A Reaction of Triazoles with Thioesters to Produce β‐Sulfanyl Enamides by Insertion of an Enamine Moiety into the Sulfur–Carbonyl Bond

N‐Sulfonyl‐1,2,3‐triazoles react with thioesters in the presence of a rhodium(II) catalyst to produce β‐sulfanyl enamides in a stereoselective manner. The reaction proceeds through generation of an α‐imino rhodium carbene complex, nucleophilic addition of the sulfur atom of a thioester onto the carbenoid carbon atom, and subsequent intramolecular migration of the acyl group from the sulfur atom to the imino nitrogen atom. The method is successfully applied to a ring‐expansion reaction of thiolactones, thus leading to the formation of sulfur‐containing lactams.     

A Simplified Neuronal Model for the Instigation and Propagation of Cortical Spreading Depression

In this paper, we construct a simplified neuronal model that is capable of simulating the instigation of cortical spreading depression (CSD) and propagation of a CSD wave. Our model is a simplification and extension of a single neuron model proposed in the literature for studying the instigation of CSD. Using the simplified neuronal model, we construct a network of these simplified neurons. This network model shows that the propagation of a CSD wave occurs naturally after it is instigated electrically or chemically. Although the model is simple, the speed of the CSD wave predicted by our model is consistent with experimentally observed values. Finally, our model allows us to investigate the effects of specific ion channels on the spread of a CSD wave.     

l‐Kynureninium sulfate dihydrate

In the structure of the title compound, 2‐(3‐ammonio‐3‐carboxy­propanoyl)‐1‐anilinium sulfate dihydrate, C₁₀H₁₄N₂O₃²⁺·SO₄^2?·2H₂O, the two amino groups are proton­ated. The mol­ecule has a trans planar zigzag carbon‐skeletal conformation elongated nearly in the benzene ring plane. The two amino and the carboxyl groups are located on the same side of the mol­ecule. The crystal structure is stabilized by intermolecular hydrogen bonds involving the water mol­ecules and the sulfate ion.     

Path integral hybrid Monte Carlo calculation of the bosonic oscillators

In this paper, various correlation functions for a bosonic many-body system have been calculated using the path integral hybrid Monte Carlo method proposed by the authors [Chem. Phys. Lett. 308, 115 (1999)]. A system consisting of 32 independent particles in a harmonic well was chosen as a model problem. Calculations were carried out at two temperatures for the Boltzmann and Bose statistics. The large amplitude of the bosonic pair-correlation function around origin was found in comparison with the boltzmannoniac counterpart. This behavior can be interpreted by effective “attractive interaction” between particles arising from the Bose statistics.     

Mössbauer spectroscopy of133Cs following the decay of133Xe atoms implanted in metals

Mössbauer effect measurements for the 81 keV transition in¹³³Cs have been performed with¹³³Xe-implanted sources prepared by means of an electromagnetic isotope separator. The behavior of the isomer shift of¹³³Cs impurities was studied in various metals. Some correlations were found between measured isomer shifts and electronic properties of the host materials, and they show that the host conduction electrons have an important role in the determination of the isomer shift in metals.     

Aerosol-size distribution of radon daughter218Po in the accelerator tunnel air

Aerosol-size distributions of²¹⁸Po were determined for the accelerator tunnel air sampled during machine operation and for the basement air of a concrete building, where the number and the size distribution of non-radioactive aerosols are greatly different from each other. The²¹⁸Po distributions depended very much on the size distributions of ambient non-radioactive aerosols, and could be well explained by an attachment model of²¹⁸Po to ambient non-radioactive aerosols.     

Precision synthesis of (1→6)-α-D-glucopyranan by cationic ring-opening polymerization of 1,6-anhydro-2,3,4-tri-O-allyl-β-D-glucopyranose

The ring-opening polymerization of 1,6-anhydro-2,3,4-tri-O-allyl-β-D-glucopyranose ( 2 ) has been carried out using various cationic initiators. For the condition of [ 2 ]/[BF₃·OEt₂] = 20 at −15°C for 90 h, the polymer yield, M_w and M_w/M_n of the polymer obtained were 79%, 215,600 and 3.45, respectively. In order to study the living characteristic of the polymerization of 2 , the cationic ring-opening bulk polymerization initiated by trimethylsilyl trifluoromethanesulfonate (TMSOTf) was carried out under the condition of [ 2 ]/[TMSOTf] = 1000 at −15 °C. The M_w value increased in proportion to conversion until c.a. 30% and below. The M_w/M_ns of resulting polymers were very narrow, e.g., the M_w/M_n value was 1.2 and below, which was smaller than that for the solution polymerization using BF₃·OEt₂. These results indicated that the ring-opening bulk polymerization of 2 using TMSOTf was living-like.     

Chiral Macrocycles Having C3 Symmetry Resulting from Orientation of Thiophene Rings

An chiral Rh^II-catalyzed cyclooligomerization reaction of thiophenes having triazolyl and vinyl substituents at the 2- and 4-positions was studied. Structurally interesting cyclic trimers, having chirality that is ascribed only to the orientation of the 2,4-disubstituted thiophene rings, are obtained. The 2,4-disubstitution of the starting thiophene monomer allows production of each of the enantiomers. The observed electronic circular-dichroism spectra are in accord with those simulated by density-functional theory calculations.     

Paraoxonase 1 and Non-Alcoholic Fatty Liver Disease: A Meta-Analysis

Oxidative stress is involved in the pathophysiology of nonalcoholic fatty liver disease (NAFLD). However, reliable biomarkers of NAFLD in relation to oxidative stress are not available. While paraoxonase 1 (PON1) is an antioxidant biomarker, there appears to be mixed data on PON-1 in patients with NAFLD. The aim of this meta-analysis was to assess the current data on PON1 activity (i.e., paraoxonase and arylesterase) in patients with NAFLD. A PubMed, CENTRAL, and Embase search identified 12 eligible articles. In the meta-analysis, the paraoxonase activity was low in patients with NAFLD (mean difference (MD) −27.17 U/L; 95% confidence interval (CI) −37.31 to −17.03). No difference was noted in the arylesterase activity (MD 2.45 U/L; 95% CI −39.83 to 44.74). In a subgroup analysis, the paraoxonase activity was low in biopsy-proven nonalcoholic steatohepatitis (MD −92.11 U/L; 95% CI −115.11 to −69.11), while the activity in NAFLD as diagnosed by ultrasonography or laboratory data was similar (MD −2.91 U/L; 95% CI −11.63 to 5.80) to that of non-NAFLD. In summary, the PON1, especially paraoxonase, activity could be a useful biomarker of NAFLD. Further studies are warranted to ascertain the relevance of PON1 measurements in patients with NAFLD.