2,3,5,6-tetra-O-acetyl-β-D-galactofuranosyl trichloroacetimidate | 396716-71-5

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: 2,3,5,6-tetra-O-acetyl-β-D-galactofuranosyl trichloroacetimidate
• 英文别名: Galf2Ac3Ac5Ac6Ac(b)-O-C(NH)CCl3；[(2R)-2-acetyloxy-2-[(2S,3S,4R,5S)-3,4-diacetyloxy-5-(2,2,2-trichloroethanimidoyl)oxyoxolan-2-yl]ethyl] acetate
• CAS: 396716-71-5
• 化学式: C₁₆H₂₀Cl₃NO₁₀
• 分子量: 492.695
• InChiKey: OYTWFVAPTNPTCO-HTOAHKCRSA-N

物化性质

• 沸点：
  487.9±55.0 °C(Predicted)
• 密度：
  1.55±0.1 g/cm3(Temp: 20 °C; Press: 760 Torr)(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  1.7
• 重原子数：
  30
• 可旋转键数：
  12
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.69
• 拓扑面积：
  148
• 氢给体数：
  1
• 氢受体数：
  11

反应信息

• 作为反应物：
  描述：

  N-乙酰基-L-半胱氨酸甲酯 、 2,3,5,6-tetra-O-acetyl-β-D-galactofuranosyl trichloroacetimidate 在 三氟甲磺酸三甲基硅酯 作用下， 以 二氯甲烷 为溶剂， 反应 1.0h， 以79%的产率得到N-acetyl-S-(2,3,5,6-tetra-O-acetyl-1-thio-β-D-galactofuranosyl)-L-cysteinyl methyl ester
  参考文献：
  名称：

  Direct access to new β-d-galactofuranoconjugates: application to the synthesis of galactofuranosyl-l-cysteine and l-serine

  摘要：

  Galactofuranose post-translational modifications, although quite rare, were detected in some biomolecules produced by parasites. While hexopyranosides were already linked to various peptides and proteins, few hexofuranosides have been artificially conjugated to amino acids. We thus report herein a robust glycosylation methodology to obtain S-alkyl, O-serine and S-cysteine-beta-D-galactofuranosides starting from readily available galactofuranose donors. O-Acetyl, thioimidoyl and acetimidoyl donors were compared in terms of yields and selectivity when reacted with mercaptans, L-cysteine and L-serine. Acetimidates turned out to be the best notably for amino acids glycosylation. (C) 2011 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tetlet.2011.01.001
• 作为产物：
  描述：

  2,3,5,6-tetra-O-acetyl-D-galactofuranose 、 三氯乙腈 在 1,8-二氮杂双环[5.4.0]十一碳-7-烯 作用下， 以 二氯甲烷 为溶剂， 反应 1.0h， 以88%的产率得到2,3,5,6-tetra-O-acetyl-β-D-galactofuranosyl trichloroacetimidate
  参考文献：
  名称：

  Direct access to new β-d-galactofuranoconjugates: application to the synthesis of galactofuranosyl-l-cysteine and l-serine

  摘要：

  Galactofuranose post-translational modifications, although quite rare, were detected in some biomolecules produced by parasites. While hexopyranosides were already linked to various peptides and proteins, few hexofuranosides have been artificially conjugated to amino acids. We thus report herein a robust glycosylation methodology to obtain S-alkyl, O-serine and S-cysteine-beta-D-galactofuranosides starting from readily available galactofuranose donors. O-Acetyl, thioimidoyl and acetimidoyl donors were compared in terms of yields and selectivity when reacted with mercaptans, L-cysteine and L-serine. Acetimidates turned out to be the best notably for amino acids glycosylation. (C) 2011 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tetlet.2011.01.001

文献信息

• Synthesis of galactofuranose-based acceptor substrates for the study of the carbohydrate polymerase GlfT2
  作者：Rebecca A. Splain、Laura L. Kiessling

  DOI：10.1016/j.bmc.2010.04.068

  日期：2010.6.1

  Despite the prevalence and importance of carbohydrate polymers, the molecular details of their biosynthesis remain elusive. Many enzymes responsible for the synthesis of carbohydrate polymers require a 'primer' or 'initiator' carbohydrate sequence. One example of such an enzyme is the mycobacterial galactofuranosyltransferase GlfT2 (Rv3808c), which generates an essential cell wall building block. We recently demonstrated that recombinant GlfT2 is capable of producing a polymer composed of alternating beta-(1,5) and beta-(1,6)-linked galactofuranose (Galf) residues. Intriguingly, the length of the polymers produced from a synthetic glycosyl acceptor is consistent with those found in the cell wall. To probe the mechanism by which polymer length is controlled, a collection of initiator substrates has been assembled. The central feature of the synthetic route is a ruthenium-catalyzed cross-metathesis as the penultimate transformation. Access to synthetic substrates has led us to postulate a new mechanism for length control in this template-independent polymerization. Moreover, our investigations indicate that lipids possessing but a single galactofuranose residue can act as substrates for GlfT2. (C) 2010 Elsevier Ltd. All rights reserved.