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The existence of tetravalent dysprosium in perovskite-type oxide barium zirconate is confirmed in this work. This discovery will stimulate many researchers in diverse fields such as catalysts, solid state ionics, sensors, and fluorescent materials.

Chiral phosphine-prolineamide 1a was employed as an organocatalyst in direct asymmetric aldol reactions of various aromatic aldehydes with ketones. Cyclohexanone led to the aldol products in up to 98% ee and with good diastereoselectivity using 10 mol % of TFA and 30 mol % of prolineamide 1a in DMF at 0 °C.

The C3-vinyl group of chlorophyll derivative (I) is converted into an aldehyde by a novel one-pot reaction.

A new synthesis of 3(2H)-furanones from 4-hydroxy-2-alkyn-1-one derivatives via CO2 mediated bond reorganization has been developed to the preparation of an antitumor agent, geiparvarin and a constituent of flavors, 2,5-dimethyl-3(2H)-furanone.

Reactions of the kinetic enolates of 1-acetylcyclohexenes with α-bromo-α,β-unsaturated esters afford 5-methoxycarbonyltricyclo[4.4.0.01,5]decan-2-ones in one pot syntheses via successive Michael–Michael-substitution reactions.

The total synthesis of (+)-dysideapalaunic acid, a sesterterpenic aldose reductase inhibitor, has been accomplished. Starting from optically active(8aS)-(+)-3,4,8,8a-tetrahydro-5,8a-dimethylnaphthalene-1,6(2H,7H)-dione, (5S)-(–)-3,4,4a,5,6,7,8,8a-octahydro-5,8a-dimethyl-5-(4methylpent-3-enyl)naphthalen-1(2H)-one ethylene acetal has been synthesized in eight steps involving reductive allylation, deoxygenation, and a Wittig condensation. Transformation of this ethylene acetal via methylation at C-2, Grignard addition, and a Horner–Emmons reaction furnished the required (+)-acid in eight steps. Thus, the absolute stereochemistry of the (+)-acid has been established as (4aS,5S,8aS).

The chiral spiroaromatic compounds (+)-2 and (+)-3 with 9,9′-spirobifluorene skeletons have been synthesized and their absolute stereostructures have been unambiguously determined to be R, by application of the CD exciton chirality method; the R absolute stereochemistry of (–)-[6,6]-vespirene 1 was established by chemical correlation with these compounds.

Aldol condensation of the bistrimethylsilyl enol ether of methyl acetoacetate, compound 2, with 2-benzyloxyhexanal 3c affords highly selectively (99:1) the syn-aldol adduct 4c in the presence of titanium tetrachloride. The stereocontrolled synthesis of (–)-pestalotin 7 has been achieved.

Reaction of β-keto sulfoxides with trimethylsilyl trifluoromethanesulfonate in the presence of diisopropylethylamine afforded the corresponding (1E,3E)-1-phenylthio-2-(trimethylsilyloxy)-1,3-diene derivatives which underwent hydrolysis to furnish 1-phenylthio-alk-3-en-2-one derivatives in high yields.

The 8a R absolute stereochemistry of Wieland-Miescher ketone (-)- I was established by the X-ray structure analysis of its bis(4-bromobenzoate) derivatives (1 R ,6 R ,8a R )-(+)- IV and (1 R ,6 S ,8a R )-(-)- V . The absolute configuration of (-)- I was corroborated further by the application of the CD exciton chirality method to bis(4-bromobenzoates) (+)- IV and (-)- V .

The reaction of 3-(p-tolylsulfinyl)-2-butanone with trimethylsilyl trifluoromethanesulfonate in the presence of diisopropylethylamine gave 3-(p-tolylthio)-2-(trimethylsilyloxy)-1,3-butadiene (2) quantitatively. The Diels–Alder reactions of 2 and the related dienes with methyl acrylate were studied.

Reactions of the kinetic enolates 6 of 1-acetylcyclohexenes 5 with α-bromo α,β-unsaturated esters 7 proceed via a successive Michael–Michael-substitution pathway to give methyl 2-oxotricyclo[4.4.0.01,5]decane-5-carboxylates 8 in a one-pot operation.

An efficient preparative method for the enantiomerically pure juvenile hormone II has been developed by applying the diastereoselective alkylation and carbonyl reduction of an optically pure β-keto sulfoxide as the key steps.

Structural changes of the intermetallic compound Nb3Al before and after hydriding and dehydriding have been investigated by X-ray diffraction, electron microscopy and thermal analysis. A fine powder of this compound with an average particle size less than 14 μm can be easily prepared by hydriding at 773 K for 86.4 × 103 s and dehydriding at 1073 K for 10.8 × 103 s.

