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.     

An algebraic proof of the cyclic sum formula for multiple zeta values

We introduce an algebraic formulation of the cyclic sum formulas for multiple zeta values and for multiple zeta-star values. We also present an algebraic proof of cyclic sum formulas for multiple zeta values and for multiple zeta-star values by reducing them to Kawashima's relation.     

Determination of the liver cytosolic proteins that bind to p-hydroxyacetophenone

The purpose of the present study was to determine the proteins that bind to acetophenones in the liver. Immobilized p-hydroxyacetophenone (p-HAP) was used as a ligand of affinity chromatography. Analysis using sodium dodesyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that five polypeptides in the liver cytosolic fraction specifically bound to the p-HAP matrix. These polypeptides were digested with Lys-specific protease and used to generate peptide maps by reversed-phase high-performance liquid chromatography. Consequently, identification from a data base of protein sequences revealed that the five polypeptides were glycogen phosphorylase, cytosolic aldehyde dehydrogenase, adenosine kinase, class I alcohol dehydrogenase and glutathione S-transferase A2. In addition to p-HAP, acetylsalicylic acid also displayed a prominent ability to elute these five enzymes from the p-HAP affinity column loaded with the cytosolic fraction of the liver. Thus, p-HAP has affinities to the above liver enzymes and is a useful ligand for analysis of them.     

The effect of delta lambda chirality on molecular organization in two-dimensional films of a Ru(II) complex with a mesogenic ligand

A novel amphiphilic Ru(II) complex, [Ru(acac)2L] (acac = acetylacetonato, L = 5,5'-bis(4-octylphenyloxycarbonyl)-2,2'-bipyridyl), in which L undergoes SmC, SmA and N liquid crystal phases, exhibits a remarkable chirality effect on its monolayer state: that is, a racemic mixture gives a monolayer consisting of spike-like aggregates of 1.2 nm (in height) x 50 nm (in diameter), whereas the delta-enantiomer gives a uniform monolayer.     

Temperature dependence of oxygen reduction activity at Pt-Fe, Pt-Co, and Pt-Ni alloy electrodes

Oxygen reduction reaction (ORR) activity and H(2)O(2) formation at Pt(54)Fe(46), Pt(68)Co(32), and Pt(63)Ni(37) electrodes in 0.1 M HClO(4) solution at 20 to 90 degrees C were investigated by using a channel flow double electrode method. In the temperature range of 20-50 degrees C, the apparent rate constants k(app) for ORR at these electrodes were found to be 2.4-4.0 times larger than that at a pure Pt electrode, whereas their apparent activation energies of 41 kJ mol(-1) at -0.525 V vs E degrees (0.760 V vs RHE at 30 degrees C) were comparable to that at the Pt electrode. H(2)O(2) yield was ca. 1.0% at Pt(54)Fe(46) and ca. 0.16% at Pt(68)Co(32) and Pt(63)Ni(37) between 0.3 and 1.0 V vs RHE. The k(app) values at the alloy electrodes decreased with elevating temperature above 60 degrees C, and settled to almost the same values at the Pt electrode. The H(2)O(2) production was not detected at the alloy electrodes once heated at the high temperature in the solution, probably due to the thickening of the Pt skin-layer by a considerable dissolution of nonprecious metal components (Fe, Co, Ni) from the alloys.     

IR observation of adsorption and initial reactions of olefins on Brønsted acid sites of a deuterated ZSM-5

Adsorption of linear olefins (C₂?C₄) on a deuterated H-ZSM-5 (D-ZSM-5) was studied by infrared (IR) spectroscopy. The initial interaction of the olefins with Brønsted acidic OD groups was hydrogen-bonding to form π-complexes at low temperatures. The adsorbed ethene and propene desorbed by heating under evacuation, while various reactions took place for adsorbed 1-butene; double bond migration (DBM) to 2-butene below 230 K followed by dimerization at room temperature. An unusual reaction path was deduced for DBM of 1-butene, where proton transfer from Brønsted acid sites (BAS) to the adsorbed 1-butene was not essential.     

Formation of 3-Bromo-1,5- and −1,7-Azulenequinones from 1-Alkyl-and 1-Phenylazulenes by Substituent Extrusion on the Bromine- Oxidation in Aqueous THF. Remarkable Substituent Effects on the Product Distribution

Oxidation of 1-ethyl-, 1-propylazulenes, and their 5-isopropyl derivatives with bromine gave 3-bromo-1,5- and 3-bromo-l,7-azulenequinones (Type A) together with 3-bromo-l-hydroxy-5-isopropyl-l-alkylazulen-7-one and its isomeric products (Type B), while the same reaction of 1-methylazulenes afforded Type B products along with many unidentified products. On the other hand, 1-phenylazulene gave 3-phenyl-1,5- and 3-phenyl-l,7-azulenequinones (Type C) and Type B products in high yie]ds. 1,2-Polymethyleneazulenes afforded a considerable amount of 3-bromo-2-(ω-formylalkyl)azulenequinones together with Type B products. Possible pathways for the extrusion of the alkyl substituent at C-l are discussed.     

Gas chromatographic determination of m- and p-hydroxyphenytoin in the urine of epileptic patients

An analytical method for determining phenytoin and its metabolites in the urine of epileptic patients is described. The analysis was performed for the m- and p-isomers of hydroxyphenytoin, the oxidative products of phenytoin, using gas chromatography. As an internal standard, 5-(4-methylphenyl)-5-phenylhydantoin was chosen; the extraction solvent from human urine was ether-chloroform (3:7). Phenytoin and its hydroxy isomers were satisfactorily determined by the modified on-column methylation technique on a 2% OV-17 column using temperature programming from 180 degrees C to 240 degrees C at 5 degrees C/min.     

Stability and reproducibility of gel-suspension samples for the liquid scintillation counting of14C using N-lauroyl-L-glutamic-α,γ-dibutylamide

Stability and reproducibility of gel-suspension samples were investigated in order to evaluate the characteristic feature of the gel-suspension method for¹⁴C activity measurement. Commercially available gelling agent, N-lauroyl-L-glutamic-α,γ-dibutylamide, was used for the gelformatio of the samples. No change of the counting rate for the gel-suspension sample was observed for more than 2 years after the sample preparation. Four samples used for checking the reproducibility of the sample preparation method. The same values were obtained for the counting rate of¹⁴C activity within the counting error. No change of the counting rate was observed for the “re-gelated” sample. These results show that the gel-suspension method is appropriate for the¹⁴C activity measurement by the liquid scintillation method and is useful for a long-term preservation of the sample for repeated measurement.