methyl 3,4-di-O-acetyl-β-D-xylopyranoside | 77217-82-4

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl 3,4-di-O-acetyl-β-D-xylopyranoside
• 英文别名: 3,4-di-O-Ac-MeXylp；Methyl 3,4-di-O-acetyl-b-D-xylopyranoside；[(3R,4R,5R,6R)-4-acetyloxy-5-hydroxy-6-methoxyoxan-3-yl] acetate
• CAS: 77217-82-4；63629-70-9
• 化学式: C₁₀H₁₆O₇
• 分子量: 248.233
• InChiKey: UFNCBPFUCKYNDR-DOLQZWNJSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -0.8
• 重原子数：
  17
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.8
• 拓扑面积：
  91.3
• 氢给体数：
  1
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  methyl 3,4-di-O-acetyl-β-D-xylopyranoside 在 2,6-二叔丁基-4-甲基吡啶 、 4 A molecular sieve 、 氨 、 silver trifluoromethanesulfonate 作用下， 以 乙醚 、 二氯甲烷 为溶剂， 反应 159.0h， 生成 Methyl 3,4-di-O-acetyl-2-O-<3,4,6-tri-O-acetyl-2-O-(2,3,4-tri-O-benzyl-α-L-fucopyranosyl)-β-D-galactopyranosyl>-β-D-xylopyranoside
  参考文献：
  名称：

  Regioselective Acetylations of Alkyl .beta.-D-Xylopyranosides by Use of Lipase PS in Organic Solvents and Application to the Chemoenzymic Synthesis of Oligosaccharides

  摘要：

  Aglycon structure and solvent can change the regioselectivity of the acetylation of alkyl beta-D-xylopyranosides, catalyzed by lipase PS. The acetylation of methyl beta-D-xylopyranoside (3) in acetonitrile gave the 3,4-diacetate 4 exclusively, whereas the reaction of octyl beta-D-xylopyranoside (5) gave a mixture of 2,4- and 3,4-diacetates (6 and 7) in 1.0:1.3 and 3.6:1.0 ratios, in acetonitrile and hexane, respectively. The effect of several solvents on the selectivity in the monoacetylation of 5 was studied. The 2-monoacetate 8 was preferentially formed over the 3- and 4-monoacetates (9 and 10) in hydrophobic solvents. High yields of partially acetylated xylose derivatives were obtained, which were used in the syntheses of a disaccharide showing liquid crystal properties, an intermediate for the synthesis of proteoglycan fragments, and a trisaccharide potential inhibitor of plant growth.

  DOI：

  10.1021/jo00102a029
• 作为产物：
  描述：

  乙酸乙烯酯 、 甲基-β-D-吡喃木糖苷 在 Lipase PS 作用下， 以 叔丁醇 为溶剂， 反应 48.0h， 以87%的产率得到methyl 3,4-di-O-acetyl-β-D-xylopyranoside
  参考文献：
  名称：

  从甲基β-d-吡喃吡喃糖苷到甲基4-O-苄基-2,3-脱水-β-d-吡喃吡喃糖苷的有效化学酶促路线

  摘要：

  摘要以五步法制得了甲基4-O-苄基-2,3-脱水-β-d-吡喃吡喃糖苷的中间体，该中间体是制备经C-2修饰的甲基β-d-吡喃吡喃糖苷衍生物的中间体，收率58％。合成序列从甲基β-d-吡喃吡喃糖苷开始，经过两个主要步骤，包括脂酶PS催化的区域选择性酶促乙酰化和脱乙酰化。

  DOI：

  10.1016/j.carres.2003.10.005

文献信息

• Positional specificity of Flavobacterium johnsoniae acetylxylan esterase and acetyl group migration on xylan main chain
  作者：Vladimír Puchart、Morten Gjermansen、Mária Mastihubová、Kristian B.R. Mørkeberg Krogh、Peter Biely

  DOI：10.1016/j.carbpol.2019.115783

  日期：2020.3

  are attacked with a significantly reduced affinity. The resulting 2-O-acetylated xylan was used to investigate for the first time the migration of the 2-O-acetyl group to position 3 within the polysaccharide. In contrast to easy acetyl group migration along the monomeric xylopyranosides or non-reducing-end terminal Xylp residues of xylooligosaccharides, such a migration in the polymer required much longer

  一种新的约翰逊弗氏菌分离物编码的酶与最近发现的新型乙酰木聚糖酯酶基本相同，该酶能够从4-O-甲基-d-葡萄糖醛酸取代的吡喃吡喃糖基（Xylp）残基中释放3-O-乙酰基（Razeq等等人，2018年）。除了乙酰葡糖醛酸木聚糖中2-O-MeGlcA取代的Xylp残基的去酯化作用外，该酶还对双乙酰化的Xylp残基同样起作用，从中仅释放3-O-乙酰基，而2-O-乙酰基则保持不变。3-O-单乙酰基化的木糖残基以显着降低的亲和力被攻击。所得的2-O-乙酰化木聚糖首次用于研究2-O-乙酰基向多糖内第3位的迁移。与容易的乙酰基沿着木糖寡糖的单体木糖吡喃糖苷或非还原末端Xylp残基迁移相比，这种在聚合物中的迁移需要在100°C下加热更长的时间。然而，木聚糖3-O-脱乙酰基酶的特异性对乙酰化的甲基和4-硝基苯基木吡喃葡萄糖苷没有那么严格的要求。
• A New Family of Carbohydrate Esterases Is Represented by a GDSL Hydrolase/Acetylxylan Esterase from Geobacillus stearothermophilus
  作者：Onit Alalouf、Yael Balazs、Margarita Volkinshtein、Yael Grimpel、Gil Shoham、Yuval Shoham

