Cobalt–metalloid alloys for electrochemical oxidation of 5-hydroxymethylfurfural as an alternative anode reaction in lieu of oxygen evolution during water splitting

• Jonas Weidner,
• Stefan Barwe,
• Kirill Sliozberg,
• Stefan Piontek,
• Justus Masa,
• Ulf-Peter Apfel and
• Wolfgang Schuhmann

Beilstein J. Org. Chem. 2018, 14, 1436–1445, doi:10.3762/bjoc.14.121

• large scale electrochemical hydrogen production. Advantageously, the oxidation of an alternative substrate at the anode, for example a biomass-derived fuel, allows to generate high value products besides hydrogen concomitantly with an increase in energy conversion efficiency during electrolysis [4

• valuable product is an appealing approach for increasing the competitiveness of the electrochemical hydrogen production. 5-Hydroxymethylfurfural (HMF) is a biomass-derived compound that can be converted to economically more valuable 2,5-furandicarboxylic acid (FDCA) via electrochemical oxidation at a

Spectroelectrochemical studies on the effect of cations in the alkaline glycerol oxidation reaction over carbon nanotube-supported Pd nanoparticles

• Dennis Hiltrop,
• Steffen Cychy,
• Karina Elumeeva,
• Wolfgang Schuhmann and
• Martin Muhler

Beilstein J. Org. Chem. 2018, 14, 1428–1435, doi:10.3762/bjoc.14.120

• oxidation. Keywords: cation effect; electrocatalysis; glycerol oxidation; in situ electrochemistry/IR spectroscopy; Introduction The conversion of biomass to biofuels is a promising process for carbon-neutral energy conversion [1]. First-generation biofuels such as bioethanol or biodiesel are produced

Herpetopanone, a diterpene from Herpetosiphon aurantiacus discovered by isotope labeling

• Xinli Pan,
• Nicole Domin,
• Sebastian Schieferdecker,
• Hirokazu Kage,
• Martin Roth and
• Markus Nett

Beilstein J. Org. Chem. 2017, 13, 2458–2465, doi:10.3762/bjoc.13.242

• -sterilized aqueous solutions (0.05 M) at the time of inoculation. The fermentation was conducted at 30 °C for 7 days. After centrifugation and removal of the biomass, the supernatant was treated with 10% (w/v) XAD-2 resin (Sigma-Aldrich) in order to adsorb the secreted metabolites. The resin was thoroughly

New bio-nanocomposites based on iron oxides and polysaccharides applied to oxidation and alkylation reactions

• Daily Rodríguez-Padrón,
• Alina M. Balu,
• Antonio A. Romero and
• Rafael Luque

Beilstein J. Org. Chem. 2017, 13, 1982–1993, doi:10.3762/bjoc.13.194

• in both the oxidation and alkylation reaction reveals a potential method for the valorization of lignocellulosic biomass. Keywords: alkylation; benzyl alcohol; benzyl chloride; iron oxide; mechanochemistry; microwave-assisted oxidation; polysaccharide; toluene; Introduction Heterogeneous catalysis

• toluene, respectively) could find current application in the valorization of lignocellulosic biomass with heterogeneous catalysis. However, the use of heterogeneous catalysts in the aforementioned reactions usually requires a filtration or centrifugation step to recover the catalyst. In order to simplify

Selective enzymatic esterification of lignin model compounds in the ball mill

• Ulla Weißbach,
• Saumya Dabral,
• Laure Konnert,
• Carsten Bolm and
• José G. Hernández

Beilstein J. Org. Chem. 2017, 13, 1788–1795, doi:10.3762/bjoc.13.173

• “Tailor Made Fuels from Biomass” (TMFB), which are funded by the Excellence Initiative of the German federal and state governments. We are also grateful to the European Union (Marie Curie ITN ‘SuBiCat’ PITN-GA-2013-607044, S.D.) for financial support.

