26-O-β-D-glucopyranosyl-(25R)-22-hydroxyl-5-ene-furostane-3β,17α,26-triol 3-O-α-L-arabinofuranosyl-(1->4)-β-D-glucopyranoside | 945865-42-9

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 类固醇和类固醇衍生物
• 英文名称: 26-O-β-D-glucopyranosyl-(25R)-22-hydroxyl-5-ene-furostane-3β,17α,26-triol 3-O-α-L-arabinofuranosyl-(1->4)-β-D-glucopyranoside
• CAS: 945865-42-9
• 化学式: C₄₄H₇₂O₁₉
• 分子量: 905.044
• InChiKey: HOUKVBHYXFXTOR-DEAGMENTSA-N

反应信息

• 作为产物：
  描述：

  26-O-β-glucopyranosyl-(25R)-22-hydroxy-5-ene-furostane-3β,17α,26-triol 3-O-α-L-arabinofuranosyl-(1->4)-[α-L-rhamnopyranosyl-(1->2)]-β-D-glucopyranoside 在 Curvularia lunata 3.4381 1,4-α-D-glucan glucohydrolase 作用下， 以 phosphate buffer 为溶剂， 反应 6.0h， 以11.9 mg的产率得到(3β,17α,25R)-spirost-5-ene-3,17-diol-3-O-α-L-arabinofuranosyl-(1->4)-β-D-glucopyranoside
  参考文献：
  名称：

  The substrate specificity of a glucoamylase with steroidal saponin-rhamnosidase activity from Curvularia lunata

  摘要：

  In previous work, we studied and reported that an enzyme from Curvularia lunata 3.4381 had the novel specificity to hydrolyze the terminal rhamnosyl at C-3 position of steroidal saponin and obtained four transformed products; the enzyme was purified and ascertained as glucoamylase (EC 3.2.1.3 GA). In this work, the enzyme exhibiting steroidal saponin-rhamnosidase activity was systematically studied on 21 steroidal saponins and 6 ginsenosides. The results showed that the alpha-1,2-linked end-rhamnosyl residues at C-3 position of steroidal saponins could be hydrolyzed to corresponding secondary steroidal saponins, among which 18 compounds were isolated and identified, including 3 new secondary compounds. For the furostanosides having glucosyl residues at the C-26 position, hydrolysis occurred first at end- rhamnosyl at C-3 position to produce secondary furostanosides. The reaction of hydrolyzing glucosyl at C-26 position depended considerably on longer reaction times yielding the corresponding secondary spirostanosides ( without rhamnosyl and glucosyl residues). The enzyme had the strict specificity for the terminal alpha-1,2-linked rhamnosyl residues of linear chain, or the terminal alpha-1,2-linked rhamnosyl residues with branched chain of 1,4-linked glycosyl residues of sugar chain at C-3 position of steroidal saponins, it was not specific for different aglycones, different glycons, and the number of glycon of sugar chain of steroidal saponin. The end- rhamnosyl of ginsenosides and p-nitrophenyl-a-L-rhamnopyranoside (pNPR) could not be hydrolyzed by the enzyme from C. lunata. (c) 2007 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2007.04.076