Dibromopentanyl 2,4-di-O-benzyl-6-O-(chloroacetyl)-α-D-mannopyranoside | 143706-44-9

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 脂肪酰基
• 英文名称: Dibromopentanyl 2,4-di-O-benzyl-6-O-(chloroacetyl)-α-D-mannopyranoside
• 英文别名: [(2R,3S,4S,5S,6S)-6-(4,5-dibromopentoxy)-4-hydroxy-3,5-bis(phenylmethoxy)oxan-2-yl]methyl 2-chloroacetate
• CAS: 143706-44-9
• 化学式: C₂₇H₃₃Br₂ClO₇
• 分子量: 664.816
• InChiKey: DXBJVOTVKGIAJU-ORUYPKMRSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5
• 重原子数：
  37
• 可旋转键数：
  16
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.52
• 拓扑面积：
  83.4
• 氢给体数：
  1
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  Dibromopentanyl 2,4-di-O-benzyl-6-O-(chloroacetyl)-α-D-mannopyranoside 在 samarium diiodide 作用下， 以 四氢呋喃 为溶剂， 以58%的产率得到Acetic acid (2R,3S,4S,5S,6S)-3,5-bis-benzyloxy-6-(4,5-dibromo-pentyloxy)-4-hydroxy-tetrahydro-pyran-2-ylmethyl ester
  参考文献：
  名称：

  Methods for Debrominating 4,5-Dibromopentanyl Glycosides

  摘要：

  Debromination of 4,5-dibromopentanyl glycosides to (re)generate n-pentenyl glycosides has been accomplished using zinc, samarium(II) iodide, and sodium iodide, respectively. The choice of reagent is dependent upon the reactivity of the substrate, as well as the protecting groups thereon.

  DOI：

  10.1080/07328309608005425
• 作为产物：
  描述：

  1,3,6-tri-O-acetyl-2,4-di-O-benzyl-α-D-mannopyranose 在 吡啶 、 四乙基溴化铵 、 溴 、 sodium methylate 、 四氯化锡 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 反应 2.0h， 生成 Dibromopentanyl 2,4-di-O-benzyl-6-O-(chloroacetyl)-α-D-mannopyranoside
  参考文献：
  名称：

  n-Pentenyl Mannoside Precursors for Synthesis of the Nonamannan Component of High Mannose Glycoproteins

  摘要：

  The high-mannose oligosaccharide 1 is present on the conserved V3 loop of the viral coat of HIV1 known as GP-120. The mannan portion of this molecule has been prepared by utilization of halogen-promoted n-pentenyl glycoside (NPG) coupling. Two advantageous properties of NPG's facilitated construction of 1, one being the ability to activate the donor, even when C2 esterified (i.e., ''disarmed''), with NIS/Et(3)SiOTf, under which all reactions are complete within the time required to take a TLC sample. The second advantage was the ''side-tracking'' strategy which allowed the pentenyl group of a glycosyl acceptor to be rendered temporarily inactive by conversion to the dibromide. After coupling, the ''side-tracked'' NPG could be reactivated by reductive elimination to serve as the glycosyl donor in a subsequent step. With the appropriately protected monosaccharide precursors in hand, the nonamannan could be assembled by a virtually iterative protocol involving deprotection-coupling- deprotection-coupling...etc. as the only synthetic manipulations.

  DOI：

  10.1021/jo00095a020

文献信息

• n-Pentenyl glycoside methodology for rapid assembly of homoglycans exemplified with the nonasaccharide component of a high-mannose glycoprotein
  作者：J. Robert Merritt、Bert Fraser-Reid

  DOI：10.1021/ja00047a080

  日期：1992.10
• n-Pentenyl Mannoside Precursors for Synthesis of the Nonamannan Component of High Mannose Glycoproteins
  作者：J. Robert Merritt、Elizabeth Naisang、Bert Fraser-Reid

  DOI：10.1021/jo00095a020

  日期：1994.8

  The high-mannose oligosaccharide 1 is present on the conserved V3 loop of the viral coat of HIV1 known as GP-120. The mannan portion of this molecule has been prepared by utilization of halogen-promoted n-pentenyl glycoside (NPG) coupling. Two advantageous properties of NPG's facilitated construction of 1, one being the ability to activate the donor, even when C2 esterified (i.e., ''disarmed''), with NIS/Et(3)SiOTf, under which all reactions are complete within the time required to take a TLC sample. The second advantage was the ''side-tracking'' strategy which allowed the pentenyl group of a glycosyl acceptor to be rendered temporarily inactive by conversion to the dibromide. After coupling, the ''side-tracked'' NPG could be reactivated by reductive elimination to serve as the glycosyl donor in a subsequent step. With the appropriately protected monosaccharide precursors in hand, the nonamannan could be assembled by a virtually iterative protocol involving deprotection-coupling- deprotection-coupling...etc. as the only synthetic manipulations.
• Methods for Debrominating 4,5-Dibromopentanyl Glycosides
  作者：J. Robert Merritt、John S. Debenham、Bert Fraser-Reid

  DOI：10.1080/07328309608005425

  日期：1996.1

  Debromination of 4,5-dibromopentanyl glycosides to (re)generate n-pentenyl glycosides has been accomplished using zinc, samarium(II) iodide, and sodium iodide, respectively. The choice of reagent is dependent upon the reactivity of the substrate, as well as the protecting groups thereon.