Author Archive

HOT: β-thiolactones with higher cytotoxic activity than corresponding β-lactones

β-lactones are potentially useful as drugs for several diseases, due to their ability to inhibit key biological functions.  However, their high reactivity in physiologically relevant conditions also renders their half-life very short and limits the potential drug applications.

To combat this David Crich and colleagues at the Institut de Chimie des Substances Naturelles, CNRS, have synthesised a series of β-thiolactone analogs of β-lactones, on the basis that they would have greater persistence in aqueous media without too much loss of reactivity with the intended targets, as compared to β-lactam analogues.  The synthesised β-thiolactones were assayed for cytotoxicity against several human cancer cell lines, where they showed greater activity than the corresponding lactones and lactams.

Interested? The article is free to access for 4 weeks:

Exploring the potential of the β-thiolactones in bioorganic chemistry
Sylvain Aubry, Kaname Sasaki, Laure Eloy, Geneviève Aubert, Pascal Retailleau, Thierry Cresteil and David Crich
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05967J

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Fluorinated cyclic amino acids on the cover of Issue 19

On the cover of Issue 19 is an article from Ference Fülöp and colleagues from the University of Szeged and the University of Valencia.

They have developed a synthetic route to fluorinated β-aminocyclohexene or cyclohexane esters from a bicyclic β-lactam via selective hydroxylation and hydroxy–fluorine exchange.  Despite the potential of fluorinated cyclic amino acids for medicinal chemistry applications, only a handle of other fluorinated derivatives have been reported so far.

This article is part of a forthcoming Organic & Biomolecular Chemistry web theme issue on Foldamer Chemistry – check back soon for related articles.

Regio- and diastereoselective fluorination of alicyclic β-amino acids
Loránd Kiss, Enikő Forró, Santos Fustero and Ferenc Fülöp
Org. Biomol. Chem., 2011, 9, 6528-6534, Advance Article
DOI: 10.1039/C1OB05648D

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RSC e-membership launched

This week, the RSC launched a new product, RSC e-membership, allowing anyone to access an electronic version of Chemistry World through a MyRSC account and to enjoy the benefits of electronic networking via this professional online community for £20/year.

Subscribers to this do not benefit from the professional recognition or any of the other many services and discounts available to RSC Members, but it allows chemists from around the world, many already members of another chemical society in their own country, to benefit from the highly-esteemed content in Chemistry World and the networking opportunities offered from MyRSC, which now stands at over 11,000 members. The RSC e-membership also allows subscribers to join a virtual specialist interest group on MyRSC. If you are interested in joining, please visit www.rsc.org/emembership.

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HOT: reactivity of p-nitrostyrene oxide as an alkylating agent

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

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Recent advances in indole syntheses: New routes for a classic target

This Perspective article from Rubén Vicente at the University of Oviedo, Spain, reviews the most relevant and inventive approaches towards the preparation of the ubiquitous indole motif in the last five years.

Areas covered in this review:

  • Indole syntheses from o-alkynylanilines and derivatives
  • Indole syntheses from o-haloanilines
  • Indole syntheses from o-alkynylhaloarenes or o-dihaloarenes
  • Indole syntheses from b-(pseudo)halostyrene derivatives
  • Indole syntheses from o-propargylanilines
  • Indole syntheses from acetophenone derivatives
  • Indole syntheses from arylhydrazines and related compounds
  • Indole syntheses via nitrene or carbene insertions
  • Indole syntheses via processes involving a C–C- or N–N-cleavage
  • Indole syntheses through C–H-bond functionalizations

Despite the impressive list of clever synthetic routes presented, Dr Vicente highlights that more sustainable and efficient routes are still needed for future developments – so why not take a look and get synthesising? The article is free to access for four weeks:

Recent advances in indole syntheses: New routes for a classic target
Rubén Vicente
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05750B, Perspective

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RCM synthesis of amphidinolactone A core on the cover of Issue 16

On the front cover of this issue is work from Debendra Mohapatra at the Indian Institute of Chemical Technology, together with colleagues at Hyderabad University and King Saud University on the ring-closing metathesis based synthesis of the macrolactone core of amphidinolactone A.

The convergent synthesis achieved the macrolactone core in 32% yield and demonstrated the steric hinderance resulting from protecting groups in the RCM reaction.  PMB (p-methoxybenzyl ether) protecting groups on the macrolactonization precursor prevented the RCM reaction from proceeding, but  simple de-protection to the subsequent diol achieved the 13-membered lactone ring system present in amphidinolactone A in 76% yield.  Further work to incorporate the the RCM reaction into the total synthesis of amphidinolactone A is ongoing.

