A Ni0(cod)(dq) (COD: 1,5-cycloctadiene; DQ: duroquinone) complex as a catalyst precursor for oligothiophene and polythiophene synthesis.

Nickel-catalyzed syntheses of oligothiophene and polythiophene were carried out with Ni(cod)(dq) (COD: 1,5-cycloctadiene; DQ: duroquinone) as a catalyst precursor. Studies on the ligand exchange of Ni(cod)(dq) revealed that a high temperature was necessary to replace COD and DQ with PPh3 and N-heterocyclic carbene IPr. A coupling reaction of a metalated 3-hexylthiophene with 2-chloro-3-hexylthiophene employing Ni(cod)(dq) with IPr proceeded with a remarkably reduced amount of homocoupling byproduct. Polymerization of 2-chloro-3-hexylthiophene with Ni(cod)(dq)/DPPP also resulted in the reduction of the regioregularity defect.

Synthesis of Chiral α-Substituted ß-Aminophosphine Derivatives through Asymmetric Hydrophosphinylation Utilizing Secondary Phosphine Sulfides.

The organocatalytic enantioselective hydrophosphinylation of various secondary phosphine sulfides with aromatic and aliphatic nitroalkenes is presented in this study. The reaction produced chiral ß-nitrophosphine sulfides with excellent yields and enantioselectivities (up to 99% yield and 99% ee). Furthermore, the chiral ß-nitrophosphine sulfides can be easily converted into α-substituted ß-aminophosphine, which is a family of useful P, N-ligands and phosphine catalysts.

Ultra-Fine Bubble Distributions in a Plant Factory Observed by Transmission Electron Microscope with a Freeze-Fracture Replica Technique.

Water containing ultra-fine bubbles (UFB) may promote plant growth. But, as UFBs are too small to distinguish from other impurities in a nutrient solution, it is not known if UFBs survive transport from the water source to the rhizosphere. Here we use the freeze-fracture replica method and a transmission electron microscope (TEM) to observe UFBs in the nutrient solutions used in a crop-growing system known as a plant factory. In this factory, TEM images taken from various points in the supply line indicate that the concentration of UFBs in the nutrient solution is conserved, starting from their addition to the nutrient solution in the buffer tank, through the peat-moss layer, all the way to the rhizosphere. Measurements also show that a thin film formed on the surface of UFBs in the nutrient solution, with greater film thickness at the rhizosphere. This film is considered to be made from the accumulation of impurities coming from solute and the peat-moss layer.

Reconstitution of amoeboid motility in vitro identifies a motor-independent mechanism for cell body retraction.

Crawling movement in eukaryotic cells requires coordination of leading-edge protrusion with cell body retraction [1-3]. Protrusion is driven by actin polymerization along the leading edge [4]. The mechanism of retraction is less clear; myosin contractility may be involved in some cells [5] but is not essential in others [6-9]. In Ascaris sperm, protrusion and retraction are powered by the major sperm protein (MSP) motility system instead of the conventional actin apparatus [10, 11]. These cells lack motor proteins [12] and so are well suited to explore motor-independent mechanisms of retraction. We reconstituted protrusion and retraction simultaneously in MSP filament meshworks, called fibers, that assemble behind plasma membrane-derived vesicles. Retraction is triggered by depolymerization of complete filaments in the rear of the fiber [13]. The surviving filaments reorganize to maintain their packing density. By packing fewer filaments into a smaller volume, the depolymerizing network shrinks and thereby generates sufficient force to move an attached load. Our work provides direct evidence for motor-independent retraction in the reconstituted MSP motility system of nematode sperm. This mechanism could also apply to actin-based cells and may explain reports of cells that crawl even when their myosin activity is compromised.

Rapid and quantitative imaging of excitation polarized fluorescence reveals ordered septin dynamics in live yeast.

We report an imaging method for fast, sensitive analysis of the orientation of fluorescent molecules by employing a liquid-crystal based universal polarizer in the optical path of a wide-field light microscope. We developed specific acquisition and processing algorithms for measuring the anisotropy and for correcting artifacts caused by fluorescence bleaching, background light, and differential transmission of optical components. We call this approach the Fluorescence LC-PolScope and we used it to analyze the architectural dynamics of septin-green fluorescent protein (septin-GFP) constructs in the neck region of budding yeast. We describe three different states of highly anisotropic septin arrays in which the prevailing orientation of GFP dipoles was either parallel or perpendicular to the mother-bud axis. The transitions between these ordered states were characterized by transient isotropic states. To analyze the patterns of polarized fluorescence, we modeled the alignment of septin-GFP constructs in different stages of septin ring formation. Based on our model, our experimental data are consistent with the formation of paired rather than single filaments and the axis of the α-helical septin terminus linked to a GFP molecule is likely oriented normal to the cell surface. The Fluorescence LC-PolScope combines the molecular specificity of fluorescence tagging with the structural specificity of polarized light analysis.

