The Experts below are selected from a list of 114 Experts worldwide ranked by ideXlab platform
Shigekazu Yamazaki - One of the best experts on this subject based on the ideXlab platform.
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Chromium(VI) oxide-mediated oxidation of polyalkyl-polypyridines to polypyridine-polycarboxylic Acids with Periodic Acid
Synthetic Communications, 2019Co-Authors: Shigekazu YamazakiAbstract:Abstract4,4′-Dicarboxy-2,2′-bipyridine was synthesized quantitatively by chromium(VI) oxide-mediated oxidation of 4,4′-dimethyl-2,2′-bipyridine or 4,4′-diethyl-2,2′-bipyridine with Periodic Acid as...
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Chromium(VI) oxide-mediated oxidation of polyalkyl-polypyridines to polypyridine-polycarboxylic Acids with Periodic Acid
Synthetic Communications, 2019Co-Authors: Shigekazu YamazakiAbstract:4,4′-Dicarboxy-2,2′-bipyridine was synthesized quantitatively by chromium(VI) oxide-mediated oxidation of 4,4′-dimethyl-2,2′-bipyridine or 4,4′-diethyl-2,2′-bipyridine with Periodic Acid as the ter...
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Chromium(VI) oxide-catalyzed oxidation of arenes with Periodic Acid
Tetrahedron Letters, 2001Co-Authors: Shigekazu YamazakiAbstract:Chromium(VI) oxide was found to catalyze the oxidation of arenes such as naphthalenes and anthrathene to the corresponding quinones with Periodic Acid as the terminal oxidant in acetonitrile. 2-Methylnaphthalene was oxidized smoothly to 2-methyl-1,4-naphthoquinone (vitamin K3) by the catalytic system in high yield and regioselectivity.
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Chromium(VI) Oxide-Catalyzed Benzylic Oxidation with Periodic Acid
Organic Letters, 1999Co-Authors: Shigekazu YamazakiAbstract:CrO3 has been found to be an efficient catalyst for benzylic oxidation with Periodic Acid as the terminal oxidant in acetonitrile. Substituted toluenes with an electron-withdrawing group at the 4- or 3-position and diarylmethanes such as diphenylmethane and fluorene were oxidized to the corresponding substituted benzoic Acids and ketones in excellent yields. Benzyl ethers such as isochroman and phthalan were converted to 3,4-dihydroisocoumarin and phthalide in quantitative yields.
Mark L. Trudell - One of the best experts on this subject based on the ideXlab platform.
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Novel chromium(VI) catalyzed oxidation of N-alkylamides to imides with Periodic Acid
Chemical communications (Cambridge England), 2004Co-Authors: Suhong Zhang, Mark L. TrudellAbstract:A novel and practical procedure for preparation of imides is described using chromium(VI) oxide to catalyze the oxidation of N-alkylamides with Periodic Acid in the presence of acetic anhydride in acetonitrile.
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Chromium(VI) oxide catalyzed oxidation of sulfides to sulfones with Periodic Acid
The Journal of organic chemistry, 2003Co-Authors: Jie Cheng, Mark L. TrudellAbstract:A highly efficient and selective oxidation of sulfides to sulfones with Periodic Acid catalyzed by CrO3 is described. A variety of electron-rich and electron-deficient sulfides were oxidized to sulfones with 2 mol % CrO3 in acetonitrile at room temperature in excellent yields. Sulfides with other readily oxidized functional groups were selectively oxidized to sulfones in high yields with 10 mol % CrO3 in ethyl acetate/acetonitrile at −35 °C.
Jean-michel Vatèle - One of the best experts on this subject based on the ideXlab platform.
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tempo nbu4br catalyzed selective alcohol oxidation with Periodic Acid
Synlett, 2014Co-Authors: Mariam Attoui, Jean-michel VatèleAbstract:Oxidation of primary and secondary alcohols, using catalytic amounts of TEMPO and tetra-n-butylammonium bromide in combination with Periodic Acid and wet alumina in dichloromethane is described. This oxidizing system is compatible with a broad range of functional groups and Acid-sensitive protecting groups. Chemoselective oxidation of secondary alcohols in the presence of primary alcohols was observed.
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TEMPO/NBU4Br-catalyzed selective alcohol oxidation with Periodic Acid.