Glycoscience@Synchrotron: Synchrotron radiation applied to structural glycoscience

• Serge Pérez and
• Daniele de Sanctis

Beilstein J. Org. Chem. 2017, 13, 1145–1167, doi:10.3762/bjoc.13.114

• , or cellulose microfibrils from biomass. For this process to be optimal, some fundamental aspects of the structural and ultrastructural characterization of the cellulosic material have to be ascertained. Indeed, the extraction process should be adapted to the specificity of the various sources (e.g

New tricks of well-known aminoazoles in isocyanide-based multicomponent reactions and antibacterial activity of the compounds synthesized

• Maryna V. Murlykina,
• Maryna N. Kornet,
• Sergey M. Desenko,
• Svetlana V. Shishkina,
• Oleg V. Shishkin,
• Aleksander A. Brazhko,
• Vladimir I. Musatov,
• Erik V. Van der Eycken and
• Valentin A. Chebanov

Beilstein J. Org. Chem. 2017, 13, 1050–1063, doi:10.3762/bjoc.13.104

• obtained were evaluated for their antibacterial activity and several of them demonstrated a weak antimicrobial effect, but for most of the compounds a 30–50% increase in biomass of Gram-positive strains (mainly B. subtilis) compared to control was observed. Keywords: 3-amino-5-methylisoxazole; 5-amino-N

• ., anticancer, antidiabetic, etc., because in this case a negative influence on a microflora of the organism is decreased [110]. The other interesting feature of most of the compounds was the 30–50% increase in biomass of Gram-positive strains (mainly B. subtilis) compared to control. As it follows from a brief

• while scaling up the production of biomass with the aim of shortening the time and saving resources [120][121]. Although this is a subject for a future detailed study the results of antibacterial activity allowed outlining the positive tendency. Conclusion In summary, the behavior of 5-amino-N-aryl-1H

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

• Stephen Hill and
• M. Carmen Galan

Beilstein J. Org. Chem. 2017, 13, 675–693, doi:10.3762/bjoc.13.67

• ., graphite or graphene. Conversely bottom-up methodologies rely on the use of a molecular precursor which can be treated in such a way as to seed the formation of a CD. Typical starting materials include amino acids, citric acid, biomass and carbohydrates to name but a few, which can be reacted using thermal

• oligosaccharides or monosaccharide units. Thus, it is unsurprising that these naturally occurring materials have also been used as CD precursors. Many CD syntheses report the use of biomass, particularly sourced from plant matter, which is essentially a huge source of naturally derived polysaccharides combined

Secondary metabolome and its defensive role in the aeolidoidean Phyllodesmium longicirrum, (Gastropoda, Heterobranchia, Nudibranchia)

• Alexander Bogdanov,
• Cora Hertzer,
• Stefan Kehraus,
• Samuel Nietzer,
• Sven Rohde,
• Peter J. Schupp,
• Heike Wägele and
• Gabriele M. König

Beilstein J. Org. Chem. 2017, 13, 502–519, doi:10.3762/bjoc.13.50

• with the MeOH extract (3 × 150 mL) of the slug biomass and the solvents were evaporated. After liquid–liquid separation of the methanolic crude extract (4.5 g) between 100 mL H2O and 3 × 100 mL ethyl acetate (EtOAc), EtOAc solubles (2.2 g) were fractionated by vacuum liquid chromatography (VLC) over

Revaluation of biomass-derived furfuryl alcohol derivatives for the synthesis of carbocyclic nucleoside phosphonate analogues

• Bemba Sidi Mohamed,
• Christian Périgaud and
• Christophe Mathé

Beilstein J. Org. Chem. 2017, 13, 251–256, doi:10.3762/bjoc.13.28

• compounds were evaluated for their activity against a large number of viruses. However, none of them showed significant antiviral activity or cytotoxicity. Keywords: analogue; antiviral; carbocyclic; nucleoside; phosphonate; Introduction Biomass is a valuable resource in search of renewable organic carbon

• catalytic hydrogenation of furfural; the latter is obtained from the dehydration of xylose, a 5-carbon sugar derived from vegetal biomass. Furfuryl alcohol finds widespread application in the chemical industries and for example is employed for the production of synthetic fibers, fine chemicals, etc. In fine

