Highly Efficient Transfer Hydrogenation Catalysis with Tailored Pyridylidene Amide Pincer Ruthenium Complexes

The rational optimization of homogeneous catalysts requires ligand platforms that are easily tailored to improve catalytic performance. Here, it is demonstrated that pyridylidene amides (PYAs) provide such a platform to custom-shape transfer hydrogenation catalysts with exceptional activity.The complexes are active in the catalytic transfer hydrogenation of ketones, with activities directly encoded by the PYA substitution pattern.

[Full Papers]

Philipp Melle, Jan Thiede, Daniela A. Hey, Prof. Dr. Martin Albrecht

doi.org/10.1002/chem.202001145

Antimicrobial Peptide Mimetics Based on a Diphenylacetylene Scaffold: Synthesis, Conformational Analysis, and Activity

AMPed up against resistance: Antimicrobial peptide (AMP) mimetics based on a diphenylacetylene scaffold were investigated. The most active compound was found to adopt a defined structure in anionic membrane and aqueous trifluoroethanol environments, and to display species-selective antibacterial activity.

[Full Papers]

Dr. Hayden Peacock, Dr. Sónia Troeira Henriques, Dr. Aurélie H. Benfield, Dr. Alysha G. Elliott, Dr. Jinghui Luo, Dr. James Luccarelli, Dr. Masanobu Nagano, Prof. David J. Craik, Prof. Andrew D. Hamilton

doi.org/10.1002/cmdc.202000474

Isomerism and Biradical Character of Tetrapnictide Dianions: A Computational Study

A high-level computational study on tetrapnictide dianions Pn42- (Pn = P, As, Sb, Bi) is presented. The calculations reveal that out of three isomers (square-planar, butterfly and capped-triangle), the square planar isomers are generally most stable and show considerable biradical character. Calculated reactions toward alkenes confirm that this unusual electronic structure has significant implications on the reactivity of the Pn42- dianions.

[Full Papers]

Dr. Peter Coburger, Prof. Dr. Robert Wolf, Prof. Dr. Hansjörg Grützmacher

doi.org/10.1002/ejic.202000422

Uncommon overoxidative catalytic activity in a new halo-tolerant alcohol dehydrogenase

Enzymatic catalysis: An unusual alcohol dehydrogenase has been identified from the halo-adapted bacterium H. elongata. HeADH-II shows a great stability to polar solvents and high salt concentration as well as uncommon characteristics such as the lack of enantiopreference and the capability of overoxidizing alcohols to carboxylic acids. To increase the process yields and allowing cofactor recycling, HeADH-II was coupled with a NADH-oxidase from L. pentosus (LpNOX).

[Full Papers]

Dr. Martina L. Contente, Noemi Fiore, Pietro Cannazza, Dr. David Roura Padrosa, Prof. Francesco Molinari, Dr. Louise Gourlay, Prof. Francesca Paradisi

doi.org/10.1002/cctc.202001112

Fast-Charge Limitations for Graphite Anodes with Si as Capacity-Enhancing Additive

Are Si nanoparticles limiting fast-charging in graphite-Si blends? The charge capabilities of graphite electrodes containing different amounts of Si nanoparticles as capacity enhancing additive are investigated. Tracking the cell resistance, in dependence of Si content, suggests a bottleneck in the early stages of lithiation, when the alloying reaction is the primary process. Two common strategies are examined to improve the charge capability of these electrode blends.

[Articles]

Dr. Fabian Jeschull, Dr. Sigita Trabesinger

doi.org/10.1002/batt.202000177

Trace Iridium Engineering on Nickel Hydroxide Nanosheets as High-active Catalyst for Overall Water Splitting

Electrocatalytic Water Splitting: A facile one-step route has been developed to design a series of Ir-doped Ni(OH)2 nanosheets, realizing significantly improved bifunctional performance for both HER and OER in alkaline and neutral electrolytes.

[Full Papers]

Dr. Yun Tong, Hainiao Mao, Qiong Sun, Dr. Pengzuo Chen, Dr. Fei Yan, Dr. Jiyang Liu

doi.org/10.1002/cctc.202000952

EFMC, Medicinal Chemistry and Chemical Biology in Europe

A scientific continuum in constant evolution: This article is a discussion of the trends in medicinal chemistry and chemical biology in Europe, as seen from the European Federation for Medicinal Chemistry (EFMC). We review some of the needs and forces that shape this discipline, including networking and cross-fertilization, the integration of new technologies, digitalization and the use of outsourcing for the benefit of productivity and scientific excellence.