SYNLETT, 2014Co-Authors: Mariam Atoui, Jean-michel VatèleAbstract:Oxidation of primary and secondary alcohols, using catalytic amounts of TEMPO and tetra-n-butylammonium bromide in combination with Periodic Acid and wet alumina in dichloromethane is described. This oxidizing system is compatible with a broad range of functional groups and Acid-sensitive protecting groups. Chemoselective oxidation of secondary alcohols in the presence of primary alcohols was observed.
Lokesh Joshi - One of the best experts on this subject based on the ideXlab platform.
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Periodic Acid schiff s reagent assay for carbohydrates in a microtiter plate format
Analytical Biochemistry, 2011Co-Authors: Michelle Kilcoyne, Jared Q. Gerlach, Mark Farrell, Veer P. Bhavanandan, Lokesh JoshiAbstract:Microtiter plate colorimetric assays are widely used for analysis of carbohydrates and glycoconjugates. However, mucins are often not easily detected, as they have low neutral sugar content. We have adapted and optimised the Periodic Acid-Schiff's reagent (PAS) staining for microtiter plate assay by examining five factors: concentration and volume of Periodic Acid, oxidation time, volume of Schiff's reagent, and color development time. This assay requires just 25 μl of sample, utilises standardised Schiff's reagent, and has decreased assay time (140 min to completion). Seventeen monosaccharides (Acidic, neutral, basic, phosphorylated, and deoxy) and four disaccharides were assessed. PAS-positive carbohydrates (amino, N-acetylamino, deoxy, and certain neutral monosaccharides, and sialic Acids) responded linearly within a 10-100 nmol range approximately, which varied for each carbohydrate. The assay response for fetuin and porcine gastric mucin (PGM) was linear up to 150 μg (highest concentration tested), with no response from nonglycosylated protein. A lower response for asialofetuin was observed, but desialylated PGM preparations were similar or higher in response than their sialylated counterparts. The simplicity and low sample consumption of this method make it an excellent choice for screening or quantitation of chromatographic fractions containing carbohydrates and glycoconjugates, especially in the case of mucins.
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Periodic Acid–Schiff’s reagent assay for carbohydrates in a microtiter plate format
Analytical biochemistry, 2011Co-Authors: Michelle Kilcoyne, Jared Q. Gerlach, Mark Farrell, Veer P. Bhavanandan, Lokesh JoshiAbstract:Microtiter plate colorimetric assays are widely used for analysis of carbohydrates and glycoconjugates. However, mucins are often not easily detected, as they have low neutral sugar content. We have adapted and optimised the Periodic Acid-Schiff's reagent (PAS) staining for microtiter plate assay by examining five factors: concentration and volume of Periodic Acid, oxidation time, volume of Schiff's reagent, and color development time. This assay requires just 25 μl of sample, utilises standardised Schiff's reagent, and has decreased assay time (140 min to completion). Seventeen monosaccharides (Acidic, neutral, basic, phosphorylated, and deoxy) and four disaccharides were assessed. PAS-positive carbohydrates (amino, N-acetylamino, deoxy, and certain neutral monosaccharides, and sialic Acids) responded linearly within a 10-100 nmol range approximately, which varied for each carbohydrate. The assay response for fetuin and porcine gastric mucin (PGM) was linear up to 150 μg (highest concentration tested), with no response from nonglycosylated protein. A lower response for asialofetuin was observed, but desialylated PGM preparations were similar or higher in response than their sialylated counterparts. The simplicity and low sample consumption of this method make it an excellent choice for screening or quantitation of chromatographic fractions containing carbohydrates and glycoconjugates, especially in the case of mucins.
Theodore I. Malinin - One of the best experts on this subject based on the ideXlab platform.
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Calcium is required for the mitogenic activation of lymphocytes by Periodic Acid oxidation.
Biochemical and biophysical research communications, 1992Co-Authors: Francis J. Hornicek, George I. Malinin, Theodore I. MalininAbstract:Abstract This investigation of Ca 2+ requirements for the mitogenic activation of lymphocytes by Periodic Acid has shown that oxidation by periodate causes an immediate and transient increase of Ca 2+ influx and efflux in oxidized cells. Oxidized lymphocytes maintained in the medium containing 0.2 mM Ca 2+ failed to proliferate or to produce IL-2, whereas a 1.4 mM Ca 2+ concentration was shown to be sufficient to sustain cellular proliferation and IL-2 secretion. These results indicate that mitogenic activation of lymphocytes by Periodic Acid oxidation is Ca 2+ -dependent.
