A new colorimetric assay for antioxidant capacity and photostability

The antioxidant capacity of cysteine, glutathione, N‐acetylcysteine, and ascorbic acid to reduce Methylene Blue to colourless Leucomethylene Blue was analysed. Interestingly, transient exposure of Leucomethylene Blue to sunlight resulted in a reversible oxidation reaction and thus, provided a fast, easy, and simple quantitative assay to determine antioxidant capacity and photostability of biologically relevant antioxidants.     

Structure–Activity Relationships of 2‐Sufonylpyrimidines as Quorum‐Sensing Inhibitors to Tackle Biofilm Formation and eDNA Release of Pseudomonas aeruginosa

Drug‐resistant Pseudomonas aeruginosa (PA) strains are on the rise, making treatment with current antibiotics ineffective. Hence, circumventing resistance or restoring the activity of antibiotics by novel approaches is of high demand. Targeting the Pseudomonas quinolone signal quorum sensing (PQS‐QS) system is an intriguing strategy to abolish PA pathogenicity without affecting the viability of the pathogen. Herein we report the structure–activity relationships of 2‐sulfonylpyrimidines, which were previously identified as dual‐target inhibitors of the PQS receptor PqsR and the PQS synthase PqsD. The SAR elucidation was guided by a combined approach using ligand efficiency and ligand lipophilicity efficiency to select the most promising compounds. In addition, the most effective inhibitors were rationally modified by the guidance of QSAR using Hansch analyses. Finally, these inhibitors showed the capacity to decrease biofilm mass and extracellular DNA, which are important determinants for antibiotic resistance.     

Identification and Structure–Activity Relationship Studies of Small‐Molecule Inhibitors of the Methyllysine Reader Protein Spindlin1

The methyllysine reader protein Spindlin1 has been implicated in the tumorigenesis of several types of cancer and may be an attractive novel therapeutic target. Small‐molecule inhibitors of Spindlin1 should be valuable as chemical probes as well as potential new therapeutics. We applied an iterative virtual screening campaign, encompassing structure‐ and ligand‐based approaches, to identify potential Spindlin1 inhibitors from databases of commercially available compounds. Our in silico studies coupled with in vitro testing were successful in identifying novel Spindlin1 inhibitors. Several 4‐aminoquinazoline and quinazolinethione derivatives were among the active hit compounds, which indicated that these scaffolds represent promising lead structures for the development of Spindlin1 inhibitors. Subsequent lead optimization studies were hence carried out, and numerous derivatives of both lead scaffolds were synthesized. This resulted in the discovery of novel inhibitors of Spindlin1 and helped explore the structure–activity relationships of these inhibitor series.     

Imide‐containing ladder polyphenylsilsesquioxanes with high thermal stability and thermoplastic properties

This work reports for the first time the synthesis of ladder polyphenylsilsesquioxanes containing imide building blocks as parts of the main parallel chains. The ladder structure of the synthesized polymers was documented by means of small angle X‐ray scattering (SAXS) measurements. The obtained ladder polymers exhibit stability with respect to decomposition up to temperatures as high as 460°C; additionally, they have melting points far below their decomposition temperatures, which make them interesting candidate materials for thermoplastic processing. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40085.     

Blended Learning – ein innovatives Weiterbildungskonzept für die Technische Chemie

The ever‐increasing and ever‐changing challenges of the job market require professionals to constantly attend extra occupational education programs. Professionals furthermore express their desire for a compatibility of family and work. Therefore, a general concept for extended vocational training in the field of natural science and technology was developed based on blended learning. As an example, the concept was implemented and tested on the basis of the extended vocational training course “tc‐compact^BL” in Chemical Technology.     

Rapeseed Proteins for Paperboard Coating

Protein samples of rapeseed were prepared with different compositions as protein isolate, protein concentrate and acetylated protein concentrate. They showed functional properties which are consolidated in the coating. The manufactured protein samples were tested in a pilot‐scale paperboard coating plant. The results indicated that the use of rapeseed proteins in the coating preparation is technically feasible and that the color and roughness of the coated paperboard show no negative effect on the quality. Industry printing experiments with this coated paperboard achieved the standard quality.