Chemoenzymatic Total Synthesis of Sorbicatechol Structural Analogues and Evaluation of Their Antiviral Potential

Sorbicillinoids are fungal polyketides characterized by highly complex and diverse molecular structures, with considerable stereochemical intricacy combined with a high degree of oxygenation. Many sorbicillinoids possess promising biological activities. An interesting member of this natural product family is sorbicatechol A, which is reported to have antiviral activity, particularly against influenza A virus (H1N1). Through a straightforward, one-pot chemoenzymatic approach with recently developed oxidoreductase SorbC, the characteristic bicyclo[2.2.2]octane core of sorbicatechol is structurally diversified by variation of its natural 2-methoxyphenol substituent. This facilitates the preparation of a focused library of structural analogues bearing substituted aromatic systems, alkanes, heterocycles, and ethers. Fast access to this structural diversity provides an opportunity to explore the antiviral potential of the sorbicatechol family.     

Modeling of a Methanol Synthesis Reactor for Storage of Renewable Energy and Conversion of CO2 – Comparison of Two Kinetic Models

The storage of renewable energy over a long time period, via methanol synthesis, will become very important to reach a greenhouse gas‐free energy supply. A steady‐state methanol synthesis flowsheet, containing a 2D pseudo‐homogeneous reactor, flash, and recycle, is modeled in MATLAB. With the kinetic models of Graaf and Bussche & Froment, two frequently used kinetic models for conventional methanol synthesis are compared and evaluated for applicability regarding methanol synthesis from CO₂/H₂. The results are presented for different cases of synthesis gas compositions. Both kinetic models produce similar results when the system is limited by thermodynamic equilibrium. However, differences in reaction rates are observable from the reactor axial molar component profiles of the reaction products.     

Magnetic field enhancement of electrochemical hydrogen evolution reaction probed by magneto-optics

External magnetic fields affect various electrochemical processes and can be used to enhance the efficiency of the electrochemical water splitting reaction. However, the driving forces behind this effect are poorly understood due to the analytical challenges of the available interface-sensitive techniques. Here, we present a set-up based on magneto- and electro-optical probing, which allows to juxtapose the magnetic properties of the electrode with the electrochemical current densities in situ at various applied potentials and magnetic fields. On the example of an archetypal hydrogen evolution catalyst, Pt (in a form of Co/Pt superlattice), we provide evidence that a magnetic field acts on the electrochemical double layer affecting the local concentration gradient of hydroxide ions, which simultaneously affects the magneto-optical and magnetocurrent response.     

Research Platform: Decentralized Energy System for Sector Coupling

Industrial facilities usually need multiple energy subsystems, e.g., for heat, cold, and electric power supply. Normally, these energy subsystems are controlled locally and independent of each other. Coupling of the different subsystems can open up additional potential. Fraunhofer IISB has developed a demonstration and research platform for investigating the benefits of such sector coupling. A major precondition is to understand the energy flows in the system and establish an overall and flexible system control to realize the required algorithms for setting up an intelligent decentralized energy system. Major components of the overall system are various storages, which extend the degree of freedom for sector coupling and increase the effectiveness of the different subsystems.     

Application limits and sensitisation behaviour of the manganese- and nitrogen-alloyed austenitic stainless steel P2000 (X13CrMnMoN18-14-3)

Nickel-free high-nitrogen-alloyed stainless steels like the P2000 (X13CrMnMoN18-14-3) were developed to enhance the strength and corrosion resistance of austenitic stainless steels like 304 and 316 while keeping the typical high ductility. The mechanical and corrosive properties of P2000 were investigated and compared with 304 and 316 to highlight the application opportunities of this new alloy. The microstructure of the solution-annealed condition was characterised by electron backscatter diffraction and the mechanical properties were studied by uniaxial tensile tests, Charpy impact tests and hardness measurements. The passivation behaviour was analysed using the electrochemical potentiodynamic reactivation, whereas the pitting corrosion resistance was compared by pitting potentials and pitting temperatures. However, secondary thermal influences or suboptimal heat treatment can impair the corrosion resistance due to the precipitation of secondary phases and the resulting sensitisation. Thermodynamic calculations and artificial ageing treatment in the range of 500–900°C for up to 100 h were used to determine critical time–temperature parameters for sensitisation. The microstructure of the various aged states was evaluated by scanning electron microscopy and compared with the degrading corrosion resistance characterised by the KorroPad method.     

Gas Chromatographic Enantioseparation of Fluorinated Anesthetics: Single‐Column Performance and Scale‐up Estimation

Results of a study devoted to provide the pure enantiomers of isoflurane and desflurane from racemic mixtures using gas chromatography are presented. For that purpose, a cyclodextrin‐based selector described in earlier work was immobilized on porous glass beads. The adsorption isotherms were determined and applied to predict operating parameters which provide the highest possible productivity of the separation. The analysis included evaluation of the performance of larger columns applying simplifying scale‐up considerations. Using repetitive batches, the method can provide per day with a laboratory scale column approximately 1 g pure enantiomer. Selected model predictions were validated experimentally.