allyl 6-O-acetyl-2,3,5-tri-O-benzoyl-β-D-galactofuranoside | 845532-31-2

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: allyl 6-O-acetyl-2,3,5-tri-O-benzoyl-β-D-galactofuranoside
• CAS: 845532-31-2
• 化学式: C₃₂H₃₀O₁₀
• 分子量: 574.584
• InChiKey: ZWDFOKAHAAJOTL-IUBCVFBCSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.15
• 重原子数：
  42.0
• 可旋转键数：
  12.0
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  123.66
• 氢给体数：
  0.0
• 氢受体数：
  10.0

反应信息

• 作为反应物：
  描述：

  allyl 6-O-acetyl-2,3,5-tri-O-benzoyl-β-D-galactofuranoside 在 甲醇 、 N-碘代丁二酰亚胺 、 silver trifluoromethanesulfonate 、 三乙胺 、 乙酰氯 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 反应 13.0h， 生成 allyl 2,3,5-tri-O-benzoyl-β-D-galactofuranosyl-(1,6)-2,3,6-tri-O-benzoyl-β-D-galactofuranoside
  参考文献：
  名称：

  Fidelity and Promiscuity of a Mycobacterial Glycosyltransferase

  摘要：

  Members of the genus Mycobacterium cause devastating human diseases, including tuberculosis. Mycobacterium tuberculosis can resist some antibiotics because of its durable and impermeable cell envelope. This barrier is assembled from saccharide building blocks not found in mammals, including galactofuranose (Galf). Within the cell envelope, Galf residues are linked together to afford an essential polysaccharide, termed the galactan. The formation of this polymer is catalyzed by the glycosyltransferase GlfT2, a processive carbohydrate polymerase, which generates a sequence-specific polysaccharide with alternating regioisomeric beta(1-5) and beta(1-6) Galf linkages. GlfT2 exhibits high fidelity in linkage formation, as it will terminate polymerization rather than deviate from its linkage pattern. These findings suggest that GlfT2 would prefer an acceptor with a canonical alternating beta(1-5) and beta(1-6) Galf sequence. To test this hypothesis, we devised a synthetic route to assemble oligosaccharides with natural and non-natural sequences. GlfT2 could elongate each of these acceptors, even those with non-natural linkage patterns. These data indicate that the glycosyltransferase is surprisingly promiscuous in its substrate preferences. However, GlfT2 did favor some substrates: it preferentially acted on those in which the lipid-bearing Galf residue was connected to the sequence by a beta(1-6) glycosidic linkage. The finding that the relative positioning of the lipid and the non-reducing end of the acceptor influences substrate selectivity is consistent with a role for the lipid in acceptor binding. The data also suggest that the fidelity of GlfT2 for generating an alternating beta(1-5) and beta(1-6) pattern of Galf residues arises not from preferential substrate binding but during processive elongation. These observations suggest that inhibiting the action of GlfT2 will afford changes in cell wall structure.

  DOI：

  10.1021/jacs.6b04481
• 作为产物：
  描述：

  烯丙醇 、 6-O-acetyl-2,3,5-tri-O-benzoyl-α,β-D-galactofuranosyl acetate 在 三氟化硼乙醚 作用下， 以 二氯甲烷 为溶剂， 以80%的产率得到allyl 6-O-acetyl-2,3,5-tri-O-benzoyl-β-D-galactofuranoside
  参考文献：
  名称：

  Synthesis of galactofuranose-based acceptor substrates for the study of the carbohydrate polymerase GlfT2

  摘要：

  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.

  DOI：

  10.1016/j.bmc.2010.04.068

文献信息

• An efficient and concise synthesis of a β-(1→6)-linked d-galactofuranosyl hexasaccharide
  作者：Guohua Zhang、Mingkun Fu、Jun Ning

  DOI：10.1016/j.carres.2004.11.001

  日期：2005.1

  A beta-(1-->6)-linked D-galactofuranosyl hexasaccharide was synthesized efficiently in a block construction manner by the well-known Schmidt glycosylation method using 6-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-galactofuranosyl trichloroacetimidate (1) and allyl 2,3,5-tri-O-benzoyl-beta-D-galactofuranoside (3) as the key synthons. Coupling of 3 with 1 gave beta-(1-->6)-linked disaccharide 4. Subsequent

  通过使用6-O-乙酰基-2,3,5-三-O-苯甲酰基的众所周知的施密特糖基化方法，以嵌段结构的方式有效地合成β-（1→6）-连接的D-半呋喃呋喃糖基六糖。 -β-D-半呋喃糖基三氯乙酰亚氨酸盐（1）和烯丙基2,3,5-三-O-苯甲酰基-β-D-半乳糖醛酸呋喃糖苷（3）为关键合成子。3与1的偶联得到β-（1-> 6）-连接的二糖4。随后4的选择性脱乙酰化得到二糖受体5，而4的去甲酰化反应随后形成三氯乙酰亚氨酸生成了二糖供体6。5与6的缩合。得到四糖7，随后脱乙酰基得到四糖受体8。最后，将8与6偶联，然后进行脱酰基，得到目标β-（1→6）连接的半乳​​糖呋喃糖六糖10。