Front Covers

through out the years we have had several key publication that made it to the front page of journals here are a few of them

Catal. Sci. Technol. 20, (2016)

Nitrile reductases catalyse a two-step reduction of nitriles to amines. This requires the binding of two NADPH molecules during one catalytic cycle. For the nitrile reductase from E. coli (EcoNR) mass spectrometry studies of the catalytic mechanism were performed. EcoNR is dimeric and has no Rossman fold. It was demonstrated that during catalysis each active site binds one substrate molecule. NADPH binds independent of the substrate. The PreQ0 binding pocket of the active site is not involved in the binding of NADPH; this is in conflict with an earlier hypothesis.

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Catal. Sci. Technol. 5, (2015)

Water is omnipresent and essential. Yet at the same time it is a rather unreactive molecule. The direct addition of water to CC double bonds is therefore a challenge not answered convincingly. In this perspective we critically evaluate the selectivity and the applicability of the different catalytic approaches for water addition reactions: homogeneous, heterogeneous and bio-catalytic. Here we would like to discuss how to speed up water addition and even make it selective.

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Green Chemistry 15-12 (2013)

The one-pot combination of alcohol dehydrogenase-catalysed asymmetric reduction of 2-azido ketones and Pd nanoparticle-catalysed hydrogenation of the resulting azido alcohols, gives access to both enantiomers of aromatic 1,2-amino alcohols in high yields and excellent optical purity (ee >99%). Furthermore, we demonstrate the incorporation of an upstream azidolysis and a downstream acylation step into the one-pot system, thus establishing a highly integrated synthesis of the antiviral natural product (S)-tembamide in 73% yield (ee >99%) over 4 steps. Avoiding the purification and isolation of intermediates in this synthetic sequence leads to an unprecedentedly low ecological footprint, as quantified by the E-factor and solvent demand.

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Nature: Chemistry 5-2 (2013)

The complementary catalytic reactivities of enzymes and transition-metal complexes often hint at the possibility of useful cascade reactions, but these two classes of catalyst often inactivate one another. A team of researchers from the UK, the Netherlands and Switzerland now report a solution to this important problem, which involves anchoring a metal complex inside a host enzyme (as shown on the cover) to produce a metal catalyst that is compatible with natural enzymes. 

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Chem. Soc. Rev. 42 (2013)

Hydroxynitrile lyases are a versatile group of enzymes that are applied both in the laboratory and on an industrial scale. What makes them particularly interesting is that to date five structurally unrelated categories of hydroxynitrile lyases have been discovered. Given their great importance they have often been immobilised utilising many different methodologies. Therefore the hydroxynitrile lyases are ideally suited to compare different immobilisation methods and their dependence on the structural features of the enzyme in question, since the activity is the same in all cases. This review examines all the different immobilisation methods applied to hydroxynitrile lyases and draws conclusions on the effect of the approach. 

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ChemCatChem 5-6 (2013)

The cover picture shows how hydroxynitrile lyases do not catalyze the addition of cyanide to an imine, which is mediated rather by the water present in the reaction media. In their Communication on p. 1304 ff., G. Torrelo et al. report that this addition, which is part of the classical Strecker synthesis, occurs in a non-enzymatic way and two structurally different hydroxynitrile lyases do not catalyze this reaction. These results discard the promiscuous catalytic activity attributed to these enzymes more than 10 years ago. 

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Angewante Chemie 52-4 (2013)

The recognition of tumors is possible through the dynamic formation of cyclic boronate esters between the diol moiety of the overexpressed marker sialic acid and a phenylboronic acid (pba) targeting vector. MRI signal intensity enhancement at the tumor site as a result of the accumulation and prolonged retention of a GdIII-dota-en-pba targeting contrast agent after its intravenous injection into a melanoma mouse xenograft has been demonstrated. 

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Chemical Communications 53 (2012)

A bi-enzymatic cascade for the redox-isomerisation of allylic alcohol is presented. Coupling of an alcohol dehydrogenase to an enoate reductase has been successfully applied in one pot for the isomerisation of an allylic alcohol to the corresponding ketone. Critical parameters for yield and selectivity have been investigated. 

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European Journal of Inorganic Chemistry 12 (2012)

The front cover picture gives an impression on the breadth of coverage of this Cluster Issue on Metal-Based Magnetic Resonance Imaging Probes.

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Chemistry: A european journal 7 (2011)

The catalytic power … of Al-Zr-TUD-1 is symbolized on the cover, in which a tiger is pacified (i.e., citronellal is cyclized) by this catalyst. The seal of the university after which the catalyst is named—Technische Universiteit Delft 1 (TUD-1)—is depicted in the bottom right-hand corner. For more information see the Full Paper on page 2077 ff. by U. Hanefeld et al. 

 

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Green Chemistry 9 (2011)

When challenged by a difficult reduction reaction, a chemist should always also consider biocatalysis in synthesis planning. The inherent selectivity of enzymes has been known for many decades now and the practical applicability of biocatalysis has undergone dramatic improvements rendering it a true alternative to established chemocatalysis. In this contribution recent developments in the field of enzymatic reduction using whole cells and isolated enzymes are reviewed.  

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Chemical Communications 38 (2008)

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Dalton Transactions 17 (2008)

 

 

 

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