Assembly of the fluorescent acrosomal matrix and its fate in fertilization in the water strider, Aquarius remigis.

Animal sperm show remarkable diversity in both morphology and molecular composition. Here we provide the first report of intense intrinsic fluorescence in an animal sperm. The sperm from a semi-aquatic insect, the water strider, Aquarius remigis, contains an intrinsically fluorescent molecule with properties consistent with those of flavin adenine dinucleotide (FAD), which appears first in the acrosomal vesicle of round spermatids and persists in the acrosome throughout spermiogenesis. Fluorescence recovery after photobleaching reveals that the fluorescent molecule exhibits unrestricted mobility in the acrosomal vesicle of round spermatids but is completely immobile in the acrosome of mature sperm. Fluorescence polarization microscopy shows a net alignment of the fluorescent molecules in the acrosome of the mature sperm but not in the acrosomal vesicle of round spermatids. These results suggest that acrosomal molecules are rearranged in the elongating acrosome and FAD is incorporated into the acrosomal matrix during its formation. Further, we followed the fate of the acrosomal matrix in fertilization utilizing the intrinsic fluorescence. The fluorescent acrosomal matrix was observed inside the fertilized egg and remained structurally intact even after gastrulation started. This observation suggests that FAD is not released from the acrosomal matrix during the fertilization process or early development and supports an idea that FAD is involved in the formation of the acrosomal matrix. The intrinsic fluorescence of the A. remigis acrosome will be a useful marker for following spermatogenesis and fertilization.

The absolute configurations of hydroxy fatty acids from the royal jelly of honeybees (Apis mellifera).

9-Hydroxy-2E-decenoic acid (9-HDA) is a precursor of the queen-produced substance, 9-oxo-2E-decenoic acid (9-ODA), which has various important functions and roles for caste maintenance in honeybee colonies (Apis mellifera). 9-HDA in royal jelly is considered to be a metabolite of 9-ODA produced by worker bees, and it is fed back to the queen who then transforms it into 9-ODA. Recently we found that 9-HDA is present in royal jelly as a mixture of optical isomers (R:S, 2:1). The finding leads us to suspect that chiral fatty acids in royal jelly are precursors of semiochemicals. Rather than looking for semiochemicals in the mandibular glands of the queen bee, this study involves the search for precursors of pheromones from large quantities of royal jelly. Seven chiral hydroxy fatty acids, 9,10-dihydroxy-2E-decenoic, 4,10-dihydroxy-2E-decenoic, 4,9-dihydroxy-2E-decenoic, 3-hydroxydecanoic, 3,9-dihydroxydecanoic, 3,11-dihydroxydodecanoic, and 3,10-dihydroxydecanoic acids were isolated. The absolute configurations of these acids were determined using the modified Mosher's method, and it was revealed that, similar to 9-HDA, five acids are present in royal jelly as mixtures of optical isomers.

Acylated glycosides of hydroxy fatty acid methyl esters generated from the crude resin glycoside (pharbitin) of seeds of Pharbitis nil by treatment with indium(III) chloride in methanol.

Treatment of the crude ether-insoluble resin glycoside (convolvulin) from seeds of Pharbitis nil (Pharbitis Semen), called pharbitin, with indium(III) chloride in methanol provided seven oligoglycosides of hydroxy fatty acid methyl esters partially acylated by 2-methyl-3-hydroxybutyric (nilic) and 2S-methylbutyric acids. Their structures were elucidated on the basis of NMR and MS data and chemical conversions.

Components of ether-insoluble resin glycoside (convolvulin) from seeds of Quamoclit pennata.

Alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction of the seeds of Quamoclit pennata BOJER (Convolvulaceae) provided five new glycosidic acids, quamoclinic acids B, C, D, E, and F, along with six organic acids, isobutyric, 2S-methylbutyric, tiglic, 2R,3R-nilic, 7S-hydroxydecanoic, and 7S-hydroxydodecanoic acids. These new compounds were characterized on the basis of spectroscopic data as well as chemical evidence. Quamoclinic acids E and F are the first examples of heptaglycosides of glycosidic acid.

Novel cycloartane-type triterpenoid from the fruits of Nandina domestica.

A novel cycloartane-type triterpenoid was isolated from the fruits of Nandina domestica (Berberidaceae). The structure was characterized as 24-methylene-3-oxocycloartane 13-carboxylic acid on the basis of NMR spectroscopic data.

The resin glycosides from the sweet potato (Ipomoea batatas L. LAM.).

Four new and two known ether-soluble resin glycosides were isolated from popular sweet potato (the roots of Ipomoea batatas L. LAM., Kokei 14 go, Convolvulaceae) in Japan. Unlike ester-type dimers, batatins I and II, obtained from other sweet potato (Ipomoea batabas var. batatas), the glycosides were tetra or pentasaccharide monomers in which the sugar moieties are partially acylated by organic acids and combine with the aglycone, jalapinolic acid, to form a macrocyclic ester.

