes by site-specific modifications and the recent design and creation of enzymes with synthetic click activities.
Click reactions in protein chemistry: from the preparation of semisynthetic enzymes to new click enzymes
Jose M. Palomo
DOI: 10.1039/C2OB26409A
Also in this issue is this HOT Communication:
Benzimidazolium-based synthetic chloride and calcium transporters in bacterial membranes
Claude-Rosny Elie, Audrey Hébert, Mathieu Charbonneau, Adam Haiun and Andreea R. Schmitzer
Read the issue today! The cover articles are free to access for 6 weeks and the HOT article is free for 4 weeks.
Vidal et al. perform a detailed experimental study on the relative migratory aptitudes and activating effects of the 1,5- (H, RO, RS) shift / 6p-electrocyclic ring closure, and provide new interesting insights into the formation of highly substituted quinolones.
Want to know what the relative migratory aptitudes are? Or what has the best activating effect? Download the paper for free for the next 4 weeks!
1,5-(H, RO, RS) shift/6π-electrocyclic ring closure tandem processes on N-[(α-heterosubstituted)-2-tolyl]ketenimines: a case study of relative migratory aptitudes and activating effects
Mateo Alajarín, Baltasar Bonillo, Raúl-Angel Orenes, María-Mar Ortín and Angel Vidal
DOI: 10.1039/C2OB27010B
Spanish chemists have completed the stereospecific total synthesis of (+)-myrrhanol C.
(+)-Myrrhanol C is a natural triterpene isolated from mastic gum (the resin of Pistacia lentiscus), a substance well known for its medicinal properties as well as use in various cuisines. The compound itself was used to embalm corpses in ancient Egypt. More recently, it has been recognised as a promising anti-prostate cancer lead. However, before a molecule can be used to develop drugs, a successful synthesis must be developed.
Mastic gum (from Pistacia lentiscus, pictured) has been used for many applications, from treating snakebites to tooth whiteners. © Science Photo Library
Alejandro Barrero and his group at the University of Granada have done just that. Their synthesis starts with (–)-sclareol, a bicyclic diterpene alcohol isolated from clary sage (Salvia sclarea). It then proceeds through a key C–H oxidation step, which is achieved with cytochrome P450 enzyme catalysis by incubating a reaction intermediate with the fungus Mucor plumbeus.
By cultivating clary sage, Barrero can sustainably produce (–)-sclareol, meaning (+)-myrrhanol C can be made on a large scale that is also environmentally friendly.
Read the full story in Chemistry World
And read the OBC paper, highlighted as being HOT by the referees, for free here:
First synthesis of (+)-myrrhanol C, an anti-prostate cancer lead
Victoriano Domingo, Lidia Lorenzo, José F. Quilez del Moral and Alejandro F. Barrero
DOI: 10.1039/C2OB26947C
Researchers in Canada have developed the first benzimidazolium-based synthetic ion channel and shown that it can cause damage to bacterial cells walls.
The movement of ions through cell walls is essential for a host of biological processes. The vast majority of this transportation occurs through ion channels or pores in the cell membrane. Man-made versions of these intracellular transport systems have been the subject of investigation by the supramolecular chemistry community for many years.
Building on their research into imidazolium amphiphiles, they have developed a benzimidazolium-based compound that increases chloride flux in a variety of lipid bilayer systems, and increases bacterial cell wall permeability to calcium ions.
This compound will hopefully inspire new drugs to treat cystic fibrosis, which is caused by mutation of a chloride-ion channel known as the cystic fibrosis transmembrane conductance regulator protein (CFTR). They may also aid in the development of new antibiotics to combat resistant strains of bacteria.
Want to find out more? Read this paper FREE for the next 4 weeks.
Benzimidazolium-based synthetic chloride and calcium transporters in bacterial membranes
Claude-Rosny Elie, Audrey Hébert, Mathieu Charbonneau, Adam Haiun and Andreea R. Schmitzer
DOI: 10.1039/C2OB26966J
Published on behalf of Annabella Newton, Organic & Biomolecular Chemistry web science writer. Annabella Newton is a postdoctoral researcher based in Melbourne, Australia.
One of the simplest and most utilised chemical reactions is the burning of hydrocarbons and while combustion is an excellent way to exploit the energy content of this naturally occurring resource, there is a lot more we can do with the ‘inert’ C-H bond.
C-H activation allows us to convert cheaper hydrocarbon starting materials into more valuable and versatile products; leading to the development of a wide range of reagents and catalysts that activate C-H bonds. To keep you up to date with the latest developments in the field we have created this article collection, where all articles are free to download until 15th December.
Click here for the full list of free articles
In this HOT communication Boris J. Nachtsheim and colleagues at Eberhard Karls University present preliminary results towards a fast and efficient synthetic approach of γ-spirolactams based on an iodine(III)-mediated oxidative spirocyclization of 2-(4-hydroxybenzamido)-acrylates.
In addition Nachtsheim et al. discuss the discovery of an unexpected side reaction, a rare iodine(III)-mediated spirocyclization that gave δ-spirolactones. With fluorinated solvents and modified reaction conditions this side reaction was able to produce δ-spirolactones in yields up to 70%.
Interested? Find out more about these reactions and their mechanisms by downloading this Communication for FREE.
A hypervalent iodine-mediated spirocyclization of 2-(4-hydroxybenzamido)acrylates – unexpected formation of δ-spirolactones
Christian Hempel, Nicole M. Weckenmann, C. Maichle-Moessmer and Boris J. Nachtsheim
DOI: 10.1039/C2OB26815A
