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A regio- and stereo-controlled, rhodium(II)-catalyzed amidoglycosylation of alcohols has been developed using O -acetylated glycals, trichloroethoxysulfonamide, and iodosobenzene. This one-pot amidoglycosylation was applied to a variety of primary and secondary alcohols to afford the β- O -glycosides with acceptable yields up to 84%. The reaction would proceed via stereoselective intermolecular aziridination of the glycal from the α-face followed by S N 2 reaction with alcohol at C-1 from the β-face to give 1,2:2,3-di- trans -substituted isomer only. [ABSTRACT FROM AUTHOR]

Abstract: Reactions of O-benzoylated glucopyranosyl halide (I, Br), isolated or generated in situ from per-benzoylated glucose (8a) and trimethylsilyl halide, with various alcohols were efficiently promoted by zinc halide (Cl, Br) or N-bromosuccinimide with a catalytic ZnI2 to give the corresponding 1,2-trans-β-glucosides in good to high yields. When the anomeric halogenation of 8a was carried out in the presence of reactive alcohols, 1,2-cis-α-glucosides were selectively formed. [Copyright &y& Elsevier]

Abstract: Self-assembled monolayer of 11-ferrocenylundecanethiol on gold electrode was used for the potential dependent catalyst for chemiluminescence of luminol. Ferrocene groups adsorbed on gold were oxidized to ferricinium cation species electrochemically, and then catalyzed the chemiluminescene of luminol. The presented system was adopted for detection of glucose in the presence of glucose oxidase since the light emission was detected even in the neutral and weak acid solution. We attempted to use this system for simultaneous detecting of glucose and ascorbic acid by individually measuring the current response and light emission. [Copyright &y& Elsevier]

Abstract: B-type natriuretic peptide (BNP), a peptide hormone, was determined by electrochemical enzyme immunoassay through the following procedure. First, a certain concentration of sample BNP was added to the solution containing anti-BNP antibody modified with acetylcholinesterase (AChE) to undergo the immunological reaction. Then BNP-modified gold particles were added into the BNP/AChE-labeled anti-BNP antibody solution so that the unreacted AChE-labeled anti-BNP antibody was removed from the assay solution. Finally the AChE activity in the solution was measured, based on the chemisorption/electrochemical reductive desorption process of a thiol compound on a silver electrode. The chemisorption (accumulation) of thiocholine, which was produced through the enzymatic reaction, resulted in the enhanced sensitivity for the determination of AChE, and accordingly, for that of BNP. BNP could be determined in the concentration range from 20 to 200ppt (pgmL−1), which indicated that the proposed enzyme immunoassay procedure was high enough for the measurement of the peptide hormone in blood samples. [Copyright &y& Elsevier]

Nearly 30 years after intense investigations of mannide monooleates for use as vaccine adjuvants, a novel adjuvant-active saccharide oleate ester was isolated and identified from the product mixture synthesized from mannitol and oleic acid. The mixture, which contained many kinds of mannide mono- and dioleates and their derivatives, was fractionated by liquid chromatography (LC), and the fraction with the highest adjuvanticity was obtained. Gel permeation chromatography (GPC) showed that it consisted of one major compound with an average molecular weight (MW) 2850. Infrared (IR) absorption and proton nuclear magnetic resonance spectra suggested it had oligosaccharide moieties and oleate domains. These findings suggested that it was an oligosaccharide oleate ester of the average MW 2850. The molecular ratio of oleate chains per monosaccharide unit was approximately 0.8. The ester induced both IgG1 and IgG2a antibody responses in mice in a dispersed form without base oil. This ester thus appears to be one of the adjuvant-active compounds largely contributing to the excellent adjuvanticity of mannide oleate mixture broadly used as vaccine emulsifier. These results and previous findings suggest that the fundamental adjuvanticity of this ‘oligo’ saccharide acylate ester was in accord with the hydrophil-lipophil balance (HLB) theory, similarly to other saccharide acylate esters. It is now expected that this compound will be useful as novel vaccine adjuvant which may induce both Th1 and Th2 type immune responses with low or no toxicity, not only as an vaccine emulsifier but in an aqueous suspension form. [Copyright &y& Elsevier]

