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The synthesis of a library of molecular water oxidation catalysts based on the Co complex of tris(2-benzimidazolylmethyl)amine is described. Hydrophobicity was identified as the key variable in mediating the catalytic competence of the complexes. The change in this parameter correlates with both the conformational mobility of the ligand core and the structural changes in the local solvent environment around the metal site. The optimal Co complex identified is hydrophobic, because of three semifluorinated side chains. It catalyzes water electro-oxidation efficiently at neutral pH, with an overpotential of 390 mV and a turnover frequency (TOF) of 1.83 s–1 in the absence of soluble Co salts. The catalyst can be immobilized through physisorption, and it remains stable in prolonged electrolysis experiments.

We report a general method for the preparation of quantum dot-labeled viruses through a strain-promoted azide-alkyne cycloaddition (SPAAC) reaction. The quantum dot sample was functionalized with methacrylate-based polymeric imidazole ligands (MA-PILs) bearing dibenzocyclooctyne groups. Enveloped measles virus was labeled with azide groups through the metabolic incorporation of a choline analogue into the host cell membrane, and then linked with the modified QDs. The virus retained its infectious ability against host cells after the modification with MA-PIL capped QDs.

The amine-catalyzed inverse electron demand Diels-Alder reaction of unsymmetrical tetrazines with aldehydes and ketones was investigated. We found that only one regioisomer could be observed when pyrrolidine was applied as the catalyst. Using this reaction, fluorogenic dyes could be developed with a tetrazine unit as the “triggering group”.

Modification of an enveloped measles virus was achieved by metabolic incorporation of azido sugars in host cells through the protein glycosylation process. Based on this, the resulting measles virus particles could be modified with azido groups on the surface glycoproteins, which could be further labeled with fluorescence dyes using a strain-promoted azide-alkyne cycloaddition reaction. We envision this metabolic labeling approach to be applicable to a wide variety of enveloped viruses, allowing the facile conjugation and surface modification.

A series of ethacrynic acid analogues, lacking the alpha,beta-unsaturated carbonyl unit, was synthesized and subsequently evaluated for their ability to inhibit the migration of human breast cancer cells, MCF-7/AZ. Several of the analogues were already active in the low micromolar range, whereas ethacrynic acid itself shows no potential to inhibit the migration of these cancer cells. Preliminary studies show that the presence of one or more methoxy groups at the phenyl ring of ethacrynic acid is important in order for the ethacrynic acid analogues to demonstrate an inhibitory effect on the migration.

In the presence of triphenylphosphine, copper(II) chloride can catalyze an intermolecular ortho-acylation reaction of phenols with aryl aldehydes. The reaction proceeds smoothly with a wide range of starting materials, and furthermore, it can be used to synthesize xanthone derivatives in a single step in high yields.

A Friedel–Crafts reaction of 2,6-dimethoxyphenol in the presence of aluminum chloride and propanoyl or butanoyl chloride, respectively, lead, at elevated temperatures, to a selective cleavage of one of the methoxy groups followed by a selective acylation of the meta position with respect to the phenolic hydroxyl group. Under the same reaction conditions 2-methoxyphenol does not get demethylated; a mechanism to account for these findings is proposed. This reaction gives access to a variety of ortho -acylated catechols. Substituted catechols are widely used in supramolecular chemistry and are precursors of pesticides, flavors, and fragrances. Additionally, catechol moieties are found in various natural products.

In the presence of triphenylphosphine, copper (II) chloride can catalyze an intermolecular ortho-acylation reaction of phenols with aryl aldehydes. The reaction proceeds smoothly with a wide range of starting materials, and furthermore, it can be used to synthesize xanthone derivatives in a single step with high-yields.