2,3-di-O-acetyl-4,6-O-ethylylideneglucosyl bromide | 116490-77-8

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 2,3-di-O-acetyl-4,6-O-ethylylideneglucosyl bromide
• 英文别名: 2,3-di-O-acetyl-4,6-O-ethylidene-α-D-glucopyranosyl bromide；[(4aR,6R,7R,8S,8aR)-7-acetyloxy-6-bromo-2-methyl-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxin-8-yl] acetate
• CAS: 116490-77-8
• 化学式: C₁₂H₁₇BrO₇
• 分子量: 353.167
• InChiKey: YIWIETMVYYDMNO-INAIMYKGSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.8
• 重原子数：
  20
• 可旋转键数：
  4
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.83
• 拓扑面积：
  80.3
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  2,3-di-O-acetyl-4,6-O-ethylylideneglucosyl bromide 生成 3-O-acetyl-1,2-cyanoethylidene-4,6-O-ethylidene-α-D-glucopyranose
  参考文献：
  名称：

  GRZESZCZYK, B.;BANASZEK, A.;ZAMOJSKI, A., CARBOHYDR. RES., 175,(1988) N 2, 215-226

  摘要：

  DOI：
• 作为产物：
  描述：

  1,2,3-tri-O-acetyl-4,6-O-ethylidene-α-D-glucopyranose 在 氢溴酸 作用下， 以 二氯甲烷 为溶剂， 反应 2.0h， 生成 2,3-di-O-acetyl-4,6-O-ethylylideneglucosyl bromide
  参考文献：
  名称：

  流感嗜血杆菌两个荚膜抗原重复单元的合成

  摘要：

  流感嗜血杆菌型荚膜抗原的重复单元2-O-β-D-吡喃葡萄糖基-L-核糖醇4'-和1-磷酸酯是通过α-D-吡喃葡萄糖基溴化物衍生物与5-O-烯丙基缩合而合成的-1,2,3-三-O-苄基-D-核糖醇，然后对HO-4'或HO-1进行选择性脱保护，磷酸化并去除保护基。

  DOI：

  10.1016/0008-6215(88)84144-2

文献信息

• Variously substituted glycals are readily prepared from glycosyl bromides using (Cp2TiCl)2
  作者：Roxanne P Spencer、Jeffrey Schwartz

  DOI：10.1016/0040-4039(96)00865-9

  日期：1996.6

  Glycosyl halides, variously substituted with ether, acetal, or ester protecting groups, were converted to the corresponding glycals in high yield by reaction with (Cp2TiCl)2. A glycosyl chloride was less reactive than the analogous bromide.

  通过与（C p2 TiCl）2反应，高产率地将被醚，缩醛或酯保护基不同取代的糖基卤化物转化为相应的糖基。糖基氯的反应性低于类似的溴化物。
• Rapid Preparation of Variously Protected Glycals Using Titanium(III)
  作者：Roxanne P. Spencer、Cullen L. Cavallaro、Jeffrey Schwartz

  DOI：10.1021/jo982447k

  日期：1999.5.1

  Glycosyl chlorides and bromides can be rapidly converted to glycals in high yield by reaction with (Cp2Ti[III]Cl)(2). This reagent tolerates a wide range of common carbohydrate protecting groups, including silyl ethers, acetals, and esters; the methodology provides a general route for the preparation of glycals substituted with both acid- and base-labile functionality. A reaction mechanism is proposed that is based on heteroatom abstraction to give an intermediate glycosyl radical. This radical reacts with a second equivalent of Ti(III) to yield a glycosyltitanium(IV) species. P-Heteroatom elimination from the glycosyltitanium(IV) complex gives the glycal.