In this work, we report the synthesis and characterization of a bimetallic Prussian blue analogue containing Co and Mn as outer-sphere metals (CoMnHCF). The material was a solid solution and its characterization revealed a chemical composition of Co 2.05 Mn 0.95 [Fe(CN) 6 ] 2 · 12H 2 O. The electrochemistry of this novel material showed the existence of two redox waves displaying quasi-reversible kinetics, as expressed by the larger peak-to-peak separation upon increasing the potential sweep rate. Interestingly, the CoMnHCF solid exhibited high electrocatalytic activity for the oxidation of hydrogen peroxide, thus representing an appealing scaffold for the construction of biosensors. As a proof of concept, cholesterol oxidase was immobilized at the electrode surface by using a sol-gel method, and the cyclic voltammograms were recorded at increasing concentrations of cholesterol. The biosensor showed a detection limit of 30 μM and two linear ranges with excellent sensitivity of 385 mA cm À 2 M À 1 between 50 and 150 μM, and an adequate sensitivity of 80 mA cm À 2 M À 1 between 150 and 1 mM. To the best of our knowledge, this is the first biosensor application of a pre-synthesized bimetallic hexacyanometallate, thus exploiting its potential as an H 2 O 2 electrooxidation catalyst.

Aetokthonotoxin has recently been identified as the cyanobacterial neurotoxin causing Vacuolar Myelinopathy, a fatal neurologic disease, spreading through a trophic cascade and affecting birds of prey such as the bald eagle in the USA. Here, we describe the total synthesis of this specialized metabolite. The complex, highly brominated 1,2’‐biindole could be synthesized via a Somei‐type Michael reaction as key step. The optimised sequence yielded the natural product in five steps with an overall yield of 29 %.

For the first time, the Petasis (borono‐Mannich) reaction is employed for the multicomponent labeling and stapling of peptides. The report includes the solid‐phase derivatization of peptides at the N‐terminus, Lys, and Nϵ‐MeLys side‐chains by an on‐resin Petasis reaction with variation of the carbonyl and boronic acid components. Peptides were simultaneously functionalized with aryl/vinyl substituents bearing fluorescent/affinity tags and oxo components such as dihydroxyacetone, glyceraldehyde, glyoxylic acid, and aldoses, thus encompassing a powerful complexity‐generating approach without changing the charge of the peptides. The multicomponent stapling was conducted in solution by linking Nϵ‐MeLys or Orn side‐chains, positioned at i, i+7 and i, i+4, with aryl tethers, while hydroxy carbonyl moieties were introduced as exocyclic fragments. The good efficiency and diversity oriented character of these methods show prospects for peptide drug discovery and chemical biology.

Neglected tropical diseases affect the world’s poorest populations with soil-transmitted helminthiasis and schistosomiasis being among the most prevalent ones. Mass drug administration is currently the most important control measure, but the use of the few available drugs is giving rise to increased resistance of the parasites to the drugs. Different approaches are needed to come up with new therapeutic agents against these helminths. Fungi are a source of secondary metabolites, but most fungi remain largely uninvestigated as anthelmintics. In this report, the anthelmintic activity of Albatrellus confluens against Caenorhabditis elegans was investigated using bio-assay guided isolation. Grifolin (1) and neogrifolin (2) were identified as responsible for the anthelmintic activity. Derivatives 4–6 were synthesized to investigate the effect of varying the prenyl chain length on anthelmintic activity. The isolated compounds 1 and 2 and synthetic derivatives 4–6, as well as their educts 7–10, were tested against Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum. Prenyl-2-orcinol (4) and geranylgeranyl-2-orcinol (6) showed promising activity against newly transformed schistosomula. The compounds 1, 2, 4, 5, and 6 were also screened for antiproliferative or cytotoxic activity against two human cancer lines, viz. prostate adenocarcinoma cells (PC-3) and colorectal adenocarcinoma cells (HT-29). Compound 6 was determined to be the most effective against both cell lines with IC50 values of 16.1 µM in PC-3 prostate cells and 33.7 µM in HT-29 colorectal cells.

Coordination polymers have received considerable attention in recent years as electrocatalytic materials for the construction of electrochemical sensors. This is due to their high sensitivity and selectivity towards the electrochemical detection of various molecules, particularly pollutants and metabolites, which commonly appear in low concentrations and in complex matrices. In this work, the construction of an electrochemical sensor was performed for the detection of phenylhydrazine, which is a strong pollutant, based on a mixed Ni 2 + Co 2 + transition metal nitroprusside (NiCoNP). NiCoNP was synthesized by chemical coprecipitation, and characterized using Xray diffraction, TGA, and IR and XPS spectroscopies. Its structural characterization indicates that the material was a solid solution, with a cubic Fm � 3m structure and a stoichiometry of Ni 0.59 Co 0.41 [Fe(CN) 5 NO] ⋅ 5H 2 O. The material showed quasireversible electron transfer behavior associated to the charge transfer between the metallic centers of the nitroprusside and the concomitant intercalation of K + ions within the crystal lattice. The sensor based on NiCoNP exhibited a high electrocatalytic activity for the electrooxidation of phenylhydrazine without kinetic limitations, and a wide large linear range (0.5-12 mM), high sensitivity (86.87 μA ⋅ cm À 2 /mM), and LOD of 266 μM. Such device showed a rapid and selective response towards phenylhydrazine. In conclusion, the NiCoNP under study showed a promising electrocatalytic activity for the development of electrochemical sensors.