phenyl ((3-(18)O)-β-D-(3-(18)O)galactopyranosyl)-(1->4)-1-thio-β-D-glucopyranoside | 1363661-34-0

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: phenyl ((3-(18)O)-β-D-(3-(18)O)galactopyranosyl)-(1->4)-1-thio-β-D-glucopyranoside
• CAS: 1363661-34-0
• 化学式: C₁₈H₂₆O₁₀S
• 分子量: 436.465
• InChiKey: FGJLUHTXBRGPSV-VMNQXVCPSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -2.6
• 重原子数：
  29.0
• 可旋转键数：
  6.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  169.3
• 氢给体数：
  7.0
• 氢受体数：
  11.0

反应信息

• 作为产物：
  描述：

  phenyl (2,3,6-tri-O-acetyl-β-D-(3-(18)O)galactopyranosyl)-(1->4)-2,3,6-tri-O-acetyl-1-thio-β-D-glucopyranoside 在 sodium methylate 作用下， 以 甲醇 为溶剂， 反应 5.25h， 以91%的产率得到phenyl ((3-(18)O)-β-D-(3-(18)O)galactopyranosyl)-(1->4)-1-thio-β-D-glucopyranoside
  参考文献：
  名称：

  Transition State Analysis of Vibrio cholerae Sialidase-Catalyzed Hydrolyses of Natural Substrate Analogues

  摘要：

  A series of isotopically labeled natural substrate analogues (phenyl 5-N-acetyl-alpha-u-neuraminyl-(2 -> 3)-alpha-D-galactopyranosyl-(2 -> 4)-1-thio-beta-D-glucopyranoside; Neu5Ac alpha 2,3Lac beta SPh, and the corresponding 2 -> 6 isomer) were prepared chemoenzymatically in order to characterize, by use of multiple kinetic isotope effect (KIE) measurements, the glycosylation transition states for Vibrio cholerae sialidase-catalyzed hydrolysis reactions. The derived KIEs for Neu5Ac alpha 2,3Lac beta SPh for the ring oxygen (V-18/K), leaving group oxygen (V-18/K), C3-S deuterium (V-D/K-S) and C3-R deuterium (V-D/K-R) are 1.029 +/- 0.002, 0.983 +/- 0.001, 1.034 +/- 0.002, and 1.043 +/- 0.002, respectively. In addition, the KIEs for Neu5Ac alpha 2,6 beta SPh for C3-S deuterium (V-D/K-S) and C3-R deuterium (V-D/K-R) are 1.021 +/- 0.001 and 1.049 +/- 0.001, respectively. The glycosylation transition state structures for both Neu5Ac alpha 2,3Lac beta SPh and Neu5Ac alpha 2,6Lac beta SPh were modeled computationally using the experimental KIE values as goodness of fit criteria. Both transition states are late with largely cleaved glycosidic bonds coupled to pyranosyl ring flattening (H-4(5) half-chair conformation) with little or no nucleophilic involvement of the enzymatic tyrosine residue. Notably, the transition state for the catalyzed hydrolysis of Neu5Ac alpha 2,6 beta SPh appears to incorporate a lesser degree of general-acid catalysis, relative to the 2,3-isomer.

  DOI：

  10.1021/ja208564y