- Comparing the use of 2-methylenenapthyl, 4-methoxybenzyl, 3,4-dimethoxybenzyl and 2,4,6-trimethoxybenzyl as N-H protecting groups for p-tolyl 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-1-thio-β-d-glucosides
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A hurdle in glycosylation reactions of 2-acetamido glycosyl donors is the formation of a stable and unreactive oxazoline that decreases the yield of these reactions significantly. As an effort to prevent oxazoline formation during glycosylation reactions,
- Sarkar, Sourav,Sucheck, Steven J.
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p. 393 - 400
(2011/04/15)
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- N-ACETYLGLUCOSAMINE DERIVATIVES AND USE THEREOF
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The present invention relates to An N-acetylglucosamine derivative represented by the following formula (1), and a hyaluronic acid production promoting agent containing the same and a skin external preparation containing the same: wherein R1 is a hydrogen atom or an alkyl group having 2 to 18 carbon atoms; R2, R3, and R4 are hydrogen atoms or acyl groups having 2 to 18 carbon atoms and may be all the same or different from others; the steric structure at position 1 may be α or β; provided that R1, R2, R3, and R4 must not be all hydrogen atoms. It is intended to provide an easily available hyaluronic acid production promoting agent and a skin external preparation whereby the production of hyaluronic acid can be promoted in the skin and thus the skin can be maintained in a vital and moist state so that it is expected that the human skin can be prevented from age.
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Page/Page column 14
(2010/02/12)
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- Discovery of the chemical function of glycosidases: Design, synthesis, and evaluation of mass-differentiated carbohydrate libraries
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Equation presented. Discovery of the catalytic chemical function of the many putative glycosidases coded in genomes currently relies on individual testing of possible substrates, usually as their p-nitrophenol conjugate. Herein, we present an alternative chemical proteomics approach using a synthetic mass-differentiated heat-stable substrate library with mass spectrometry readout. Library components do not serve as reaction inhibitors and both primary and secondary enzyme substrates can be delineated.
- Yu, Yang,Ko, Kwang-Seuk,Zea, Corbin J.,Pohl, Nicola L.
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p. 2031 - 2033
(2007/10/03)
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- Catalytic reduction of dimeric acetylated 2-deoxy-2-nitroso-α-D-glucopyranosyl chlorides
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Reduction of tri-O-acetyl-2-deoxy-2-nitroso-α-D-glucopyranosyl chloride dimer with hydrogen and platinum oxide in the presence of methanol or ethanol afforded the corresponding alkyl tri-O-acetyl-2-amino-2-deoxy-β-D-glucopyranoside hydrochloride.In the absence of an alcohol the product was tri-O-acetyl-2-amino-1,5-anhydro-2-deoxy-D-gucitol hydrochloride.The glycosylation/reduction process gave similar results with the galacto isomer.A method is described for the ready and large-scale synthesis of D-galactosamine hydrochloride.
- Nagabhushan, T. L.
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p. 2720 - 2723
(2007/10/02)
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