Quantitative analysis of air-oxidation reactions of thiolate-protected gold nanoclusters.

The interaction of dioxygen (O) with inorganic nanomaterials is one of the most essential steps to understanding the reaction mechanism of O-related reactions. However, quantitative analyses for O-binding processes and subsequent oxidation reactions on the surface are still elusive, whereas the reaction of O with molecules such as transition metal complexes has been widely explored. Herein, we have quantitatively evaluated reaction processes of air-oxidation reactions of atomically precise thiolate-protected Au nanoclusters ([Au(SR)]) as a model of O activation by inorganic nanomaterials.

Structure-activity relationship studies on vitamin D-based selective SREBP/SCAP inhibitor KK-052.

Vitamin D metabolites block lipid biosynthesis by promoting degradation of the complex of sterol regulatory element-binding protein (SREBP) and SREBP cleavage-activating protein (SCAP) independent of their effects on the vitamin D receptor (VDR). We previously reported the development of KK-052, the first vitamin D-based SREBP inhibitor that mitigates hepatic lipid accumulation without VDR-mediated calcemic action in mice. Herein we extend our previous work to synthesize KK-052 analogues.

Open-[60]fullerene-aniline conjugates with near-infrared absorption.

Two open-[60]fullerene-aniline conjugates were synthesized, in which the two-fold addition of diamine gave a thiazolidine-2-thione ring on the [60]fullerene cage in the presence of CS. By increasing the number of ,-dimethylaniline moieties, the absorption edge was considerably shifted up to 1200 nm owing to effective acceptor-donor interactions.

Importance of two-dimensional cation clusters induced by protein folding in intrinsic intracellular membrane permeability.

We investigated the cell penetration of Sp1 zinc finger proteins (Sp1 ZF) and the mechanism which the total cationic charge and distribution of cationic residues on the protein surface affect intracellular trafficking. Sp1 ZFs showed intrinsic cell membrane permeability. The intracellular transfer of Sp1 ZFs other than 1F3 was dependent on the total cationic charge.

Rice husk-derived nano-SiO assembled on reduced graphene oxide distributed on conductive flexible polyaniline frameworks towards high-performance lithium-ion batteries.

By combining rice husk-derived nano-silica and reduced graphene oxide and then polymerizing PANI by polymerization, we created polyaniline-coated rice husk-derived nano-silica@reduced graphene oxide (PANI-SiO@rGO) composites with excellent electrochemical performance. ATR-FTIR and XRD analyses confirm the formation of PANI-SiO@rGO, implying that SiO@rGO served as a template in the formation of composites. The morphology of PANI-SiO@rGO was characterized by SEM, HRTEM, and STEM, in which SiO nanoparticles were homogeneously loaded on graphene sheets and the PANI fibrous network uniformly covers the SiO@rGO composites.

Discovery of a phase-separating small molecule that selectively sequesters tubulin in cells.

Phase-separated membraneless organelles or biomolecular condensates play diverse functions in cells, however recapturing their characteristics using small organic molecules has been a challenge. In the present study, cell-lysate-based screening of 843 self-assembling small molecules led to the discovery of a simple organic molecule, named huezole, that forms liquid droplets to selectively sequester tubulin. Remarkably, this small molecule enters cultured human cells and prevents cell mitosis by forming tubulin-concentrating condensates in cells.

A two-step screening to optimize the signal response of an auto-fluorescent protein-based biosensor.

Auto-fluorescent protein (AFP)-based biosensors transduce the structural change in their embedded recognition modules induced by recognition/reaction events to fluorescence signal changes of AFP. The lack of detailed structural information on the recognition module often makes it difficult to optimize AFP-based biosensors. To enhance the signal response derived from detecting the putative structural change in the nitric oxide (NO)-sensing segment of transient receptor potential canonical 5 (TRPC5) fused to enhanced green fluorescent protein (EGFP), EGFP-TRPC5, a facile two-step screening strategy, first and second, was applied to variants of EGFP-TRPC5 deletion-mutated within the recognition module.

Photochemical conversion of CO to CO by a Re complex: theoretical insights into the formation of CO and HCO from an experimentally detected monoalkyl carbonate complex.

Triethanolamine (TEOA) has been used for the photocatalytic reduction of CO, and the experimental studies have demonstrated that the TEOA increases the catalytic efficiency. In addition, the formation of a carbonate complex has been confirmed in the Re photocatalytic system where DMF and TEOA are used as solvents. In this study, we survey the reaction pathways of the photocatalytic conversions of CO to CO + HO and CO to CO + HCO by -Re(bpy)(CO)Br in the presence of TEOA using density functional theory (DFT) and domain-based local pair natural orbital coupled cluster approach, DLPNO-CCSD(T).

