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Diameter Control of GaSb Nanowires Revealed by In Situ Environmental Transmission Electron Microscopy

Several nanowire properties are strongly dependent on their diameter, which is notoriously difficult to control for III–Sb nanowires compared with other III–V nanowires. Herein environmental transmission electron microscopy is utilized to study the growth of Au nanoparticle seeded GaSb nanowires in situ. In this study, the real time changes to morphology and nanoparticle composition as a result of

Novel unit B cryptophycin analogues as payloads for targeted therapy

Cryptophycins are naturally occurring cytotoxins with great potential for chemotherapy. Since targeted therapy provides new perspectives for treatment of cancer, new potent analogues of cytotoxic agents containing functional groups for conjugation to homing devices are required. We describe the design, synthesis and biological evaluation of three new unit B cryptophycin analogues. The O-methyl gro

Straightforward Regeneration of Reduced Flavin Adenine Dinucleotide Required for Enzymatic Tryptophan Halogenation

Flavin-dependent halogenases are known to regioselectively introduce halide substituents into aromatic moieties, for example, the indole ring of tryptophan. The process requires halide salts and oxygen instead of molecular halogen in the chemical halogenation. However, the reduced cofactor flavin adenine dinucleotide (FADH 2 ) has to be regenerated using a flavin reductase. Consequently, coupled

United and divided : Early modern economic history in Finnish and Swedish academic literature

In this chapter, we analyze Finnish and Swedish economic history research on these countries’ common past (prior to 1809) and the early modern era (defined here as between 1500 and 1850). Using extensive bibliometric databases, we show that even when they focus on the early modern era, economic historians most often analyze Finland and Sweden in terms of their modern borders. Researchers based in

Flavin-Dependent Halogenases from Xanthomonas campestris pv. campestris B100 Prefer Bromination over Chlorination

Flavin-dependent halogenases selectively introduce halogen substituents into (hetero-)aromatic substrates and require only molecular oxygen and halide salts for this regioselective oxidative CH-functionalization. Genomic analysis of Xanthomonas campestris pv. campestris B100 identified three novel putative members of this enzyme class. They were shown to introduce halogen substituents into, e. g.,

Intra-specific variation in avian malaria : Linking infection dynamics to haplotypes

Avian Malaria infects thousands of species of birds across the Aves class. The most widespread (geographically and phylogenetically)morphological species is Plasmodium relictum, and of that, the mitochondrial lineage of SGS1 is the most common and invasive. It infects146 bird species, with large differences in infection outcome, from low intensity chronic disease to shorter, highly virulent infect

X-ray, structural assignment and molecular docking study of dihydrogeodin from Aspergillus Terreus TM8

A re-cultivation of the thermophilic fungus Aspergillus terreus TM8, and working up of its extract afforded the dichloro-benzophenone derivative, dihydrogeodin (1) in addition to the butyrolactones I (2), V (3) and VI (4). A literature surveying revealed one recent structural assignment trial for dihydrogeodin (1), however, with some inaccuracies. We report herein a full assignment of dihydrogeodi

Diverse polyketides and alkaloids from Penicillium sp. KHMM : structural elucidation, biological and molecular docking studies

As a continuation of our earlier research concerning the investigation of microbial bioactive secondary metabolites from the terrestrial Penicillium sp.KH Link 1809 isolate KHMM, the fungus was re-cultivated on a large scale to explore its bioactive compounds intensively. Fifteen compounds, including seven alkaloids (1-7), one sesquiterpene (8), an acetylenic system (9), two sterols, and sphengoli

Ergostane-type steroids from the Cameroonian ‘white tiama’ Entandrophragma angolense

Two new ergostane-type steroids named tiamenones A and B (1–2) were isolated from the bark of Entandrophragma angolense (Meliaceae) along with ten known compounds identified as 20S-hydroxy-4,6,24(28)-ergostatrien-3-one (3), 3β,7α,20β-trihydroxyergosta-5,24(28)-diene (4), 3β,5α-dihydroxyergosta-7,22-diene (5), stigmasterol, β-sitosterol, β-amyrin, oleanolic acid, asperphenamate, sucrose and daucost

Synthesis, in vitro cytotoxicity activity against the human cervix carcinoma cell line and in silico computational predictions of new 4-arylamino-3-nitrocoumarin analogues

A new series of 4-arylamino-3-nitrocoumarin analogues (4–18) have been synthesized and characterized by sophisticated spectroscopic techniques (1H NMR, 13C NMR) and mass spectrometry. All the new synthesized compounds were evaluated for their in vitro cytotoxic activity against the human cervix carcinoma cell line (KB-3-1) using resazurin assay with (+)-griseofulvin as the positive control (IC50 =

Phenothiazine-Biaryl-Containing Fluorescent RGD Peptides

Cyclic RGD peptides are well-known ligands of integrins. The integrins αVβ3 and α5β1 are involved in angiogenesis, and integrin αVβ3 is abundantly present on cancer cells, thus representing a therapeutic target. Hence, synthetic and biophysical studies continuously are being directed towards the understanding of ligand-integrin interaction. In this context, the development of versatile synthetic s

Structure of apo flavin-dependent halogenase Xcc4156 hints at a reason for cofactor-soaking difficulties

Flavin-dependent halogenases regioselectively introduce halide substituents into electron-rich substrates under mild reaction conditions. For the enzyme Xcc4156 from Xanthomonas campestris, the structure of a complex with the cofactor flavin adenine dinucleotide (FAD) and a bromide ion would be of particular interest as this enzyme exclusively brominates model substrates in vitro. Apo Xcc4156 crys

Three phragmalin-type limonoids orthoesters and the structure of odoratone isolated from the bark of Entandrophragma candollei (Meliaceae)

The phytochemical exploration of the Entandrophragma candollei stem bark extract led to the isolation and identification of twenty compounds including three undescribed phragmalin-class limonoids named encandollens C–E (1–3), the undescribed protolimonoid 5 together with sixteen known compounds. The structures of all the isolated compounds were determined by interpretation of their spectroscopic a