Ring-closing metathesis (RCM) based synthesis of the macrolactone core of amphidinolactone A
Debendra K. Mohapatra, Manas R. Pattanayak, Pragna P. Das, Tapas R. Pradhan and J. S. Yadav
Org. Biomol. Chem., 2011,
DOI: 10.1039/C1OB05335C

View the rest of the articles in Issue 16

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HOT: vinylogous Mukaiyama-Michael reaction for synthesis of γ-subsituted butenolides

The butenolide skeleton is one of the more common to natural products and bioative compounds, thus its synthesis has afforded much attention from synthetic chemists in recent years.  Here, Xiamong Feng and colleagues from the Key Laboratory of Green Chemistry and Technology at Sichuan University have devised a simple route that affords the desired γ-butenolide compounds in high yields with high levels of selectivity.

By using a chiral N,N‘-dioxide-scandium catalyst in an asymmetric vinylogous Mukaiyama–Michael reaction they were able to form highly functionalized chiral γ-substituted butenolides with broad substrate scope, with up to 92% ee.  The pathway is air stable and produces product on a gram scale.

For the full details download the article – it’s free to access for the next four weeks:

Highly enantioselective synthesis of γ-substituted butenolides via the vinylogous Mukaiyama–Michael reaction catalyzed by a chiral scandium(III)–N,N′-dioxide complex
Qi Zhang, Xiao Xiao, Lili Lin, Xiaohua Liu and Xiaoming Feng
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05558E

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Multicomponent reactions and click chemistry on the cover of Issue 15

Work from Asish K. Bhattacharya (National Chemical Laboratory, India) and co-workers features on the front cover of Issue 15.  Their paper describes the FeCl3 catalysed four-component condensation of diamines, acetone and phosphites in the presence of molecular sieves to yield benzodiazepinyl phosphonates which demonstrate protease inhibition activity against clostripain.

An efficient synthesis of benzodiazepinyl phosphonates as clostripain inhibitors via FeCl3 catalyzed four-component reaction
Asish K. Bhattacharya, Kalpeshkumar C. Rana, Dnyaneshwar S. Raut, Vaibhav P. Mhaindarkar and Mohamad I. Khan
Org. Biomol. Chem.
, 2011, 9, 5407-5413
DOI: 10.1039/C0OB01102A

On the inside front cover we have work from Boris Vauzeilles (CNRS) et al. on the synthesis of neoglycoconjugates as glycosidase inhibitors through click connection of the iminosugar deoxynojirimycin and functionalised adamantanes.

Selection of the biological activity of DNJ neoglycoconjugates through click length variation of the side chain
Nicolas Ardes-Guisot, Dominic S. Alonzi, Gabriele Reinkensmeier, Terry D. Butters, Caroline Norez, Frédéric Becq, Yousuke Shimada, Shinpei Nakagawa, Atsushi Kato, Yves Blériot, Matthieu Sollogoub and Boris Vauzeilles
Org. Biomol. Chem., 2011, 9, 5373-5388
DOI: 10.1039/C1OB05119A

Both articles are free to access for 6 weeks, so why not take a look? You can also view the rest of the issue online here

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HOT: carbene catalysis to make courmarin derivatives

A new nucleophilic heterocyclic carbene mediated transformation of 2H-chromene-3-carboxaldehydes has been reported by Vijay Nair, CSIR, et al.

The team were attempting to make endocyclic homoenolates from 2H-chromene-3-carboxaldehyde, but instead discovered a novel transformation which resulted in 3-methyl coumarin.  Coumarins have demonstrated important bioactives and therefore the group envisage that this reaction may be a useful future route to coumarin derivatives.

This hot piece of synthesis is currently free to access for four weeks:

A novel NHC-catalyzed transformation of 2H-chromene-3-carboxaldehydes to 3-methyl-2H-chromen-2-ones
Vijay Nair, C. R. Sinu, R. Rejithamol, K. C. Seetha Lakshmi and Eringathodi Suresh
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05325F

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Organocatalysis – announcing a joint ChemComm–OBC web theme

We are delighted to announce a forthcoming ChemCommOrganic & Biomolecular Chemistry (OBC) web themed issue:

Organocatalysis

Guest editors: Keiji Maruoka (Kyoto University), Hisashi Yamamoto (University of Chicago), Liu-Zhu Gong (University of Science and Technology of China) and Benjamin List (Max-Planck-Institut für Kohlenforschung)

Submission deadline: 29th February 2012


We are now inviting submissions for this web theme, which will be a celebration of current achievements and future perspectives in this exciting field of research.

ChemComm and OBC are both welcoming urgent communications; OBC also welcomes full papers. Please feel free to submit to either or both journals.

All manuscripts will undergo strict peer review and should be very important and conceptually significant in accord with the ChemComm and OBC mandates.

Publication of the peer-reviewed articles will occur without delay to ensure the timely dissemination of the work. The articles will then be assembled on the RSC Publishing Platform as a web-based thematic issue, to permit readers to consult and download individual contributions from the entire series.

Communications for this web theme can be submitted anytime from now until 29th February using ChemComm’s and OBC’s web submission system. Please add the phrase ‘organocatalysis web theme‘ in the comments to the editor field.

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