Condensation of 4-methyl-7-thiocoumarin sodium salt with methyl 5-N-acetyl-4, 7, 8, 9-tetra-O-acetyl-2-chloro-2, 3, 5-trideoxy-D-glycero-D-galacto-2-nonulopyranosonate (2), methyl 5-N-(O-acetylglycolyl)-4, 7, 8, 9-tetra-O-acetyl-2-chloro-2, 3, 6-trideoxy-D-glycero-D-galacto-2-nonulopyranosonate (11), and methyl 4, 5, 7, 8, 9-penta-O-acetyl-2-chloro-2, 3-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate (14) under Williamson reaction conditions gave the corresponding α-glycosides in good yields. Deprotection of these α-glycosides gave three new fluorogenic substrates, the 4-methylcoumarin-7-yl S-glycosides of N-acetylneuraminic acid, N-glycolylneuraminic acid, and 3-deoxy-D-glucose-D-galacto-2-nonulopyranosonic acid (KDN). Furthermore, we have developed a facile method for preparation of benzyl 5-amino-3, 5-dideoxy-α-D-glycero-D-galacto-2-nonulopyranosidonic acid (7), a key intermediate for the synthesis of N-glycolylneuraminic acid.

Enolate of Wieland-Miescher ketone 1 has reacted with methyl acrylate to give methyl (1S*,2S*,4R*,6S*)-6-methyltricyclo[6.2.2.0 1,6]-dodecan-7, 12-dion-2-carboxylate 5 whose structure has been determined by X-ray crystallography after transformation of 5 into sultamamide 8a.

S,S-Acetals are smoothly deprotected with air in the presence of a catalytic amount of bismuth (III) nitrate pentahydrate under ambient conditions to regenerate the original carbonyl compounds in good to excellent yields.

The disintegration due to hydrogenation of NbAl alloys with eight different compositions has been studied. The hydrogenation is performed directly in an arc-melting chamber without exposing NbAl ingots to air after arc-melting. Because the active surface resulting from arc-melting is preserved, NbAl alloys absorb a large amount of hydrogen and disintegrate rapidly into fine particles, even though the pressure of hydrogen is only at 0.1 MPa. This disintegration is closely related to the arc-melting atmosphere and the composition of the alloys. Structural changes of NbAl alloys before and after hydrogenation and dehydrogenation have been examined by X-ray diffraction, electron microscopy and chemical analysis. A fine powder of single Nb 3 Al phase with an average particle size of less than 14 μm can easily be obtained by hydriding NbAl alloy buttons with aluminum compositions from 22 to 28 at.% in an arc-melting chamber, followed by dehydrogenation at 1073 K for 3.6 ks.

Highly sensitive detection of morphine (MO) in ppb range was realized by using an immunosensor based on surface-plasmon-resonance (SPR) phenomena. The addition of MO into the antibody solution was found to reduce the incident angle shift of the SPR sensor system sharply because of the inhibition effect of MO. Based on this inhibiting principle, the present sensor could detect MO very sensitively in the concentration range of 0.1 - 10 ng/cm3 (ppb).

Highly enantioselective protonation of prochiral lithium enolates is disclosed. The present method employed ( S,R s )-CF 3 -hydroxy sulfoxide (3b) as the chiral protonating agent, and the protonation of lithium enolates of cyclohexanone derivatives with 3b proceeded with high enantioselectivities.

Bismuth bromide was found to work efficiently as a versatile catalyst for the cyanation and allylation of carbonyl compounds and acetals with organosilicon reagents, affording the corresponding alcohols and ethers in high yields.

Selective air oxidation of sulfides to sulfoxides was accomplished with a binary catalytic system, BiBr3-Bi(NO3)3, in high yields under aerial ambient conditions. This oxygenation requires neither an aldehyde nor a transition metal complex.

The phase relations in the system Dy–Mg–Cl at 1073 K have been established by isothermal equilibration and chemical analysis of quenched samples. Liquid Mg-rich alloy was found to be in equilibrium with molten DyCl2. Therefore, DyCl2 can be synthesized by reduction of MgCl2 with excess of metallic Dy at 1073 K. The Gibbs energy of formation of DyCl2 at 1073 K was evaluated by two different methods. From voltammetric determination of decomposition voltage, the upper limit for the standard Gibbs energy of formation of DyCl2 was estimated to be −505(±20) kJ mol−1. A value of −543(±10) kJ mol−1 was deduced from phase relations using Gibbs–Duhem integration. The value for the standard Gibbs energy of DyCl2 indicates that the Dy2+ ion has a potential capability for reducing TiCl4 to metal titanium. At the same time, Mg is a reductant for Dy3+ produced during the reduction of TiCl4. Thus, it is thermodynamically confirmed that reduction of TiCl4 by magnesium using a reaction mediator in the salt phase is feasible.