Abstract: Mercaptododecyl glycosides containing a terminal β-galactosyl group were prepared from d-galactose or from d-lactose via hexa-O-acetyl-lactal (10) as a key intermediate. Interactions of these glycolipids (5 kinds) and galectins (β-galactoside binding lectins, 6 species) were evaluated by surface plasmon resonance (SPR) method. High binding responses were observed for the lactoside, 2-deoxy-lactoside, and lactosaminide with some galectins (Gal-3, -4, -8), whereas the galactoside and 2,3-dideoxy-lactoside showed low binding activities. [Copyright &y& Elsevier]

Abstract: A series of phosphorylcholine–oligoethylene glycol–alkane thiols were synthesized, and their suppressive effect on the non-specific adsorption of proteins was evaluated by comparison with corresponding oligoethylene glycol–alkane thiols. It was found that phosphorylcholine–oligoethylene glycol–alkane thiols had a greater suppressive effect on the non-specific adsorption of proteins. [Copyright &y& Elsevier]

Abstract: Lewis acid-promoted reactions of peracetylated sugars (glucose, galactose, maltose, lactose) with ω-bromo-1-alkanols (C8, C12) were investigated. ZnCl2 was found to promote the 1,2-trans-glycosylation of the alcohols in toluene at about 60°C in a stereocontrolled manner with better yields than commonly employed promoters such as SnCl4. The ω-bromoalkyl acetylated glycosides were readily converted to ω-mercaptoalkyl glycosides, which are useful for the preparation of glycoclusters. [Copyright &y& Elsevier]

Abstract: An enzyme electrode response to the substrate (S) reduced by the addition of a species (S′) that form a complex with S: an S–S′ complex formed was enzymatically inactive and the complexation, of course, brought about the decrease in the free S-concentration. This could be applied to the measurements of S in a high concentration range. For example, the addition of a phenylboronic acid, which was known to form a complex with diols, to a conventional glucose oxidase (GOx)-based electrode system enabled to determine glucose up to 50mM. Furthermore, the concentration of S′ was determined from the current decrease of the enzyme electrode: the concentration of DNA could be measured by using a peroxidase (HRP)-modified electrode and leuco-methylene blue (MBred), which intercalated into DNA. In a solution containing methylene blue (MB) and hydrogen peroxide, a catalytic current was obtained on the HRP-modified electrode owing to the MB/MBred-recycling sequences. From the decrease of the catalytic current, the concentration of DNA (from salmon testes) was determined with the detection limit of 5ngml−1. [Copyright &y& Elsevier]

A soluble class I cytochrome c of an alkaliphile was purified and characterized, and its primary structure was determined. This is the first example of a soluble class I cytochrome c in alkaliphiles. Cells the alkaliphilic gram-negative bacterium Pseudomonas alcaliphila AL15-21T grown at pH 10 had a soluble cytochrome c content that was more than twofold that of strain AL15-21T cells grown at pH 7 under air-limited conditions. Cytochrome c-552, a soluble cytochrome c with a low molecular weight, was purified from strain AL15-21T cells grown at pH 10 under air-limited conditions. Cytochrome c-552 had a molecular mass of 7.5 kDa and exhibited an almost fully reduced state in the resting form, which exhibited absorption maxima at wavelengths of 552, 523 and 417 nm. In the oxidized state, it exhibited an absorption maximum at 412 nm when it was oxidized by ferricyanide, its isoelectric point (pI) was 4.3 and it contained one heme c as a prosthetic group. Cytochrome c-552 was autoreduced at pH 10, and the autoreduction was reproducible. On the other hand, the autoreduction of cytochrome c-552 was not observed at pH 7.0. When pH was increased from 7.0 to 8.3, its midpoint redox potentials (E m values) increased from +228 mV to +276 mV as determined by redox titrations, and from +217 mV to +275 mV as determined by cyclic voltammetric measurements. The amino acid sequence deduced by cytochrome c-552 gene analysis revealed that the sequence consists of 96 residues, including 19 residues as an amino-terminal signal peptide. A phylogenetic tree based on amino acid sequence indicated that the protein belongs to group 4, cytochrome c 5 in class I cytochrome c. [Copyright &y& Elsevier]