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Studies on charge transport (CT) in a Nafion film incorporating [(NH3)5Ru(mu-pz)Ru(NH3)5]4+([RuII-RuII]4+; pz=pyrazine) using a double potential-step chronoabsorptometry (DPSCA) technique is reported. The predominant CTs by a physical displacement mechanism of the complexes was found for each step, however the rate constant of the CT for the first step was found to be 5.2 times higher than that for the second step at 25 degree.

The synthesis of di and tri(1,2-phenyleneethynylene)s with phenoxyl radicals at the 4 position is described. A ferromagnetic coupling effect was observed between the diphenyl ethynylene bridge and the phenoxyls.

Nitroxide diradicals are compounded and characterized using X-ray crystallography, magnetic resonance spectroscopy, and magnetic studies in solution and in solid state.

A purely organic, high-spin and durable polyradical molecule is synthesized. It is based on the non-Kekule- and non-disjoint design of a pi-conjugated poly(1,2-phenylenevinylene) backbone pendantly 4-substituted with multiple robust arylaminium radicals.

Nitroxide diradicals, in which nitroxides are annelated to m-phenylene forming tricyclic benzo-bisoxazine-like structures, have been synthesized and characterized by X-ray crystallography, magnetic resonance (EPR and ¹H NMR) spectroscopy, as well as magnetic studies in solution and in solid state. For the octamethyl derivative of benzobisoxazine nitroxide diradical, the conformationally constrained nitroxide moieties are coplanar with the m-phenylene, leading to large values of 2J (2 J/k > 200 K in solution and 2 J/k ⪢ 300 K in the solid state). For the diradical, in which all ortho and para positions of the m-phenylene are sterically shielded, distortion of the nitroxide moieties from coplanarity is moderate, such that the singlet-triplet gaps remain large in both solution (2 J/k > 200 K) and the solid state (2J/k ≈ 400-800 K), though an onset of thermal depopulation of the triplet ground state is detectable near room temperature. These diradicals have robust triplet ground states with strong ferromagnetic coupling and good stability at ambient conditions. Magnetic behavior of the nitroxide diradicals at low temperature is best fit to the model of one-dimensional S = 1 Heisenberg chains with intrachain antiferromagnetic coupling. The antiferromagnetic coupling between the S = 1 diradicals may be associated with the methyl nitroxide C-H⋯O contacts, including nonclassical hydrogen bonds. These unprecedented organic S = 1 antiferromagnetic chains are highly isotropic, compared to those of the extensively studied Ni(II)-based chains. [ABSTRACT FROM AUTHOR]

We previously developed IM-54 as a novel type of inhibitor of hydrogen-peroxide-induced necrotic cell death. Here, we examined its cell death inhibition profile. IM-54 was found to selectively inhibit oxidative stress-induced necrosis, but it did not inhibit apoptosis induced by various anticancer drugs or Fas ligand, or necroptosis. IM-17 , an IM derivative having improved water-solubility and metabolic stability, was developed and confirmed to retain necrosis-inhibitory activity. IM-17 showed cardioprotective effects in an isolated rat heart model and an in vivo arrhythmia model, suggesting that IM derivatives may have therapeutic potential., Competing Interests: The authors declare no competing financial interest.

Blue phases (BPs) have received considerable attention as light shutters in the next generation of liquid crystal (LC) displays. However, no simple and efficient chiral dopant for induction of BPs of commercially available rodlike LC compounds has been reported. In this study, both (R) and (S) forms of novel chiral dopants were synthesized, showed extremely high helical twisting power values in nematic LC compounds, and induced stable BPs with a small amount of our chiral dopants (3-5 mol %). In enantiomeric excess controlled experiments, we found novel phenomena in their physical properties, such as generation of a metastable chiral nematic phase between an isotropic state and a BP.

A series of crocetin glycosides (crocins) are the main pigment of the stigmas of saffron (Crocussativus L.) and the fruits of gardenia (Gardenia jasminoides Ellis). Although numerous studies have demonstrated that crocetin and crocins have a variety of biological functions, the metabolism of dietary crocetin and crocins remains unknown. In the present study, we investigated the intestinal absorption of orally administered crocetin and crocins in mice. Orally administered crocetin was rapidly absorbed into the blood circulation and was present in plasma as an intact free form and as glucuronide conjugates (crocetin-monoglucuronide and -diglucuronide). Crocetin and its glucuronide conjugates were also found in crocins-administered mouse plasma, whereas intact crocins (glycoside forms) were not detected. These results indicate that orally administered crocins are hydrolyzed to crocetin before or during intestinal absorption, and absorbed crocetin is partly metabolized to mono- and diglucuronide conjugates.