[Editorial]

Dr. Yves P. Auberson

doi.org/10.1002/cmdc.202000178

The European Federation for Medicinal Chemistry (EFMC) Best Practice Initiative: Validating Chemical Probes

What are chemical probes and why are they important? Chemical probes are designed to selectively address a biological question; this is distinctly different from a drug, which is designed to produce a clinical outcome! Simple guidelines can be used to generate high-quality chemical probes and obtain reliable data to further our understanding of human biology and disease.

[Viewpoints]

Dr. Jean Quancard, Prof. Brian Cox, Dr. Dirk Finsinger, Dr. Stéphanie M. Guéret, Dr. Ingo V. Hartung, Dr. Hannes F. Koolman, Dr. Josef Messinger, Prof. Dr. Gianluca Sbardella, Prof. Dr. Stefan Laufer

doi.org/10.1002/cmdc.202000597

The “Carbonyl Story” and Beyond; Experiences, Lessons and Implications

Lessons in discovery and development: The way to bring a 99mTc imaging agent into and through clinical trials is a long one. Although “carbonyl technology” has been known for almost two decades, only one compound made it that far. The different reasons for this are discussed in the paper together with scientific developments inspired by but beyond the carbonyl technology.

[Viewpoints]

Prof. Dr. Roger Alberto

doi.org/10.1002/cbic.202000387

Bis(6-diphenylphosphino-acenaphth-5-yl)sulfoxide: A New Ligand for Late Transition Metal Complexes

The new ligand bis(6-diphenylphosphinoacenaphth-5-yl)sulfoxide, [6-(Ph2P)-5-Ace-6]2-SO, forms a variety of transition metals complexes with sulfur-metal interactions.

[Full Papers]

Fabio Meyer, Dr. Emanuel Hupf, Dr. Enno Lork, Dr. Simon Grabowsky, Dr. Stefan Mebs, Dr. Jens Beckmann

doi.org/10.1002/ejic.202000610

The Threshold Photoelectron Spectrum of Fulvenone: A Reactive Ketene Derivative in Lignin Valorization

Fulvenone, a reactive ketene in lignin catalytic pyrolysis, was synthesized and characterized in situ using threshold photoelectron spectroscopy with synchrotron radiation. Two cationic states, strongly coupled via a conical intersection, contribute to the spectrum.

[Articles]

Patrick Hemberger, Zeyou Pan, Andras Bodi, Jeroen A. van Bokhoven, Thomas K. Ormond, G. Barney Ellison, Nadav Genossar, Joshua H. Baraban

doi.org/10.1002/cphc.202000477

N-Butylpyrrolidinone for Solid-Phase Peptide Synthesis is Environmentally Friendlier and Synthetically Better than DMF

A greener route: Solid-phase peptide synthesis suffers from the required large amounts of N,N-dimethylformamide (DMF) solvent. Here, DMF is replaced with the green solvent N-butylpyrrolidinone (NBP), which is beneficial in two well-documented side reactions in peptide synthesis, racemization and aspartimide formation. The use of NBP renders a lower or equal level of racemization in the amino acids more prone to this side reaction than DMF, and the aspartimide formation is clearly lower when NBP is used as solvent.

[Full Papers]

Dr. Ashish Kumar, Dr. Mahama Alhassan, Dr. John Lopez, Prof. Fernando Albericio, Prof. Beatriz G. de la Torre

doi.org/10.1002/cssc.202001647

Evaluation of Biodegradable Glucose Based Surfactants as a Promoting Medium for the Synthesis of Peptidomimetics with the Coumarin Scaffold

6-O-Glucose-4-phenylbutyrate was used successfully as promoting aqueous reaction medium for the synthesis of fourteen different α-acyloxy carboxamides with the biologically relevant coumarin scaffold. Two different one-pot protocols; chemical and chemoenzymatic, based on the usage of biodegradable surfactants for the synthesis of target products were developed. The application of an aqueous solution of 6-O-glucose 4-phenylbutyrate as the reaction medium had the pivotal impact of the reaction rate providing target α-acyloxy carboxamides with the yields up to 65 %.

[Full Papers]

Dr. Daniel Paprocki, Dr. Dominik Koszelewski, Arleta Madej, Dr. Anna Brodzka, Prof. Peter Walde, Prof. Ryszard Ostaszewski

doi.org/10.1002/slct.202002266

Nitrogen-Incorporated Cobalt Sulfide/Graphene Hybrid Catalysts for Overall Water Splitting

Bifunctional cobalt catalyst: A hybrid catalyst constructed from N-doped CoS2 nanoparticles on N,S-co-doped graphene nanosheets (N−CoS2/G) is produced by a facile route and exhibits excellent bifunctional activity for both the hydrogen and oxygen evolution reactions in alkaline electrolyte. The unique morphology of hierarchical structure guarantees a large active area, high electrical conductivity, and penetration of the electrolyte, thus improving the kinetics of water splitting.

