Symmetrically branched glyceryl oligomers possessing thiol at the apex were synthesized. After treatment of the surface of a silver-plated metal piece, its water contact angle was significantly decreased.

The crystal structure of a bisporphyrin cleft molecule revealed that the head-to-head dimeric structure is directed by the intermolecular self-complementary hydrogen-bonding interactions of amide groups and π-π stacking interactions. The UV/Vis absorption spectrum of the homodimeric structure in the solid-state resulted in a broad Soret band. Time-dependent density functional theory (TD-DFT) calculation of the dimer indicated that an intra- and intermolecular charge transfer transition as well as a π-π* transition were responsible for the observed broad Soret band.

We demonstrate here that DNA-binding small molecules stabilize hairpin structures formed in short tandem repeat sequences, leading to efficient contractions of repeats during in vitro DNA synthesis. Repeat contraction by synthetic small molecules shows a repeat-number and sequence selective manner.

We investigate the response speed of thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) brushes by in situ electrical monitoring, which are grafted by surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP) on a gate electrode of a field-effect transistor (FET). A PNIPAAm brush shows the slow-phase-transition behavior for 5–6 h after a temperature rise or fall past a lower critical solution temperature. The PNIPAAm brush is constrained at the gate surface; therefore, the degree of freedom of a network bond is different along the film thickness. The polymer brush surface in direct contact with an electrolyte solution forms a skin layer, which makes the diffusion rate low.

We investigated the synthesis of poly(carbon sulfide) by electroreductive polymerization of CS₂. For example, a polymer was obtained in 10% yield as a black solid consisting of both crystal and amorphous states by constant potential electrolytic reduction in acetonitrile solution of Bu₄NBF₄. Its electrical conductivity after doping with iodine was 1.7 × 10⁻² S/m. By contrast, electrical conductivity of that prepared with Bu₄NPF₆ was 7.2 × 10⁻⁴ S/m. This difference is discussed by results of IR spectroscopic, elemental, XRD analyses.

Local charge carrier dynamics in diketopyrrolopyrrole (DPP)-tetrabenzoporphyrin (BP)-based bulk heterojunction (BHJ) films are investigated by optical pump-terahertz probe spectroscopy. Here we focus on the effect of the alkyl chain lengths of DPP on the carrier dynamics. In contrast to the large difference in the power conversion efficiency, similar dynamics are observed between C10-DPP-BP and C4-DPP-BP BHJ films. We discuss the origin of similarity in terms of nature of the high frequency response of photo-generated charge carriers.

A spectrally narrow band edge emission is generated in the green region from cadmium-free quantum dots comprised of silver indium gallium sulfide coated by gallium sulfide shells. The thickness of the gallium sulfide shell is increased by using gallium tris(diethyldithiocarbamate) as a supplementary precursor showing a strong adhesion with the quantum dot cores. Photoluminescence intensity and spectral shape of the core/shell quantum dots with the thicker shells are unchanged after 90 days.

Antibody mimetics are proteins smaller than antibodies that have antigen-binding properties. Here, we used a combination of informatic selection and experimental verification to identify from a public database several candidate scaffold proteins. From those candidates, we selected a protein with high thermal stability, bacterial expression, and mutation tolerance and used molecular engineering and phage display selection techniques to develop the scaffold into an antibody mimetic with binding affinity for galactin-3, a biomarker of cancer and heart disease.

Ag nanoparticle (NP)-incorporated AgI has been formed in the pores of TiO₂ nanocrystalline film (Ag@AgI/mp-TiO₂) by a successive ionic layer adsorption and reaction-photoreduction method. Ag@AgI/mp-TiO₂ stably shows visible-light activity for the degradation of 2-naphthol used as a model hydrosphere pollutant. Photoelectrochemical measurements indicated that the photocatalytic activity stems from the interband transition of AgI with it greatly enhanced by the localized surface plasmon resonance excitation of the Ag NPs.

Amphiphilic diarylethene with tri(ethylene glycol) chains as a hydrophilic moiety and octylcarbamoyl chain as a hydrophobic moiety formed a supramolecular assembly by hydrophobic interactions in water. The closed-ring isomer formed bunched vesicles made of strongly curled bilayers. When methylcellulose was added to the suspension, sheets with a width of several hundred micrometers were mainly obtained by depletion force. The obtained sheets retained photoinduced shrinking character.

A novel hypercrosslinked polymer (HCP) was prepared via Friedel-Crafts alkylation reaction of Schiff base with benzene and formaldehyde dimethyl acetal (FDA) promoted by FeCl₃. The HCP was then metalated with Pd(II) to form heterogeneous catalyst. The protocol featured low cost, mild conditions, readily available materials, easy separation and high yield. Physicochemical methods, including IR, N₂ sorption, ICP, TGA, XPS, SEM, EDX, and TEM, were used to characterize the catalyst structure and composition. The results reveal that the heterogeneous catalyst possesses high specific surface area, large pore volume, good chemical and thermal stability, and highly dispersed palladium. The heterogeneous catalysts were applied in Suzuki-Miyaura coupling reaction to evaluate their catalytic performance. The experiments reflected that the HCPs-Pd(OAc)₂ was an efficient catalyst for Suzuki-Miyaura reactions with the yield of biaryl up to 99%, while the TON could reach 2250. The reusability test showed the catalyst was easily recovered and reused for at least six times without obvious decrease in activity.

