methyl O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)-(1->4)-2,3-di-O-acetyl-β-D-xylopyranoside | 88299-99-4

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)-(1->4)-2,3-di-O-acetyl-β-D-xylopyranoside
• 英文别名: 2,3,2',3',4',6'-hexa-O-acetyl-6-deoxy-β-lactoside；Gal2Ac3Ac4Ac6Ac(b1-4)b-Xyl1Me2Ac3Ac；[(2R,3S,4S,5R,6S)-3,4,5-triacetyloxy-6-[(3R,4S,5R,6R)-4,5-diacetyloxy-6-methoxyoxan-3-yl]oxyoxan-2-yl]methyl acetate
• CAS: 88299-99-4
• 化学式: C₂₄H₃₄O₁₆
• 分子量: 578.524
• InChiKey: GYWMPRKNEQSIOQ-VENQHLRYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -0.7
• 重原子数：
  40
• 可旋转键数：
  16
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.75
• 拓扑面积：
  195
• 氢给体数：
  0
• 氢受体数：
  16

反应信息

• 作为反应物：
  描述：

  methyl O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)-(1->4)-2,3-di-O-acetyl-β-D-xylopyranoside 在 sodium methylate 作用下， 以 甲醇 为溶剂， 反应 2.0h， 以95%的产率得到methyl β-D-galactopyranosyl-(1->4)-β-D-xylopyranoside
  参考文献：
  名称：

  蓖麻凝集素对合成甲基β-乳糖苷类似物的分子识别研究。

  摘要：

  已经合成了甲基β-乳糖苷的2-，3-，6-，2'-，3'-，4'-和6'-脱氧衍生物和3-O-甲基衍生物，并且它们与半乳糖结合研究了来自蓖麻的特异性凝集素（RCA-120）。结果表明，β-D-吡喃半乳糖部分的HO-3、4、6是关键的极性基团。与紧密相关的蓖麻毒素凝集素RCA-60的主要区别在于D-吡喃葡萄糖部分的HO-6，这似乎有助于碳水化合物与RCA-60的结合而不与RCA-120的结合。

  DOI：

  10.1016/0008-6215(92)80055-6
• 作为产物：
  描述：

  乙酸酐 、 methyl β-D-galactopyranosyl-(1->4)-β-D-xylopyranoside 在 吡啶 作用下， 生成 methyl O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)-(1->4)-2,3-di-O-acetyl-β-D-xylopyranoside
  参考文献：
  名称：

  Enzymatic syntheses and selective hydrolysis of O-β-d-galactopyranosides using a marine mollusc β-galactosidase

  摘要：

  The use of crude extract of the hepatopancreas of Aplysia fasciata, a large mollusc belonging to the order Anaspidea containing a beta-galactosidase activity, was reported for the synthesis of different galactosides. Good yields with polar acceptors and the uncommon beta-1-3 selectivity in the transgalactosylation reactions with most of the acceptors were observed. A beta-1-2 selectivity in the hydrolytic conditions was also observed and discussed. (C) 2004 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.bmcl.2004.10.016

文献信息

• The effect of high pressure on the stereospecificity of the glycosylation reaction
  作者：Nikolay K. Kochetkov、Victor M. Zhulin、Evgeny M. Klimov、Nelly N. Malysheva、Zinaida G. Makarova、Andrej Ya. Ott

  DOI：10.1016/0008-6215(87)80133-7

  日期：1987.7

  a pressure of 1.4 GPa and room temperature, the glycosylation of trityl ethers by 1,2-O-cyanoethylidene derivatives of sugars, and the polycondensation of the proper monomers in dichloromethane, proceed with absolute stereospecificity, giving rise to a 1,2-trans-glycosidic linkage, although, at the ambient pressure, the reactions studied reveal a rather low stereospecificity. The effect of high pressure

  在1.4 GPa的压力和室温下，糖的1,2-O-氰基亚乙基衍生物对三苯甲基醚的糖基化作用以及适当单体在二氯甲烷中的缩聚反应具有绝对立体定向性，从而产生1,2-反式糖苷键，尽管在环境压力下，所研究的反应显示出较低的立体特异性。高压对糖苷键形成的立体特异性的影响被解释为是由于随着压力的增加，单环糖基阳离子和双环酰基氧鎓阳离子之间的平衡向后者转移。
• Reactivity of 1,2-O-cyanoalkylidene sugar derivatives in trityl-cyanoalkylidene condensation
  作者：P. I. Kitov、Yu. E. Tsvetkov、L. V. Backinowsky、N. K. Kochetkov

  DOI：10.1007/bf00699947

  日期：1993.8

  The rate-determining step of trityl-cyanoalkylidene condensation is the interaction between the cyanoalkylidene derivative (CD) and the triphenylmethyl cation. The rate of the reaction follows first-order kinetics with respect to both CD and the catalyst (Tr+) and is independent of the nature and concentration of the trityl ether. Glycosylation rate constants have been determined for CD's of most common monosaccharides.
• Linear dependence of the glycosylation stereoselectivity ofO-trityl ethers by carbohydrate 1,2-O-cyanoalkylidene derivatives on anion concentrations. Effect of substituents in the glycosyl acceptor and a new mechanism of 1,2-cis-glycosides formation
  作者：P. I. Kitov、Yu. E. Tsvetkov、L. V. Backinowsky、N. K. Kochetkov

  DOI：10.1007/bf00707066

  日期：1995.6

  The dependence of the stereochemical outcome of trityl-cyanoalkylidene condensation (alpha/beta-ratio of disaccharides) on the concentration of a catalyst (TrClO(4)) was studied. The dependence was shown to be linear over a wide range of concentrations of the catalyst. The mechanism of the reaction and the effect of the nature of protective groups in the glycosyl acceptor on the stereochemistry of glycosylation are discussed. A new mechanism of 1,2-cis-glycosides formation is proposed.