[Full Papers]

Dr. Yun Tong, Qiong Sun, Dr. Pengzuo Chen, Lu Chen, Dr. Zhaofu Fei, Prof. Paul J. Dyson

doi.org/10.1002/cssc.202001413

Hybridization of Fossil- and CO2-Based Routes for Ethylene Production using Renewable Energy

A closer look: The direct electroreduction of CO2 and the “green” methanol dehydration toward ethylene (where methanol is produced via CO2 hydrogenation) are compared with the fossil-based technology for a range of power and CO2 sources. A hybrid ethylene plant combining fossil and CCU technologies is revealed as an optimal strategy to smooth the transition toward a decarbonized chemical industry.

[Full Papers]

Iasonas Ioannou, Sebastiano C. D'Angelo, Dr. Antonio J. Martín, Prof. Javier Pérez-Ramírez, Prof. Gonzalo Guillén-Gosálbez

doi.org/10.1002/cssc.202001312

Front Cover: Light-Harvesting Supramolecular Polymers: Energy Transfer to Various Polyaromatic Acceptors (Eur. J. Org. Chem. 30/2020)

The Front Cover shows an illustration of a self-assembled, artificial light-harvesting complex. Supramolecular polymer fibers are formed in an aqueous environment from short phosphodiester-linked phenanthrene oligomers, shown here in blue. The fibers can be doped with acceptor chromophores, such as benzo(a)pyrene, which is shown in red, intercalated into the aromatic stack of phenanthrenes. After excitation of phenanthrene, the absorbed energy is transferred along the phenanthrene wire to a nearby acceptor molecule, which relaxes via fluorescence. More information can be found in the Communication by R. Häner et al.

[Cover Picture]

Jovana Jevric, Dr. Simon M. Langenegger, Dr. Robert Häner

doi.org/10.1002/ejoc.202001037

Ammonium Salt-Catalyzed Ring-Opening of Aryl-Aziridines with β-Keto Esters

The quaternary ammonium salt-catalyzed addition of β-keto esters to aryl-aziridines gives access to structurally diverse target molecules with two consecutive stereocenters.

[Full Papers]

Victoria Haider, Viktoria Kreuzer, Dr. Maximilian Tiffner, Dr. Bernhard Spingler, Dr. Mario Waser

doi.org/10.1002/ejoc.202000916

Methanol as a Hydrogen Carrier: Kinetic and Thermodynamic Drivers for its CO2-Based Synthesis and Reforming over Heterogeneous Catalysts

Why not both? Although CO2-based methanol synthesis as well as steam reforming are deeply investigated, few studies linking both fields exist. Herein, kinetic and thermodynamic driving forces of both transformations are explored over various classes of heterogeneous catalysts, identifying key requirements for a catalyst to become applicable in either reaction. This work alleviates the translation of findings between the two fields and sets a basis for the development of a single-reactor methanol-based hydrogen storage unit.

[Full Papers]

Matthias S. Frei, Dr. Cecilia Mondelli, Marion I. M. Short, Prof. Dr. Javier Pérez-Ramírez

doi.org/10.1002/cssc.202001518

Polymerizable Oxime Esters: An Efficient Photoinitiator with Low Migration Ability for 3D Printing to Fabricate Luminescent Devices

An efficient oxime ester photoinitiator with low migration can be used to fabricate a luminescent object with high resolution and accuracy using a digital light processing (DLP) 3D printer.

[Articles]

Wanwan Qiu, Junzhe Zhu, Dr. Kurt Dietliker, Dr. Zhiquan Li

doi.org/10.1002/cptc.202000146

Zinc Phosphate Nanoparticles Produced in Saliva

Water-soluble zinc compounds are frequently added to food and cosmetic products as trace element supplements. They form nanoparticles upon contact with saliva. Their chemical and structural evolution was subsequently followed using small-angle X-ray scattering and X-ray absorption spectroscopy. The observed chemical transformation and the quantified particle growth provide valuable information for biological and toxicological studies.

[Full Papers]

Patrick E. J. Saloga, Dr. Glen J. Smales, Dr. Adam H. Clark, Dr. Andreas F. Thünemann

doi.org/10.1002/ejic.202000521

Convergent Evolution of Fungal Cysteine Dioxygenases

Synchronicity: Numerous agaricomycetes contain an unusual cysteine dioxygenase (CDO) that emerged by gene duplication and adaptation from an ergothioneine biosynthetic sulfoxide synthase. It is unrelated to the thiol dioxygenases that occur in animals, plants, and bacteria. The activity of type II CDOs depends on the presence of TMH, thus synchronizing cellular cysteine oxidation with ergothioneine production. OK!

