A novel sphingosine with osteoclast-forming suppressing activity,from the edible mushroom Grifola gargal

A novel sphingosine, 1,2-diacetylsphingosine (1), was isolated from the edible mushroom Grifola gargal. The structure of 1 was determined by the interpretation of spectroscopic data. Compound 1 suppressed the formation of osteoclast without toxicity.     

Template effect in the competition between Haeckelite and graphene growth on Ni(111): quantum chemical molecular dynamics simulations

Quantum chemical molecular dynamics (QM/MD) simulations of ensembles of C(2) molecules on the Ni(111) terrace show that, in the absence of a hexagonal template or step edge, Haeckelite is preferentially nucleated over graphene as a metastable intermediate. The nucleation process is dominated by the swift transition of long carbon chains toward a fully connected sp(2) carbon network. Starting from a pentagon as nucleus, pentagons and heptagons condense during ring collapse reactions, which results in zero overall curvature. To the contrary, in the presence of a coronene-like C(24) template, hexagonal ring formation is clearly promoted, in agreement with recent suggestions from experiments. In the absence of step edges or molecular templates, graphene nucleation follows Ostwald's "rule of stages" cascade of metastable states, from linear carbon chains, via Haeckelite islands that finally anneal to graphene.     

Synthesis of a wide range of thioethers by indium triiodide catalyzed direct coupling between alkyl acetates and thiosilanes

An indium triiodide-catalyzed substitution of the acetoxy group in alkyl acetates with thiosilanes provides access to a variety of thioethers. The method is efficient for a wide scope of acetates such as primary alkyl, secondary alkyl, tertiary alkyl, allylic, benzylic, and propargylic acetates.     

In operando X-ray absorption fine structure studies of polyoxometalate molecular cluster batteries: polyoxometalates as electron sponges

We carried out in operando Mo K-edge X-ray absorption fine structure measurements on the rechargeable molecular cluster batteries (MCBs) of polyoxometalates (POMs), in which a Keggin-type POM, [PMo(12)O(40)](3-), is utilized as a cathode active material with a lithium metal anode. The POM-MCBs exhibit a large capacity of ca. 270 (A h)/kg in a voltage range between V = 4.0 V and V = 1.5 V. X-ray absorption near-edge structure analyses demonstrate that all 12 Mo(6+) ions in [PMo(12)O(40)](3-) are reduced to Mo(4+) in the discharging process. This means the formation of a super-reduced state of the POM, namely, [PMo(12)O(40)](27-), which stores 24 electrons, and this electron number can explain the large capacity of the POM-MCBs. Furthermore, extended X-ray absorption fine structure analyses reveal the molecular structure of [PMo(12)O(40)](27-), which is slightly reduced in size compared to the original [PMo(12)O(40)](3-) and involves Mo(4+) metal-metal-bonded triangles. Density functional theory calculations suggest that these triangles are formed because of the large number of additional electrons in the super-reduced state.     

A fluorous synthetic receptor that recognizes perfluorooctanoic acid (PFOA) via fluorous interaction obtained by molecular imprinting

A polymeric sorbent selective for perfluorooctanoic acid (PFOA) was synthesized by a molecular imprinting technique using a fluorous monomer and cross-linker, and assessed chromatographically, suggesting that the fluorous imprinted polymer recognizes PFOA via hydrogen bonding and fluorine-fluorine interaction.     

Focusing properties of vector vortex beams emitted by photonic-crystal lasers

We experimentally investigate the focusing properties of first- and second-order vector beams and vector vortex beams generated by photonic-crystal lasers. When the azimuthal indices of the vector beam (l) and the phase dependence (n) match, strong intensity appears at the center of focus. Our theoretical analyses agree well with the experimental results and predict that the central intensity has circular polarization.     

TG-DTA/GC-MS study of odorless woodceramics from chicken wastes

Summary An odorless woodceramics (CH800), which was prepared by carbonizing chicken wastes with phenolic resin, was characterized by XRD and thermal analysis. CH800 was found to consist mainly of amorphous carbon (non-graphitizing carbon) as studied by XRD. Differing from carbonized chicken waste, CH800 was completely free of unfavorable smell. The source of strong smell of carbonized chicken waste was studied by using TG-DTA combined with EGA technique using gas chromatography and mass spectrometry (TG-DTA/GC-MS). As a result, it was found that CH800 was completely free of compounds having strong smell, i.e., ethanol, acetonitrile, pyridine, styrene, benzonitrile and benzofuran, whereas carbonized chicken waste contained all of these compounds.     

One-electron reductive template-directed ligation of oligodeoxynucleotides possessing a disulfide bond

Hypoxic X-radiolysis of diluted aqueous solutions was performed to generate hydrated electrons that induced one-electron reduction of oligodeoxynucleotides (ODNs) possessing a disulfide bond. Upon hypoxic irradiation of dinucleotides, two forms of dinucleotides were produced via intermolecular exchange of the disulfides and ligation that proceeded with a multiple turnover. In contrast to the efficient reaction induced by hypoxic irradiation, the reaction efficiency was dramatically decreased when irradiation was performed under aerobic conditions, presumably due to capturing reactive hydrated electrons by molecular oxygen. We subsequently applied these unique reaction characteristics to template-directed ligation. In the presence of a complementary template ODN, two ODNs possessing a disulfide bond produced a prescribed ODN with high regioselectivity via interstrand crossing upon hypoxic irradiation.     

Three novel oligosaccharides synthesized using Thermoanaerobacter brockii kojibiose phosphorylase

Background  

Recently synthesized novel oligosaccharides have been produced primarily by hydrolases and glycosyltransferases, while phosphorylases have also been subject of few studies. Indeed, phosphorylases are expected to give good results via their reversible reaction. The purpose of this study was to synthesis other novel oligosaccharides using kojibiose phosphorylase.     

Lusternik–Schnirelmann category of non-simply connected compact simple Lie groups

Let FX→B be a fibre bundle with structure group G, where B is (d−1)-connected and of finite dimension, d1. We prove that the strong L–S category of X is less than or equal to , if F has a cone decomposition of length m under a compatibility condition with the action of G on F. This gives a consistent prospect to determine the L–S category of non-simply connected Lie groups. For example, we obtain cat(PU(n))3(n−1) for all n1, which might be best possible, since we have cat(PU(p^r))=3(p^r−1) for any prime p and r1. Similarly, we obtain the L–S category of SO(n) for n9 and PO(8). We remark that all the above Lie groups satisfy the Ganea conjecture on L–S category.