Synthesis, characterization and X-ray structure of glycosyl-1,2-isoxazoles and glycosyl-1,2-isoxazolines prepared via 1,3-dipolar cycloaddition

Abstract A convenient preparative method of a series of glycosyl-1,2-isoxazoles ( 6–11 ) and glycosyl-1,2-isoxazolines ( 15–20 ) by a simple and efficient 1,3-dipolar cycloaddition of a series of aryl nitrile oxide, generated in situ from aryl oximes ( 4–5 ), with a variety of O -propargyl glycosyles ( 1 – 3 ) or O -allyl glycosyles ( 12–14 ) respectively, is reported. The carbohydrate-containing 1,2-isoxazoles and 1,2-isoxazolines compounds were isolated in excellent yields (81–91%) and they were fully characterized by 1 H, 13 C NMR and mass spectrometry. The relative stereochemistry of the glycosyl-1,2-isoxazole 10 was confirmed by single crystal X-ray analysis. The molecular structure of…