A new microscope optics for laser dark-field illumination applied to high precision two dimensional measurement of specimen displacement.

With conventional light microscopy, precision in the measurement of the displacement of a specimen depends on the signal-to-noise ratio when we measure the light intensity of magnified images. This implies that, for the improvement of precision, getting brighter images and reducing background light noise are both inevitably required. For this purpose, we developed a new optics for laser dark-field illumination. For the microscopy, we used a laser beam and a pair of axicons (conical lenses) to get an optimal condition for dark-field observations. The optics was applied to measuring two dimensional microbead displacements with subnanometer precision. The bandwidth of our detection system overall was 10 kHz. Over most of this bandwidth, the observed noise level was as small as 0.1 nm/radicalHz.

Compositions of royal jelly II. Organic acid glycosides and sterols of the royal jelly of honeybees (Apis mellifera).

Two organic acid glycosides (1, 2) and 16 sterols were isolated from the royal jelly of honeybees (Apis mellifera). The former two were monoglucosides of 10-hydroxy-2E-decenoic and 10-hydroxydecanoic acids. They are the first examples of glycosides isolated from royal jelly. The latter 16 were sterols mainly composed of 28 or 29 carbons. Among them, four compounds were new isofucosterol derivatives, and their structures were characterized as (24Z)-stigmasta-5,24(28)-dien-3beta-ol-7-one (3), (24Z)-stigmasta-5,24(28)-diene-3beta,7beta-diol (4), (24Z)-stigmasta-5,24(28)-diene-3beta,7alpha-diol (5), and (24Z)-stigmast-24(28)-ene-3beta,5alpha,6beta-triol (6) on the basis of various NMR spectroscopic data.

Cantharimide dimers from the Chinese blister beetle, Mylabris phalerate PALLAS.

Five cantharidin-related compounds were isolated from the Chinese blister beetle, Mylabris phalerate PALLAS (Meloidae). Their structures were determined based on spectroscopic and chemical evidence. Three of them were identified as cantharimide dimers, which consist of two units of cantharimide combined with a tri-, tetra-, or penta-methylene group.

Two isoindoline alkaloids from the crude drug, the ant lion (the larvae of Myrmeleontidae species).

Two compounds having an isoindoline skeleton were isolated from the ant lion (the larvae of Myrmeleontidae species). They were characterized as 4-hydroxyisoindolin-1-one and 2-(2-hydroxyethyl)-4-hydroxyisoindolin-1-one on the basis of spectroscopic data.

Isolation and characterization of some hydroxy fatty and phosphoric acid esters of 10-hydroxy-2-decenoic acid from the royal jelly of honeybees (Apis mellifera).

The present work characterizes novel FA in the royal jelly of honeybees (Apis mellifera). TLC analysis showed that the chloroform/methanol extract obtained from royal jelly consists mainly of FA. The FABMS spectrum of this extract gave several ion peaks due to compounds with higher M.W. than those of the FA so far reported. The methanol extract was found to contain unknown phospholipids. By means of reversed-phase HPLC with various solvent systems, 13 compounds were obtained in pure state. Their structures including absolute configurations were determined by chemical, NMR, and MS spectral analysis. Six compounds were identified as novel mono- or di-esters of 10-hydroxy-2E-decenoic acid in which the hydroxyl group was esterified by another FA unit, and one was hydroxy-2E-decenoic acid 10-phosphate. In addition, we demonstrated that 9-hydroxy-2E-decenoic acid exists as a mixture of optical isomers.

Fluctuation of actin sliding over myosin thick filaments in vitro.

It is customarily thought that myosin motors act as independent force-generators in both isotonic unloaded shortening as well as isometric contraction of muscle. We tested this assumption regarding unloaded shortening, by analyzing the fluctuation of the actin sliding movement over long native thick filaments from molluscan smooth muscle in vitro. This analysis is based on the prediction that the effective diffusion coefficient of actin, a measure of the fluctuation, is proportional to the inverse of the number of myosin motors generating the sliding movement of an actin filament, hence proportional to the inverse of the actin length, when the actions of the motors are stochastic and statistically independent. Contrary to this prediction, we found the effective diffusion coefficient to be virtually independent of, and thus not proportional to, the inverse of the actin length. This result shows that the myosin motors are not independent force-generators when generating the continuous sliding movement of actin in vitro and that the sliding motion is a macroscopic manifestation of the cooperative actions of the microscopic ensemble motors.

Three novel cantharidin-related compounds from the Chinese blister beetle, Mylabris phalerata Pall.

Three novel cantharidin analogues were isolated from the Chinese blister beetle, Mylabris phalerata PALL. (Meloidae), which has been used in traditional Chinese medicine for the treatment of cancer. Their structures were determined on the basis of heteronuclear multiple-bond connectivity and nuclear Overhauser effect spectroscopy experiments, and chemical data confirmed them to be so-called cantharimides, in which the anhydride oxygen atoms are replaced by the basic amino acid L-lysine, L-ornithine, and L-arginine moieties.