Manifold dynamic non-covalent interactions for steering molecular assembly and cyclization.

Deciphering rich non-covalent interactions that govern many chemical and biological processes is crucial for the design of drugs and controlling molecular assemblies and their chemical transformations. However, real-space characterization of these weak interactions in complex molecular architectures at the single bond level has been a longstanding challenge. Here, we employed bond-resolved scanning probe microscopy combined with an exhaustive structural search algorithm and quantum chemistry calculations to elucidate multiple non-covalent interactions that control the cohesive molecular clustering of well-designed precursor molecules and their chemical reactions.

Cation recognition on a fullerene-based macrocycle.

Heterocyclic orifices in cage-opened fullerene derivatives are regarded as potential ligands toward metals or ions, being reminiscent of truncated fullerenes as a hypothetical class of macrocycles with spherical π-conjugation. Among a number of cage-opened examples reported thus far, the coordination ability and dynamic behavior in solution still remained unclear due to difficulties in structural determination with multiple coordination sites on the macrocycles. Herein, we present the detailed solution dynamics of a cage-opened C derivative bearing a diketo bis(hemiketal) moiety in the presence of alkali metal ions.

Enhanced enzymatic activity exerted by a packed assembly of a single type of enzyme.

In contrast to the dilute conditions employed for biochemical studies, enzymes are spatially organized at high density in cellular micro-compartments. In spite of being crucial for cellular functions, enzymatic reactions in such highly packed states have not been fully addressed. Here, we applied a protein adaptor to assemble a single type of monomeric enzyme on a DNA scaffold in the packed or dispersed states for carbonic anhydrase.

Ultrafast-charging and long cycle-life anode materials of TiO-bronze/nitrogen-doped graphene nanocomposites for high-performance lithium-ion batteries.

Emerging technologies demand a new generation of lithium-ion batteries that are high in power density, fast-charging, safe to use, and have long cycle lives. This work reports charging rates and specific capacities of TiO(B)/N-doped graphene (TNG) composites. The TNG composites were prepared by the hydrothermal method in various reaction times (3, 6, 9, 12, and 24 h), while the N-doped graphene was synthesized using the modified Hummer's method followed by a heat-treatment process.

Ruddlesden-Popper phases of lithium-hydroxide-halide antiperovskites: two dimensional Li-ion conductors.

Lithium-oxide-halide and lithium-hydroxide-halide antiperovskites were explored for potential electrolytes in all-solid Li-ion batteries. A single-phase sample of the Ruddlesden-Popper (RP) series of compounds, LiBr(LiOHBr) with double antiperovskite LiOHBr layers and rigid rock-salt type LiBr layers, was obtained. Li-ion vacancies are introduced in the double antiperovskite LiOHBr layers but not in the LiBr layers and induce two-dimensional Li-ion conduction with low activation energy by mediating Li-ion hopping.

An orifice design: water insertion into C.

Using an open-cage C derivative possessing an orifice designed on the basis of computational studies, we have experimentally demonstrated the quantitative encapsulation of HO as well as effective conversion into HO@C in an overall yield remarkably higher than the previously reported methods by 2-5 times.

Structure-dependent antiviral activity of catechol derivatives in pyroligneous acid against the encephalomycarditis virus.

The pyrolysis product, wood vinegar (WV), from Japanese larch exhibited strong antiviral activity against the encephalomycarditis virus (EMCV). Catechol, 3-methyl-, 4-methyl-, 4-ethyl-, and 3-methoxycatechol, and 2-methyl-1,4-benzenediol were identified as the major antiviral compounds. The viral inhibition ability of these compounds was affected by the structure and position of the substituent group attached to the aromatic skeleton.

Characterization of Na Li NiMnO as a positive electrode material for lithium-ion batteries.

The relationship between the charge-discharge properties and crystal structure of Na Li NiMnO (0.010 ≤ ≤ 0.013, 0.

Piceatannol exhibits anti-inflammatory effects on macrophages interacting with adipocytes.

Piceatannol (PIC), a natural analog of resveratrol (RES), is a phytochemical found in passion fruit seeds. To clarify the effects of PIC on obesity-induced inflammation in adipose tissue, we investigated the anti-inflammatory activity of PIC-related compounds (PIC, RES, and metabolites from PIC) in culture models of obese adipose tissue. Lipopolysaccharide (LPS) and conditioned medium from 3T3-L1 adipocytes (3T3-L1-CM) enhanced proinflammatory gene expression and synthesis of nitric oxide (NO), tumor necrosis factor- (TNF-), and interleukin-6 (IL-6) in RAW264.