Synthesis of lyoniresinol with combined utilization of synthetic chemistry and biotechnological methods

We have synthesized lyoniresinol with the combined utilization of synthetic chemistry and biotechnological methods, specifically using plant cell cultures as an "enzyme source."     

Possibility of isostructural condensed states of matter in the D phase of ANBC and the cubic mesophase of BABH: heat capacity of 4'-n-octadecyloxy-3'-nitrobiphenyl-4-carboxlic acid, ANBC(18)

Heat capacity measurements have been made on ANBC(18) at temperatures from 8 to 490 K by adiabatic calorimetry. All known phases were detected. The temperatures, enthalpies and entropies of transition were determined for the phase transitions observed. On the basis of the entropy of transition to the SmC phase from the D or cubic phases, it is pointed out that the D phase of ANBC and the cubic phase of BABH might be identical in nature. It is shown that the arrangement of 'molecular' cores has a higher degree of order in the isotropic (D and cubic) phases than in the SmC phase, whereas the terminal alkoxy chains are more disordered in the isotropic phases than in the SmC phase. The degrees of disorder in the D and cubic phases relative to the SmC phase are very similar in terms of the entropy of transition per methylene group. The inverted phase sequence in ANBC (SmC D on heating) and BABH (cubic SmC) can be accounted for in terms of the competing roles in the entropy between the molecular core and the chains.     

Tetracyanoethylene oxide not only oxidizes sulfides to sulfoxides but also reduces sulfoxides to sulfides

It was found that tetracyanoethylene oxide not only oxidizes sulfides to sulfoxides but also reduces sulfoxides to sulfides with generation of two molecules of carbonyl cyanide. The reaction thus also functions as a new method for generation of carbonyl cyanide.     

Synthesis of allenes from allylic alcohol derivatives bearing a bromine atom using a palladium(0)/diethylzinc system

A general and efficient synthesis of allenes using a palladium(0)/diethylzinc system is described. Treatment of mesylates or trichloroacetates of (E)- or (Z)-2-bromoalk-2-en-1-ols with diethylzinc in the presence of a catalytic amount of palladium(0) affords allenes bearing an aminoalkyl, alkyl, or aryl substituent(s) in good to high yields. No transfer of chirality from the stereogenic center carrying the mesyloxy group to the allene was observed.     

Novel bifunctional probe for radioisotope-free photoaffinity labeling: compact structure comprised of photospecific ligand ligation and detectable tag anchoring units

A novel method for radioisotope-free photoaffinity labeling was developed, in which a bifunctional ligand is connected to a target protein by activation of a photoreactive group, such as an aromatic azido or 3-trifluoromethyl-3H-diazirin-3-yl group, and identification of the ligated product is achieved by anchoring of a detectable tag through the Staudinger-Bertozzi reaction with an alkyl azido moiety that survives photolysis. The chemical ground of this method was confirmed using model compounds with the bifunctional group under photoirradiation in the presence of trapping agents for reactive intermediates. The utility of the method has been demonstrated by specific labeling of the catalytic portion of human HMG-CoA reductase.     

Stereodivergent synthesis of the 2,3,5,6-tetrasubstituted piperidine ring system: an application to the synthesis of alkaloids 223A and 205B from poison frogs

Stereodivergent synthesis of the 2,3,5,6-tetrasubstituted piperidine ring system has been achieved by sequential stereocontrolled Michael-type conjugate addition reaction of appropriate enaminoesters. This methodology has been applied to the total syntheses of the poison frog alkaloids 223A and 205B. The relative stereochemistry of natural 223A at the 6-position was revised, and the absolute stereochemistry of natural 205B was determined by the present synthesis.     

Dielectric analysis of sheep erythrocyte ghost. Examination of applicability of dielectric mixture equations

The purpose of this study is to confirm the applicability of dielectric mixture equations in dielectric analysis of biological cell suspensions. Two dielectric mixture equations, the Pauly-Schwan (P-S) equation and the Hanai-Asami-Koizumi (H-A-K) equation were tested using sheep erythrocyte ghosts whose internal solution is identical with the external solution. Dielectric measurements were carried out for the ghost suspensions over a frequency range 10 kHz to 100 MHz; a single dielectric relaxation was found between 100 kHz and 10 MHz. From the dielectric relaxation, the conductivity and permittivity of the ghost interior and the capacitance of the cell membrane were calculated following the P-S and H-A-K equations. When the H-A-K equation was employed (and as expected from the property of the ghosts), the estimated internal conductivity was in good agreement with the external conductivity at volume fractions up to about 0.7. With the P-S equation, on the other hand, the same results as above were obtained but only at low volume fractions below about 0.3. In addition, the H-A-K equation provided a better simulation for the observed relaxation curves than did the P-S equation, especially at high volume fractions. It is, therefore, concluded that the H-A-K equation is applicable to a wider range of volume fraction than is the P-S equation.     

Polymer analysis using pyrolysis-GC-FTIR-MS and GC-AED

Volatile pyrolysates of a methyl methacrylate-butadiene-styrene copolymer (MBS) have been analyzed using a capillary gas chromatograph equipped with a Fourier transform infrared detector in tandem with a mass selective detector, and a gas chromatograph-atomic emission detector system. Among the volatile compounds observed were monomers used for synthesis of the polymer. Numerous oligomers of higher boiling point were also found; identification of these could be used to give structural information about the parent polymer. Combining information from these techniques was found to be extremely useful for the analysis of polymer pyrolysis products. In characterizing each compound it was found particularly helpful to juxtapose feature-specific chromatograms (e.g., single ion monitoring from the mass-selective detector and the selected wavelength chromatography from the infrared detector).