Hierarchically porous materials were developed using a two-step procedure by (1) the stacking of high-nitrogen-content polymer nanoparticles to produce inter-particle mesoporous space and (2) chemical activation to create intra-particle micropores. The materials exhibited efficient CO 2 uptake and enhanced CO 2 /N 2 selectivity, which is 40% higher than that of the control material without a hierarchical structure.

Redox catalysis: Aryl amides, imides, lactams, and dipeptides are obtained through a direct Staudinger ligation mediated by phosphine‐based redox catalysis (see scheme). Mechanistic studies indicate the involvement of a phosphonium carboxylate intermediate that leads to a 1,3‐acyl migration and thus results in CN bond formation.

Streptococcus pyogenes, or group A Streptococcus (GAS), is a human bacterial pathogen that can manifest as a range of diseases from pharyngitis and impetigo to severe outcomes such as necrotizing fasciitis and toxic shock syndrome. GAS disease remains a global health burden with cases estimated at over 700 million annually and over half a million deaths due to severe infections(1). For over 100 years, a clinical hallmark of diagnosis has been the appearance of complete (beta) haemolysis when grown in the presence of blood. This activity is due to the production of a small peptide toxin by GAS known as streptolysin S. Although it has been widely held that streptolysin S exerts its lytic activity through membrane disruption, its exact mode of action has remained unknown. Here, we show, using high-resolution live cell imaging, that streptolysin S induces a dramatic osmotic change in red blood cells, leading to cell lysis. This osmotic change was characterized by the rapid influx of Cl(-) ions into the red blood cells through SLS-mediated disruption of the major erythrocyte anion exchange protein, band 3. Chemical inhibition of band 3 function significantly reduced the haemolytic activity of streptolysin S, and dramatically reduced the pathology in an in vivo skin model of GAS infection. These results provide key insights into the mechanism of streptolysin S-mediated haemolysis and have implications for the development of treatments against GAS.

The impact of altered amino acid metabolism on cancer progression is not fully understood. We hypothesized that a metabolic transcriptome shift during metastatic evolution is crucial for brain metastasis. Here we report a powerful impact in this setting caused by epigenetic upregulation of glutamate decarboxylase 1 (GAD1), a regulator of the GABA neurotransmitter metabolic pathway. In cell-based culture and brain metastasis models, we found that downegulation of the DNA methyltransferase DNMT1 induced by the brain microenvironment-derived clusterin resulted in decreased GAD1 promoter methylation and subsequent upregulation of GAD1 expression in brain metastatic tumor cells. In a system to dynamically visualize cellular metabolic responses mediated by GAD1, we monitored the cytosolic NADH:NAD+ equilibrium in tumor cells. Reducing GAD1 in metastatic cells by primary glia cell co-culture abolished the capacity of metastatic cells to utilize extracellular glutamine, leading to cytosolic accumulation of NADH and increased oxidative status. Similarly, genetic or pharmacological disruption of the GABA metabolic pathway decreased the incidence of brain metastasis in vivo. Taken together, our results show how epigenetic changes in GAD1 expression alter local glutamate metabolism in the brain metastatic microenvironment, contributing to a metabolic adaption that facilitates metastasis outgrowth in that setting.

Seawater desalination plays a critical role in addressing the global water shortage challenge. Directional Solvent Extraction (DSE) is an emerging non-membrane desalination technology that features the ability to utilize very low temperature waste heat (as low as 40 °C). This is enabled by the subtly balanced solubility properties of directional solvents, which do not dissolve in water but can dissolve water and reject salt ions. However, the low water yield of the state-of-the-art directional solvent (decanoic acid) significantly limits its throughput and energy efficiency. In this paper, we demonstrate that by using ionic liquid as a new directional solvent, saline water can be desalinated with much higher production rate and thus significantly lower the energy and exergy consumptions. The ionic liquid identified suitable for DSE is [emim][Tf2N], which has a much (~10×) higher water yield than the currently used decanoic acid. Using molecular dynamics simulations with Gibbs free energy calculations, we reveal that water dissolving in [emim][Tf2N] is energetically favorable, but it takes significant energy for [emim][Tf2N] ions to dissolve in water. Our findings may significantly advance the DSE technology as a solution to the challenges in the global water-energy nexus.

A phosphorus(III)-mediated formal [4+1]-cycloaddition of 1,2-dicarbonyls and o-quinone methides to provide 2,3-dihydrobenzofurans is described. By exploiting the carbene-like nature of dioxyphospholenes, dihydrobenzofurans bearing a quaternary center at C2 are obtained in 30-92% yield with diastereoselectivities up to ≥20:1. This study highlights the subtle steric interactions involved in the [4+1]-cycloannulation and the impact they have on yield and stereoselectivity in dihydrobenzofuran formation.

[reaction: see text] An enantioselective entry to the skeleton of the tremulane sesquiterpenes is described. The approach features a series of efficient transition metal-catalyzed reactions commencing with an enantioselective rhodium(II)-catalyzed intramolecular cyclopropanation followed by a regioselective allylic alkylation and a diastereoselective rhodium(I)-catalyzed [5 + 2] cycloaddition. This strategy was applied to the first enantioselective syntheses of tremulenediol A and tremulenolide A.

A chlorophosphite-modified, Staudinger-like acylation of azides involving a highly chemoselective, direct nucleophilic acyl substitution of carboxylic acids is described. The reaction provides the corresponding amides with analytical purity in 32-97% yield after a simple aqueous workup without the need for a pre-activation step. The use of chlorophosphites as dual carboxylic acid-azide activating agents enables the formation of acyl C-N bonds in the presence of a wide range of nucleophilic and electrophilic functional groups, including amines, alcohols, amides, aldehydes, and ketones. The coupling of carboxylic acids and azides for the formation of alkyl amides, sulfonyl amides, lactams, and dipeptides is described.