ChemInform Abstract: An Efficient Method for the Assembly of Sulfated Oligosaccharides Using Reductive Amination
ChemInform, May 26, 2010
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Side Chain Liquid Crystalline Polyoxetanes with a Spacer-Separated Azobenzene Moiety. Part 1. Preparation and Characterization
Polystyrene-polyoxetane composite resins were prepared via two-stage polymerizations using p-subs... more Polystyrene-polyoxetane composite resins were prepared via two-stage polymerizations using p-substituted styrenes CH2 =CHC6 HcO(CH 2).Br (7a or 7b), where n=4 or 6, and an isomeric mixture of m-and p-[3-(3-methyl-3-oxetanyl)-2-oxapropyl]styrenes (5) as a cross-linking agent. The terminal bromide linked to a styryl ring at the para position through an 1-oxapentamethylene spacer of7a (n = 4) was applicable to a starting substrate on polymer reactions with some nucleophiles, such as phenols, potassium acetate, and tributylamine, for obtaining polymeric derivatives via several reaction steps. These resins with a pendant quaternary ammonium bromide moiety were also used as phase-transfer catalysts. On the basis of their catalytic activities, qualities and spacer effects of these supporting resins were compared with those of resins obtained by using chloromethylstyrenes instead of 7a or divinylbenzenes instead of 5.
Evaluation of clustering effect of partial structure in heparin
Linker compound, ligand complex and methods for their preparation
Compose lieur, complexe ligand et procede pour leur production
Nouveau compose lieur qui minimise toutes les interactions hydrophobes non specifiques et qui est... more Nouveau compose lieur qui minimise toutes les interactions hydrophobes non specifiques et qui est capable de reguler aisement la longueur d'un groupe disulfure soumis a une liaison metallique pour ainsi permettre une formation suffisante d'une liaison metal-soufre ; nouveau complexe ligand ou substance porteuse de ligand ; et procede pour leur fabrication. Il est propose un compose lieur comprenant la structure de formule generale: (1) (dans laquelle chacun parmi a, b, d et e est independamment un entier de 0 a 6). Le X ci-dessus a l'extremite moleculaire a un groupe amino aromatique et au niveau de sa chaine principale a une structure de site structurel multibranche compose de 3 chaines hydrocarbonees ou plus ayant eventuellement des liaisons carbone-azote. Le complexe ligand se compose du compose lieur ci-dessus dans lequel on a introduit une molecule de sucre.
Compose de liaison polyvalent et ligand, procede de preparation de ces derniers
La presente invention concerne un compose de liaison presentant la structure representee par la f... more La presente invention concerne un compose de liaison presentant la structure representee par la formule (1) dans laquelle n represente un entier compris entre 1 et 6, et X presente une structure qui est un fragment de structure multi-segmentee comprenant trois ou quatre chaines hydrocarbone et un groupe amino aromatique a sa terminaison et qui peut contenir une liaison carbone-azote dans sa chaine principale; et un ligand qui comprend le compose de liaison et un saccharide introduit dans ce dernier. Formule (1)
Linker compound, ligand, and producing method thereof
Multipurpose linker compounds and ligands and process for producing the same
Versatile linker compound, ligand, and producing method thereof
Linker Compound, Ligand Complex and Process for Producing Them
Linker compound, ligand conjugate, and production methods thereof
Versatile linker compound and ligand, and method for preparation thereof
A generally applicable efficient method was developed for assembly of structurally defined sulfat... more A generally applicable efficient method was developed for assembly of structurally defined sulfated oligosaccharides. Using a reductive amination reaction at low pH with newly designed linkers possessing multiple aromatic amino groups, facile preparations of oligosaccharide assemblies were achieved without any alteration in the sulfated oligosaccharide parts.
All reactions in organic media were carried out with freshly distilled solvents or with commercia... more All reactions in organic media were carried out with freshly distilled solvents or with commercially available extra grade solvents purchased from Kanto Chem. Co. (Tokyo, Japan), Nacalai Tesque (Kyoto, Japan) or Wako Chem. Co. (Osaka, Japan). Silica gel column chromatography was performed using Silica gel 60, No. 9386, Merck & Co. Inc., Whitehouse Station, NJ, USA. Spectral Data were obtained as follows. ESI-TOF/MS spectra were obtained by Mariner TM (Applied Biosystems, Framingham, MA, USA). 1 H-NMR measurements were performed with JEOL (Tokyo, Japan) Lambda-500, GSX-400, and ECA-600. The chemical shifts are expressed in δ-values using tetramethylsilane (δ 0) or HDO (δ 4.65) as an internal standard. Synthesis of compounds Compound 2 : m-Phenylenediamine 1 (Nacalai Tesque, 0.50 g, 4.62 mmol) was dissolved in 35 ml of methanol, and di-t-butyl dicarbonate (Peptide Institute, Osaka, Japan, 1.06 ml, 4.62 mmol) and trietheylamine (Nacalai Tesque, 0.65 ml, 4.65 mmol) were added to the solution at 0 °C. The reaction solution was stirred for 24 h at room temperature. Then, the solution was concentrated with a rotary evaporator. The resultant residue was applied on a silicagel column (100 g, solvent: chloroform/acetone = 10/1, v/v) to obtain white powder. Yield: 665 mg (68%). MS calcd. for C 11 H 16 N 2 O 2 : 208.12, Found:
Highlights The controlled silylation of MoVTeNb mixed oxide exhibited 59% of high acrylic acid ... more Highlights The controlled silylation of MoVTeNb mixed oxide exhibited 59% of high acrylic acid yield in oxidation of propane. This is the first success to control consecutive oxidation of acrylic acid at limited activity loss, clarified by both kinetic and model reaction study. The effect of controlled silylation, besides blockage of unfavorable acidic sites, was suggested to be generation of pore mouth openings structure which suppresses consecutive oxidation of acrylic acid size-selectively. ABSTRACT: Acrylic acid is an important industrial chemical, and efficient catalysts for its direct preparation by propane oxidation are highly desirable. For this purpose, neutral silica networks were introduced on the surface of MoVTeNb mixed oxide catalysts by controlled silylation using a methyl silicate oligomer (MS-51). The modified catalysts gave ~56.5% yield of acrylic acid with a selectivity of 77.
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