Benzyl radical addition reaction through the homolytic cleavage of a benzylic C-H bond

Direct generation of a benzyl radical by C-H bond activation of toluenes and the addition reaction of the resulting radical to an electron deficient olefin were developed. The reaction of dimethyl fumarate with toluene in the presence of Et(3)B as a radical initiator at reflux afforded 2-benzylsuccinic acid dimethyl ester in good yield.     

A complementary organic inverter of porphyrazine thin films: low-voltage operation using ionic liquid gate dielectrics

We studied a complementary organic inverter consisting of a p-type semiconductor, metal-free phthalocyanine (H(2)Pc), and an n-type semiconductor, tetrakis(thiadiazole)porphyrazine (H(2)TTDPz), operated through the ionic-liquid gate dielectrics of N,N-diethyl-N-methyl(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)imide (DEME-TFSI). This organic inverter exhibits high performance with a very low operation voltage below 1.0 V and a dynamic response up to 20 Hz.     

Electronic spectra of the jet-cooled 1-methylvinylthio radical

Electronic spectra of the B?-X? transition of the 1-methylvinylthio radical were observed in a discharged jet of propylene sulfide by laser-induced fluorescence spectroscopy. Identification of the spectral carrier was made by comparing the observed spectra with results of molecular orbital calculations, in particular, for vibrational frequencies, rotational contour simulations, and the Franck-Condon simulations. Vibrational structures observed in the electronic spectra indicate that the 1-methylvinylthio radical can be regarded as a molecule with C(s) symmetry at the zero-point levels of both the excited and ground states.     

Specific Binding of Anionic Porphyrin and Phthalocyanine to the G-Quadruplex with a Variety of <em>i</em><em>n Vitro</em> and<em> </em><em>i</em><em>n Vivo</em> Applications

The G-quadruplex, a four-stranded DNA structure with stacked guanine tetrads (G-quartets), has recently been attracting attention because of its critical roles in vitro and in vivo. In particular, the G-quadruplex functions as ligands for metal ions and aptamers for various molecules. Interestingly, the G-quadruplex can show peroxidase-like activity with an anionic porphyrin, iron (III) protoporphyrin IX (hemin). Importantly, hemin binds to G-quadruplexes with high selectivity over single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA), which is attributable to an electrostatic repulsion of phosphate groups in ssDNA and dsDNA. The G-quadruplex and hemin-G-quadruplex complex allow development of sensing techniques to detect DNA, metal ions and proteins. In addition to hemin, anionic phthalocyanines also bind to the G-quadruplex formed by human telomere DNA, specifically over ssDNA and dsDNA. Since the binding of anionic phthalocyanines to the G-quadruplex causes an inhibition of telomerase activity, which plays a role in the immortal growth of cancer cells, anionic phthalocyanines are promising as novel anticancer drug candidates. This review focuses on the specific binding of hemin and anionic phthalocyanines to G-quadruplexes and the applications in vitro and in vivo of this binding property.     

Whole-body distribution of <Superscript>14</Superscript>C-labeled silica nanoparticles and submicron particles after intravenous injection into Mice

We analyzed the whole-body distribution of ¹⁴C–ADP-labeled silica nanoparticles (¹⁴C–ADP–SiO₂ nanoparticles) and submicron particles (¹⁴C–ADP–SiO₂ submicron particles) after intravenous injection into ICR mice. The ¹⁴C–ADP–SiO₂ nanoparticles and submicron particles were synthesized before the injection and the particle size was 19.6 and 130 nm, respectively. Similarly, the shape was spherical and the crystallinity was amorphous. After the synthesis, we injected mice with the ¹⁴C–ADP–SiO₂ nanoparticles or the ¹⁴C–ADP–SiO₂ submicron particles and dissected tissues after 1, 2, 4, 8 and 24 h. The radioactivity in the tissues was measured with a liquid scintillation counter. As a result, the retention percentage in bone, skin, lymph nodes, and the digestive mixture was at least twofold higher in the ¹⁴C–ADP–SiO₂ nanoparticles-exposed mice, whereas the retention percentage in the kidney was statistically higher in the ¹⁴C–ADP–SiO₂ submicron particles-exposed mice. Both types of ¹⁴C–ADP–SiO₂ particles mainly translocated to the muscle, bone, skin, and liver, but hardly translocated to the brain and olfactory bulb. Furthermore, the ¹⁴C–ADP–SiO₂ nanoparticles had a higher retention percentage (62.4 %) in the entire body at 24-h post-injection than did the ¹⁴C–ADP–SiO₂ submicron particles (50.7 %). Therefore, we suggested that the ¹⁴C–ADP–SiO₂ nanoparticles might be more likely than the ¹⁴C–ADP–SiO₂ submicron particles to be retained in the body, and consequently they might be gradually accumulated by chronic exposure.     

Observation and control of transverse energy-transport barrier due to the formation of an energetic-electron layer with sheared ExB flow

Off-axis electron-cyclotron heating in an axisymmetric barrier mirror produces a cylindrical layer with energetic electrons, which flow through the central cell and into the end region. The layer, producing a localized bumped ambipolar potential Phi(C), forms a strong shear of radial electric fields E(r) and peaked vorticity with the direction reversal of E(r)xB sheared flow near the Phi(C) peak. Intermittent vortexlike turbulent structures near the layer are suppressed in the central cell by this actively produced transverse energy-transport barrier; this results in T(e) and T(i) rises surrounded by the layer.     

The Core Fucose on an IgG Antibody is an Endogenous Ligand of Dectin‐1

The core fucose, a major modification of N‐glycans, is implicated in immune regulation, such as the attenuation of the antibody‐dependent cell‐mediated cytotoxicity of antibody drugs and the inhibition of anti‐tumor responses via the promotion of PD‐1 expression on T cells. Although the core fucose regulates many biological processes, no core fucose recognition molecule has been identified in mammals. Herein, we report that Dectin‐1, a known anti‐β‐glucan lectin, recognizes the core fucose on IgG antibodies. A combination of biophysical experiments further suggested that Dectin‐1 recognizes aromatic amino acids adjacent to the N‐terminal asparagine at the glycosylation site as well as the core fucose. Thus, Dectin‐1 appears to be the first lectin‐like molecule involved in the heterovalent and specific recognition of characteristic N‐glycans on antibodies.