[GRAPHICS]The design, synthesis, and preliminary evaluation of the first example of synthetic pentasaccharide (1) that shows marked rate enhancement and specificity for the hydrolysis of GTP to GDP and orthophosphate (OP) are reported. At the concentration ratios of GTP/1 = 3.6 and GTP/Mg2+ = 1 (pH 7.1, 50 degreesC), a rate enhancement of about 500-fold was obtained.
An efficient and recyclable catalyst for the cleavage of tert-butyldiphenylsilyl ethers
摘要:
An efficient, chemoselective, and environment-friendly method for the deprotection of tert-butyldiphenylsilyl ethers mediated by triflic acid supported on silica gel is reported. A wide range of tert-butyldiphenylsilyl ethers derived from carbohydrate and saponin residues can be smoothly cleaved in the presence of various types of other protecting groups in good to excellent yields in acetonitrile. This heterogeneous reaction does not require aqueous workup, and the supported catalyst can be readily recycled. (C) 2012 Elsevier Ltd. All rights reserved.
8-(Methyltosylaminoethynyl)-1-naphthyl (MTAEN) Glycosides: Potent Donors in Glycosides Synthesis
作者:Si-Yu Zhou、Xin-Ping Hu、Hui-Juan Liu、Qing-Ju Zhang、Jin-Xi Liao、Yuan-Hong Tu、Jian-Song Sun
DOI:10.1021/acs.orglett.1c04102
日期:2022.1.21
efficient glycosylation protocol has been established. The MTAEN glycosylation protocol exhibits the merits of shelf-stable donors, mild catalytic promotion conditions, considerably extended substrate scope encompassing both free alcohols, silylated alcohols, nucleobases, primary amides, and C-type nucleophile acceptors, and applicability to various one-pot strategies for highly efficient synthesis of oligosaccharides
Synthesis of 1,6-anhydro sugars catalyzed by silica supported perchloric acid
作者:Yuexing Chun、Shiqiang Yan、Xiangpeng Li、Ning Ding、Wei Zhang、Peng Wang、Ming Li、Yingxia Li
DOI:10.1016/j.tetlet.2011.09.055
日期:2011.11
A new and efficient method for the preparation of 1,6-anhydro sugars using silica supported perchloricacid as a catalyst is described. The catalyst is heterogeneous and 1,6-anhydro sugars could be formed within a few minutes with good yields.
An efficient method for the cleavage of <i>tert</i>-butyldiphenylsilyl ethers catalyzed by 1,3-dibromo-5,5-dimethylhydantoin
作者:Zong Han
DOI:10.1080/07328303.2022.2031206
日期:2022.1.2
Abstract An efficient method for the deprotection of tert-butyldiphenylsilyl (TBDPS) ethers using 1,3-dibromo-5,5-dimethylhydantoin (DBH) as catalyst and dimethyl sulfoxide (DMSO) as solvent has been established. This method is useful for many kinds of compounds, such as carbohydrates, steroids, benzyl alcohols and primary fatty alcohols. Substrates bearing acetates, benzoates, pivaloates, mesylates, and benzyl
2-amino-2-deoxy glucose by selective introduction of different N-protecting (NPhth and NHTroc) and anomeric leaving groups (ethylthio and phenylthio) enabled highly efficient oligosaccharidesynthesis in a one-pot manner. One-pot sequential glycosylation of three and four units of 2-amino-2-deoxy glucose gave trisaccharides and tetrasaccharide in 50-81% yields.