pent-4-enyl 2-O-benzoyl-3,4-di-O-benzyl-6-O-tert-butyldiphenylsilyl-3,4-di-O-benzyl-α-D-mannopyranoside | 470475-30-0

• 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: pent-4-enyl 2-O-benzoyl-3,4-di-O-benzyl-6-O-tert-butyldiphenylsilyl-3,4-di-O-benzyl-α-D-mannopyranoside
• 英文别名: [(2S,3S,4S,5R,6R)-6-[[tert-butyl(diphenyl)silyl]oxymethyl]-2-pent-4-enoxy-4,5-bis(phenylmethoxy)oxan-3-yl] benzoate
• CAS: 470475-30-0
• 化学式: C₄₈H₅₄O₇Si
• 分子量: 771.038
• InChiKey: GZJORPPLOJHQNW-OVZPAAAXSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  8.67
• 重原子数：
  56
• 可旋转键数：
  20
• 环数：
  6.0
• sp3杂化的碳原子比例：
  0.31
• 拓扑面积：
  72.4
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  pent-4-enyl 2-O-benzoyl-3,4-di-O-benzyl-6-O-tert-butyldiphenylsilyl-3,4-di-O-benzyl-α-D-mannopyranoside 在 sodium methylate 作用下， 生成 tert-butyl-[[(2R,3R,4S,5S,6S)-6-pent-4-enoxy-3,4,5-tris(phenylmethoxy)oxan-2-yl]methoxy]-diphenylsilane
  参考文献：
  名称：

  Synthesis of a key Mycobacterium tuberculosis biosynthetic phosphoinositide intermediate

  摘要：

  Regioselective mannosylations of a myoinositol acceptor diol are readily achieved by Lewis acid mediated iodinolysis of n-pentenyl ortho-esters. The procedure affords a psuedotrisaccharide to which the phosphoglyceryl and other lipid residues are added leading to the key biosynthetic intermediate of Mycobacterium species. (C) 2004 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.bmcl.2004.04.103
• 作为产物：
  描述：

  3,4,6-tri-O-benzoyl-β-D-mannopyranose 1,2-(pent-4-enyl orthobenzoate) 在 4-二甲氨基吡啶 、 sodium methylate 、 三乙胺 、 ytterbium(III) triflate 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 反应 15.0h， 生成 pent-4-enyl 2-O-benzoyl-3,4-di-O-benzyl-6-O-tert-butyldiphenylsilyl-3,4-di-O-benzyl-α-D-mannopyranoside
  参考文献：
  名称：

  Jayaprakash; Fraser-Reid, Bert, Organic Letters, 2004, vol. 6, # 23, p. 4211 - 4214

  摘要：

  DOI：

文献信息

• Reciprocal donor acceptor selectivity (RDAS): A new concept for "matching" donors with acceptors
  作者：Bert Fraser-Reid、J Cristobal Lopez、K V Radhakrishnan、Mateusz Mach、Urs Schlueter、Ana Gomez、Clara Uriel

  DOI：10.1139/v02-137

  日期：2002.8.1

  Lemieux's extensive work on replacement reactions at the anomeric center helped to establish the fact that the O-2-protecting group of a donor exerts powerful control over stereoselectivity in glycoside coupling reactions. This manuscript shows that the O-2-protecting group of a donor also exerts powerful, indeed sometimes total, control over regioselectivity in glycosidation of diols. The latter acceptors also exhibit preferences over the donor, thereby providing evidence for the concept of reciprocal donor acceptor selectivity (RDAS). The latter concept is put to the test by simultaneously presenting an acceptor diol with equivalent amounts of two donors, in the hope of achieving double differential glycosidation leading to one-pot assembly of a trisaccharide. When the pair of donors did not conform to RDAS principles the reaction did not proceed beyond a dissacharide. However, when the pair was RDAS sanctioned, a single trisaccharide (out of four possibilities) was obtained.Key words: regiocontrolled glycosidation, armed and disarmed donors, di- and trioxolenium ions, oxocarbenium ion.

  Lemieux在异构中心的替代反应方面的广泛研究有助于确立这样一个事实：供体的O-2保护基在糖苷偶联反应中对立体选择性具有强大的控制作用。本文表明，供体的O-2保护基对二醇的糖苷化反应的位置选择性也具有强大的、有时甚至是完全的控制作用。后一种受体对供体也表现出偏好，从而为相互供体受体选择性（RDAS）概念提供了证据。后一概念通过同时将一个受体二醇与等量的两个供体呈现，希望实现双重差异糖苷化，从而实现三糖的一锅法组装。当这对供体不符合RDAS原则时，反应无法超过二糖。然而，当这对供体符合RDAS原则时，获得了一个单一的三糖（四种可能性中的一种）。关键词：位置控制的糖苷化，武装和非武装供体，二和三氧杂环丙阳离子，羰基离子。
• Evidence for Efficient Unpromoted Regioselective Reactions of Vicinal and Non-Vicinal Diols
  作者：B. Fraser-Reid、J. C. Lopez、G. nair Anilkumar、J. C. Lopez、L. G. Nair、A. Gomez、C. Uriel、K. V. Radhakrishnan

