methyl p-tolyl 5-acetamido 7,8,9-tri-O-acetyl-5-N,4-O-carbonyl-3,5-dideoxy-2-thio-D-glycero-β-D-galacto-2-nonulopyranosonate | 1246533-58-3

• 分子结构分类: 有机化合物
• 英文名称: methyl p-tolyl 5-acetamido 7,8,9-tri-O-acetyl-5-N,4-O-carbonyl-3,5-dideoxy-2-thio-D-glycero-β-D-galacto-2-nonulopyranosonate
• 英文别名: methyl (3aR,4R,6R,7aS)-3-acetyl-6-(4-methylphenyl)sulfanyl-2-oxo-4-[(1S,2R)-1,2,3-triacetyloxypropyl]-3a,4,7,7a-tetrahydropyrano[3,4-d][1,3]oxazole-6-carboxylate
• CAS: 1246533-58-3
• 化学式: C₂₆H₃₁NO₁₂S
• 分子量: 581.598
• InChiKey: YRDIRCKRRXTWGF-SFOUIMQPSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.1
• 重原子数：
  40
• 可旋转键数：
  13
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.54
• 拓扑面积：
  186
• 氢给体数：
  0
• 氢受体数：
  13

反应信息

• 作为反应物：
  描述：

  methyl p-tolyl 5-acetamido 7,8,9-tri-O-acetyl-5-N,4-O-carbonyl-3,5-dideoxy-2-thio-D-glycero-β-D-galacto-2-nonulopyranosonate 在 N-碘代丁二酰亚胺 、 三氟甲磺酸 作用下， 以 二氯甲烷-D2 为溶剂， 反应 0.08h， 生成 methyl 7,8,9-tri-O-acetyl-5-(N-acetyl)-5-N,4-O-carbonyl-2,3,5-trideoxy-D-glycero-Dgalacto-2-nonenopyranosonate
  参考文献：
  名称：

  Donor‐Reactivity‐Controlled Sialylation Reactions

  摘要：

  AbstractAlthough tremendous efforts have been made for the efficient preparation of sialosides, controlling the stereochemical outcome of sialylation reaction still remains one of the most challenging tasks due to the unique chemical structure of sialic acid. We developed a new strategy to statistically analyze the stereoselectivity of sialylation reactions on six types of p‐tolyl thiosialosides in NIS/TfOH system using Relative Reactivity Value (RRV) as the indicator. Analysis of the reaction mechanism showed the formation of the relatively stable glycosyl bromide and glycosyl chloride intermediates from halide‐ and triflate‐containing promotors in the absence of an acceptor. We found that the α/β‐stereoselectivity, yields, and intermediate changes were associated with their donor reactivity. These findings enable to tailor the most suitable building blocks for stereo‐controlled sialylation reactions.

  DOI：

  10.1002/ejoc.202100718
• 作为产物：
  描述：

  在 吡啶 、 乙酸酐 、 N,N-二异丙基乙胺 作用下， 以 二氯甲烷 为溶剂， 生成 methyl p-tolyl 5-acetamido 7,8,9-tri-O-acetyl-5-N,4-O-carbonyl-3,5-dideoxy-2-thio-D-glycero-β-D-galacto-2-nonulopyranosonate
  参考文献：
  名称：

  Comparative studies on the O-sialylation with four different α/β-oriented (N-acetyl)-5-N,4-O-carbonyl-protected p-toluenethiosialosides as donors

  摘要：

  Four types of 5-N,4-O-carbonyl-protected p-toluenethiosialosides were synthesized and their couplings with different acceptors were thoroughly investigated. The results indicate that the sialyl donor structure, the amount of glycosyl acceptor, and the detailed promotion conditions have great influence on the sialylation stereoselectivties and product yields. Under the (p-Tol)(2)SO/Tf2O activation conditions, the glycosylations with simple alcohols provided declined alpha-selectivities and higher yields with increasing the amounts of acceptors from 1.1 equiv to 2.0 equiv. However, the outcome of same sialylation was independent of the relative amounts of sugar alcohol acceptors. With NIS/TfOH as promoter, the alpha-selectivities of the sialylations were significantly improved compared with the cases activated by (p-Tol)(2)SO/Tf2O. In general, the difference in configuration of N-acetylated sialyl donors (D2 and D4) has little effect on the sialylation yield and stereoselectivity. In contrast, the N-deacetylated alpha/beta sialyl donors (D1 and D3) show complex sialylation profiles with different acceptors. (C) 2014 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.carres.2014.02.006

文献信息

• Highly efficient α-C-sialylation promoted by (p-Tol)2SO/Tf2O with N-acetyl-5-N,4-O-oxazolidione protected thiosialoside as donor
  作者：Zhen-yuan Gu、Xiao-tai Zhang、Jia-xin Zhang、Guo-wen Xing

  DOI：10.1039/c3ob40876k

  日期：——

  Based on a preactivation protocol with (p-Tol)2SO/Tf2O, a practical, straightforward, and high-yielding synthesis of α-sialyl C-glycosides was accomplished by coupling N-acetyl-5-N,4-O-oxazolidione protected thiosialoside with various trimethylsilyl enol ethers and allyltrimethylsilanes. High yields and excellent α-selectivities were obtained for the strong π-nucleophiles with large nucleophilicity values (N = 4.4–9.0), irrespective of whether silyl enol ethers, silyl ketene acetals or allyltrimethylsilanes were used for the electrophilic C-sialylation.

  基于(p-Tol)2SO/Tf2O预活化策略，通过N-乙酰基-5-N,4-O-恶唑烷酮保护的硫代唾液酸与各种三甲基硅基烯醇醚及烯丙基三甲基硅烷的偶联反应，实现了α-唾液酸型C-糖苷的实用、简便及高产率合成。对于具有大亲核性值（N = 4.4–9.0）的强π-亲核试剂，无论是硅醚烯醇、硅醚乙缩醛还是烯丙基三甲基硅烷作为亲电C-唾液酸化试剂，均能获得高产率和极佳的α-选择性。
• Pre-activation based, highly alpha-selective O-sialylation with N-acetyl-5-N,4-O-carbonyl-protected p-tolyl thiosialoside donor
  作者：Bin Sun、Heyan Jiang

  DOI：10.1016/j.tetlet.2011.09.022

  日期：2011.11

  A new method for pre-activation of N-acetyl-5-N,4-O-carbonyl-protected p-tolyl thiosialoside donor with AgOTf and p-toluenesulfenyl chloride followed by coupling with other p-tolyl thioglycosides is reported. Excellent alpha-sialylation yields were achieved for these coupling reactions, as high as 91% yield of only alpha-isomer. (C) 2011 Elsevier Ltd. All rights reserved.