| 摘要 |
<p>PURPOSE:To prepare the titled compound useful as an intermediate for the preparation of antibiotics, in high yield, by condensing OH-protected aldonic acid lactone with trimethylsilylated diol compound in a solvent using trimethylsilyl triflate as a catalyst. CONSTITUTION:The glycosylidene acetal compound of formula IV (R may together form a ring) is prepared by condensing OH-protected aldonic acid lactone of formulaIwith trimethylsilylated diol compound of formula II (TMS is trimethylsilyl) in a solution using trimethylsilyl triflate as a catalyst. The reaction proceeds in an inert solvent such as dichloromethane at room temperature, and gives the objective compound in high yield. Moreover, an acetal in which two hydroxyl groups of a monosaccharide have participation, can be prepared also in high yield.</p> |