  DOI：10.1071/ch01146

  日期：——

  reports that the NPOE and (NPGAC) donors frequently react at only one of the two hydroxy groups in good yield, whereas the corresponding benzylated donor (NPGALK) is less discriminating, and frequently gives lower yields. In a key experiment to examine the basis of the selectivity, it was found that the highly hindered C3 OH of 4,6-O-benzylidene methyl a-D-altropyranoside was selectively glycosylated

  Angyal 实验室 1965 年发表的一篇文章报道说，四氧苄基肌醇的顺式邻位二醇基团与赤道 OH 处的酰化剂发生区域选择性反应，有时仅与酰化剂反应，但与轴向 OH 处的烷化剂反应。Fraser-Reid 及其同事最近的报告表明，对于四-O-苄基肌醇的反式-1,3-二醇以及二-O-烯丙基甘露吡喃糖苷的 C2-C4 羟基也发现了这种选择性. 此外，后者的工作人员报告说区域选择性可以扩展到糖苷化反应。因此，正戊烯基原酸酯 (NPOE) 和 2-O-酰基正戊烯基糖苷 (NPGAC) 供体在赤道 OH 处优先反应（如果不是排他性的），而 2-O-烷基对应物 (NPGALK) 则产生混合物，通常主要糖苷化发生在轴向 OH。本手稿检查了几种邻二醇，并报告说 NPOE 和 (NPGAC) 供体经常仅在两个羟基中的一个上反应，产率很高，而相应的苄基化供体 (NPGALK) 区分度较低，并且经常给出较低的产
• Regioselective Strategies Mediated by Lanthanide Triflates for Efficient Assembly of Oligomannans
  作者：K. N. Jayaprakash、Siddhartha Ray Chaudhuri、Changalvala V. S. R. Murty、Bert Fraser-Reid

  DOI：10.1021/jo070018t

  日期：2007.7.1

  trichloroacetimidates as well as ethyl and phenyl thioglycosides can be achieved. Appropriate NPOEs are also able to provide 2,6 and 3,6 diol acceptors via rearrangement or glycoside formation, and these can be used for one-pot, sequential glycosidations based on orthogonal donors, and in situ double differential glycosidations. Thus NPOEs activated by iodonium ion, specifically generated from ytterbium

  现成的甘露糖基正戊烯基原酸酯（NPOE）本身可作为供体，也可作为其他糖基供体（如n-戊烯基糖苷（NPG），硫代糖苷和三氯乙亚氨酸盐。这些不同的供体被不同的试剂激活，因此适合多种用途。flat和flat三氟甲磺酸盐对这些供体的反应非常不同，其结果是可以实现NPOE，NPG，三氯乙亚氨酸盐以及乙基和苯基硫代糖苷之间的化学选择性区分。适当的NPOE也能够通过重排或糖苷形成提供2,6和3,6二醇受体，并且它们可用于基于正交供体的一锅顺序糖苷化和原位双差分糖苷化。因此，由碘鎓离子激活的NPOE，特别是由三氟甲磺酸/ N-碘代琥珀酰亚胺可用于快速单糖苷化二醇，具有出色的区域选择性，有时还具有化学选择性。残留的NPOE被转化为对反应条件具有抵抗力的脱甲NPG，因此不会对单糖苷化产物的游离OH构成威胁。然后可以通过直接添加三氯乙酰亚胺酸酯或乙基硫代糖苷来实现后者的进一步糖苷化。该基本策略已被用于制备支链五
• Efficient Chemical Synthesis of a Dodecasaccharidyl Lipomannan Component of Mycobacterial Lipoarabinomannan
  作者：Bert Fraser-Reid、Siddhartha Ray Chaudhuri、K. N. Jayaprakash、Jun Lu、Changalvala V. S. Ramamurty

  DOI：10.1021/jo802000p

  日期：2008.12.19

  Lipomannan (LM) is one of the domains of lipoarabinomannan (LAM) glycolipids, the latter being one of several cell surface organic molecules that fortify mycobacterial species against external attack. Some members of mycobacterial families are pathogenic, most notably Mycobacterium tuberculosis and Mycobacterium leprae, while others are nonpathogenic, and used in the clinic, such as Mycobacterium smegmatis. Additional biological significance arises from the fact that LM has been implicated in several health disorders outside of those associated with mycobacterial pathogens, notably for treatment of bladder cancer. LM is comprised of a heavily lipidated phosphoinositide dimannoside headgroup, from which a mannan array, of varied complexity, extends. The latter consists of a 1,6-alpha-linked backbone flanked at position O2, not necessarily regularly, with alpha-linked mannosides. This paper gives an example of lipomannan synthesis in which all of the sugar components, whether functioning as donors or acceptors, are obtained from n-pentenyl orthoesters, themselves in turn prepared in three easy steps from D-mannose. Assembly of the mannan array is facilitated by the exquisite regioselectivity occasioned by the use of ytterbium triflate/N-iodosuccinimide as the trigger for reaction of n-pentenyl orthoesters.
• Jayaprakash; Fraser-Reid, Bert, Organic Letters, 2004, vol. 6, # 23, p. 4211 - 4214
  作者：Jayaprakash、Fraser-Reid, Bert

  DOI：——

  日期：——