4,5-Di-O-benzyl-2-O-methyl-3-deoxy-D-erythro-2-hexulopyranosonic Acid | 135853-15-5

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: 4,5-Di-O-benzyl-2-O-methyl-3-deoxy-D-erythro-2-hexulopyranosonic Acid
• CAS: 135853-15-5；135853-17-7
• 化学式: C₂₁H₂₄O₆
• 分子量: 372.418
• InChiKey: IGLWDSCLRZNZQJ-QSJYAPKHSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.0
• 重原子数：
  27.0
• 可旋转键数：
  8.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.38
• 拓扑面积：
  74.22
• 氢给体数：
  1.0
• 氢受体数：
  5.0

反应信息

• 作为产物：
  描述：

  (3S,4R)-4,5-O-Isopropylidene-3,4,5-trihydroxy-1-(2-thiazolyl)-1-pentanone 在 sodium tetrahydroborate 、 水 、 四丁基碘化铵 、 sodium hydride 、 对甲苯磺酸 、 mercury dichloride 、 silver(l) oxide 作用下， 以 四氢呋喃 、 甲醇 、 乙腈 为溶剂， 反应 180.08h， 生成 4,5-Di-O-benzyl-2-O-methyl-3-deoxy-D-erythro-2-hexulopyranosonic Acid
  参考文献：
  名称：

  Chemistry of the enolates of 2-acetylthiazole: aldol reactions with chiral aldehydes to give 3-deoxy aldos-2-uloses and 3-deoxy 2-ulosonic acids. A short total synthesis of 3-deoxy-D-manno-2-octulosonic acid (KDO)

  摘要：

  The acetyl group of 2-acetylthiazole (2-ATT) was selectively metalated by treatment with lithium tert-butoxide (the lithium enolate was formed) or triethylamine/zinc chloride/trimethylsilyl chloride (the silyl enol ether was formed). The use of strong bases (LDA, TMP) resulted in substantial deprotonation of the thiazole ring. The lithium enolate of 2-ATT, formed under conditions of kinetic control, reacted with aliphatic and aromatic aldehydes to give the corresponding aldols (beta-hydroxyalkyl 2-thiazolyl ketones) in isolated yields of 51-65%. The reaction of the lithium enolate with chiral compounds, i.e., various alkoxy-substituted aldehydes and one amino aldehyde derivative, occurred with a high degree of anti diastereoselectivity (80-92%), an outcome that was in accord with the Felkin-Ahn model for asymmetric induction. Hemiketalization of the aldols that resulted from the reaction of the enolate with D-glyceraldehyde acetonide and 2-O-benzyl D-erythrose acetonide and subsequent liberation of the formyl group by hydrolytic cleavage of the thiazole ring afforded the corresponding aldosuloses. Oxidation converted these to ulosonic acids. The application of this three-carbon-chain elongation to D-arabinose diacetonide afforded the octulosonic acid KDO in 6.8% overall yield.

  DOI：

  10.1021/jo00018a017