Green chemistry

• Luigi Vaccaro

Beilstein J. Org. Chem. 2016, 12, 2763–2765, doi:10.3762/bjoc.12.273

• recovery and reuse of the materials needed for a synthetic process. It is also very important to promote the use of biomass-derived chemicals that feature an intrinsically lower CO2 consumption. Additionally, the pivotal role of catalysis is indisputable. Significant efforts are being directed towards the

Diels–Alder reactions in confined spaces: the influence of catalyst structure and the nature of active sites for the retro-Diels–Alder reaction

• Ángel Cantín,
• M. Victoria Gomez and
• Antonio de la Hoz

Beilstein J. Org. Chem. 2016, 12, 2181–2188, doi:10.3762/bjoc.12.208

• selectivity and atom economy. Moreover, Diels–Alder cycloadditions in combination with heterogeneous catalysts (i.e. doped-microporous materials) represent an interesting approach for the conversion of biomass feedstock into stable chemicals such as furfural derivatives, platform molecules which can be

Silica-supported sulfonic acids as recyclable catalyst for esterification of levulinic acid with stoichiometric amounts of alcohols

• Raimondo Maggi,
• N. Raveendran Shiju,
• Veronica Santacroce,
• Giovanni Maestri,
• Franca Bigi and
• Gadi Rothenberg

Beilstein J. Org. Chem. 2016, 12, 2173–2180, doi:10.3762/bjoc.12.207

• Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands. Tel: +31-20-5256515 Istituto IMEM-CNR, Parco Area delle Scienze 37/A, I-43124 Parma, Italy 10.3762/bjoc.12.207 Abstract Converting biomass into value-added chemicals holds the key to sustainable long-term carbon resource management. In this

• : esterification; heterogeneous catalysis; renewable feedstocks; supported organic catalysts; sustainable chemistry; Introduction Vegetal biomass is mankind’s only source of renewable carbon on a human timescale. It is abundantly available, with the potential of replacing fossil-based carbon on a scale sufficient

• for covering the worldwide demand for non-fuel chemicals [1][2][3][4]. Currently, the main research thrust is directed at lignocellulose, the most abundant fraction of biomass. The mass composition of lignocellulose could be roughly represented by a 5/3/2 ratio of cellulose, hemicellulose and lignin

Superelectrophilic activation of 5-hydroxymethylfurfural and 2,5-diformylfuran: organic synthesis based on biomass-derived products

• Dmitry S. Ryabukhin,
• Dmitry N. Zakusilo,
• Mikhail O. Kompanets,
• Anton A.Tarakanov,
• Irina A. Boyarskaya,
• Tatiana O. Artamonova,
• Mikhail A. Khohodorkovskiy,
• Iosyp O. Opeida and
• Aleksander V. Vasilyev

Beilstein J. Org. Chem. 2016, 12, 2125–2135, doi:10.3762/bjoc.12.202

• 5-HMF and 2,5-DFF were characterized by NMR spectroscopy in TfOH and studied by DFT calculations. These reactions show possibilities of organic synthesis based on biomass-derived 5-HMF and 2,5-DFF. Keywords: 2,5-diformylfuran; Friedel–Crafts reaction; 5-hydroxymethylfurfural; superacids; zeolites

• molecules, such as alcohols, carboxylic acids, (hetero)aromatic ketones and aldehydes, phenols, etc. These biomass-derived platform chemicals are considered as an alternative and displacement to petroleum chemistry [17][18]. Among all these compounds, the preparation and reaction of 5-hydroxymethylfurfural

• production of new useful organic substances [26][27][28][29][30]. Based on our recent study on the synthesis of 5-HMF and its oxidation to 2,5-diformylfuran (2,5-DFF) [31] (Figure 1), this work is focused on developing methods of organic synthesis on the basis of electrophilic activation of these biomass

Experimental and theoretical insights in the alkene–arene intramolecular π-stacking interaction