A novel rigid macrocyclic ligand based on the bis(pyridylimino)isoindole framework bearing the disulfide moiety was designed and synthesized to investigate the behavior of the disulfide in mononuclear transition metal complexes. Intrinsically high reactivity of the Co(II) disulfide complex was clearly found by observation of the progress of the ring-contraction reaction to form a thioether complex in the presence of cyclooctene. On the other hand, the Fe(II) disulfide complex was found to be stable even when heated at 60 °C under the same conditions. This difference in reactivity of disulfide complexes might be derived from the difference in the ionic radii of Co(II) and Fe(II); when the smaller Co(II) ion was installed into the disulfide-bearing macrocyclic ligand, the structural demand for square pyramidal geometry around the Co center drove ring-contraction, eliminating a sulfur atom from the strained disulfide complex.

A set of electronic-structure informatics (ESI) descriptors was applied to classify modes of toxic action (MoA) of 245 phenol derivatives to the growth of Tetrahymena pyriformis. The extreme gradient boosting classification (XGBC) method was performed for classification where the synthetic minority oversampling technique (SMOTE) was employed to overcome the imbalance in the MoA classification data available in the literature. Performance evaluation of the machine learning procedure shows that it is able to classify the molecular set into the five MoA classes. The feature importance analysis suggests electronic factors determining characteristics for each MoA class.

Since the development of imidazo[1,5-a]pyridinylidenes (imidazo[1,5-a]pyridine carbenes: IPCs) by Lassaletta, Alcarazo, and Glorius, these have been applied as ligands in catalysts, albeit that only few productive examples have been reported so far. Nevertheless, some productive IPC catalytic systems have recently been developed by several research groups, including ours. In the present account, our recent advances regarding the use of IPC ligands in catalysis are summarized, with a particular focus on the relationship between their catalytic activity and their electronic and steric features.

Hydrogenation reactions using non-fossil-based hydrogen sources upgrade ubiquitous molecules to useful chemicals with low environmental load and can be promoted on nanoscale inorganic catalysts (nanocatalysts). This review discusses determining factors that enhance the catalytic activity and selectivity of thermal and electrochemical hydrogenation reactions using nanocatalysts, of which the reactivity is dependent on their electronic states, atomic arrangements and surface structures.

We demonstrate that a dipole-dipole interaction of benzo[c][1,2,5]thiadiazole moieties, directional H-bond formation of carboxy groups, and a rigid molecular skeleton enable a structurally-predictable two-dimensional hydrogen-bonded organic framework BTIA-1 from tetratopic carboxylic acid. Activated form BTIA-1a was revealed to have BET surface area of 237 m²g⁻¹ and show selective adsorption of CO₂.

Helicenes are attractive non-planar polycyclic aromatic hydrocarbons with unique optical and electronic properties. In recent years, the chemistry of “multiple helicenes” with plural helicities in a single molecule has also grown rapidly as a research area due to intriguing properties such as highly distorted structures, multidimensional intermolecular interactions, and enhanced chiroptical properties. In this review, we summarize the synthesis and the molecular structures of multiple helicenes. Taking into consideration that the applied π-conjugated framework largely affects their synthesis, molecular structures, and physical properties, we categorize them according to the central π-conjugated core from smaller to larger aromatic rings and not the criterion of the original classification of multiple helicenes (multiplicity and the number of fused rings). Furthermore, we cover structural parameters and aromaticity of multiple helicenes, especially for the individual benzene rings, based on the definition of “twisting angle” and NICS values, respectively.

VT transition from the high-spin Co^II to low-spin Co^III state was observed for complex (N-cyclo-hexyl-2-iminopyridine)(3,6-di-tert-butyl-o-benzosemiquinonato)(3,6-di-tert-butyl-catecholato)cobalt in both solid and liquid form. For the first time we demonstrate a low-temperature nanosecond pump-probe XANES experiment revealing the valence tautomeric transition in a solution of Co complex. Reversible transition was induced both under the temperature and laser radiation stimuli.

Today, people are exposed to a wide variety of different airborne pollutants such as PM_2.5 and pollen. It is expected that novel materials will be developed to avoid their adhesion. The roughness at the interface is very important for the adhesion between such pollutants and a substrate. In this study, we have focused on self-assembling fibers formed from an amphiphilic peptide, palmitoyl-glycine-histidine (Pal-GH). The self-assembled fibers of Pal-GH formed a rough membrane and showed very effective anti-pollution effects against pollen and PM_2.5.