基于机理的糖苷水解酶抑制剂是模仿天然底物结构的碳水化合物类似物。它们与糖苷水解酶的共价键形成使这些化合物成为化学生物学和潜在候选药物的极佳工具。在这里我们报告了基于环己烯的α-半乳糖吡喃糖苷模拟物的合成以及它们对来自滨海嗜热菌(TmGalA)的α-半乳糖苷酶的抑制活性的动力学和结构特征。通过在基于机理的共价抑制TmGalA的过程中解决几种酶结合物种的结构,我们表明完整抑制剂和产物的Michaelis复合物具有半椅位(2 H 3环己烯片段的构象,而共价连接的中间体则采用扁平的半椅(2 H 3)构象。混合QM / MM计算可确认酶结合物种的结构和电子特性,并深入了解酶活性位点中的关键相互作用。这些见解应能刺激设计具有定制化学性质的基于机理的糖苷水解酶抑制剂。
作者:Emma H. Southgate、Jola Pospech、Junkai Fu、Daniel R. Holycross、David Sarlah
DOI:10.1038/nchem.2594
日期:2016.10
activation of small heteroatom-containing organic molecules—arenophiles—that results in their para-cycloaddition with a variety of aromatic compounds. The approach uses N–N-arenophiles to enable dearomative dihydroxylation and diaminodihydroxylation of simple arenes. This strategy provides direct and selective access to highly functionalized cyclohexenes and cyclohexadienes and is orthogonal to existing
De novo synthesis and lectin binding studies of unsaturated carba-pyranoses
作者:Timo Leermann、Oliver Block、Michael A. L. Podeschwa、Uwe Pfüller、Hans-Josef Altenbach
DOI:10.1039/c003597a
日期:——
Starting from branched para-benzoquinones a practical and highly flexible route is described for the preparation of unsaturated carbapyranoses. The potential of the synthesized galactose analogues to act as competitive inhibitors in lectin-carbohydrate interactions is investigated by means of Surface Plasmon Resonance (SPR) Spectroscopy.
Enantioselective Synthesis of Arene
<i>cis</i>
‐Dihydrodiols from 2‐Pyrones
作者:Xiao‐Wei Liang、Yunlong Zhao、Xu‐Ge Si、Meng‐Meng Xu、Jia‐Hao Tan、Zhi‐Mao Zhang、Cheng‐Gong Zheng、Chao Zheng、Quan Cai
DOI:10.1002/anie.201908284
日期:2019.10.7
An enantioselective chemical synthesis of arene cis-dihydrodiols has been realized from 2-pyrones through sequential ytterbium-catalyzed asymmetric inverse-electron-demand Diels-Alder (IEDDA) reaction of 2-pyrones and retro-Diels-Alder extrusion of CO2 . By using this strategy, a series of substituted arene cis-dihydrodiols can be obtained efficiently with high enantioselectivity (>99 % ee in many
Efficient Synthesis of (+)-MK7607 and its C-1 Epimer via the Stereoselective Transposition of a Tertiary Allylic Alcohol
作者:Chaemin Lim、Dong Jae Baek、Deukjoon Kim、So Won Youn、Sanghee Kim
DOI:10.1021/ol9008987
日期:2009.6.18
These studies provide an efficient and stereoselective synthetic route to (+)-MK7607 and its C-1 epimer from a common intermediate in high overall yields. The synthetic methodologies mainly rely on the stereospecific 1,3-allylic transposition of the hindered tertiary alcohol group through a palladium-catalyzed allylic rearrangement as well as a PBr3-mediated allylic-transposed bromination.
Intrinsic Nucleophilicity of Inverting and Retaining Glycoside Hydrolases Revealed Using Carbasugar Glyco-Tools
作者:Oluwafemi Akintola、Weiwu Ren、Pal John Pal Adabala、Sandeep Bhosale、Yang Wang、Yumeela Ganga-Sah、Robert Britton、Andrew J. Bennet
DOI:10.1021/acscatal.1c01634
日期:2021.8.6
proceeds with little nucleophilic participation by the bound water molecule at the reaction transition state. In contrast, the reaction of carbagalactose substrates with the retaining GH97 enzyme involves a rate-limiting nonchemical step, likely a conformational change, followed by rapid substitution involving a nucleophilic amino acid residue to give a covalently bound intermediate. Considering the structural