Research articles

The natural product fumagillol has been exploited as a stereochemically rich scaffold for the synthesis of a structurally unique, chemically diverse library with chemotypes distinctly different from the parent structure. Thus, fumagillol has been remodelled into a diverse array of isoindoles, isoquinolines, furans, mopholinones and benzoxazepines.

The polyprenylated polycyclic acylphloroglucines (PPAPs) are a family of natural products in which a common core is decorated with four different substituents. Here, a synthetic strategy is presented that separates the core building steps from the core decorating steps, offering a general solution to the synthesis of these natural products that will allow investigation of their biological activities.

Multiple redox reaction pathways exist in proteins containing several cysteines. A technique termed mechanical uncaging is now demonstrated, allowing the release of a single reactive cysteine within a protein and the unequivocal observation of subsequent thiol/disulfide exchanges. Mechanical uncaging of reactive groups is useful for studying chemical kinetics in a synchronized manner.

Cellular membrane lipids play key roles in cell regulation. Here, an environmentally sensitive fluorophore is attached to a protein that binds to a key signalling lipid to produce a membrane lipid sensor. This strategy allows sensitive, quantitative, spatiotemporal imaging of the lipid concentration in mammalian cells.

At water's surface, its network of hydrogen-bonds is abruptly interrupted, conferring distinct properties on interfacial water from bulk water. Understanding aqueous interfaces is essential for many environmental, technological and biophysical systems, and now the pathways and rates of energy transfer at the water/air interface are elucidated using a surface-specific ultrafast spectroscopic technique.

The flow of vibrational energy into reactants and out of products plays a critical role in nearly every chemical reaction. Here, a time-resolved ultrafast microscopic map of energy flow is provided for a thermal bimolecular chemical reaction that takes place in dichloromethane, a typical organic solvent.

Stereoselective Suzuki–Miyaura cross-coupling reactions involving non-benzylic secondary alkylboronates are notoriously challenging. Here, an enantioselective synthesis of 1,1-diboronyl compounds using asymmetric conjugate borylation, followed by chemoselective mono cross-coupling with inversion at the diboron centre, is used to produce highly enantioenriched benzylic or allylic boronates, which themselves are useful reagents for a number of processes.

Molecules that bind to DNA for extended periods can modulate its transcription or other biological processes. Kinetic studies on the non-covalent complex formed by a threading tetra-intercalator and a DNA double-helix have now revealed a multi-step association, and a particularly slow dissociation leading to sequence specificity and a 16-day half-life.

Insight into the active zeolitic domains of catalyst particles used in fluid catalytic cracking is limited by the particles' complex nature, but is crucial to improving these billion dollar catalysts. Now, a staining method allows confocal fluorescence microscopy to probe within single catalyst particles, and correlate Brønsted acidity distributions to catalytic activity.

2,2′-bipyridine ligands coordinate to metals to form chiral propeller-like complexes. Now, this chirality is shown to be controlled by the coordination of 2,2′-bipyridine ligands that bear helical oligopeptides, which incorporate chiral amino acids at positions remote from the metal centre. This chirality is further translated, via the metal centre, to other achiral-oligopeptide-containing ligands.

Well-defined molecular polyhydrides composed of two substantially different types of metals — such as rare-earth and d transition metals — are interesting both in terms of structure and potential properties, but have been largely unexplored so far. Now, a series of such hydride clusters are reported and are found to exhibit unprecedented structural features as well as unique hydrogen addition and release properties.

The self-replication process of a giant vesicle encapsulating double-stranded DNA has been observed, which represents a supramolecular approach to the construction of a protocell. Growth and division of the vesicle occurred rapidly on addition of a membrane precursor, and amplified DNA was distributed amongst the resulting daughter giant vesicles.

Variable-temperature mass spectrometry, isotopic labelling and computational analysis have been used to characterize a metastable non-haem oxo-iron(V) intermediate generated at cryogenic temperatures, as well as to study its cis-dihydroxylation reaction with olefins. The study provides experimental evidence for the existence of this powerful and biologically important oxidant, under conditions relevant to catalysis.

One of the bottlenecks for the development of sustainable artificial photosynthesis is the water oxidation reaction, which too often relies on expensive and toxic metals. Now, coordination complexes of readily available, environmentally benign iron are found to catalyse homogeneous water oxidation to O₂ with high efficiency.

Adding one further base pair to the classic Watson–Crick scheme not only expands the genetic code but also offers opportunities to modify the structure and function of DNA. It has now been shown that an artificial metal–salen base pair can be enzymatically incorporated into DNA duplexes and even amplified by PCR.

A short, synthetic peptide has been prepared that mimics much of the assembly process of natural collagen. Electrostatic interactions are used to create a sticky-ended structure, which in turn self-assembles through several levels of structural hierarchy from peptide to triple helix to nanofibre and finally to hydrogel.

Candidates for 'quantum spin liquid' materials are rare and often composed of two-dimensional kagome arrays of d⁹ centres. Analogous systems based on d¹ metal ions may confer different properties, but there are no previously known examples. An inorganic–organic hybrid vanadium d¹ material has now been prepared that seems to be an excellent candidate for a spin-liquid ground state.

G-quadruplex structures in telomeric DNA inhibit the action of telomerase — an enzyme over-expressed in many cancer cells. Small molecules that stabilize the formation of G-quadruplex structures are therefore of interest as potential cancer treatments. Here, a platform is described that allows the interactions between small-molecule ligands and human telomeric G-quadruplexes to be measured at the single-molecule level.

The natural product thiostrepton is known to have anticancer properties but its mechanism of action is not known. Here, it is shown that thiostrepton binds to the protein FOXM1, preventing its interaction with several gene promoters and inhibits their expression. This illustrates the druggability of transcription factors, and provides a molecular basis for targeting FOXM1.

The outer surfaces of single-walled carbon nanotubes (SWNTs) are known to participate in a range of chemical reactions, but the inner surfaces have so far been thought to be somewhat unreactive. Now, it has been shown that electron-beam irradiation of rhenium–fullerene complexes inside SWNTs can trigger reactions at the inner wall to form protrusions on the nanotube surface.