• Valeria Corne,
• Ariel M. Sarotti,
• Carmen Ramirez de Arellano,
• Rolando A. Spanevello and
• Alejandra G. Suárez

Beilstein J. Org. Chem. 2016, 12, 1616–1623, doi:10.3762/bjoc.12.158

• , Universidad de Valencia, Valencia 46100, Spain 10.3762/bjoc.12.158 Abstract Chiral acrylic esters derived from biomass were developed as models to have a better insight in the aryl–vinyl π-stacking interactions. Quantum chemical calculations, NMR studies and experimental evidences demonstrated the presence

• affected by the electron density of the aromatic counterpart. Keywords: acrylic esters; asymmetric synthesis; biomass; conformational equilibrium; π-stacking interaction; Introduction Noncovalent interactions have demonstrated to have relevant importance in chemistry and biology [1][2][3][4]. Considering

• an element of stereocontrol in highly selective chemical transformations has been widely explored [9]. In this context, as part of our continuous interest in the development of new tools for asymmetric synthesis using levoglucosenone (a biomass-derived chiral enone) [10][11][12][13][14][15], we

Artificial Diels–Alderase based on the transmembrane protein FhuA

• Hassan Osseili,
• Daniel F. Sauer,
• Klaus Beckerle,
• Marcus Arlt,
• Tomoki Himiyama,
• Tino Polen,
• Akira Onoda,
• Ulrich Schwaneberg,
• Takashi Hayashi and
• Jun Okuda

Beilstein J. Org. Chem. 2016, 12, 1314–1321, doi:10.3762/bjoc.12.124

• support by the Deutsche Forschungsgemeinschaft (DFG) through the International Research Training Group “Selectivity in Chemo- and Biocatalysis” (SeleCa), the excellence cluster “Tailor-made Fuels from Biomass” (TMFB), the JSPS Japan-German Graduate Externship Program, and Grants-in-Aid for Scientific

Elucidation of a masked repeating structure of the O-specific polysaccharide of the halotolerant soil bacteria Azospirillum halopraeferens Au4

• Elena N. Sigida,
• Yuliya P. Fedonenko,
• Alexander S. Shashkov,
• Nikolay P. Arbatsky,
• Evelina L. Zdorovenko,
• Svetlana A. Konnova,
• Vladimir V. Ignatov and
• Yuriy A. Knirel

Beilstein J. Org. Chem. 2016, 12, 636–642, doi:10.3762/bjoc.12.62

• of Sciences (IBPPM RAS, Saratov) and was cultivated under aerobic conditions at 41 °C in a liquid malate medium [8] supplemented with 0.09 M NaCl. In an analogous manner as described before [14][33] the cells were washed from the capsule and dried, LPS was extracted from the biomass (10 g) by the

Antibiotics from predatory bacteria

• Juliane Korp,
• María S. Vela Gurovic and
• Markus Nett

Beilstein J. Org. Chem. 2016, 12, 594–607, doi:10.3762/bjoc.12.58

• : antibiotics; genome mining; Herpetosiphon; myxobacteria; predation; Introduction Microorganisms are major contributors to primary biomass production and nutrient cycling in nature. The composition of a microbial community shapes an ecosystem, but is also responsive to biotic and environmental cues. Predation

Natural products from microbes associated with insects

• Christine Beemelmanns,
• Huijuan Guo,
• Maja Rischer and
• Michael Poulsen

Beilstein J. Org. Chem. 2016, 12, 314–327, doi:10.3762/bjoc.12.34

• required by the insect host to provide necessary nutritional and immunological effectors (obligate symbiont) [37]. The microbiota may account for 1–10% of the insect biomass, implying that the insect, as well as any other higher organism, can be regarded as a multi-organismal entity [38]. Due to

Biocatalysis for the application of CO₂ as a chemical feedstock

• Apostolos Alissandratos and
• Christopher J. Easton

Beilstein J. Org. Chem. 2015, 11, 2370–2387, doi:10.3762/bjoc.11.259

• generation biofuel production processes. In this way, the carbon fixed by plants (biomass) is further transformed into a wide array of products through microbial processing [16]. Genetically engineered plants and algae have been employed to divert carbon flux in planta towards other metabolic products of

