Trifluoroacetic Acid Promoted Ring Contraction in 2,3-Di-O-silylated O-Galactopyranosides and Hemiacetals
作者:Polina I. Abronina、Leonid O. Kononov、Nelly N. Malysheva、Alexander I. Zinin、Maxim Y. Karpenko、Natalya G. Kolotyrkina
DOI:10.1055/a-1730-9458
日期:2022.3
A pyranose ring contraction of 2,3-di-O-silylated O-galactopyranosides with retention of aglycone promoted by anhydrous trifluoroacetic acid (TFA) in CH2Cl2 was demonstrated for the first time. In addition, TFA-promoted pyranose ring contraction of 2,3-bis-O-(triisopropylsilyl)-d-galactopyranose with formation of the corresponding anomeric triols in furanose form was successfully performed. A representative
首次证明了在 CH 2 Cl 2中由无水三氟乙酸 (TFA) 促进的 2,3-二-O-甲硅烷基化的O-吡喃半乳糖苷的吡喃糖环收缩和苷元的保留。此外,TFA 促进了 2,3-bis- O -(triisopropylsilyl)-的吡喃糖环收缩d-吡喃半乳糖与呋喃糖形式的相应异头三醇的形成已成功进行。有代表性的一系列β-d已经研究了含有 Me、Bn、烯丙基或 3-(三氟乙酰胺基)丙基苷元的吡喃半乳糖苷。在 TFA 促进的吡喃糖环收缩条件下,发现 TBDPS 保护基团比 TIPS 基团更稳定。易于获得 2,3-二-O -TBDPS-取代的烯丙基和苄基呋喃半乳糖苷以及 2,3-双-O- (三异丙基甲硅烷基)-β-d-呋喃半乳糖在选择性保护的单糖结构单元的合成中可能具有优势,可用于合成生物学上重要的寡糖。