  DOI：10.1074/jbc.m111.301051

  日期：2011.12

  hydrolyzes the synthetic substrates 2-naphthyl acetate, 4-nitrophenyl acetate, 4-methylumbelliferyl acetate, and phenyl acetate. The pH profiles for k(cat) and k(cat)/K(m) suggest the existence of two ionizable groups affecting the binding of the substrate to the enzyme. Using NMR spectroscopy, the regioselectivity of Axe2 was directly determined with the aid of one-dimensional selective total correlation

  乙酰木聚糖酯酶水解木聚糖中木糖部分 2 和/或 3 位乙酰基的酯键，并在增强木聚糖酶对木聚糖骨架的可及性方面发挥重要作用。嗜热细菌 Geobacillus stearothermophilus T-6 的半纤维素分解系统包含推定的乙酰木聚糖酯酶基因 axe2。该基因产物属于 GDSL 水解酶家族，与 CAZy 数据库中的任何碳水化合物酯酶不具有序列同源性。axe2 基因由木糖诱导，纯化的基因产物使过乙酸木二糖（完全乙酰化）完全脱乙酰化，并水解合成底物乙酸 2-萘酯、4-硝基苯乙酸酯、4-甲基伞形酮乙酸酯和乙酸苯酯。k(cat) 和k(cat)/K(m) 的pH 配置文件表明存在影响底物与酶的结合的两个可电离基团。使用 NMR 光谱，借助一维选择性全相关光谱直接测定 Axe2 的区域选择性。甲基 2,3,4-三-O-乙酰基-β-d-吡喃木糖苷在 2 位或 3 位和 4 位快速脱乙酰，分别得到双乙酰或单乙酰中间体；甲基
• Trichoderma reesei CE16 acetyl esterase and its role in enzymatic degradation of acetylated hemicellulose
  作者：Peter Biely、Mária Cziszárová、Jane W. Agger、Xin-Liang Li、Vladimír Puchart、Mária Vršanská、Vincent G.H. Eijsink、Bjorge Westereng

  DOI：10.1016/j.bbagen.2013.10.008

  日期：2014.1

  non-reducing end sugar may involve migration of acetyl groups to position 4, which also serves as substrate of the TrCE16 esterase. CONCLUSION Concerted action of CtGH10 xylanase, an AcXE and TrCE16 AcE resulted in close to complete deacetylation of neutral xylooligosaccharides, whereas substitution with MeGlcA prevents removal of acetyl groups from only a small fraction of the aldouronic acids. Experiments

  背景技术里氏木霉CE16乙酰酯酶（AcE）是真菌的植物细胞壁降解系统的组分。该酶的作用就像是一种外向性脱乙酰基酶，可从非还原性末端糖残基上除去乙酰基。方法在这项工作中，我们证明了使用MALDI ToF MS对天然乙酰化低聚木糖的这种外脱乙酰活性。结果GH10木聚糖酶和乙酰木聚糖酯酶（AcXEs）的共同作用导致形成中性和酸性的木寡糖，主要在其非还原端带有一些抗性乙酰基。我们在这里显示这些乙酰基充当Tr​​CE16 AcE的目标。最突出的靶标是线性中性木糖寡糖的非还原性末端Xylp残基上或非还原性末端带有MeGlcA的醛糖醛酸上的3-O-乙酰基。非还原性末端糖的脱乙酰化可能涉及乙酰基向位置4的迁移，该位置4也用作TrCE16酯酶的底物。结论CtGH10木聚糖酶，AcXE和TrCE16 AcE的协同作用导致中性低聚木糖几乎完全脱乙酰，而用MeGlcA取代可防止仅从一小部分醛糖醛酸中除去乙酰基。用
• Positional specifity of acetylxylan esterases on natural polysaccharide: An NMR study
  作者：Iveta Uhliariková、Mária Vršanská、Barry V. McCleary、Peter Biely

  DOI：10.1016/j.bbagen.2013.01.011

  日期：2013.6

  Background: Microbial degradation of acetylated plant hemicelluloses involves besides enzymes cleaving the glycosidic linkages also deacetylating enzymes. A detailed knowledge of the mode of action of these enzymes is important in view of the development of efficient bioconversion of plant materials that did not undergo alkaline pretreatment leading to hydrolysis of ester linkages.Methods: In this work deacetylation of hardwood acetylglucuronoxylan by acetybcylan esterases from Streptomyces lividans (carbohydrate esterase family 4) and Oipinomyces sp. (carbohydrate esterase family 6) was monitored by H-1-NMR spectroscopy.Results: The H-1-NMR resonances of all acetyl groups in the polysaccharide were fully assigned. The targets of both enzymes are 2- and 3-monoacetylated xylopyranosyl residues and, in the case of the Orpinomyces sp. enzyme, also the 2,3-di-O-acetylated xylopyranosyl residues. Both enzymes do not recognize as a substrate the 3-O-acetyl group on xylopyranosyl residues alpha-1,2-substituted with 4-O-methyl-D-glucuronic acid.Conclusions: The H-1-NMR spectroscopy approach to study positional and substrate specificity of AcXEs outlined in this work appears to be a simple way to characterize catalytic properties of enzymes belonging to various CE families. Significance: The results contribute to development of efficient and environmentally friendly procedures for enzymatic degradation of plant biomass. (c) 2013 Elsevier B.V. All rights reserved.
• Schraml, Jan; Petrakova, Eva; Pihar, Otomar, Collection of Czechoslovak Chemical Communications, 1983, vol. 48, # 7, p. 1829 - 1841
  作者：Schraml, Jan、Petrakova, Eva、Pihar, Otomar、Hirsch, Jan、Chvalovsky, Vaclav

  DOI：——

  日期：——