Allyl 2-acetamido-4,6-O-benzylidene-2-deoxy-α-D-allopyranoside | 138456-61-8

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃二恶英
• 英文名称: Allyl 2-acetamido-4,6-O-benzylidene-2-deoxy-α-D-allopyranoside
• 英文别名: Allyl 2-acetamido-4,6-O-benzylidene-2-deoxy-β-D-allopyranoside
• CAS: 138456-61-8
• 化学式: C₁₈H₂₃NO₆
• 分子量: 349.384
• InChiKey: RZNDVHTWHYQMRO-OOOWVJFSSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.89
• 重原子数：
  25.0
• 可旋转键数：
  5.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  86.25
• 氢给体数：
  2.0
• 氢受体数：
  6.0

反应信息

• 作为反应物：
  描述：

  Allyl 2-acetamido-4,6-O-benzylidene-2-deoxy-α-D-allopyranoside 在 吡啶 、 sodium hydroxide 、 三乙胺 作用下， 以 甲醇 为溶剂， 反应 160.5h， 生成 Allyl 3-O-acetyl-4,6-O-benzylidene-2-deoxy-2-phthalimido-β-D-allopyranoside
  参考文献：
  名称：

  Synthesis ofN-Acetylallosamine-Derived Disaccharides

  摘要：

  AbstractThe protected disaccharide 44, a precursor for the synthesis of allosamidin, was prepared from the glycosyl acceptor 8 and the donors 26–28, best yields being obtained with the trichloroacetimidate 28 (Scheme 6). Glycosidation of 8 or of 32 by the triacetylated, less reactive donors 38–40 gave the disaccharides 46 and 45, respectively, in lower yields (Scheme 7). Regioselective glycosidation of the diol 35 by the donors 38–40 gave 42, the axial, intramolecularly H‐bonded OHC(3) group reacting exclusively (Scheme 5). The glycosyl acceptor 8 was prepared from 9 by reductive opening of the dioxolane ring (Scheme 3). The donors 26–28 were prepared from the same precursor 9 via the hemiacetal 25. To obtain 9, the known 10 was de‐N‐acetylated (→ 18), treated with phthalic anhydride (→ 19), and benzylated, leading to 9 and 23 (Schemes 2 and 3). Saponification of 23, followed by acetylation also gave 9. Depending upon the conditions, acetylation of 19 yielded a mixture of 20 and 21 or exclusively 20. Deacetylation of 20 led to the hydroxyphthalamide 22. De‐N‐acetylation of the 3‐O‐benzylated β‐D‐glycosides 11 and 15, which were both obtained from 10, was very sluggish and accompanied by partial reduction of the O‐allyl to an O‐propyl group (Scheme 2). The β‐D‐glycoside 30 behaved very similarly to 11 and 15. Reductive ring opening of 31, derived from 29, yielded the 3‐O‐acetylated acceptor 32, while the analogous reaction of the β‐D‐anomer 20 was accompanied by a rapid 3‐O→4‐O acyl migration (→34; Scheme 4). Reductive ring opening of 21 gave the diol 35. The triacetylated donors 38–40 were obtained from 20 by debenzylidenation, acetylation (→36), and deallylation (→37), followed by either acetylation (→38), treatment with Me3SiSEt (→39), or Cl3CCN (→ 40).

  DOI：

  10.1002/hlca.19920750505
• 作为产物：
  描述：

  D-GlcNAc 在 乙二醇甲醚 、 三氟化硼乙醚 、 sodium acetate 、 三乙胺 、 zinc(II) chloride 作用下， 以 水 为溶剂， 反应 94.33h， 生成 Allyl 2-acetamido-4,6-O-benzylidene-2-deoxy-α-D-allopyranoside
  参考文献：
  名称：

  亚糖基卡宾。第4部分。由乙酰胺基糖基亚砜衍生的二嗪合成螺环丙烷

  摘要：

  描述了由N-乙酰基葡糖胺6合成第一糖基亚烷基衍生的2-乙酰氨基-2-脱氧重氮嗪4。因此，通过用烯丙醇糖基化，亚苄基化和甲磺酰化，将6转化为3- O-甲磺酰基吡喃葡萄糖苷9（方案2）。9的溶剂分解产生了异氰基吡喃糖苷10，经苄基化和糖苷裂解后，生成了半缩醛12。使用我们建立的方法（通过内酯肟14和重氮丙啶16），12给了重氮4。在i-PrOH存在下将该二嗪嗪热解，得到二氢-1,3-恶唑5（反应路线1）；在丙烯腈存在下，获得了四个非对映异构体螺环丙烷17-20和对乙酰氨基苯甲醛21并通过制备进行了分离。HPLC（方案3）。17–20构型的分配基于NOE的测量结果以及CN基团的反磁各向异性的影响。与早先的结果一致的四个环丙烷的比例是合理的。

  DOI：

  10.1002/hlca.19910740625

文献信息

• Why Is Direct Glycosylation with <i>N</i>-Acetylglucosamine Donors Such a Poor Reaction and What Can Be Done about It?
  作者：Mikkel H. S. Marqvorsen、Martin J. Pedersen、Michelle R. Rasmussen、Steffan K. Kristensen、Rasmus Dahl-Lassen、Henrik H. Jensen

  DOI：10.1021/acs.joc.6b02305

  日期：2017.1.6

  chemical glycosylation is challenging since direct reactions are low yielding. This issue, generally agreed upon to be caused by an intermediate 1,2-oxazoline, is often bypassed by introducing extra synthetic steps to avoid the presence of the NHAc functional group during glycosylation. The present paper describes new fundamental mechanistic insights into the inherent challenges of performing direct glycosylation

  单糖N-乙酰基-d-葡糖胺（GlcNAc）是天然存在的低聚糖中丰富的组成部分，但是由于直接反应的收率低，因此通过化学糖基化的方法引入葡糖胺极具挑战性。通常认为是由中间体1,2-恶唑啉引起的此问题通常通过引入额外的合成步骤来避免，以避免在糖基化过程中出现NHAc官能团。本文介绍了对使用GlcNAc执行直接糖基化的内在挑战的新的基本机械学见解。这些结果表明，控制恶唑啉形成和糖基化的平衡是获得可接受的化学收率的关键。通过运用这种推理方法直接与GlcNAc的传统硫糖苷供体直接进行糖基化，否则其糖基化收率不佳，