• interest, as an alternative to microbial processes [17][18]. Yet another alternative approach is to directly fix the CO2 with microorganisms, circumventing the intermediacy of crop derived biomass [19][20]. This can be done with autotrophic microbes, though these are generally poorly understood, and the

• were photosynthetically active, and the RuBisCO complex showed higher specific activities than the enzyme in the control tobacco line. Algae that utilise efficient variants of RuBisCO for fixation of CO2 have been targeted as a biomass source for a third generation of biofuels, due to their lack of

Synthesis of α,β-unsaturated esters via a chemo-enzymatic chain elongation approach by combining carboxylic acid reduction and Wittig reaction

• Yitao Duan,
• Peiyuan Yao,
• Yuncheng Du,
• Jinhui Feng,
• Qiaqing Wu and
• Dunming Zhu

Beilstein J. Org. Chem. 2015, 11, 2245–2251, doi:10.3762/bjoc.11.243

• acids are abundant from natural resources, aromatic carboxylic acids could be prepared by the degradation of lignin, an unused and abundant component of biomass, although the effective methods for the degradation of lignin need to be developed. These carboxylic acids could be reduced to their

Engineering Pichia pastoris for improved NADH regeneration: A novel chassis strain for whole-cell catalysis

• Martina Geier,
• Christoph Brandner,
• Gernot A. Strohmeier,
• Mélanie Hall,
• Franz S. Hartner and
• Anton Glieder

Beilstein J. Org. Chem. 2015, 11, 1741–1748, doi:10.3762/bjoc.11.190

• ), thereby contributing to biomass production on methanol. Modifying the dissimilatory part of the MUT pathway has already been shown to improve the substrate conversion by NADH-dependent enzymes in P. pastoris [7]. Over-expression of the formaldehyde dehydrogenase, which was identified as the main

• linking methanol to biomass production, were deleted. In the course of 38 h, the optical density of the P. pastoris Δdas1 Δdas2 cultures on methanol doubled. This remaining carbon flux into cellular metabolism might also enable the continuation of protein expression and thus biocatalyst production, while

• turnover numbers in the reduction of racemic acetoin (kcat = 98,000 min−1) [22]. In an initial screening step, BDH1 transformants in the respective wild type and knock-out backgrounds were evaluated by performing acetoin conversions in the 96 well deep-well format. After biomass production on a D-glucose

Highly selective generation of vanillin by anodic degradation of lignin: a combined approach of electrochemistry and product isolation by adsorption

• Dominik Schmitt,
• Carolin Regenbrecht,
• Marius Hartmer,
• Florian Stecker and
• Siegfried R. Waldvogel

Beilstein J. Org. Chem. 2015, 11, 473–480, doi:10.3762/bjoc.11.53

• renewable feedstocks in the world [1][2][3]. Moreover, lignin represents the largest source of aromatic compounds among renewables and can be considered as non-food biomass. It usually occurs as a major waste fraction of the pulping industry on a multimillion ton scale [4]. This source has the potential to

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

• Alexander Burkhart and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1951–1958, doi:10.3762/bjoc.10.203

• present study we evaluate the thermoresponsive behavior of solutions of polymers containing 2-methacrylamido-caprolactam as a comonomer. The used α-amino-ε-caprolactam is obtained from biomass through a combination of biological fermentation and chemical processes [14]. Results and Discussion Racemic α

Organic synthesis using photoredox catalysis

• Axel G. Griesbeck

Beilstein J. Org. Chem. 2014, 10, 1097–1098, doi:10.3762/bjoc.10.107

• delivers a constant stream of oxygen and organic biomass. We should acknowledge this fact with humbleness, especially because we have not been able yet to mimic this process in a reliable way even after decades of intense research. The basic mechanistic principle behind photosynthesis is photoredox