Creation of a mixed-valence state from one-dimensionally aligned TTF utilizing the self-assembling nature of a low molecular-weight gel

One-dimensional TTF assemblies have been obtained through the design of low molecular-weight gels, which show a characteristic absorption band at around 1750 nm upon I2 doping, assignable to a mixed-valence state of the TTF assemblies.     

Coenzyme models. 15. A polymeric model system for the NADH-dependent dehydrogenase enzymes

Copolymers of 4-vinylpyridine (4-VP) and N-(p-vinylbenzyl)-1,4-dihydronicotinamide (VNicH) were synthesized, and a carbonyl substrate (benzil) was reduced to alcohol in an aqueous ethanol solution in the absence and presence of metal ions (Zn²⁺ and Ni²⁺) as part of a model study of NADH-dependent enzymes. The reduction rates by VNicH in polymers were four to seven times greater than that of the corresponding monomeric analog (N-benzyl-1,4-dihydronicotinamide). Added metal ions catalyzed the reduction by VNicH-29 (VNicH content, 29 mole%) but inhibited the reduction by VNicH-9 (VNicH content, 9 mole%). It was suggested that metal catalysis occurs only when metal ions are bound closely near the dihydronicotinamide moiety.     

Synthesis and optical resolution of a new flavin with axial chirality and redox-dependent racemization

A new flavin (3-methyl-10-(2′-phenyl)phenylisoalloxazine) with restricted rotation about the C(1′)?N(10) single bond was synthesized and optically resoluted for the first time. (+)- Isomer (100% enantiomeric purity) did not racemize at ambient conditions, whereas it racemized invariably when it was reduced (by four different methods). The kinetic studies proved that the novel racemization mode is attributed to conversion of the “planar” oxidized form to the “bent” reduced form.     

Beta-1,3-glucan (schizophyllan) can act as a one-dimensional host for creation of novel poly(aniline) nanofiber structures

We here demonstrate the creation of novel poly(aniline) (PANI) nanofiber structures by a polymer wrapping method using schizophyllan (SPG). Mannose-modified SPG can also wrap PANIs to give nanofibers having a lectin affinity. This interaction is applicable to designing novel PANI/protein composites. The results establish that SPG can act as a novel "host" to assemble PANIs into one-dimensional superstructures. [reaction: see text]     

Face-selective decoration of an organic single crystal toward photochemical devices

Face-selective decoration of a single crystal constructed from 1-pyrenemethylammonium chloride by an anionic porphyrin dye is reported. CLSM observations indicated that the {001} face of the single crystal was selectively coated by the anionic porphyrin (TPPS). This novel achievement could be the first step for preparation of multi-component composite materials mediated by anisotropy of organic single crystals toward photochemical devices.     

Olefin metathesis of the aligned assemblies of conjugated polymers constructed through supramolecular bundling

The ordered structures constructed from an aligner molecule 1o and conjugated polymers (CPs) were efficiently converted into the poly-pseudo-rotaxane structures by the template-assisted ring-closing olefin metathesis (RCM) of olefinic groups at the peripheral positions of 1o. Moreover, the poly-pseudo-rotaxane structures permitted the separation of the crystalline ordered assemblies of CP by size exclusion chromatography and the preservation of the sheet morphologies after the treatment with trifluoroacetic acid. The morphologies and the periodicities of assemblies were also maintained after the retrieving treatments.     

Highly enantioselective recognition of dicarboxylic acid substrates by the control of nonlinear responses

An allosteric host, in which the molecular information of the chiral guest was precisely introduced, exhibits unconventional enantioselectivity toward the target enantiomer even under the conditions of a -20% enantiomeric excess (ee) mixture within a certain concentration window. This is effected by incorporation of the structural information of the enantiomer into the host and the utilization of multiple equilibrium.