Fabrication of mesoporous Pt nanotubes utilizing dual templates under a reduced pressure condition

Pt nanotubes with mesoporous walls have been successfully prepared for the first time by the combination of hard templates (porous anodic alumina membranes, PAAM) and soft templates (lyotropic liquid crystals, LLC).     

Decelerated chirality interconversion of an optically inactive 3(10)-helical peptide by metal chelation

A dynamically optically inactive 3(10)-helical peptide possessing metal chelating ability between the side-chains at the i and i + 3th residues was synthesized, and its metal complexes were shown to stabilize the peptide structure and the helical sense.     

Gold-catalyzed intermolecular addition of alcohols toward the allenic bond of 4-vinylidene-2-oxazolidinones

Gold catalyzed intermolecular addition of alcohols toward the proximal allenic double bond of 4-vinylidene-2-oxazolidinones gives hydroalkoxylation products, which can be easily converted into the corresponding novel spiro dihydrofuran or dihydropyran derivatives in high yield.     

On the mechano-chiral effect of vortical flows on the dichroic spectra of 5-phenyl-10,15,20-tris(4-sulfonatophenyl)porphyrin J-aggregates

Phase-modulated ellipsometry of the J-aggregates of the title porphyrin shows that the material gives a true CD signal. This confirms that there is a real chiral transfer by mechanical forces, mediated by shear gradient flows, from the macroscopic to the electronic transition level. Dislocations in the structure of the aggregate could justify the formation of chirality at the level of the electronic transitions once the mesophases can be sculptured by hydrodynamic gradient flows.     

A simple and rapid CZE method for the analysis of mycophenolic acid and its phenol glucuronide metabolite in human serum

A simple and rapid capillary electrophoretic method was developed for simultaneous determination of mycophenolic acid and its metabolite, phenol glucuronide, in human serum. The sample preparation in the proposed method required only the precipitation by acetonitrile. Separation was performed by capillary zone electrophoresis using 75 mM phosphate buffer (pH 7.5) as running buffer, an applied voltage of 10 kV, and UV detection at 217 nm. Each serum sample analysis was completed within 15 min. The optimized method demonstrated good performance concerning specificity, linearity (r>0.9955), accuracy (95.9-113%), precision (<6.4%) and enough sensitivity for therapeutic drug monitoring. This method was successfully applied to measurements of mycophenolic acid and mycophenolic acid glucuronide in renal transplant patient samples and was a useful alternative to high-performance liquid chromatography-based methods.     

Synthesis and structure of polyunsaturated [10]paracyclophane annulated by two azulene rings

The polyunsaturated [10]cyclophane 4 was synthesized from 1,4-diacetylbenzene by a four-step sequence involving the modified Yasunami azulene synthesis, introduction of two butenone units, and a subsequent McMurry coupling reaction. The crystal structures of 4 and the synthetic intermediate 8 was determined by X-ray crystallographic analysis and the results reveal that (1) the benzene ring of 4 is distorted as a boat form with relatively small bending angles and (2) the azulene rings of 8 show large out-of-plane deformation along the short azulene molecular axis.     

Spiro[1H-azulenium-1,9′-fluorene] perchlorate. Intramolecular charge-transfer interaction between orthogonally arranged units of the azulenium cation and fluorene

Spiro[1H-azulenium-1,9′-fluorene] (3) perchlorate was synthesized in five steps starting from fluorenone and trimethylsilyl enol ether of 1-acetylcycloheptatriene. The pK_R+ value of 3 was determined to be 7.8. A characteristic absorption band of 3 in acetonitrile was observed at 430 nm, which shows a bathochromic shift in dichloromethane, indicating the first example of the intramolecular charge-transfer interaction between orthogonally arranged units of an azulenium ion having a tropylium ion ring and fluorene having two benzene rings.     

High-performance thin-layer chromatography/mass spectrometry for rapid analysis of neutral glycosphingolipids

Direct coupling of high-performance thin-layer chromatography (HPTLC) to matrix-assisted laser desorption/ionization quadrupole ion trap time-of-flight mass spectrometry (MS) was shown to be a reliable and reproducible method to obtain structural information and fundamental properties of glycosphingolipids (GSLs). We report a protocol for the preparation of neutral GSL extracts from mouse tissues and demonstrate the applicability of HPTLC/MS to these preparations. The protocol consists of lipid extraction and ion exchange chromatography followed by a mild alkaline treatment and a reversed-phase cartridge extraction. Possible structures for each GSL are proposed based on HPTLC/MS analyses. This fast and simple method can be used to screen neutral GSL extracts obtained from tissues and cells without isolation and purification into individual GSLs.     

Single-laboratory validation of a method for the determination of c-phycocyanin and allophycocyanin in Spirulina (Arthrospira) supplements and raw materials by spectrophotometry

A single-laboratory validation study was conducted for a 2-wavelength spectrophotometric method for the determination of c-phycocyanin (cPC) and allophycocyanin (aPC) in Spirulina supplements and raw materials. The absorption maxima of cPC and aPC are at 620 and 650 nm, respectively. The concentrations of the analytes were calculated from measurement of absorbance at 2 wavelengths. This method provided linear responses for cPC and aPC in the range of 25-250 microg/mL. Duplicate determinations of cPC and aPC in 4 different test materials on 5 different days resulted in relative standard deviations of 0.3-1.0 and 1.0-1.5% for cPC and aPC, respectively. Recoveries were 99.2-102.4 and 100.0-104.0% for cPC and aPC, respectively. The results were satisfactory for the determination of cPC and aPC in Spirulina supplements.     

Mean-field derivation of the interacting boson model Hamiltonian and exotic nuclei

A novel way of determining the Hamiltonian of the interacting boson model (IBM) is proposed. Based on the fact that the potential energy surface of the mean-field model, e.g., the Skyrme model, can be simulated by that of the IBM, parameters of the IBM Hamiltonian are obtained. By this method, the multifermion dynamics of surface deformation can be mapped, in a good approximation, onto a boson system. The validity of this process is examined for Sm and Ba isotopes, and an application is presented to an unexplored territory of the nuclear chart, namely, the right lower corner of 208Pb.