3-deoxy-L-manno-oct-2-ulosonic acid

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 3-deoxy-L-manno-oct-2-ulosonic acid
• 英文别名: 3-deoxy-L-manno-octulosonic acid；(2S,4S,5S,6S)-6-[(1S)-1,2-dihydroxyethyl]-2,4,5-trihydroxyoxane-2-carboxylic acid
• 化学式: C₈H₁₄O₈
• 分子量: 238.194
• InChiKey: NNLZBVFSCVTSLA-PEOQWYCYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -2.8
• 重原子数：
  16
• 可旋转键数：
  3
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.88
• 拓扑面积：
  148
• 氢给体数：
  6
• 氢受体数：
  8

反应信息

• 作为产物：
  描述：

  L-阿拉伯糖 、 sodium pyruvate 在 potassium phosphate buffer 、 1,4-二巯基-2,3-丁二醇 作用下， 以 水 为溶剂， 反应 72.0h， 生成 3-deoxy-L-manno-oct-2-ulosonic acid
  参考文献：
  名称：

  Unusual stereoselectivity in sialic acid aldolase-catalyzed aldol condensations: synthesis of both enantiomers of high-carbon monosaccharides

  摘要：

  An inversion of stereoselectivity in aldol condensations catalyzed by sialic acid aldolase (from Escherichia coli, Shinko American Inc.) was observed when L-mannose, 6-deoxy-L-mannose, L-talose, 2-deoxy-L-glucose, 2-deoxy-L-rhamnose, N-acetyl-L-mannosamine, D-gulose, D-arabinose, and 2-azido-2-deoxy-L-mannose were used as acceptor substrates. In all substrates tested, except the last three, a complete inversion of stereoselectivity was observed; i.e., the C-nucleophile of pyruvate attacks the re face of the acceptor carbonyl instead of the si face as in the normal case for the enantiomeric substrates. Examination of the product distribution during the course of enzymatic reactions indicates that the stereoselectivity is thermodynamically controlled in nature; i.e., attack on the re face would take place if the resulting product would be more stable than the one from the si face attack. Both enantiomers of several high-carbon monosaccharides are now accessible via the aldolase reactions. A new practical procedure has also been developed for the preparation of the aldolase products where unreacted pyruvate (usually used in 7-fold excess to drive the reaction) is decomposed with pyruvate decarboxylase to simplify product isolation.

  DOI：

  10.1021/ja00052a008

文献信息

• Unusual stereoselectivity in sialic acid aldolase-catalyzed aldol condensations: synthesis of both enantiomers of high-carbon monosaccharides
  作者：Chun Hung Lin、Takeshi Sugai、Randall L. Halcomb、Yoshitaka Ichikawa、Chi Huey Wong

  DOI：10.1021/ja00052a008

  日期：1992.12

  An inversion of stereoselectivity in aldol condensations catalyzed by sialic acid aldolase (from Escherichia coli, Shinko American Inc.) was observed when L-mannose, 6-deoxy-L-mannose, L-talose, 2-deoxy-L-glucose, 2-deoxy-L-rhamnose, N-acetyl-L-mannosamine, D-gulose, D-arabinose, and 2-azido-2-deoxy-L-mannose were used as acceptor substrates. In all substrates tested, except the last three, a complete inversion of stereoselectivity was observed; i.e., the C-nucleophile of pyruvate attacks the re face of the acceptor carbonyl instead of the si face as in the normal case for the enantiomeric substrates. Examination of the product distribution during the course of enzymatic reactions indicates that the stereoselectivity is thermodynamically controlled in nature; i.e., attack on the re face would take place if the resulting product would be more stable than the one from the si face attack. Both enantiomers of several high-carbon monosaccharides are now accessible via the aldolase reactions. A new practical procedure has also been developed for the preparation of the aldolase products where unreacted pyruvate (usually used in 7-fold excess to drive the reaction) is decomposed with pyruvate decarboxylase to simplify product isolation.