The standard Gibbs energies of formation of SrIrO3, Sr2IrO4 and Sr4IrO6 have been determined in the temperature range from 975 to 1400 K using solid-state cells with (Y2O3) ZrO2 as the electrolyte and pure oxygen gas at a pressure of 0.1 MPa as the reference electrode. For the design of appropriate working electrodes, phase relations in the ternary system Sr–Ir–O were investigated at 1350 K. The only stable oxide detected along the binary Ir–O was IrO2. Three ternary oxides, SrIrO3, Sr2IrO4 and Sr4IrO6, compositions of which fall on the join SrO–IrO2, were found to be stable. Each of the oxides coexisted with pure metal Ir. Therefore, three working electrodes were prepared consisting of mixtures of Ir+SrO+Sr4IrO6, Ir+Sr4IrO6+Sr2IrO4, and Ir+Sr2IrO4+SrIrO3. These mixtures unambiguously define unique oxygen chemical potentials under isothermal and isobaric conditions. Used for the measurements was a novel apparatus, in which a buffer electrode was introduced between reference and working electrodes to absorb the electrochemical flux of oxygen through the solid electrolyte. The buffer electrode prevented polarization of the measuring electrode and ensured accurate data. The standard Gibbs energies of formation of the compounds, obtained from the emf of the cells, can be represented by the following equations: View the MathML sourcem View the MathML source View the MathML source where Δf (ox)Go represents the standard Gibbs energy of formation of the ternary compound from its component binary oxides SrO and IrO2. Based on the thermodynamic information, chemical potential diagrams for the system Sr–Ir–O were developed.

A new C 2 -symmetric diphosphine ligand 8a was readily prepared in one step by treatment of the synthetic precursor of VALAP, 7 , with phthaloyl chloride. Remarkably high levels of asymmetric induction, over 99% ee, were achieved using 8a in palladium-catalyzed asymmetric allylic transformations of sterically less demanding cyclohexenyl substrates 9 . The ligand system was easily extended to the development of analogous chiral auxiliaries 8b , c by the identical procedure but using isophthaloyl chloride and succinyl chloride. However, the ligands 8b , c exhibited much lower catalytic activity. In contrast to the asymmetric allylic substitutions, 8c demonstrated significant improvement of enantioselectivity, up to 64% ee, in rhodium-catalyzed asymmetric hydrosilylations of acetophenone 11a compared to 35% ee using 8a . In this way, the versatility of the present ligand system played an important role in variations of substrates and reaction types.

Living organisms on the Earth which are divided into three major domains - Archaea, Bacteria, and Eucarya, probably came from a common ancestral cell. Because there are many thermophilic microorganisms near the root of the universal phylogenetic tree, the common ancestral cell should be considered to be a thermophilic microorganism. The existence of a cell is necessary for the living organisms; the cell membrane is the essential structural component of a cell, so its amphiphilic property is vital for the molecule of lipids for cell membranes. Tetraether type glycerophospholipids with C40 isoprenoid chains are major membrane lipids widely distributed in archaeal cells. Cyclization number of C40 isoprenoid chains in thermophilic archaea influences the fluidity of lipids whereas the number of carbons and degree of unsaturation in fatty acids do so in bacteria and eucarya. In addition to the cyclization of the tetraether lipids, covalent bonding of two C40 isoprenoid chains was found in hyperthermophiles. These characteristic structures of the lipids seem to contribute to their fundamental physiological roles in hyperthermophiles. Stereochemical differences between G-1-P archaeal lipids and G-3-P bacterial and eucaryal lipids might have occured by the function of some proteins long after the first cell was developed by the reactions of small organic molecules. We propose that the structure of lipids of the common ancestral cell may have been similar to those of hyperthermophilic archaea.

A partial pseudoternary phase diagram of the LaO1.5–BaO–ScO1.5 system was established at 1600 °C. According to the phase diagram, the solubility of barium into the cubic perovskite phase (LaScO3) at 1600 °C is 0.24 in a mole fraction of barium oxide (XBaO) on the composition line where the mole fraction of scandium oxide is 0.50. Another cubic perovskite phase (BaZrO3) in the BaO–ZrO2–ScO1.5 system is also known. We investigated the phase relationships between the two cubic perovskites in the pseudoquaternary phase diagram of the LaO1.5–BaO–ScO1.5–ZrO2 system. As a result, we found the existence of a wide solid solution region between the cubic perovskites at 1600 °C. The region was determined by X-ray diffraction (XRD) analysis and energy dispersive X-ray (EDX) microanalysis of samples with various compositions, and established the partial pseudoquaternary phase diagram.

Bridging parts X between two amide skeletons of C2-symmetric diphosphine ligands 1 were varied using various kinds of diacyl chlorides. The ligand 1c derived from phthaloyl chloride, which was remarkably effective in the asymmetric induction on palladium-catalyzed asymmetric allylic substitutions of 2-cyclohexenyl pivalate or acetate, exhibited a moderate level of enantioselectivity, 72% ee, in the transformations of 1,3-diphenyl-2-propenyl pivalate. The newly developed ligands 1g–i having one carbon spacers X demonstrated higher degrees of enantiomeric excess up to 93% ee. Interestingly, the present reactions catalyzed by Pd–1c–e,g–j complexes afforded the product 4 with the opposite absolute configuration S compared with the reactions using VALAP, which has the same chiral source as that of 1. The ligands 1a,b,f exhibited the induction of R configuration although the yields were very low. The production of S-4 was discussed on the basis of the Pr/Mr chirality model.

A series of novel nikkomycin analogue inhibitors of the chitin synthase of fungal cell wall was synthesized and evaluated for their inhibitory activities. Among them, the compound having a phenanthrene group at the terminal amino acid was found to possess strong anti-chitin synthase activity.