[Communications]

Sebastian Flückger, Nico V. Igareta, Florian P. Seebeck

doi.org/10.1002/cbic.202000317

Increased Lipophilicity of Halogenated Ruthenium(II) Polypyridyl Complexes Leads to Decreased Phototoxicity in vitro when Used as Photosensitizers for Photodynamic Therapy

One up, one down: RuII polypyridyl complexes are prime candidates for the development of new photosensitizers for photodynamic therapy. Increasing their lipophilicity could result in improved pharmacological properties. The relationship between lipophilicity and in vitro phototoxicity of halogenated RuII complexes was investigated.

[Full Papers]

Dr. Saonli Roy, Elisa Colombo, Dr. Robin Vinck, Dr. Cristina Mari, Dr. Riccardo Rubbiani, Dr. Malay Patra, Dr. Gilles Gasser

doi.org/10.1002/cbic.202000289

Evaluation of 5H-Thiazolo[3,2-α]pyrimidin-5-ones as Potential GluN2A PET Tracers

New tools for GluN2A-containing NMDA receptors have been discovered through the optimization of 5H-thiazolo[3,2-α]pyrimidin-5-one derivatives. The radioligand [18F]7b provided high-quality images in autoradiographic studies, while its tritiated analogue [3H2]15b allowed the development of a radioligand binding assay, useful for the study of GluN2A-containing NMDA receptors and the optimization of allosteric modulators binding at the GluN1-GluN2A interface.

[Full Papers]

Yingfang He, Dr. David M. Whitehead, Dr. Emmanuelle Briard, Dr. Shin Numao, Dr. Linjing Mu, Prof. Roger Schibli, Prof. Simon M. Ametamey, Dr. Yves P. Auberson

doi.org/10.1002/cmdc.202000340

Reexamination of the Ergothioneine Biosynthetic Methyltransferase EgtD from Mycobacterium tuberculosis as a Protein Kinase Substrate

Conformer conundrum: The histidine methyltransferase EgtD produces N-α-trimethylhistidine as the first intermediate of ergothioneine biosynthesis in M. tuberculosis. This enzyme can be regulated by kinase-mediated phosphorylation. However, in vitro characterization of this process suggests that folded EgtD is a poor substrate for protein kinase D (PknD).

[Communications]

Alice Maurer, Prof. Dr. Florian P. Seebeck

doi.org/10.1002/cbic.202000232

Coumarin-Tagged Dinuclear Trithiolato-Bridged Ruthenium(II)⋅Arene Complexes: Photophysical Properties and Antiparasitic Activity

The (para)site for treatment: Thirteen coumarin-diruthenium(II)⋅arene conjugates were evaluated against a transgenic T. gondii strain grown in human foreskin fibroblasts (HFF). The IC50 values ranged from 105 to 735 nM, with nine compounds displaying a lower IC50 than the standard drug pyrimethamine. TEM of T. gondii-infected HFF showed that treatment predominantly affected the parasites’ mitochondrion.

[Full Papers]

Oksana Desiatkina, Emilia Păunescu, Martin Mösching, Nicoleta Anghel, Ghalia Boubaker, Yosra Amdouni, Andrew Hemphill, Dr. Julien Furrer

doi.org/10.1002/cbic.202000174

Synthesis and Biological Evaluation of Endocannabinoid Uptake Inhibitors Derived from WOBE437

To elucidate the key structural features underlying the specific inhibitory activity of WOBE437, we conducted a comprehensive SAR study on almost 80 WOBE437 analogues. Several variants exhibited potencies in the sub-100 nM range and were highly selective over inhibition of the endocannabinoid-degrading fatty acid amide hydrolase. However, none of the analogues surpassed the potency of WOBE437.

[Full Papers]

Dr. Patrick Mäder, Dr. Ruben Bartholomäus, Dr. Simon Nicolussi, Alice Baumann, Melanie Weis, Dr. Andrea Chicca, Dr. Mark Rau, Dr. Ana Catarina Simão, Prof. Dr. Jürg Gertsch, Prof. Dr. Karl-Heinz Altmann

doi.org/10.1002/cmdc.202000153

Two-Stage Polyelectrolyte Assembly Orchestrated by a Clock Reaction

Around the clock: A cationic polyelectrolyte is assembled with temporal control by means of the formaldehyde-sulfite clock reaction. Electrostatic interactions template microscopic complexes, which are then crosslinked covalently to lock-in a preformed structure. The final particle size can be controlled simply by tuning either the concentrations of components, or the initial pH value.

[Full Papers]

Christian C M. Sproncken, Dr. Berta Gumí-Audenis, Dr. Guido Panzarasa, Prof. Dr. Ilja K. Voets

doi.org/10.1002/syst.202000005