Herein, we demonstrate that the dimerization behavior of amine-substituted dicyanomethyl radicals can be switched from σ- to π-dimerization simply by varying the electron-donating substituents. For dicyanomethyl radicals with a 4,4'-ditolylamine (DT ) or a phenothiazine (PT ) substituent, the monomeric radical form and the corresponding dimer connected by a reversible C-C bond (σ-dimer) are in equilibrium in solution. On the other hand, the radical with the julolidine skeleton (JD ) does not undergo σ-dimerization and was isolated as a stable radical in spite of the absence of bulky protecting groups. X-ray single-crystal analysis revealed that JD forms the π-dimer in the crystalline state, and variable-temperature spectroscopy showed that JD is in equilibrium with the π-dimer in toluene solution. DFT calculations point to the importance of electrostatic interactions as a driving force for the π-dimerization of JD because of its polarized structure.

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Good results can be expected from placement of Gianturco stents except when CT shows the obstruction to be totally enveloped by tumor.

Electron-rich cycloparaphenyleneacetylenes as well as their twin "glasses-like" conjugates form stable complexes with fullerenes.

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The tetramers of azapentacene derivatives with unique hash mark (#)-shaped structures were prepared in a quite facile manner. The #-shaped tetramers are optically active due to possessing extended biaryl skeletons, and the structure of the tetramer composed of four dihydrodiazapentacene (DHDAP) units (1) was investigated as the first example of this kind of molecule. The tetramer 1 showed characteristic chiroptical properties reflecting its orthogonally arranged quadruple DHDAP moieties, as well as redox activity. The solution of enantiopure 1 exhibited intense circularly polarized luminescence (CPL) with a dissymmetry factor of 2.5 × 10. The absolute configuration of the enantiomers of 1 was experimentally determined by X-ray crystal analysis for the dication salt of the enantiomer of 1 with SbCl counterions. The solutions of enantiopure 1·2[SbCl] also showed NIR circular dichroism (CD) spectra over the entire range from visible to 1100 nm, enabling the modulation of the chiroptical properties by redox stimuli.

Recently, it has been clarified that glutamate (Glu) can stimulate the umami taste as well as the visceral sensation to help the gastric protein digestion. Our survey suggests the possibility that the amount of free Glu in hospital foods is lower than that in ordinary foods. In the present study, monosodium glutamate (MSG) was supplemented to meals for 11 elderly inpatients during 2 months, and the fortification effects on their nutritional status, general condition, and quality of life (QOL) were investigated. The degree of recognition was improved, and peripheral lymphocytes were increased, even when there was no change in nutritional intake or protein nutritional status. Based on these results, we concluded that appropriate utilization of Glu for nutritional care of the elderly people would be useful for improving QOL.

Herein, we demonstrate that the dimerization behavior of amine‐substituted dicyanomethyl radicals can be switched from σ‐ to π‐dimerization simply by varying the electron‐donating substituents. For dicyanomethyl radicals with a 4,4′‐ditolylamine (DT.) or a phenothiazine (PT.) substituent, the monomeric radical form and the corresponding dimer connected by a reversible C−C bond (σ‐dimer) are in equilibrium in solution. On the other hand, the radical with the julolidine skeleton (JD.) does not undergo σ‐dimerization and was isolated as a stable radical in spite of the absence of bulky protecting groups. X‐ray single‐crystal analysis revealed that JD. forms the π‐dimer in the crystalline state, and variable‐temperature spectroscopy showed that JD. is in equilibrium with the π‐dimer in toluene solution. DFT calculations point to the importance of electrostatic interactions as a driving force for the π‐dimerization of JD. because of its polarized structure.